| 1. |
- Abdullah, Mukhalad, et al.
(författare)
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Missing rainfall data estimation—an approach to investigate different methods: case study of Baghdad
- 2022
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Ingår i: Arabian Journal of Geosciences. - : Springer. - 1866-7511 .- 1866-7538. ; 15
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Tidskriftsartikel (refereegranskat)abstract
- The missing of the meteorological data in Iraq is common due to malfunction of measuring devices, security status, and human effects. The study tested 17 missing precipitation data estimation methods in Baghdad city as a case study, where, all the surrounding stations around Baghdad experienced the missing of data for various reasons, and some of the missing data are for a full year record. The methods examined in this study are based on different approaches, some of the methods are based upon the distances to the targeted station, others are upon regression factors, and there are also methods that combine several factors. There are also other types of missing data filling methods which depend on imputation and artificial intelligence. The investigation of the most accurate method to find the missing data will assist researchers and decision makers to fill the gap in their analysis in one of the most vulnerable countries in terms of drought and climate changes impacts. Results showed that Expectation Maximization (EM) method utilization has the best results with the least errors, and Multiple Linear Regression (MLR) method was ranked the second best method. In general, all of the applied methods had resulted acceptable interpolations, and it was clear that the combined methods have low significance on the results in comparison with others. All of these findings are limited to the study area meteorological and spatial conditions.
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| 2. |
- Abed Hussain, Tariq, et al.
(författare)
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Simulation of the ground water flow in Karbala Governorate, Iraq
- 2021
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Ingår i: Environmental Earth Sciences. - USA : Springer Nature. - 1866-6280 .- 1866-6299. ; 80, s. 1-6
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Tidskriftsartikel (refereegranskat)abstract
- The investigation region is found in the central part of Iraq within the of Karbala Governorate, where it is located in thewestern part of the Governorate and Lake Razaza in the north of the region, while in the western and southern part of theregion is Anbar Governorate and geographically (43° 10′ 25.7″, 43° 39″ 0.3″) longitude and (32° 10′ 25.7″, 32° 36′ 25.7″)latitude. The area of study is about 2400 Km2.The groundwater modeling system (GMS) v10.3 program was used for themodeling of ground water in the area containing about 22 wells distributed throughout the study area and the discharge ofthese wells ranges from 7 to 100 l/s and the rate of discharge of these wells up to 36 l/s. The model was initially operatedwithin a steady state and after obtaining a match between the models results with the initial values of groundwater levels,the results of this case were adopted as inputs to run the model within the unsteady state. The model was worked within thesight of the above wells for 3 years and the results of the operation indicate a decrease in groundwater levels ranging from2 to 21 m distributed uniformly throughout the study area.
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| 3. |
- Al-Khuzaie, Marwah M., et al.
(författare)
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Assessment model of water harvesting and storage location using GIS and remote sensing in Al-Qadisiyah, Iraq
- 2020
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Ingår i: Arabian Journal of Geosciences. - USA : Springer. - 1866-7511 .- 1866-7538. ; 13:21
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Tidskriftsartikel (refereegranskat)abstract
- One of the important steps towards optimizing land productivity and water availability for the semi-arid and arid areas is the identification of potential sites for water harvesting. Therefore, this paper uses the Geographical Information System (GIS) techniques to select the optimized sites for water harvesting in Al-Qadisiyah Governorate, Iraq. Geographic water management capabilities are applied as a spatial analysis model. Data from global data repositories are retrieved followed by rescaling them to a spatial resolution to acquire a manageable input data set. The Soil Conservation Service Curve Number (SCS-CN) model is used to calculate the potential runoff as an intermediate input. Multi-Criteria Evaluation techniques are adopted to identify the relative importance and suitability levels of the input parameters set to manage the water supply. The suitability for identifying irrigation pond and dam location(s) was considered in this study. To achieve this goal, the criteria for eligibility for water harvesting areas have been completed on the basis of the conditions in the study methods. Based on the hydrological and geomorphological standards of the study area, suitable sites for harvest areas were identified and it was divided into four classes in terms of their suitability for water harvesting, namely very low, low, moderate, and high suitable for water harvesting. It can be concluded that the findings of this research can be used to assist in water resources management as an efficient planning tool to ensure sustainable development of the water in Iraq who suffers from water shortages.
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| 4. |
- Al Maliki, Ali A., et al.
(författare)
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Assessment of the groundwater suitability for irrigation near Al Kufa City and preparing the final water quality maps using spatial distribution tools
- 2020
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Ingår i: Environmental Earth Sciences. - Germany : Springer. - 1866-6280 .- 1866-6299. ; 79:13, s. 1-12
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Tidskriftsartikel (refereegranskat)abstract
- In many parts of the world, groundwater quality is decreasing due to urbanization industrialization and use of agricultures in rural areas. This subject has formed an urgent need to determine the suitability of groundwater for various purposes. The aim of this study is to determine a groundwater index for groundwater use for irrigation in agriculture. The study is carried out in an agricultural area; near Al Kufa city, North of Al Najaf province, Iraq. Many chemical variables are used in this model, including (total dissolved solids TDS, electrical conductivity EC, sodium Na, potassium K and iron Fe), in addition to some of the heavy metals (cadmium Cd, lead Pb, chromium Cr, and nickel Ni), that also added to the index. The weight’s parameters are determined using analytical hierarchy process (AHP) and classified into five groups based on the human health significance of these parameters and negative effect on agriculture. The result of this study indicates that the water quality index (WQI) records values between (0 and 4.33), and in which the value of (2.16) represents the limit between unpolluted and polluted groundwater. This study confirms that all groundwater samples over the study area are suitable for agriculture. The final WQI values are exported to ArcMap environment to prepare the final WQI maps of study area.
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| 5. |
- Al-Maliki, Laheab A., et al.
