bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular Characterization and Antifungal Susceptibility of Candida Species Isolated From Vulvovaginitis in Jahrom City, South of Iran
Authors: Shokoohi Gholamreza , Rasekh-Jahromi Athar , Solhjoo Kavous , Hasannezhad Arash , Nouripour-Sisakht Sadegh , Ahmadi Bahram , Teymouri Yousef , Shirvani Nazila , Abtahi Fatemeh , Pooransari Parichehr , Ansari Saham
Published: December 2020

Background: Vulvovaginal candidiasis (VVC) is a significant health issue due to Candida spp. Although Candida albicans is considered a major causative agent of vaginal candidiasis, non-albicans species have increased during previous decades. Objectives: This research aimed at molecular identification and assessing antifungal susceptibility of VVC isolated Candida spp. Methods: A professional physician examined two hundred and ninety-five suspected females with vaginitis. The specimens were collected by sterile cotton swabs. Swabs were inoculated on Sabouraud dextrose agar plates and then incubated for 48 - 72 hours at 35°C. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to detect all Candida species. Broth microdilution, according to the M27-A3 and M27-S4 CLSI documents, were employed for determining the antifungal susceptibility tests of caspofungin (CAS), voriconazole (VRC), itraconazole (ITC), fluconazole (FLU), clotrimazole (CLO), ketoconazole (KTO), amphotericin B (AMB), and nystatin (NYS). Results: A total of 295 females suspected of vulvovaginal candidiasis were examined. The culture results were positive in 50.5% (149 of 295) of specimens. According to molecular identification techniques, C. albicans 133/149 (89.2%), C. glabrata 8/149 (5.4%), and C. kefyr 2/149 (1.4%) were the main species. A mixed infection of C. albicans and C. glabrata 6/149 (4 %) was detected. The geometric mean values to all Candida strains were in increasing order as the following: CAS, 0.075 µg/mL; VRC, 0.091 µg/mL; ITC, 0.15 µg/mL; AMB, 0.22 µg/mL; CLO, 0.23 µg/mL; KTO, 0.28 µg/mL; NYS, 0.88 µg/mL; FLU, 1.48 µg/mL. Further, the MIC ranges of all Candida isolates to the tested antifungal agents were in increasing order as follows: CAS: 0.031 - 0.25 µg/mL, KTO and ITC: 0.031 - 2 µg/mL, VRC: 0.031 - 4 µg/mL, CLO and AMB: 0.031 - 8 µg/mL, NYS: 0.06 - 4 µg/mL, and FLU: 0.12 - 128 µg/mL. Conclusions: We reported 1 (7.2 %) C. glabrata isolate resistance to FLU and 2 (14.3%) C. glabrata isolates susceptible-dose-dependent (SDD) to CAS. We also reported 6 (4.5%), 5 (3.8%), and 2 (1.5%) C. albicans resistance to ITC, FLU, and AMB, respectively, but 100% C. albicans susceptible to CAS and VRC.
Synthesis between digital marketing strategies and chess strategies
Authors: Baltezarević Radoslav , Ravić Nenad
Published: December 2020

The development of digital technologies and the emergence of new digital tools has enabled many companies to operate, communicate and build the image of their brands more efficiently in the minds of their consumers. However, in a market characterized by high competition, companies are faced with a need to constantly improve their digital marketing strategies in order to survive at all. There are many practical examplesin which organizations have used chess strategies, which have been developed for hundreds of years, to outsmart their competitors in the market. It is possible to draw a parallel between the strategies of this ancient social game and the business environment, and the knowledge and experience of professional chess players can also help marketing professionals gain a competitive advantage in the market and achieve their business goals in the digital environment. This paper seeks to explore and analyze the possibilities of implementing strategies used in the game of chess in the field of digital marketing and to present the possible benefits that marketers and companies can have from the implementation of these strategies in the modern business environment. The aim of this paper is to collect and analyze information from the existing academic literature on the possibilities of connecting chess and digital marketing strategies and to offer new solutions to marketing experts and companies, which can help them improve their communication with consumers, achieve emotional interaction and create a better image of their brands.
Multiple Myeloma, Version 3.2021, NCCN Clinical Practice Guidelines in Oncology
Authors: Kumar Shaji K. , Callander Natalie S. , Adekola Kehinde , Anderson Larry , Baljevic Muhamed , Campagnaro Erica , Castillo Jorge J. , Chandler Jason C. , Costello Caitlin , Efebera Yvonne , Faiman Matthew , Garfall Alfred , Godby Kelly , Hillengass Jens , Holmberg Leona , Htut Myo , Huff Carol Ann , Kang Yubin , Hultcrantz Malin , Larson Sarah , Liedtke Michaela , Martin Thomas , Omel James , Shain Kenneth , Sborov Douglas , Stockerl-Goldstein Keith , Weber Donna , Keller Jennifer , Kumar Rashmi
Published: December 2020

Multiple myeloma is a malignant neoplasm of plasma cells that accumulate in bone marrow, leading to bone destruction and marrow failure. This manuscript discusses the management of patients with solitary plasmacytoma, smoldering multiple myeloma, and newly diagnosed multiple myeloma.
Impact of Exercise on Chemotherapy Tolerance and Survival in Early-Stage Breast Cancer: A Nonrandomized Controlled Trial
Authors: Kirkham Amy A. , Gelmon Karen A. , Van Patten Cheri L. , Bland Kelcey A. , Wollmann Holly , McKenzie Donald C. , Landry Taryne , Campbell Kristin L.
Published: December 2020

