bluuebunny/crossref_metadata_2025 huggingface dataset:
Synchrotron Cutoff in Ultraluminous X-Ray Sources
Authors: Ghosh Tanuman , Sethi Shiv , Rana Vikram
Published: May 2023

The origin of spectral curvature at energies E ≃ 10 keV in ultraluminous X-ray sources (ULXs) is not well understood. In this paper, we propose a novel mechanism based on synchrotron radiation to explain this cutoff. We show that relativistic plasma can give rise to the observed spectral curvature for neutron star magnetic fields due to the variation in the latitude of synchrotron radiation. We analyze the NuSTAR data of two bright pulsar ULXs, NGC 5907 ULX1 and NGC 7793 P13, and provide estimates of the physical parameters of these sources. We fit the data for synchrotron emission at various latitudes and show that the spectral cutoff in these cases can be explained for a large range of acceptable physical parameters, e.g., a semirelativistic plasma with γ ≃ 20 for high latitudes or a highly relativistic plasma (γ ≃ 105) for emission close to the electron’s orbital plane in a typical magnetic field of B ≃ 1012 G. We also discuss how such an emission mechanism can be distinguished from other proposed models. A corollary to our study is that most ULXs might be neutron stars as they display such a spectral cutoff.
Starspot Mapping with Adaptive Parallel Tempering. II. Application to TESS Data for M-dwarf Flare Stars AU Microscopii, YZ Canis Minoris, and EV Lacertae
Authors: Ikuta Kai , Namekata Kosuke , Notsu Yuta , Maehara Hiroyuki , Okamoto Soshi , Honda Satoshi , Nogami Daisaku , Shibata Kazunari
Published: May 2023

Starspots and stellar flares are indicators of stellar magnetic activity. The magnetic energy stored around spots is thought to be the origin of flares, but the connection is not completely understood. To investigate the relation between spot locations deduced from light curves and the occurrence of flares therein, we perform starspot modeling for the TESS light curves of three M-dwarf flare stars, AU Mic, YZ CMi, and EV Lac, using the code implemented in Paper I. The code enables us to deduce multiple stellar/spot parameters by the adaptive parallel tempering algorithm efficiently. We find that flare occurrence frequency is not necessarily correlated with the rotation phases of the light curve for each star. The result of starspot modeling shows that any spot is always visible to the line of sight in all phases, and we suggest that this can be one of the reasons why there is no or low correlation between rotation phases and flare frequency. In addition, the amplitude and shape of the light curve for AU Mic and YZ CMi have varied in two years between different TESS cycles. The result of starspot modeling suggests that this can be explained by the variations of spot size and latitude.
The Initial Mass Function and Other Stellar Properties Across the Core of the Hydra I Cluster*
Authors: Lonoce Ilaria , Freedman W. L. , Feldmeier-Krause A.
Published: May 2023

The Hydra I cluster offers an excellent opportunity to study and compare the relic old stellar populations in the core of its two brightest galaxies. In addition, the differing kinematics of the two galaxies allows a test of the local validity of general scaling relations. In this work, we present a direct comparison employing full spectral fitting of new high-quality long-slit optical and near-infrared spectroscopic data. We retrieve age, metallicity, and 19 elemental abundances out to ∼12 kpc within each galaxy, as well as the Initial Mass Function (IMF) in their central regions. Our results suggest that the inner ∼5 kpc regions of both galaxies, despite their different masses, formed at the same time and evolved with a similar star formation timescale and chemical enrichment, confirming their early formation in the cluster buildup. Only the overall metallicity and IMF radial profiles show differences connected with their different velocity dispersion profiles. The radial trends of the IMF positively correlate with both [Z/H] and σ. While the trends of the IMF slope values with metallicity agree with a global trend for both galaxies, the trends with the velocity dispersion exhibit differences. The outer regions show signs of mixed stellar populations with large differences in chemical content compared to the centers, but with similarly old ages.
Turbulence and Diffusive Transport of Cosmic Rays in the Very Local Interstellar Medium
Authors: Florinski V. , Alonso Guzman J. G. , Giacalone J. , le Roux J. A. , Opher M.
Published: May 2023

We study the transport of fast charged particles, such as galactic cosmic rays, in the very local interstellar medium (VLISM), which is currently being explored by the two Voyager space probes. Guided by the observations of magnetic fluctuations, the paper develops a simple theoretical framework for computing scattering rates and spatial diffusion coefficients that can be used to model cosmic-ray transport in the VLISM. The local interstellar magnetic turbulence is represented as a superposition of (a) Alfvénic, (b) transverse 2D, and (c) longitudinal components obeying distinctive geometry rules in the plasma frame. The model is based on the weakly nonlinear formalism where particle trajectory’s deviation from the unperturbed helix is caused primarily by guiding-center diffusion across the mean magnetic field. The transverse component plays the dominant role in perpendicular diffusion, while the longitudinal component has only a minor effect. Pitch-angle scattering is extremely weak in the VLISM, so that cosmic-ray transport can be considered essentially scatter-free on heliospheric scales. We test our theoretical model with the help of particle orbit simulations to find good agreement for perpendicular diffusion. We also find that cosmic rays disperse faster than in a conventional random walk (diffusive) process if the turbulence power spectrum contains fluctuations whose wavelength is larger than the size of the heliosphere.
A Nonrepeating Fast Radio Burst in a Dwarf Host Galaxy
Authors: Bhandari Shivani , Gordon Alexa C. , Scott Danica R. , Marnoch Lachlan , Sridhar Navin , Kumar Pravir , James Clancy W. , Qiu Hao , Bannister Keith W. , T. Deller Adam , Eftekhari Tarraneh , Fong Wen-fai , Glowacki Marcin , Prochaska J. Xavier , Ryder Stuart D. , Shannon Ryan M. , Simha Sunil
Published: May 2023