(författare)
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Perception of climate change effects on water resources : Iraqi undergraduates as a case study
- 2022
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Ingår i: Arabian Journal of Geosciences. - : Springer. - 1866-7511 .- 1866-7538. ; 15:6
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Tidskriftsartikel (refereegranskat)abstract
- Developing countries suffer from the effects of climate change on water resources more than other countries. This paper aims to specify the undergraduates’ knowledge about climate change effects on water resources. This study was conducted through a questionnaire distributed using Google form in May 2021. Descriptive analysis was used to display the level of awareness, and then the correlation between the respondents’ gender, stage, and scientific specialization were analyzed. The results showed that the general knowledge for all questionaries ranged between 40 and 50 %. Moreover, a weak positive correlation with the highest Spearman’s rho of 0.15 was shown for the students’ gender with their understanding of climate change main cause by 0.06 for the academic stage versus knowledge of climate change causes. Moreover, the results indicated a weak role for university education in exchange for a prominent role for television and social media in raising awareness. The research recommends integrating the Environmental Education (EE) programs into the Iraqi educational systems as it proposes a systematic educational method through which climate change and other environmental problems may be addressed holistically at all educational levels.
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| 6. |
- Al‑Mamoori, Sohaib Kareem, et al.
(författare)
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Statistical analysis of the best GIS interpolation method for bearing capacity estimation in An-Najaf City, Iraq
- 2021
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Ingår i: Environmental Earth Sciences. - : Springer. - 1866-6280 .- 1866-6299. ; 80:20
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Tidskriftsartikel (refereegranskat)abstract
- The presence of an economical solution to predict soil behaviour is essential for new construction areas. This paper aims to investigate the ultimate interpolation method for predicting the soil bearing capacity of An-Najaf city-Iraq based on field investigation information. Firstly, the engineering bearing capacity was calculated based on the in-site N-SPT values using dynamic loading for 464 boreholes with depths of 0–2 m, using the Meyerhof formula. The data then were classified and imported to the GIS program to apply the interpolation methods. Four deterministic and two geostatistical interpolation methods were applied to produce six bearing capacity maps. The statistical analyses were performed using two methods: the common cross-validation method by the coefficient of determination (R2) and root mean square error (RMSE), where the results showed that ordinary kriging (OK) is the ultimate method with the least RMSE and highest R2. These results were confusing so, the backward elimination regression (BER) procedure was applied to gain the definite result. The results of BER show that among all the deterministic methods, the IDW is the optimal and most significant interpolation method. The result of geostatistical methods shows that EBK is the best method in our case than the OK method. BER also applied to all six methods and shows that IDW is the ultimate significant method. The results indicate no general ultimate interpolation method for all cases and datasets type; therefore, the statistical analyses must be performed for each case and dataset.
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| 7. |
- Chabuk, Ali, et al.
(författare)
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Water quality assessment along Tigris River (Iraq) using water quality index (WQI) and GIS software
- 2020
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Ingår i: Arabian Journal of Geosciences. - Switzerland : Springer. - 1866-7511 .- 1866-7538. ; 13:14
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Tidskriftsartikel (refereegranskat)abstract
- Most of the third world countries having rivers passing through them suffer from the water contaminant problem. This problem is considered so difficult to get the water quality within the standard allowable limits for drinking, as well as for industrial and agricultural purposes. This research aims to assess the water quality of the Tigris River using the water quality index method and GIS software. Twelve parameters (Ca, Mg, Na, K, Cl, SO4, HCO3, TH, TDS, BOD5, NO3, and EC) were taken from 14 stations along the river. The weighted arithmetic method was applied to compute the water quality index (WQI). The interpolation method (IDW) was applied in ArcGIS 10.5 to produce the prediction maps for 12 parameters at 11 stations along the Tigris River during the wet and dry seasons in 2016. The regression prediction was applied on three stations in the Tigris River between observed values and predicted values, from the prediction maps, in both seasons. The results showed that the regression prediction for all parameters was given the acceptable values of the determination coefficient (R2). Furthermore, the state of water quality for the Tigris River was degraded downstream of the Tigris River, especially at the station (8) in Aziziyah in the wet and dry seasons and increase degradation clearly at Qurnah (Basrah province) in the south of Iraq. This paper considers the whole length of the Tigris River for the study. This is important to give comprehensive knowledge about the contamination reality of the river. Such that it becomes easier to understand the problem of contamination, analyze it, and then find the suitable treatments and solutions.
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| 8. |
- Dochev, Dimitar Milkov, 1981, et al.
(författare)
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A Technology Demonstrator for 1.6–2.0 THz Waveguide HEB Receiver with a Novel Mixer Layout
- 2011
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Ingår i: Journal of Infrared, Millimeter, and Terahertz Waves. - : Springer Science and Business Media LLC. - 1866-6892 .- 1866-6906. ; 32:4, s. 451-465
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, we present our studies on a technology demonstrator for a balanced waveguide hot-electron bolometer (HEB) mixer operating in the 1.6–2.0 THz band. The design employs a novel layout for the HEB mixer combining several key technologies: all-metal THz waveguide micromachining, ultra-thin NbN film deposition and a micromachining of a silicon-on-insulator (SOI) substrate to manufacture the HEB mixer. In this paper, we present a novel mixer layout that greatly facilitates handling and mounting of the mixer chip via self-aligning as well as provides easy electrical interfacing. In our opinion, this opens up a real prospective for building multi-pixel waveguide THz receivers. Such receivers could be of interest for SOFIA, possible follow up of the Herschel HIFI, and even for ground based telescopes yet over limited periods of time with extremely dry weather (PWV less than 0.1 mm).
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| 9. |
- Elbeltagi, Ahmed, et al.