Background: Available preliminary evidence is conflicting on whether exercise can positively influence antineoplastic treatment tolerance and in turn improve survival. Patients and Methods: This study compared chemotherapy treatment tolerance and survival among women receiving adjuvant chemotherapy for early-stage breast cancer who participated in a single-arm trial of supervised aerobic and resistance exercise programming versus a historical cohort that did not receive structured exercise programming. Results: The exercise group (EX; n=73) and control group (CTR; n=85) participants were matched on age and treatment and balanced on medical history, cancer diagnosis, and body mass index. Attendance in the EX group was 64% ± 27% of 3 offered sessions per week. For all chemotherapy agents combined, the relative risk (RR) of a chemotherapy dose reduction (RR, 0.78; 95% CI, 0.54–1.11) or delay (RR, 1.05; 95% CI, 0.62–1.80) did not differ between groups. However, the EX group had reduced relative and absolute risks of a dose reduction in doxorubicin by 60% and 18%, respectively. For all agents combined, there were no differences between groups in risk of anemia, neutropenia, or weight gain. In the EX group, dose reductions due to neutropenia (P=.027), other infections (P=.049), and fatigue (P=.037) were less common, whereas mucositis was more common (P=.023), compared with the CTR group. The EX group had reduced relative and absolute risks of weight gain on the docetaxel + cyclophosphamide regimen by 38% and 30%, respectively. After a median follow-up of 70 months (range, 54–84 months), there was no difference between the EX and CTR groups in disease-free survival events (n=8 [11%] vs n=9 [11%], respectively; log-rank test, P=.78) or overall survival events (n=5 [7%] vs n=6 [7%], respectively; log-rank test, P=.974). Conclusions: Overall, exercise programming during adjuvant chemotherapy does not appear to impact treatment tolerance or survival in women receiving common modern regimens of adjuvant chemotherapy for early-stage breast cancer. However, exercise may provide selective benefits, depending on the treatment regimen received.
Impact of Geography on Care Delivery and Survival for Noncurable Pancreatic Adenocarcinoma: A Population-Based Analysis
Authors: Yee Elliott K. , Coburn Natalie G. , Davis Laura E. , Mahar Alyson L. , Zuk Victoria , Gupta Vaibhav , Liu Ying , Earle Craig C. , Hallet Julie
Published: December 2020

Background: Little is known about how the geographic distribution of cancer services may influence disparities in outcomes for noncurable pancreatic adenocarcinoma. We therefore examined the geographic distribution of outcomes for this disease in relation to distance to cancer centers. Methods: We conducted a retrospective population-based analysis of adults in Ontario, Canada, diagnosed with noncurable pancreatic adenocarcinoma from 2004 through 2017 using linked administrative healthcare datasets. The exposure was distance from place of residence to the nearest cancer center providing medical oncology assessment and systemic therapy. Outcomes were medical oncology consultation, receipt of cancer-directed therapy, and overall survival. We examined the relationship between distance and outcomes using adjusted multivariable regression models. Results: Of 15,970 patients surviving a median of 3.3 months, 65.6% consulted medical oncology and 38.5% received systemic therapy. Regions with comparable outcomes were clustered throughout Ontario. Mapping revealed regional discordances between outcomes. Increasing distance (reference, ≤10 km) was independently associated with lower likelihood of medical oncology consultation (relative risks [95% CI] for 11–50, 51–100, and ≥101 km were 0.90 [0.83–0.98], 0.78 [0.62–0.99], and 0.77 [0.55–1.08], respectively) and worse survival (hazard ratios [95% CI] for 11–50, 51–100, and ≥101 km were 1.08 [1.04–1.12], 1.17 [1.10–1.25], and 1.10 [1.02–1.18], respectively), but not with likelihood of receiving therapy. Receipt of therapy seems less sensitive to distance, suggesting that distance limits entry into the cancer care system via oncology consultation. Regional outcome discordances suggest inefficiencies within and protective factors outside of the cancer care system. Conclusions: These findings provide a basis for clinicians to optimize their practices for patients with noncurable pancreatic adenocarcinoma, for future studies investigating geographic barriers to care, and for regional interventions to improve access.
Diagnosis and Management of Monoclonal Gammopathy and Smoldering Multiple Myeloma
Authors: Schmidt Timothy M. , Callander Natalie S.
Published: December 2020

The presence of monoclonal proteins is common, with a prevalence in the United States around 5% that increases with age. Although most patients are asymptomatic, most cases are caused by a clonal plasma cell disorder. Monoclonal gammopathy of undetermined significance (MGUS) and smoldering multiple myeloma (SMM) are asymptomatic precursor conditions with variable risk of progression to multiple myeloma. In recent years, significant progress has been made to better understand the factors that lead to the development of symptoms and progression to myeloma. This review summarizes the current diagnosis treatment guidelines for MGUS and SMM and highlights recent advances that underscore a shifting paradigm in the evaluation and management of plasma cell precursor conditions.
Nuevas aportaciones a la biografía intelectual de Vicente Aguilera Cerni. Reflexiones en el centenario de su nacimiento
Authors: Frasquet Bellver Lydia
Published: December 2020

Vicente Aguilera Cerni (1920-2005) es uno de los críticos e historiadores del arte españoles del siglo XX con mayor proyección internacional. La reciente investigación llevada a cabo sobre su biografía desvela una serie de datos que nos conduce a reflexionar sobre la visión panorámica de su trayectoria. Aguilera desarrolló una importante labor que debe ser reivindicada, puesto que practicó con firmeza una crítica y una promoción del arte comprometida con su época bajo sus particulares circunstancias. En el centenario de su nacimiento recordamos su figura como teórico del arte y creador del Museu de Vilafamés, uno de los más singulares de nuestro país.
La gestió participativa i el museu de la ciutat. Patrimoni, ciutadania i nodes culturals als barris de Barcelona
Authors: Joan Roca i Albert  , Carme Turégano López
Published: December 2020

