bluuebunny/crossref_metadata_2025 huggingface dataset:
A Value-added COSMOS2020 Catalog of Physical Properties: Constraining Temperature-dependent Initial Mass Function
Authors: Rusakov Vadim , Steinhardt Charles L. , Sneppen Albert
Published: August 2023

This work presents and releases a catalog of new photometrically derived physical properties for the ∼105 most well-measured galaxies in the COSMOS field on the sky. Using a recently developed technique, spectral energy distributions are modeled assuming a stellar initial mass function (IMF) that depends on the temperature of gas in star-forming regions. The method is applied to the largest current sample of high-quality panchromatic photometry, the COSMOS2020 catalog, that allows for testing this assumption. It is found that the galaxies exhibit a continuum of IMF and gas temperatures, most of which are bottom-lighter than measured in the Milky Way. As a consequence, the stellar masses and star formation rates of most galaxies here are found to be lower than those measured by traditional techniques in the COSMOS2020 catalog by factors of ∼1.6–3.5 and 2.5–70.0, respectively, with the change being the strongest for the most active galaxies. The resulting physical properties provide new insights into variation of the IMF-derived gas temperature along the star-forming main sequence and at quiescence, produce a sharp and coherent picture of downsizing, as seen from the stellar mass functions, and hint at a possible high-temperature and high-density stage of early galactic evolution.
The Minimum Variation Timescales of X-Ray Bursts from SGR J1935+2154
Authors: Xiao Shuo , Yang Jiao-Jiao , Luo Xi-Hong , Xiong Shao-Lin , Qu Yuan-Hong , Zhang Shuang-Nan , Xue Wang-Chen , Li Xiao-Bo , Tuo You-Li , Dong Ai-Jun , Zhao Ru-Shuang , Dang Shi-Jun , Shang Lun-Hua , Ma Qing-Bo , Cai Ce , Wang Jin , Wang Ping , Li Cheng-Kui , Yi Shu-Xu , Zhang Zhen , Ge Ming-Yu , Zheng Shi-Jie , Song Li-Ming , Peng Wen-Xi , Wen Xiang-Yang , Li Xin-Qiao , An Zheng-Hua , Xu Xin , Wang Yue , Zheng Chao , Zhang Yan-Qiu , Liu Jia-Cong , Zhang Bin , Xie Wei , Feng Jian-Chao , Wang De-Hua , Zhi Qi-Jun
Published: August 2023

The minimum variation timescale (MVT) of soft gamma-ray repeaters can be an important probe to estimate the emission region in pulsar-like models, as well as the Lorentz factor and radius of the possible relativistic jet in gamma-ray burst (GRB)–like models, thus revealing their progenitors and physical mechanisms. In this work, we systematically study the MVTs of hundreds of X-ray bursts (XRBs) from SGR J1935+2154 observed by Insight-HXMT, GECAM, and Fermi/Gamma-ray Burst Monitor from 2014 July to 2022 January through the Bayesian block algorithm. We find that the MVTs peak at ∼2 ms, corresponding to a light-travel time size of about 600 km, which supports the magnetospheric origin in pulsar-like models. The shock radius and the Lorentz factor of the jet are also constrained in GRB-like models. Interestingly, the MVT of the XRB associated with FRB 200428 is ∼70 ms, which is longer than that of most bursts and implies its special radiation mechanism. In addition, the median of MVTs is 7 ms, shorter than the median MVTs of 40 ms and 480 ms for short GRBs or long GRBs, respectively. However, the MVT is independent of duration, similar to GRBs. Finally, we investigate the energy dependence of MVT and suggest that there is a marginal evidence for a power-law relationship like GRBs, but the rate of variation is at least about an order of magnitude smaller. These features may provide an approach to identify bursts with a magnetar origin.
Confirmation of Subsolar Metallicity for WASP-77Ab from JWST Thermal Emission Spectroscopy
Authors: August Prune C. , Bean Jacob L. , Zhang Michael , Lunine Jonathan , Xue Qiao , Line Michael , Smith Peter C. B.
Published: August 2023

We present the dayside thermal emission spectrum of WASP-77Ab from 2.8 to 5.2 μm as observed with the NIRSpec instrument on the James Webb Space Telescope (JWST). WASP-77Ab was previously found to have a subsolar metallicity and a solar carbon-to-oxygen (C/O) ratio from H2O and CO absorption lines detected using high-resolution spectroscopy. By performing atmospheric retrievals on the JWST spectrum assuming chemical equilibrium, we find a subsolar metallicity [M/H] =

−

0.91

−
0.16

+
0.24

and C/O ratio

0.36

−
0.09

+
0.10

. We identify H2O and CO and constrain their abundances, and we find no CO2 in the spectrum. The JWST and high-resolution spectroscopy results agree within ∼1σ for the metallicity and within 1.8σ for the C/O ratio. However, our results fit less well in the picture painted by the shorter wavelength spectrum measured by Hubble Space Telescope Wide Field Camera 3. Comparing the JWST thermal emission spectra of WASP-77Ab and HD 149026b shows that both hot Jupiters have nearly identical brightness temperatures in the near-infrared but distinctly different atmospheric compositions. Our results reaffirm high-resolution spectroscopy as a powerful and reliable method to measure molecular abundances. Our results also highlight the incredible diversity of hot Jupiter atmospheric compositions.
Deuterium Escape on Photoevaporating Sub-Neptunes
Authors: Gu Pin-Gao , Chen Howard
Published: August 2023

