bluuebunny/crossref_metadata_2025 huggingface dataset:
Harnessing the Population Statistics of Subhalos to Search for Annihilating Dark Matter
Authors: Somalwar Jean J. , Chang Laura J. , Mishra-Sharma Siddharth , Lisanti Mariangela
Published: January 2021

The Milky Way’s dark matter halo is expected to host numerous low-mass subhalos with no detectable associated stellar component. Such subhalos are invisible unless their dark matter annihilates to visible states such as photons. One of the established methods for identifying candidate subhalos is to search for individual unassociated gamma-ray sources with properties consistent with the dark matter expectation. However, robustly ruling out an astrophysical origin for any such candidate is challenging. In this work, we present a complementary approach that harnesses information about the entire population of subhalos—such as their spatial and mass distribution in the Galaxy—to search for a signal of annihilating dark matter. Using simulated data, we show that the collective emission from subhalos can imprint itself in a unique way on the statistics of observed photons, even when individual subhalos may be too dim to be resolved on their own. Additionally, we demonstrate that, for the models we consider, the signal can be identified even in the face of unresolved astrophysical point-source emission of extragalactic and Galactic origin. This establishes a new search technique for subhalos that is complementary to established methods, and that could have important ramifications for gamma-ray dark matter searches using observatories such as the Fermi Large Area Telescope and the Cerenkov Telescope Array.
Void Probability Function of Simulated Surveys of High-redshift Lyα Emitters
Authors: Perez Lucia A. , Malhotra Sangeeta , Rhoads James E. , Tilvi Vithal
Published: January 2021

We calculate the void probability function (VPF) in simulations of Lyα emitters (LAEs) across a wide redshift range (z = 3.1, 4.5, 5.7, 6.6). The VPF measures the zero-point correlation function (i.e., places devoid of galaxies) and naturally connects to higher-order correlation functions while being computationally simple to calculate. We explore the Poissonian and systematic errors on the VPF, specify its accuracy as a function of average source density and the volume probed, and provide the appropriate size scales to measure the VPF. At small radii, the accuracy of the VPF is limited by galaxy density, while at large radii, the VPF is limited by the number of independent volumes probed. We also offer guidelines for understanding and quantifying the error in the VPF. We approximate the error in the VPF by using independent subvolumes of the catalogs, after finding that jackknife statistics underestimate the uncertainty. We use the VPF to probe the strength of higher-order correlation functions by measuring and examining the hierarchical scaling between the correlation functions using the count-in-cells method. The negative binomial model (NBM) has been shown to best describe the scaling between the two-point correlation function and the VPF for low-redshift galaxy observations. We further test the fit of the NBM by directly deriving the volume-averaged two-point correlation function from the VPF and vice versa. We find the NBM best describes the

simulated LAEs, with a 1σ deviation from the model in the z = 6.6 catalog. This suggests that LAEs show higher-order clustering terms similar to those of normal low-redshift galaxies.
Energetics of Solar Coronal Bright Points
Authors: Hosseini Rad Somaye , Alipour Nasibe , Safari Hossein
Published: January 2021

The several-million-degree, low-density quiet solar corona requires a total energy-loss flux of about 3 × 105 erg cm−2 s−1. Solar coronal bright points (CBPs) are ubiquitous in the quiet Sun. They may release magnetic energy to heat the solar corona, but their contribution to the energy flux has not been determined yet. We used an automatic identification and tracking method for CBPs, which was developed based on the support vector machine classifier and Zernike moments of extreme ultraviolet (EUV) observations from the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory. We applied a spatial synthesis differential emission measure method and a Vertical-Current Approximation Nonlinear Force-Free Field technique to extract the thermal and magnetic energetics of the CBPs, respectively. By analyzing 7.5 yr (within the solar cycle 24) of AIA observations, we show that the average thermal energy and magnetic free energy of 140,000 CBPs are positively correlated with sunspots. However, the number of CBPs and sunspots are highly anti-correlated. We calculate a total energy-loss flux (sum of the radiative and conductive loss flux) of about (4.84 ± 1.60) × 103 erg cm−2 s−1 for the system of CBPs. Therefore, it is about 1.61% ± 0.53% of the total energy-loss flux of quiet corona. By extending the distribution of the magnetic Poynting flux and energy-loss flux for CBPs to nanoflares, the total magnetic Poynting flux and total energy-loss flux are obtained to be in the range of 1.48 × 105 to 1.57 × 106 and 3.86 × 104 to 2.35 × 105 erg cm−2 s−1, respectively.
Giant X-Ray and Optical Bump in GRBs: Evidence for Fallback Accretion Model
Authors: Zhao Litao , Gao He , Lei WeiHua , Lan Lin , Liu Liangduan
Published: January 2021

The successful operation of dedicated detectors has brought us valuable information for understanding the central engine and the progenitor of gamma-ray bursts (GRBs). For instance, the giant X-ray and optical bumps found in some long-duration GRBs (e.g., GRBs 121027A and 111209A) imply that some extended central engine activities, such as the late X-ray flares, are likely due to the fall-back of progenitor envelope materials. Here we systemically search for long GRBs that consist of a giant X-ray or optical bump from the Swift GRB sample, and eventually we find 19 new possible candidates. The fall-back accretion model could interpret the X-ray and optical bump for all candidates within a reasonable parameter space. Six candidates showing simultaneous bump signatures in both X-ray and optical observations, which could be well fitted at the same time when scaling down the X-ray flux into optical by one order of magnitude, are consistent with the standard F