Si bé l’urbanisme funcionalista va permetre, fa mig segle, allotjar amb escassos recursos un gran nombre de persones que havien immigrat a la ciutat, també és cert que aquest model no va trigar a mostrar la seva cara poc sostenible. Actualment s’estan recreant els significats dels barris i posant l’esforç en la construcció d’una esfera pública més participativa, on el paper de la cultura és clau en la posada en valor del capital social. Al llarg de l’article, ens referim a algunes museïtzacions de la perifèria urbana de Barcelona que creen noves nodalitats culturals a partir de xarxes on s’entrellacen el patrimoni, la ciutadania i el museu com a espai de participació i coneixement. En aquest context, en un marc de desenvolupament de nous paradigmes culturals, volem centrar-nos en els casos de la Fabra i Coats i del Bon Pastor, que es configuren com a nous nodes culturals en l’articulació de l’Eix Besòs.
Humanitarian Field Practices in the Context of the Syrian Conflict from 2011 to 2018
Authors: Khaldi Hakim
Published: December 2020

How can we go about our work of saving lives when, in Syria, civilians, the
wounded and their families, medical personnel and aid workers are all targets
– whether in areas controlled by the government or those held by the
Kurdish Democratic Union Party (PYD), Islamic State of Iraq and the Levant
(ISIL) or various rebel groups with diverging political agendas? Over the course
of several field missions, the author of this article, a member of
Médecins Sans Frontières (MSF), sought to decipher the political
and military engagements undertaken in different regions of Syria during the war
years. He also factored into his analysis the endless flow of data, information
and positioning being produced and published over this period, because the war
was also fought every day on the internet where the representatives and
ideologists of warring groups, human rights organisations, Syrian diaspora
organisations and spokespersons of the Syrian central authorities were and still
are a permanent presence. Drawing on all these observations and data, the author
relates and analyses the emergency relief activities carried out by MSF in
Syria, how these activities evolved and the conditions in which choices to
intervene and decisions to withdraw were taken.
Biafra, Humanitarian Intervention and History
Authors: Desgrandchamps Marie-Luce , Heerten Lasse , Omaka Arua Oko , O'Sullivan Kevin , Taithe Bertrand
Published: December 2020

This roundtable took place on 16 January 2020, at the occasion of the fiftieth
anniversary of the end of the war in Biafra. It brought together Marie-Luce
Desgrandchamps, Lasse Heerten, Arua Oko Omaka and Kevin O’Sullivan. The
roundtable was organised and chaired by Bertrand Taithe, University of
Manchester.
Pārvaldīšanas un apsaimniekošanas procesu īstenošanas metodoloģiskie risinājumi daudzdzīvokļu dzīvojamām mājām mājokļu politikas kontekstā
Authors:   , Pļaviņa Baiba
Published: December 2020

Promocijas darbs ir patstāvīgs zinātnisks pētījums, izstrādāts Rīgas Tehniskās universitātes Inženierekonomikas un vadības fakultātes Būvuzņēmējdarbības un nekustamā īpašuma ekonomikas institūta Būvuzņēmējdarbības un nekustamā īpašuma ekonomikas un vadīšanas katedrā Latvijas Republikas ekonomikas zinātņu grāda iegūšanai. Promocijas darba zinātniskais vadītājs ir profesore Dr. oec. Ineta Geipele. Promocijas darba mērķis ir izstrādāt mājokļu politikas un DDzM pārvaldīšanas un apsaimniekošanas darbību informācijas savstarpējas apmaiņas sistēmas procesu īstenošanas metodoloģisko risinājumu valsts, pašvaldību un pārvaldīšanas uzņēmumu saimnieciskās darbības un stratēģiskās plānošanas procesu pilnveidošanai. Promocijas darbam ir ievads, trīs daļas, deviņas nodaļas, četras apakšnodaļas, secinājumi un priekšlikumi, izmantotās literatūras un avotu saraksts, 23 pielikumi. Promocijas darba ievadā tiek raksturota izvēlētās tēmas aktualitāte, izvirzīta pētījuma hipotēze, definēti darba mērķi un to sasniegšanai risināmie uzdevumi, pētījuma objekts un priekšmets, pētījuma metodoloģiskais raksturojums, darba ierobežojumi, raksturota pētījuma teorētiskā nozīme un zinātniskā novitāte, kā arī pētījuma rezultātu aprobācija un praktiskais lietojums. Promocijas darbam pirmā daļā analizēti DDzM pārvaldīšanas un apsaimniekošanas plānošanas teorētiskie aspekti. Otrajā daļā veikts DDzM pārvaldīšanas un apsaimniekošanas problēmu analītiskais izvērtējums. Trešajā daļā apspoguļoti mājokļu politikas un DDzM pārvaldīšanas un apsaimniekošanas procesu ietekmes indikatoru mijsakarības pētījuma rezultāti un piedāvāts mājokļu politikas un DDzM pārvaldīšanas un apsaimniekošanas savstarpējās informācijas plūsmas pilnveidošanas metodoloģiskais risinājums. Promocijas darba nobeigumā sniegti secinājumi un priekšlikumi mājokļu politikas un DDzM pārvaldīšanas un apsaimniekošanas plānošanas informācijas plūsmas risinājumu pilnveidošanai.
An adaptive chattering-free variable structure control method for uncertain time-variant chaotic systems
Authors: Yu Dong-Chuan  , Meng Qing-Hao  ,   天津大学自动化系，天津300072
Published: December 2020

The conventional variable structure control(VSC) methods for controlling chaos have some drawbacks, such as high_frequency chattering and the need of a prior knowledge about the upper bound of the uncertainty. Trying to solve the drawbacks, we proposed an adaptive chatteringfree variable structure control(ACFVSC) method for controlling a class of uncertain timevariable chaotic systems towards arbitrarily desired trajectory. The ACFVSC method not only eliminates the chattering phenomenon and tracks arbitrarily desired trajectory asymptotically, but also removes the prior knowledge about the upper bound of uncertainty. Both the asymptotic tracking analysis of ACFVSC and simulation results show that the arbitrarily desired tracking accuracy can be achieved within a finite time if the parameter of ACFVSC controller is appropriately set.
Theoretical analysis of tunable wavelength conversion based on FWM in semiconductor fiber ring laser
Authors: Li Pei-Li  , Zhang Xin-Liang  , Chen Jun  , Huang Li-Rong  , Huang De-Xiu  ,   华中科技大学光电子工程系，武汉  430074
Published: December 2020