We investigate the evolution of the deuterium-to-hydrogen (D/H) mass ratio driven by EUV photoevaporation of hydrogen-rich atmospheres of close-in sub-Neptunes around solar-type stars. For the first time, the diffusion-limited approach in conjunction with energy-limited photoevaporation is considered in evaluating deuterium escape from evolving exoplanet H/He envelopes. We find that the planets with smaller initial gas envelopes and thus smaller sizes can lead to weaker atmospheric escape, which facilitates hydrogen–deuterium fractionation. Specifically, in our grid of simulations with a low envelope mass fraction of less than 0.005, a low-mass sub-Neptune (4–5 M
⊕) at about 0.25–0.4 au or a high-mass sub-Neptune (10–15 M
⊕) at about 0.1–0.25 au can increase the D/H values by greater than 20% over 7.5 Gyr. Akin to the helium-enhanced envelopes of sub-Neptunes due to photoevaporating escape, the planets along the upper boundary of the radius valley are the best targets to detect high D/H ratios. The ratio can rise by a factor of ≲1.65 within 7.5 Gyr in our grid of evolutionary calculations. The D/H ratio is expected to be higher in thinner envelopes as long as the planets do not become bare rocky cores.
Review and Revision of the Lunar Cratering Chronology—Lunar Timescale Part 2
Authors: Werner Stephanie C. , Bultel Benjamin , Rolf Tobias
Published: August 2023

Times and rates of planetary surface-modifying processes are crucial for the sequence and correlation of events on planetary bodies. For most planetary surfaces, superposition principles and crater densities are commonly used methods to collect relative age information. Lunar-based cratering-chronology models, which pair crater densities and sample ages from several lunar landing and sampling sites, calibrate the relative age information in absolute time. Here, we propose calibration pairs based on new crater statistics and spectrally supported sample-age assignments for the lunar cratering-chronology model. The resulting model reflects modern high-precision, radiometric ages, compositional and spectral information, and an up-to-date crater-production function. This revision supports a crater-forming projectile flux with monotonic decay, similar to previous standard models, but of distinctively lower flux. This originates from lower crater densities identified in spectrally and morphologically defined reference units, and from assigning more precise sample ages accounting for spectral resemblance between reference unit and sample. The observed maximal values for crater densities and ages provide the oldest and most densely cratered calibration pair. Because of the nature of highland samples, age constraints for the Luna 20 and Apollo 16 sampling sites remain challenging, which restricts the confidence in times for individual basin-formation events older than Orientale Basin. The new cratering-chronology model, when transferred to other planetary bodies, would cause aging of the surfaces, because of the lower overall flux.
Improving Marine Megafauna Knowledge with eDNA: A French Story
Authors: Haderlé Rachel , Valentini Alice , Ung Visotheary , Jung Jean-Luc
Published: August 2023

In the current context of large-scale biodiversity loss (Díaz et al. 2019), it is urgent to carry out biodiversity inventories in order to investigate spatial and temporal variations. Among the available methods, environmental DNA (eDNA) (Taberlet et al. 2018) combined with molecular metabarcoding (Valentini et al. 2009) bring new insights in drafting inventories of taxa present in an environment.

Approaches based on eDNA facilitate the study of remote ecosystems and the detection of rare, cryptic or invasive species in a non-invasive way (Bohmann et al. 2014). In the marine realm, the study of mobile fauna, including mammals particularly, can greatly benefit from these new techniques.

Here, we present a case study carried out in the northeast and northwest Atlantic, within the boundaries of marine protected areas. The Iroise Natural Marine Park*1 was the first French marine natural park created in France in 2007 (Fig. 1). The first campaign in the Iroise Natural Marine Park successfully detected several species of cetacean (e.g., Lagenorhynchus albirostris, Lagenorhynchus obliquidens) and four species of elasmobranchs (e.g., Scyliorhinus canicula, Torpedo marmorata, Raja undulata and Mustelus asterias). This study was extended to the Martinique Natural Marine Park*2, where similar analyses identified three cetacean species (Stenella attenuata, Lagenodelphis hosei and Tursiops truncatus) and 193 teleost taxa (Riou 2022), representing more than half of the species expected in Martinique. The analyses carried out in Martinique highlighted several remarkable sites for fish biodiversity. In Guadeloupe, in the heart of the Agoa Marine Mammals Sanctuary*3 (corresponding to the French Antilles exclusive economic zone), the taxonomic composition of different eDNA samples made in 2021 and 2022 was compared. The samples were analyzed using different primer sets, specific to vertebrates, teleosts and mammals. Comparison of the results obtained with vertebrate-specific primers and those specific to teleosts showed complementary results. For cetaceans, the analyses distinguished ten distinct cetacean taxonomic units and at least 3 distinct species from four samples. In addition, the eDNA samples were used to discriminate between the two recently recognised bottlenose dolphin ecotypes, based on the observation of a fixed nucleotide difference on the barcode targeted by the mammal-specific primers. New primers are currently being developed to make it easier to distinguish species of Delphinidae, which are still complex to identify.

