| 1. |
- Abdel-Hameed, Amal Mohamed, et al.
(författare)
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Estimation of Potato Water Footprint Using Machine Learning Algorithm Models in Arid Regions
- 2024
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Ingår i: Potato Research. - : Springer Nature. - 0014-3065 .- 1871-4528.
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Tidskriftsartikel (refereegranskat)abstract
- Precise assessment of water footprint to improve the water consumption and crop yield for irrigated agricultural efficiency is required in order to achieve water management sustainability. Although Penman-Monteith is more successful than other methods and it is the most frequently used technique to calculate water footprint, however, it requires a significant number of meteorological parameters at different spatio-temporal scales, which are sometimes inaccessible in many of the developing countries such as Egypt. Machine learning models are widely used to represent complicated phenomena because of their high performance in the non-linear relations of inputs and outputs. Therefore, the objectives of this research were to (1) develop and compare four machine learning models: support vector regression (SVR), random forest (RF), extreme gradient boost (XGB), and artificial neural network (ANN) over three potato governorates (Al-Gharbia, Al-Dakahlia, and Al-Beheira) in the Nile Delta of Egypt and (2) select the best model in the best combination of climate input variables. The available variables used for this study were maximum temperature (Tmax), minimum temperature (Tmin), average temperature (Tave), wind speed (WS), relative humidity (RH), precipitation (P), vapor pressure deficit (VPD), solar radiation (SR), sown area (SA), and crop coefficient (Kc) to predict the potato blue water footprint (BWF) during 1990–2016. Six scenarios (Sc1–Sc6) of input variables were used to test the weight of each variable in four applied models. The results demonstrated that Sc5 with the XGB and ANN model gave the most promising results to predict BWF in this arid region based on vapor pressure deficit, precipitation, solar radiation, crop coefficient data, followed by Sc1. The created models produced comparatively superior outcomes and can contribute to the decision-making process for water management and development planners.
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| 2. |
- Abdel-Hameed, Amal Mohamed, et al.
(författare)
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Winter Potato Water Footprint Response to Climate Change in Egypt
- 2022
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Ingår i: Atmosphere. - : MDPI. - 2073-4433. ; 13:7
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Tidskriftsartikel (refereegranskat)abstract
- The limited amount of freshwater is the most important challenge facing Egypt due to increasing population and climate change. The objective of this study was to investigate how climatic change affects the winter potato water footprint at the Nile Delta covering 10 governorates from 1990 to 2016. Winter potato evapotranspiration (ETC) was calculated based on daily climate variables of minimum temperature, maximum temperature, wind speed and relative humidity during the growing season (October–February). The Mann–Kendall test was applied to determine the trend of climatic variables, crop evapotranspiration and water footprint. The results showed that the highest precipitation values were registered in the northwest governorates (Alexandria followed by Kafr El-Sheikh). The potato water footprint decreased from 170 m3 ton−1 in 1990 to 120 m3 ton−1 in 2016. The blue-water footprint contributed more than 75% of the total; the remainder came from the green-water footprint. The findings from this research can help government and policy makers better understand the impact of climate change on potato crop yield and to enhance sustainable water management in Egypt’s major crop-producing regions to alleviate water scarcity.
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| 3. |
- Hagag, Naglaa M., et al.
(författare)
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Molecular Epidemiology and Evolutionary Analysis of Avian Influenza A(H5) Viruses Circulating in Egypt, 2019-2021
- 2022
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Ingår i: Viruses. - : MDPI AG. - 1999-4915. ; 14:8
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Tidskriftsartikel (refereegranskat)abstract
- The highly pathogenic avian influenza (HPAI) H5N8 virus was first detected in Egypt in late 2016. Since then, the virus has spread rapidly among different poultry sectors, becoming the dominant HPAI H5 subtype reported in Egypt. Different genotypes of the HPAI H5N8 virus were reported in Egypt; however, the geographic patterns and molecular evolution of the Egyptian HPAI H5N8 viruses are still unclear. Here, extensive epidemiological surveillance was conducted, including more than half a million samples collected from different poultry sectors (farms/backyards/live bird markets) from all governorates in Egypt during 2019-2021. In addition, genetic characterization and evolutionary analyses were performed using 47 selected positive H5N8 isolates obtained during the same period. The result of the conducted surveillance showed that HPAI H5N8 viruses of clade 2.3.4.4b continue to circulate in different locations in Egypt, with an obvious seasonal pattern, and no further detection of the HPAI H5N1 virus of clade 2.2.1.2 was observed in the poultry population during 2019-2021. In addition, phylogenetic and Bayesian analyses revealed that two major genotypes (G5 and G6) of HPAI H5N8 viruses were continually expanding among the poultry sectors in Egypt. Notably, molecular dating analysis suggested that the Egyptian HPAI H5N8 virus is the potential ancestral viruses of the European H5N8 viruses of 2020-2021. In summary, the data of this study highlight the current epidemiology, diversity, and evolution of HPAI H5N8 viruses in Egypt and call for continuous monitoring of the genetic features of the avian influenza viruses in Egypt.
