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some Dielectric Properties of some Resin Varnishes

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Journal of Materials science & Technology 1995年第2期11卷 119-121页

作者： s.A.El-Henawii(Faculty of science, Helwan University, Cairo, Egypt) Heiwan Univ Cairo Egypt

The dielectric constant, the dielectric loss and the power factor of three types of resins namely polyesteramide, alkyd polyesteramide and alkyd resins were measured with in the frequency range of 105 to 107 Hz and the temperature range of 20 to 50℃. The activation energy of dielectric relaxation and the entropy changes were also calculated using the usual rate equation. The results obtained are recorded and discussed.

关键词： some Dielectric Properties of some Resin Varnishes RT

Completing Einstein’s spacetime

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Journal of Modern Physics 2016年第15期7卷 1972-1994页

作者： M. s. El Naschie Department of Physics Faculty of Science Alexandria University Alexandria Egypt

The four-dimensional character of Einstein’s spacetime is generally accepted in mainstream physics as beyond reasonable doubt correct. However the real problem is when we require scale invariance and that this spacetime be four-dimensional on all scales. It is true that on our classical scale, the 4D decouples into 3D plus one time dimension and that on very large scale only the curvature of spacetime becomes noticeable. However the critical problem is that such spacetime must remain 4D no matter how small the scale we are probing is. This is something of crucial importance for quantum physics. The present work addresses this basic, natural and logical requirement and shows how many contradictory results and shortcomings of relativity and quantum gravity could be eliminated when we “complete” Einstein’s spacetime in such a geometrical gauge invariant way. Concurrently the work serves also as a review of the vast Literature on E-Infinity theory used here.

关键词： E-Infinity Cantorian spacetime self-similarity M-Theory Kaluza-Klein space Fuzzy Kähler Manifolds Continued Fraction Isomorphic Length Geometrical Gauge Invariance

summary evidence on the effects of varicocele treatment to improve natural fertility in subfertile men

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Asian Journal of Andrology 2016年第2期18卷 239-245,J0005页

作者： Bruno C Tiseo sandro C Esteves Marcello s Cocuzza Department of Urology University of Sao Paulo Av. Dr. Eneas de Carvalho Aguiar 255 7 andar - Sala 710F Sao Paulo 05403-000 Brazil ANDROFERT Center for Male Reproduction Av. Dr. Heitor Penteado 1464 Campinas Sao Paulo 13075-460 Brazil.

The objective of this review was to summarize the evidence concerning the benefit of varicocele treatment to improve natural fertility in subfertile males. We also analyzed the effect of varicocele treatment on conventional semen parameters and sperm functional tests. An electronic search to collect the data was performed using the PubMed/MEDLINE databases until July 2015. Data pooled from a variety of study designs indicate that varicocelectomy improves semen parameters in the majority of the treated men with clinical varicocele and abnormal semen parameters regardless of the chosen surgical method. surgical varicocele repair was beneficial not only for alleviating oxidative stress-associated infertility but also to improve sperm nuclear DNA integrity. However, given the low magnitude of the effect size in sperm DNA integrity, further research is needed to elucidate its clinical significance. Conflicting results on the effect of varicocele treatment on natural fertility seem to be due to heterogeneous study designs and, more importantly, patient selection criteria. When these issues are controlled, current evidence indicates that treatment of subclinical varicocele is not warranted, as it does not seem to improve fertility. On the contrary, fair evidence indicates that varicocele treatment should be offered to infertile patients with palpable varicocele and abnormal semen parameters. This evidence supports the current guidelines issued by the American Urological Association and European Association of Urology, which state that varicocele treatment should be offered to male partners of infertile couples presenting for evaluation with clinical varicocele and semen parameters alterations.

关键词： male infertility review treatment outcome varicocele varicocelectomy

Electrochemical process of titanium extraction

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中国有色金属学会会刊：英文版 2007年第2期17卷 429-433页

作者： CH. RVs. NAGEsH C. s. RAMACHANDRAN Defence Metallurgical Research Laboratory HyderabadA.P. India-500058

A wide variety of processes are being pursued by researchers for cost effective extraction of titanium metal. Electrochemical processes are promising due to simplicity and being less capital intensive. some of the promising electrochemical processes of titanium extraction were reviewed and the results of laboratory scale experiments on electrochemical reduction of TiO2 granules were brought out. some of the kinetic parameters of the reduction process were discussed while presenting the quality improvements achieved in the experimentation.