Environmental DNA and metabarcoding offer new possibilities for the inventories of marine megafauna and support adequate conservation decision-making processes. It is a major step towards better monitoring of marine mammal populations of the Atlantic Ocean. Moreover, our datasets will be freely available through open platforms following the FAIR (Findable, Accessible, Interoperable, and Reusable) principles.
Visualization design of health detection products based on human-computer interaction experience in intelligent decision support systems
Authors: Su Yinhua
Published: August 2023

In order to meet the needs of the human-computer interaction experience of health testing products and improve the decision-making efficiency of intelligent decision support systems, we visualized the design of health testing products. We summarized the design methods for the human-computer interaction experience of health testing products, analyzed health testing data visualization requirements in terms of thematic databases, data visualization diagrams, thematic dashboards and knowledge management systems, and introduced the general process of monitoring information visualization. The visual health testing product information display interface is designed to visualize the testing data in three aspects: information architecture, interaction mode and visual language presentation. The visual intelligent decision support system and the visual interface design are combined for the functional design of the visual intelligent decision support system. The experimental part of the study investigates the effectiveness of the visualized health testing product of the intelligent decision support system, using the questionnaire method and health data measurement method to collect results on the interactivity, convenience, health decision accuracy and product satisfaction of the health monitoring product, with the data presented as a percentage system. The experimental results show that the interactivity, convenience and health decision accuracy of the intelligent decision support visual health monitoring product are higher than those of traditional health monitoring products, with interactivity evaluation results above 85% and high satisfaction with product use, indicating that the product can provide new and innovative design ideas in home healthcare.
Cholesterol dependent cytolysins and the brain: Revealing a potential therapeutic avenue for bacterial meningitis
Authors: Pramitasuri Tjokorda Istri , Susilawathi Ni Made , Tarini Ni Made Adi , Sudewi AA Raka , Evans Matthew C
Published: August 2023

Bacterial meningitis is a catastrophic nervous system disorder with high mortality and wide range of morbidities. Some of the meningitis-causing bacteria occupy cholesterol dependent cytolysins (CDCs) to increase their pathogenicity and arrange immune-evasion strategy. Studies have observed that the relationship between CDCs and pathogenicity in these meningitides is complex and involves interactions between CDC, blood-brain barrier (BBB), glial cells and neurons. In BBB, these CDCs acts on capillary endothelium, tight junction (TJ) proteins and neurovascular unit (NVU). CDCs also observed to elicit intriguing effects on brain inflammation which involves microglia and astrocyte activations, along with neuronal damage as the end-point of pathological pathways in bacterial meningitis. As some studies mentioned potential advantage of CDC-targeted therapeutic mechanisms to combat CNS infections, it might be a fruitful avenue to deepen our understanding of CDC as a candidate for adjuvant therapy to combat bacterial meningitis.
Possible relationship between the gut leaky syndrome and musculoskeletal injuries: the important role of gut microbiota as indirect modulator
Authors: Álvarez-Herms Jesús , González Adriana , Corbi Francisco , Odriozola Iñaki , Odriozola Adrian
Published: August 2023

This article aims to examine the evidence on the relationship between gut microbiota (GM), leaky gut syndrome and musculoskeletal injuries. Musculoskeletal injuries can significantly impair athletic performance, overall health, and quality of life. Emerging evidence suggests that the state of the gut microbiota and the functional intestinal permeability may contribute to injury recovery. Since 2007, a growing field of research has supported the idea that GM exerts an essential role maintaining intestinal homeostasis and organic and systemic health. Leaky gut syndrome is an acquired condition where the intestinal permeability is impaired, and different bacteria and/or toxins enter in the bloodstream, thereby promoting systemic endotoxemia and chronic low-grade inflammation. This systemic condition could indirectly contribute to increased local musculoskeletal inflammation and chronificate injuries and pain, thereby reducing recovery-time and limiting sport performance. Different strategies, including a healthy diet and the intake of pre/probiotics, may contribute to improving and/or restoring gut health, thereby modulating both systemically as local inflammation and pain. Here, we sought to identify critical factors and potential strategies that could positively improve gut microbiota and intestinal health, and reduce the risk of musculoskeletal injuries and its recovery-time and pain. In conclusion, recent evidences indicate that improving gut health has indirect consequences on the musculoskeletal tissue homeostasis and recovery through the direct modulation of systemic inflammation, the immune response and the nociceptive pain.
La censure des textes en Iran après la révolution de 1979 : histoire et fonctionnement
Authors: Laetitia Nanquette
Published: August 2023

