cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Plants adapted to arid areas: specialized metabolites
Creators: name: Zahedi, Seyed Morteza
name: Karimi, Mahdieh
name: Venditti, Alessandro
Publisher: name: Taylor & Francis
Year: 2019
Subjects: subject: Medicine
subject: Cell Biology
subject: Genetics
subject: FOS: Biological sciences
subject: Molecular Biology
subject: Biotechnology
subject: Ecology
subject: 110309 Infectious Diseases
subject: FOS: Health sciences
subject: Plant Biology
subject: 60506 Virology
subject: Computational Biology

description: Drought stress affects growth, morphological and biochemical properties in plants. To develop resistance and adapt to drought, plants need metabolic changes. Adaptations to stress involve changes to gene expression that activate metabolic processes that promote drought resistance and that may include biosynthesis and accumulation of specialized metabolites. Such adaptations in specialized metabolism may be important mechanisms leading to plant stress resistance and involve production of phenolics, flavonoids, terpenoid and nitrogen containing compounds that are species and genotype specific. Most plants having special metabolites to adapt to drought stress belong to different botanical families. C3, C4 and CAM plants, apply both morphological and metabolic mechanisms to adapt to drought as well as to accumulate specialized metabolites. Generally, medicinal plants increase their functional metabolites content, when exposed to drought stress. During drought stress, transcription factors and related pathways for biosynthesis of phenolics, flavonoids, anthocyanins as well as for stress jasmonate and abscisic acid stress hormones are activated.
On Asymptotic Quantum Statistical Inference
Creators: name: Gill, Richard D.
name: Guta, Madalin
Publisher: name: arXiv
Year: 2011
Subjects: subject: Quantum Physics (quant-ph)
subject: Statistics Theory (math.ST)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We study asymptotically optimal statistical inference concerning the unknown state of $N$ identical quantum systems, using two complementary approaches: a "poor man's approach" based on the van Trees inequality, and a rather more sophisticated approach using the recently developed quantum form of LeCam's theory of Local Asymptotic Normality.
description: 34 pages. to appear in `From Probability to Statistics and Back: High-Dimensional Models and Processes'. A Festschrift in Honor of Jon Wellner. Edited by Banerjee, M., Bunea, F., Huang, J., Maathuis, M. and Koltchinskii, V. extension of a previous paper arXiv:math/0512443
Partially Observable Markov Decision Processes with Behavioral Norms
Creators: name: Nickles, Matthias
name: Rettinger, Achim
Publisher: name: Karlsruhe
Year: 2009
Subjects: Norms
Partially Observable Markov Decision Processes
Deontic Logic
Propositional Dynamic Logic

description: This extended abstract discusses various approaches to the constraining of Partially Observable Markov Decision Processes (POMDPs) using social norms and logical assertions in a dynamic logic framework. Whereas the exploitation of synergies among formal logic on the one hand and stochastic approaches and machine learning on the other is gaining significantly increasing interest since several years, most of the respective approaches fall into the category of relational learning in the widest sense, including inductive (stochastic) logic programming. In contrast, the use of formal knowledge (including knowledge about social norms) for the provision of hard constraints and prior knowledge for some stochastic learning or modeling task is much less frequently approached. Although we do not propose directly implementable technical solutions, it is hoped that this work is a useful contribution to a discussion about the usefulness and feasibility of approaches from norm research and formal logic in the context of stochastic behavioral models, and vice versa.
Entangling two Bose Einstein condensates in a double cavity system
Creators: name: Kumar, Tarun
name: Bhattacherjee, Aranya B
name: ManMohan
Publisher: name: arXiv
Year: 2010
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: We propose a scheme to transfer the quantum state of light fields to the collective density excitations of a Bose Einstein condensate (BEC) in a cavity. This scheme allows to entangle two BECs in a double cavity setup by transferring the quantum entanglement of two light fields produced from a nondegenerate parametric amplifier (NOPA) to the collective density excitations of the two BECs. An EPR state of the collective density excitations can be created by a judicious choice of the system parameters.
description: 3 figures
Fast evaluation of far-field signals for time-domain wave propagation
Creators: name: Field, Scott E.
name: Lau, Stephen R.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Numerical Analysis (math.NA)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Mathematics
subject: FOS: Physical sciences

