bluuebunny/crossref_metadata_2025 huggingface dataset:
Going through changes – the role of autophagy during reprogramming and differentiation
Authors: Petersen Morten , Ebstrup Elise , Rodriguez Eleazar
Published: February 2024

Somatic cell reprogramming is a complex feature that allows differentiated cells to undergo fate changes into different cell types. This process, which is conserved between plants and animals, is often achieved via dedifferentiation into pluripotent stem cells, which have the ability to generate all other types of cells and tissues of a given organism. Cellular reprogramming is thus a complex process that requires extensive modification at the epigenetic and transcriptional level, unlocking cellular programs that allow cells to acquire pluripotency. In addition to alterations in the gene expression profile, cellular reprogramming requires rearrangement of the proteome, organelles and metabolism, but these changes are comparatively less studied. In this context, autophagy, a cellular catabolic process that participates in the recycling of intracellular constituents, has the capacity to affect different aspects of cellular reprogramming, including the removal of protein signatures that might hamper reprogramming, mitophagy associated with metabolic reprogramming, and the supply of energy and metabolic building blocks to cells that undergo fate changes. In this Review, we discuss advances in our understanding of the role of autophagy during cellular reprogramming by drawing comparisons between plant and animal studies, as well as highlighting aspects of the topic that warrant further research.
Blood oxygen transport and depletion in diving emperor penguins
Authors: Ponganis Paul J. , Williams Cassondra L. , Kendall-Bar Jessica M.
Published: February 2024

Oxygen store management underlies dive performance and is dependent on the slow heart rate and peripheral vasoconstriction of the dive response to control tissue blood flow and oxygen uptake. Prior research has revealed two major patterns of muscle myoglobin saturation profiles during dives of emperor penguins. In Type A profiles, myoglobin desaturated rapidly, consistent with minimal muscle blood flow and low tissue oxygen uptake. Type B profiles, with fluctuating and slower declines in myoglobin saturation, were consistent with variable tissue blood flow patterns and tissue oxygen uptake during dives. We examined arterial and venous blood oxygen profiles to evaluate blood oxygen extraction and found two primary patterns of venous hemoglobin desaturation that complemented corresponding myoglobin saturation profiles. Type A venous profiles had a hemoglobin saturation that (a) increased/plateaued for most of a dive's duration, (b) only declined during the latter stages of ascent, and (c) often became arterialized [arterio-venous (a-v) shunting]. In Type B venous profiles, variable but progressive hemoglobin desaturation profiles were interrupted by inflections in the profile that were consistent with fluctuating tissue blood flow and oxygen uptake. End-of-dive saturation of arterial and Type A venous hemoglobin saturation profiles were not significantly different, but did differ from those of Type B venous profiles. These findings provide further support that the dive response of emperor penguins is a spectrum of cardiac and vascular components (including a-v shunting) that are dependent on the nature and demands of a given dive and even of a given segment of a dive.
Exercise-Induced MYC as an Epigenetic Reprogramming Factor That Combats Skeletal Muscle Aging
Authors: Jones Ronald G. , von Walden Ferdinand , Murach Kevin A.
Published: February 2024

Of the “Yamanaka factors” Oct3/4, Sox2, Klf4, and c-Myc (OSKM), the transcription factor c-Myc (Myc) is the most responsive to exercise in skeletal muscle and is enriched within the muscle fiber. We hypothesize that the pulsatile induction of MYC protein after bouts of exercise can serve to epigenetically reprogram skeletal muscle toward a more resilient and functional state.
Cyclic vectors in Dirichlet-type spaces in the unit ball of C^n
Authors: Βαβίτσας Δημήτριος
Published: February 2024

Η εν λογώ διατριβή μελετά κυρίως το πρόβλημα των κυκλικών πολυωνύμων στους χώρους Ντίριχλετ στη μοναδιαία μπάλα στις πολλές μιγαδικές μεταβλητές. Ειδικότερα, χαρακτηρίζουμε πλήρως τα κυκλικά πολυώνυμα στις δύο μιγαδικές μεταβλητές και τα πολυώνυμα μοντέλα σε τυχαία διάσταση. Στοιχεία, θεωρία και εργαλεία από τους τομείς Μιγαδική Ανάλυση, Συναρτησιακή Ανάλυση, Θεωρία Τελεστών, Θεωρία Δυναμικού και Μιγαδική Αναλυτική Γεωμετρία διασταυρώνονται και δίνουν την γόνιμη θεωρία των κυκλικών διανυσμάτων στους χώρους Ντίριχλετ.
Μέτρηση του κινδύνου αγοράς
Authors: Κονταξής Γρηγόριος
Published: February 2024