In this paper, a comprehensive broad_band dynamic model of tunable wavelength converter based on four_wave mixing in semiconductor fiber ring laser is presented. Critical factors, e.g., the materal gain profile, the longitudinal variation of the optical field, and the broad_band spontaneous noise emission are considered in the model. By numerical simulation, the effects of the input signal power, injection current, the coupling of the output coupler and the lasing wavelength on the performance of the wavelength converter are investigated. Numerical results are in agreement with the experimental results in the literature
Dispersion and polarization properties of near-rectangle core photonic crystal fibers
Authors: Lou Shu-Qin  , Ren Guo-Bin  , Yan Feng-Ping  , Jian Shui-Sheng  ,   北京交通大学电子信息工程学院，全光网络与现代通信网教育部重点实验室，北京100044
Published: December 2020

Dispersion and polarization properties of near_rectangle core photoric crystal fibers (PCFs) were analyzed with a full vector model. The numerical results show that the modal birefringence of near_rectangle core PCF is at least one order of magnitude higher than the conventional elliptical polarization_maintaining fibers (PMFs). In order to obtain higher birefringence, an efficient way is to increase the relative hole diameter. Zero walk_off point occurs at the longer wavelength than that of convention elliptical PMF. With increasing hole pitch, the walk_off curve and zero walkoff point would shift towards the longer wavelength region. The corresponding wavelength of zero walkoff point is in proportion to the size of the hole pitch. The occurrence of zero walkoff point can efficiently restrain the first_order polarization mode dispersion. Through choosing the suitable structural parameter of near_rectangle core PCF, we can get the more flexible dispersion properties. The approximate 400nm ultra_flatten dispersion was gotten near the wavelength 155μm for a nearrectangle core PCF with Λ=2μm and d/Λ=03 This fiber has a number of potential applications in polarization control, dispersion control and management.
Investigation of nonlinear self-consistent interaction progress between microwa ve and electron beam in RF cavity
Authors: Li Zheng-Hong  , Huang Hua  , Chang An-Bi  , Meng Fan-Bao  ,   中国工程物理研究院应用电子学研究所，绵阳  621900
Published: December 2020

The motion of electrons is affected by microwave in RF cavity. Meanwhile electrons can also generate radiation and have influence on microwave in the cavity. Ac cording to Maxwell theory, RF field in the RF cavity can be expressed by modes. So equations about such actions are established according to Maxwell theory and Lorentz force acting on electrons in the cavity. These equations are also called self-consistent equations for action between microwave and electron beam in RF cavity. Based on the equations, the single-gap RF cavity is investigated one- dimensionally (including how microwave increases and saturates in the cavity) an d the factors influencing the output power are also studied. It is concluded tha t nonlinear action is very important, and that output power is not only determin ed by cavity structure but also by the beam modulation.
Study on structure relaxation of Zr5555Cu3030Al10 10Ni55bulk amorphous alloy
Authors: Liu Yi  , Wu Zi-Fang  , Liu Lin  , Zhang Tao  ,   (1)北京航空航天大学材料科学与工程学院，北京  100083; (2)华中科技大学塑性成型模拟及模具技术国家重点实验室，武汉  430074; (3)中国科学院上海应用物理研究所,上海  201800
Published: December 2020

The structure relaxation of Zr5555Cu3030Al1010Ni55 bulk amorphous alloy annealed at 340℃ for different times have been investigated by synchrotron radiation small angle x-ray scattering and differential scanning calorimetr y. Annealing time dependence of electronic density fluctuation in the amorphous alloy and apparent activation energies for the enthalpy relaxation were presente d and discussed. The experimental results show that electronic density fluctuati ons increase first and then decrease with increasing annealing time, while the a pparent activation energy for the enthalpy relaxation exhibits an opposite chang e, i.e., decreases first and then increases. Both indicate the transformatio n from the liquid-like region to the solid-like region in amorphous alloy duri ng annealing.
Effects of the trapping effect on LHCD in tokamak
Authors: Jiao Yi-Ming  , Long Yong-Xing  , Dong Jia-Qi  , Shi Bing-Ren  , Gao Qing-Di  ,   (1)电子科技大学光电信息学院，成都  610054;核工业西南物理研究院，成都  610041; (2)核工业西南物理研究院，成都  610041
Published: December 2020

A Fokker-Planck study is carried out for tokamak lower hybrid current drive (LHCD)by considering the wave absorption in the presence of trapping effect situation. This Fokker-Planck code is developed based on FASTFP, and is suitable for various auxiliary heating and current drive situations. The energy loss mechanism through anomalous transport is modeled by using a suitable loss term. In the h eating phase, the electron distribution deviates clearly from the Maxwellian, an d this results in nonlinear absorption characteristics. As an electrostatic forc e, the lower hybrid wave makes the trapped electrons untrapped, and the wave los ses its energy,which cuts down the LHCD efficiency 30%.
Investigation on the dye-sensitized solar cell
Authors: Dai Song-Yuan  , Kong Fan-Tai  , Hu Lin-Hua  , Shi Cheng-Wu  , Fang Xia-Qin  , Pan Xu  , Wang Kong-Jia  ,   中国科学院等离子体物理研究所,合肥  230031
Published: December 2020

The key technologies in dye-sensitized solar cell, including nanoporous TiO２2 film, dye-sensitizer, electrolyte, platinum catalysis, and TCO glass, have bee n investigated, and we also optimized the different technologies with assemblyin g the small area dye-sensitized solar cells. About 9% photo-electric conversion efficiency has been demostrated in our lab under AM1.5 solar simulator. Our results show that there would be a possibility for commercial production based on our technologies.
Total cross sections for the scattering of electrons from methane and chloromethanes at intermediate and high energies
Authors: Shi De-Heng  , Sun Jin-Feng  , Yang Xiang-Dong  , Zhu Zun-Lue  , Liu Yu-Fang  ,   (1)河南师范大学物理系，新乡  453007; (2)河南师范大学物理系，新乡  453007;四川大学原子与分子物理研究所，成都  610065; (3)河南师范大学物理系，新乡  453007;四川大学原子与分子物理研究所，成都  610065;空军第一航空学院基础部，信阳  464000; (4)四川大学原子与分子物理研究所，成都  610065
Published: December 2020