ν
 ∝ ν
1/3 synchrotron spectrum. The typical fall-back radius is distributed around 1010–1012 cm, which is consistent with the typical radius of a Wolf–Rayet star. The peak fall-back accretion rate is in the range of  ∼10−11–10−4
M
⊙ s−1 at time  ∼102–105 s, which is relatively easy to fulfill as long as the progenitor’s metallicity is not too high. Combined with the sample we found, future studies of the mass supply rate for the progenitors with different mass, metallicity, and angular momentum distribution would help us to better constrain the progenitor properties of long GRBs.
Small-scale Dynamo in Stably Stratified Turbulence
Authors: Skoutnev V. , Squire J. , Bhattacharjee A.
Published: January 2021

We present numerical investigations into three principal properties of a small-scale dynamo in stably stratified turbulence: the onset criterion, the growth rate, and the nature of the magnetic field anisotropy in the kinematic regime. The results suggest that all three dynamo properties are controlled by the scale separation between the Ozmidov scale and the viscous or resistive scale. In addition to the critical magnetic Reynolds number, this allows for the definition of critical buoyancy and magnetic buoyancy Reynolds numbers for stratified small-scale dynamo onset in the high and low magnetic Prandtl number regimes, respectively. The presence of a small-scale dynamo in stellar radiative zones could affect dynamics through the resulting Maxwell stresses or its influence on large-scale dynamo mechanisms in regions of differential rotation. Taking the solar radiative zone as a representative example and applying the onset criterion, we find that the stratification is strong enough to make the small-scale dynamo marginally active in the stably stratified turbulence of the solar tachocline.
Measuring the Metallicity of Early-type Galaxies. I. Composite Region
Authors: Wu Yu-Zhong
Published: January 2021

We present the data of 9739 early-type galaxies (ETGs), cross-matching Galaxy Zoo 1 with our sample selected from the catalog of the Sloan Digital Sky Survey Data Release 7 of MPA-JHU emission-line measurements. We first investigate the divisor between ETGs with and without star formation (SF), and find the best separator of W2–W3 = 2.0 is added. We explore the ETG sample by refusing a variety of ionization sources, and derive 5376 ETGs with SF by utilizing a diagnostic tool of the division line of W2–W3 = 2.0. We measure their metallicities with four abundance calibrators. We find that our composite ETG sample has similar distributions of M
* and star formation rate as star-forming galaxies (SFGs) do, that most of them lie on the “main sequence,” and that our fit is a slightly steeper slope than that derived in Renzini & Peng. Compared with the distributions between different metallicities calibrated by four abundance indicators, we find that the Curti17 method is the most accurate calibrator for composite ETGs among the four abundance indicators. We present a weak positive correlation of SFR and metallicity only when the metallicity is calibrated by the PP04, Curti17, and T04 indicators. The correlation is not consistent with the negative correlation of both parameters in SFGs. We suggest that the weak correlation is due to the dilution effect of gas inflow driven by minor mergers.
Modelling and investigation of amoxicillin chemical interaction with mineral waters containing a significant amount of calcium and magnesium salts
Authors: Dobrova Anna O. , Golovchenko Olga S. , Georgiyants Victoriya A.
Published: January 2021

In recent years, the interaction of drugs with the components of food and drinks has been actively researched to ensure rational therapy. It is particularly important for amoxicillin as an antibiotic group of drugs, considering the issue of resistance. A study of the interaction of amoxicillin with mineral waters, which in significant quantities may contain cations and anions and enter complexation reactions, has not been conducted before. For the study, various chemical and physicochemical methods were used. Also in vitro dissolution test with conditions of simultaneous administration of amoxicillin with mineral waters in a 0.1M HCl was modelled. Results showed that amoxicillin could form multiple complex compounds with magnesium cations in the 0.1 M HCl with different stoichiometry. The study showed that from several investigated mineral waters, presented on the Ukrainian market, the “Karpatska dzherelna” could interact with amoxicillin in the medium of a 0.1 M HCl.
The investigation of antimicrobial and antifungal activity of some Artemisia L. species
Authors: Hrytsyk Roman Andriiovych , Kutsyk Roman Volodymyrovych , Yurchyshyn Oxana Ivanivna , Struk Оxana Аnatolievna , Kireev Igor Vladimirovich , Grytsyk Andrii Romanovych
Published: January 2021

Background: Throughout history pathogenic microorganisms cause infectious diseases. Medicinal herbs play an important role in human life because they are used for the therapy and production of herbal remedies. Therefore, it is relevant to study the antibacterial activity of medicinal herbs includingArtemisiaL. species.

Aim: The purpose of this study was to investigate the antimicrobial and antifungal activity ofArtemisiaL. species extracts and to identify their synergistic antimicrobial effects with erythromycin against skin isolates ofStaphylococcus aureuswith different mechanisms of MLS-resistance.

Materials and methods:Artemisia absinthiumL. herb extracts (AAs-4, AAs-7, AAs-9),Artemisia vulgarisL. herb extracts (AV-4, AV-7, AV-9) andArtemisia abrotanumL. herb extracts (AAr-4, AAr-7, AAr-9) were used in this study (solvents – 40%, 70% and 90% ethyl alcohol respectively).

