bluuebunny/crossref_metadata_2025 huggingface dataset:
Retrograde signaling mediates an adaptive survival response to endoplasmic reticulum stress in Saccharomyces cerevisiae
Authors: Hijazi Imadeddin , Knupp Jeffrey , Chang Amy
Published: January 2020

One major cause of endoplasmic reticulum (ER) stress is homeostatic imbalance between biosynthetic protein folding and protein folding capacity. Cells utilize mechanisms such as the unfolded protein response (UPR) to cope with ER stress. Nevertheless, when ER stress is prolonged or severe, cell death may occur, accompanied by production of mitochondrial reactive oxygen species (ROS). Using a yeast model (Saccharomyces cerevisiae), we describe an innate, adaptive response to ER stress to increase select mitochondrial proteins, O2 consumption and cell survival. The mitochondrial response allows cells to resist additional ER stress. The ER stress-induced mitochondrial response is mediated by activation of retrograde (RTG) signaling to enhance anapleurotic reactions of the tricarboxylic acid cycle. Mitochondrial response to ER stress is accompanied by inactivation of the conserved TORC1 pathway, and activation of Snf1/AMPK, the conserved energy sensor and regulator of metabolism. Our results provide new insight into the role of respiration in cell survival in the face of ER stress, and should help in developing therapeutic strategies to limit cell death in disorders linked to ER stress.

This article has an associated First Person interview with the first author of the paper.
Online Privacy and Information Disclosure by Consumers
Authors: Ichihashi Shota
Published: January 2020

I study the welfare and price implications of consumer privacy. A consumer discloses information to a multiproduct seller, which learns about his preferences, sets prices, and makes product recommendations. Although the consumer benefits from accurate recommendations, the seller may use the information to price discriminate. I show that the seller prefers to commit to not use information for pricing in order to encourage information disclosure. However, this commitment hurts the consumer, who could be better off by precommitting to withhold some information. In contrast to single-product models, total surplus may be lower if the seller can base prices on information. (JEL D11, D83, L81, M31)
Teacher Value Added in a Low-Income Country
Authors: Bau Natalie , Das Jishnu
Published: January 2020

Using data from Pakistan, we show that existing methods produce unbiased and reliable estimates of teacher value added (TVA) despite significant differences in context. Although effective teachers increase learning substantially, observed teacher characteristics account for less than 5 percent of the variation in TVA. The first two years of tenure and content knowledge correlate with TVA in our sample. Wages for public sector teachers do not correlate with TVA, although they do in the private sector. Finally, teachers newly entering on temporary contracts with 35 percent lower wages have similar distributions of TVA to the permanent teaching workforce. (JEL I21, J31, J41, J45, O15)
Learning Job Skills from Colleagues at Work: Evidence from a Field Experiment Using Teacher Performance Data
Authors: Papay John P. , Taylor Eric S. , Tyler John H. , Laski Mary E.
Published: January 2020

We study a program designed to encourage learning from coworkers among school teachers. In an experiment, we document gains in job performance when high- and low-skilled teachers are paired and asked to work together on improving their skills. Pairs are matched on specific skills measured in prior evaluations. Each pair includes a target teacher who scores low in one or more of 19 skills and a partner who scores high in (many of) the target’s deficient skills. Student achievement improved 0.12 standard deviations in low-skilled teachers’ classrooms. Improvements are likely the result of target teachers learning skills from their partner. (JEL I21, J24, J45, M53)
Estado, habitação e o direito à cidade no Brasil: um olhar a partir da colonização do mundo da vida
Authors: Bettine Marco , Meyer Guilherme da Costa
Published: January 2020

O objetivo desse artigo é compreender e apresentar os conteúdos da urbanização contemporânea, explicitando a desigualdade e as contradições que fundamentam a produção do urbano. Parte-se da categoria sistemas e mundo da vida habermasianos para apontar as contradições da cidade. Abordaremos o debate em torno da valorização do espaço e a necessidade de compreensão crítica da renda da terra urbana. Assim, o espaço é entendido não mais apenas como matéria-prima e meio de produção, mas como produto possuidor de valor e que se valoriza segundo dinâmicas propriamente urbanas, espaciais e financeiras, marcando uma fragmentação maior do espaço e instituindo novos mecanismos de espoliação. Também resgataremos, brevemente, o debate em torno das categorias de justiça espacial e direito à cidade.
Estigmas de gênero nos corpos do Hospital Juquery
Authors: Cada Cardoso Camilie
Published: January 2020

Se o Estado detém o monopólio da violência, seria apenas uma consequência se as autoridades médicas também exercessem essa influ sobre os internos de estabelecimentos psiquiátricos públicos. Inaugurado em São Paulo no ano de 1898, o Hospital Juquery se tornou um importante aparato de controle social, função exercida por meio da patologização da loucura e da imposição de padrões de normalidade. Nesse artigo, voltaremos o olhar para as construções de estigmas de gênero na instituição, reconhecendo o impacto da lógica normativista nas experiências vividas dos internos.
A violência como o mito fundador de Moçambique
Authors: Cuco Arcénio Francisco , Muibo Pascoal
Published: January 2020

A história contemporânea de Moçambique confunde-se com violência. Neste texto procuramos analisar essa violência que tem sido o denominador comum no país. O nosso objetivo é tentar traçar uma ideia de uma democracia que, nos parece, pode dar certo para Moçambique e quiçá reduzir os níveis de violência que caracterizam o país. Nisso, partimos de análise bibliográfica e da observação do nosso dia a dia da política no país. Buscamos defender a ideia de que, embora a construção do ideário de paz, a partir do AGP de 1992, seja anterior a constituição das instituições democráticas, é o fortalecimento das instituições democráticas e seu reconhecimento pelos partidos políticos que pode garantir a manutenção dessa paz.
The Pareto Comparisons of a Group of Exponential Discounters
Authors: Chambers Christopher P. , Echenique Federico
Published: January 2020

