| 1. |
- Ademuyiwa, Adesoji O., et al.
(author)
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Determinants of morbidity and mortality following emergency abdominal surgery in children in low-income and middle-income countries
- 2016
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In: BMJ Global Health. - : BMJ Publishing Group Ltd. - 2059-7908. ; 1:4
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Journal article (peer-reviewed)abstract
- Background: Child health is a key priority on the global health agenda, yet the provision of essential and emergency surgery in children is patchy in resource-poor regions. This study was aimed to determine the mortality risk for emergency abdominal paediatric surgery in low-income countries globally.Methods: Multicentre, international, prospective, cohort study. Self-selected surgical units performing emergency abdominal surgery submitted prespecified data for consecutive children aged <16 years during a 2-week period between July and December 2014. The United Nation's Human Development Index (HDI) was used to stratify countries. The main outcome measure was 30-day postoperative mortality, analysed by multilevel logistic regression.Results: This study included 1409 patients from 253 centres in 43 countries; 282 children were under 2 years of age. Among them, 265 (18.8%) were from low-HDI, 450 (31.9%) from middle-HDI and 694 (49.3%) from high-HDI countries. The most common operations performed were appendectomy, small bowel resection, pyloromyotomy and correction of intussusception. After adjustment for patient and hospital risk factors, child mortality at 30 days was significantly higher in low-HDI (adjusted OR 7.14 (95% CI 2.52 to 20.23), p<0.001) and middle-HDI (4.42 (1.44 to 13.56), p=0.009) countries compared with high-HDI countries, translating to 40 excess deaths per 1000 procedures performed.Conclusions: Adjusted mortality in children following emergency abdominal surgery may be as high as 7 times greater in low-HDI and middle-HDI countries compared with high-HDI countries. Effective provision of emergency essential surgery should be a key priority for global child health agendas.
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| 2. |
- Latif, Umar, et al.
(author)
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In situ growth of nickel ammonium phosphate ribbons on nickel foam for supercapacitor applications
- 2023
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In: Journal of Energy Storage. - : Elsevier. - 2352-152X .- 2352-1538. ; 73:Part B
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Journal article (peer-reviewed)abstract
- We report the in-situ growth of the nickel ammonium phosphate (NAP) ribbons on nickel (Ni) foam in a single step process using hydrothermal approach. The morphology, structure and elemental analysis of the NAP-ribbons grown on Ni foam were analyzed by scanning electron microscope (SEM), energy-dispersive x-ray analysis (EDX) and x-ray diffraction. The NAP-coated Ni foam sample was sonicated in ethanol and the obtained suspension was observed through AFM analysis to analyze the lateral dimensions of the NAP-ribbons. The obtained NAP ribbons powder was also characterized by x-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. Further, the NAP ribbons based electrodes were electrochemically characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and galvanostatic charge discharge analysis (GCD). NAP ribbons grown on Ni foam as electrodes achieved a specific capacitance (Csp) of 1196 Fg- 1 at 1 mVs- 1 and 1188 Fg- 1 at 1 Ag-1. The charge storage mechanism was identified and quantified by evaluating the CV data in 1-10 mVs- 1 scan rate range. It was established that at low scan rate the charge was dominantly stored by diffusion of electrolyte ions within the gaps of the NAP ribbons resulting in high energy density of 105.5 WhKg-1 at 1 Ag-1. NAP electrodes also demonstrated good cyclic stability by showing 92 % charge retention after 5000 cycles. A symmetric 2-elec-trode device comprised of NAP ribbons electrodes gave Csp of 309 Fg-1 at 1 mVs- 1 with energy density of 42.06 Wh/Kg and power density of 0.5 KW/Kg at 1 A/g current density, which is an exceptional for a symmetric supercapacitor device. The study confirms that NAP ribbons have a promising potential to be employed in the next-generation energy storage devices.
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| 3. |
- Latif, Umar, et al.
(author)
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Role of sulfur and phosphorous doping on the electrochemical performance of graphene oxide-based electrodes
- 2024
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In: Electrochimica Acta. - : Elsevier. - 0013-4686 .- 1873-3859. ; 497
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Journal article (peer-reviewed)abstract
- Heteroatom doping of graphene oxide (GO) with phosphorous (P), and sulfur (S) was studied. In-situ grown binder-free electrodes of these doped and un-doped GO systems were developed via hydrothermal process. S-GO, P-GO, PS-GO, and un-doped hydrothermally treated GO (H-GO) electrodes were thoroughly investigated through physical and electrochemical characterization. The PS-GO electrode, comprising P (10.90 at%), S (0.3 at%), C (45.54 at%), O (36.36 at%), and Ni (2.38 at%) atoms, exhibited a mixed morphology of a few hundred nanometers doped GO flakes and dissolved Ni foam nanorods. Electrochemical analysis showed, this mixed morphology stimulates the charge storage ability of the PS-GO electrode and achieved a high specific capacity of 1218 C/g, compared to 647 C/g for H-GO at 1 mV/s. Electrochemical analysis revealed, charge was primarily stored through the capacitive charge storage mechanism, where only surface atoms are solely responsible for developing a double layer or facilitating redox reactions between electrode atoms and electrolyte ions. Additionally, the PS-GO electrode demonstrated an energy density of 76.94 Wh/kg at 1 A/g, which is much closer to that of batteries. We anticipate that PS-GO has the potential to be utilized as electrode material in modern energy storage devices.
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| 4. |
- Raza, Mohsin Ali, et al.