description: Time-domain simulation of wave phenomena on a finite computational domain often requires a fictitious outer boundary. An important practical issue is the specification of appropriate boundary conditions on this boundary, often conditions of complete transparency. Attention to this issue has been paid elsewhere, and here we consider a different, although related, issue: far-field signal recovery. Namely, from smooth data recorded on the outer boundary we wish to recover the far-field signal which would reach arbitrarily large distances. These signals encode information about interior scatterers and often correspond to actual measurements. This article expresses far-field signal recovery in terms of time-domain convolutions, each between a solution multipole moment recorded at the boundary and a sum-of-exponentials kernel. Each exponential corresponds to a pole term in the Laplace transform of the kernel, a finite sum of simple poles. Greengard, Hagstrom, and Jiang have derived the large-$\ell$ (spherical-harmonic index) asymptotic expansion for the pole residues, and their analysis shows that, when expressed in terms of the exact sum-of-exponentials, large-$\ell$ signal recovery is plagued by cancellation errors. Nevertheless, through an alternative integral representation of the kernel and its subsequent approximation by a {\em smaller} number of exponential terms (kernel compression), we are able to alleviate these errors and achieve accurate signal recovery. We empirically examine scaling relations between the parameters which determine a compressed kernel, and perform numerical tests of signal "teleportation" from one radial value $r_1$ to another $r_2$, including the case $r_2=\infty$. We conclude with a brief discussion on application to other hyperbolic equations posed on non-flat geometries where waves undergo backscatter.
description: 19 pages, 11 figures, 1 table, uses svjour3. Version 2 corrects minor typos, including some that appear in the published version
Macroscopic Unobservability of Spinorial Sign Changes
Creators: name: Gill, Richard D.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: In Section 5 of Christian (2014), published in IJTP, an experiment is described which is purported to have the capacity for exhibiting quantum correlations in a completely classical environment. Unfortunately the experiment has an interesting self-destructive property: it is certain not to deliver the required result, hence it is pretty certain that no experimenter will ever bother to perform it.
description: Revised according to request of referee of IJTP: added comments on senselessness of bivectorial correlation in context of Bell's theorem
In vitro schistosomicidal activity of the lignan (−)-6,6′-dinitrohinokinin (DNHK) loaded into poly(lactic-co-glycolic acid) nanoparticles against Schistosoma mansoni
Creators: name: Thaís C. Lima
name: Lucarini, Rodrigo
name: Luz, Priscilla P.
name: De Faria, Emerson H.
name: Liziane Marçal
name: Lizandra G. Magalhães
name: Badoco, Fernanda R.
name: Esperandim, Viviane R.
name: Molina, Eduardo F.
name: Laurentz, Rosangela S.
name: Regiane G. Lima
name: Cunha, Wilson R.
name: Bastos, Jairo K.
name: Silva, Marcio L. Andrade
Publisher: name: Taylor & Francis
Year: 2020
Subjects: subject: Biochemistry
subject: Space Science
subject: Medicine
subject: Biotechnology
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: Science Policy
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences

description: Context: (−)-6,6′-Dinitrohinokinin (DNHK) display remarkable antiparasitic activity and was, therefore, incorporated into a nanoparticle formulation. Objective: Incorporation of DNHK in poly lactic-co-glycolic acid (PLGA) nanoparticles aiming to improve its biological activities. Materials and methods: Synthesis, characterization and incorporation of DNHK into glycolic acid (PLGA) nanoparticles by nanoprecipitation method. The nanoparticles were characterized by ultraviolet-visible spectroscopy, X-ray diffraction, field emission electron microscopic scanning mansoni (FESEM), and dynamic light scattering (DLS). For the in vitro test with Schistosoma mansoni, the DNHK-loaded PLGA was diluted into the medium, and added at concentrations 10–200 µM to the culture medium containing one adult worm pair. The parasites were kept for 120 h and monitored every 24 h to evaluate their general condition, including: pairing, alterations in motor activity and mortality. Results: The loaded PLGA nanoparticles gave an encapsulation efficiency of 42.2% and showed spherical characteristics in monodisperse polymeric matrix. The adult worm pairs were separated after 120 h of incubation for concentrations higher than 50 µM of DNHK-loaded PLGA. The groups incubated with 150 and 200 µM of DNHK-loaded PLGA for 24 and 120 h killed 100% of adult worms, afforded LC50 values of 137.0 ± 2.12 µM and 79.01 ± 1.90 µM, respectively, which was similar to the effect displayed by 10 µM of praziquantel. Discussion and conclusions: The incorporation of DNHK-loaded showed schistosomicidal activity and allowed its sustained release. The loaded PLGA system can be administered intravenously, as well as it may be internalized by endocytosis by the target organisms.
Anti-inflammatory activity of clove (Eugenia caryophyllata) essential oil in human dermal fibroblasts
Creators: name: Xuesheng Han
name: Parker, Tory L.
Publisher: name: Taylor & Francis
Year: 2017
Subjects: subject: Biophysics
subject: Biochemistry
subject: Cell Biology
subject: Genetics
subject: FOS: Biological sciences
subject: Molecular Biology
subject: Physiology
subject: Pharmacology
subject: Biotechnology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Immunology
subject: FOS: Clinical medicine
subject: 69999 Biological Sciences not elsewhere classified
subject: Developmental Biology