Agents with different discount factors disagree about some intertemporal trade-offs, but they will also agree sometimes. We seek to understand precisely the nature of their agreements and disagreements. A group of agents is identified with a set of discount factors. We characterize the comparisons that a given interval of discount factors will agree on, including what all discount factors in the interval [0, 1] will agree on. Our result is analogous to how all risk-averse and monotone agents agree on mean-preserving spreads. Motivated by a maxmin representation, we also characterize the comparisons that are consistent with some set of discount factors, when the set is not known or exogenously given. In other words, we describe the Pareto comparisons that are consistent with a society, or group, of exponentially discounting agents.
Data-Driven Management of Post-transplant Medications: An Ambiguous Partially Observable Markov Decision Process Approach
Authors: Boloori Alireza , Saghafian Soroush , Chakkera Harini A. , Cook Curtiss B.
Published: January 2020

Problem definition: Organ-transplanted patients typically receive high amounts of immunosuppressive drugs (e.g., tacrolimus) as a mechanism to reduce their risk of organ rejection. However, because of the diabetogenic effect of these drugs, this practice exposes them to a greater risk of new-onset diabetes after transplantation (NODAT), and hence, becoming insulin dependent. We study and develop effective medication management strategies to address the common conundrum of balancing the risk of organ rejection versus that of NODAT. Academic/practical relevance: Our research contributes to the healthcare operations management literature by developing a robust stochastic decision-making framework that allows for incorporating (1) false-positive and false-negative errors of medical tests, (2) inevitable estimation errors when data sets are used, (3) variability among physician’ attitudes toward ambiguous outcomes, and (4) dynamic and patient risk-profile-dependent progression of health conditions. Methodology: We apply an ambiguous partially observable Markov decision process (APOMDP) approach where dynamic optimization with respect to a “cloud” of possible models allows us to make decisions that are robust to potential misspecifications of risks. Results: We first provide various structural results that facilitate characterizing the optimal medication policies. Utilizing a clinical data set, we then compare the performance of the optimal medication policies obtained from our APOMDP model with the policies currently used in the medical practice. We observe that, in one year after transplant, our proposed policies can improve the life expectancy of each patient up to 4.58%, while reducing the medical expenditures up to 11.57%. Managerial implications: Balancing the risks of organ rejection and diabetes complications and considering factors such as physicians’ attitudes toward ambiguous outcomes, partial observability of medical tests, and patient-specific risk factors are shown to result in more cost-effective strategies for management of post-transplant medications compared with the current medical practice. Finally, simultaneous management of medications can facilitate the care coordination process between transplantation/nephrology and endocrinology departments of a hospital that are typically in charge of administering such medications.
Automation, Research Technology, and Researchers’ Trajectories: Evidence from Computer Science and Electrical Engineering
Authors: Furman Jeffrey L. , Teodoridis Florenta
Published: January 2020

We examine how the introduction of a technology that automates research tasks influences the rate and type of researchers’ knowledge production. To do this, we leverage the unanticipated arrival of an automating motion-sensing research technology that occurred as a consequence of the introduction and subsequent hacking of the Microsoft Kinect system. To estimate whether this technology induces changes in the type of knowledge produced, we employ novel measures based on machine learning (topic modeling) techniques and traditional measures based on bibliometric indicators. Our analysis demonstrates that the shock associated with the introduction of Kinect increased the production of ideas and induced researchers to pursue ideas more diverse than and distant from their original trajectories. We find that this holds for both researchers who had published in motion-sensing research prior to the Kinect shock (within-area researchers) and those who did not (outside-area researchers), with the effects being stronger among outside-area researchers.
THE DEVELOPMENT OF STUDENT’S LEADERSHIP READINESS ASSESSMENT INSTRUMENT IN INDONESIA
Authors: Santoso Thomas Budi , Sudimin Theodorus , Elyadi Rudi
Published: January 2020

The objectives of this study were: (a) to validate a research instrument on Indonesian student leadership readiness; (b) to analyze the student leadership readiness, based on the developed instrument; and (c) to describe the student leadership education programs of some universities in Indonesia. Data collection was carried out through two stages. The first stage of data collection is conducting in-depth interviews with resource persons to compile research instruments distributed in the second stage of data collection. The second stage of data collection was in the form of distributing questionnaires to 1,742 respondents. By using factor analysis, this study succeeded in compiling a research instrument named Student's Leadership Readiness Questionnaire (SLRQ). Ultimately, by employing, the analysis of Pearson Product Moment and Cronbach Alpha, the present paper found that the design of the research instrument on student leadership readiness must first be adjusted. That is, some statement items that are declared invalid are excluded from the design of the research instrument so that the number of question items that were originally 25 statement items was reduced to 18 items. The study found as well that the average student leadership readiness in the universities involved in the study was to be high. Meanwhile, the study found that various programs are constituted as an integral part of the leadership education program. Nevertheless, it is necessary to carry out a more effective leadership education design, especially the integration of academic activities, co-curricular activities, and extra-curricular activities in an integrated manner as a whole unit of Indonesian student leadership education.
THE IMPORTANT OF CREATIVE THINKING ABILITY IN ELEMENTARY SCHOOL STUDENTS FOR 4.0 ERA
Authors: Astuti Astuti , Waluya St Budi , Asikin Mohammad
Published: January 2020

