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Asymmetric Reformatsky Reaction Induced by Dipeptides

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Chinese Chemical Letters 2000年第8期11卷 659-662页

作者： Wang, ZY Shen, J Jiang, cs You, TP Univ Sci & Technol China Dept Chem Hefei 230026 Peoples R China

For the first time, synthetic dipeptides were applied to the catalysis of asymmetric Reformatsky reaction. Review in this domain & factors influencing enantioselectivity were discussed.

关键词： dipeptide derivative chiral ligands catalysis asymmetric Reformatsky reaction

DETERMINATION　OF　TRACEFLUORIDE　AND　MOLYBDENUM　IN　SERUM　SAMPLE　BY　ELECTROCHEMICAL　ANALYSIS

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Chinese Chemical Letters 1996年第2期7卷 161-164页

作者： Wang, LZ Zhang, XL Yu, Y Ma, cs SHANDONG UNIV DEPT CHEMJINAN 250100PEOPLES R CHINA

In thia paper, the determination of both fluoride and bolybdenum can be carried out in the same serum sample as follows: the content of fluoride is determined by direct potentiometry in the solution containing (CH2)6N4 and HNO3(pH= 5. 4) while that of molybdenum is determined by adsorptive vol tammetry after the above-mentioned solution has been nitrified with mixed acid containing HNO3 and HC104.

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Characterization and Utilization of Starches Extracted from Florencia and Waxy Maize Hybrids for Tablet Formulation: Compaction Behaviour and Tablet Properties

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American Journal of Plant Sciences 2014年第6期5卷 787-798页

作者： Anikó Szepes Piroska Szabó-Révész János Bajdik Péter Kása Jr. Miklós Neményi Roland Pap attila József kovács Klára Pintye-Hódi Martin Luther University Halle-Wittenberg Center for Engineering Thermal Process Technology Halle (Saale) Germany Department of Pharmaceutical Technology University of Szeged Szeged Hungary Faculty for Agricultural and Food Sciences Institut of Biosystems Engineering University of West Hungary Mosonmagyaróvár Hungary

The aim of this work is to analyze the particle characteristics, such as shape, roundness and size, of starches extracted from Florencia and waxy maize hybrids. The micromeritics and structural properties of the samples were examined. The evaluation of flow properties, densification and compression behaviour of the powders was carried out. Physical parameters and swelling characteristics of tablets containing Florencia and waxy maize starch were also studied. Starch samples were compared with respect to their applicability as excipients in tablet formulation. The samples exhibited identical structure and similar particle characteristics. Maize starch extracted from the Florencia dent hybrid showed better flowability and compressibility in tableting experiments, which resulted in better mechanical tablet properties. With regard to utilization as a disintegrant, Florencia starch indicated rapid and intensive swelling and proved to act more effectively in the swelling process than waxy maize starch.

关键词： Maize Starch Micromeritics X-Ray Diffraction Compression Behaviour Tablets

Effects of carbon content and solidification rate on thermal conductivity of grey cast iron

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China Foundry 2007年第3期4卷 210-214页

作者： Daniel Holmgren attila Diószegi Ingvar L.Svensson Jnkping University Dept. of Mechanical Engineering/Component TechnologyJnkpingSE-551 11Sweden

The thermal conductivity or diffusivity of pearlitic grey irons with various carbon contents is investigated by the laser flash method. The materials are cast in controlled thermal environments and produced in three dissimilar cooling rates. The cooling rate together with the carbon content largely influence the thermal conductivity of grey iron. Linear relationships exist between the thermal conductivity and the carbon content,the carbon equivalent and the fraction of former primary solidified austenite transformed into pearlite. The work shows that optimal thermal transport properties are obtained at medium cooling rates. Equations describing the thermal conductivity of pearlite,solidified as pre-eutectic austenite,and the eutectic of grey iron are derived. The thermal conductivity of pearlitic grey iron is modeled at both room temperature and elevated temperature with good accuracy.