Μετά την παγκόσμια οικονομική κρίση του 2006-2008, τα χρηματοπιστωτικά ιδρύματα και οι χρηματοοικονομικοί οργανισμοί υιοθέτησαν έναν μεγάλο αριθμό τεχνικών μοντελοποίησης κινδύνου, ώστε να είναι προετοιμασμένα σε περίπτωση μιας νέας μελλοντικής οικονομικής κρίσης. Η παρούσα Διδακτορική Διατριβή εξετάζει τα πιο δημοφιλή μέτρα κινδύνου, όπως το Value at Risk και το Expected Shortfall, με σκοπό τον επανέλεγχο και την αξιολόγηση της αποδοτικότητας τους. Η εργασία δομείται ως ακολούθως: Στο πρώτο κεφάλαιο, γίνεται μια εισαγωγή των εννοιών του κινδύνου. Στο δεύτερο κεφάλαιο, παρουσιάζεται η βιβλιογραφική επισκόπηση των υποδειγμάτων VaR και ES. Στο τρίτο κεφάλαιο, περιγράφονται οι μέθοδοι υπολογισμού των μέτρων κινδύνου. Στο τέταρτο κεφάλαιο, συγκρίνονται οι διαφορετικές μέθοδοι υπολογισμού των VaR και ES σε διαστήματα διακράτησης μιας ημέρας. Στο πέμπτο κεφάλαιο, παρουσιάζεται η σύγκριση μεθόδων υπολογισμού των VaR και ES σε διαστήματα διακράτησης δέκα ημερών. Στο έκτο κεφάλαιο, πραγματοποιείται η αξιολόγηση των μέτρων κινδύνου. Στο έβδομο κεφάλαιο, εξετάζεται η ευαισθησία ενός επιλεγμένου αριθμού μοντέλων όταν μεταβάλλεται το παράθυρο εύρους. Τέλος, τα κεφάλαια οχτώ και εννιά παρουσιάζουν τα συμπεράσματα της διατριβής και τις αδυναμίες της συγκεκριμένης μελέτης.
Clinical and seasonal pattern of dengue in a tertiary care hospital of South West India
Authors: BB Darshan , Holla Ramesh , Unnikrishnan Bhaskaran , Achappa Basavaprabhu , Poovattil Robin , Sharma Ashir , Simmy Shawna , Prateek Suryansh
Published: February 2024

Background Dengue is an emerging global viral disease with an increase 30-fold in incidence in the past fifty years. In the past decade it was restricted to only few a states of South and Northern India but in the recent past it has affected almost all the states in India. The objective of this study was to assess the clinical profile, trends and outcome of dengue cases. Methods This retrospective record based cross-sectional study was conducted in tertiary hospital, Mangaluru in Southern India. The study population included all clinical dengue positive cases over a period of five years. Information from pre-recorded case sheets were used for data collection. The data was analyzed using SPSS Version 20. Results from the analysis have been expressed in percentages, means and graphs. Results The study included 401 dengue cases. Most cases were in the age range of 20-40 years with a male to female ratio of 3:2. Overall seropositivity rate was 23.94% with High IgM prevalence. Monthly distribution showed a maximum incidence in the months of June and July and minimum incidence in January and February. Among the study participants, 91.5% of patients recovered completely and 1.7% of patients had died. 6.8% of patients were discharged against medical advice. Conclusions Dengue continues to be major public health problem in this part of the globe affecting mainly the working age group. Low seropositivity with High IgM prevelance makes dengue an important differential for febrile illness of vague nature and invokes the need for robust public health response to curb the hyper-endemicity.
The impact of energy releasing B-vitamin intake on indices of obesity and cardiac function: a cross-sectional study
Authors: Agraib Lana M. , Al-Shami Islam , Alkhatib Buthaina , Hasan Hanan
Published: February 2024

Background B vitamins play a crucial role in the balance and metabolism of energy. Energy metabolism mainly benefits from the B-complex vitamins. Specifically, decarboxylation, transamination, acylation, oxidation, and reduction of substrates that are ultimately employed in energy intake require thiamin, riboflavin, niacin, and vitamin B6. Vitamin deficiency could lead to chronic disease occurrence. Objectives To assess the impact of energy-releasing B-vitamins intake (B1, B2, B3, and B6) on selected indices of obesity and cardiac function. Methods A cross-sectional study was performed on 491 apparently healthy adults (18-64 years old) between January and May 2019 at Hashemite University, Jordan. Anthropometric measurements were taken, lipid profiles were analyzed, and indices of obesity and cardiac function were calculated. The typical dietary intake of B1, B2, B3, and B6 vitamins was calculated. Results Conicity index (CI) and abdominal volume index (AVI) scores significantly decreased with the increased adjusted vitamin B1 and B6 intake. Also, body roundness index (BRI), weight-adjusted-waist index (WWI), lipid accumulation product (LAP), and atherogenic index of plasma (AIP) scores were decreased with the increase of adjusted B6 intake (p<0.05). The total sample showed a significant inverse weak correlation between energy-adjusted intake of B1 and AVI (r= -0.156, p=0.001) and BRI (r= 0.111, p=0.014). Similar correlations were detected among male participants between energy-adjusted B1 intake and BAI, AVI, and BRI. Female participants had a significant weak inverse correlation between BAI and energy-adjusted B2 (r= -0.180, p=0.029) and B6 intake (r= -0.212, p=0.010). Only B1, the vitamin, significantly explained 2.43 and 1.24% of changes observed in the AVI and BRI scores, respectively (p<0.05). Conclusions Increasing the consumption of B1, B2, and B6 may significantly lower values of indices of obesity and cardiac function regardless of sex differences. Thus reducing the occurrence of obesity and related coronary heart diseases.
Prospective observational study iron deficiency anemia clinical profile in children with sickle cell disease: a study protocol
Authors: Naramreddy Sudheeshreddy , Varma Ashish , Taksande Amar
Published: February 2024