A complex optical model potential modified by incorporating the concept of bonde d atom, which takes into consideration the overlapping effect of electron clouds between two atoms in a molecule, is employed to calculate the total cross sect ions for electron scattering from methane and chloromethanes（CH4 , CCl4, CHCl3, CH2Cl2 and CH3Cl）over the incident energy r ange 30—5000eV by using additivity rule model at Hartree_Fock level. In the stu dy, the complex optical model potential composed of static, exchange, correlatio n polarization plus absorption contributions uses the bonded_atom concept. The quantitative molecular total cross_section results are compared with the experim ental data and other calculation results wherever available, and good agreement is obtained. It is shown that the additivity rule model together with the comple x optical potential model modified by incorporating the concept of bonded atom c an give better results than that unmodified. So, the introduction of the bonded_ atom concept in the complex optical model potential improves the accuracy of the total cross_section calculation results of electrons from molecules.
Dynamical behavior of ultrashort pulse laser in para-nitroaniline molecules
Authors: Li Hong-Yu  , Zhao Ke  , Pan Rui-Qin  , Sun Yuan-Hong  , Wang Chuan-Kui  ,   山东师范大学物理与电子科学学院，济南  250014
Published: December 2020

The electronic structures and dipole moments of para- nitroaniline molecule are calculated by use of density functional theory at ab initio level. We then inve stigate theoretically the interaction between the ultrashort pulse laser and the para-nitroaniline molecule medium by solving the full Maxwell-Bloch equations. The effects of permanent dipole moments on the pulse reshaping, the spectrum com ponents, and the evolutions of energy state populations are discussed in detail. The results show that the standing slowly varying envelope and the rotating-wav e approximations fail to give a good description for the propagation of an ultra short pulse in the molecule medium. Furthermore, the dipole moments of the molec ule make the propagation deviate from the area theorem further and make the pul se split more quickly. When the pulse with the excitation energy of the charge-t ransfer state propagates in the para-nitroaniline molecule medium, the second-ha rmonic spectral component appears obviously and becomes stronger as the propagat ing distance increases, which displays the high two-photon absorption properties of the molecule.
Synthesis of β-GaN nanocrystals with a cubic structure by gas-phase chemical reaction
Authors: Fang Kun  , Gao Shan-Min  , Qiu Hai-Lin  , Cao Chuan-Bao  , Zhu He-Sun  ,   (1)北京理工大学材料科学研究中心, 北京  100081; (2)北京理工大学材料科学研究中心, 北京  100081;北京科技大学材料科学与工程学院, 北京  100083; (3)烟台师范学院化学与材料科学学院,烟台  264025
Published: December 2020

β-GaN nanocrystalline have been successfully synthesized from the nitridation of GaP nanocrystalline at low temperatures by gas_phase chemical reaction. The s tarting GaP nanocrystalline has a large specific surface and a high reactivity that can reduce remarkably the difficulty of nitridation. The results of GaP nan ocrystalline in N2 at different heating rates support the fact that β-GaN nan ocrystalline can form in GaP nanocrystalline via N-P metathesis gas_phase chemic al mechanism. The mechanism is different when different heating rate was used. T his method is very simple and is used generally to synthesize β-GaN nanopartic les or nanorods.
Resistivity of polyaniline nanotubes doped with naphthalene sulfonic acid: dependence on moisture and ethanol
Authors: Zhou Yun  , Long Yun-Ze  , Chen Zhao-Jia  , Zhang Zhi-Ming  , Wan Mei-Xiang  ,   (1)中国科学院化学研究所分子科学中心，有机固体实验室，北京  100080; (2)中国科学院物理研究所极端条件物理实验室，北京  100080
Published: December 2020

The moisture and ethanol dependences of electrical properties of polyaniline (PANI) nanotubes doped with naphthalene sulfonic acid (NSA) are reported. The experiments were carried out in a temperature range from 80 to 300K. On the basis of analyzing the characteristics of the samples, we suggest that the resistance of the samples is dominated by the contact resistance between the PANI nanotubes, and the observed lnR(T)∝T-1/2 relation is explained in terms of the charge-energy-limited tunneling (CELT) model. The presence of water or ethanol molecules increases the conductivity, which is ascribed to the enhancement of charge carrier transfer and contact interface between the nanotubes upon exposure to water and ethanol. However, the extent of change during exposure to water and ethanol can be attributed to the differences in their chemical structures as well as their physicochemical properties.
Conductance peak with Zeeman splitting in normal metal-insulator-ferromagnet/superconductor tunnel junctions
Authors: Li Xiao-Wei  ,   淮阴师范学院物理系，淮安  223001
Published: December 2020

Using Bogoliubov-de Gennes equations, we obtain the self-consistent equation in a ferromagnetic superconductor. Taking into account the rough interface scatteri ng effects, in the framework of the Blonder-Tinkham-Klapwijk model，we present t he differential conductance of the normal metal-insulator-ferromagnet/supercondu ctor (N/I/FS ) tunnel junctions. It is shown that the exchange energy Eh i n FS can lead to the Zeeman splitting of the conductance peaks;the energy differ ence between the two splitting peaks is equal to 2Eh. The differentia l con ductances in N/I/FS are suppressed by the barrier strength and rough interface s cattering strength.
Ground state properties of the one-dimensional spin-Peilers model with symmetric and antisymmetric superexchange interactions
Authors: Liu Hai-Lian  , Wang Zhi-Guo  , Chen Yu-Guang  , Shi Yun-Long  , Chen Hong  ,   (1)同济大学波耳固体物理研究所，上海  200092; (2)同济大学波耳固体物理研究所，上海  200092;雁北师范学院物理系，大同  037000
Published: December 2020