The determination of antimicrobial activity of extracts was performed using clinical isolates of antibiotic susceptible and antibiotic resistant microorganisms. Bacterial cultures were identified on the basis of the biochemical microtests “STAPHYtest 16”, “ENTEROtest 24”, “NEFERMENTtest 24” taking into account the complex of their morphological and cultural properties in accordance with the recommendations of the 9thedition of “Bergey’s Manual of Systematic Bacteriology”. Yeast-like fungi cultures were identified on the basis of 40 biochemical tests with the help of the VITEK 2 system using the VITEK 2 YST ID card.

The synergism of the antimicrobial activity of extracts with erythromycin was investigated using the clinical isolate ofStaphylococcus aureuswith the non-inductive MLS-resistance mechanism (resistant to erythromycin at minimum bacteriostatic concentration of 125 μg/ml and minimum bactericidal concentration of 250 μg/ml without induction of resistance to clindamycin).

Research results: The evaluation ofArtemisiaL. herb extracts activity was carried out using standard strains of microorganisms which are recommended by the WHO.

The results of the conducted studies indicate thatArtemisiaL. herb extracts are able to reduce the growth of microorganisms. The investigated extracts showed the potent bacteriostatic action against the cocci or rod-shaped microflora. The antimicrobial activity ofArtemisiaL. herb extracts directly depends on the concentration of ethanol as the solvent.Artemisia vulgarisL. herb extracts (solvents – 70% and 90% ethanol) andArtemisia abrotanumL. herb extract (solvent – 90% ethanol) show synergism of antimicrobial activity with erythromycin in relation toStaphylococcus aureuswith efflux mechanism of MLS-resistance. The obtainedArtemisiaL. herb extracts can be used to create antifungal drugs, as well as antimicrobial drugs (against gram-positive and gram-negative bacteria).
Therapeutic guidelines in chronic low back pain
Authors: Taneva Daniela , Kirkova Angelina , Atanasov Petar
Published: January 2021

Chronic low back pain is a heterogeneous group of disorders with recurrent low back pain over 3 months. The high incidence of lumbago is an important phenomenon in our industrial society. Patients with chronic low back pain often receive multidisciplinary treatment. The bio approach, the psycho-approach, and the social approach optimally reduce the risk of chronicity by providing rehabilitation for patients with persistent pain after the initial acute phase. Damage to the structures of the spinal cord and the occurrence of low back pain as a result of evolutionary, social and medical causes disrupt the rhythm of life and cause less or greater disability. Recovery of patients with low back pain is not limited only to influencing the pain syndrome but requires the implementation of programs to eliminate the complaints that this pathology generates in personal, family and socio-professional terms.

This paper aims to familiarize the audience with the medication used, and the programs for active recovery in patients suffering from chronic low back pain.
The synthesis of N-(4-aryl-thiazol-2-yl)-N1-(4,5,6,7-tetrahydro-3H-azepin-2-yl)-hydrazine hydrobromides and the cardioprotective activity of (41-methoxyphenyl-thiazol-2-yl) derivative
Authors: Demchenko Sergii А. , Fedchenkova Yulia А. , Yeromina Hanna О. , Herashenko Inna V. , Berdnyk Olha H. , Demchenko Anatolii M.
Published: January 2021

A novel series of N-(4-aryl-thiazol-2-yl)-N1-(4,5,6,7-tetrahydro-3Н-azepin-2-yl)-hydrazine derivatives were synthesized by interaction of equimolar quantities of substituted α-bromacetophenones with thiosemicarbazide and characterized on the basis of their elemental analyses and spectral data. Study of cardioprotective activity of the all new products in comparison to levocarnitine and its synthetic analogue mildronate were carried out. Thus, specified results indicate, N-[(41-methoxyphenyl)-thiazol-2-yl)]-N1-(4,5,6,7-tetrahydro-3Н-azepin-2-yl)-hydrazine hydrobromide was influenced deceleration of contractive response of smooth muscles to hypoxia 13.2% more effective than levocarnitine and 6.85% more effective than mildronate and were shown pronounced cardioprotective properties. Obtained data justifies further study of N-(4-aryl-thiazol-2-yl)-N1-(4,5,6,7-tetrahydro-3Н-azepin-yl)-hydrazine derivatives as new potential cardioprotective drugs for treatment of various cardiac diseases.
COVID-19 – the challenge to treat a disease and not a positive RT-PCR test
Authors: Moneva-Sakelarieva Maria Georgieva , Kobakova Yozlem Ali , Atanasov Petar Yordanov , Obreshkova Danka Petrova , Ivanova Stefka Achkova , Stankova Evgenia Kirilova
Published: January 2021

The new pandemic disease COVID is quick spread worldwide.The primary method used for diagnosing of COVID-19 is detecting viral nucleic acids. The main problem with RT-PCR test is the false negative results. The negative RT-PCR does not exclude a SARS-CoV-2 infection and this method should not be used as the only diagnostic criteria. The RT-PCR result does not change the complex treatment of the disease. The aim of the current study is to compare the four groups clinical cases of the different parameters: RT-PCR test, rapid test, clinical picture, laboratory tests as hematology, inflammatory markers, coagulation status and chemistry and imaging examinations: Chest X-ray at and Chest CT scan. Complex therapeutic approach has been implemented: antibiotic, inflammatory, anticoagulants, oxygen therapy, hepatoprotectors, antimycotics, fibrinolytics, probiotics, essential oils, vitamins. During the follow-up period, a tendency for significant reduction and resorption of the pulmonary changes on the CT scans has been seen.
Une décennie de recherches empiriques autour des déterminants de l’efficacité des comités d’audit
Authors: Broye Géraldine , Johannes Pauline
Published: January 2021