We present the discovery of an as yet nonrepeating fast radio burst (FRB), FRB 20210117A, with the Australian Square Kilometre Array Pathfinder (ASKAP), as a part of the Commensal Real-time ASKAP Fast Transients Survey. The subarcsecond localization of the burst led to the identification of its host galaxy at z = 0.214(1). This redshift is much lower than what would be expected for a source dispersion measure (DM) of 729 pc cm−3, given typical contributions from the intergalactic medium and the host galaxy. Optical observations reveal the host to be a dwarf galaxy with little ongoing star formation—very different to the dwarf host galaxies of the known repeating FRBs 20121102A and 20190520B. We find an excess DM contribution from the host and attribute it to the FRB’s local environment. We do not find any radio emission from the FRB site or host galaxy. The low magnetized environment and the lack of a persistent radio source indicate that the FRB source is older than those found in other dwarf host galaxies, establishing the diversity of FRB sources in dwarf galaxy environments. We find our observations to be fully consistent with the “hypernebula” model, where the FRB is powered by an accretion jet from a hyperaccreting black hole. Finally, our high time resolution analysis reveals burst characteristics similar to those seen in repeating FRBs. We encourage follow-up observations of FRB 20210117A to establish any repeating nature.
Central BH Mass of Tidal Disruption Event Candidate SDSS J0159 through Long-term Optical Variabilities
Authors: Zhang XueGuang
Published: May 2023

In this manuscript, central BH mass is determined in the tidal disruption event (TDE) candidate SDSS J0159, through the 9 yr long variabilities, in order to check whether the virial BH mass is consistent with the mass estimated by other independent methods. First, the host galaxy spectroscopic features are described by 350 simple stellar templates, to confirm the total stellar mass of about 7 × 1010
M
⊙ in SDSS J0159, indicating the virial BH mass is about two magnitudes larger than the BH mass estimated by the total stellar mass. Second, based on an efficient method and fitting procedure, through the theoretical TDE model applied to describe the Sloan Digital Sky Survey ugriz-band light curves of SDSS J0159, the central BH mass can be determined as

M

BH

∼

4.5

−
1.1

+
1.3

×

10

6

M

⊙

, well consistent with the Mσ
relation expected BH mass and the total stellar mass expected BH mass. Third, the theoretical TDE model with the parameter of central BH mass limited to be higher than 108
M
⊙ cannot lead to reasonable descriptions of the light curves of SDSS J0159, indicating central BH mass higher than 108
M
⊙ is not preferred in SDSS J0159. Therefore, the TDE model determined central BH mass of SDSS J0159 is about two magnitudes lower than the virial BH mass, to support central broad-line regions, including accreting debris contributions from central TDE, and provide interesting clues to reconfirm that outliers in the space of virial BH mass versus stellar velocity dispersion should be better candidates of TDE.
Unilateral Cicatrizing Conjunctivitis and Large Conjunctival Cyst After Preseptal Cellulitis in a 6-Year-Old Boy
Authors: Paciuc-Beja Miguel , McCourt Emily
Published: May 2023

A case of unilateral cicatrizing conjunctivitis in a 6-year-old boy after preseptal cellulitis on the same side is described. An excisional biopsy of the cyst was performed and conjunctival tissue was sent for immunological examination. The authors concluded that preseptal cellulitis was associated with cicatrizing conjunctivitis in the patient.
[J Pediatr Ophthalmol Strabismus 2013;50:e47–e48.]
Effect of the calcination temperature of the FTO/PbS cathode on the performance of a quantum dot-sensitized solar cell
Authors: Tung Ha Thanh , Dan Ho Kim , Phuc Dang Huu
Published: May 2023

As a cheaper alternative to the industrial Pt electrode used in quantum-sensitized solar cells, the electrophoresis process is employed to create the low-cost FTO/PbS cathode. For structural cubic and sizes ranging from 40 nm to 200 nm, structure and morphology were investigated using high-resolution scanning electron microscopy and X-ray diffraction. The conversion efficiency of solar cells is significantly impacted by the calcination temperatures of cathodes at 100 ℃, 150 ℃, 200 ℃, and 300 ℃ under vacuum. The FTO/PbS cathode electrode was therefore calcined at 150 ℃ with a maximum efficiency of 3.938%. This happens as a result of the complete fusion of PbS nanoparticles with crystal at 150 ℃, which reduces resistance and increases electron lifetime compared to other temperature combinations.
Nonlocal finite difference discretization of a class of renewal equation models for epidemics
Authors: Messina Eleonora , Pezzella Mario , Vecchio Antonia
Published: May 2023