(författare)
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Optimizing hyperparameters of deep hybrid learning for rainfall prediction: a case study of a Mediterranean basin
- 2022
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Ingår i: Arabian Journal of Geosciences. - : Springer. - 1866-7511 .- 1866-7538. ; 15
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Tidskriftsartikel (refereegranskat)abstract
- Predicting rainfall amount is essential in water resources planning and for managing structures, especially those against floods and long-term drought establishment. Machine learning techniques can produce good results using a minimum dataset requirement, making it a leader among the prediction algorithms. This work develops a hybrid learning model for monthly rainfall prediction at four geographical locations representing Mediterranean basins in Northern Algeria and desert areas in Egypt. The study proposes an adaptive dynamic-based hyperparameter optimization algorithm to improve the accuracy of hybrid deep learning models. The proposed model provided a good fit, based on the obtained Nash-Sutcliffe efficiency index (NSE ≈ 0.90) with a high correlation coefficient of R ≈ 0.96, providing improvements of up to 62% in the RMSE. The proposed method proved to be an encouraging and promising tool to simulate water cycle components for better water resources management and protection.
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| 10. |
- Elias, Ziyad, et al.
(författare)
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Evaluation of the drainage system of Zagros Basin (Greater Zab River, northern Iraq) and insights into tectonic geomorphology
- 2020
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Ingår i: Arabian Journal of Geosciences. - : Springer. - 1866-7511 .- 1866-7538. ; 13:22
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Tidskriftsartikel (refereegranskat)abstract
- Geomorphological evaluation was carried out for three drainage basins named Hareer, Dwaine, and Hijran, which are tributaries of the Greater Zab River in the northern part of Erbil Governorate, the Iraqi Kurdistan Region, north Iraq. The exposed rocks in the three basins are mainly clastic rocks (sandstone, claystone, and conglomerate, with subordinate gypsum and limestone beds). However, in the uppermost parts of the basins, thick and massive carbonate rocks are exposed. Tectonically, the three basins are located in the Low Folded and High Folded Zones, which belong to the Zagros Fold–Thrust Belt. The main aim of the current study is to deduce the tectonic activity of the area occupied by the studied three basins. We have used and interpreted Radar Topography Mission (SRTM) data to perform the geomorphological evaluation. Different geomorphological indices and forms were used to deduce the tectonic activity of the area occupied by the three basins. Accordingly, seven orders of streams were identified in the three basins. The number of the streams with low order (i.e., 1) joining with higher order (i.e., 6 and 7) is considerably higher in the three basins. The Hat values of the three basins are 12,971, 10,479, and 7014 in Hareer, Dwaine, and Hijran basins, respectively. The values of hierarchical anomaly index (Δa) of the three basins are 1.87, 1.35, and 2.37 in Hareer, Hijran, and Dwaine basins, respectively. It was observed that the shape of Hareer and Shakrook anticlines has a significant impact on the main trunk of the channel. Therefore, when an anticline and syncline are close to each other (due to thrust faulting), then the hierarchical anomaly increases because the river trunk receives a lot of first-order streams, e.g., in Dwaine and Hijran basins. The lateral growth in the eastern part of Safin anticline had caused increasing of the Δa. The increased hierarchical anomaly index is attributed to the existence of faults and lineaments, which represent weakness zones. The hypsometric curves of the three basins have a typical shape of old stage with rejuvenation in their central and terminal portions which is changed into mature stage, most probably due to the local uplift which is caused by normal, thrust, and strike–slip (oblique) faults which exist in the study area and the near surroundings. The Bs and Hat values in Hareer, Dwaine, and Hijran basins indicate that the basins exhibit low, medium, and high tectonic activity, respectively.
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| 11. |
- Furtula, Vedran, 1981, et al.
(författare)
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Waveguide Bandpass Filters for Millimeter-Wave Radiometers
- 2013
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Ingår i: Journal of Infrared, Millimeter, and Terahertz Waves. - : Springer Science and Business Media LLC. - 1866-6892 .- 1866-6906. ; 34:12, s. 824-836
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Tidskriftsartikel (refereegranskat)abstract
- A fundamental requirement for most mm-wave heterodyne receivers is the rejection of the input image signal which is located close to the local oscillator frequency. For this purpose we use a bandpass filter, which for heterodyne receivers is also called an image rejection filter. In this paper we present a systematic approach to the design of a waveguide bandpass filter with a passband from 100 to 110 GHz and upper rejection bandwidth in the range from 113 to 145 GHz. We consider two non-tunable filter configurations: the first one is relatively selective with 11 sections (poles) whereas the second one is simpler with 5 sections. We used established design equations to propose an initial guess for the geometries of the filters, optimized the geometries, constructed the filters using two different milling methods, measured their transmission and reflection characteristics, and compared the measurements with numerical simulations. Measurements of both filters agree well with simulations in frequency response and rejection bandwidth. The insertion loss of the 11-pole filter is better than 10 dB and that of the 5-pole filter is better than 5 dB. The 11-pole filter has a sharper attenuation roll-off compared with the 5-pole filter. The upper out-of-band rejection is better than 40 dB up to 145 GHz for the 11-pole filter and up to 155 GHz for the 5-pole filter.
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| 12. |
- Ismael, Adnan A., et al.