description: Context: Clove (Eugenia caryophyllata Thunb. [Myrtaceae]) essential oil (CEO) has been shown to possess antimicrobial, antifungal, antiviral, antioxidant, anti-inflammatory and anticancer properties. However, few studies have focused on its topical use. Objective: We investigated the biological activity of a commercially available CEO in a human skin disease model. Materials and methods: We evaluated the effect of CEO on 17 protein biomarkers that play critical roles in inflammation and tissue remodelling in a validated human dermal fibroblast system, which was designed to model chronic inflammation and fibrosis. Four concentrations of CEO (0.011, 0.0037, 0.0012, and 0.00041%, v/v) were studied. The effect of 0.011% CEO on genome-wide gene expression was also evaluated. Results and discussion: CEO at a concentration of 0.011% showed robust antiproliferative effects on human dermal fibroblasts. It significantly inhibited the increased production of several proinflammatory biomarkers such as vascular cell adhesion molecule-1 (VCAM-1), interferon γ-induced protein 10 (IP-10), interferon-inducible T-cell α chemoattractant (I-TAC), and monokine induced by γ interferon (MIG). CEO also significantly inhibited tissue remodelling protein molecules, namely, collagen-I, collagen-III, macrophage colony-stimulating factor (M-CSF), and tissue inhibitor of metalloproteinase 2 (TIMP-2). Furthermore, it significantly modulated global gene expression and altered signalling pathways critical for inflammation, tissue remodelling, and cancer signalling processes. CEO significantly inhibited VCAM-1 and collagen III at both protein and gene expression levels. Conclusions: This study provides important evidence of CEO-induced anti-inflammatory and tissue remodelling activity in human dermal fibroblasts. This study also supports the anticancer properties of CEO and its major active component eugenol.
Multifrequency spin resonance in diamond
Creators: name: Childress, Lilian
name: McIntyre, Jean
Publisher: name: arXiv
Year: 2010
Subjects: subject: Quantum Physics (quant-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Magnetic resonance techniques provide a powerful tool for controlling spin systems, with applications ranging from quantum information processing to medical imaging. Nevertheless, the behavior of a spin system under strong excitation remains a rich dynamical problem. In this paper, we examine spin resonance of the nitrogen-vacancy center in diamond under conditions outside the regime where the usual rotating wave approximation applies, focusing on effects of multifrequency excitation and excitation with orientation parallel to the spin quantization axis. Strong-field phenomena such as multiphoton transitions and coherent destruction of tunneling are observed in the spectra and analyzed via numerical and analytic theory. In addition to illustrating the response of a spin system to strong multifrequency excitation, these observations may inform techniques for manipulating electron-nuclear spin quantum registers.
Evidence for a First Order, Finite Temperature Phase Transition in 8 Flavor QCD
Creators: name: Jin, Xiao-Yong
name: Mawhinney, Robert D.
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: As part of our ongoing investigations of QCD with many flavors of quarks, here we report on studies of the finite temperature phase transition for eight-flavor QCD with the DBW2 gauge action and naïve staggered fermions. We find a clear first order phase transition between the chirally asymmetric phase at zero temperature and the chirally symmetric phase at finite temperature, signaled by a two-state signal for $\langle\barψψ\rangle$ at a non-zero temperature. We see this signal at a gauge coupling of $β=0.54$, where, to set the scale, the zero temperature value for $f_π$, in the chiral limit, is 0.06661(92). This strong, first-order signal is seen for two different values of the quark mass, $m_q=0.007$ and 0.0195, at $N_τ=8$ and 6 respectively. Using $f_π(m_q)$ as the scale, the critical temperature is measured to be $T_c/f_π=1.638(93)$ at $m_π/f_π=3.329(30)$ for $m_q=0.007$, and $T_c/f_π=1.779(27)$ at $m_π/f_π=4.093(15)$ for $m_q=0.0195$. At a weaker coupling $β=0.56$, where at zero temperature and in the chiral limit we find $f_π=0.0312(10)$, the first order signal becomes numerically invisible to us for the $N_τ\leq 14$ lattices we have investigated so far.
description: 7 pages, 8 figures, 1 table, Talk presented at The XXVIII International Symposium on Lattice Field Theory, LATTICE 2010 - Villasimius, Sardinia Italy / June 14-19, 2010
Mesh Interest Point Detection Based on Geometric Measures and Sparse Refinement
Creators: name: Lin, Xinyu
name: Zhu, Ce
name: Liu, Yipeng
Publisher: name: arXiv
Year: 2016
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Three dimensional (3D) interest point detection plays a fundamental role in 3D computer vision and graphics. In this paper, we introduce a new method for detecting mesh interest points based on geometric measures and sparse refinement (GMSR). The key point of our approach is to calculate the 3D interest point response function using two intuitive and effective geometric properties of the local surface on a 3D mesh model, namely Euclidean distances between the neighborhood vertices to the tangent plane of a vertex and the angles of normal vectors of them. The response function is defined in multi-scale space and can be utilized to effectively distinguish 3D interest points from edges and flat areas. Those points with local maximal 3D interest point response value are selected as the candidates of 3D interest points. Finally, we utilize an $\ell_0$ norm based optimization method to refine the candidates of 3D interest points by constraining its quality and quantity. Numerical experiments demonstrate that our proposed GMSR based 3D interest point detector outperforms current several state-of-the-art methods for different kinds of 3D mesh models.
description: 17 pages
Systematics in the Gamma Ray Bursts Hubble diagram
Creators: name: Cardone, V. F.
name: Perillo, M.
name: Capozziello, S.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Thanks to their enormous energy release which allows to detect them up to very high redshift, Gamma Rays Bursts (GRBs) have recently attracted a lot of interest to probe the Hubble diagram (HD) deep into the matter dominated era and hence complement Type Ia Supernoave (SNeIa). However, lacking a local GRBs sample, calibrating the scaling relations proposed as an equivalent to the Phillips law to standardize GRBs is not an easy task because of the need to estimate the GRBs luminosity distance in a model independent way. We consider here three different calibration methods based on the use of a fiducial $Λ$CDM model, on cosmographic parameters and on the local regression on SNeIa. We find that the calibration coefficients and the intrinsic scatter do not significantly depend on the adopted calibration procedure. We then investigate the evolution of these parameters with the redshift finding no statistically motivated improvement in the likelihood so that the no evolution assumption is actually a well founded working hypothesis. Under this assumption, we then consider possible systematics effects on the HDs introduced by the calibration method, the averaging procedure and the homogeneity of the sample arguing against any significant bias. We nevertheless stress that a larger GRBs sample with smaller uncertainties is needed to definitely conclude that the different systematics considered here have indeed a negligible impact on the HDs thus strengthening the use of GRBs as cosmological tools.
description: 14 pages, 1 figure, 6 tables
Neo-clerodane diterpenoids from Conyza pyrrhopappa Sch.Bip. ex A.Rich
Creators: name: Bitchagno, Gabin Thierry M.
name: Schüffler, Anja
name: Simo, Ingrid K.
name: Krumb, Matthias
name: Tane, Pierre
name: Opatz, Till
Publisher: name: Taylor & Francis
Year: 2019
Subjects: subject: Biochemistry
subject: Cell Biology
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Ecology
subject: FOS: Biological sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: Cancer