The art of creative thinking needs to develop and taught to students because by thinking creativity, students are able to solve the problem they have, the students become more independent, creating reliable and talented human resources, and skillful in the future. The purpose of this research is to find out the creative thinking ability in the mathematic aspect of Elementary School Mardi Rahayu 02 Ungaran students. The data collection was done by giving four questions of students' creative thinking ability on KPK and FPB materials along with with interview the students. The research was done to 31 students of class IVC. The method used is qualitative descriptive method. Creative thinking ability is important in Era 4.0 where the development of knowledge becomes really fast. The average achievement of every creative thinking indicator is fluency 45,8% and flexibility 58,3%, whereas originality and elaboration indicator reaches 33,3%. The conclusion from this research is that the creative thinking ability of Elementary School Mardi Rahayu 02 Ungaran students need to improve
Computational phase correction algorithms for multi-aperture systems
Authors: Krug Sarah E. , Rabb David J.
Published: January 2020

Aperture cophasing can increase the resolution of a multi-aperture
array while reducing optical system size and accounting for phase
errors from hardware misalignments and atmospheric turbulence.
Remapping apertures using an anamorphic pupil relay can separate the
spatial frequency spectrum of a previously continuous modulation
transfer function to facilitate a
posteriori piston corrections between apertures
[J. Opt. Soc. Am.
A 34, A47
(2017)JOAOD60740-323210.1364/JOSAA.34.000A47]. This study
expands this method from two apertures to six using maximum likelihood
estimation to calculate piston phase errors and least squares for tip
and tilt. Perturbed test targets were generated for specific
turbulence and noise values, providing random realizations of pistons,
tips, tilts, and atmospheric phase screens. Results show improved
Strehl ratios for corrected images in the presence of noise and
atmospheric turbulence.
Compact fiber-optic spectroscopic design and its validation in atmospheric water vapor Raman lidar
Authors: Wang Yufeng , Jia Lisong , Li Xingxing , Fan Fulei , Di Huige , Song Yuehui , Hua Dengxin
Published: January 2020

Spectroscopic systems with compact structure, high reliability, and high stability will push forward the application of lidar in the meteorological and environmental fields as well as space-based and space-borne lidar. Recently, we have successfully designed and verified a new robust fiber-optic spectroscopic Raman lidar for atmospheric water vapor measurements. The compact fiber-optic Raman spectroscopic design was proposed with a cascaded fiber Fabry–Perot filter and a fiber broadband filter, which features an all-fiber-connection structure and a high-spectral-resolution spectrum. These fiber-optic filters have been successfully fabricated in the visible region and matched each other in individual all-fiber Raman channels. The performance of the all-fiber spectroscopic system is measured experimentally, and it is demonstrated that the spectral output from the individual fiber Raman channel provides a bandwidth of 3–4 nm, a central wavelength of 660 nm or 606.7 nm, and an efficient rejection rate of more than

>

10

7

, and it can thus achieve the extraction of vibrational Raman scattering signals from water vapor and from nitrogen molecules in lidar returns and simultaneously reject elastic scattering signals. Furthermore, the fiber-optic spectroscopic Raman lidar was developed at Xi’an University of Technology in Xi’an, China (34.233°N, 108.911°E), and preliminary exploration was carried out for water vapor measurements. Two measurement examples are analyzed to validate the lidar performance and the retrieved water vapor mixing ratio profiles, and its comparisons with Weather Research and Forecasting (WRF) model data also verified the correctness of the lidar data. Despite the limitation of low coupling efficiency by a single-mode optical fiber, atmospheric water vapor measurements up to 700 m were achieved during nighttime under conditions of a 150 mJ laser pulse energy, a 600 mm telescope, and a 5 min integration time. The results validated the concept of all-fiber spectroscopic design and its feasibility for atmospheric water vapor measurements by Raman lidar. The compact fiber-structure characteristics and excellent optical properties provide a new solution to the new spectroscopic technique for operational applications of lidar and space-borne lidar.
Nanoscale dielectric grating polarizers tuned to 4.43 eV for ultraviolet polarimetry
Authors: de Marcos L. Rodríguez , Leong O. B. , Asmara T. C. , Heussler S. P. , Breese M. B. H. , Rusydi A.
Published: January 2020

Transmissive dielectric wire grid polarizers tuned to 4.43 eV (Mg II line, 280 nm), an important diagnostic line for solar physics, are presented in this communication. The polarizers are based on TiO2 gratings and designed with a period of ∼140 nm (7143 lines/mm), 40 nm line width (duty cycle of 0.286), and 100 nm line height. Several gratings are fabricated through electron beam lithography combined with reactive ion etching, whereby two parameters in the nanofabrication process are explored: e-beam dosage on the photoresist and TiO2 etching time. Polarization of samples is optically characterized using a spectroscopic ellipsometer in transmission mode, achieving the best result with an extinction ratio of ∼109 and a transmittance of 16.4% at the target energy of 4.43 eV. The shape of the gratings is characterized through atomic force microscopy (AFM) and scanning electron microscopy (SEM); the measured AFM profiles are distorted by the tip geometry, hence a simple deconvolution procedure is implemented to retrieve the real profile. By analysing the AFM and SEM profiles, we find that the real shapes of the different gratings are close to the design, but with a larger duty cycle than the intended value. With the real grating geometry, an improved model of the best sample was built with a finite-difference time-domain (FDTD) method that matches the result obtained through optical characterization.
Computational aberration correction in spatiotemporal optical coherence (STOC) imaging
Authors: Borycki Dawid , Auksorius Egidijus , Węgrzyn Piotr , Wojtkowski Maciej
Published: January 2020