Cet article retrace l’histoire de la censure contemporaine des textes littéraires en Iran et explique le fonctionnement du système de censure après la révolution islamique. Il s’intéresse aux évolutions des politiques de publication et à l’impact exercé par la censure sur le champ littéraire iranien et dans la société iranienne en s’appuyant sur des exemples concrets.
New Concept of Power Generation from TEGs Using the Sun Irradiation and Oil Tanks – Thermal Modeling and Parametric Study
Authors: Faraj Jalal , El Achkar Georges , Abdulhay Bakri , Hicham El Hage , Taher Rani , Khaled Mahmoud
Published: August 2023

In this manuscript, a new concept of power generation from thermoelectric generators TEGs using the sun irradiation and two oil tanks, one hot and one cold, is proposed. It consists of two oil tanks separated by a plate covering several TEGs in series. The oil tank at the bottom of the system constitutes a cold convection condition for the TEGs plate; on the other hand, the upper oil tank accounts for a hot convection condition since its upper surface is transparent and therefore subjected to the sun irradiation that will heat up the oil. To test the feasibility of this concept, an appropriate thermal modeling is developed and associated parametric analysis was carried out. It shows that powers up to 242 W can be generated with a system having a hot oil tank height of 0.2 m along with a width and length of 2 m each.
Effect of In-Plane Stress on the Frictional Behavior of Thin Layers
Authors: Menga Nicola , Carbone Giuseppe
Published: August 2023

Usually, contact mechanics focus on semi-infinite solids, so that any interaction between normal and in-plane deformation is commonly disregarded. However, when dealing with layers of finite thickness, this assumption is no longer valid, and the specific geometry of the contact pair plays a key role in determining the normal-tangential coupling. In this study, we focus on the exemplar case of a thin deformable layer in frictional sliding contact with a rough profile, where the interplay between tangential friction and normal pressure may lead to significantly different contact behavior compared to the uncoupled case, both in terms of contact area size and frictional response.
Success story of ASNAC 2023
Authors: Fernando Sanjaya S. , Vithanage Kumarangie
Published: August 2023

No abstract available
Third nerve palsy – surgical or medical?
Authors: Gunatilake Saman B.
Published: August 2023

Ischaemic oculomotor nerve palsies (IONP) usually are pupil-sparing. Diabetes, hypertension, and atherosclerosis are commonly associated with IONP. Vasculopathic third nerve mononeuropathies are caused by extra-axial infarcts of the core of the third nerve, which derives its blood supply from the vasa nervorum. The pupillomotor fibers are spared because of their more peripheral location and blood supply from the pial vessels. The superficial location of the pupillomotor fibers renders them more susceptible to damage from compressive lesions, most commonly posterior communicating artery aneurysms. The rule of the pupil states that an isolated, atraumatic third nerve palsy with complete external ophthalmoplegia and a normal pupil has a greater than 90% probability of being due to microvascular ischaemia. However, there are exceptions and more importantly misinterpretation of the rule can lead to unnecessary investigations and complications. This review is an attempt to clarify what a pupil sparing oculomotor palsy is and when to investigate further for a compressive lesion such as an aneurysm.
The Lexical Features of Types of Linguistic Collocations: A Study with Special Reference to Selected Public Administration Circulars in Sinhala and Their English Translations
Authors: Malsha R. P. B. , Ariyaratne Manoj , Samaranayaka Chulananda
Published: August 2023

Language is designed to fulfil the communication requirements of communities. Each language has specific and unique characteristics in comparison to any other language. Collocation is also a vital concept that assists in enhancing the quality and formality of both written and spoken languages. The concept of collocation means a set of words that naturally or unintentionally co-occur together to deliver a particular meaning. The attention of many researchers and scholars has been drawn to this concept due to the absence of a recognized or fully accurate definition and classification in this regard. This study aimed at identifying the lexical features of the types of linguistic collocations used in Public Administration Circulars in Sinhala. The study focused on four linguistic collocations suggested by Li et al. (2005). Accordingly, lexical features such as word length, word frequency, high-frequency words, and low-frequency words were identified. The data were collected for the research after extensive analysis of circulars and then the specific sets of words and terms were extracted. Content analysis was used to analyze data. The results of the study indicate that the most frequently used type of linguistic collocation in Public Administration Circulars are fixed collocations. The highest word length of fixed and strong collocations belongs to the 3-letter word group and in loose collocations, the 4-letter word group represents the highest value. Furthermore, the word frequency of fully fixed collocations is equal for each word. The maximum word frequency of fixed collocations and strong collocations is 13, whereas the highest word frequency of loose collocations is 4.
The Role of Prebiotics and Probiotics as an Adjuvant Therapy in Children with Idiopathic Relapsing Nephrotic Syndrome: A Prospective Open-label Clinical Trial
Authors: Mohammed Rehab Ahmed , Hussein Sherin Khamis , Gaber Sylvana Nady , Ahmed  , Abonaga Fatma , Abdelfattah Walaa , Said Eman Sayed , Boushra Amy Fakhry
Published: August 2023