(författare)
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Predicting the discharge coefficient of oblique cylindrical weir using neural network techniques
- 2021
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Ingår i: Arabian Journal of Geosciences. - : Springer. - 1866-7511 .- 1866-7538. ; 14:16
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Tidskriftsartikel (refereegranskat)abstract
- Cylindrical weir shapes offer a steady-state overflow pattern, where the type of weirs can offer a simple design and provide the ease-to-pass floating debris. This study considers a coefficient of discharge (Cd) prediction for oblique cylindrical weir using three diameters, the first is of D1 = 0.11 m, the second is of D2 = 0.09 m, and the third is of D3 = 0.06.5 m, and three inclination angles with respect to channel axis, the first is of θ1 = 90 ͦ, the second is of θ2 = 45 ͦ, and the third is of θ3 = 30 ͦ. The Cd values for total of 56 experiments are estimated by using the radial basis function network (RBFN), in addition of comparing that with the back-propagation neural network (BPNN) and cascade-forward neural network (CFNN). Root mean square error (RMSE), mean square error (MSE), and correlation coefficient (CC) statics are used as metrics measurements. The RBFN attained superior performance comparing to the other neural networks of BPNN and CFNN. It is found that, for the training stage, the RBFN network benchmarked very small RMSE and MSE values of 1.35E-12 and 1.83E-24, respectively and for the testing stage, it also could benchmark very small RMSE and MSE values of 0.0082 and 6.80E-05, respectively.
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| 13. |
- Johansson, Jessica, 1977-, et al.
(författare)
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Decreased binding capacity (Bmax) of muscarinic acetylcholine receptors in fibroblasts from boys with attention-deficit/hyperactivity disorder (ADHD)
- 2013
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Ingår i: ADHD Attention Deficit and Hyperactivity Disorders. - Berlin, Germany : Springer Berlin/Heidelberg. - 1866-6116 .- 1866-6647. ; 5:3, s. 267-271
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Tidskriftsartikel (refereegranskat)abstract
- Monoaminergic dysregulation is implicated in attention-deficit/hyperactivity disorder (ADHD), and methylphenidate and amphetamines are the most frequently prescribed pharmacological agents for treating ADHD. However, it has recently been proposed that the core symptoms of the disorder might be due to an imbalance between monoaminergic and cholinergic systems. In this study, we used fibroblast cell homogenates from boys with and without ADHD as an extraneural cell model to examine the cholinergic receptor density, that is, muscarinic acetylcholine receptors (mAChRs). We found that the binding capacity (Bmax) of [³H] Quinuclidinyl benzilate (³H-QNB) to mAChRs was decreased by almost 50 % in the children with ADHD (mean = 30.6 fmol/mg protein, SD = 25.6) in comparison with controls [mean = 63.1 fmol/mg protein, SD = 20.5, p ≤ 0.01 (Student's unpaired t test)]. The decreased Bmax indicates a reduced cholinergic receptor density, which might constitute a biomarker for ADHD. However, these preliminary findings need to be replicated in larger ADHD and comparison cohorts
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| 14. |
- Johnson, Mats, 1956, et al.
(författare)
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Fatty acids in ADHD: plasma profiles in a placebo-controlled study of Omega 3/6 fatty acids in children and adolescents.
- 2012
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Ingår i: Attention Deficit and Hyperactivity Disorders. - : Springer Science and Business Media LLC. - 1866-6116 .- 1866-6647. ; 4:4, s. 199-204
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to assess baseline levels and changes in plasma fatty acid profiles in children and adolescents with ADHD, in a placebo-controlled study with Omega 3/6 supplementation, and to compare with treatment response. Seventy-five children and adolescents aged 8-18years with DSM-IV ADHD were randomized to 3months of Omega 3/6 (Equazen eye q) or placebo, followed by 3months of open phase Omega 3/6 for all. n-3, n-6, n-6/n-3 ratio, EPA and DHA in plasma were measured at baseline, 3 and 6months. Subjects with more than 25% reduction in ADHD symptoms were classified as responders. At baseline, no significant differences in mean fatty acid levels were seen across active/placebo groups or responder/non-responder groups. The 0-3month changes in all parameters were significantly greater in the active group (p<0.01). Compared to non-responders, the 6-month responders had significantly greater n-3 increase at 3months and decrease in n-6/n-3 ratio at 3 and 6months (p<0.05). Omega 3/6 supplementation had a clear impact on fatty acid composition of plasma phosphatidyl choline in active versus placebo group, and the fatty acid changes appear to be associated with treatment response. The most pronounced and long-lasting changes for treatment responders compared to non-responders were in the n-6/n-3 ratio.
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| 15. |
- Nyström, Olle, 1979, et al.
(författare)
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Optics Design and Verificatgion for the APEX Swedish Heterodyne Facility Instrument (SHeFI)
- 2009
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Ingår i: Journal of Infrared, Millimeter, and Terahertz Waves. - : Springer Science and Business Media LLC. - 1866-6892 .- 1866-6906. ; 30:7, s. 746-761
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, we present the design and verification of the optics of the Swedish Heterodyne Facility Instrument (SHeFI) receiver installed in the Atacama Pathfinder EXperiment (APEX) telescope during spring 2008. SHeFI is located in the Nasmyth instrumentation Cabin A (NCA). The receiver has been designed to have 6 frequency channels, of which four receiver channels have been built, and characterized: 211-275 GHz(Band 1), 275-370 GHz (Band 2), 385-500 GHz (Band 3), and 1250-1390 GHz (Band T2). Bands 1, 2, and T2 are installed at the telescope and are currently in operation. The optical design is driven by the requirement of frequency independent illumination of the secondary with -12 dB edge taper for each frequency channel and the limitation (beam clearance through the Nasmyth tube and the elevation encoder) imposed by the receiver position in the NCA. This paper describes the design approach, optimization, and verification of the optical system, coupling each individual receiving beam to the common optics of the telescope.
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| 16. |
- Sissakian, Varoujan K., et al.