Background Sickle cell disease, a hereditary hemoglobinopathy, presents complex clinical challenges including increased susceptibility to iron deficiency anemia (IDA). However, the clinical profile of IDA in pediatric patients with sickle cell disease still needs to be adequately characterized. This study aims to comprehensively investigate the prevalence, severity, associated risk factors, and potential impact of IDA on morbidity and mortality in this vulnerable population. Methods A prospective observational study will be conducted on 303 children from January 2024 to December 2024 at the Department of Pediatrics, Jawaharlal Nehru Medical College and AVBR Hospital, Sawangi, Wardha. Participants will include pediatric patients diagnosed with sickle cell disease, with informed consent from their parents or legal guardians. Data will be collected through clinical assessments, blood sample analyses for hematological parameters, and systematic recording of relevant clinical information. Statistical analyses, including Fisher’s exact test, Chi-square test, and Student’s t-test, will be used to assess the data, with a significance level set at p < 0.05. Expected outcomes This study aims to provide critical insights into the prevalence and clinical profile of IDA in children with sickle cell disease, shedding light on potential risk factors and correlations with comorbid conditions. Furthermore, it seeks to explore the relationship between IDA and disease-related morbidity and mortality.
The Snowball Sampling Strategy in the Field of Social Sciences. Contexts and Considerations.
Authors: Gierczyk Marcin , Gromkowska-Melosik Agnieszka , Sam Scott Sam , Parker Charlie
Published: February 2024

This article discusses the snowball sampling strategy that has been successfully used for decades in research in the field of social sciences. The focus of this article is only on the application of the strategy in qualitative research, although it can be employed in quantitative research too. Despite its limitations and debatable applicability in some cases, it is methodologically justified and considered very effective in reaching hard-to-reach populations. Referring to the methodological literature, research in which it was adopted and our own experience, we reflect on the contexts and controversies that arise around its implementation.
Competências do profissional de Educação Física na Atenção Primária à Saúde
Authors: Lima Rafael de Oliveira , Andrella João Luiz , Silva Joicy Ferreira , Trapé Átila Alexandre
Published: February 2024

Atenção Primária à Saúde (APS) é a porta de entrada do usuário no Sistema Único de Saúde (SUS). Com uma vasta amplitude de ações que perpassam da prevenção de agravos à promoção da saúde, a APS se desenvolveu para atender o usuário em sua totalidade, ofertando dentre suas atividades as práticas corporais e atividades físicas. Entretanto, a inserção do profissional de Educação Física (EF) nas equipes multiprofissionais na APS ainda é pequena e alguns estudos mostram limitações na formação deste profissional para atuar neste contexto. Sendo assim, este trabalho teve como objetivo investigar os caminhos percorridos desde a for- mação inicial até a percepção sobre o desenvolvimento de competências na atuação dos profissionais de EF que trabalham na APS. Trata-se de um estudo qualitativo, realizado a partir de entrevistas semiestruturadas, de forma remota (Google Meet). A amostra analisada contou com seis profissionais de EF que atuavam na APS em cidades das cinco regiões do país. Foi realizada análise de conteúdo para organizar os resultados das entrevistas, sendo que as unidades de registro foram codificadas em temáticas e na sequência organizadas em categorias: Graduação e Saúde Coletiva, Pós-formação, Atuação Profissional e Competências Profissionais. Como conclusão, os profissionais de EF identificaram lacunas na formação em EF para o trabalho na APS, sendo o contexto pós-formação bastante importante para atender demandas e expectativas para a atuação. Observou-se ainda um grande conhecimento sobre as competências, atrelado ao universo teórico e prático, a partir de um olhar humanizado, para uma conduta profissional eficaz e eficiente.
Adaptive Influence Maximization: Adaptability via Nonadaptability
Authors: Du Hongmin W. , Du Yingfan L. , Zhang Zhao
Published: February 2024

Adaptive influence maximization is an important research problem in computational social networks, which is also a typical problem in the study of adaptive processing of information and adaptive construction of objects. In this paper, we propose a new method that reduces the adaptive influence maximization problem into a nonadaptive one in a different social network, so that an adaptive optimization can be solved by those methods for nonadaptive optimization. In addition, we provide a new approximation algorithm for the submodular maximization problem with a knapsack constraint, which runs in [Formula: see text] time and has performance ratio [Formula: see text], where n is the number of nodes in the network. The ratio is better than the best known previous one with the same running time.

History: Accepted by Erwin Pesch, Area Editor for Heuristic Search & Approximation Algorithms.

Funding: This research is supported in part by the National Natural Science Foundation of China [Grant U20A2068].
Optimal Decision Making Under Strategic Behavior
Authors: Tsirtsis Stratis , Tabibian Behzad , Khajehnejad Moein , Singla Adish , Schölkopf Bernhard , Gomez-Rodriguez Manuel
Published: February 2024

We are witnessing an increasing use of data-driven predictive models to inform decisions in high-stakes situations, from lending and hiring to university admissions. As decisions have implications for individuals and society, there is increasing pressure on decision makers to be transparent about their decision policies. At the same time, individuals may use knowledge, gained by transparency, to invest effort strategically in order to maximize their chances of receiving a beneficial decision. Our goal is to find decision policies that are optimal in terms of utility in such a strategic setting. First, we characterize how strategic investment of effort by individuals leads to a change in the feature distribution. Using this characterization, we show that, in general, optimal decision policies are hard to find in polynomial time, and there are cases in which deterministic policies are suboptimal. Then, we demonstrate that, if the cost individuals pay to change their features satisfies a natural monotonicity assumption, we can narrow down the search for the optimal policy to a particular family of decision policies with a set of desirable properties, which allow for a highly effective polynomial time-heuristic search algorithm using dynamic programming. Finally, under no assumptions on the cost, we develop an iterative search algorithm that is guaranteed to converge to locally optimal decision policies. Experiments on synthetic and real credit card data illustrate our theoretical findings and show that the decision policies found by our algorithms achieve higher utility than those that do not account for strategic behavior.