关键词：钛萃取电化学还原过程动力学参数

Phytotoxicity of cadmium on protein, proline and antioxidant enzyme activities in growing Arachis hypogaea L. seedlings

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Journal of Environmental sciences 2008年第2期20卷 199-206页

作者： N Dinakar P C Nagajyothi s suresh Y Udaykiran T Damodharam Department of Environmental sciences Sri Venkateswara UniversityTirupatiAndhra Pradesh-517 502India.

Phytotoxicity of cadmium on growing Arachis hypogaea L. seedlings was studied. seeds were exposed to 25, 50, and 100 μmol/L CdCl2 concentrations, for a period of 10, 15, 20 and 25 d. The extent of damage to chlorophyll, protein, proline, nitrate and nitrite reductase, antioxidant enzyme activity in leaves and roots were evaluated after 10 d of cadmium stress. The higher concentration of cadmium （100 μmol/L） resulted （leaves and roots） total chlorophyll 91.01%, protein 79.51%, 83.61%, nitrate reductase 79.39%, 80.72% and nitrite reductase 77.07%, 75.88% activity decreased with increase in cadmium concentrations and exposure periods. Cadmium caused significant changes in the activity of antioxidative enzymes. Contrastingly Cd treated plant tissues showed an increase in proline 159.87%, 239.6%, gluthion reductase （GR） 337.72%, 306.14%, superoxide disumutase （sOD） 688.56%, 381.72%, ascorbate peroxidase （APX） 226.47%, 252.14%, peroxidase （POD） 72.19%, 60.29% and catalase （CAT） 228.96%, 214.74% as compared to control. Cadmium stress caused a significant increase in the rate of sOD activity in leaves and roots of plant species. Results show the crop A. hypogaea is highly sensitive even at very low cadmium concentrations.

关键词： toxicological effects cadmium protein proline antioxidant enzymes

The whole day matters: Understanding 24-hour movement guideline adherence and relationships with health indicators across the lifespan

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Journal of sport and Health science 2020年第6期9卷 493-510页

作者： scott Rollo Olga Antsygina Mark s.Tremblay Healthy Active Living and Obesity Research Group Children’s Hospital of Eastern Ontario Research InstituteOttawaONK1H 8L1Canada Department of Pediatrics Faculty of MedicineUniversity of OttawaOttawaONK1H 8M5Canada Department of Health sciences Carleton UniversityOttawaONK1S 5B6Canada

Background:New research suggests that the composition(mix)of movement behaviors within a 24-h period may have important implications for health across the *** with this integrated movement behavior paradigm,a number of countries across the world have developed and released 24-h movement guidelines for specific age *** purpose of this systematic review was to examine the associations between the 24-h time-use composition of movement behaviors,or adherence to 24-h movement guidelines,and multiple health indicators across the ***:Five online databases(PsycINFO,PubMed,sPORTDiscus,Web of science,and Ovid MEDLINE)were searched for relevant peer-reviewed studies published between January 2015 and January 2020 that met the a priori inclusion criteria,with no study design *** methodological quality of research evidence for each individual study and for each health indicator was assessed by using a modified version of the Downs and Black ***:A total of 51 studies from 20 different countries met the inclusion criteria.A total of 31 studies examined adherence(meeting *** meeting)to 24-h movement guidelines,and 20 studies used compositional analyses to explore the 24-h time-use composition of movement *** indicated that meeting the 24-h movement guidelines were(1)not associated with adiposity among toddlers,(2)favorably associated with health-related quality of life,social-cognitive development,and behavioral and emotional problems among preschoolers,(3)favorably associated with global cognition,health-related quality of life,and healthy dietary patterns in children,and(4)favorably associated with adiposity,fitness,and cardiometabolic,mental,social,and emotional health among children and *** associations were also found between the composition of 24-h movement behaviors and indicators of(1)adiposity and bone and skeletal health among preschoolers,(2)health-related quality of life among child

关键词： Compositional analysis Movement behaviors Physical activity sedentary behavior sleep