In this paper we consider a non-standard discretization to a Volterra integro-differential system which includes a number of age-of-infection models in the literature. The aim is to provide a general framework to analyze the proposed scheme for the numerical solution of a class of problems whose continuous dynamic is well known in the literature and allow a deeper analysis in cases where the theory lacks.
Japanese Dramas and the Streaming Success Story That Wasn’t: How Industry Practices and IP Shape Japan’s Access to Global Streaming
Authors: Humphery David
Published: May 2023

I examine the relative absence of Japanese dramas in the global streaming landscape. Contrasting this to their 1990s and 2000s boom in East Asia, I argue that structural rather than cultural factors play a central role in this development. At present, a split exists between the domestic market for Japanese dramas and the transnational one, where only a few, largely off-mainstream dramas find traction. Through a discussion of streaming’s prehistory and present in Japan, I contend that the split stems, in part, from three issues: television networks’ continued dominance, industry practices that favor advertising-based revenue models, and the adoption and impact of international intellectual property regimes on Japan’s media industry in general. I argue that these issues and the split that they inform stand to have significant consequences for Japanese dramas, as well as other media genres, in the emergent era of streaming. Although Japan’s media industry has largely been able to navigate the incursion of US-based streamers into its domestic market and maintain control there, it has become increasingly reliant on mostly US-based platforms to distribute its content abroad.
How Pachinko Mirrors Migrant Life: Rethinking the Temporal, Spatial, and Linguistic Dimensions of Migration
Authors: Wu Winnie Yanjing
Published: May 2023

This paper critically analyzes the Apple TV+ series Pachinko (2022) to comprehend its cross-historical and cross-regional metanarrative unfolding from the organization of temporality, spatiality, and language. As the TV adaptation of Min Jin Lee’s eponymous novel, Pachinko depicts a family’s migration journey from Korea to Japan after the 1910s and emphasizes their suffering from systemic discrimination against temporary Korean residents. Produced by talents from Korea, Japan, and the United States, Pachinko displays strong hybridization that combines American TV conventions with a distinct East Asian culture and history. The hybridized, multicultural, and multilingual background of the production necessitates a transnational and interdisciplinary framework to analyze its critical success and cultural implications. Expanding Harvey’s notion of time-space compression, the paper conceptualizes the temporal and spatial experience of watching a transnational production via global streaming as a mirrored experience of migrant life. It tackles television dramas as a strategy to understand contemporary migration and globalization by first outlining the evolutionary trajectory of television, and then identifying the movements, mobility, and the transnational cultural flows in Pachinko. Moreover, this paper analyzes the linguistic aspects of Pachinko, particularly in translation and multilingualism, to establish a connection between language and cultural identities. Inquiring into previous literature on translation, this paper also seeks to understand the complexity of communicating in multiple languages, both literally and metaphorically. Finally, this paper examines how migration and migrants are reimagined in Pachinko at a time when national borders and cultural and linguistic barriers are quickly eroded by global streaming TV.
Investigation of Purchasing Applications After Digital Change in Industrial Markets
Authors: Avcı Ayla
Published: May 2023

In the constantly developing and changing global markets, the demands and demands of consumers also change. There have been changes in the industrial markets where too many products and services are bought and sold. World countries have become a common market thanks to the internet usage, which is widely used all over the world. The needs and wishes of consumers have also differentiated with cultural interaction. With the rapid increase in the online shopping method, internet shopping has started to rise with the fast and timely delivery options of the products. Demand for fast purchasing and product diversity have also increased in complex industrial markets where many people make purchases. Recently companies have entered the period of using online web pages in supplier selection. In this research, purchasing processes in industrial markets and new area digital transformation processes are examined.
Internal Audit Functions in Cyber Security Governance
Authors: Selimoğlu Seval Kardeş , Saldı Mustafa Hakan
Published: May 2023

Cyber-attacks have been brought into the critical risk category with rising technology usage and emerging developments in digital transformation that have been dominating service sectors like banking. The assurance of the validity of the activities, which are being coordinated in cyber security governance mechanisms of the banks, is needed to ensure the financial transactions are being driven between acceptable risk levels. The control of risk management operations for cyber security processes should be performed with the support of audit units of the banks. Because of the forementioned reasons, the responsibility fields of internal audit teams in cyber security management processes are deeply examined through the Delphi technique in this chapter, which is derived from the doctoral thesis research study. On this basis, blockchain technology is going to be explored from the point of technical concepts and policy framework to propose a set of solutions for continuous audit methods in cyber security governance.
The Impact of Blockchain Technology on Accounting, Auditing, and Assurance Practices
Authors: Selimoglu Seval , Yesilcelebi Gul , Altunel Mehtap
Published: May 2023

The purpose of this study is to examine the impact of blockchain technology on accounting, auditing, and assurance practices. For this purpose, the relevant national and international literature on the accounting, auditing, and assurance practices of blockchain technology has been reviewed. As a result of the research, the advantages and disadvantages of blockchain technology were evaluated and categorized. As a result of the study, it has been determined that the blockchain technology has a great effect on accounting, auditing, and assurance.
Marketing Information Products and Services in the Digital Age in the Academic Library Environment
Authors: Olubiyo Peter Olubunmi
Published: May 2023