Ground-state properties of the one-dimensional spin-Peilers model with Dzyaloshi nskii-Moriya（DM）interaction and Kaplan-Shekhtman-Entin-Wohlman-Aharony（KSEA） interactions are studied by Lanczos numerical method. It is shown that the DM interaction acts against dimerization when the DM interaction is irrelative to dimerization. On the other hand, the DM interaction is favorable for dimerization when DM interaction depends on the dimerization. Otherwise, the KSEA interactio n is always against dimerization. The KSEA interaction affects the contribution of the DM interaction to dimerization, and even offsets the effect of DM interac tion. The dimerization vanishes when DM and KSEA interactions are large enough i n some special cases.
Optical emission diagnosis of helicon-wave-plasma-enhanced chemical vapor deposition of nanocrystalline silicon
Authors: Yu Wei  , Wang Bao-Zhu  , Yang Yan-Bin  , Lu Wan-Bing  , Fu Guang-Sheng  ,   河北大学物理科学与技术学院,保定  071002
Published: December 2020

Optical emission spectroscopy (OES) is used to diagnose the active species emission in the helicon_wave_plasma_enhanced chemical vapor deposition of nanocrystalline silicon. The effects of the experimental parameters on OES intensity of SiH *, Hβ and Hα have been studied. Ｅxperiment r esults indicate that the ma gnetic field confinement makes the reactant molecules dissociate efficiently. Ap propriate hydrogen dilution can increase the density of hydrogen active species, while higher dilution makes the concentration of silicon_contained active spec ies decrease. The density of the active species increases monotonically with in creasing input rf power, and a relatively higher concentration of hydrogen act ive species reaching the substrate surface can be achieved. Experiment results obtained are analyzed based on the dispersive relation and the characteristic o f the helicon wave plasma, which offer the basic data for the understanding of t he process of nanocrstalline silicon deposition and adjusting its experimental p arameters.
Effects of mass variation on form invariance and conserved quantity of mechanical systems
Authors: Ge Wei-Kuan  ,   湖州师范学院理学院,湖州  313000
Published: December 2020

The effects of mass variation on form invariance and conserved quantity of mechanical systems are studied. The criterion of the form invariance for constant mass and variable mass systems is given.By comparing the two criterion equations, the condition under which the form invariance is kept is obtained. The condition under which two systems possess the same conserved quantity is also given. An e xample is given to illustrate the application of the result.
Bound states for a kind of relativistic non-harmonic oscillator systems
Authors: Li Ning  , Ju Guo-Xing  , Ren Zhong-Zhou  ,   (1)南京大学物理系，南京  210008; (2)南京大学物理系，南京  210008;兰州重离子加速器国家实验室原子核理论中心，兰州  730000
Published: December 2020

For a three-dimensional non-harmonic oscillator potential 12r2+A2r 2, the s-wave bound solutions of both Dirac equation and Klein-Gordon equation are giv en when the scalar potential is equal to the vector potential. We find that the radial component equations for both two-dimensional Dirac equation and three-dimensional one are the same when the scalar potential equals to the vector potenti al, and the corresponding s-wave bound solutions for the two-dimensional system are also obtained.
Monte Carlo simulation for diffuse backscattering of polarized light from poly-disperse highly dense media
Authors: Wang Ling  , Xu Zhi-Hai  , Feng Hua-Jun  ,   (1)浙江大学现代光学仪器国家重点实验室,杭州  310027，中国; (2)浙江大学现代光学仪器国家重点实验室,杭州  310027，中国;北海道大学电子科学研究所，札幌  0600812，日本
Published: December 2020

A Monte Carlo simulation model for the diffuse backscattering of the polarized l ight from the poly_disperse highly dense media is developed and the effective fr ee pathlength distribution function of the poly_disperse system is given. Simula tion is conducted for the mono_disperse polystyrene suspensions with particle si zes of radii 50 and 550nm, and poly_disperse suspensions containing the above tw o particles with the volume fraction ratios of 4:1, 1:1 and 1:4 The relation b etween the spatial intensity variations of the light diffuse backscattering patt ern and the volume fraction ratio of the poly_disperse suspensions is analyzed q ualitatively.
Z scan analysis for near top-hat beams
Authors: Yang Xin-Jiang  , Zang Wei-Ping  , Tian Jian-Guo  , Liu Zhi-Bo  , Zhou Wen-Yuan  , Zhang Chun-Ping  , Zhang Guang-Yin  ,   南开大学物理科学学院光子学中心,天津  300071
Published: December 2020

The Z scan theory of thin optically nonlinear medium, by using the fast Hank el transform,is analyzed. The characteristics of Z scan curves under near to p-hat beams are discussed. Meanwhile, the influence of the ratio (diaphragm-gird ling ratio) of the limiting diaphragm radius to the radius of expanded beams on normalized transmittance using near top-hat beams under closed-aperture is analy zed. Through theoretical analysis, the ratio with the best sensitivity is given. Finally, the influence of the size of the far-field diaphragm on normalized tra nsmittance under the experimental configuration with the best sensitivity is ana lyzed.
A singularity-free solution of Friedmann universe in the discrete spacetime
Authors: Chen Guang  ,   东华大学信息学院，上海  200051
Published: December 2020

An idealized Friedmann cosmological model in the discrete spacetime is consist of collection of dust particles obtained in paper［1］ and proved to be singu larity-free.
Phase-shift algorithm research based on multiple-beam interference principle
Authors: Luo Zhi-Yong  , Yang Li-Feng  , Chen Yun-Chang  ,   中国计量科学研究院,北京  100013
Published: December 2020