description: Two hitherto unknown neo-clerodane-type diterpenoids along with twelve known compounds have been isolated from Conyza pyrrhopappa Sch.Bip. ex A.Rich, a medicinal plant traditionally used across tropical Africa to relieve fever. The structures of isolates have been elucidated by a combination of spectroscopic techniques. The crude extract and the isolated compounds were evaluated in the Hela-S3 cell line and in a panel of microorganisms (bacteria and fungi) at concentrations up to 50 µg/mL. The new compounds were inactive while the pentamethylated flavonoids showed low to significant activity against the cancer cell line used. However, none of the samples showed any activity against the tested microorganisms at this concentration. The present manuscript is the first investigation of the cytotoxicity of phytochemicals and extract from C. pyrrhopappa.
Chemical composition and cytotoxic properties of Clinacanthus nutans root extracts
Creators: name: Peik Lin Teoh
name: Cheng, Angelina Ying Fang
name: Liau, Monica
name: Fui Fui Lem
name: Kaling, Grace P.
name: Chua, Fern Nie
name: Cheong, Bo Eng
Publisher: name: Taylor & Francis
Year: 2016
Subjects: subject: Biochemistry
subject: Molecular Biology
subject: Pharmacology
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Ecology
subject: FOS: Biological sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: Cancer
subject: Inorganic Chemistry
subject: Plant Biology

description: Context:Clinacanthus nutans Lindau (Acanthaceae) is a medicinal plant that has been reported to have anti-inflammatory, antiviral, antimicrobial and antivenom activities. In Malaysia, it has been widely claimed to be effective in various cancer treatments but scientific evidence is lacking. Objective: This study investigates the chemical constituents, anti-proliferative, and apoptotic properties of C. nutans root extracts. Materials and methods: The roots were subjected to solvent extraction using methanol and ethyl acetate. The anti-proliferative effects of root extracts were tested at the concentrations of 10 to 50 μg/mL on MCF-7 and HeLa by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay for 72 h. Morphological changes were observed under light microscope. Pro-apoptotic effects of root extracts were examined using flow cytometric analysis and RT-PCR. The chemical compositions of root extracts were detected using GC-MS. Results: The proliferation of MCF-7 cells was inhibited with the IC50 values of 35 and 30 μg/mL, respectively, for methanol and ethyl acetate root extracts. The average inhibition of HeLa cells was ∼25%. Induction of apoptosis in MCF-7 was supported by chromatin condensation, down-regulation of BCL2 and unaltered expression of BAX. However, only ethyl acetate extract caused the loss of mitochondrial membrane potential. GC-MS analysis revealed the roots extracts were rich with terpenoids and phytosterols. Discussion and conclusions: The results demonstrated that root extracts promote apoptosis by suppressing BCL2 via mitochondria-dependent or independent manner. The identified compounds might work solely or cooperatively in regulating apoptosis. However, further studies are required to address this.
The experience, contributors, and etiology of pain in people with chronic obstructive pulmonary disease
Creators: name: Chen, Yi-Wen
Publisher: name: University of British Columbia
Year: 2018