Idiopathic nephrotic syndrome (INS) is the most common cause of NS in children. It is characterized by the existence of edema, proteinuria, and hypoalbuminemia, as well as repeated relapses. The etiology remains unknown, but new evidence for its pathogenesis relates to the dysfunction of T-regulatory (T-reg) cells, which could be caused by dysbiosis of the gut microbiota. Our study aimed to investigate the effect of prebiotics and probiotics as adjuvant therapies for children with relapsing INS. The study was designed as a prospective open-label randomized clinical trial involving 30 children diagnosed with relapsing INS. The children were randomly divided into two groups. Group 1 was treated with prednisone only, and Group 2 was treated with prebiotics and probiotics in addition to prednisone. Fresh stool samples were collected from the children. Lactobacillus species were isolated and identified by conventional microbiological methods. The total number of Lactobacillus species was counted for each stool sample. The population of T-reg cells in the peripheral blood mononuclear cells was analyzed using flow cytometry. Children treated with prebiotics and probiotics in addition to steroids showed a significant increase in T-reg cells (CD4+/CD25+/FOXp3+) in the peripheral blood and a higher count of Lactobacillus species in their stool alongside a significant decrease in the rate of relapses in this group compared with Group 1. Treatment with prebiotics and probiotics signi-ficantly increased T-reg cells and decreased the rate of relapse in INS.
Quality of Life and Health-related Quality of Life in Patients with End-stage Kidney Disease Undergoing Hemodialysis: A Literature Review
Authors: Al-Rajhi Waleed , Al Salmi Issa
Published: August 2023

Measurements of quality are intended to drive improvements in care and provide accountability regarding costs and quality. Quality of life (QoL) and health-related QoL (HRQoL) comprise personal perceptions, health, and socioenvironmental dimensions. This structured integrative review aimed to present and analyze the nature and significance of the predictors of QoL and HRQoL in patients with end-stage kidney disease (ESKD). The articles found through searching the main databases were assessed for sample size, design, and methodological limitations. The revised Wilson–Cleary conceptual framework of HRQoL and the World Health Organization's definition of QoL guided this review. Forty-five articles were selected (36 were observational or cross-sectional studies; nine were prospective). These articles reported a range of factors related to QoL and HRQoL characterized as physical, mental, socioeconomic, biological, and symptomatic. Few studies considered spiritual beliefs and cultural beliefs. There was a lack of consistency in the use of measures of QoL and HRQoL in ESKD. The most validated measures of HRQoL and QoL identified were the Short-Form 36 v2, the QoL Index – Dialysis, the Hospital, Anxiety, and Depression Scale, the Fatigue Severity Scale, the Itch Scale, the Spiritual Well-being Scale, and the Schedule for the Evaluation of QoL – Direct Weighting. Most studies were conducted in developed countries, with only two from the Middle East. The possible measures of QoL and HRQoL are health status, disease-specific, symptom-specific, spiritual, and individualized QoL measures. This set of measures is expected to capture the patients' own perceptions concerning their QoL and HRQoL.
The Substance and Cultural Connotations of Treating Prior to Disease
Authors: Duan Yishan
Published: August 2023

The substance of treating prior to disease in Traditional Chinese Medicine expects to dissipate symptoms before the disease occurs and maintain health until centenarian. This concept is a collective reflection of the intrinsic awareness of suffering by Chinese people. Moreover, its cultural connotations involve emphasis on preparation for adversity in times of safety and taking anticipative measures.
Odontogenic Keratocyst of Maxilla Managed with Enucleation and Peripheral Ostectomy: A Case Report
Authors: Gupta Manish , Gupta Monica , Gupta Akanksha
Published: August 2023

Odontogenic keratocyst has many etiological classifications, variable nomenclature, and treatment dilemmas associated with it. We present the case of a young female with a large single painless and progressive lesion involving the right maxilla successfully treated with enucleation and peripheral ostectomy. The case is presented to highlight that these cysts are usually asymptomatic initially and may be confused with maxillary sinusitis. They need careful radiological and histopathological evaluation and should be resected using aggressive approaches to prevent future recurrences.
A Cross-Sectional Study on Visual Problems among Zari Artisans of North India
Authors: Garg Pragati , Raj Priyanka , Chellaiyan Vinoth Gnana , Singh Abhay
Published: August 2023

Background:

Working circumstances of the zardozi workers, it is highly likely that they develop visual problems that may range from simple asthenopic symptoms to severe visual disturbances. The present study was done to assess the visual problems existing today among zari artisans of North India.

Materials and Methods:

Two hundred and forty zari artisans were clinically examined during January 2022 to May 2022. All the patients were subjected to an ocular evaluation: Visual acuity, anterior segment evaluation, orthoptic evaluation with prism bars Goldmann Applanation tonometry, fundus examination, and refractive status of the patients. Means and proportions were calculated. The Chi-square test was applied. P < 0.05 is considered to be significant.

Results:

The mean age of the study population was 27 ± 12 years; majority of which were males, making up to 80.83% of the study population. Most of the subjects fell into the age group of 21–30 years. On testing the refractive error in them, we found 43.33% of the study subjects were hypermetropic, 35.00% were myopic, and 21.67% were emmetropic. Around 45% had poor convergence status while 26.67% had fatigue of convergence and 28.75% had fair convergence. A significant association was found between the positive fusional range and convergence status of the study subjects (P < 0.001).