Aiming at the application of precision measurement of length, the phase-shift a lgorithm including algorithm error and optimum range of the phase-shift step wa s studied by using the multiple-beam interference principle in this paper. We have derived an accurate formula for the intensity distribution of multiple-be am interference (multiple reflection by and transmission through the optical s urface) in the basic principle of interference optics. Based on this formula and the numerical analysis technique, we have found the optimum value of the phase-shift step and the applicable range of the initial phase difference between in terference beams by using the precision measurement of length with Fizeau inter ferometer.We also found the respective relationships between the original phase error and the phase of four-step algorithm (and of the five-step algorithm) d ue to the intensity error from cosine dependence. We have assessed the uncertain ty from several main error sources of the multiple-beam interference.
Near Gaussian approximation for light propagation in the intermittent atmospheric turbulence
Authors: Chen Jing-Yuan  , Chen Shi-Gang  , Wang Guang-Rui  ,   (1)北京应用物理与计算数学研究所，北京 100088; (2)中国工程物理研究院北京研究生部，北京 100088
Published: December 2020

Intermittency is an essential property of turbulent atmosphere, and is one of the core content in modern turbulence theory. But, when we consider the problem of wave propagation in turbulent atmosphere, we always evade this property and use the assumption of a Gaussian probability distribution of dielectric permittivity fluctuation. In this paper, we discussed the intermittent effects on light propagation in turbulent atmosphere. According to the fact that the variance of dielectric permittivity fluctuation is very small, we explicitly expanded the equations of optical statistical moments to the fourth-order cumulant functions and considered their solutions. As for the second-order moment which is important i n optical applications, we have analyzed it emphatically by the hierarchical str uctures model. Our results indicate that the optical effects of turbulent interm ittency are negligible and the conventional Gaussian assumption is rational.
Third harmonic generation in plasma channels in air induced by intense femtosecond laser pulses
Authors: Hao Zuo-Qiang  , Zhang Jie  , Zhang Zhe  , Xi Ting-Ting  , Zheng  Zhi-Yuan  , Yuan Xiao-Hui  , Wang Zhao-Hua  ,   (1)中国科学院物理研究所光物理院重点实验室，北京  100080; (2)中国科学院物理研究所光物理院重点实验室，北京  100080;中国科学院西安光学精密机械研究所瞬态光学技术国家重点实验室，西安  710068
Published: December 2020

Strong third-order harmonic (TH) emission is observed from long plasma channels formed when intense femtosecond laser pulses propagate in air. The conversion efficiency between the fundamental wave and the TH emission is roughly constant over the length of the plasma channels. The divergence angle of the TH emission in the conical emission of the plasma channels is also investigated, which is in good agreement with calculations.
Simulation of step response of silane low-temperature pasma(1)
Authors: Yang Jing  , Li Jing-Zhen  , Sun Xiu-Quan  , Gong Xiang-Dong  ,   深圳大学工程技术学院，深圳  518060
Published: December 2020

Understanding of the transient response of electronegative radio-frequency glow plasmas is important for process control, better selectivity etch technology and charge free etching. We have investigated the step responses of RF(1356MHz) silane gas plasmas at a pressure of 05 Torr(05×10333Pa). The result showed that, when the power voltage changed stepwise from 550V to 350V, a steady sta te pulsed plasma oscillation at a few kHz appeared. The transient behavior and o scillation were interpreted in terms of the transport and chemistry of charge ca rriers in the plasma.
Preparation of Al2O3 ceramic coating by electrolytic plasma processing and its properties
Authors: Gu Wei-Chao  , Shen De-Jiu  , Wang Yu-Lin  , Chen Guang-Liang  , Feng Wen-Ran  , Zhang Gu-Ling  , Liu Chi-Zi  , Yang Si-Ze  ,   (1)燕山大学亚稳材料制备技术与科学重点实验室，秦皇岛  066004; (2)中国科学院物理研究所，北京  100080; (3)中国科学院物理研究所，北京  100080;燕山大学亚稳材料制备技术与科学重点实验室，秦皇岛  066004
Published: December 2020

Metallurgically bonded Al2O3 ceramic coating was prepared on steel surface with the combined method of arc spraying and electrolytic plasma processing. The composition and microstructure of the ceramic coating were analyzed by x-ray dif fraction, scanning electron microscony and EDS. The corrosion resistance and wea r resistance of the ceramic coating were measured. The results show that the cer amic coating is compact and mainly composed of α-Al2O3, γ-Al2O3, θ-Al2O3 and a little of a morphous phase. The duplex coating shows favorable corrosion resistance and wear resistance properties.
Conditions for formation of misfit dislocation in epitaxial films — a molecular dynamics study
Authors: Zhou Nai-Gen  , Zhou Lang  ,   南昌大学材料科学与工程学院，南昌  330047
Published: December 2020

Molecular dynamics simulations for the formation of misfit dislocation in compre ssive epitaxial aluminum films have been carried out. The potential in an embed ded atom method (EAM) is employed. The results show that, in long relaxation at 500K, the films with a perfect surface remain dislocation-free in thickness ran ge of 9—80 atomic layers, which corresponds to 3—40 times of its thermodynami c critical thickness. However, with the presence of small boss or pit of one-at om high and three-atom wide on surface, misfit dislocations form readily in film s of 15 atomic layer thick. In dynamic growth of a preset 9 atomic layer thick film, under deposition, the surface develops significant roughness naturally, l eading to rapid formation of misfit dislocation. The dislocations formed under the three conditions are all complete edge dislocations, with their Burgers vec tors parallel to the axis of misfit. Analysis revealed that, under compression , the micro-boss induces squeezing-out of atoms beside, leading to nucleation of a dislocation, and the micro-pit is directly reshaped to a nucleus of dislocat ion semi-loop.
Circular magnetization processes in amorphous and nanocrystalline soft magnetic wires
Authors: Li Yin-Feng  , Yin Shi-Zhong  , Vázquez M.  ,   (1)Instituto de Ciencia de Materiales de Madrid,CSIC,Cantoblanco,28049,Madrid,Spain; (2)Instituto de Ciencia de Materiales de Madrid,CSIC,Cantoblanco,28049,Madrid,Spain;邢台学院物理系,邢台  054054; (3)邢台学院物理系,邢台  054054
Published: December 2020