(author)
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Synthesis and characterization of zinc aluminate electrodes for supercapacitor applications
- 2024
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In: Electrochimica Acta. - : Elsevier. - 0013-4686 .- 1873-3859. ; 475
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Journal article (peer-reviewed)abstract
- We report, for the first time, the thorough electrochemical characterization of zinc aluminate spinel. Four different stoichiometric composition of zinc aluminate (ZnAl1.5O3.25, ZnAl2O4, ZnAl2.87O5.30, and ZnAl4O7) were prepared by solution combustion method. The obtained powders after calcination at 1000 °C were characterized through scanning electron microscope (SEM), energy dispersive x-ray spectroscopy (EDX) and x-ray diffraction to analyze the morphology, elemental composition and structure, respectively, of the zinc aluminate compositions. The electrodes were prepared by coating slurry of zinc aluminate, carbon black and polyvinylidene fluoride on nickel foam in a ratio of 8:1:1. The electrochemical characterization was carried out by cyclic voltammetry (CV), galvanostatic charge discharge (GCD) and electrochemical impedance spectroscopy (EIS). ZnAl1.5O3.25 exhibited the highest specific capacity of 546 C/g at 1 mV/s and 336 C/g at 1 A/g, as appraised by CV and GCD analysis, respectively. EIS test revealed that ZnAl1.5O3.25 had the modest impedance value. The energy density value for ZnAl1.5O3.25 sample was 16.79 Wh/kg at 1 A/g with a power density of 179.9 W/kg. The as developed electrodes showed predominantly pseudo-capacitive charge storage mechanism.
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| 5. |
- Umer, Muhammad, et al.
(author)
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Analysis of STAR-RIS Assisted Downlink CoMP-NOMA Multi-Cell Networks under Nakagami-m Fading
- 2024
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In: IEEE Communications Letters. - : IEEE. - 1089-7798 .- 1558-2558. ; 28:5, s. 1009-1013
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Journal article (peer-reviewed)abstract
- In this letter, we conduct a thorough analytical assessment of a simultaneously transmitting and reflecting reconfigurable intelligent surface (STAR-RIS) assisted non-orthogonal multiple access (NOMA) enhanced coordinated multipoint (CoMP) multi-cell network under Nakagami-m fading. Using the central limit theorem (CLT) and moment-matching based Gamma approximation method, we derive the distributions of effective and cascaded channel gains. Subsequently, leveraging these results, we formulate tractable equations for ergodic rates and outage probabilities across all users in the network. Our analytical results correlate with the simulation results, affirming the efficacy of analytical methodology. Furthermore, the results demonstrate a significant performance improvement of STAR-RIS assisted CoMP-NOMA networks compared to conventional systems.
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| 6. |
- Iqbal, Mohsin, et al.
(author)
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Stair Geometry Inspired Ultra-Wideband Antenna with Simple Feeding Mechanism and Loaded by Circular-Slot for 5G Applications Over the V- and E-Bands
- 2022
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In: 2022 International Workshop On Antenna Technology (Iwat). - : Institute of Electrical and Electronics Engineers (IEEE). ; , s. 97-99
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Conference paper (peer-reviewed)abstract
- In this paper, a compact, low profile, geometrically simple, ultra-wideband and high gain antenna is designed for V-band and E-band applications. The proposed work is designed over the substrate material Rogers RT/duroid 5880 with dimensions of 15 mm x 15 mm x 0.79 mm. The proposed work operates over a wide band of 22 GHz for the V-band and 21 GHz for the E band. Moreover, the proposed work is compared to already published work to show the potential of the proposed work for the targeted frequency band. The results of the proposed work indicate that the antenna is a good candidate for future wireless communication systems in V and E band.
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| 7. |
- Jarchavi, Syed Muhammad Rizvi, et al.
(author)
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Compact Multi-Band Flexible Antenna for ISM, WLAN, Wi-Fi, and 5G sub-6-GHz Applications
- 2022
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In: 2022 3rd URSI Atlantic and Asia Pacific Radio Science Meeting, AT-AP-RASC 2022. - : Institute of Electrical and Electronics Engineers (IEEE).
-
Conference paper (peer-reviewed)abstract
- Design and analysis of a compact multi-band flexible antenna are presented here. The antenna is designed using the flexible substrate material Rogers 5880 and has a compact size of 18mmx18mmx0.254mm. The coplanar waveguide (CPW) fed radiator consists of a rectangular-shaped patch modified using a pair of rectangular slots to achieve the required bandwidth. Another smaller slot was etched in the radiator to achieve a lower resonance. The proposed design offers a multi-band functionality covering ISM, WLAN, Wi-Fi, and upper 5G sub6-GHz bands.
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| 8. |
- Mumtaz, Nadia, et al.
(author)
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An overview of violence detection techniques : current challenges and future directions
- 2023
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In: Artificial Intelligence Review. - Dordrecht : Springer Nature. - 0269-2821 .- 1573-7462. ; 56, s. 4641-4666
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Journal article (peer-reviewed)abstract
- The Big Video Data generated in today’s smart cities has raised concerns from its purposeful usage perspective, where surveillance cameras, among many others are the most prominent resources to contribute to the huge volumes of data, making its automated analysis adifcult task in terms of computation and preciseness. Violence detection (VD), broadly plunging under action and activity recognition domain, is used to analyze Big Video data for anomalous actions incurred due to humans. The VD literature is traditionally basedon manually engineered features, though advancements to deep learning based standalone models are developed for real-time VD analysis. This paper focuses on overview of deepsequence learning approaches along with localization strategies of the detected violence.This overview also dives into the initial image processing and machine learning-based VD literature and their possible advantages such as efciency against the current complex models. Furthermore,the datasets are discussed, to provide an analysis of the current models, explaining their pros and cons with future directions in VD domain derived from anin-depth analysis of the previous methods. © The Author(s), under exclusive licence to Springer Nature B.V. 2022.
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