La dernière décennie a été riche en avancées scientifiques concernant l’efficacité des comités d’audit en termes de gouvernance des entreprises. Dans cet article, nous proposons une synthèse de cette littérature, en présentant les principaux apports et les implications des publications les plus récentes. Nous organisons cette revue autour de quatre thématiques, identifiées au regard des cadres théoriques et des approches méthodologiques mobilisés. Les facteurs d’efficacité du comité s’avèrent complexes et les chercheurs nous permettent de mieux comprendre les implications multiples de la composition du comité d’audit, de son pilotage, ou des interactions avec les autres acteurs du reporting financier. En analysant les principaux résultats de 143 études publiées entre 2007 et 2018, nous mettons l’accent sur les questions de recherche émergentes et nous identifions les opportunités de recherches futures.
La proximité entre le dirigeant et les administrateurs a-t-elle un impact sur le coût des fonds propres ?
Authors: Van Appelghem Cédric , Nguyen Pascal
Published: January 2021

La formation des élites françaises au sein d’un petit nombre de grandes écoles entraîne l’existence d’une certaine proximité entre dirigeants et administrateurs fondée sur le partage d’un même diplôme. Dans cet article, nous analysons l’effet de cette proximité sur le coût des fonds propres de l’entreprise. Les résultats montrent que la proximité se traduit par un coût des fonds propres plus élevé en raison d’un risque de comportement opportuniste du dirigeant lié à l’affaiblissement du contrôle disciplinaire du conseil d’administration. Cet effet est amplifié lorsque le dirigeant est fortement enraciné du fait d’une longue période en poste ou d’un cumul de mandat avec la présidence du conseil d’administration. Il est en revanche atténué lorsqu’il existe des mécanismes pouvant compenser une défaillance du conseil d’administration, comme la présence d’un gros actionnaire dans le capital de la firme ou un suivi plus important par les analystes financiers. Dans l’ensemble, notre étude met en avant le coût résultant de l’existence de liens sociaux entre le dirigeant et les administrateurs.
Analysis of the Effect of the Size and Grade of Soft Tissue Sarcoma on Rates of Unplanned Resection, Metastatic Disease, Mortality, and Morbid Re-Resection Over 20 Years
Authors: Gagnet Paul , Nelson Joseph , Wallace Nicholas , McCarthy Caitlin , Robbins Chris , Kessler Jason , Biermann J. Sybil , Siegel Geoffrey
Published: January 2021

Soft tissue sarcomas are rare malignancies that are often presumed to be benign and are resected without the typical preoperative workup, such as imaging or biopsy. These unplanned resections occur in approximately 30% of all cases and frequently require further morbid treatments, resulting in worse oncologic outcomes. A retrospective review was performed of all patients who presented to a tertiary sarcoma center with a diagnosis of sarcoma between 1996 and 2017. In-depth chart reviews were performed for the 2600 patients who were identified, with 836 having a primary diagnosis of soft tissue sarcoma in an upper or lower extremity. Data collected included histologic features, grade, size, resection status, demographic features, referral information, metastatic disease, morbid procedures, and mortality rate. Patients were divided into 2 groups based on whether the tumor size was greater or less than 5 cm. This classification was in keeping with the guideline of referring patients to a tertiary sarcoma center for workup for tumors “larger than a golf ball.” The difference in the rate of unplanned resection for tumors measuring less than 5 cm (41.6%) and those measuring 5 cm or greater (18.8%) was statistically significant (
P
<.001), with smaller tumors more likely to undergo unplanned resection, in keeping with the success of the “golf ball rule.” The rate of metastatic disease for unplanned resection for tumors measuring 5 cm or greater (50.7%) was significantly greater than that for tumors measuring less than 5 cm (19.7%) (
P
<.001). The authors found a great deal of morbidity associated with unplanned resection, regardless of tumor size. Before resection is planned, delineation is required beyond tumor size. [
Orthopedics
. 2021;44(3):166–171.]
Serum and Synovial Biomarkers for the Diagnosis of Implant-Associated Infection After Orthopedic Surgery
Authors: Liu Xiaonan , Jiang Nan , Wang Tiantian , Yu Bin
Published: January 2021

Implant-associated infection is one of the most devastating complications following orthopedic surgery. Early identification is crucial for treatment. Currently, however, a reliable diagnostic tool is lacking, partly due to disparate bacteria colonies (virulent vs non-virulent), difficulty in distinguishing infection from inflammatory disease, and highly diverse diagnostic thresholds and testing methods. Given the importance of biomarkers in the initial screening for the infection, an extensive effort has been made to develop serum and synovial biomarkers. In this review, the authors summarize the results from the most relevant studies to provide comprehensive information on biomarkers for the diagnosis of implant-associated infection. [
Orthopedics
. 2021;44(2):e158–e166.]
Complete weight enumerator of torsion codes
Authors: Meng Xiangrui , Gao Jian
Published: January 2021

In this paper, we introduce two classes of MacDonald codes over the finite non-chain ring \begin{document}$ \mathbb{F}_p+v\mathbb{F}_p+v^2\mathbb{F}_p $\end{document} and their torsion codes which are linear codes over \begin{document}$ \mathbb{F}_p $\end{document}, where \begin{document}$ p $\end{document} is an odd prime and \begin{document}$ v^3 = v $\end{document}. We give the complete weight enumerator of two classes of torsion codes. As an application, systematic authentication codes are obtained by these torsion codes.
Singularity formation to the nonhomogeneous magneto-micropolar fluid equations
Authors: Zhong Xin
Published: January 2021