description: Pain is a common symptom in patients with chronic obstructive pulmonary disease (COPD). This symptom can negatively affect physical activity levels, quality of life, and health outcomes. It has been shown that systemic inflammation, comorbidities, and symptoms (e.g., dyspnea or fatigue) may cause pain. Although previous research has determined the association between pain and the presence of comorbidities, the specific comorbidities that cause pain and other etiologic factors of pain are still unknown. Also, the interrelationships among pain, dyspnea, and fatigue and whether the presence of one symptom accentuates another remain to be examined. The overall purpose of this dissertation was to investigate the etiology of pain by exploring the pain experience, the contributors to pain, the interrelationships between pain and other symptoms, and the associations between pain and thoracic abnormalities in patients with COPD. Studies I and II established the reliability and validity of the Brief Pain Inventory (BPI), Dyspnea Inventory (DI), and Brief Fatigue Inventory (BFI) in patients with COPD. Study III determined comorbidities that caused pain as well as compared pain, fatigue, and dyspnea symptomology in patients with COPD. This study utilized a cross-sectional survey design that included the BPI, DI, BFI, General Self-efficacy Scale, Clinical COPD Questionnaire, and Comorbidities/Medication Questionnaire. Study IV investigated chest computed tomography images of patients with COPD and current/ex-smokers to examine the associations between trunk pain and thoracic vertebral deformity and arthropathy. The findings showed that the BPI, DI, and BFI were reliable and valid questionnaires to evaluate symptoms in COPD. Similar to dyspnea and fatigue, pain was also a significant symptom in patients with COPD and these three symptoms were correlated with each other. Further, the most common comorbidities that caused pain were musculoskeletal diseases. Trunk pain in patients with COPD was associated with thoracic vertebral deformities, arthropathy of thoracic joints, and hyperkyphosis. In summary, pain in COPD is associated with musculoskeletal comorbidities and there are interactions between pain and other symptoms. This dissertation provides insight into the causes of pain in patients with COPD, which can facilitate the development of pain management strategies in COPD.
Soy isoflavones exert beneficial effects on letrozole-induced rat polycystic ovary syndrome (PCOS) model through anti-androgenic mechanism
Creators: name: Rajan, Ravi Kumar
name: Siva Selva Kumar, M.
name: Balaji, Bhaskar
Publisher: name: Taylor & Francis
Year: 2016
Subjects: subject: Biochemistry
subject: Cell Biology
subject: Genetics
subject: FOS: Biological sciences
subject: Physiology
subject: Pharmacology
subject: Biotechnology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: 19999 Mathematical Sciences not elsewhere classified
subject: FOS: Mathematics
subject: Cancer

description: Context: Soy is the main source of phytoestrogens, which has long been used as traditional food. One major subtype of phytoestrogens includes isoflavones and they are scientifically validated for their beneficial actions on many hormone-dependent conditions. Objective: The present study examines the effect of soy isoflavones on letrozole-induced polycystic ovary syndrome (PCOS) rat model. Materials and methods: PCOS was induced in Sprague–Dawley rats with of 1 mg/kg letrozole, p.o. once daily for 21 consecutive days. Soy isoflavones (50 and 100 mg/kg) was administered for 14 days after PCOS induction. Physical parameters (body weight, oestrous cycle determination, ovary and uterus weight) metabolic parameters (oral glucose tolerance test, total cholesterol), steroidal hormone profile (testosterone and 17β-oestradiol), steroidogenic enzymes (3β-hydroxy steroid dehydrogenase (HSD) and 17β-HSD), oxidative stress and histopathology of ovary were studied. Results: Soy isoflavones (100 mg/kg) treatment significantly altered the letrozole-induced PCOS symptoms as observed by decreased body weight gain (p p p p p Discussion: Treatment with soy isoflavones exerts beneficial effects in PCOS rats (with decreased aromatase activity) which might be due to their ability to decrease testosterone concentration in the peripheral blood. Conclusion: Analysis of physical, biochemical and histological evidences shows that soy isoflavones may be beneficial in PCOS.
Two-body problem for two-dimensional electrons in Bernervig-Hughes-Zhang model
Creators: name: Sablikov, Vladimir A.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We study the two-body problem for two-dimensional electron systems in a symmetrized Bernevig-Hughes-Zhang model which is widely used to describe topological and conventional insulators. The main result is that two interacting electrons can form bound states with the energy in the gap of the band spectrum. The pairing mechanism can be interpreted as the formation of a negative reduced effective mass of two electrons. The problem is complicated because the relative motion of the electrons is coupled to the center-of-mass motion. We consider the case of zero total momentum. Detail calculations are carried out for the repulsive interaction potential of steplike form. The states are classified according to their spin structure and two-particle basis functions that form a given bound state. We analyze the spectra and electronic structure of the bound states in the case of both topological and trivial phases and especially focus on effects originating from the band inversion and the coupling of the electron and hole bands. In the trivial phase and the topological phase with the large coupling parameter $a$, the bound state spectra are qualitatively similar. However, when $a$ is less a certain value, the situation changes dramatically. In the topological phase, new states arise with a higher binding energy at lower interaction potential, which evidences that the band inversion can favor pairing the electrons.
description: 17 pages, 15 figures. Small edits
New lupane-type and ursane-type triterpene saponins from the leaves of Trevesia palmata
Creators: name: Yen, Pham Hai
name: Van Doan, Vu
name: Lien, Giang Thi Kim
name: Chuong, Nguyen Thị Hong
name: Thanh, Nguyen Thi Viet
name: Trang, Do Thi
name: Dung, Duong Thi
name: Nhiem, Nguyen Xuan
name: Tai, Bui Huu
name: Van Minh, Chau
name: Van Kiem, Phan
Publisher: name: Taylor & Francis
Year: 2019
Subjects: subject: Biophysics
subject: Biochemistry
subject: Space Science
subject: Microbiology
subject: FOS: Biological sciences
subject: Cell Biology
subject: Pharmacology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Ecology
subject: 69999 Biological Sciences not elsewhere classified
subject: Developmental Biology
subject: 60506 Virology