This paper was accepted by Vivek Farias, data science.

Funding: This work was supported by Machine Learning Cluster of Excellence [EXC #2064/1, Project #390727645], H2020 European Research Council [Grant 945719], and Bundesministerium für Bildung und Forschung [Grant 01IS18039B].

Supplemental Material: The online appendix and data files are available at https://doi.org/10.1287/mnsc.2021.02567
Disaster Lending: “Fair” Prices but “Unfair” Access
Authors: Begley Taylor A. , Gurun Umit G. , Purnanandam Amiyatosh , Weagley Daniel
Published: February 2024

We find the Small Business Administration’s disaster-relief home loan program denies significantly more loans in areas with larger shares of minorities, subprime borrowers, and higher income inequality. We find that risk-insensitive loan pricing, a feature present in many regulated and government-run lending programs, is an important driver of these disparities in access to credit. The differences in denial rates are disproportionately high compared with private-market lending and government-insured risk-sensitive loan pricing programs. Thus, despite ensuring “fair” prices, the use of risk-insensitive pricing may lead to “unfair” access to credit.

This paper was accepted by Victoria Ivashina, finance.

Supplemental Material: The online appendix and data files are available at https://doi.org/10.1287/mnsc.2021.03199 .
When Yield Is Not the Only Supply Uncertainty: Newsvendor Model of a Trade Agent
Authors: Çakıcı Özden Engin , Karaesmen Itir
Published: February 2024

Problem definition: We study the procurement decisions of a trade agent: The agent chooses a bid (unit price to pay) to procure the goods available from seller(s). If the agent wins the bid, the supply is used to meet the buyer’s demand. Methodology/results: The trade agent’s single-period, single-product problem is a new type of newsvendor problem. We analyze the agent’s optimal bid for a seller with yield uncertainty. We show that the bid outcome distribution needs to satisfy an easy-to-check condition but no conditions on the yield distribution are needed for a unique optimal bid to exist. We also show that the expected sales-to-supply ratio that measures scarcity affects the optimal bid. We investigate the monotonicity of the optimal bid with respect to economic parameters, demand, and distributions of bid outcome and yield. The agent’s problem with multiple sellers is also a novel newsvendor network problem. For the two-seller case, we show when diversification is optimal for the agent. We show that working with both sellers may not always be optimal despite the opportunity for risk pooling and bidding only at the unreliable seller may be optimal even when the other seller is reliable. Managerial implications: We make the following recommendations for the agent: (i) bid at a seller only when the expected sales-to-supply ratio for a seller is higher than the critical ratio, considering the agent’s cost of underage and overage, (ii) increase the bid if the bid outcome distribution increases in the reversed hazard rate order, and (iii) increase or decrease the bid depending on the demand-to-supply ratio when a seller’s expected yield increases. Inclusion of additional sellers lowers the optimal bids across the seller network, but it may not be optimal to bid at all sellers. For the two-seller problem, whether to diversify is a decision easily made by computing the expected benefit of bidding at each seller.

Supplemental Material: The online appendix is available at https://doi.org/10.1287/msom.2023.0190 .
Post-injection quadriceps contracture treated with horizontal distal Z quadricepsplasty: A Case Report
Authors:   Department of Orthopaedics, AIIMS Kalyani, Nadia, West Bengal, India., Biswas Mridul , Sahoo Samrat S ,   Department of Orthopaedics, AIIMS Kalyani, Nadia, West Bengal, India.
Published: February 2024

Introduction: Post-injection quadriceps contracture (PIQC) is a rare disease entity nowadays as the route of injection has been changed from intramuscular to intravenous. Many types of quadricepsplasty were described with different complications. Case Report: A 5-year 6-month-old boy was presented with right quadriceps contracture which was managed with distal horizontal Z quadricepsplasty and immobilization with a slab in an early post-operative day. After 4 weeks of static quadriceps exercise, then range of motion exercises was started. Conclusion: PIQC is a rare entity and can be treated successfully with horizontal z plasty. Knee range of movement can be achieved without any significant extension lag and skin complications. Keywords: Quadricepsplasty, quadriceps contracture, horizontal z plasty, post-injection, children.
Cotton knitted fabric waste as reinforcement in cement screed
Authors:   University of Split, Faculty of Civil Engineering, Architecture and Geodesy, Matice hrvatske 15, 21000 Split, Croatia, Juradin Sandra , Bartulović Bruno , Žižić Dujmo ,   University of Split, Faculty of Civil Engineering, Architecture and Geodesy, Matice hrvatske 15, 21000 Split, Croatia, Mrakovčić Silvija ,   University of Rijeka, Faculty of Civil Engineering,, Radmile Matejčić 3, 51000 Rijeka, Croatia
Published: February 2024