We consider the Cauchy problem of nonhomogeneous magneto-micropolar fluid equations with zero density at infinity in the entire space \begin{document}$ \mathbb{R}^2 $\end{document}. We show that for the initial density allowing vacuum, the strong solution exists globally if a weighted density is bounded from above. It should be noted that our blow-up criterion is independent of micro-rotational velocity and magnetic field.
Langevin differential equation in frame of ordinary and Hadamard fractional derivatives under three point boundary conditions
Authors: Adjabi Yassine ,   Department of Mathematics, Faculty of Sciences, University of M'hamed Bougara, Boumerdès, Dynamic Systems Laboratory, Faculty of Mathematics, U.S.T.H.B., Algeria, Samei Mohammad Esmael , Matar Mohammed M. , Alzabut Jehad ,   Department of Mathematics, Faculty of Basic Science, Bu-Ali Sina University, Hamedan, Iran,   Department of Mathematics, Al-Azhar University-Gaza, State of Palestine,   Department of Mathematics and General Sciences, Prince Sultan University, Riyadh, 11586, Saudi Arabia
Published: January 2021

In this paper, we study a type of Langevin differential equations within ordinary and Hadamard fractional derivatives and associated with three point local boundary conditions

   \begin{document}$ \mathcal{D}_{1}^{\alpha} \left( \mathrm{D}^{2} + \lambda^{2}\right) x(t) = f\left( t, x(t), \mathcal{D}_1^{\alpha} \left[ x\right] (t) \right), $\end{document}

$ \mathrm{D}^{2} x\left(1 \right) = x(1) = 0 $, $ x(e) = \beta x(\xi) $, for $ t\in \left(1, e\right) $ and $ \xi \in (1, e] $, where $ 0 < \alpha < 1 $, $ \lambda, \beta > 0 $, $ \mathcal{D}_1^\alpha $ denotes the Hadamard fractional derivative of order $ \alpha $, $ \mathrm{D} $ is the ordinary derivative and $ f:[1, e]\times C([1, e], \mathbb{R})\times C([1, e], \mathbb{R})\rightarrow C([1, e], \mathbb{R}) $ is a continuous function. Systematical analysis of existence, stability and solution's dependence of the addressed problem is conducted throughout the paper. The existence results are proven via the Banach contraction principle and Schaefer fixed point theorem. We apply Ulam's approach to prove the Ulam-Hyers-Rassias and generalized Ulam-Hyers-Rassias stability of solutions for the problem. Furthermore, we investigate the dependence of the solution on the parameters. Some illustrative examples along with graphical representations are presented to demonstrate consistency with our theoretical findings.
Caputo-Fabrizio fractional differential equations with instantaneous impulses
Authors: Abbas Saïd ,   Department of Mathematics, University of Saïda-Dr. Moulay Tahar, P.O. Box 138, EN-Nasr, 20000 Saïda, Algeria, Benchohra Mouffak , Nieto Juan J. ,   Laboratory of Mathematics, Djillali Liabes University of Sidi Bel-Abbès, P.O. Box 89, Sidi Bel-Abbès 22000, Algeria,   Departamento de Estatistica, Análise Matemática e Optimización, Instituto de Matemáticas, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
Published: January 2021

The subjuct of this paper is the existence of solutions for a class of Caputo-Fabrizio fractional differential equations with instantaneous impulses. Our results are based on Schauder's and Monch's fixed point theorems and the technique of the measure of noncompactness. Two illustrative examples are the subject of the last section.
Lyapunov-type inequalities for Hadamard fractional differential equation under Sturm-Liouville boundary conditions
Authors: Wang Youyu ,   Department of Mathematics, Tianjin University of Finance and Economics, Tianjin 300222, P. R. China, Zhang Lu , Zhang Yang
Published: January 2021

In this paper, we establish new Lyapunov-type inequalities for a Hadamard fractional differential equation under Sturm-Liouville boundary conditions. Our conclusions cover many results in the literature.
Immunodepression COVID-19-related as a promoting factor for severe Pseudomonas sepsis in an infant with not respiratory symptoms
Authors: Zenzeri Letizia , Giannattasio Antonietta , Zito Marinosci Geremia , Ponticiello Eduardo , Iodice Margherita Raffaella , Vitullo Maria Erennia , Tipo Vincenzo
Published: January 2021

The outbreak of coronavirus disease 2019 caused by severe acute respiratory syndrome coronavirus 2 is a reason of concern worldwide. While a high proportion of adult patients have been severely ill, requiring intensive care assistance and mechanical ventilation, pediatric patients seem to have a less invasive clinical expression of the disease. Reasons for a milder disease in children compared to that seen in adults are yet to be elucidated. Nonetheless, severe and fatal cases have been reported in children and are expected to continue to increase with the growing community transmission and overall current disease prevalence. We report the first case of an infant with a very mild not-respiratory COVID- 19 infection and a concomitant invasive bacterial sepsis.
Place and health infrastructure in the Gulf Cooperation Council: A systematic scoping review of GIS applications in health
Authors: Alhuwail Dari , AlSharrah Saad , Coffee Neil T , Al-Refaei Faisal H , Daniel Mark
Published: January 2021

