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Analysis of Monthly, Seasonal and Annual Air Temperature Variability and Trends in Taiz City - Republic of Yemen

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Journal of Environmental Protection 2010年第4期1卷 401-409页

作者： Mahyoub H. al Buhairi 不详

Climate change is one of the most important issues of today’s World. Climate scientists have concluded that the earth’s surface air temperature warmed by 0.6 ± 0.2℃ during the 20th century, accompanied by changes in the hydrologic cycle. Of all the climate elements, temperature plays a major role in detecting climate change brought about by urbanization and industrialization. this study focuses on the variability and trends of the mean annual, seasonal and monthly surface air temperature in Taiz city, Republic of Yemen, during the period 1979-2006. the results of the analysis of the whole period reveal a statistically significant increasing trend in practically all the months and seasons. A tendency has also been observed towards warmer years, with significantly warmer summer and spring periods and slightly warmer autumn and winter, an increase of 1.79℃ and 1.18℃ has been observed in the mean summer and mean winter temperature, respectively. Positive trends of about 1.5℃ in the annual mean temperature were found for the whole period. the air temperature time series are analyzed, so that the variability and trends can be described.

关键词： Air Temperature Climate Change Republic of Yemen Taiz City Mann–Kendall Test Trends

Edmund Becher Wilson＇s Early Contributions to the Chromosome theory of Heredity： A Case Study of Instrumentalism in Science

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Journal of Philosophy Study 2015年第9期5卷 431-443页

作者： Lilian al-Chueyr Pereira Martins University of Sao Paulo

the chromosome theory of inheritance was established during the three first decades of the 20th century. During the early stage of its substantiating, there were lots of puzzles and little evidence that could validate it. the cytological processes were obscure and several scientists maintained serious doubts concerning the existence of a connection between Mendel＇s principles and the behaviour of chromosomes during cell division. It was vital to associate an external, observable characteristic of the organism to a specific chromosome, and this was achieved when sex was connected to special chromosomes. At that time, however, some important scholars refused to accept or delayed acceptance of the conception that the hereditary factors （later called genes） were physical entities located along the chromosomes. Such was the case of thomas Morgan （1866-1945） and William Bateson （186 I- 1926）. their attitudes could be explained by considering the doubtful ground of the hypothesis at that time. It is more difficult, however, to understand the attitude of Edmund Beecher Wilson （1856-1939）. Being an expert in cytology he was acquainted with all the difficulties concerning the chromosome hypothesis. Nonetheless, from 1905 onward, he attributed little weight to the problems and dedicated a notable effort to obtaining evidence that could have grounded it. this paper analyses Wilson＇s attitude focusing on his studies from 1900 to 1915 and the scientific context of this period. this study led to the conclusion that Wilson＇s attitude could be explained in methodological terms by the adoption of an instrumentalist attitude, while Bateson and Morgan adopted a realistic perspective.

关键词： history of genetics philosophy of biology chromosome hypothesis/theory Wilson Edmund Beecher instrumentalism

Path Integral Approach to Faraday's Law of Induction

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Journal of Electromagnetic Analysis and Applications 2011年第6期3卷 184-186页

作者： Sami Mohammad al-Jaber An-Najah National University

We derive a general form of the induced electromotive force due to a time-varying magnetic field. It is shown that the integral form of Faraday's law of induction is more conveniently written in the covering space. thus the differential form is shown to relate the induced electric field in the nth winding number to the (n+1)th time-derivative of the magnetic field.

关键词： Faraday's Law of Induction Electromotive Force

CHARACTERISTICS OF CHANGE IN TEMPERATURE DURING thE PAST 50 YEARS IN JILIN PROVINCE OF CHINA

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Chinese Geographical Science 2002年第4期12卷 329-332页

作者： ZHAO Xin -yi,WAN Jun,WU Xiu -qin(Department of Urban and Environment al Sciences,Peking University,Beijing 100871,P.R.China) Department of Urban and Environmental Sciences Peking University Beijing P. R. China

Based on the monthly mean temperatu re,the changing processes and tendencies of temperature during1951-2000in Jilin Province,which i s in Northeast China,are analyzed.A nd the spatial characteristics of th e change are *** the past 50years the te mperature of Jilin Province was increasing just like the other areas in th e *** 1990,the increasing of temperature has been more obvious th an that in the previous *** the west to the east,the province has larger tem perature *** to Principal Component Analysis(PCA)of temperature field,Jilin Province is divided int o 3regions and the degree of becoming warmer is different from region to re *** the period of 1951to 2000,the annual temperature in Jilin Province has been rising,so has the temperature in winter and *** average temperature in t he 1990s was 0.5-2.0℃higher than that in the *** the west to the east,the increasing of temperature becam e smaller.

