| 11. |
- Hegazy, Mohamed-Elamir F., et al.
(författare)
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Terpenoid bio-transformations and applications via cell/organ cultures : a systematic review
- 2020
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Ingår i: Critical reviews in biotechnology. - : Informa UK Limited. - 0738-8551 .- 1549-7801. ; 40:1, s. 64-82
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Forskningsöversikt (refereegranskat)abstract
- Structurally diverse natural products are valued for their targeted biological activity. The challenge of working with such metabolites is their low natural abundance and complex structure, often with multiple stereocenters, precludes large-scale or unsophisticated chemical synthesis. Since select plants contain the enzymatic machinery necessary to produce specialized compounds, tissue cultures can be used to achieve key transformations for large-scale chemical and/or pharmaceutical applications. In this context, plant tissue-culture bio-transformations have demonstrated great promise in the preparation of pharmaceutical products. This review describes the capacity of cultured plant cells to transform terpenoid natural products and the specific application of such transformations over the past three decades (1988-2019).
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| 12. |
- Reda, Eman H., et al.
(författare)
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Comparative Study on the Essential Oils from Five Wild Egyptian Centaurea Species : Effective Extraction Techniques, Antimicrobial Activity and In-Silico Analyses
- 2021
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Ingår i: Antibiotics. - : MDPI AG. - 2079-6382. ; 10:3
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Tidskriftsartikel (refereegranskat)abstract
- The genus Centaurea is recognized in folk medicine for anti-inflammatory, anti-itch, antitussive, purgative, astringent, and tonic activities. To study the chemical determinant for antimicrobial activity essential oils (EOs), five Centaurea species were analyzed including: C. scoparia, C. calcitrapa, C. glomerata, C. lipii and C. alexandrina. Conventional hydro-distillation (HD) and microwave-assisted extraction (MAE), as new green technologies, were compared for the extraction of essential oils. GC/MS analysis identified 120 EOs including mostly terpenoid except from C. lipii and C. alexandrina in which nonterpenoids were the major constituents. Major terpenoids included spathulenol, caryophyllene oxide and alloaromadendrene oxide-2. To probe antibacterial activity, potential EO inhibitors of a bacterial type II DNA topoisomerase, DNA gyrase B were screened via an in silico molecular docking approach. Spathulenol and alloaromadendrene oxide-2 possessed the best binding affinity in the ATP- binding pocket of Gyrase B enzyme. Principal component analysis and agglomerative hierarchical clustering were used for sample classification and revealed that sesquiterpenes contributed the most for accessions classification. In vitro antimicrobial activity against Staphylococcus aureus, Escherichia coli and Aspergillus niger for all EOs were also evaluated. EOs from C. lipii, C. glomerata and C. calcitrapa exhibited significant MIC against S. aureus with an MIC value of 31.25 µg/mL.
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| 13. |
- Paz Duran, América, et al.
(författare)
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Bringing the Nature Futures Framework to life : creating a set of illustrative narratives of nature futures
- 2023
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Ingår i: Sustainability Science. - 1862-4065 .- 1862-4057.
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Tidskriftsartikel (refereegranskat)abstract
- To halt further destruction of the biosphere, most people and societies around the globe need to transform their relationships with nature. The internationally agreed vision under the Convention of Biological Diversity—Living in harmony with nature—is that “By 2050, biodiversity is valued, conserved, restored and wisely used, maintaining ecosystem services, sustaining a healthy planet and delivering benefits essential for all people”. In this context, there are a variety of debates between alternative perspectives on how to achieve this vision. Yet, scenarios and models that are able to explore these debates in the context of “living in harmony with nature” have not been widely developed. To address this gap, the Nature Futures Framework has been developed to catalyse the development of new scenarios and models that embrace a plurality of perspectives on desirable futures for nature and people. In this paper, members of the IPBES task force on scenarios and models provide an example of how the Nature Futures Framework can be implemented for the development of illustrative narratives representing a diversity of desirable nature futures: information that can be used to assess and develop scenarios and models whilst acknowledging the underpinning value perspectives on nature. Here, the term illustrative reflects the multiple ways in which desired nature futures can be captured by these narratives. In addition, to explore the interdependence between narratives, and therefore their potential to be translated into scenarios and models, the six narratives developed here were assessed around three areas of the transformative change debate, specifically, (1) land sparing vs. land sharing, (2) Half Earth vs. Whole Earth conservation, and (3) green growth vs. post-growth economic development. The paper concludes with an assessment of how the Nature Futures Framework could be used to assist in developing and articulating transformative pathways towards desirable nature futures.
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| 14. |
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| 15. |
- 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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| 16. |
- Alawi, Omer A., et al.
(författare)
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Heat transfer and hydrodynamic properties using different metal-oxide nanostructures in horizontal concentric annular tube : An optimization study
- 2021
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Ingår i: Nanomaterials. - : MDPI AG. - 2079-4991. ; 11:8
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Tidskriftsartikel (refereegranskat)abstract
- Numerical studies were performed to estimate the heat transfer and hydrodynamic properties of a forced convection turbulent flow using three-dimensional horizontal concentric annuli. This paper applied the standard k–ε turbulence model for the flow range 1 × 104 ≤ Re ≥ 24 × 103. A wide range of parameters like different nanomaterials (Al2O3, CuO, SiO2 and ZnO), different particle nanoshapes (spherical, cylindrical, blades, platelets and bricks), different heat flux ratio (HFR) (0, 0.5, 1 and 2) and different aspect ratios (AR) (1.5, 2, 2.5 and 3) were examined. Also, the effect of inner cylinder rotation was discussed. An experiment was conducted out using a field-emission scanning electron microscope (FE-SEM) to characterize metallic oxides in spherical morphologies. Nano-platelet particles showed the best enhancements in heat transfer properties, followed by nano-cylinders, nano-bricks, nano-blades, and nano-spheres. The maximum heat transfer enhancement was found in SiO2, followed by ZnO, CuO, and Al2O3, in that order. Meanwhile, the effect of the HFR parameter was insignificant. At Re = 24,000, the inner wall rotation enhanced the heat transfer about 47.94%, 43.03%, 42.06% and 39.79% for SiO2, ZnO, CuO and Al2O3, respectively. Moreover, the AR of 2.5 presented the higher heat transfer improvement followed by 3, 2, and 1.5.