The rising burden of non-communicable diseases is taxing health systems globally. Using data science and information systems is necessary to support public health practices. Geographic Information Systems (GIS) are key to inform and help guide public health policies related to place (i.e. location or where one lives) and how it affects health. Despite the increasing use of GIS for public health globally, its applications to health in the Gulf Cooperation Council (GCC) states remains largely unknown. This systematic scoping review aimed to uncover how GIS has been used in the GCC states to understand “place” and “health”. A comprehensive search of the literature was performed in PubMed, Scopus, Science Citation Index Expanded, ScienceDirect, Embase, IEEE Xplore, and ACM Digital Library during June 2020. All journal articles involving the use of GIS for human health applications in the GCC states published in English in peerreviewed scientific journals were considered. After removing duplicates and applying eligibility criteria, qualitative content analysis was performed for 24 of 630 studies. GIS uses in the GCC states were categorized as health access and planning (n=9), health risk analysis (n=8), disease surveillance (n=6) and community health profiling (n=1). The majority of the uncovered evidence in this study focused on the Kingdom of Saudi Arabia. The results of this study indicate a deficiency of published evidence regarding the use of GIS in support of public health in other GCC states. This stands to compromise planning and strategic decision making in health risk analysis, disease surveillance, community health profiling, health services provision and health interventions.
Corchorus olitorius aqueous extract attenuates quorum sensing-regulated virulence factor production and biofilm formation
Authors: Al-Yousef Hanan M. , Alam Perwez , Khanam Zakia , Amina Musarat , Hassan Wafaa H. B.
Published: January 2021

Objective:

To investigate the effect of Corchorus olitorius aqueous fraction (COAF) on quorum sensing (QS)-regulated virulence factors and biofilm formation in Pseudomonas aeruginosa (PAO1).

Methods:

The preliminary screening of the anti-QS effect of COAF was performed by evaluating the anti-pathogenic activity against Chromobacterium violaceum CV026 biosensor strain. Next, the inhibitory effects of COAF on QS-regulated pyocyanin production, proteolytic and elastolytic activities, swarming motility, and biofilm formation were evaluated in PAO1.

Results:

The results showed that the treatment of COAF significantly decreased the biofilm biomass, attenuated virulence factors, and inhibited swarming motility of PAO1 without affecting the growth of the bacteria in a dose-dependent manner. COAF at 2 000 μg/mL significantly decreased Las B elastase activity in PAO1 culture, exopolysaccharide production, swarming motility, pyocyanin level, and biomass of PAO1 by 55% (P<0.05), 60% (P<0.01), 61% (P<0.01), 65%(P<0.01) and 73% (P<0.01), respectively. In addition, the production of violacein was decreased by 62% (P<0.01) with the treatment of a high dose of COAF.

Conclusions:

These findings indicate that COAF can be a potential source of anti-QS agents.
An Overview of the Perspective of Cellular Autophagy
Authors: Alharbi Yasser M. , Bima Abdulhadi I. , Elsamanoudy Ayman Z.
Published: January 2021

Autophagy is a cellular process that eliminates unnecessary cytoplasmic materials, such as long-age proteins, destroyed organelles, and foreign microorganisms. Macroautophagy (MaA), chaperone-mediated autophagy, and microautophagy are the three main types of autophagy. It is regulated by the integration of signaling from the AMPK and mTOR-ULK1 pathways. Autophagy plays a physiological role in health, and its dysregulation could be a pathophysiologic mechanism in different disease conditions. In the current study, we reviewed papers of Google Scholar database, PubMed, PubMed Central, Cochrane Database of Systematic Reviews, MEDLINE, and MedlinePlus with no time limitation and a recent World Health Organization report. In the current review, it could be concluded that autophagy plays many physiological functions, including immune system modulation, and regulates different cellular processes such as metabolism, protein synthesis, and cellular transportation. Dysregulation of autophagy is implicated in tumorigenesis, aging, age-related neurodegeneration, and endothelial dysfunctions. Autophagy dysregulation is also implicated in the newly discovered CoV-COVID-19 pathogenesis.
Aesculus hippocastanum-Derived Extract β-Aescin and In vitro Antibacterial Activity
Authors: Dahash Salma L. , Abass Ourba K. , Abdul-Razaq Myada M. , Al-Kuraishy Hayder M. , Al-Gareeb Ali I.
Published: January 2021

Objectives:

The objective of this study was to investigate the antibacterial activity of β-aescin against common Gram-negative and Gram-positive bacteria.

Materials and Methods:

Agar well diffusion assay was used to determine the antibacterial activity of β-aescin against common Gram-negative and Gram-positive bacteria including Klebsiella pneumoniae, Escherichia coli, Staphylococcus epidermidis, Staphylococcus aureus, and Pseudomonas aeruginosa. Minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of β-aescin were evaluated by serial dilution method.

Results:

β-aescin led to significant antibacterial effects on the tested Gram-negative and Gram-positive bacteria compared to the negative control, P < 0.05 for K. pneumoniae and P. aeruginosa and P < 0.01 for E. coli, S. epidermidis, and S. aureus. On the other hand, β-aescin produced a comparable less antibacterial effect on K. pneumoniae, E. coli, and P. aeruginosa compared to the positive control, P < 0.01, whereas β-aescin illustrated a comparable effect with that of the positive control on Gram-positive S. epidermidis,
P = 0.05. Furthermore, β-aescin illustrated a concentration-dependent antibacterial effect against Gram-positive S. epidermidis and S. aureus compared to the different concentrations, P < 0.01. MIC and MBC of β-aescin were high for Gram-negative bacteria and low for Gram-positive bacteria compared to MIC of the positive control.