Library and information centers have begun to realize that by using marketing principles and techniques, they can understand better their users' needs, justify finding, communicate more effectively with a variety of internal and external audiences, and achieve greater efficiency and result in delivering product and services that meet the identified needs of their client. In contemporary society, people can now easily access information and information-bearing resources on the go if they relate to their laptops, smartphones, iPad, etc. Even though users can have access to information via the internet and other technology, the fact remains that the place of the library in society cannot be put aside. As such, librarians are now dwelling in a highly competitive world of marketing.
Trust in Electronic Banking With the Use of Cell Phones for User Satisfaction
Authors: Medina-Quintero Jose Melchor , Ortiz-Rodriguez Fernando , Tiwari Sanju , Saenz Francisco Isai Morales
Published: May 2023

Mobile technologies play a transcendental role in the development of organizations. The banking industry has become the world's economic engine, and when combined, they seek to generate a competitive advantage and attract more users. For this reason, this research aims to determine the influence of users' trust in their satisfaction when they use e-banking through mobile phones. A survey was applied to 98 users in Northeastern Mexico who use a commercial banking computer application and inferential analysis with SmartPLS. The main results indicate that trust is essential in using this computer technology to perceive its usefulness and ease of use. However, the most relevant contribution is the use of e-banking by providing greater satisfaction to users.
Political Marketing App Based on Citizens
Authors: Barrera Ruben Mizael , Martinez-Rodriguez Jose L. , Tiwari Sanju , Barrera Viridiana
Published: May 2023

The chapter addressed what smartphones, mobile applications, programming languages, and mobile operating systems are. The development, implementation, and results obtained from mobile applications in the following areas are discussed in detail: educational platforms, citizen participation with the government, teaching the pronunciation of the English language, and citizen participation in public security. Android, being the main operating system for smartphones, is the most suitable for the development of mobile applications since it guarantees that it will have the greatest possible visibility and reach, not only for its popularity but for its presence in many devices other than cell phones and its “open system” feature so that everyone who wants it can develop compatible software.
English as a Main Driver for International Business
Authors: Rodriguez-Elizondo Areli Y. , Barrera Ruben Mizael , Barrera Viridiana , Tijerina Gerardo
Published: May 2023

The city of Reynosa, Tamaulipas is full of maquiladoras that come from abroad to settle. In turn, these export mostly to the United States, because Reynosa is a border with the aforementioned country. Businesses and agreements have been created that until now have prospered successfully. Speaking English has long ceased to be an added value, and its importance is increasingly evident to professionals and companies, who see this language as the door to better job opportunities, expansion into the world, and new businesses. In Reynosa, there are about 125,945 students pursuing a university degree, among which are, to mention a few: bachelor's degree in economics, international trade, computer systems engineering, architecture, production systems engineering, industrial engineering, and mechatronics engineering, among others. The present research is expected to show the main factor as to why students from 18 to 23 years old in Reynosa, Tamaulipas between 2022 and 2023 are interested in learning English.
Six-Stage Pyramid Model for the Implementation of a Holistic Sustainability Approach in Higher Education Institutions (HEIs)
Authors: Krause Julia
Published: May 2023

Since 2015, society and businesses have been urged to implement procedures that would help to achieve the UN's 17 sustainable development goals. Higher education institutions want to become drivers of modern change and to contribute to achieving those targets agreed upon in Paris. Universities are encouraged to provide the required knowledge to the future employees and leaders, and also to act as an example of a sustainable organisation. And this means not just to talk about the required challenges and changes, not just to teach sustainability courses, but to implement the sustainability in its full range into HEI´s own procedures. That would provide a holistic approach. The aim of the chapter is to create a model that would enable to see the whole picture and help HEIs find their way to a more holistic approach to tackling sustainability issues at universities.
Socio-Economic, Political, and Environmentally Sustainable Development Considerations of Transitional Innovation
Authors: Vargas-Hernandez José G. , Vargas-González Omar C.
Published: May 2023

This study aims to analyze socio-economic, political, and environmentally sustainable development considerations of transitional innovation. It departs from the assumption that any innovation transition must be well supported by environmental and socio-ecological economics frameworks to bring a new set of different methodological approaches and assumptions leading to the socio-ecological transition of innovation. The method employed is the meta-analytical-descriptive and reflective based on the theoretical and empirical review of the literature. It concludes that any socioecological transition of innovation requires to be supported by socio-economic, political, and environmentally sustainable development.
Sustainable Performance Evaluation for European Airports With Principal Component Approach
Authors: Turan Hakan , Bulak Muhammet Enis
Published: May 2023

Transportation has a critical role in society and considerable negative effects on the environment, such as air pollution, land use changes, and greenhouse gas emissions. Especially, the high carbon emissions in the aviation sector increase the importance of studies in the field of sustainability. In this study, an eco-efficiency performance analysis is presented among 14 selected airports from Europe. Four environmental indicators (energy consumption, greenhouse emissions, water consumption, and waste generation) and three value-added indicators (revenue, passenger, and employee) were used for the analysis. The sustainable performance levels of the selected airport were compared with the help of principal component analysis (PCA). The data required for the assessment were obtained from the GRI and annual sustainability reports. Regarding eco-efficiency and clustering analysis, Malta airport emerged as the most eco-efficient and sustainable airport in Europe relying on the indicators and the datasets acquired.
Fuzzy-AHP and Fuzzy Saw Application for Sustainable Supply Chain Management
Authors: Bulak Muhammet Enis , Turan Hakan
Published: May 2023