Conclusion:

Adequate lighting conditions, proper ventilation and hygiene, short breaks in between, proper nutrition, correction of refractive error if any, and periodic regular eye checkup should be done to overcome these visual problems in Zardozi artisans.
Perception on Access to Health Care and Socioeconomic Impact of COVID-19 at Household Level in Rural Mandya, A Cross-Sectional Study in Southern Karnataka
Authors: Shashikantha S. K. , Sheethal M. P. , Huchchannavar Raghavendra
Published: August 2023

Background:

COVID-19 has affected the lives of millions around the globe. The social and economic impacts of COVID-19 are far more dangerous and will have far-reaching consequences on human lives. Hence, the present study was undertaken in a rural area to determine the impact of COVID-19 on socioeconomic status and their perception of access to health care.

Materials and Methods:

A community-based cross-sectional study was carried out for 2 months in March and April 2021 in rural Mandya, Karnataka. Adults aged above 18 years who consented were part of the study. The data obtained were entered into Microsoft Office excel sheet and analyzed using Epi info software.

Results:

There were 948 subjects in the study with a mean age of 49.59 ± 13.35 years. The family income decreased to 11201.53 ± 11315.243 Rs/month in COVID-19 period compared to 15354.75 ± 13523.079 Rs/month before COVID-19, because of the economic impacts of COVID-19 (Nearly 30% reduction, as mentioned by the respondents). More than 95% of the subjects had heard about COVID-19. Out of the total, 18% of the respondents visited a government health center, 12.55% visited a private health center for various health-related issues.

Conclusion:

A substantial proportion of our subjects reported income loss during COVID-19 crisis. A majority of the subjects were aware of COVID-19 and its symptoms, and most of them were satisfied with the quality of health-care delivery during the pandemic crisis. However, much needs to be done to make their life better and a holistic approach involving all the stakeholders is a must to do that.
Overdamped dynamics of a falling inextensible network: Existence of solutions
Authors: Telciyan Ayk , Vorotnikov Dmitry
Published: August 2023

We study the equations of overdamped motion of an inextensible triod with three fixed ends and a free junction under the action of gravity. The problem can be expressed as a system of PDEs that involves unknown Lagrange multipliers and non-standard boundary conditions related to the freely moving junction. It can also be formally interpreted as a gradient flow of the potential energy on a certain submanifold of the Otto–Wasserstein space of probability measures. We prove global existence of generalized solutions to this problem.
Liver transplant in primary sclerosing cholangitis: Current trends and future directions
Authors: Shah Yash R , Nombera-Aznaran Natalia , Guevara-Lazo David , Calderon-Martinez Ernesto , Tiwari Angad , Kanumilli SriLakshmiDevi , Shah Purva , Pinnam Bhanu Siva Mohan , Ali Hassam , Dahiya Dushyant Singh
Published: August 2023

Primary sclerosing cholangitis (PSC) is a chronic and progressive immune-mediated cholangiopathy causing biliary tree inflammation and scarring, leading to liver cirrhosis and end-stage liver disease. Diagnosis of PSC is challenging due to its nonspecific symptoms and overlap with other liver diseases. Despite the rising incidence of PSC, there is no proven medical therapy that can alter the natural history of the disease. While liver transplantation (LT) is the most effective approach for managing advanced liver disease caused by PSC, post-transplantation recurrence of PSC remains a challenge. Therefore, ongoing research aims to develop better therapies for PSC, and continued efforts are necessary to improve outcomes for patients with PSC. This article provides an overview of PSC’s pathogenesis, clinical presentation, and management options, including LT trends and future aspects. It also highlights the need for improved therapeutic options and ethical considerations in providing equitable access to LT for patients with PSC. Additionally, the impact of liver transplant on the quality of life and psychological outcomes of patients with PSC is discussed. Ongoing research into PSC’s pathogenesis and post-transplant recurrence is crucial for improved understanding of the disease and more effective treatment options.
Enabling Pupils to Conceive Part-Whole Relations of Numbers and Develop Number Sense: Year One of Primary Schools in Malaysia
Authors: Sinnakaudan Santi , Kuldas Seffetullah , Hashim Shahabuddin , Ghazali Munirah
Published: August 2023

This review examines reasons for Malaysian pupils' underperformance in solving mathematics problems that demand numerical estimation and mental computation. Their underdeveloped number sense appears to be the major reason. According to the Ministry of Education, the national mathematics curriculum is unlikely to account for this underachievement. By contrast, this article argues that the curriculum largely focusing on written computation skills, is likely to account for the underperformance, given that the development of number sense has yet to become the focus of attention. This review further suggests teaching and learning activities that may enable the Malaysian pupils, in year one of primary schools, to conceive part-whole relations of numbers and thus develop number sense. The earlier they understand the part-whole relationship, the stronger they may develop number sense and thus the better can be their performance.
Conjecturing, generalizing and justifying: Building theory around teacher knowledge of proving
Authors: Lesseig Kristin
Published: August 2023