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| 4. |
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| 5. |
- Duffy, Darragh, et al.
(författare)
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The ABCs of viral hepatitis that define biomarker signatures of acute viral hepatitis
- 2014
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Ingår i: Hepatology. - : Ovid Technologies (Wolters Kluwer Health). - 1527-3350 .- 0270-9139. ; 59:4, s. 1273-1282
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Tidskriftsartikel (refereegranskat)abstract
- Viral hepatitis is the leading cause of liver disease worldwide and can be caused by several agents, including hepatitis A (HAV), B (HBV), and C (HCV) virus. We employed multiplexed protein immune assays to identify biomarker signatures of viral hepatitis in order to define unique and common responses for three different acute viral infections of the liver. We performed multianalyte profiling, measuring the concentrations of 182 serum proteins obtained from acute HAV- (18), HBV- (18), and HCV-infected (28) individuals, recruited as part of a hospital-based surveillance program in Cairo, Egypt. Virus-specific biomarker signatures were identified and validation was performed using a unique patient population. A core signature of 46 plasma proteins was commonly modulated in all three infections, as compared to healthy controls. Principle component analysis (PCA) revealed a host response based upon 34 proteins, which could distinguish HCV patients from HAV- and HBV-infected individuals or healthy controls. When HAV and HBV groups were compared directly, 34 differentially expressed serum proteins allowed the separation of these two patient groups. A validation study was performed on an additional 111 patients, confirming the relevance of our initial findings, and defining the 17 analytes that reproducibly segregated the patient populations. Conclusions: This combined discovery and biomarker validation approach revealed a previously unrecognized virus-specific induction of host proteins. The identification of hepatitis virus specific signatures provides a foundation for functional studies and the identification of potential correlates of viral clearance. (Hepatology 2014;59:1273-1282)
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| 6. |
- Klionsky, Daniel J., et al.
(författare)
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Guidelines for the use and interpretation of assays for monitoring autophagy
- 2012
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Ingår i: Autophagy. - : Informa UK Limited. - 1554-8635 .- 1554-8627. ; 8:4, s. 445-544
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Forskningsöversikt (refereegranskat)abstract
- In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process vs. those that measure flux through the autophagy pathway (i.e., the complete process); thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from stimuli that result in increased autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field.
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| 7. |
- Amal, Mohamed, et al.
(författare)
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Differences and similarities of the internationalization processes of multinational companies from developed and emerging countries
- 2013
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Ingår i: European Business Review. - Bingley : Emerald Group Publishing Limited. - 0955-534X .- 1758-7107. ; 25:5, s. 411-428
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: This paper aims, by a direct comparison, to address the differences and similarities of the internationalization processes of multinational companies both from developed and emerging countries.Design/methodology/approach: This study employed qualitative approach, using an integrated model of internationalization process. Multiple case studies, with two companies with significant involvement in foreign markets and originating in countries with different levels of development, were carried out.Findings: The results reveal that the case companies show some differences with regards to their use of ownership advantages to facilitate their internationalization. On the other hand, learning and experience of internationalization, coupled with the use of networks, have been factors that have influenced the pace and the pattern of the case companies' internationalization. An integrated model, which includes variables related to networks and learning/experience, may contribute to the understanding of the case of multinational companies from emerging economies.Originality/value: Although the research field of emerging multinationals has been growing lately, very few attempts have been made in the sense of directly comparing the internationalization process of firms from both developed and emerging countries. The authors proposed an integrated analytical model that draws on insights from the eclectic paradigm and the Uppsala internationalization model. © Emerald Group Publishing Limited.