description: Three new triterpene saponins including two lupane-types and an ursane-type were isolated from the leaves of Trevesia palmata. Their structures were determined as 2α,3β,23-trihydroxylup-20(29)-en-28-oic acid 3-O-α-L-arabinopyranoside (1), 2α,3β,23-trihydroxylup-20(29)-en-28-oic acid 3-O-[α-L-arabinopyranoside]-28-O-[β-D-glucopyranosyl] ester (2), and 2α,3β,23-trihydroxyurs-12-en-28-oic acid 3-O-[α-L-arabinopyranoside]-28-O-[β-D-glucopyranosyl(1→2)-β-D-glucopyranosyl] ester (3) by analysis of their HR-ESI-MS, 1D and 2D NMR spectra. The 2α,3β,23-trioxygenated pentacyclic triterpenes were uncommonly found in the nature. At concentration of 100 µM, compounds 1–3 inhibited NO production in LPS activated BV2 cells with inhibitory rates of 17.4 ± 1.8%, 33.1 ± 1.2%, and 11.7 ± 2.2%, respectively. But, they did not significantly inhibit yeast α-glucosidase activity.
Confinement-Potential Tuning: From Nonlocal to Local Transport
Creators: name: Müller, G.
name: Weiss, Dieter
name: Klitzing, Klaus von
name: Ploog, K.
name: Nickel, H.
name: Schlapp, W.
name: Lösch, R.
Publisher: name: Universität Regensburg
Year: 1992
Subjects: subject: 530 Physik
subject: 73.60.Br
subject: 73.20.Dx
subject: 73.50.Jt

description: We investigate experimentally the influence of the boundary confining potential on edge channel transport in the quantum Hall regime. It is demonstrated that the steepness of the confining potential and therefore the edge channel separation is much more relevant for transport phenomena observed than "bulk" properties such as the electron mean free path. We change the edge potential by brief illumination using a light-emitting diode and study the crossover from nonlocal to local transport.
Collective Response in the Microwave Photoconductivity of Hall Bar Structures
Creators: name: Vasiliadou, E.
name: Müller, G.
name: Heitmann, D.
name: Weiss, Dieter
name: Klitzing, Klaus von
name: Nickel, H.
name: Schlapp, W.
name: Lösch, R.
Publisher: name: Universität Regensburg
Year: 1993
Subjects: subject: 530 Physik
subject: 72.40.+w
subject: 73.40.-c
subject: 71.45.Gm

description: We have investigated the microwave photoconductivity of 100-ìm- and 50-ìm-wide Hall bars fabricated from GaAs/AlxGa1-xAs heterostructures. We found resonant responses at frequencies fres with fres2(B) =fres2(B=0)+fc2, where fc is the cyclotron frequency of the two-dimensional electron gas in the perpendicularly applied magnetic field B. This shows that the photoresponse is dominated by collective plasmon excitations confined within the width of the Hall structure.
Density results for continuous frames
Creators: name: Mitkovski, Mishko
name: Ramirez, Aaron
Publisher: name: arXiv
Year: 2017
Subjects: subject: Functional Analysis (math.FA)
subject: FOS: Mathematics

description: We derive necessary conditions for localization of continuous frames in terms of generalized Beurling densities. As an important application we provide necessary density conditions for sampling and interpolation in a very large class of reproducing kernel Hilbert spaces.
Density of States in Landau Level Tails of GaAs-AlxGa1-xAs Heterostructures
Creators: name: Weiss, Dieter
name: Stahl, E.
name: Weimann, G.
name: Ploog, K.
name: Klitzing, Klaus von
Publisher: name: Universität Regensburg
Year: 1986
Subjects: subject: 530 Physik