The purpose of this study was to detail teachers' proving activity and contribute to a framework of Mathematical Knowledge for Teaching Proof (MKT for Proof). While working to justify claims about sums of consecutive numbers, teachers searched for key ideas and productively used examples to make, test and refine conjectures. Analysis of teachers' mathematical activity revealed knowledge of the proving process that would be useful for and useable in the teaching of proof. This includes knowledge of the interconnections among empirical exploration, conjecturing, generalizing, and justifying as well as an understanding of the characteristics of examples and conjectures that could support the proving process. The central premise of this paper is that delineating aspects of teacher knowledge is a first step to supporting teachers' efforts to engage all students in fundamental mathematical practices of conjecturing, generalizing and justifying.
Measurement Approach to Teaching Fractions: A Design Experiment in a Pre-service Course for Elementary Teachers
Authors: Bobos Georgeana , Sierpinska Anna
Published: August 2023

In this paper, we present a design experiment in a "Teaching Mathematics"course for prospective elementary teachers where we sought to develop a measurement approach to fractions. We focus on the conceptualization of the mathematical content of the approach. We attribute our progress in the conceptualization to our efforts to overcome the challenges we had to face in bringing our students - prospective teachers - to thinking about fractions in a theoretical way. We describe some of these challenges in the paper. The approach was inspired by an approach under the same name, but addressed to children, developed by the psychologist V.V. Davydov and described in the paper by Davydov and Tsvetkovich (1991). Davydov's measurement approach proposes that, in order to develop a concept of fraction with sources in reality, children's attention should be directed to multiplicative relationships between quantities defined in terms of concrete units (such as kilos, inches or cups) rather than to indeterminate objects such as pizzas or cakes. Our original contribution is a systemic study of these relationships and operations on them, as a theoretical system, using definitions derived from measurement situations, mathematical reasoning based on these definitions and generalizations of observed patterns. It is intended to support a gradual process of abstraction of the notion of fraction as an abstract number that represents a measure of the relationship between two quantities. Furthermore, our proposal for conceptualizing fractions in this way is addressed to teachers, not to children. By its focus on relational reasoning about quantities and gradual construction of a theoretical system, the approach both requires and is expected to foster the development of quantitative reasoning and theoretical thinking.
How the Relational Paradigm Can Transform the Teaching and Learning of Mathematics: Experiment in Quebec
Authors: Polotskaia Elena
Published: August 2023

The main goal of this paper is to show how Vasily Davydov's powerful ideas about the nature of mathematical thinking and learning can transform the teaching and learning of additive word problem solving. The name Vasily Davydov is well known in the field of mathematics education in Russia. However, the transformative value of Davydov's theoretical work in this field has not yet been fully recognized by the larger international community. In this article, I use Davydov's vision of mathematics as the study of quantitative relationships - the vision underlying the relational paradigm in teaching and learning of mathematics. I use the example of one research project to demonstrate how the relational paradigm changes and reforms teaching practices. I discuss the teaching approach, developed within this paradigm, as well as the learning outcomes demonstrating the transformative power of Davydov's ideas.
Secondary School Students' Conception of Quadratic Equations with One Unknown
Authors: Didis Kabar Makbule Gozde
Published: August 2023

In recent years, quadratic equations have started to become of greater interest to researchers. This study explored what conceptions high school students have about quadratic equations with one unknown using concept definition and concept images as theoretical concept. The data was gathered through semi-structured interviews with 14 eleventh grade high school students. Analysis of data displayed that students could not provide a proper definition of quadratic equations with one unknown, and their definitions were not consistent with the formal (standard) definition of quadratic equations. Moreover, the findings showed that students' concept image of quadratic equation is quite limited and dominated by ideas factoring. Students' conception of quadratic equations also showed that participating students lacked three types of prerequisite knowledge, degree of polynomial, variable and equals sign. To enrich students' concept images both procedurally and conceptually, this study has implications for teachers. The implications of the findings are discussed.
The Development of Secondary Mathematics Teachers' Pedagogical Identities in the Social Context of Classroom Interactions
Authors: Kim Hyung Won
Published: August 2023

Research demonstrates a disjuncture between the practices encouraged by teacher education programs and what teachers actually do in the classroom. It also informs us that the cognitive and social characteristics of individual teachers such as their attitudes, beliefs and knowledge contribute to their classroom practices. This qualitative study investigates how the teacher identity of mathematics teachers - the person's sense of who he/she is as a mathematics teacher - is related to the disjuncture between encouraged and actual classroom practices. Specifically, the study looks into how mathematics teachers form their teaching practices in the social context of their classroom interactions, and tries to understand the nature of the discomfort that teachers sometimes experience in the process of shaping their classroom role and teaching practices. The study takes a dialogical approach to identity, seeing the self as something that an individual develops through interactions between his or her core "substantial self" and context-dependent "situational selves." The qualitative data were collected from four in-service high school teachers in the United States. The study sheds light on the variability of the process of shaping teaching practices; it discusses factors in this variability, and explores how teachers develop and settle into their practices through negotiation between the substantial self and situational selves in the classroom context.
Understanding Students' Computational Fluency: Synechistically Using Test Scores and Interviews for a Richer Picture
Authors: Shumway Jessica F. , Jordan Kerry E.
Published: August 2023