Sustainable supply chain management (SSCM) governs material, information, and capital flows. One of the most important operational responsibilities for carrying out SSC operations is the assessment and selection of a supplier. SSC performance indicators are critical for such operations. Current studies consider only partial aspects and do not include the triple bottom lines of sustainability. In this regard, the authors developed a metric that includes environmental, social, and economical indicators concerning supplier evaluation. The Fuzzy-AHP methodology was adopted to capture more consistent results among the indicators. These indicators were determined with a comprehensive literature review and validated by 6 supply chain experts. Analysis was carried out with Fuzzy-AHP to indicate the most critical indicators by calculating those weights. Fuzzy SAW was implemented to validate the results. Relying on the outcomes, social indicators are revealed to be the most important factors in SSCM.
Analysis of the Impact of Corporate Governance on Sustainability for BIST Companies
Authors: Turhan Gokce Tekin
Published: May 2023

Considering the economic, environmental, and social dimensions of corporate governance and corporate sustainability together will bring competitive advantage to businesses as well as efficiency and productivity. From this point of view, it is obvious that developments in corporate governance and corporate sustainability may have positive reflections on the performance of businesses. A good governance structure concerns not only shareholders, but also society and stakeholders. Today, in addition to financial performance, ESG scores also play an active role in increasing the value of companies. If companies give more importance to environmental and social activities, the trust of the stakeholders and society in the company increases and a positive reputation is formed towards the company. The aim of the study is to analyze the relationship between Borsa Istanbul corporate governance index and sustainability index for the period 2016.01-2022.01. As a result of the cointegration analysis, it was determined that the corporate governance index was 51.7% related to the sustainability index.
Does Economic Development Have a Causal Relationship With Environmental Degradation?
Authors: Singh Ajay Kumar , Sharma Aditya Kumar , Jyoti Bhim
Published: May 2023

This study estimated the cause-and-effect relationship between economic development and environmental degradation in 92 countries using a Cobb-Douglas production model. The empirical findings found a positive and bi-directional causal association between economic development and environmental degradation across countries. The economic development enhancing factors were key drivers to increase environmental degradation. In contrary, environmental degradation promoting factors such as CO2 intensity, industrialization, urbanization, energy consumption, and agricultural production activities showed a positive impact on economic development. The empirical results also suggested that the impact of a few variables on environmental degradation and economic development differed in high, upper-middle, lower-middle, and low-income countries.
The Effect of Elliptical Form of Cylinder on Free Convection in Annular Space
Authors: Zoubai Dr. Elhadi , Bouhamida Bachir
Published: May 2023

We try through this research to present a detailed study on free convection heat transfer inside a closed space. The work is carried out in numerical way, using the method called finite volume. The governing equations are solved for numerical simulations of steady state and laminar regime. The studied domain is an annular space consisting mainly of two cylinders positioned horizontally, the inner cylinder has an elliptical shape with different aspect ratio (E) while the outer one has a single shape which is circular. The primary conditions adopted in this research are as follow: the outer cylinder has a cold surface, while the inner cylinder has a cold surface. The space between cylinders is considered to be filled with fluid of different values of thermo-physical proprieties (Pr). The fluid in the space moves under the influence of thermal buoyancy which is controlled by Ri number. The pertinent parameters for this research are: the aspect ratio of elliptical cylinder which is E = 0.1 to 1, the Prandtl number Pr = 1 to 100 and finally the Richardson number Ri = 103, 104 and 105. The results of this work show that the elliptical form allows an increase in thermal transfer activity. Also, values of the number Pr have a limited effect on heat transfer.
Heat Transfer Coefficient of 7050 Aluminum Alloy under Different Quenching Medium Parameters
Authors: Tong You Zhi , Li Ya Nan , Li Xi Wu , Ren Wei Cai , Zhang Yong An
Published: May 2023

In this study, the heat transfer coefficients of 7050 aluminum alloy under different water temperatures, polyalkylene glycol aqueous solution concentrations and quenching medium types are calculated by an iterative method, and the heat transfer coefficient of the aluminum alloy under different quenching medium parameters was compared and the difference was discussed in detail. The results show that with the increase of water temperature, the heat transfer coefficient of 7050 aluminum alloy gradually decreases; with the increase of polyalkylene glycol aqueous solution concentration, the heat transfer coefficient gradually decreases; the order of heat transfer capacity of quenching medium is disclosed among the studied medium types.
Improving Structure and Electrochemical Performance of Single-Crystal Ni-Rich Cathodes by Aluminium Doping
Authors: Wu Feng , Zhang Shi Shi , Li Ning , Nie Yuan Lin , Chen Lai , Cao Duan Yun , Lu Yun , Su Yue Feng
Published: May 2023

