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Journal of High Energy Physics, Gravitation and Cosmology 2022年第1期8卷 85-96页

作者： Gabriela Coutinho de Carvalho Maria emília Xavier Guimarães Pablo Oliveira Mesquita Joaquim Lopes neto Universidade Estadual do Rio de Janeiro Faculdade de Tecnologia Resende Brazil Instituto de Física Universidade Federal Fluminense Av. Litoranea S/N Niterói Brazil Instituto de Fsica Universidade Federal do Rio de Janeiro—UFRJ Av. Athos da Silveira Ramos Cidade Universitária Rio de Janeiro Brazil

The formation and evolution of cosmic string wakes in the framework of a f(R) theory of gravity are investigated in this work. We consider a simple model in which baryonic matter flows past a cosmic string. We treat this problem in the Zel’dovich approximation. We compare our results with previous results obtained in the context of General Relativity and Scalar-Theories of Gravity.

关键词： Topological Defects Alternative Theories of Gravity Structure Formation in the Universe

Periodontal Diseases in Pregnant Women in Prenatal Consultation

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Open Journal of Stomatology 2021年第9期11卷 349-359页

作者： Ekofo Edize nyimi Bushabu Fidele Mbungu Mwimba Mantshumba Milolo Augustin em Kalala Kazadi Sekele Isourady Bourley Department of Dental Medicine Periodontology Unit Faculty of Medicine Kinshasa University Kinshasa Democratic Republic of Congo Department of Dental Medicine Oral and Maxillofacial Surgery Service Faculty of Medicine Kinshasa University Kinshasa Democratic Republic of Congo national Center Laboratory of Oral Biomedicine Ministry of Research Innovation and Technology Kinshasa Democratic Republic of Congo Department of Gynecology Faculty of Medicine University of Kinshasa Kinshasa Democratic Republic of Congo Department of Dental Medicine Prosthodontics and Orthodontics Service Faculty of Medicine University of Kinshasa Kinshasa Democratic Republic of Congo

Background: The relationship between pregnancy and periodontal health had well documented in the literature. Of many studies of periodontal diseases in the Democratic Republic of Congo, no study had evaluated these di... 详细信息

ng>Background:ng> The relationship between pregnancy and periodontal health had well documented in the literature. Of many studies of periodontal diseases in the Democratic Republic of Congo, no study had evaluated these diseases in pregnant women during Prenatal Consultation (PC). This study aimed to describe the occurrence and clinical profile of periodontal diseases in pregnant women admitted to the PC at the General Military Hospital of BOBILA. ng>Materials and Methods:ng> It is a cross-sectional and analytical study of pregnant women admitted to the PC from August to December 31, 2018, at the General Reference Military Hospital of BOBILA/Kinshasa City. The data were collected through a survey combined with the stomatological interview. Sociodemographic data, clinical and periodontal indices included Oral Hygiene Index Simplified (OHI-S), Bleeding on Probing (BOP), and Periodontal Disease Index (PDI) were assessed. The statistical analyses were carried out using the SPSS version 20.0 software. The Chi-square tests, Student t-test were used to determine differences in the distribution of variables, and the odd Ratio with a confidence interval (IC) at 95% was used to estimate the degree of association. The results were significant at p ng>Results:ng> Of the 105 pregnant women received at the PC, 83 were included in this study. The age group between 20 - 29 was the most represented, with a predominance of stay-at-home mothers (75.9%) and married cases (73.4%), they had an average economic status (56.6%) and a secondary education level (63.8%). Gingival bleeding (44.6%) was the main complaint of the pregnant. Gestational age was a significant factor associated with gum bleeding (p nant had poor oral hygiene, localized gravidities (69.6%) during the third semester. ng>Conclusion:ng> A significant proportion of women had experienced periodontal diseases during the pregnancy period, mostly in

关键词： Periodontal Diseases Clinical Profile Pregnant Women

A nEW MOMEnT METHOD FOR THE FAST AnD ACCURATE AnALYSIS OF nORMAL MODE HELICAL AnTEnnAS

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Journal of Electronics(China) 2001年第4期18卷 355-358页

作者： Ji Yicai Sun Baohua Liu Qizhong (Institute of Antennas and em Scattering, Xidian University, Xi’an 710071) Institute of Antennas and IM Scattering Xidian University Xi'an 710071

In this letter, a new moment method using helical segments is presented to model normal Mode Helical Antenna (nMHA). Using this method, the nMHA can be modeled by a few segments. The current distributions and radiation patterns of some nMHAs are calculated.A comparison is made between results obtained using this helical segment algorithm and a linear segment algorithm, and the results of the two algorithms agree fairly well. When calculating the impedance matrix [Z], all the elements of the matrix can be obtained by only calculating a few elements with the application of the symmetric and periodic characteristics of the ***, the CPU time and the memory storage are significantly reduced, with the accuracy and speed enhanced.