Spatiotemporal optical coherence (STOC) imaging is a new technique for suppressing coherent cross talk noise in Fourier-domain full-field optical coherence tomography (FD-FF-OCT). In STOC imaging, the time-varying inhomogeneous phase masks modulate the incident light to alter the interferometric signal. Resulting interference images are then processed as in standard FD-FF-OCT and averaged incoherently or coherently to produce cross-talk-free volumetric optical coherence tomography (OCT) images of the sample. Here, we show that coherent averaging is suitable when phase modulation is performed for both interferometer arms simultaneously. We explain the advantages of coherent over incoherent averaging. Specifically, we show that modulated signal, after coherent averaging, preserves lateral phase stability, enabling computational phase correction to compensate for geometrical aberrations. Ultimately, we employ it to correct for aberrations present in the image of the photoreceptor layer of the human retina that reveals otherwise invisible photoreceptor mosaics.
Instabilities in a dissipative soliton-similariton laser using a scalar iterative map
Authors: Meng Fanchao , Lapre Coraline , Billet Cyril , Genty Goëry , Dudley John M.
Published: January 2020

Numerical simulations of a dissipative soliton-similariton laser are shown to reproduce a range of instabilities seen in recent experiments. The model uses a scalar nonlinear Schrödinger equation map, and regions of stability and instability are readily identified as a function of gain and saturable absorber parameters. Studying evolution over multiple round trips reveals spectral instabilities linked with soliton molecule internal motion, soliton explosions, chaos, and intermittence. For the case of soliton molecules, the relative phase variation in the spectrum is shown to be due to differences in nonlinear phase evolution between the molecule components over multiple round trips.
Asymmetric coherence gratings
Authors: Mei Zhangrong , Korotkova Olga
Published: January 2020

We introduce a class of partially coherent, Schell-type sources whose degree of coherence is represented by a finite series of complex-valued functions. The significance of implementing such a series is due to the fact that one can manipulate the weighting coefficients of its terms having a computationally trivial linear phase of the degree of coherence for obtaining the radiated beams of the same complexity as could only be previously achieved with analytically intractable nonlinear phases. Our examples illustrate new opportunities for modeling asymmetric coherence gratings and lattices.
High power, twin-band mid-infrared PPMgLN optical parametric oscillator pumped at 1.679  µm
Authors: Peng Yuefeng , Zhang Jianing , Wang Yong
Published: January 2020

We report on a high-power, twin-band mid-infrared (MIR) periodically poled MgO-doped

L
i
N
b
O

3

(PPMgLN) optical parametric oscillator (OPO) pumped by a near-infrared pulsed OPO with 20 kHz of repetition rate. The pump source has a central wavelength of 1.679 µm and a linewidth of 0.12 nm. The MIR OPO can be tuned from 2.74 to 2.80 µm for signal and from 4.34 to 4.19 µm for idler through raising the oven temperature from 30°C to 200°C, respectively. Under 100°C oven temperature, the OPO yielded maximum total output power of 15.4 W (2.76 µm signal plus 4.29 µm idler) with single-pass pumping configuration. The beam quality

M
2

was measured to be

<

2.5

for signal and

<

4

for idler.
Las opiniones religiosas argelinas sobre la situación de los moriscos en Granada: entre al-Wanšarīsī y al-Magrāwī
Authors: Belkhatir Boumediene
Published: January 2020

Este artículo tiene como objeto analizar la postura de los alfaquíes argelinos hacia el dilema que vivían los moriscos en Granada a partir de 1499, a través del estudio de dos famosas fatuas: la del muftí de Fez al-Wanšarīsī y la del muftí de Orán Aḥmad al-Magrāwī al-Wahrānī, estudiándolas desde los principios de la jurisprudencia islámica (fiqh), y la situación religiosa en la que vivían los moriscos.
La cultura morisca y su importancia en el desarrollo de Argelia en el siglo XVII
Authors: Bara Mohammed Tayeb
Published: January 2020

En la Argelia del siglo XVII, la agricultura tomó una nueva cara con los productos nuevos que trajeron con ellos los moriscos expulsados de España tras la Reconquista. Esos llegaron con nuevas formas de trabajar la tierra y con técnicas de riego muy útiles para una buena higiene de vida no sólo para los humanos, sino también para las plantas lo que muestra que los moriscos se aplicaron en todos los niveles de la economía urbana y suburbana. La artesanía tuvo, a su vez, un papel muy importante en las grandes urbes del Magreb central. Los artesanos moriscos dominaban las técnicas de las cerámicas finas de Al Ándalus, consideradas productos caros y apreciados. Sus piezas eran aptas para muchos usos, técnica que continuaron aplicando a su llegada a tierras del Magreb Central.  Sin embargo, los moriscos destacaron más en el trabajo de la seda, actividad que siguieron desarrollando en sus nuevos destinos, hasta llegar a competir las ciudades argelinas con las españolas  en este dominio. Cambiaron totalmente el sentido del comercio en Argel introduciendo nuevos hábitos de compra y venta de productos. Los moriscos se integraron de distintas maneras según las urbes donde se instalaron. En las ciudades del litoral centro magrebí y algunas del interior no muy alejadas del mar, les acogieron muy bien y adoptaron muchas de sus prácticas. Dichas prácticas perduraron y siguen presentes en la sociedad argelina actual sobre todo en ciudades como Tremecén, Mostaganem, Blida, Cherchel, Argel o Bujía.
المواطنة والرباط الاجتماعي في المدينة الجزائرية: التفكير من خلال مصطلحي القطيعة والتواصل
Authors: Marhoum Farid
Published: January 2020