Ni-rich layered oxide cathode materials LiNixCoyMnzO2 (x>0.6) have been widely used in high specific energy Li-ion batteries. Compared with polycrystalline LiNixCoyMnzO2, single crystal Ni-rich cathode materials have attracted much attention for their unique advantages. However, they also suffer from some drawbacks, such rapid capacity decay and intragranular crack during cycling. In order to enhance the structure and electrochemical performance of single crystal LiNi0.8Co0.1Mn0.1O2 (SC811), different amount of aluminium (1 mol%, 2 mol% and 3 mol%) is utilized to substitute the materials. Physical characterizations of SC811 show the successful synthesis and Al doping of the single-crystal materials as well as lower Li/Ni intermixing after Al doping. Electrochemical tests illustrate that the single-crystal materials doped with 2mol% Al (2Al-SC811) shows superior electrochemical performance, and maintains 83.5 % of the initial discharge capacity after 100 cycles at 1 C in comparison with 68.9 % of the pristine SC811. It is hoped this work should shed light on the development of advanced cathode materials for Li-ion batteries.
Effects of Aluminum Source with Different Properties on the Properties of Pd/SAPO-41 and its Catalytic Hydroisomerization Reaction
Authors: Bai Xue Feng , Wu Wei
Published: May 2023

Aluminium source is one of the main factors affecting the physicochemical properties of SAPO-41.Silicoaluminophosphate molecular sieves-SAPO-41 were prepared via hydrothermal synthesis using di-n-butylamine (DBA) as templating agent, pseudo-boehmites, phosphoric acid and silica sol as aluminum, phosphorus and silicon sources respectively. Using XRD, N2 physical adsorption, SEM and Py-IR analysis media, the effects of aluminum sources on the crystal and pore structure, morphology, B-acid center strength of the prepared SAPO-41 molecular sieves. The catalytic hydroisomerization performance over Pd/SAPO-41 bifunctional catalysts were investigated. Pseudo-boehmite type has little effect on the crystal structure and chemical composition of SAPO-41 molecular sieve, but has different effects on its morphology, pore structure, B-acid strength of SAPO-41, and Pd dispersion on Pd/SAPO-41. The hydroisomerization conversion of n-decane over 0.5Pd/S41-A1 can reach 88.56 %, and the selectivity of isoparaffin can reach 90.88%.This work provides a reference for selecting an ideal aluminum source for the synthesis of SAPO-41.
Grain Refinement Enhanced Tensile Strength, Fracture Toughness and Fatigue Crack Propagation Resistance of a High Zn-Containing Al-Zn-Mg-Cu Alloy
Authors: Lin Hai Tao , Wen Kai , Li Xi Wu , Zhou Hua , Li Ya Nan , Xiong Bai Qing
Published: May 2023

In present work, a high Zn-containing Al-Zn-Mg-Cu alloy with different grain sizes was fabricated by extrusion and related precipitation characteristics and mechanical property were investigated after uniform heat treatments. The results showed that precipitation characteristics for the three alloys were almost the same. Matrix precipitates were GPII zone and η' phase and possessed small size and dense distribution while grain boundary precipitates exhibited discontinuous distribution. The rank of strength and fracture toughness for the three alloys are SG>MG>LG. Tearing ridges had been found on all the fracture surface while only LG alloy possess obvious dimple characteristics. The a-N curve showed that crack length list is MG>LG >SG under a same cycle number. The da/dN-ΔK curve also proved that fatigue crack propagation (FCP) rate of MG alloy is slightly larger than that of LG alloy, both were apparently larger than that of SG alloy. The width of fatigue striations on FCP fracture surface also backed it. Besides, obvious transgranular cracking characteristics and apparent secondary cracks were found on the FCP fracture surface.
Recent Thymic Emigrants Require RBPJ-Dependent Notch Signaling to Transition into Functionally Mature Naive T Cells
Authors: Teichman Sintia , Wang Helen , Lee Christina R , Mohtashami Mahmood , Foerster Elisabeth , Han Jianxun , Trotman-Grant Ashton C , Winer Shawn , Tsui Hubert , Philpott Dana J , Zúñiga-Pflücker Juan Carlos
Published: May 2023

Recent thymic emigrant (RTE) cells are nascent T cells that continue their post-thymic maturation in the periphery and dominate T cell immune responses in early life and in adults having undergone lymphodepletion regimens. However, the events that govern their maturation and their functionality as they transition to mature naive T cells have not been clearly defined. Using RBPJind mice, we were able to identify different stages of RTE maturation and interrogate their immune function using a T cell transfer model of colitis. As CD45RBlo RTE cells mature, they transition through a CD45RBint immature naive T (INT) cell population that is more immunocompetent but shows a bias toward IL-17 production at the expense of IFN-γ. Additionally, the levels of IFN-γ and IL-17 produced in INT cells are highly dependent on whether Notch signals are received during INT cell maturation or during their effector function. IL-17 production by INT cells showed a total requirement for Notch signaling. Loss of Notch signaling at any stage of INT cells resulted in an impaired colitogenic effect of INT cells. RNA sequencing of INT cells that had matured in the absence of Notch signals showed a reduced inflammatory profile compared with Notch-responsive INT cells. Overall, we have elucidated a previously unknown INT cell stage, revealed its intrinsic bias toward IL-17 production, and demonstrated a role for Notch signaling in INT cell peripheral maturation and effector function in the context of a T cell transfer model of colitis.
Idiopathic inflammatory myopathies linked to vaccination against SARS-CoV-2: a systematic review
Authors: Camargo-Coronel A. , Quiñones-Moya H. , Hernández-Zavala M.R. , Hernández-Vázquez J.R. , Vázquez-Zaragoza M.Á.
Published: May 2023