关键词： Moment method Helical segment normal Mode Helical Antenna (nMHA)

Teleportation of Entangled States through Divorce of Entangled Pair Mediated by a Weak Coherent Field in a High-Q Cavity

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Chinese Physics Letters 2008年第7期25卷 2488-2491页

作者： W. B. Cardoso n. G. de Almeida Instituto de Ffsica Universidade Federal de Goiaes 74.001-970 Goiaenia (GO) Brazil nucleo de Pesquisas em Fisica Universidade Catoelica de Goids 74.605-080 Goiania (GO) Brazil

We propose a scheme to partially teleport an unknown entangled atomic state. A high-Q cavity, supporting one mode of a weak coherent state, is needed to accomplish this process. By partial teleportation we mean that teleportation will occur by changing one of the partners of the entangled state to be teleported. The entangled state to be teleported is composed by one pair of particles, we called this surprising characteristic of maintaining the entanglement, even when one of the particle of the entangled pair being teleported is changed, of divorce of entangled states.

关键词： UnKnOWn ATOMIC STATE DETERMInISTIC QUAnTUM TELEPORTATIOn PODOLSKY-ROSEn CHAnnELS SCHemE SUPERPOSITIOn OPERATIOnS LIGHT

HYBRID MM/MoL APPROACH FOR AnALYZIng A COAXIAL FED MOnOPOLE AnTEnnA

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Journal of Electronics(China) 2002年第1期19卷 84-88页

作者： Sun Baohua Ji Yicai Liu Qizhong (institute of Antennas and em Scattering, Xidian University, Xi’an 710071) Institute of Antennas and em Scattering Xidian University Xi'an 710071

A new hybrid technique is presented, which combines the Mode Matching (MM) method with the Method of Lines (MoL) to analyze a coaxial fed monopole antenna. The monopole antenna is dealt with using the MoL, while the MM method is used to analyze the coaxial feed system. Then, the two sub-problems are combined by enforcing point matching at the common regional interfaces. The input impedance is computed and compared with the measured data reported in literature, and the excellent agreement is observed.

关键词： Monopole antenna MoL MM method

AnALYSIS OF THE SCATTERIng OF RIvET On AIRCRAFT

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Journal of Electronics(China) 2002年第4期19卷 434-437页

作者： Guo Jingli Ji Yicai Liu Qizhong (institute of Antenna & em Scattering, Xidian University, Xi’an 710071) Institute of Antenna & em Scattering Xidian University Xi'an 710071

This letter investigates the scattering characteristic of the rivets on aircraft. The Electric Field Integral Equation (EFIE) is used with the moment method to calculate the current distribution on the surface of the rivet. With the application of Gaussian integral corresponding triangular cell, the time to fill the Z matrix is greatly reduced. Finally, the RCS of a type of rivet on aircraft is analyzed.

关键词： Moment method Radar Cross Section(RCS) Aircraft Rivet

Effects of human umbilical cord serum on proliferation and insulin content of human fetal islet-like cell clusters

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Hepatobiliary & Pancreatic Diseases International 2004年第1期3卷 144-148页

作者： Dong Xia, Hong-Yuan He, Zheng-Ming Lei, Pei-Ming Zhang and Yong Guo Luzhou, China Department of General Surgery, West China Hospital , and Department of Surgery, Fifth Hospital of Sichuan Province , Chengdu 610041, China Department of Histology and em- bryology , and Hepatobiliary and Pancreatic Laboratory , Luzhou Medical College, Luzhou 646000, China Department of General Surgery West China Hospital Chengdu 610041 China. juliahhy@***

BACKGROUnD: Type 1 diabets is an autoimmune disease caused by the destruction of pancreatic β-cell with an in- creased incidence worldwide in the closing decades of the 20th century. This study was to investigate the effects of human umbilical cord serum (UCS) on the proliferation and function of human fetal islet-like cell clusters (ICCs) in vitro. METHODS: Eight fresh pancreatic glands obtained after in- duction of labor with water bag were mildly exposed to col- lagenase v, and the digested cells were cultured in a RPMI- 1640 medium plus 10% pooled UCS or fetal calf serum (FCS) to permit cells attachment and outgrowth of ICCs. RESULTS: In 8 consecutively explanted glands, develop- ment and proliferation of ICCs were observed. In the pre- sence of FCS, the outgrowth of ICC took place on the top of a flbroblast monocellular layer. UCS affected less growth of fibroblasts and increased the formation of ICCs about four-fold compared with explants from the same glands maintained in FCS. In both UCS and FCS, the insulin con- tent of the medium was variable to a certain extent and progressively declined from day 2 to day 6. Dithizone- stained ICCs in UCS suggested that most cell clusters were islet cells ( β-cells), and the purity of islets was estimated 80%-90%. The ultrastructure of the cultured cells showed a large number of granule-containing cells, most of which were identified as β-cells. COnCLUSIOn: We conclude that in comparison with ex- plants with FCS, the yield of ICCs and purification of islet cells are markedly increased by UCS and may facilitate the proliferation of pancreatic β-cells intended for islet trans- plantation.