La continuidad entre períodos y etapas en el espacio de relaciones sociales que se forma en las percepciones de los sujetos mediante la combinación de la imaginación comunitaria y la realidad inmediata es lo que conforma lo que llamamos “sociedad”. Esta hipótesis puede llevarnos a decir que la sociedad es una “comunidad de sujetos agrupados”, una comunidad homogénea que se mueve como un bloque en una misma dirección, o pensar que la sociedad es un “mapa reducible a papel”, una “burbuja cerrada”, una “caja” en la que se ubican los individuos. Pero el estudio de la realidad nos muestra que la sociedad —en este caso la argelina— no funciona de este modo, no está cerrada a los individuos, sino que “los encierra”, los enmarca y equilibra su comportamiento dentro de las instituciones sociales. En este artículo nos preguntamos sobre la validez del argumento: la fuerza o debilidad del tejido social de la sociedad argelina, la tiranía del individualismo, la racionalidad y los intereses privados, y la aparición del ego de los argelinos en espacios metropolitanos. Los actores económicos violentan muchas de las actitudes, pero ¿qué pasa si el individuo argelino está atrapado en la trampa del “egoísmo”, creyendo que es individualismo? Irónicamente, la ciudad no puede absorber las prácticas de la sociedad, que a su vez no logra absorber las prácticas de la ciudad.
Beatriz Alonso Acero, España y el norte de África en los siglos xvi y xvii, Madrid, Síntesis, 2017, 356 pp. [ISBN: 978-84-9171-006-6]
Authors: Donoso Isaac
Published: January 2020

Reseña de: España y el norte de África en los siglos xvi y xviipor: Isaac Donoso
Chemical Modification of Montmorillonite K10 and Its Catalytic Activity
Authors: Sekewael Serly Jolanda , Wijaya Karna , Triyono
Published: January 2020

Montmorillonite K10 (Mt-K10) was chemically modified using a silica-zirconia mixture and the resulting product was named SZMK. The product had an increased total surface acidity, catalytic activity, porosity, and thermal stability. Ammonia adsorption tests and further verification with FTIR and TGA/DTA showed that the acidity of SZMK was higher (0.16 mmol/g) than that of Mt-K10. Catalytic performance was analyzed on the esterification reaction of lauric acid. Refluxing lauric acid and methanol (molar ratio of 1:20) for 20 h with a 20 % (w/w) catalyst showed that catalytic activity of SZMK is high, i.e. methyl laurate production 98.18% (w/w) was achieved.
Enhanced Biosorption of Pb(II) Ions from Aqueous Solutions onto Citric Acid Treated Aspergillus niger Biomass: Equilibrium and Kinetic Studies
Authors: Chintalapudi Vinay Kumar , S.L. Kanamarlapudi Ramya Krishna , Mallu Useni Reddy , Muddada Sudhamani
Published: January 2020

In the present study, initially Aspergillus niger was tested for biosorption of Pb(II) ions and then studied the effect of pretreatment for enhanced biosorption. It was found that the maximum biosorption potential was achieved with citric acid treatment (70.56 %) in comparison with the biomass without treatment (65.46 %) at a biosorbent dose of 20 mg/L, pH 4, 100 rpm, 37 ºC for 8 h. The optimized conditions for treated Aspergillus niger were determined by optimizing the biosorption parameters such as pH, temperature, biomass dose, incubation time and agitation speed. This study indicates that the citric acid treated Aspergillus niger is an effective biosorbent for removal of lead (II) at optimized conditions with the maximum biosorption potential of 83.6 % as compared to previous reported work. SEM-EDX and FTIR analysis showed the structural variations and the functional groups involved in lead biosorption, respectively. Biosorption kinetics showed that pseudo second order kinetic model as the better fit.
Template Synthesis and Characterization of Transition Metal Complexes of
13, 15 and 17-Membered Tetraamide Macrocyclic Disubstituted Dimethyl
Tetrasubstituted Tetraazacycloalka Tetrasubstituted Tetraene Disubstiuted Diol
Authors: Vimala B. , Jayapradha S.R. , Selvan A.
Published: January 2020

A series of new transition metal complexes [ML(Ln)Cl2] where Ln = L13, L15 and L17 (L(13) =
11,13-dimethyl-1,4,7,10-tetraazacyclotrideca-4,6,10,13-tetraene-5,6-diol, L(15) = 9,11-dimethyl-1,4,8,12-tetraazacyclopentadeca-1,3,8,11-tetraene-2,3-diol and L(17) = 10,12-dimethyl-1,4,9,13-tetraazacycloheptadeca-1,3,9,12-tetraene-2,3-diol) and M = Cu(II), Co(II), Ni(II), Mn(II) and Zn(II) have been synthesized by template method. All the synthesized complexes were characterized by IR, UV, ESR, X-ray microanalysis, elemental analysis, thermal studies and magnetic susceptibilities and the geometry of the complexes found to be octahedral.
Synthesis, Molecular Docking, DFT Study of Novel N-Benzyl-2-(3-cyano-4-isobutoxyphenyl)-
4-methylthiazole-5-carboxamide Derivatives and their Antibacterial Activity
Authors: Prabu D. Sam Daniel , Lakshmanan Sivalingam , Thirumurugan K. , Ramalakshmi N. , Antony S. Arul
Published: January 2020