关键词： grey iron thermal conductivity thermal diffusivity carbon content carbon equivalent colour etching graphite morphology eutectic cell size primary austenite cooling rate

How to explore a new environment:exploratory tactics of the black rat(Rattus rattus)

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Current Zoology 2024年第3期70卷 371-382页

作者： Iveta Štolhoferová Veronika Rudolfová Hana Skalíková Barbora Vobrubová Daniel Frynta Department of Zoology Faculty of ScienceCharles UniversityViničná712843 Prague 2Czechia

The black rat(Rattus rattus)is a unique model for studying exploratory tactics due to its enormous colonizing *** behavioral variability and consistent interindividual differences might help populations inhabit new environments and persist there even under intense ***,the affnity of the black rat for climbing might be another advantage,widening their potential *** this study,we describe the exploratory tactics of the black rats when introduced to a novel *** the frst experiment,we tested 12 rats and calculated repeatability of their behaviors across 12 sessions of an enriched open-feld *** concluded that climbing is a highly repeatable behavior that serves as an important source of interindividual *** the second experiment,we tested 24 black rats in a unique L-shaped *** rat was tested *** found that the majority of rats distributed their activity evenly,exploring each part of the apparatus for a similar amount of time,thus maximizing their chances of fnding ***,these“even”explorers still greatly differed in their level of activity,orderliness and affnity for climbing,generating large *** contrast,the minority of rats concentrated their activity only on a section of the new environment and were therefore characterized as selective ***,we concluded that a combination of such exploratory tactics as well as a bias for even explorers enables black rats to quickly colonize new environments and persist there even under unfavorable conditions.

关键词： 3D behavior climbing repeatability strategy.

Role of Fresh Cadaver Practice and Jesus Prayers on Daily Base in Innovations of a Difficult Neurosurgical Operation (Craniopagus Separation)

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Open Journal of Modern Neurosurgery 2023年第4期13卷 189-201页

作者： András csókay István Hudák István Valálik attila Jósvai Bence Trencsényi Előd Égető Bertalan Tóth Bernadett csókay Gergely csókay Department of Neurosurgery North-Pest Central Hospital Budapest Hungary Department of Pediatric Surgery and Traumatology St. John’s Hospital Budapest Hungary Department of Neurosurgery St. John’s Hospital Budapest Hungary Department of Maxillo-Facial Surgery Semmelweis University Clinic of Maxillo-Facial Surgery Budapest Hungary

Purpose: Challenging cases in neurosurgery require experience, which is gained by operating on a number of similarly difficult cases. However, even in large population centers, there are extremely rare cases, such as craniopagus twins. In these instances, other case-specific solutions are required which were improved in the course of fresh cadaver practice on daily base. Methods: During a 20-month preparation period by fresh cadavers the surgical strategy was developed step by step, comprising five neurosurgical ideas, facilitated by deep Jesus prayers as a spiritual source. Possible causes of postoperative complications that occured on 33d postoperative day were also analyzed. Results: During surgery, these nuances proved to be useful, which is also reflected by the postoperative clinical results. One of the twins advanced to a GOS score of 5three months after the surgery. The other twin, despite nonsurgical septic complications, continued to progress well, but on postoperative day 33 for seemingly unknown reasons, she suffered a severe cerebral hemorrhage, which significantly delayed her rehabilitation. A thorough revision of the whole process much later revealed a pitfall that could have a role in this complication. Conclusions: The challenging neurosurgical separation of the craniopagus twins was carried out successfully with the help of five novel neurosurgical refinements, which were found during 300 fresh cadaver practices. Mistakes can serve as a lesson. We hope that the procedures developed and the knowledge gained can be applied in the future.