Cement screed consists of cement, sharp sand and water, laid as a thin layer over the concrete subfloor. Although the screed is strong, it can be additionally reinforced with fibres, most often polypropylene fibres. In this study, cotton knitted fabric waste (CKFW) was obtained from a local factory producing underwear to reinforce the cement screed. A total of eight mixtures were made: reference mixture, screed reinforced with polypropylene fibres and six mixtures reinforced with CKFW. CKFW was added in 1,25 %, 2,50 % and 5,00 % of the total volume. Before adding to the mixtures, the first CKFW group was saturated with tap water, whereas, the second CKFW group was saturated with dispersion that improves adhesion. The density and air content of the fresh mixtures were tested, and the compressive strength and flexural strength were determined when the specimens were 28 days old. The specific fracture energy is determined based on the curve from the plot of load vs. displacement. The CKFW increases the ductility of cement screeds, although it has no significant effect on the compressive and flexural strength of the specimens. The CKFW that was saturated with tap water achieved better results.
Pre-problem families: predictive analytics and the future as the present
Authors: Edwards Rosalind , Gillies Val , Gorin Sarah , Vannier-Ducasse Hélène
Published: February 2024

Predictive analytics is seen as a way of identifying the risk of future problems in families. Integral to such automated predictive analysis is a shift in time frames that redraws the relationship between families and the state, to potentially intervene on an anticipatory basis of ‘what hasn’t happened but might’. In the process, human subjects are reformulated as disembodied objects of data-driven futures. The article explains this process and fills a significant gap in knowledge about parents’ views of this development. We draw on group and individual discussions with parents across Great Britain to consider their understanding of predictive analytics and how comfortable they are with it. Parents’ concerns focused on inaccuracies in the data used for prediction, the unfair risk of false positives and false negatives, the deterministic implications of the past predicting the future, and the disturbing potential of being positioned in what was a pre-problem space. We conclude with policy implications.
Bent and Broken
Authors: Grass Sean
Published: February 2024

Abstract: This essay reflects on Charles Dickens’s Great Expectations and what it has meant, and continues to mean, to me as a reader and scholar of Dickens. Beginning from the observation that students seem invariably to detest Pip, the essay explains how reading the novel hermeneutically, as a lesson for my own life, has helped me to ruminate the complex feelings of shame that I have long felt regarding my own working-class childhood, and my own Estella. What I suggest finally is that, while neither of Great Expectations ’s endings is particularly happy, the novel ends with a muted but hopeful message about finding contentment, peace, and even joy despite being bent and broken
Of Coffee Cups and Beer Glasses: Material Drinking Culture and Colonial Beverages in Rural Northwest Germany, 1600–1800
Authors: Bovenkerk Henning
Published: February 2024

abstract: This article explores the spread of material drinking culture of colonial and domestic beverages in rural regions in early modern northwest Germany. The rapid diffusion of colonial beverages in early modern Europe is well established in literature on consumption and material culture. But historians have yet to adequately answer questions concerning the way these beverages influenced material culture in intermediate regions, which were neither centers of (global) trade networks nor at their periphery. This article argues that while rural, intermediate areas lagged behind the development of centers, they also produced new forms of material drinking culture distinct from cities.
On Sunlit Fields: The Swabian Children, Legal Personhood, and the Tyrolean Statthalterei's Edict of 1867
Authors: Speed J. Andie
Published: February 2024

abstract: In the 1860s, legislators and bureaucrats in the Alps crafted laws to govern the migrations of the so-called Swabian Children, requiring them to meet specific obligations for the right to travel abroad. At the time of passage, these laws had a facilitative purpose. They were intended to funnel children abroad so they could avoid the degrading effects of begging and factory work. Decades later and inspired by growing moral outrage, regional school authorities repurposed these legal norms to inhibit the numbers of children heading abroad. This article analyzes the shifting sensibilities about territorial sovereignty and childhood to show how these norms were transformed via a dialogue between text and application, laws and their enforcement.
Subwavelength Bessel beam arrays with high uniformity based on a metasurface
Authors: Wu Chenyang , Huang Xuanlun , Yipeng Ji , Wang Jiaxing , Chang-Hasnain Connie J.
Published: February 2024

Bessel beam arrays are highly attractive due to non-diffraction properties, parallel processing, and large capacity capabilities. However, conventional approaches of generating Bessel beams, such as spatial light modulators, axicons, and diffraction optical elements, suffer from various limitations of system complexity and bulkiness, low uniformity, and limited numerical aperture (NA). The limited NA imposes constraints on achieving minimal full width at half maximum (FWHM) of the Bessel beam, ultimately compromising the resolution of the beam. In this study, we demonstrate a method for generating Bessel beam arrays with regular and random patterns via an ultra-compact metasurface. This approach integrates the phase profile of an optimized beam splitter with a meta-axicon. The Bessel beam arrays exhibit subwavelength dimensions of FWHM (590 nm, ∼0.9λ) and relatively high uniformity of 90% for NA=0.2 and 69% for NA=0.4. Furthermore, the method achieves effective suppression of background noise and zeroth-order intensity compared to methods based on Dammann grating (DG) based metasurfaces. The proposed method highlights potential applications of Bessel beam arrays in various fields, such as laser machining, optical communication, and biomedical imaging.
Optical signatures of thermal damage on ex-vivo brain, lung and heart tissues using time-domain diffuse optical spectroscopy
Authors: Bossi Alessandro , Bianchi Leonardo , Saccomandi Paola , Pifferi Antonio
Published: February 2024