(författare)
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Safeen anticline: a complicated structure and its negative impact on oil exploration, Iraqi Kurdistan Region
- 2022
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Ingår i: Arabian Journal of Geosciences. - : Springer Nature. - 1866-7511 .- 1866-7538. ; 15
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Tidskriftsartikel (refereegranskat)abstract
- Safeen anticline is one of the most complicated anticlines in Iraqi Kurdistan Region (IKR), with NW–SE trend. Structurally, the anticline is truncated by different types of faults; some of them are deep-seated faults, which have complicated the subsurface form of the anticline. The anticline includes two domes with two parasitic anticlines and synclines along both limbs. Moreover, two hanging synclines exist northeastwards and one southwestwards. Six possible deep seated transversal faults may occur along the anticline, dissecting the anticline in NE–SW trend and extending northeastwards and southwestwards. Moreover, the deep-seated faults dissect many anticlines on both sides of the Safeen anticline. The deep-seated faults have contributed to the complexity of the anticline, as compared to other anticlines in the Zagros Fold–Thrust Belt, especially inside IKR, and have negative impact to the oil exploration activities in the anticline. Therefore, the drilled Safeen Oil well 01 has missed the target. We have used satellite images from land viewer website + Terraincognita app to study the structural style of the anticline, and to recognize different structural features. Field investigation was carried out to check the interpreted data.
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| 17. |
- Sulaiman, Sadeq Oleiwi, et al.
(författare)
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Evaluation of sediment transport empirical equations : case study of the Euphrates River West Iraq
- 2021
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Ingår i: Arabian Journal of Geosciences. - : Springer. - 1866-7511 .- 1866-7538. ; 14:10
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Tidskriftsartikel (refereegranskat)abstract
- Sediment transport in rivers is an important and complex process. It is very important to know the nature and quantities of sediments transported in course of rivers to achieve prudent water management. Due to the presence of most of the important projects on or near the banks of the river in the study area, so there is always a fear that these projects will be affected by the processes of erosion, transport, and sedimentation among the decision makers. Therefore, there is a need to develop our knowledge of the suitable equations that can be applied with acceptable accuracy to obtain satisfactory results for monitoring the processes of erosion, sedimentation, and transport that occur in River path to monitor and anticipate the changes taking place in the areas of the riverbanks. This study was carried out to check the reliability of different sediment transport formulas using data collected from the Euphrates River at the thermal power station in Al Anbar province, Iraq. The study also aimed to select the best formula for this site. Hydrological data have been collected. These were used for computing the total sediment load in the river at a specified cross-section using common sediment transport formulas ascribed to Ackers-White, Bagnold, Yang, Colby, Shen and Hung, and Engelund-Hansen. The performance of these formulas was assessed based on the accuracy of the predictions of the observed sediment load within a limited discrepancy ratio. The evaluations showed that the Engelund-Hansen formula represented the best formula for this river reach.
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| 18. |
- Zhang, Xia, 1980, et al.
(författare)
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Design of 50-70 GHz Planar Wideband Bandpass Filter on Liquid Crystal Polymer Substrate
- 2009
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Ingår i: Journal of Infrared, Millimeter, and Terahertz Waves. - : Springer Science and Business Media LLC. - 1866-6892 .- 1866-6906. ; 30:2, s. 183-189
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, the authors propose a novel and compact 50-70 GHz planar microstrip bandpass filter, possessing sharp-rejection, low insertion-loss and wide-band characteristics, based on Liquid Crystal Polymer (LCP) substrates. The filter is fabricated on LCP substrates by using standard processing technologies. The proposed filter exhibits a return loss level better than 10 dB, an insertion loss of 5 dB and a 3-dB bandwidth of 30%. The measured and simulated results show good agreement, proving that LCPs are potential and very promising materials for flexible millimeter-wave substrate applications.
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| 19. |
- Gustafsson, Peik, et al.
(författare)
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Motor function and perception in children with neuropsychiatric and conduct problems : results from a population based twin study
- 2014
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Ingår i: Journal of Neurodevelopmental Disorders. - Stockholm : Karolinska Institutet, Dept of Medical Epidemiology and Biostatistics. - 1866-1947 .- 1866-1955.
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Children with early symptomatic psychiatric disorders such as Attention-Deficit/Hyperactivity Disorder (ADHD) and Autism Spectrum Disorder (ASD) have been found to have high rates of motor and/or perception difficulties. However, there have been few large-scale studies reporting on the association between Conduct Disorder (CD) and motor/perception functions. The aim of the present study was to investigate how motor function and perception relate to measures of ADHD, ASD, and CD. METHODS: Parents of 16,994 Swedish twins (ages nine and twelve years) were interviewed using the Autism-Tics, ADHD and other Comorbidities inventory (A-TAC), which has been validated as a screening instrument for early onset child psychiatric disorders and symptoms. Associations between categorical variables of scoring above previously validated cut-off values for diagnosing ADHD, ASD, and CD on the one hand and motor and/or perception problems on the other hand were analysed using cross-tabulations, and the Fisher exact test. Associations between the continuous scores for ADHD, ASD, CD, and the subdomains Concentration/Attention, Impulsiveness/Activity, Flexibility, Social Interaction and Language, and the categorical factors age and gender, on the one hand, and the dependent dichotomic variables Motor control and Perception problems, on the other hand, were analysed using binary logistic regression in general estimated equation models. RESULTS: Male gender was associated with increased risk of Motor control and/or Perception problems. Children scoring above the cut-off for ADHD, ASD, and/or CD, but not those who were 'CD positive' but 'ADHD/ASD negative', had more Motor control and/or Perception problems, compared with children who were screen-negative for all three diagnoses. In the multivariable model, CD and Impulsiveness/Activity had no positive associations with Motor control and/or Perception problems. CONCLUSIONS: CD symptoms or problems with Impulsiveness/Activity were associated with Motor control or Perception problems only in the presence of ASD symptoms and/or symptoms of inattention. Our results indicate that children with CD but without ASD or inattention do not show a deviant development of motor and perceptual functions. Therefore, all children with CD should be examined concerning motor control and perception. If problems are present, a suspicion of ADHD and/or ASD should be raised.
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| 20. |
- Kraus, Ludwig, 1955-, et al.