CuPc based organic-inorganic hetero-junction with Au electrodes

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Journal of semiconductors 2010年第7期31卷 22-25页

作者： Zubair Ahmad Muhammad H.sayyad Kh.s.Karimov Ghulam Ishaq Khan Institute of Engineering sciences and Technology TopiNWFP23460Pakistan Department of Mechanical Engineering 20 Symond Street AucklandUniversity of AucklandNew Zealand

A hetero-junction of n-silicon（n-si） and copper phthalocyanine（CuPc） has been *** current -voltage characteristics were investigated to explain the rectification and conduction *** effect of temperature and humidity on the electrical properties of n-si/CuPc hetero-junction has also been *** characteristics of the junction have been observed to be temperature and humidity dependent,so it is suggested that this junction can be used as a temperature and humidity sensor.

关键词： inorganic-organic hetero-junction n-si CuPc

Return to sport after lower limb arthroplasty-why not for all?

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World Journal of Orthopedics 2019年第2期10卷 90-100页

作者： shivan s Jassim Jenni Tahmassebi Fares s Haddad Angus Robertson Trauma and Orthopaedics Royal London Hospital Trauma and Orthopaedics University College London Hospital Trauma and Orthopaedics Cardiff and Vale NHS Trust

BACKGROUND Total hip and knee replacements are being performed in increasing numbers in progressively younger patients with higher activity demands. Many such patients have expectations of returning to athletic activity post-operatively yet are not always able to do so and the reasons behind this have not been extensively examined. We hypothesise that any reasons for a failure to return to athletic activity post-operatively are *** To quantify the return to athletic activity following lower limb joint arthroplasty and understand qualitative reasons for altered activity *** A single centre, single surgeon retrospective questionnaire for hip and knee arthroplasty patients under age 60 years, minimum two years post-surgery with exclusion criteria of multiple degenerative joint involvement and multiple medical co-morbidities. Outcomes were validated joint-specific(Oxford hip and knee) and lifestyle questionnaires [short form 12(sF-12) and University of California, Los Angeles(UCLA)] and an activity questionnaire assessing ability participation in athletic activity post-operatively. statistical analysis was performed on the validated outcome data, including comparison between hip and knee replacements. Frequency tables were produced to quantify the different athletic activities participated in by *** Responses were received from 64 patients(80% response rate). There was a statistically significant improvement in Oxford hip and knee scores following surgery. sF-12 scores also improved for all patients, but no statistically significant difference was seen between joints(P = 0.88). Mean UCLA scores pre-operatively were 7.67 and at two years post-operatively were 7.69, with no statistically significant change(P = 0.91). All patients reported high satisfaction and improved ability to perform athletic activity at a higher frequency compared to pre-operatively. The most common reasons for changing activity participation were not wa

关键词： Joint replacement Athletic activity sport Outcomes

Comparing children＇s Homo sapiens and chimpanzees＇ Pan troglodytes quantity judgments of sequentially presented sets of items

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Current Zoology 2011年第4期57卷 419-420,421-428页

作者： Michael J. BERAN Julie s. JOHNsON-PYNN christopher READY Language Research Center Georgia State University Atlanta GA 30302 USA Department of Psychology Berry College Mount Berry GA 30149 USA

We presented a quantity judgment task that involved comparing two sequentially presented sets of items to preschoolers and chimpanzees using nearly identical procedures that excluded verbal instructions to children. Trial difficulty in this task reflected the ratio difference between sets of discrete items where larger ratios （e.g., 0.80 as from comparing 4 to 5） were more difficult than smaller ones （e.g., 0.50 as from comparing 4 to 8）. Children also completed verbal-based tasks probing the relationskip between counting proficiency and performance on the quantity judgment task of sequentially presented identical sized items. Both species＇ performance was best when ratios between comparison sets were small regardless of set size in all types of tasks. Generally, chimpanzees and older children performed better than younger children except at larger ratios. Children＇s counting proficiency was not related to success in choosing the larger of two quantities of identical-sized items. These results indicate that chimpanzees and children share an approximate number sense that is reflected through analog magnitude estimation when comparing quantities [Current Zoology 57 （4）： 419-428, 2011].

关键词： Numerical cognition Quantity judgments Children Chimpanzees Pan troglodytes