Thermal therapies treat tumors by means of heat, greatly reducing pain, post-operation complications, and cost as compared to traditional methods. Yet, effective tools to avoid under- or over-treatment are mostly needed, to guide surgeons in laparoscopic interventions. In this work, we investigated the temperature-dependent optical signatures of ex-vivo calf brain, lung, and heart tissues based on the reduced scattering and absorption coefficients in the near-infrared spectral range (657 to 1107 nm). These spectra were measured by time domain diffuse optics, applying a step-like spatially homogeneous thermal treatment at 43 °C, 60 °C, and 80 °C. We found three main increases in scattering spectra, possibly due to the denaturation of collagen, myosin, and the proteins' secondary structure. After 75 °C, we found the rise of two new peaks at 770 and 830 nm in the absorption spectra due to the formation of a new chromophore, possibly related to hemoglobin or myoglobin. This research marks a significant step forward in controlling thermal therapies with diffuse optical techniques by identifying several key markers of thermal damage. This could enhance the ability to monitor and adjust treatment in real-time, promising improved outcomes in tumor therapy.
Design method for eliminating spectral line tilt in a multiple sub-pupil ultra-spectral imager (MSPUI)
Authors: Zhang Xv , Fang Xin , Li Tao , Wang Xiao Xv , Gu Guo Chao , Li Han Shuang , Lin Guan Yu , Li Bo
Published: February 2024

A multiple sub-pupil ultra-spectral imaging system designed with a single spectrometer and detector can simultaneously detect multiple-channel spectra with ultra-high spectral resolution. However, due to using a prism in the system's front end, the nonlinear dispersion introduces spectral line tilt in the imaging spectra. This phenomenon can lead to bias in the final spectral data. To eliminate this issue, we propose a new design by introducing a second prism to correct this spectral tilt in the system. The angle of spectral line tilt generated by the nonlinear dispersion of the first prism is derived. It provides the theoretical basis for characterizing the second complementary prism. Finally, a UV multiple sub-pupil ultra-spectral imaging system is designed. The system employs two pupil separation prisms and one flat panel array to segment the pupil in three channels, each operating within spectral ranges of 180∼210 nm, 275∼305 nm, and 370∼400 nm, respectively. The spectral resolutions in all three channels are better than 0.1 nm. The corrected spectral line tilt is less than 1/3 of a pixel in the two channels with pupil separation prisms. At a Nyquist frequency of 30 lp/mm, the modulation transfer functions of all three channels are greater than 0.7, ensuring imaging quality. The design results indicate that the method proposed in this paper, utilizing complementary prisms, can effectively correct the spectral line tilt caused by the nonlinear dispersion of the pupil separation prisms. This design approach can be a reference for developing multiple sub-pupil ultra-spectral imaging systems.
Hybrid integrated thin-film lithium niobate–silicon nitride electro-optical phased array incorporating silicon nitride grating antenna for two-dimensional beam steering
Authors: Lee Woo-Bin , Kwon Yun-Jae , Kim Do-Hyung , Sunwoo Yoon-Ho , Lee Sang-Shin
Published: February 2024

This study proposes a solid-state two-dimensional beam-steering device based on an electro-optical phased array (EOPA) in thin-film lithium niobate (TFLN) and silicon nitride (SiN) hybrid platforms, thereby eliminating the requirement for the direct etching of TFLN. Electro-optic (EO) phase modulator array comprises cascaded multimode interference couplers with an SiN strip-loaded TFLN configuration, which is designed and fabricated via i-line photolithography. Each EO modulator element with an interaction region length of 1.56 cm consumed a minimum power of 3.2 pJ/π under a half-wave voltage of 3.64 V and had an estimated modulation speed of 1.2 GHz. Subsequently, an SiN dispersive antenna with a waveguide grating was tethered to the modulator array to form an EOPA, facilitating the out-of-plane radiation of highly defined near-infrared beams. A prepared EOPA utilized EO phase control and wavelength tuning near 1550 nm to achieve a field-of-view of 22° × 5° in the horizontal and vertical directions. The proposed hybrid integrated platform can potentially facilitate low-power and high-speed beam steering.
Polarization-insensitive high-numerical-aperture metalens for wide-field super-resolution imaging
Authors: Chen Lieyu , Liu Wenwei , Li Zhancheng , Zhang Yuebian , Cheng Hua , Tian Jianguo , Chen Shuqi
Published: February 2024

The development of super-oscillatory lens (SOL) offers opportunities to realize far-field label-free super-resolution microscopy. Most microscopes based on a high numerical aperture (NA) SOL operate in the point-by-point scanning mode, resulting in a slow imaging speed. Here, we propose a high-NA metalens operating in the single-shot wide-field mode to achieve real-time super-resolution imaging. An optimization model based on the exhaustion algorithm and angular spectrum (AS) theory is developed for metalens design. We numerically demonstrate that the optimized metalens with an NA of 0.8 realizes the imaging resolution (imaging pixel size) about 0.85 times the Rayleigh criterion. The metalens can achieve super-resolution imaging of an object with over 200 pixels, which is one order of magnitude higher than the unoptimized metalens. Our method provides an avenue toward single-shot far-field label-free super-resolution imaging for applications such as real-time imaging of living cells and temporally moving particles.
Toward high-energy few-cycle optical vortices with minimized topological charge dispersion
Authors: Furch Federico J. , Arisholm Gunnar
Published: February 2024

A simple approach to generate high-energy few-cycle optical vortices with minimized topological charge dispersion is introduced. By means of numerical simulations, it is shown that, by leveraging the intrinsic properties of optical parametric chirped pulse amplification (OPCPA), clean transfer of topological charge from a high-energy narrowband pump pulse to a broadband idler is feasible under certain particular conditions, enabling the generation of high-energy few-cycle vortex pulses with extremely low topological charge dispersion.
Decolorization, spectral broadening, and luminescence enhancement in Tb:Y2O3 transparent ceramics through vacuum thermal reduction
Authors: Zhang Cong , Qi Jianqi , Liang Lexing , Yan Yonggang , Lu Tiecheng
Published: February 2024