(författare)
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Changes in the use of tobacco, alternative tobacco products, and tobacco alternatives in Germany
- 2022
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Ingår i: Deutsches Ärzteblatt International. - : Deutscher Arzte-Verlag GmbH. - 1866-0452. ; 119:31-32, s. 535-541
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Tidskriftsartikel (refereegranskat)abstract
- Background: Due to the increasing use of alternative tobacco products (waterpipes, heat-not-burn) and tobacco alternatives (e-cigarettes), we studied recent changes in the prevalence of conventional tobacco use and alternative products.Methods: Data come from ten waves of the Epidemiological Survey of Substance Abuse (ESA) from 1995 to 2021, with representative samples collected via paper-pencil questionnaires, telephone interviews, or online. We compared the prevalence of conventional tobacco use and alternative products by gender and age (18–24, 25–39, 40–59 years).Results: In all age groups, the use of conventional tobacco products decreased. The prevalence of the exclusive use of one of the three alternative products differed statistically significantly between age groups and in 2021 was higher for ages 18–24 (females: 11.1%, males: 12.4%) compared to ages 25–39 (females: 2.9%; males: 4.9%) and ages 40–59 (females: 1.4%; males: 2.0%). The use of alternative products was mainly due to the exclusive use of waterpipes among individuals aged 18 to 24 and 25 to 39 and the exclusive use of e-cigarettes among individuals aged 40 to 59.Conclusions: The higher prevalence of alternative product use among young adults implies a turning point that needs to be considered in prevention. Because of the addictive potential of these products, young adults can be expected to maintain their use into middle and older adulthood. There is a need to monitor the use of alternative products, identify the risks associated with them, and develop effective prevention and cessation interventions for adults.
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| 21. |
- Rauschert, Christian, et al.
(författare)
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The Use of Psychoactive Substances in Germany : Findings from the Epidemiological Survey of Substance Abuse 2021
- 2022
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Ingår i: Deutsches Ärzteblatt International. - : Deutscher Arzte-Verlag GmbH. - 1866-0452. ; 119:31-32, s. 527-534
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Tidskriftsartikel (refereegranskat)abstract
- Background: Monitoring the use of psychoactive substances and substance-related problems in the population allows for the assessment of prevalence and associated health and social consequences.Methods: The data are derived from the Epidemiological Survey of Substance Abuse (ESA) 2021 (n = 9046, 18–64 years). We estimated prevalence rates of the use of tobacco, alcohol, illegal drugs, and psychoactive medications, as well as the prevalence rates of their problematic use (indicating dependence) using screening instruments, and extrapolated the results to the resident population (N = 51 139 451).Results: Alcohol was the most frequently used substance, with a 30-day prevalence of 70.5% (36.1 million people), followed by non-opioid analgesic drugs (47.4%; 24.2 million) and conventional tobacco products (22.7%; 11.6 million). E-cigarettes were used by 4.3% (2.2 million) and heat-not-burn products by 1.3% (665 000). Among illegal drugs (12-month prevalence), cannabis was the most frequently used (8.8%; 4.5 million), followed by cocaine/crack (1.6%; 818 000) and amphetamine (1.4%; 716 000). Rates of problematic use among the study participants were 17.6% for alcohol (9.0 million), 7.8% for tobacco (4.0 million), 5.7% for psychoactive medications (2.9 million), and 2.5% for cannabis (1.3 million).Conclusion: The consumption of psychoactive substances continues to be widespread in Germany. In view of the imminent legal changes, the high prevalence of cannabis use and its problematic use need to be taken into consideration.
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| 22. |
- Falck-Ytter, Terje, et al.
(författare)
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Eye tracking in early autism research
- 2013
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Ingår i: Journal of Neurodevelopmental Disorders. - : Springer Science and Business Media LLC. - 1866-1955 .- 1866-1947. ; 5, s. 28-
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Forskningsöversikt (refereegranskat)abstract
- Eye tracking has the potential to characterize autism at a unique intermediate level, with links 'down' to underlying neurocognitive networks, as well as 'up' to everyday function and dysfunction. Because it is non-invasive and does not require advanced motor responses or language, eye tracking is particularly important for the study of young children and infants. In this article, we review eye tracking studies of young children with autism spectrum disorder (ASD) and children at risk for ASD. Reduced looking time at people and faces, as well as problems with disengagement of attention, appear to be among the earliest signs of ASD, emerging during the first year of life. In toddlers with ASD, altered looking patterns across facial parts such as the eyes and mouth have been found, together with limited orienting to biological motion. We provide a detailed discussion of these and other key findings and highlight methodological opportunities and challenges for eye tracking research of young children with ASD. We conclude that eye tracking can reveal important features of the complex picture of autism.
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| 23. |
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| 24. |
- de Vries, Petrus J, et al.