Conclusions:

β-aescin is an effective antibacterial herb mainly against Gram-positive S. epidermidis and S. aureus in a concentration-dependent manner.
Scanning Electron Microscopy of Vitellogenic Oocytes and Spawned Eggs of the Portunid Crab Charybdis hellerii (Crustacea-Brachyura) (Milne Edwards, 1867)
Authors: Al-Kandari Shaikha Mohammed , El-Sherif Sohier S. , Hamed Sherifa S.
Published: January 2021

Background:

The portunid crab Charybdis hellerii is an economically critical aquatic species in the Mediterranean region. Several investigators have reported scanning electron microscopy (SEM) observations on some crustacean's eggs' morphology. Going through the previous studies, knowledge regarding the morphology of C. hellerii. vitellogenic oocytes and spawned egg membranes are not available.

Aims and Objectives:

In the present study, an attempt has been made to describe the morphology and the structure of the membranes of vitellogenic oocytes and the newly spawned eggs to provide necessary information for further studies on the reproductive and evolutionary biology of the crab C. hellerii.

Materials and Methods:

Samples of ripe pinkish orange ovaries of non-ovigarous females and the spawned incubated eggs of ovigerous females with orange and grey spawns were processed for scanning electron microscopy. The prepared samples were examined in a Zeiss DSM 940 scanning electron microscope.

Results:

The present SEM study revealed that, vitellogenic oocytes are highly packed with yolk inclusions, which appear to be embedded in a definite acellular matrix and surrounded by a distinct chorion, which is pierced by several pores. The follicle cells appear polygonal in shape and interconnected through thin lateral projections and strongly associated with vitellogenic oocytes. The brooded fertilized eggs are attached through a marked stalk (funiculus) and surrounded by three distinct envelopes, which showed specific ornamentations and variations in their surface topography. The outer envelope coarsely wrinkled, while the middle envelope showed finely wrinkled ornamentation, and the inner envelope appeared with its characteristic spongy, porous appearance.

Conclusions:

This study denotes a significant difference between mature vitellogenic oocytes inside the ripe ovary and the spawned ova. The differences have been shown in the structure and external ornamentation of their surrounding membranes. Unlike the vitellogenic oocytes, the spawned ova were surrounded by three distinct layers, which are differ in their surface architecture. Such membrane architecture is species specific characteristic and has been thought to be an adaptive feature for brooded fertilized eggs to survive from stressful environmental conditions.
Completely displaced pediatric radial neck fracture treated by a combination of Métaizeau method and percutaneous reduction with the blunt-end of a k-wire: a case report and review of literature
Authors: Ikram Mohammad A. , Ahmad Abdul R. , Sani Fazrina A. , Premdas Velummylum B.
Published: January 2021

Management of a completely displaced radial neck fracture is always challenging. A closed method is preferred as higher morbidity is reported in the literature pertaining to open reduction. Métaizeau’s method with retrograde intramedullary pinning of the radius is a popular closed method and the current treatment of choice. In cases, where closed reduction is not achievable, the combination of percutaneous manipulation of the displaced radial head increases closed reduction probabilities. We are presenting two cases of a completely displaced fracture of the radial neck treated by a combination of the Métaizeau method and percutaneous push method using a blunt end of the K-wire, which provided anatomical reduction. Our results confirmed that the supplementation of the percutaneous maneuver is a good option when the Métaizeau method alone cannot achieve satisfactory reduction.
Cytomorphological Patterns of Nerve Aspirates in Pure Neuritic Leprosy—A Single Centre Cross-Sectional Observational Study
Authors: Sandhu Sunmeet , Raman Deep K. , Sood Aradhana , Sinha Preema , Singh Prince Y. , Dixit Prashant K.
Published: January 2021

Background:

Pure neuritic leprosy (PNL) poses a diagnostic challenge because of absence of skin patches, inconclusive skin biopsies and nerve conduction studies. Nerve biopsy though the diagnostic gold standard, is invasive, requires expertise, and may not be feasible in all cases. Fine needle aspiration cytology (FNAC) of accessible thickened nerves can be utilized as a minimally invasive diagnostic modality in PNL. This study was carried out to describe cytomorphological patterns of nerve aspirates in patients of PNL for diagnosis and classification of leprosy and study its advantage, if any, over skin biopsy.

Methods:

Twenty-seven treatment naive clinically diagnosed patients of PNL were included in this cross-sectional study carried out from January 2017 to December 2018 at a tertiary care centre in Western India. FNAC was done from a clinically involved nerve and aspirates were evaluated for cytomorphological characteristics and the presence of Acid-Fast Lepra bacilli.

Results:

Nerve aspirates were diagnostic in 10 (37%) patients while 17 (63%) aspirates showed non-specific or no inflammation. Of the diagnostic aspirates, six (22.2%) were classified as tuberculoid leprosy, three (11.1%) as lepromatous and one (3.7%) as borderline leprosy. Mycobacterium leprae were demonstrated among three (11.1%) of these aspirates. In comparison, only three (11.1%) skin biopsies were diagnostic of leprosy with features of indeterminate spectrum. Remaining 24 skin biopsies showed normal histology in 20 (74.1%) cases to perivascular lymphocytic infiltrate in four (14.8%) cases.