Tb3+ is extensively employed in magneto-optical devices and luminescent materials owing to its distinctive physical properties. However, under certain conditions, trivalent Tb3+ readily undergoes oxidation to tetravalent Tb4+, significantly reducing the performance of devices containing Tb3+. In this Letter, we report a technique called dual-annealing (DA) post-treatment, which effectively solves Tb oxidation issues by utilizing the reducibility of the vacuum environment. High-quality Tb:Y2O3 transparent ceramics were prepared with in-line transmittance of ∼80% at 800 nm. Subsequently, the prepared ceramics were subjected to DA treatment. The optical, photoluminescence, radioluminescence, and x-ray imaging properties of DA samples were comprehensively compared with those of conventionally single-annealed (SA) samples. The coloration of Tb:Y2O3 transparent ceramics due to Tb4+ absorption was eliminated by DA. Notably, the DA sample showed a 3.28-fold increase in photoluminescence intensity and a 2.73-fold increase in radioluminescence intensity compared with the traditional SA sample. DA post-treatment enables Tb: Y2O3 transparent ceramics to achieve x-ray imaging capabilities. This Letter presents a simple, efficient, and universally applicable post-treatment technique expected to replace conventional hydrogen annealing in numerous scenarios.
Microwave re-excitation of femtosecond laser tagging for highly flexible velocimetry
Authors: Reinbacher Fynn , Bidwai Sarang , Michael James
Published: February 2024

Molecular tagging velocimetry is typically species specific and limited by excited state/species lifetimes. We utilize laser-generated ionization, long-lived anions, and a time-delayed microwave pulse to monitor the tagged region up to several milliseconds. This non-resonant excitation and microwave interaction is demonstrated in a range of gas mixtures. Signal levels show up to 1000-fold improvement, and the flexibility in interrogation time allows for velocity measurements over a large dynamic range (1-100 m/s) with single-shot precision of <5%. This approach has the potential for wide application over a range of relevant gas compositions, temperatures, and pressures.
A individually randomized controlled trial comparing Healer-led vs. clinician- led training to improve personal protective equipment use among traditional healers in South Africa
Authors: Audet Carolyn M. , Seabi Tshegofatso , Oyekunle Taofik , Hove Jennifer , Wagner Ryan G.
Published: February 2024

Like allopathic healthcare workers, healers are also exposed to patients’ blood and body fluids. A widespread practice is the traditional “injection,” in which the healer performs subcutaneous incisions to rub herbs directly into the bloodied skin, resulting in 1,500 blood exposures over their lifetime. We tested the impact of healer-led PPE training, staffed by trained traditional healers who reported using PPE during each risky clinical encounter vs. healthcare worker (HCW)-led PPE training sessions. We randomized 136 healers into one of the two study arms (67 in the healer-led group, 69 in the HCW-led group) and assessed the impact of trainer on PPE skills and use over a six-month period. All healers received one in-person day of didactic and practical training followed by three sessions at the healers’ home. Participants were largely female (80%), averaged 51 years old, and practiced as a healer for an average of 17 years. Almost 44% either disclosed themselves as HIV+ or received a positive HIV test result at study initiation. Healers in the HCW arm showed equivalent PPE scores as those trained by traditional healers at baseline and at seven months. Healers in both arms self-reported high levels of glove use during”injections,” with no statistical difference of use by study arm. When we assessed actual gloves and razor blades disposed of each month, a similar trend emerged. No one seroconverted during the study period. The need for PPE support among traditional healers cannot be ignored. Traditional healers can be trained to effectively disseminate PPE knowledge and skills to other traditional healers. With an estimated 200,000 traditional healers in South Africa, it is imperative that all of them have access to PPE training and supplies to prevent HIV, HCV, or HBV infections.

Trial registration: ClinicalTrials.gov, NCT04440813. Registered 17 June 2020, https://clinicaltrials.gov/ct2/show/NCT04440813.
The bloodstream form of Trypanosoma brucei displays non-canonical gluconeogenesis
Authors: Kovářová Julie , Moos Martin , Barrett Michael P. , Horn David , Zíková Alena
Published: February 2024

Trypanosoma brucei is a causative agent of the Human and Animal African Trypanosomiases. The mammalian stage parasites infect various tissues and organs including the bloodstream, central nervous system, skin, adipose tissue and lungs. They rely on ATP produced in glycolysis, consuming large amounts of glucose, which is readily available in the mammalian host. In addition to glucose, glycerol can also be used as a source of carbon and ATP and as a substrate for gluconeogenesis. However, the physiological relevance of glycerol-fed gluconeogenesis for the mammalian-infective life cycle forms remains elusive. To demonstrate its (in)dispensability, first we must identify the enzyme(s) of the pathway. Loss of the canonical gluconeogenic enzyme, fructose-1,6-bisphosphatase, does not abolish the process hence at least one other enzyme must participate in gluconeogenesis in trypanosomes. Using a combination of CRISPR/Cas9 gene editing and RNA interference, we generated mutants for four enzymes potentially capable of contributing to gluconeogenesis: fructose-1,6-bisphoshatase, sedoheptulose-1,7-bisphosphatase, phosphofructokinase and transaldolase, alone or in various combinations. Metabolomic analyses revealed that flux through gluconeogenesis was maintained irrespective of which of these genes were lost. Our data render unlikely a previously hypothesised role of a reverse phosphofructokinase reaction in gluconeogenesis and preclude the participation of a novel biochemical pathway involving transaldolase in the process. The sustained metabolic flux in gluconeogenesis in our mutants, including a triple-null strain, indicates the presence of a unique enzyme participating in gluconeogenesis. Additionally, the data provide new insights into gluconeogenesis and the pentose phosphate pathway, and improve the current understanding of carbon metabolism of the mammalian-infective stages of T. brucei.
Study on mechanical properties of interbedded rock masses with microcrack based on thermal-mechanical coupling
Authors: Qiu Liewang , Xie Liangfu , Qin Yongjun , Wang Jianhu , Liu Shan , Qian Jiangu
Published: February 2024