(författare)
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Natural clusters of tuberous sclerosis complex (TSC)-associated neuropsychiatric disorders (TAND) : new findings from the TOSCA TAND research project
- 2020
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Ingår i: Journal of Neurodevelopmental Disorders. - : Springer Science and Business Media LLC. - 1866-1955 .- 1866-1947. ; 12:1, s. 24-24
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Tuberous sclerosis complex (TSC)-associated neuropsychiatric disorders (TAND) have unique, individual patterns that pose significant challenges for diagnosis, psycho-education, and intervention planning. A recent study suggested that it may be feasible to use TAND Checklist data and data-driven methods to generate natural TAND clusters. However, the study had a small sample size and data from only two countries. Here, we investigated the replicability of identifying natural TAND clusters from a larger and more diverse sample from the TOSCA study.METHODS: As part of the TOSCA international TSC registry study, this embedded research project collected TAND Checklist data from individuals with TSC. Correlation coefficients were calculated for TAND variables to generate a correlation matrix. Hierarchical cluster and factor analysis methods were used for data reduction and identification of natural TAND clusters.RESULTS: A total of 85 individuals with TSC (female:male, 40:45) from 7 countries were enrolled. Cluster analysis grouped the TAND variables into 6 clusters: a scholastic cluster (reading, writing, spelling, mathematics, visuo-spatial difficulties, disorientation), a hyperactive/impulsive cluster (hyperactivity, impulsivity, self-injurious behavior), a mood/anxiety cluster (anxiety, depressed mood, sleep difficulties, shyness), a neuropsychological cluster (attention/concentration difficulties, memory, attention, dual/multi-tasking, executive skills deficits), a dysregulated behavior cluster (mood swings, aggressive outbursts, temper tantrums), and an autism spectrum disorder (ASD)-like cluster (delayed language, poor eye contact, repetitive behaviors, unusual use of language, inflexibility, difficulties associated with eating). The natural clusters mapped reasonably well onto the six-factor solution generated. Comparison between cluster and factor solutions from this study and the earlier feasibility study showed significant similarity, particularly in cluster solutions.CONCLUSIONS: Results from this TOSCA research project in an independent international data set showed that the combination of cluster analysis and factor analysis may be able to identify clinically meaningful natural TAND clusters. Findings were remarkably similar to those identified in the earlier feasibility study, supporting the potential robustness of these natural TAND clusters. Further steps should include examination of larger samples, investigation of internal consistency, and evaluation of the robustness of the proposed natural clusters.
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| 25. |
- Johansson, Viktoria, et al.
(författare)
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Medications for attention-deficit/hyperactivity disorder in individuals with or without coexisting autism spectrum disorder : analysis of data from the Swedish prescribed drug register
- 2020
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Ingår i: Journal of Neurodevelopmental Disorders. - : BioMed Central. - 1866-1955 .- 1866-1947. ; 12:1
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Clinical studies found that medication for attention-deficit/hyperactivity disorder (ADHD) is effective in coexisting autism spectrum disorder (ASD), but current research is based on small clinical studies mainly performed on children or adolescents. We here use register data to examine if individuals with ADHD and coexisting ASD present differences in the prescribing patterns of ADHD medication when compared to individuals with pure ADHD.METHODS: Data with information on filled prescriptions and diagnoses was retrieved from the Swedish Prescribed Drug Register and the National Patient Register. We identified 34,374 individuals with pure ADHD and 5012 individuals with ADHD and coexisting ASD, aged between 3 and 80 years. The first treatment episode with ADHD medications (≥ 2 filled prescriptions within 90 days) and daily doses of methylphenidate during a 3-year period was measured. Odds ratios (ORs) were calculated for the likelihood of being prescribed ADHD medication in individuals with and without ASD and Wilcoxon rank-sum test was used to compare group differences in dose per day.RESULTS: Individuals with ADHD and coexisting ASD were less likely to start continuous treatment with ADHD medication (ADHD 80.5%; ADHD with ASD 76.2%; OR, 0.80; 95% confidence interval, 0.75-0.86), were less likely to be prescribed methylphenidate, and were more commonly prescribed second line treatments such as dexamphetamine, amphetamine, or modafinil. No group difference was observed for atomoxetine. In adults with ADHD and coexisting ASD, methylphenidate was prescribed in lower daily doses over three years as compared to individuals with pure ADHD.CONCLUSIONS: The findings indicate that there are differences in the medical treatment of individuals with or without ASD. If these differences are due to different medication responses in ASD or due to other factors such as clinicians' perceptions of medication effects in patients with ASD, needs to be further studied.
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| 26. |
- Lilja, Maria, et al.
(författare)
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The effect of autistic traits on response to and side-effects of pharmacological ADHD treatment in children with ADHD : results from a prospective clinical cohort
- 2022
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Ingår i: Journal of Neurodevelopmental Disorders. - : BioMed Central. - 1866-1955 .- 1866-1947. ; 14:1
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Attention deficit hyperactivity disorder (ADHD) is a common childhood behavioral condition that globally affects an average of around 5% of children and is associated with several adverse life outcomes. Comorbidity with autism spectrum disorder (ASD) is highly prevalent. Pharmacological treatment for ADHD symptoms has been shown to be effective. However, the prevailing perception is that children with ADHD and concomitant ASD symptoms report poorer efficacy and more side effects. This has been supported by studies on this population, but prospective studies directly comparing children with ADHD and different levels of ASD symptoms are lacking. We aimed to assess if children with ADHD and concomitant ASD symptoms differ regarding effects and side-effects of pharmacological ADHD treatment compared to children with ADHD without ASD traits. This is to our knowledge the second study to directly compare the effect of ADHD medication between ADHD patients with different levels of ASD symptoms.METHODS: In a non-randomized, observational, prospective cohort study, 323 patients aged 6 to 17 years who were diagnosed with ADHD and starting pharmacological treatment were divided into two groups: one with high level of ASD symptoms (ASD group, N=71) and one with low level of ASD symptoms (non-ASD group, N = 252). Treatment outcome was measured as ADHD symptoms, and evaluated using the Swanson, Nolan and Pelham Teacher and Parent ADHD rating scale-version IV (SNAP-IV). Side-effects were evaluated using the Pediatric Side Effects Checklist (P-SEC), at 3 months follow-up.RESULTS: From baseline to 3 months, there was no significant difference in neither treatment effect nor number of clinically significant adverse events experienced between the ASD group and the non-ASD group.CONCLUSIONS: Our results did not implicate that ADHD patients with concomitant ASD symptoms have decreased treatment effect of ADHD medication than patients with ADHD without concomitant ASD symptoms. Neither did the results support that ADHD patients with ASD symptoms experienced significantly more side-effects than ADHD patients without ASD symptoms. Although, we did not analyze different medications separately, this is in line with the only previous study directly comparing methylphenidate treatment in children with or without ASD.
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| 27. |
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| 28. |
- Song, J., et al.