关键词： Craniopagus Conjoined Twins Fresh Cadaver Practice

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人口进程与青年失业的相互关系

中国青年研究 2009年第5期 11-13,74页

作者： kovācs Lāszló(柯瓦奇·拉斯洛)[匈牙利] 杨巧(翻译) 卢德平(校对) 匈牙利科学院不详

青年失业与生育率有关,与人口迁移也有联系。低生育水平带来的人口失衡,以及平均预期寿命的波动,会导致经济危机,并危及到欧洲相对于世界其他地区的竞争力。养老金和社会保障体系成本的日益上升,会导致退休年龄的推迟。养老金的推后,会... 详细信息

青年失业与生育率有关,与人口迁移也有联系。低生育水平带来的人口失衡,以及平均预期寿命的波动,会导致经济危机,并危及到欧洲相对于世界其他地区的竞争力。养老金和社会保障体系成本的日益上升,会导致退休年龄的推迟。养老金的推后,会造成领取者和青年人的焦虑,导致失业率的上升。减少青年失业的政策,可以调节这一现象带来的全球性消极影响,但是人口问题所带来的后果却是多样和错综复杂的。

关键词：生育率平均预期寿命人口迁移青年失业就业政策

Endometriosis and ovarian cancer

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World Journal of Clinical Oncology 2014年第5期5卷 800-805页

作者： Milena Králí?ková Vaclav Vetvicka Department of Histology and Embryology Faculty of Medicine Charles University Plzen CZ-301 00 Czech Republic Department of Obstetrics and Gynecology University Hospital Faculty of Medicine Charles University Plzen CZ-301 66 Czech Republic Biomedical Centre Faculty of Medicine in Plzen Charles University Plzen CZ-301 66 Czech Republic Department of Pathology University of Louisville Louisville KY 40202 United States

Endometriosis is the leading cause of morbidity among premenopausal women and the complex pathogenesis of this disease remains controversial despite extensive research. This disease represents one of the most common gynecological problems. It is generally believed that this disease is due primarily to retrograde menstruation or transplantation of shed endometrium. Based on overwhelming data, ovarian endometrioma is considered a neoplastic process, since most endometriosis-associated ovarian carcinoma occur in the presence of atypical ovarian endometriosis. A study comparing patients with typical epithelial ovarian cancer with endometriosis-associated ovarian cancer demonstrated that the patients with the latter disease strongly differ in both biological and histological characteristics. The prevelance of this disease is not completely established, but approximately 15 percent of women suffer from this disease. In addition, we know about the possible links between endometriosis and cancer for almost 100 years. Despite clear evidence revealing that endometriosis increases ovariancancer risks, it is possible that it may not affect disease progression after the appearance of ovarian cancer. However, despite clear evidence revealing that endometriosis increases ovarian cancer risk, our knowledge of the risk factors is far from established. In our review, we focused on the most recent approaches including possible biomarkers and genetic approaches.

关键词： Endometriosis Ovarian cancer Biomarkers Cancer Histology

Handmade cloning:recent advances,potential and pitfalls

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Journal of Animal Science and Biotechnology 2015年第4期6卷 378-387页

作者： Geetika Verma JS Arora RS Sethi cs Mukhopadhyay Ramneek Verma School of Animal Biotechnology Post Graduate Institute of Veterinary Education and ResearchGuru Angad Dev Veterinary and Animal Sciences University

Handmade cloning （HMC） is the most awaited, simple and micromanipulator-ffee version of somatic cell nuclear transfer （SCNT）. The requirement of expensive micromanipulators and skilled expertise is eliminated in this technique, proving it as a major revolution in the field of embryology. During the past years, many modifications have been incorporated in this technique to boost its efficiency. This alternative approach to micromanipulator based traditional cloning O-C） works wonder in generating comparable or even higher birth rates in addition to declining costs drastically and enabling cryopreservation. This technique is not only applicable to intraspecies nuclear transfer but also to interspecies nuclear transfer （iSCNT） thus permitting conservation of endangered species. It also offers unique possibilities for automation of SCNT which aims at production of transgenic animals that can cure certain human diseases by producing therapeutics hence, providing a healthier future for the wellbeing of humans. The present review aims at highlighting certain aspects of HMC including recent advancements in procedure and factors involved in elevating its efficiency besides covering the potentials and pitfalls of this technique

关键词： Handmade cloning Micromanipulator Somatic cell nuclear transfer Transgenic Zona free cloning