关键词： temperature change spatial characteristics jilin province

Mixed symmetry states and electromagnetic transition properties in the N=Z nucleus 28Si

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Mixed symmetry states and electromagnetic transition propert...

Carbon Sequestration Service of a Ramsar Site: A Conservation-Role Model for Defying Developmental Pressure in the Middle of a Rapidly Expanding City

第十三届全国核结构研讨会暨第九次全国“核结构与量子力学”专题讨论会

作者： al-Khudair Department of Physics Tsinghua University Department of Physics College of EducationBasrah UniversityBasrahIraq

the interacting boson model with isospin（IBM-3） has been used to study the mixed symmetry states and electromagnetic transition properties at low spin for *** theoretical calculations are in agreement with experimental *** interacting boson model（IBM） is one algebraic model describing the nucleus collective motion,which was introduced by Arima and *** the Bohr and Mottelson theory（BBM）,the nucleus is anentity with geometry shape and the nucleus collective motion is studied by using dynamic variables of the transformation *** IBM reveals the new dynamic symmetric characters and establishes the wave functions based on degrees of freedom of boson and group *** model is a very effective phenomenological model for describing low-lying collective motions of *** the original version（IBM-1）,only one kind of boson is considered,and it has been successful in describing various properties of medium and heavy even-even *** proton and the neutron in the heavy nuclei lie in different major shells and the bosons are further classified into proton-boson and neutron-boson in *** IBM-2,mixed symmetry in the proton and neutron degrees of freedom has been predicted,and discovered in electron-scattering *** lighter nuclei,the valence protons and valence neutrons are filling the same major shell and the isospin should be taken into account,so the IBM has been extended to the interacting boson model with isospin（IBM-3）.In the IBM-3,three types of bosons including proton-proton boson（s,d）,neutron-neutron boson（s,,d） and proton-neutron boson（s,d） the three s-boson and three d-boson form the isospin T=1 triplet.

关键词： IBM-3 isospin mixed symmetry states electromagnetic transitions

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Open Journal of Forestry 2021年第4期11卷 381-397页

作者： Abdullah Sulaiman al-Nadabi Hameed Sulaiman Biology Department College of Science Sultan Qaboos University Al-Khod Oman

Mangroves in coastal cities are under threat due to development pressures. However, mangrove ecosystems can serve as a potential carbon sink for mitigating the impacts of climate change. the main objective of this study was to estimate the carbon sequestration potential of mangroves in the al-Qurm natural reserve, Muscat, Oman. the reserve was classified into three distinct zones and was estimated through field measurement and remote sensing techniques. the study found that each zone sequesters varying levels of carbon. the highest mean carbon stock was measured in the landward zone (20.2 ± 0.3 kg∙C/m2), followed by the middle zone (8.7 ± 0.4 kg∙C/m2) and seaward zone (5.8 ± 0.8 kg∙C/m2), respectively. The carbon sequestration rate of the sediment range was between 5.0 g C/m2∙year - 12.5 g C/m2∙year. Normalized difference vegetation index (NDVI) derived from above-ground biomass showed a positive relationship (r = 0.73) with biomass measured in the field. However, the average above-ground carbon was underestimated (6.3 kg∙C/m2) th

关键词： Biomass Carbon Sequestration Mangroves Remote Sensing Cities

Water conservation in the Arab region: a must for survival

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Research in Cold and Arid Regions 2013年第1期5卷 157-164页

作者： Gamal M. Abdo Abdin M. A. Salih Abdulmohsen al-Sheikh Civil Engineering Department University of Khartoum Sudan alzamil Group Chair King Saud University Riyadh Saudi Arabia

the Arab region covers an area over 13 million square kilometers in size, with almost 90% of its area classified as arid or ex- tremely arid with very little precipitation, extremely high evaporation and almost no vegetation cover. the region is classified in many international reports as the poorest region in the world in the context of renewable water resources and critical water scarcity which hinders the socio-economfic development of many countries in this region. the rapidly increasing population has reduced the per capita share of renewable water to less than the poverty line of 1,000 m3/（capita＇a） and, in some Arab countries, to less than the extreme poverty line of 500 m3/（capita＇a）. this has led to over-exploitation of non-renewable groundwater and desalination of salty water in many countries with considerable costs and contamination of many renewable sources. Atmospheric processes re- sponsible for aridity in the Arab region are projected to intensify due to climate change, resulting in an alarming decrease in pre- cipitation and increase in evaporation rates. Many concerned entities in the region consider water security as a key element for food security and ultimately political stability. Hence, various efforts have been exerted to identify key problems and suggested solutions. the Arab Water Ministers Council of the Arab League, as well as Reports of the Arab Forum for the Environment and Development （AFED） and the recommendations of the 13th Regional Meeting of the Arab National Committees of the Interna- tional Hydrological Programme of UNESCO （niP）, have all made similar recommendations on the need to address the issues of water scarcity in the Arab region which will be further discussed in this paper. However, none of these reports focused on ＂Water Conservation＂ as an equally important action for coping with water scarcity in the region. there are many definitions for ＂Water Conservation＂ in the scientific literature, including huge water savings