description: From an analysis of the thermally activated resistivity as a function of the magnetic field in the quantum Hall regime we deduced the position of the Fermi energy in the mobility gap as a function of the filling factor and therefore the density of states. The measured density of states is best described by a Gaussian like profile superimposed on a constant background.
The physical properties of the dust in the RCW 120 HII region as seen by Herschel
Creators: name: Anderson, L. D.
name: Zavagno, A.
name: Rodon, J. A.
name: Russeil, D.
name: Abergel, A.
name: Ade, P.
name: Andre, P.
name: Arab, H.
name: Baluteau, J. -P.
name: Bernard, J. -P.
name: Blagrave, K.
name: Boulanger, F.
name: Cohen, M.
name: Compiegne, M.
name: Cox, P.
name: Dartois, E.
name: Davis, G.
name: Emery, R.
name: Fulton, T.
name: Gry, C.
name: Habart, E.
name: Huang, M.
name: Joblin, C.
name: Jones, S. C.
name: Kirk, J.
name: Lagache, G.
name: Lim, T.
name: Madden, S.
name: Makiwa, G.
name: Martin, P.
name: Miville-Deschenes, M. -A.
name: Molinari, S.
name: Moseley, H.
name: Motte, F.
name: Naylor, D. A.
name: Okumura, K.
name: Gocalvez, D. Pinheiro
name: Polehampton, E.
name: Saraceno, P.
name: Sidher, S.
name: Spencer, L.
name: Swinyard, B.
name: Ward-Thompson, D.
name: White, G. J.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Context. RCW 120 is a well-studied, nearby Galactic HII region with ongoing star formation in its surroundings. Previous work has shown that it displays a bubble morphology at mid-infrared wavelengths and has a massive layer of collected neutral material seen at sub-mm wavelengths. Given the well-defined photo-dissociation region (PDR) boundary and collected layer, it is an excellent laboratory to study the "collect and collapse" process of triggered star formation. Using Herschel Space Observatory data at 100, 160, 250, 350, and 500 micron, in combination with Spitzer and APEX-LABOCA data, we can for the first time map the entire spectral energy distribution of an HII region at high angular resolution. Aims. We seek a better understanding of RCW120 and its local environment by analysing its dust temperature distribution. Additionally, we wish to understand how the dust emissivity index, beta, is related to the dust temperature. Methods. We determine dust temperatures in selected regions of the RCW 120 field by fitting their spectral energy distribution (SED), derived using aperture photometry. Additionally, we fit the SED extracted from a grid of positions to create a temperature map. Results. We find a gradient in dust temperature, ranging from >30 K in the interior of RCW 120, to ~20K for the material collected in the PDR, to ~10K toward local infrared dark clouds and cold filaments. Our results suggest that RCW 120 is in the process of destroying the PDR delineating its bubble morphology. The leaked radiation from its interior may influence the creation of the next generation of stars. We find support for an anti-correlation between the fitted temperature and beta, in rough agreement with what has been found previously. The extended wavelength coverage of the Herschel data greatly increases the reliability of this result.
description: Accepted to A&A as part of the Herschel special issue
Synthesis, molecular modelling studies of indolyl chalcone derivatives and their antimalarial activity evaluation
Creators: name: Jyoti
name: Gaur, Rashmi
name: Kumar, Yogesh
name: Cheema, Harveer Singh
name: Kapkoti, Deepak Singh
name: Darokar, Mahendra P.
name: Khan, Feroz
name: Bhakuni, Rajendra Singh
Publisher: name: Taylor & Francis
Year: 2019
Subjects: subject: Biochemistry
subject: 29999 Physical Sciences not elsewhere classified
subject: FOS: Physical sciences
subject: Medicine
subject: Cell Biology
subject: Pharmacology
subject: Biotechnology
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Science Policy
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences
subject: Computational Biology

description: Twenty one chalcone derivatives were synthesized using Claisen-Schmidt condensation, their antimalarial activity against Plasmodium falciparum was determined and quantitative structure–activity relationship (QSAR) was developed. Condensation of substituted acetophenones with various aromatic aldehydes at room temperature gave chalcones in 75–96% yield. Chalcones are secondary metabolites of terrestrial plants, precursors for the biosynthesis of flavonoids and exhibit various biological activities. Antiplasmodial IC50 (half-maximal inhibitory concentration) activity of a compound against malaria parasites in vitro provides a good first screen for identifying the antimalarial potential of the compound. The most active compound was Trans-3-(1H-indol-3-yl)-1-(2’-hydroxyphenyl)-2-propen-1-one (1b) with IC50 of 2.1 µM/L. Molecular mechanism was explored through in silico docking & ADMET studies for the active compounds.
On anti-Kekulé and $s$-restricted matching preclusion problems
Creators: name: Lü, Huazhong
name: Li, Xianyue
name: Zhang, Heping
Publisher: name: arXiv
Year: 2017
Subjects: subject: Combinatorics (math.CO)
subject: Discrete Mathematics (cs.DM)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences
subject: 05C72, 05C92, 68R10