关键词： islet cell culture islet-like cells clusters umbilical cord serum fetal calf serum

AnALYSIS OF MOnOPOLE AnTEnnA On CIRCULAR DISC BY MODE MATCHIng

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Journal of Electronics(China) 2001年第2期18卷 185-187页

作者： Sun Baohua Zhang Pushun Liu Qizhong (Institute of Antennas and em Scattering, Xidian University, Xi’an 710071) Institute of Antennas and em Scattering Xidian UniversityXi'an 710071

Mode matching is used for the analysis of monopole antenna on circular disc, which is achieved by developing a novel model consisting of two artificial ground planes above and bellow the monopole antenna. Using this model, the input impedance is computed and compared with measured data reported in literatures, and excellent agreement is observed.

关键词： Monopole antenna Mode matching Circular disc

nest site selection and reproductive parameters of the threatened Atlantic Royal Flycatcher(Onychorhynchus swainsoni)and their significance for conservation

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Avian Research 2021年第1期12卷 63-75页

作者： Daniel F.Perrella Paulo v.Q.Zima Mercival R.Francisco Programa de Pós-Graduacao em Ecologia e Recursos naturais Universidade Federal de SaCarlosWashington Luiz km 235SaCarlos 13565-905Brazil Departamento de Ciências Ambientais Universidade Federal de SaCarlosRod.Joao Leme dos Santos km 110Sorocaba 18052-780Brazil

Background:Patterns of rarity can be explained by reproductive rates,levels of endemism,and habitat specificity,and knowledge on these parameters is important to understand the levels of vulnerability of each species and to formulate conservation ***,we studied nest-site selection and breeding biology of the Atlantic Royal Flycatcher(Onychorhynchus swainsoni),a poorly known vulnerable bird endemic to the Brazilian Atlantic ***:We addressed nest site selection in three different levels:first,we searched for nests near and far from water to investigate whether birds could select water proximities to construct nests;second,we examined if they could select certain streams in detriment of others,and we analyzed the characteristics of used and non-used streams,and third,in streams in which nests were found,we addressed nest site selectivity by comparing a number of parameters between nest sites and random ***,we provide information on breeding biology parameters related to annual ***:During five breeding seasons,we found 23 nests in a well-preserved forest *** of the nests were constructed above water,and they were found in streams that were about 4 m in width,instead of smaller streams with about 1.5 m in *** analyses revealed that within the used streams,nests were constructed in sites with lower vegetation density in relation to random points,while stream width,water speed,and canopy cover presented no significant *** Royal Flycatchers in our study had a 22-day incubation period and 24 to 27-day nestling *** nest survival was comparatively high(62%),but clutch size was small(n=2 eggs)and Along the nesting streams,we found an average of 1.62±0.07 breeding pairs/***:These data suggest that nesting habitat specificity and low annual fecundity are among the factors contributing to the rarity of the Atlantic Royal Flycatcher in large forest continuums and to its absenc

关键词： Atlantic Forest Birds Breeding biology Daily survival rate Endangered species Specialized bird species

Awareness of Patients toward Dental Implants as an Alternative Treatment to Replace Missing Teeth in Kinshasa, D. R. Congo

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Open Journal of Stomatology 2018年第12期8卷 345-353页

作者： em Kalala-Kazadi Patrick Disidi-Yakini Fidèle nyimi-Bushaba Edize Ekofo-Ingaya Augustin Mantshumba-Milolo Unit of Periodontology Department of Dental Medicine Faculty of Medicine University of Kinshasa Kinshasa Congo Oral and Maxillo-Facial Surgery University of Kinshasa and Kinshasa Congo Wuhan University Wuhan China Prosthesis and Orthodontic Service Department of Dental Medicine Faculty of Medicine University of Kinshasa Kinshasa Congo

Background: Dental implant is an artificial root inserted in the jawbone, which restores a lost tooth so that it looks, feels, and is fit like a natural tooth. It is considered to be the best treatment option for single or multiple missing teeth. The aim of this study was to assess the awareness of patients about dental implants as an alternative treatment in Congolese patients. Materials and Methods: A cross-sectional study was conducted in two institutions namely, CBCO Bandal and ngaliema Clinic, from August to December 2017. A total of 450 respondents have participated in the survey. A printed questionnaire comprised of 20 questions in order to evaluate patients dental awareness was used. Gender, level of education, awareness of dental implant and dental implants therapy, sources of information and the expectation about the sources of information were assessed. The collected data were entered in Microsoft Excel 2010 and analyzed by SPSS (IBM SPSS 20.0, Chicago, IL, USA) software. Results: Out of 450 participants, 14.4% were aware of dental implants. The main disadvantage of dental implant was the high cost. When asked about the anchorage, 86% didn’t know where the dental implant was anchored. ninety-two percent didn’t know for how long an implant last, 6% thought that dental implant last for a lifetime. When patients were asked about the sources of information, the dentist (5%) and media (5.5%) were the main sources of information. The majority of patients (88.4%) would like to get information about dental implants from their dentist. Conclusion: Dentists should be more involved in the promotion of information about dental implants as a treatment modality to replace missing teeth.

关键词： Awareness Dental Implant Treatment Modality Oral Rehabilitation