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| 17. |
- Basuony, Mohamed A.K., et al.
(författare)
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Big data analytics of corporate internet disclosures
- 2022
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Ingår i: Accounting Research Journal. - : Emerald Group Publishing Limited. - 1030-9616 .- 1839-5465. ; 35:1, s. 4-20
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: This study aims to investigate the extent and characteristics of corporate internet disclosure via companies’ websites as well via social media and networks sites in the four leading English-speaking stock markets, namely, Australia, Canada, the UK and the USA.Design/methodology/approach: A disclosure index comprising a set of items that encompasses two facets of online disclosure, namely, company websites and social media sites, is used. This paper adopts a data science approach to investigate corporate internet disclosure practices among top listed firms in Australia, Canada, the UK and the USA.Findings: The results reveal the underlying relations between the determining factors of corporate disclosure, i.e. profitability, leverage, liquidity and firm size. Profitability in its own has no great effect on the degree of corporate internet disclosure whether via company websites or social media sites. Liquidity has an impact on the degree of disclosure. Firm size and leverage appear to be the most important factors driving better disclosure via social media. American companies tend to be on the cutting edge of technology when it comes to corporate disclosure.Practical implications: This paper provides new insights into corporate internet disclosure that will benefit all stakeholders with an interest in corporate reporting. Social media is an influential means of communication that can enable corporate office to get instant feedback enhancing their decision-making process.Originality/value: To the best of the authors’ knowledge, this study is amongst few studies of corporate disclosure via social media platforms. This study has adopted disclosure index incorporating social media as well as applying data science approach in disclosure in an attempt to unfold how accounting could benefit from data science techniques.
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| 18. |
- Fusai, Giuseppe Kito, et al.
(författare)
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Pancreatic surgery outcomes: multicentre prospective snapshot study in 67 countries
- 2023
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Ingår i: British Journal of Surgery. - : OXFORD UNIV PRESS. - 0007-1323 .- 1365-2168.
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Tidskriftsartikel (refereegranskat)abstract
- Background: Pancreatic surgery remains associated with high morbidity rates. Although postoperative mortality appears to have improved with specialization, the outcomes reported in the literature reflect the activity of highly specialized centres. The aim of this study was to evaluate the outcomes following pancreatic surgery worldwide. Methods: This was an international, prospective, multicentre, cross-sectional snapshot study of consecutive patients undergoing pancreatic operations worldwide in a 3-month interval in 2021. The primary outcome was postoperative mortality within 90 days of surgery. Multivariable logistic regression was used to explore relationships with Human Development Index (HDI) and other parameters. Results: A total of 4223 patients from 67 countries were analysed. A complication of any severity was detected in 68.7 percent of patients (2901 of 4223). Major complication rates (Clavien-Dindo grade at least IIIa) were 24, 18, and 27 percent, and mortality rates were 10, 5, and 5 per cent in low-to-middle-, high-, and very high-HDI countries respectively. The 90-day postoperative mortality rate was 5.4 per cent (229 of 4223) overall, but was significantly higher in the low-to-middle-HDI group (adjusted OR 2.88, 95 per cent c.i. 1.80 to 4.48). The overall failure-to-rescue rate was 21 percent; however, it was 41 per cent in low-to-middle-compared with 19 per cent in very high-HDI countries. Conclusion: Excess mortality in low-to-middle-HDI countries could be attributable to failure to rescue of patients from severe complications. The authors call for a collaborative response from international and regional associations of pancreatic surgeons to address management related to death from postoperative complications to tackle the global disparities in the outcomes of pancreatic surgery (NCT04652271; ISRCTN95140761).
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| 19. |
- Abba, Alia Besma, et al.
(författare)
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Copper and Zinc Removal from Wastewater Using Alum Sludge Recovered from Water Treatment Plant
- 2022
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Ingår i: Sustainability. - : MDPI. - 2071-1050. ; 14:16
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Tidskriftsartikel (refereegranskat)abstract
- The study aimed to determine Aluminum sludge composition and structure for its valorisation as an alternative natural material for heavy metals removal from wastewater for further reuse as treated water in different applications. The study was conducted to investigate the introduction of Al-bearing sludge composition. The physical and chemical properties were examined using X-ray diffraction tests (XRD), scanning electron microscope tests (SEM), Fourier-transform infrared tests (FTIR), and Brunauer-Emmett-Teller tests (BET). Furthermore, the heavy metal concentrations of synthetic wastewater were measured using the spectrophotometry method. The experimental procedure is based on testing different pH limits and amounts of aluminum sludge to find the optimum conditions for copper (Cu) and zinc (Zn) removal. The results demonstrated a high removal efficiency where its value reached up to 97.4% and 96.6% for Zn and Cu, respectively, in an acidic medium (pH = 6) using a relatively high amount of sludge (1400 mg). Nevertheless, a low efficiency was obtained in the strongly acidic medium (pH = 4) and a smaller sludge amount of about 480 mg.
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| 20. |
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