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| 8. |
- Amal, Mohamed, et al.
(författare)
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Strategies and determinants of Foreign Direct Investment (FDI) from developing countries : Case study of Latin America
- 2009
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Ingår i: Latin American Business Review. - Philadelphia, PA : Routledge. - 1097-8526. ; 10:2-3, s. 73-94
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of this study is to assess the importance of economic and institutional factors for outward Foreign Direct Investment (FDI) from Multinational Enterprises (MNEs) originating in the developing countries. The estimate drawn up through a panel data model for three countries in Latin America shows that these outflows are directly influenced by economic factors, such as gross-domestic product (GDP) growth and rising foreign exchange rates. Moreover, FDI is positively correlated with institutional variables such as globalization and education as well as with inward FDI stocks in their respective countries of origin. © Taylor & Francis Group, LLC.
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| 9. |
- Awuah, Gabriel, et al.
(författare)
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Impact of globalization : The ability of less developed countries' (LDCs') firms to cope with opportunities and challenges
- 2011
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Ingår i: European Business Review. - Bradford : Emerald Group Publishing Limited. - 0955-534X .- 1758-7107. ; 23:1, s. 120-132
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Tidskriftsartikel (refereegranskat)abstract
- Purpose – The purpose of this study is to contribute to the debate on the impact of globalization on the competitiveness of firms in least developed countries (LDCs). Two main research questions will be addressed. How does globalization affect the competitiveness of small to medium-sized enterprises (SMEs) in LDCs? How can SMEs handle opportunities and challenges emerging from globalization?Design/methodology/approach – The methodology for this study is a conceptual attempt to review the existing literature and make some propositions about how SMEs can handle the opportunities and challenges emerging from globalization.Findings – Building on a developed operational framework affecting the competitiveness of firms, some of the expected results are that firms' capabilities with regards to innovation, learning, and internationalization, which increase their competitiveness, are enhanced by institutional setups. Second, establishing relationships with governmental and non-governmental institutions is crucial in terms of accessing resources, innovating, and entering into foreign markets.Originality/value – The paper represents a contribution to the debate on the impact of globalization on the competitiveness of firms, particularly SMEs, in LDCs. Although globalization has brought considerable benefits to many actors worldwide, its impact on competitiveness of (SMEs) are controversial. We suggest that globalization's effects depend on the capability of firms to learning, to innovate, and also on the institutional setup in LDCs.
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| 10. |
- Awuah, Gabriel, et al.
(författare)
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The Internationalization of Multinational Companies (MNCs) : An intra-sector comparison among firms from developing and developed countries
- 2010
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Konferensbidrag (refereegranskat)abstract
- According to the international statistic data of the United Nations Conference of Trade and Development (Unctad, 2008), the majority of Multinational Companies (MNCs) are from developed countries. However, in the last decade the participation of MNCs from emerging economies in the international flows of Foreign Direct Investment (FDI) increased significantly, making them important global players. Although several scholars have addressed the internationalization process of emerging MNCs, no attempt has been made in the sense of directly comparing the internationalization process of firms from both developed and developing countries. To fill this gap, the aim of the present paper is to highlight the differences and similarities of the determinants and patterns of their internationalization. The integrated analytical model used in this study, which draws on insights from the Eclectic Paradigm and the Uppsala Internationalization approaches, has proved useful by helping to shed some light on the literature about MNCs’ internationalization process. The model in question has been structured in order to explore the differences and similarities of the internationalization processes of MNC from a developed and a developing country. This research uses a qualitative method with an exploratory nature, which allows deeper cross- cultural understanding. Multiple case studies of MNCs from countries with different levels of development (Brazil and Sweden) were carried out; this type of research allows addressing questions related to the determinants and patterns of internationalization. The results of the study show that there are strong evidences, which point out differences in term of ownership advantage development. However, the firms did not show substantial differences regarding internalization advantages. On the other hand, learning and experience of internationalization have been factors that have influenced the pattern and structure of the MNCs in both contexts. However, as the MNC from the developed country is more international and has longer experience, location decisions are no longer heavily influenced by these factors. The international network the MNC is part of and access to technology and knowledge partners are nowadays influencing the MNCs internationalization processes more. These findings are in line with earlier research that has pointed out that learning is most important in the early phases of MNCs international development while networks and location advantages are more important in later stages.
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