The changes of circular permeability with the circular magnetic field and frequency, in amorphous and nanocrystalline soft magnetic wires with different magnetic strucutre, have been determined from the measurements of impedance. The circular magnetization curve was obtained by using the Chen et als formulas. We found that these formulas are not suitable for the process with very large magnetic losses, so a general expression has been developed. Additionally, different circular coercivity mechanisms in the wires with longitudinal or transversal domain strucutre were deduced from analyzing the circular-field-dependent complex circular permeability. Finally, the frequency effect is also discussed.
Influence of grain alignment degree on the magnetic properties for single-phase nanocrystalline Pr2Fe14B magnets
Authors: He Shu-Li  , Zhang Hong-Wei  , Rong Chuan-Bing  , Chen Ren-Jie  , Sun Ji-Rong  , Shen Bao-Gen  ,   (1)首都师范大学物理系，北京  100037;中国科学院物理所磁学国家重点实验室，北京  100080; (2)中国科学院物理所磁学国家重点实验室，北京  100080
Published: December 2020

The single-phase nanocrystalline Pr2Fe14B magnets composed of cubic-shaped and irregular-shaped grains is built. The magnetic hysteresis loops are simulated by micromagnetism finite element method. The remanence, coercivity and maximum energy product decrease with deteriorated grain alignment. Attributed to strong intergrain exchange coupling (IGEC), the variation of magnetic proper ties with alignment degree is significantly affected by the average grain size i n nanocrystalline magnets. The investigation shows the increase of coercivity wi th improved grain alignment in nanocrystalline magnets, which is completely diff erent from the phenomena in sintered magnets.
Characteristic of nonlinear system stochastic resonance in the neighbourhood of bifurcation point
Authors: Zhang Guang-Jun  , Xu Jian-Xue  ,   西安交通大学建筑工程与力学学院，710049
Published: December 2020

This paper studied the characteristics of stochastic resonance in the neighborhood of bifurcation point of two nonlinear dynamic systems, the pitchfork bifurcation system and FitzHughNagumo (FHN) cell model. The results of research show t hat the two nonlinear dynamic systems have the same bifurcation characteristic o f transition from one to two attractors (or from two to one attractors) when the bifurcation of each system occurs, that is, in the neighborhood of the bifurcat ion point there exist attractors before and after bifurcation on the both sides of the bifurcation point. Under the perturbation of noise, a transition may occu r between the two coexisting attractors on the right side of the bifurcation poi nt, in a way like the mechanism of traditional stochastic resonance; moreover,an other transition may also occur among the three attractors (one before bifurcati on and two after it) on two sides of the bifurcation point, which can induce sto chastic resonance alone. When the two types of transitions occur, the stochastic resonance induced by the second type of transition continues in a wide intensit y range of noise, which causes the first type of transition; and the stochastic resonance induced by the first type of transition stops in a rather small range of the noise intensity,and then causes the second type of transition.
Study on the dependence of the contrast of image speckles produced by strong scattering-object on random surface and imaging system
Authors: Song Hong-Sheng  , Cheng Chuan-Fu  , Zhang Ning-Yu  , Ren Xiao-Rong  , Teng Shu-Yun  , Xu Zhi-Zhan  ,   (1)山东建筑工程学院,济南  250014; (2)山东师范大学物理系,济南  250014; (3)中国科学院上海光学与精密机械研究所,上海  201800; (4)中国科学院上海光学与精密机械研究所,上海  201800;山东师范大学物理系,济南  250014
Published: December 2020

We study the statistical properties of the image speckles produced by strongscattering objects in the 4f optical imaging system. Using the generic expression of the complex amplitude of speckles and the approximation of the doubleexponential function, we first obtain the ensemble average of the speckle intensity. Then we derive the variance of the speckle intensity based on the rotational transformation of the real and imaginary parts of the complex amplitude of speckles. We finally obtain the expression for the contrast of the speckles, which is explicitly related to the statistical parameters of random surface and to the parameters of the imaging system. Our results are an obvious improvement compared with those reported in the literature, where the relations including such implicit quantities as the average size of the scattering grains of the random surface and the number of scattering grains are usually used. The results of this paper would be helpful for the characterization of random surface by speckle contrast.
Rabi flopping in a V-type three-level system with two orthogonal eigenstates
Authors: Zhou Hui-Jun  , Liu Shao-Ding  , Wang Qu-Quan  , Zhan Ming-Sheng  , Xue Qi-Kun  ,   (1)武汉大学物理系,武汉  430072; (2)武汉大学物理系,武汉  430072;中国科学院物理研究所国际量子结构中心,北京  100080; (3)中国科学院武汉物理与数学研究所,武汉  430071; (4)中国科学院物理研究所国际量子结构中心,北京  100080
Published: December 2020

The oscillation characteristics of populations in two orthogonal energy substates of semiconductor quantum dots (SQDs) excited by linearly polarized monochromatic pulse field were discussed. With rotatingwave approximation, the nondamped solutions of the dynamic population equations with resonance excitation were deduced. The effective transition dipole moments and effective input pulse area were introduced and their expressions were also given. Theoretical analysis showed that the amplitude and frequency of the population oscillation on the substates can be manipulated by adjusting the original conditions and the polarization angle of excitation field.
Experimental and theoretical study on gain dynamics of SOA
Authors: Dong Jian-Ji  , Zhang Xin-Liang  , Huang De-Xiu  ,   华中科技大学光电子工程系，武汉  430074
Published: December 2020

A new conception of effective gain recovery time of semiconductor optical amplifier (SOA) was brought forward, and a simple analytical expression for the gain r ecovery time was derived. Factors that affect gain recovery time, such as bias c urrent, probe power and device length were analyzed respectively on the base is of application of SOA to the cross gain modulation wavelength conversion. Gain r ecovery time was measured experimentally. It is shown that the experimental resu lt agrees well with the theoretical calculation.