(författare)
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Clinical characteristics and long-term neurodevelopmental outcomes of leukomalacia in preterm infants and term infants: a cohort study
- 2023
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Ingår i: Journal of Neurodevelopmental Disorders. - 1866-1947 .- 1866-1955. ; 15:1
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundLeukomalacia is a serious form of neonatal brain injury that often leads to neurodevelopmental impairment, and studies on neonatal leukomalacia and its long-term outcomes are lacking. The aim of this study was to analyze the clinical manifestations, imaging features, and long-term neurodevelopmental outcomes in preterm infants and term infants with leukomalacia.MethodsNewborns diagnosed with leukomalacia by head magnetic resonance imaging (MRI) and who were admitted to intensive care units from January 2015 to June 2020 were enrolled. All infants were followed up to June 2022 (2-7 years old), and their neurodevelopmental outcomes were evaluated. The clinical data and long- term outcomes of preterm infants and term infants was analyzed by Chi-square tests.ResultsA total of 218 surviving infants with leukomalacia including 114 preterm infants and 104 term infants completed the follow-up. The major typesof leukomalacia on MRI were periventricular leukomalacia in the preterm group and subcortical cystic leukomalacia in the term group, respectively (& chi;(2) = 55.166; p < 0.001). When followed up to 2-7 years old, the incidence of neurodevelopmental impairment in the preterm group and term group was not significantly different (& chi;(2) = 0.917; p = 0.338). However, the incidence of cerebral palsy (CP) in the preterm group was significantly higher (& chi;(2) = 4.896; p = 0.027), while the incidence of intellectual disability (ID) (& chi;(2) = 9.445; p = 0.002), epilepsy (EP) (& chi;(2) = 23.049; p < 0.001), and CP combined with ID andEP (& chi;(2) = 4.122; p = 0.042) was significantly lower than that in the term group.ConclusionsPeriventricular leukomalacia mainly occurred in preterm infants while subcortical cystic leukomalacia was commonly seen in term infants. Although the long-term neurodevelopmental outcomes of leukomalacia were both poor, preterm infants were more prone to CP, while term infants were more prone to ID, EP, and the combination of CP with ID and EP.
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| 29. |
- Harrison, S.P., et al.
(författare)
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The Reading Palaeofire Database: an expanded global resource to document changes in fire regimes from sedimentary charcoal records
- 2022
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Ingår i: Earth System Science Data. - : Copernicus GmbH. - 1866-3508 .- 1866-3516. ; 14:3, s. 1109-1124
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Tidskriftsartikel (refereegranskat)abstract
- Sedimentary charcoal records are widely used to reconstruct regional changes in fire regimes through time in the geological past. Existing global compilations are not geographically comprehensive and do not provide consistent metadata for all sites. Furthermore, the age models provided for these records are not harmonised and many are based on older calibrations of the radiocarbon ages. These issues limit the use of existing compilations for research into past fire regimes. Here, we present an expanded database of charcoal records, accompanied by new age models based on recalibration of radiocarbon ages using IntCal20 and Bayesian age-modelling software. We document the structure and contents of the database, the construction of the age models, and the quality control measures applied. We also record the expansion of geographical coverage relative to previous charcoal compilations and the expansion of metadata that can be used to inform analyses. This first version of the Reading Palaeofire Database contains 1676 records (entities) from 1480 sites worldwide. The database (RPDv1b - Harrison et al., 2021) is available at 10.17864/1947.000345. © 2022 Sandy P. Harrison et al.
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| 30. |
- Bang, Peter, et al.
(författare)
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Sensory symptoms associated with autistic traits and anxiety levels in children aged 6-11 years
- 2024
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Ingår i: Journal of Neurodevelopmental Disorders. - : BMC. - 1866-1947. ; 16:1
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundAutism spectrum conditions (ASC) and quantitative autistic traits (QATs) are associated with sensory symptoms, which may contribute to anxiety and adversely affect social and cognitive development. Although sensory symptoms can occur across all senses, the relative roles of specific sensory modalities as contributors to the autistic phenotype and to anxiety are not well understood. The objective of this study was to examine which sensory symptoms were most predictive of high anxiety.MethodsWe recruited 257 female primary caregivers of children aged 6 to 11 years (49% girls) to a questionnaire study comprising parent-report measures for classical QATs (social, communicative, and rigid), autism-related sensorimotor symptoms (visual, auditory, tactile, olfactory, gustatory, vestibular, proprioceptive, and motor), and anxiety symptoms. First, Bayesian stochastic search variable selection (SSVS) was used to identify the most probable sensorimotor predictors of specific QATs as well as diagnosed ASC. Then, the selected predictors were used in another SSVS, using anxiety symptoms as a dependent variable, to identify which of the autism-relevant sensorimotor symptoms were most robustly predictive of anxiety. Finally, the effect sizes of anxiety-related sensory symptoms were estimated with linear regressions.ResultsWe found that auditory symptoms and motor difficulties were most predictive of ASC diagnosis. Developmental motor difficulties were also strongly related to all individual QATs, whereas auditory symptoms were more selectively predictive of rigid traits. Tactile symptoms robustly predicted social interaction QATs, and proprioceptive symptoms predicted communicative QATs. Anxiety outcomes were most strongly predicted by difficulties with auditory and olfactory processing.ConclusionsThe results support the clinical importance of being alert to complaints about sounds and hearing in neurodevelopmental populations, and that auditory processing difficulties may be evaluated as an early marker of poor mental health in children with and without diagnosed autism. Olfactory processing differences appeared to be an anxiety marker less strongly associated with ASC or QATs, while motor difficulties were highly autism-relevant but not equally strongly associated with anxiety outcomes. We suggest that future studies may focus on the mechanisms and consequences of neurodevelopmental central auditory processing dysfunction and its potential relationship to anxiety disorders.
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