The COVID-19 pandemic represents a global health problem, which has been mitigated by the opportune introduction of vaccination programs. Although we already know the benefit that vaccines provide, these are not exempt from adverse events which can be mild to deadly, such as idiopathic inflammatory myopathies, in which a temporal association has not been defined. It is for this reason that we carried out a systematic review of all reported cases of vaccination against COVID-19 and myositis. To identify previously reported cases of idiopathic inflammatory myopathies associated with vaccination against SARS-CoV-2 we registered this protocol on the website of PROSPERO with identification number CRD42022355551. Of the 63 publications identified in MEDLINE and 117 in Scopus, 21 studies were included, reporting 31 cases of patients with vaccination-associated myositis. Most of these cases were women (61.3%); mean age was 52.3 years (range 19-76 years) and mean time of symptom onset post-vaccination was 6.8 days. More than half of the cases were associated with Comirnaty, 11 cases (35.5%) were classified as dermatomyositis, and 9 (29%) as amyopathic dermatomyositis. In 6 (19.3%) patients another probable trigger was identified. Case reports of inflammatory myopathies associated with vaccination have heterogeneous presentations without any specific characteristics: as a consequence, it is not possible to ensure a temporal association between vaccination and the development of inflammatory myopathies. Large epidemiological studies are required to determine the existence of a causal association.
Post-streptococcal scleredema an unusual rare mimicker of scleroderma: a case report
Authors: Gorial F.I. , Awadh N.I. , Al-Obaidi A.D. , Al-Obaidi M.N. , Hashim H.T. , Hasan H.J.
Published: May 2023

cleredema of Buschke is a rare pathological disorder of connective tissue, which is characterized by a woody, diffuse induration of the skin, most often in the upper extremities. We report an extremely rare complication of post-streptococcal infection in a six-year-old male complaining of gradually progressing, painless skin thickening and tightness which was preceded by a one-month history of fever, cough, and tonsillitis. By reporting this case, we hope to contribute to the creation of a database for future research aimed at better understanding the incidence, pathophysiology, and management of this extremely rare complication.
Secukinumab retention rate is greater in patients with psoriatic arthritis presenting with axial involvement
Authors: Adami G. , Idolazzi L. , Benini C. , Fracassi E. , Carletto A. , Viapiana O. , Gatti D. , Rossini M. , Fassio A.
Published: May 2023

Psoriatic arthritis (PsA) is an inflammatory disease characterized by peripheral and axial involvement. Biological disease-modifying antirheumatic drugs (bDMARDs) are the mainstream treatment for PsA and bDMARDs retention rate is a proxy for the drug’s overall effectiveness. However, it is unclear whether IL-17 inhibitors can have a higher retention rate than tumor necrosis factor (TNF) inhibitors, in particular in axial or peripheral PsA. A real-life observational study was conducted on bDMARD naïve PsA patients initiating TNF inhibitors or secukinumab. Time-to-switch analysis was carried out with Kaplan-Meyer curves (log-rank test) truncated at 3 years (1095 days). Sub-analyses of Kaplan-Meyer curves between patients presenting with prevalent peripheral PsA or prevalent axial PsA were also conducted. Cox regression models were employed to describe predictors of treatment switch/swap. Data on 269 patients with PsA naïve to bDMARD starting either TNF inhibitors (n=220) or secukinumab (n=48) were retrieved. The overall treatment retention at 1 and 2 years was similar for secukinumab and TNF inhibitors (log-rank test p NS). We found a trend towards significance in the Kaplan-Meyer at 3 years in favor of secukinumab (log-rank test p 0.081). Predominant axial disease was significantly associated with a higher chance of drug survival in secukinumab users (adjusted hazard ratio 0.15, 95% confidence interval = 0.04-0.54) but not in TNF inhibitor users. In this real-life, single-center, study on bDMARD naïve PsA patients, axial involvement was associated with longer survival of secukinumab but not of TNF inhibitors. Drug retention of secukinumab and TNF inhibitors were similar in predominantly peripheral PsA.
Personal Projects Analysis as an idiographic approach in psychotherapy: an exploratory study
Authors: Pedroso de Lima Margarida , Albuquerque Isabel , Martins Paulo Jorge , Gonzalez António-José
Published: May 2023

Client feedback research is a new but encouraging area that recognizes the importance of engaging patients in offered treatments and the relevance of the relationship between therapist and client. This study aimed to explore clients’ experiences of goal-oriented work using Personal Projects Analysis (PPA). PPA was applied to 5 participants of a psychodrama group after their consent and in agreement with the ethics and deontology research university committee. Their progress was evaluated with Clinical Outcomes in Routine Evaluation Outcome Measure (CORE-OM; 4 moments) and subjective well-being measures. Findings show how personal projects may be informative about clients’ difficulties and change processes. All outcomes on CORE-OM went below clinical cut-off points, and all these changes are reliable and clinically significant. PPA offers a consistent way to implement the goals approach in a psychotherapeutic context successfully. Nevertheless, some adjustments need to be implemented in the goal-oriented work using PPA.
Stressful Major Life Events and Chronic Urticaria
Authors: Choudhari Preeti Ganesh , Hundi Ganesh Kamath , Sukumar D
Published: May 2023

Background:

The skin and central nervous system are derivatives of embryonic ectoderm. There is an etiological factor of stressful life events in various skin diseases such as chronic urticaria through psychosomatic mechanisms. Many observations and case series are reported in favor of this opinion.