关键词： arid zone water scarcity water security irrigation efficiency climate change water harvesting water reuse

Comparative Study of the Impact of Corundum Particle Contaminants Size on Wear and Fatigue Life of Grease Lubricated Ball Bearings

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Modern Mechanical Engineering 2013年第4期3卷 161-170页

作者： D. Koulocheris A. Stathis th. Costopoulos G. Gyparakis School of Mechanical Engineering National Technical University of Athens Athens Greece

Ball bearings’ rating life is reduced with the presence of hard particle contaminants in the lubricant. this life reduction is taken into account when calculating the modified rating life by using the contamination factor. the contamination factor is based on a general characterization of the lubrication conditions but the impact of contaminant’s variables such as size, hardness and concentration level is not determined in detail. In this work, greases contaminated with hard corundum (alumina, al2O3) particles of different sizes are tested aiming at finding a pattern in the relationship between particle sizes’ and wear’s progress. A laboratory rig is utilized for these tests and vibration analysis tools regarding bearings’ condition and estimated residual life are being assessed. After the tests, optical inspections using a stereoscope verify the vibration analyses results. the experimental results show that wear is progressing faster when smaller particles are used. the crystalline structure of the corundum and the different degree of brittleness of the contaminants seem to be the reasons for this behavior, whereas severe abrasion and deformation of the raceways have been detected.

关键词： Debris Grease Contaminants Hardness Wear Vibration

Effect of Peaches, Pears and Green Tea on Plasma Lipids Profile and Antioxidant Content in Rats Fed High Sucrose Diet

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Food and Nutrition Sciences 2015年第10期6卷 893-905页

作者： Nada A. al Zunaidy Noorah S. al-Sowayan Hassan M. Mousa Department of nutrition College of Design and Home Economic Qassim University Qassim Saudi Arabia Department of Biology Faculty of Science Buraidah Qassim University Qassim Saudi Arabia Department of Food Science and Human Nutrition College of Agriculture &Veterinary Medicine Qassim University Qassim Saudi Arabia

the beneficial effects of feeding syrup of peaches and pears (peel and pulp) & green tea on the restoration of the changes produced by feeding high sucrose diet on plasma lipid profile, plasma antioxidant activity, and antioxidant enzymes in red blood cells (RBC) hemolysate were studied. High sucrose diet induced hyperlipidemia as manifested by significant (P ≤ 0.05) increases in the levels of cholesterol, triglycerides (TG) and low density lipoproteins (LDL) in plasma from 103.33 ± 1.8, 61.17 ± 0.48 and 26.6 ± 5.01 mg/dl to 136.67 ± 2.2, 81.3 ± 1.5 and 64.6 ± 6.5 mg/dl respectively. the high density lipoproteins (HDL) level was not significantly affected. TG levels in heart muscles increased significantly P ≤ 0.05 from the level of 194.14 ± 4.35 μg/g in the negative control to 269.72 ± 5.39 μg/g. Administration of fruits syrup and green tea resulted in a significant variable reduction in the elevated levels of cholesterol, TG and LDL and TG in the heart. Administration of sucrose resulted also in elevation of Malondialdehyde (MDA) in plasma from 5.06 ± 0.18 in the negative control to 14.81 ± 0.48 μmol/L in the positive control. this was also accompanied by reduction in the activities of supper oxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT) and a decrease in the concentration of reduced glutathione (GSH) in plasma, indicating lipid peroxidation. the activities of SOD, GSH-Px, CAT in the negative control were 8.96 ± 0.19, 315.67 ± 5.86, 209 ± 2.18 U/gHb respectively and were reduced significantly in the positive control to 4.7 ± 0.2, 273.83 ± 7.85, 207 ± 2.53 U/g Hb. there was a significant decrease in the level of total antioxidant status (TAS) in plasma from 1.45 ± 0.09 to 0.88 ± 0.09 nmol/L. However, no statistically significant changes were noticed in the concentrations of plasma total proteins and albumin. Intake of syrup of peaches and pears (peel and pulp) & green tea increased the level of TAS and GSH and decreased the level of LDL. th

关键词： Sucrose Lipid Profile Lipid Peroxidation Green Tea Fruits