Mathematics education researchers are tasked with solving practical research problems involving complex constructs in complex settings. The effective integration of quantitative and qualitative data allows researchers to draw more nuanced conclusions about these complex phenomena. This article describes the use of a convergent parallel mixed methods design to integrate two seemingly conflicting data sources that measured six second-grade students' development of computational fluency. The mixed methods analysis of students' computational fluency assessments and interviews showed that there was variation in students' assessment scores, strategy use, and engagement of number sense. Within these variations, the quantitative and qualitative data converged or diverged at various measurement points, and the results highlight the importance of merging the two data sets to capture a richer picture of students' computational fluency. Implications for using mixed methods in understanding how mathematics learning occurs in classrooms are discussed.
Acquiring Math: Connecting Math Learning and Second Language Acquisition
Authors: Bosse Michael J. , Ringler Marjorie , Bayaga Anass , Fountain Catherine , Slate Young Erica
Published: August 2023

Research in second language acquisition and the learning of mathematics has matured through long, albeit disconnected, histories. This study examines how theories and models of second language acquisition can be applied to the learning of mathematics. Herein we investigate the intersection of second language acquisition theories and hierarchical models of mathematical learning and mastery. This comparison and analysis of seemingly disparate fields of study allows us to develop of a novel framework that helps to better define mathematical learning.
Describing Lesson Study Designed for Improvement of Mathematics Teachers' Knowledge of Student Thinking
Authors: ÖZALTUN ÇELİK Aytuğ , BUKOVA GÜZEL Esra
Published: August 2023

The aim of this study is to explain the process of lesson study designed for improving the mathematics teachers' knowledge of student thinking and to examine its effectiveness in terms of the teaching process and the teachers' professional development. The lesson study composed of three cycles was carried out with three mathematics teachers. Each cycle comprised of five stages. The data were collected from the interviews, the lesson observations, the field notes and the reflective diaries. The interviews were conducted with teachers, the teachers' lessons were observed by the researchers, the field notes were taken by the researchers and the reflective diaries were written by the teachers after each cycles. The data were examined by considering knowledge of student thinking in a detailed way. The teachers' awareness of knowledge of student thinking got increased by means of the lesson study model. They came to consider the students' thinking in their lessons and to question the underlying reasons of their ideas.
Conceptions of Expressions and Equations in Early Algebra: A Learning Trajectory
Authors: Moss Diana L , Lamberg Teruni
Published: August 2023

This article describes a learning trajectory on expressions and equations based on the sixth grade Common Core Mathematics Standards (NGA/CCSSO, 2010). A classroom teaching experiment using design research (Author, 2009) was conducted. A conjectured hypothetical learning trajectory (Simon, 1995; Clements & Sarama, 2004) was developed based on a review of research. The tasks were adapted and modified during the teaching experiment based on student sense making to support student learning. The realized trajectory that emerged and the design decisions that were made were documented. The data was analyzed using Corbin and Strauss' (2008) Constant Comparative method and Creswell's (2007) data analysis spiral. The findings reveal that student understanding of the changing meaning of variables within a problem context played a central role in student development of conceptual understanding of expressions and equations. Implications for classroom instruction and curriculum development are discussed.
Using Distributed Autonomous Adaptive Cruise Control Vehicles to
Mitigate Congestion in a Two-Lane Traffic Flow
Authors: Kurishige Masahiko
Published: August 2023

Steady advances in autonomous vehicle development are expected to lead to
improved traffic flow in terms of string stability compared with that for
human-driven vehicles. Fluctuation in intervehicle distances among a group of
vehicles without string stability is amplified as it propagates upstream
(rearward), which may cause traffic congestion. Since it will take a few decades
for autonomous vehicles to replace all human-driven vehicles, it is important to
tackle the problem of traffic congestion in a mixed flow of human-driven and
autonomous vehicles. Communication technologies such as fifth-generation mobile
communication systems, which are improving rapidly, enable vehicle-to-vehicle
communication with a sufficiently small delay. We previously reported a strategy
based on vehicle-to-vehicle communication for avoiding traffic congestion by
using leader–follower control, which is a distributed autonomous control
strategy. However, it was designed and evaluated for single-lane traffic. With
substantial multilane traffic, congestion triggered by changes in vehicle
velocity could appear more frequently and severely compared with that of
single-lane traffic due to vehicles cutting in from other lanes. Use of our
previously proposed strategy in this scenario could result in undesirable
repetitive deceleration of the distributed autonomous adaptive cruise control
(ACC) vehicles due to reduced spacing between a distributed autonomous ACC
vehicle and the preceding human-driven vehicle. Here, we report a distributed
autonomous ACC vehicle control strategy that prevents undesirable repetitive
deceleration while satisfying the string stability condition. With the proposed
control strategy, the reference acceleration is calculated as the weighted
average of two control functions. One function is used to achieve string
stability between two autonomous ACC vehicles, and the other is used to maintain
a safe distance between an autonomous ACC vehicle and the preceding standard
vehicle. We derive the condition for string stability of distributed
autonomously controlled ACC vehicles and demonstrate the validity of the
proposed control strategy using simulation.