description: The anti-Kekulé number of a connected graph $G$ is the smallest number of edges whose deletion results in a connected subgraph having no Kekulé structures (perfect matchings). As a common generalization of (conditional) matching preclusion number and anti-Kekulé number of a graph $G$, we introduce $s$-restricted matching preclusion number of $G$ as the smallest number of edges whose deletion results in a subgraph without perfect matchings such that each component has at least $s+1$ vertices. In this paper, we first show that conditional matching preclusion problem and anti-Kekulé problem are NP-complete, respectively, then generalize this result to $s$-restricted matching preclusion problem. Moreover, we give some sufficient conditions to compute $s$-restricted matching preclusion numbers of regular graphs. As applications, $s$-restricted matching preclusion numbers of complete graphs, hypercubes and hyper Petersen networks are determined.
description: 17 pages, 2 figures
Transport Phenomena of Inversion Layers in High Magnetic Fields
Creators: name: Haug, R.
name: Klitzing, Klaus von
name: Weiss, Dieter
Publisher: name: Universität Regensburg
Year: 1986
Subjects: subject: 530 Physik
subject: 73.40.-c
subject: 01.30.Rr
subject: 07.55.Db
subject: 73.43.-f
subject: 72.10.-d

description: The discovery of the quantum Hall effect in 1980 has demonstrated the importance of two- dimensional electronic systems for application and fundamental research. In this paper a review of some transport phenomena in such systems in high magnetic fields is given.
Near-zone sizes and the rest frame extreme ultra-violet spectral index of the highest redshift quasars
Creators: name: Wyithe, Stuart
name: Bolton, James S.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: The discovery of quasars with redshifts higher than six has prompted a great deal of discussion in the literature regarding the role of quasars, both as sources of reionization, and as probes of the ionization state of the IGM. However the extreme ultra-violet (EUV) spectral index cannot be measured directly for high redshift quasars owing to absorption at frequencies above the Lyman limit, and as a result, studies of the impact of quasars on the intergalactic medium during reionization must assume a spectral energy distribution in the extreme ultra-violet based on observations at low redshift, z<1. In this paper we use regions of high Ly-alpha transmission (near-zones) around the highest redshift quasars to measure the quasar EUV spectral index at z~6. We jointly fit the available observations for variation of near-zone size with both redshift and luminosity, and propose that the observed relation provides evidence for an EUV spectral index that varies with absolute magnitude in the high redshift quasar sample, becoming softer at higher luminosity. Using a large suite of detailed numerical simulations we find that the typical value of spectral index for a luminous quasar at z~6 is constrained to be alpha=1.3+/-0.4 for a specific luminosity of the form L\proptoν^{-alpha}. We find the scatter in spectral index among individual quasars to be in the range ~0.75-1.25. These values are in agreement with direct observations at low redshift, and indicate that there has been no significant evolution in the EUV spectral index of quasars over 90% of cosmic time.
description: 12 pages, 8 figures. Submitted to MNRAS
Quantum deformation of quantum cosmology: A framework to discuss the cosmological constant problem
Creators: name: Jalalzadeh, S.
name: Capistrano, A. J. S.
name: Moniz, P. V.
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We endorse the context that the cosmological constant problem is a quantum cosmology issue. Therefore, in this paper we investigate the $q$-deformed Wheeler-DeWitt equation of a spatially closed homogeneous and isotropic Universe in the presence of a conformally coupled scalar field. Specifically, the quantum deformed Universe is a quantized minisuperspace model constructed from quantum Heisenberg-Weyl $\mathcal U_q(h_4)$ and $\mathcal U_q(su(1, 1))$ groups. These intrinsic mathematical features allow to establish that ($i$) the scale factor, the scalar field and corresponding momenta are quantized and ($ii$) the phase space has a non-equidistance lattice structure. On the other hand, such quantum group structure provides us a new framework to discuss the cosmological constant problem. Subsequently, we show that a ultraviolet cutoff can be obtained at $10^{-3} eV$, i.e., at a scale much larger than the expected Planck scale. In addition, an infrared cutoff, at the size of the observed Universe, emerges from within such quantum deformation of Universe. In other words, the spectrum of the scale factor is upper bounded. Moreover, we show that the emerged cosmological horizon is a quantum sphere $S^2_q$ or, alternatively, a fuzzy sphere $S^2_F$ which explicitly exhibits features of the holographic principle. The corresponding number of fundamental cells equals the dimension of the Hilbert space and hence, the cosmological constant can be presented as a consequence of the quantum deformation of the FLRW minisuperspace.
description: 14 pages, to appear in Physics of Dark Universe
Kondo screening regimes of a quantum dot with a single Mn ion
Creators: name: vernek, E.
name: Qu, Fanyao
name: Souza, F. M.
name: Egues, J. C.
name: Anda, E. V.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We study the Kondo and transport properties of a quantum dot with a single magnetic Mn ion connected to metallic leads. By employing a numerical renormalization group technique we show that depending on the value of ferromagnetic coupling strength between the local electronic spin and the magnetic moment of the Mn, two distinct Kondo regimes exist. In the weak coupling limit, the system can be found in a completely screened Kondo state describing a local magnetic moment decoupled from the rest of the system. In contrast, in the strong coupling regime the quantum dot spin and the local magnetic moment form a single large-spin entity partially Kondo screened. A crossover between these two regimes can be suitably tuned by varying the tunnel coupling between the quantum dot electron and the leads. The model investigated here is also suitable to study magnetic molecules adsorbed on a metallic surface. The rich phenomenology of these systems is reflected in the conductance across the system.
description: 5 pages, 4 figures