Conclusion:

Our study demonstrates that FNAC of clinically thickened nerves has a better diagnostic yield than skin biopsy in PNL and shows all spectrums of leprosy. It also offers the advantage of sampling major nerve trunks without the fear of residual neurological deficit. However, most of the smears were paucicellular and a negative aspirate does not rule out leprosy.
Non-Small Cell Carcinoma-Not Otherwise Specified on Cytology Specimens in Patients with Solitary Pulmonary Lesion
Authors: Lee Hyoun Wook , Ha Seung Yeon , Roh Mee Sook
Published: January 2021

Context:

Subtyping of solitary pulmonary lesion (SPL) in small amount of cytology specimen using a limited panel of immunohistochemistry (IHC) markers is very important to the correct choice of treatment. This study was performed to categorize non-small cell carcinoma-not otherwise specified (NSCC-NOS) on cytology in patients with SPL, especially with regard to the incidence of metastatic cancer.

Materials and Methods:

We reviewed 91 cases, in which a precise morphology-based, lineage-specific IHC-aided subtyping was not possible, that qualified as NSCC-NOS on cytology. A stepwise clinical approach and IHC of organ-specific markers was performed on each cell block (CB) to exclude metastasis from extrapulmonary malignancies.

Results:

Of the 91 evaluated cases, 65 (71.4%) were diagnosed as non-small cell lung carcinoma (NSCLC)-NOS, 24 (26.4%) were metastatic cancer, and the remaining 2 (2.2%) had undetermined diagnoses. The most frequent primary tumor site was the colorectum (41.7%), followed by breast (20.8%), kidney (8.3%), and then stomach, duodenum, liver, pancreas, gallbladder, prostate, and skin (4.2% each, 1 of 24). Moreover, we found that 7 of the 24 patients with metastatic cancer had a history of extrapulmonary malignancy that was unknown at the time of cytology-based diagnosis.

Conclusions:

These results underscored the need for accurate and stepwise clinical correlation to rule out the possibility of pulmonary metastasis from other sites and appropriate but judicious IHC (i.e., CDX2) on CB for SPL to increase refinement of the cytology diagnosis of NSCC-NOS.
Knowledge, attitude, and practices of health-care providers toward antibiotic prescribing, antibiotic resistance, and multidrug-resistant tuberculosis
Authors: Malhotra Ashna , Kumar Vimal , Juyal Deepak , Gautam Deepak , Malhotra Rajesh
Published: January 2021

Introduction:

Antibiotic resistance (ABR) is a growing public health problem and is a subject of international concern. It poses a serious threat to health and health-care systems in both developed and developing countries. The problem is more confounding with tuberculosis (TB), and drug resistance in TB has threatened the progress made in TB care and control worldwide. The aim of this study was to understand the knowledge, attitude, and practices of health-care providers (HCPs) toward antibiotics, antibiotic prescribing, ABR, and multidrug-resistant TB (MDR-TB).

Materials and Methods:

A total of 125 participants were included in this cross-sectional, questionnaire-based survey conducted in tertiary care teaching hospitals of the Delhi-NCR region. A five-point Likert scale, whose responses ranged from “strongly agree” to “do not know,” was used to record the responses from participants.

Results:

Among the 125 HCPs who participated in the survey, the response rate was 100%. Around 94.4% of the respondents agreed that ABR is an important and a serious public health issue. More than 80% of the respondents strongly agreed that over-the-counter sale and/or dispensing antibiotics without prescription should be controlled. About 86.4% of the participants agreed that MDR-TB is a growing problem and 59.2% strongly agreed that indiscriminate use of anti-TB drugs could be a major causative factor. Almost 85.6% of the participants agreed that a proper diagnosis should be ensured before treating the TB cases.

Conclusions:

HCPs had a good knowledge of antibiotics and the association of its misuse or overuse with increasing ABR. Educational and persuasive measures are certainly needed, but the use of restrictive and organizational measures appears mandatory if the misuse of antibiotics is to be decreased in the near future. A stringent assessment of the impact of implemented measures seems essential to better guide antibiotic stewardship in our country.
A retrospective cross-sectional descriptive study to critically appraise the quality of reporting of health economic evaluations conducted in the Indian setting
Authors: Gupta Sandeep Kumar , Tiwari Ravi Kant , Goel Raj Kumar
Published: January 2021

Background:

The reporting quality of economic research could benefit from enhanced quality assurance procedures. At present, there are small numbers of health economic researches being conducted with Indian context or setting. There is not much clarity about the reporting quality of health economic researches being conducted with Indian context or setting.

Objective:

The primary objective is to of this study was to appraise the quality of reporting of health economic evaluations conducted in the Indian setting and published between January 2014 and December 2018.

Materials and Methods:

This was a retrospective, cross-sectional, descriptive analysis. The MEDLINE in PubMed, Google Scholar, and Science Direct were systematically searched to search for economic evaluations. The consolidated health economic evaluation reporting standards statement checklist was utilized to assess the quality of reporting of the included studies. For grading the quality of the included health economic assessments, the Quality of Health Evaluation Studies (QHES) instrument was used.

Results:

Thirty studies fulfilled the inclusion criteria and were included in the study. The mean QHES score was 80.26 (standard deviation = 8.06). Twenty-five (83.33%, 95% confidence interval [CI]: 0.66–0.92) of the article mentioned perspective of the study. Twenty-nine (96.66%, 95% CI: 0.83–0.99) of the article described the effects of uncertainty for all input parameters. Twenty (66.66%, 95% CI: 0.48–0.80) of the article reported all funding sources.

Conclusions:

Overall, the quality of reporting of the included health economic studies was good, which reemphasizes their usefulness in supporting the decision-making procedure about better medicine. The finding of this study will be a small step toward ensuring robust and high-quality health economics data in India.