Objectives:

To evaluate the stressful life events within one year, six months and a month preceding onset or exacerbation of lesions in chronic idiopathic urticaria cases enrolled in this study.

Material and Methods:

It is an Observational descriptive questionnaire-based study, which included minimum of 50 patients of chronic idiopathic urticaria and important stressful events were noted in these subjects using Gurmeet Singh's presumptive stressful life events (PSLE) scale.

Results:

Out of 50 cases, stressful life events preceded the exacerbation of the chronic urticaria in 16 (32%) patients. Amongst them 12 (24%) showed slight degree and four (8%) showed moderate degree of stress and none of the cases reported great degree of stress. Among 16 cases, eight (50%) cases noticed exacerbation within six months of experiencing stressful life event with higher degree of severity in older age group (p = 0.004). Financial loss or problem was the most common stressful life event seen in four out of 16 cases (25%) (p = 0.000). Few desirable events were also found as stressors in four cases accounting for 25%.

Conclusion:

These results support association between psychological factors and exacerbation of the disease. The need for stress management programs in high stress scores to cope up with the stressful events, will further help in reducing the morbidity.
Single Plaque Lepromatous Leprosy Presenting as Granuloma Annulare
Authors: Chintagunta Sudha Rani , Jaju Priyanka
Published: May 2023

Leprosy is a chronic infectious disease caused by Mycobacterium leprae, primarily affecting the peripheral nerves and skin. The clinical presentation of leprosy is highly variable, depending on the immune status of the individual. Based on the Ridley–Jopling classification, the clinical spectrum ranges from tuberculoid to lepromatous leprosy (LL). In all its stages, it can mimic various other conditions. Early and accurate diagnosis of leprosy is crucial because late recognition may give rise to permanent deformity resulting from the disease. Here, we report a case of LL clinically presenting as granuloma annulare in a 75-year-old man, which was diagnosed and confirmed by histopathology.
Importance of Dermoscopy in Differentiating Common Urticaria and Urticarial Vasculitis
Authors: Madarkar Mahajabeen Saheb Patel
Published: May 2023

Background:

Urticarial vasculitis is a clinicopathological entity that overlaps with common urticaria, and histopathological diagnosis is required for differentiation between them.

Objectives:

To determine, for the first time, if skin surface microscopy can aid in the clinical differentiation between common urticaria and urticarial vasculitis in daily practice. Materials and Methods: Lesions in 20 patients with a clinical diagnosis of urticaria were studied. All urticarial lesions were subjected to dermoscopy, skin biopsy, and histopathological examination to confirm the diagnosis. Dermoscopy was performed using Derm Lite 3 dermoscope and images captured were anyalysed. Clinical images were taken. A punch biopsy was performed in all patients. Statistical analysis was done. Results: In 11 patients diagnosed clinically as chronic urticaria, on dermoscopy showed red lines in 9(45%), red dots in 2 (10%) and structureless areas in 8(40%) patients. In 9 patients diagnosed as urticarial vasculitis clinically, on dermoscopy revealed purpuric dots in 8(40%) and purpuric globules in 5(25%) patients.

Conclusion:

We conclude that in our setting dermoscopy significantly facilitates the detection, diagnosis and differentiation of common urticaria and urticarial vasculitis.
A Case Series of Disseminated Porokeratosis
Authors: Logeshwari J , A Patel Nippa Devi , Varala Sirisha , Krishna Ananthula Venkata
Published: May 2023

Porokeratosis is an autosomal dominant disorder of epidermal keratinization resulting from abnormal expansion of latent clones following chronic ultraviolet exposure or immunosuppression. Various clinical and morphological variants of porokeratosis are present, among which disseminated superficial actinic porokeratosis (DSAP) is the most common subtype located predominantly on the sun exposed areas, whereas disseminated superficial porokeratosis (DSP) is present both on the sun exposed and sun protected areas including oral mucosa and genitalia. Porokeratosis is characterized clinically by annular plaques with atrophic center and thready border and histologically by the presence of cornoid lamella. DSAP may be missed because of its inconspicuous nature in dark skinned individuals and may sometimes be mistaken for actinic keratoses in sun-damaged skin. Here, we report a case series of five patients with disseminated porokeratosis with varied presentations.
Cobblestone Appearances in Dermatology
Authors: Tiwary Anup Kumar , Kumar Piyush
Published: May 2023

Dermatology is a visual medical discipline which demands watchful eyes, profound knowledge of different morphologic patterns of various dermatoses, and extensive clinical experience. A meticulous cutaneous examination always helps in generating the close differential diagnoses and incorporation of past visual experience leads to a provisional diagnosis, obviating the need of further investigations in many cases. Although there is a wide spectrum of morphologic presentations, some dermatoses may have characteristic appearances such as cobblestoning, Peau d' orange, umbilication, and Christmas-tree pattern. Identification of these lesional characteristics or patterns can efficiently avoid the misdiagnosis and unnecessary diagnostic workup. In this article, skin diseases showing cobblestone appearances on both clinical and dermoscopic examination have been compiled and outlined in brief.