The mechanical properties of deep rock masses are significantly influenced by temperature and other factors. The effect of temperature on the strength of deep rock masses will pose a serious challenge to deep resource exploitation and engineering construction. In this paper, the thermal-mechanical coupling calculation model is established by particle flow code (PFC2D) to study the uniaxial compression response of rock masses with microcracks after temperature load. The strength of failure, microcracks, and strain was analyzed. The results show that: (i) When the soft rock thickness ratio Hs/H < 0.5, the displacement caused by the applied temperature is concentrated at the structural plane, and the contact force is concentrated at the end of the initial microcrack. When Hs/H ≥ 0.5, the displacement caused by the applied temperature is concentrated on both sides of the initial microcrack, and the contact force is concentrated in the hard rock area. (ii) The number of microcracks decreases with the increase of soft rock thickness under different working conditions. When the soft rock thickness ratio Hs/H < 0.5, the relationship curve between the number of microcracks and the vertical strain shows two stages of change. When Hs/H ≥ 0.5, the relationship curve between the number of cracks and the vertical strain changes shows three stages of change. (iii) When the soft rock thickness ratio Hs/H < 0.5, the failure strength decreases with the increase of soft rock thickness ratio at T = 100°C and 200°C. When T = 300°C and 400°C, the failure strength decreased first and then increased. When Hs/H ≥ 0.5, the failure strength increases with the increase of soft rock thickness at T = 200°C, 300°C, and 400°C. At T = 100°C, the failure strength decreases with the increase of soft rock thickness.
Impact of alternative Non-Pharmaceutical Interventions strategies for controlling COVID-19 outbreak in Bangladesh: A modeling study
Authors: Shimul Shafiun Nahin , Hussain Mofakhar , Faisel Abul Jamil , Hamid Syed Abdul , Sultana Nasrin , Kuddus Md Abdul
Published: February 2024

The COVID-19 pandemic has been a major health concern in Bangladesh until very recently. Although the Bangladesh government has employed various infection control strategies, more targeted Non-Pharmaceutical interventions (NPIs), including school closure, mask-wearing, hand washing, and social distancing have gained special attention. Despite significant long-term adverse effects of school closures, authorities have opted to keep schools closed to curb the spread of COVID-19 infection. However, there is limited knowledge about the impact of reopening schools alongside other NPI measures on the course of the epidemic. In this study, we implemented a mathematical modeling framework developed by the CoMo Consortium to explore the impact of NPIs on the dynamics of the COVID-19 outbreak and deaths for Bangladesh. For robustness, the results of prediction models are then validated through model calibration with incidence and mortality data and using external sources. Hypothetical projections are made under alternative NPIs where we compare the impact of current NPIs with school closures versus enhanced NPIs with school openings. Results suggest that enhanced NPIs with schools opened may have lower COVID-19 related prevalence and deaths. This finding indicates that enhanced NPIs and school openings may mitigate the long-term negative impacts of COVID-19 in low- and middle-income countries. Potential shortcomings and ways to improve the research are also discussed.
The lived experience of people affected by cancer: A global cross-sectional survey protocol
Authors: Cayrol Julie , Wakefield Claire E. , Ilbawi André , Donoghoe Mark , Hoffman Ruth , Echodu Moses , Schilstra Clarissa , Ortiz Roberta , Wiener Lori
Published: February 2024

A diagnosis of cancer impacts the person’s physical and mental health and the psychosocial and financial health of their caregivers. While data on the experience of living with cancer is available, there is a dearth of data from persons in low- and middle-income countries (LMICs). The perspectives of other impacted individuals also remain understudied (e.g., bereaved family members), as well as the impact on survivors and their families over time. The objective of this study is to describe the psychosocial and financial impact of cancer on people diagnosed with cancer as a child, adolescent or adult, their families/caregivers, and the family members of those who have died from cancer, in high-income countries (HICs) and LMICs. This study is an observational, descriptive, quantitative study. Data will be collected anonymously via a digital online cross-sectional survey distributed globally by the World Health Organization (WHO) via the LimeSurvey software. Participants will include (a) adults aged 18+ who have been diagnosed with cancer at any age, who are currently undergoing cancer treatment or who have completed cancer treatment; (b) adult family members of individuals of any age with a cancer diagnosis, who are currently undergoing cancer treatment or who have completed cancer treatment; and (c) bereaved family members. Participants will be anonymously recruited via convenience and snowball sampling through networks of organisations related to cancer. Survey results will be analysed quantitatively per respondent group, per time from diagnosis, per disease and country. Results will be disseminated in peer-reviewed journals and at scientific conferences; a summary of results will be available on the WHO website. This study will suggest public health interventions and policy responses to support people affected by cancer and may also lead to subsequent research focusing on the needs of people affected by cancer.