A series of febuxostat based new chemical entities was synthesized using microwave method and characterized by NMR, mass and FT-IR spectral studies. Molecular docking of febuxostat amide nucleus substitution compounds 8c (-7.91kcal/mol), 8g (-7.94 kcal/mol) exhibiting high binding energy against ALK receptors. Theoretical investigation of MEPs, HOMO, LUMO and energy gap of HOMO-LUMO were calculated by B3LYP/6-31G method. Among the tested compounds, methoxy substituted compound 8g showed highest antibacterial activity against S. aereus and B. subtilis.
Musa acuminata L. (Banana) Peel Wastes as Edible Coating Based on
Pectin with Addition of Cinnamomum burmannii Extract
Authors: Ni`mah Lailan , Makhyarini Indri , Normalina
Published: January 2020

Pectin functions as an adhesive and maintains tissue stability so that it can be used in making edible coating to improve the quality of food storage. One of the producers of pectin is Musa acuminata L. peel (containing 22.4 % pectin). In order not to overgrow with microbes, it is also necessary to have antimicrobial property, which can be obtained from Cinnamomum burmannii extract. This study is about raw material preparation, pectin extraction, pectin modification, Cinnamomum burmannii extraction and edible coating manufacturing. The parameters viz. thickness test, water vapour transmission, tensile strength test, elongation at break, biodegradation, and for trials on storing beef sausage showed that 10 % sorbitol was able to withstand the rate of fungal growth for 7 days; 15 % sorbitol was able to withstand the rate of fungal growth for 5 days; and 20 % sorbitol was able to withstand the rate of fungal growth for 3 days.
Co-Doped SnO2 Supported on Activated Carbon: An Efficient Solar Photocatalyst for the Degradation of Rhodamine B
Authors: Kande S.R. , Zaware B.H. , Muley G.G. , Gambhire A.B.
Published: January 2020

A series of SnO2/activated carbon (AC) nanomaterials were prepared by co-doping V(III), Cr(III), Mn(II), Fe(III), Co(III), Ni(II), Cu(II), Zn(II) with nitrogen and sulphur, separately by co-precipitation method, combined with surfactant incorporation method. The as-prepared sample were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectra (XPS), Brunauer-Teller method (BET), diffuse reflectance spectroscopy (DRS), photoluminescence (PL) and Raman spectroscopy. The results showed that the phase composition, crystallite size, BET surface area and optical absorption of samples varied significantly with the nature dopants. The photocatalytic activities of these co-doped SnO2/AC catalysts were investigated by degradation rhodamine B in aqueous solution under solar-light illumination. The results showed an appreciable enhancement in the photoactivity of Fe/N/SnO2/AC as compared to other co-doped SnO2/AC because of smaller particle size, higher specific surface area, photogenerated carrier′s separation and solar light absorption. The degradation rate of rhodamine B dye reached 98 % in 30 min, which is about 10 times higher than that of pure SnO2.
4-Aminoindane Derived Novel Schiff Base Metal Complexes: Synthesis, Characterization, DNA Binding and Molecular Docking Studies
Authors: Arthi S. , Sumalatha D. , Susmitha K. , Bhargavi Manan , Joseph Alina Jyothi
Published: January 2020

A novel Schiff base [SAL-L=2-((2,3-dihydro-1H-inden-4-ylimino)methyl phenol] was synthesized and used as ligand for the synthesis of Ni(II) and Co(II) complexes. The structural characterization of ligand and its Ni(II) and Co(II) complexes was determined using various spectroscopic methods. Based on spectral studies, a square planar and octahedral geometry have been proposed for Ni(II) and Co(II) complexes, respectively. DNA binding properties of these metal complexes with calf-thymus DNA in tris-hydrochloride buffer (pH 7.2) were investigated using UV- visible absorption studies. The binding constants were in the order of 105 M-1 suggested a good binding affinity towards CT-DNA.
The synthesized ligand is docked on TSPO protein showing good binding energy and found to be a potent inhibitor of cancer.
Effect of Seasonal Variation on the Secondary Metabolites and Antioxidant Activity of
Callistemon citrinus (Curtis) Skeels (Myrtaceae) Grown in Eastern Cape of South Africa
Authors: Larayetan Rotimi A. , Abdulrazaq Yahaya , Okoh Omobola O.
Published: January 2020

Callistemon citrinus belong to the kingdom plantae, family Myrtaceae and genus Callistemon. It grows in Australia but has been naturalized in South Africa. It is used as traditional herb to combat both gastro-intestinal and respiratory diseases, pain, diseases caused by bacteria and fungi infection. About 500 g of the air-dried leaves were pulverized each month and subjected to hydro-distillation using a modified Clevenger apparatus. Hydro-distillation of the fresh leaves of C. citrinus gave a pale
yellow volatile oil with a strong scenty fragrance, about 97 components were identified in the 12 treatments analyzed each month. The key components were pinocarvone (1.25-6.17 %), pinocarveol (0.10-9.56 %), α-terpineol (5.24-9.94 %), α-pinene (7.45-22.75 %), limonene (24.08) and eucalyptol (14.69-72.35 %). The compositional profile of the leaves of C. citrinus varied between (January-December). Treatments under investigation revealed markedly qualitatively and quantitatively differences. Antioxidant capacity of the volatile oil of C. citrinus leaves evaluated also demonstrated significance influence of seasonal variation on its activity. The most exigent activity for DPPH free radical scavenging was recorded in the month of September (spring) with an IC50 of 0.50 ± 0.04 mg mL-1, while the most paramount activity for the ABTS assay was 0.94 ± 0.02 mg mL-1 in January (summer).The lowest activity were observed in the June (winter) collection with IC50 of 1.45 ± 0.00 mg mL-1 and 2.19 ± 0.05 mg mL-1 for DPPH and ABTS assays, respectively. Results show that seasonal variations affected the chemical compositions, oil yield as well as antioxidant activities of the volatile oil of the leaves of (C. citrinus); therefore, it is important to consider such effects for industrial and therapeutic purposes.
Synthesis, Characterization and Anti-inflammatory Activity of (2E)-3-(2-Bromo-6-hydroxy-4-methoxyphenyl)-1-(naphthalene-2-yl)prop-2-en-1-one
Authors: Guruswamy Dileep Kumar M. , Jayarama Shankar
Published: January 2020

(2E)-3-(2-Bromo-6-hydroxy-4-methoxyphenyl)-1-(naphthalene-2-yl)prop-2-en-1-one (d1) was synthesized by the Claisen-Schmidt condensation method and characterized by 1H NMR, 13C NMR spectral studies. The anti-inflammatory activity was conducted in Swiss albino rats for paw edema model. Edema was actuated with 1 % carrageenan to every one of the animals following 1 h of the oral medicines. Paw thickness was checked at t = 1, 2, 3, 4, 5 and 24 h. Stair climbing score and motility score were surveyed at t = 24 h. Compound d1 signicant decline in paw thickness at p < 0.001 diminished by 32 % in paw thickness. The compound d1 signicantly expanded the stair climbing and motility score. This study suggested that the compound d1 exhibits remarkable anti-inflammatory activity when compared with that of the standard drug.
Wet Chemical Synthesis of CuO-PVA Hybrid Nanofluid Stabilized by Steric Repulsion
Authors: Albert Annie Aureen , Samuel D.G. Harris , Parthasarathy V.
Published: January 2020

CuO-PVA hybrid nanofluid was synthesized within PVA matrix by a simple wet chemical precipitation method. The influence of rate of addition of precursor (NaOH) on the structure, morphology and stability of CuO-PVA hybrid nanofluids were studied. The structure was confirmed by XRD and UV-visible spectroscopy. High resolution transmission microscopy (HRTEM) images revealed the formation of smaller particles for addition of precursor in solid form or rapid addition (RA), whereas slow addition of precursor (SA) resulted in uniform particle size. The selected area electron diffraction (SAED) pattern of sample SA shows rings with small bright spots indicating that the sample is nano crystalline. The SAED pattern of sample RA shows diffuse rings with lesser number of bright spots indicating that it is less crystalline. The stability studies indicate that both the samples were stable for more than one year.
Ultrasound Assisted Synthesis of 1,5-Disubstituted Pyrazole using Cu(I) Catalyst
Authors: Pise Ashok S. , Burungale Arvind S. , Devkate Santosh S.
Published: January 2020

A new efficient and convenient approach towards the synthesis of pyrazole is described. The α,β-unsaturated cyanoesters were obtained from substituted benzaldehyde and ethyl cyanoacetate by reported methods. 1,5-Disubstituted pyrazoles were synthesized from α,β-unsaturated cyanoester and phenyl hydrazine using sodium ethoxide as a base in the presence of 10 mol % Cu(I) catalyst in high yields within 75-90 min under ultrasound irradiation at 60 ºC. The reaction rate is enhanced tremendously under ultrasound irradiation as compare to conventional methods with improved yields are recorded.
Hexavalent Chromium Adsorption on Magnetic Nanoparticles
Synthesized from Tay Nguyen Red Mud from Vietnam
Authors: Huong Pham Thi Mai , Thu Truong Anh , Thuong Chu Qui , Con Tran Hong , Huong Nguyen Thi
Published: January 2020

Tay Nguyen red mud abundantly found in Vietnam, is a waste product of alumina production formed during processing of bauxite. It is rich in aluminate, residual alkaline, and oxides, such as silicon, iron, and titanium oxides. Iron oxide, which constitutes 45-55 % of Tay Nguyen, is useful for Fe3O4 nanoparticles synthesis. In this study, a Fe3O4 nanoparticles were synthesized using Tay Nguyen by the chemical co-precipitation method, which required a non-oxidizing oxygen-free environment. Fe3O4 nanoparticles were characterized using X-ray diffraction, field emission scanning electron microscopy,
Brunauer-Emmett-Teller analysis, and vibrating-sample magnetometry. Adsorption of hexavalent chromium by the nanocomposite was conducted under batch conditions. Pseudo-second-order equations were used to describe kinetic data of adsorption reactions; the equations were fitted to kinetic data as shown by the results. The isotherms of adsorption were also studied using the linear forms of the Langmuir and Freundlich equations. The Langmuir equation exhibited higher linear correlation with
the experimental data than the Freundlich equation did. The maximum monolayer coverage, qmax at 297 K was 31.44 mg/g.
Synthesis, XRD, EXAFS and XANES Study of Cu(II) Complexes of Aniline Dithiocarbamate
Authors: Geete Anurag , Shrivastava B.D. , Mishra Ashutosh
Published: January 2020

In present investigation, seven copper(II) complexes were synthesized using various aniline
dithiocarbamate. The synthesized Cu(II) complexes were studied for different structural and chemical parameters using XRD, EXAFS and XANES. The output obtained from X-ray studies was synthesized using Athena and Origin 6.0 software. The results of the investigation were used in determining the structures of the synthesized complexes. The particle size of the synthesized complexes ranged between 46.7 and 125.3 nm. The lattice constant of Cu(II) complexes was found 3.61-3.62 Å.
Stability Indicating RP-HPLC Method Development and Validation for Dexamethasone
Authors: Kulkarni Pankaj N. , Jadhav C.K. , Nipate A.S. , Dodake-Supekar Alaknanda M. , Gill C.H.
Published: January 2020

A new, simple, reliable and reproducible stability indicating RP-HPLC assay method has been developed for quantitative analysis of dexamethasone from dexamethasone tablets. This developed method has been validated according to ICH guideline with respect to system suitability, specificity, precision, linearity, accuracy and robustness. An isocratic condition of mobile phase water (0.1% orthophosphoric acid):acetonitrile in a ratio of 60:40, v/v at a flow rate of 1.0 mL/minute over RP 2.5 Fortis C18, 100 × 4.6 mm, 2.5 μm, column was at 27 ºC maintained. This method is specific and showed excellent linear response with correlation coefficient (R2) values of 0.999. In forced degradation, the proposed method has been investigated with different stress conditions as hydrolytic, oxidative, thermal and humid as recommended by ICH guidelines. An accurate and reliable reversed-phase HPLC method for the analysis of dexamethasone in dexamethasone tablets was developed and validated successfully.
Theoretical Verification of Dielectric and Magnetic Properties of Polyaniline-Nickel Ferrite Nanocomposites Synthesized in Green Medium Extracted from the Fruit of Tamarindus indica
Authors: Smitha T.R. , Bhadran Thushara , Shanker Vaishali , Prema K.H.
Published: January 2020

Nanocomposite materials of nickel ferrite incorporated polyaniline (PANI) have been synthesized via in situ oxidative polymerization technique in a green medium extracted from the fruit of plant Tamarindus indica. Synthesized particles were characterized by FT-IR spectroscopy, X-ray diffraction technique and scanning electron microscopy. Various samples of composites were prepared with 5, 10 and 15 g of filler nickel ferrite and the variation in dielectric permittivity is calculated by measuring the capacitance of the materials in various external frequency ranges from 100 Hz to 20 MHz. Experimental values of dielectric property are compared with theoretical values obtained from Maxwell-Wagner equation. The magnetic properties such as saturation magnetization (Ms), magnetic remanance (Mr) and coercivity (Hc) of the samples were analyzed by vibrating sample magnetometer (VSM). Retention of the magnetic filler in the PANI matrix is evaluated by comparing the experimental Ms values of the composites with the values computed from a theoretical linear equation. The experimental results were well fitted with the theoretical values and confirmed the synthesis of PANI-nickel ferrite composites with desired electrical and magnetic properties by varying the amount of components.
Synthesis, Crystal Structure and Hirshfeld Surface Analysis of
3,14-Dimethyl-2,6,13,17-tetraazatricyclo(16.4.0.07,12)docosane-2-(nitric acid)
Authors: Moon Dohyun , Jeon Sunghwan , Ryoo Keon Sang , Choi Jong-Ha
Published: January 2020

The crystal structure of 3,14-dimethyl-2,6,13,17-tetraazatricyclo(16.4.0.07,12)docosane-2-(nitric acid), C20H40N4·2(NO2OH) had been determined using synchrotron radiation at 220 K. The compound crystallized in the space group P21/n of the monoclinic system with two mononuclear formula units in a cell of dimensions a = 9.1930(18), b = 10.120(2), c = 12.979(3) Å and β = 101.06(3)º. The asymmetric unit contains half a centrosymmetric macrocycle and one nitric acid molecule. There were two molecules in the unit cell. In structure of macrocycle, C-C and N-C bond lengths were in the range 1.5198(19) to
1.5367(18) Å and 1.4744(16) to 1.4986 (16) Å, respectively. The NO2OH group has one longer N-O bond of 1.3441(18) Å and two shorter N-O bond of 1.2509(19) Å and 1.2510(19) Å, and O-N-O angles of 126.31(14)º, 117.98(14)º and 115.71(14)º. The N-H···O and N-H···N hydrogen bonds interconnect macrocycle (C20H40N4) with nitric acid molecules while two O-H···O hydrogen bonds link the nitric acid molecule to neighboring nitric acid molecule each other. The molecule was stabilized by forming intermolecular N-H···O, N-H−N and O-H···O hydrogen bonds. Hirshfeld surface analysis by 3D molecular surface contours and 2D fingerprint plots have been used to analyze intermolecular
interactions present in the crystal.
Prevalence evaluation of apical periodontitis and its relationship with endodontic and restorative treatment in a community in Southern Brazil
Authors: Saporiti Julia Machado , Gomes Andressa , Damian Melissa Feres , Ferreira Nadia de Souza
Published: January 2020

Objective: The aim of this study was evaluate radiographically prevalence of apical periodontitis (AP) in endodontically treated teeth (ETT) and relate with demographic factors, quality of endodontic treatment and coronal restoration. Material and methods: Data were collected from dental records wich contained full-mouth radiographic series. In ETT, arch, dental group and presence of AP were evaluated. Quality of root canal filling, presence and quality of coronal restoration and type of restorative material were also collected. Data were evaluated using descriptive statistics and Chi-square Test. Results: Of 70 patients included in the final sample, the majority were female (54.3%) and age ranged from 13 to 77 years (47.14 ± 13.18). Of 1,333 teeth evaluated, 73 (5.4%) had endodontic treatment, being the majority maxillary (74%) and anterior teeth (52.1%). Of teeth without endodontic treatment, 320 (25.4%) had AP. Failure rate was high (52.8%) and quality of root canal filling and coronal restoration were considered inadequate in majority cases (58.3% and 47.7%, respectively). Dental group had a statistically significant relationship with presence of AP in ETT, being more frequent in anterior teeth (p = 0.019). Conclusion: It was concluded that prevalence of AP in ETT was high and dental group was the factor that most influenced prevalence of AP in ETT.KeywordsApical periodontitis; Radiography; Root canal filling.