bluuebunny/crossref_metadata_2025 huggingface dataset:
The mitochondrial physiology of torpor in ruby-throated hummingbirds, Archilochus colubris
Authors: Hutchinson Amalie J. , Staples James F. , Gugleilmo Christopher G.
Published: September 2024

Hummingbirds save energy by facultatively entering torpor, but the physiological mechanisms underlying this metabolic suppression are largely unknown. We compared whole-animal and pectoralis mitochondrial metabolism between torpid and normothermic ruby-throated hummingbirds (Archilochus colubris). When fasting, hummingbirds were exposed to 10°C ambient temperature at night and they entered torpor; average body temperature decreased by nearly 25°C (from ∼37 to ∼13°C) and whole-animal metabolic rate (V̇O2) decreased by 95% compared with normothermia, a much greater metabolic suppression compared with that of mammalian daily heterotherms. We then measured pectoralis mitochondrial oxidative phosphorylation (OXPHOS) fueled by either carbohydrate or fatty acid substrates at both 39°C and 10°C in torpid and normothermic hummingbirds. Aside from a 20% decrease in electron transport system complex I-supported respiration with pyruvate, the capacity for OXPHOS at a common in vivo temperature did not differ in isolated mitochondria between torpor and normothermia. Similarly, the activities of pectoralis pyruvate dehydrogenase and 3-hydroxyacyl-CoA dehydrogenase did not differ between the states. Unlike heterothermic mammals, hummingbirds do not suppress muscle mitochondrial metabolism in torpor by active, temperature-independent mechanisms. Other mechanisms that may underly this impressive whole-animal metabolic suppression include decreasing ATP demand or relying on rapid passive cooling facilitated by the very small body size of A. colubris.
Landmark knowledge overrides optic flow in honeybee waggle dance distance estimation
Authors: Menzel Randolf , Galizia C. Giovanni
Published: September 2024

Honeybees encode in their waggle dances the vector (distance and direction) of an outbound flight to a food source or a new nest site. Optic flow has been identified as the major source of information in the distance estimation. Additional components of distance estimation were also identified, e.g. the sequence of experienced landmarks. Here, we address the question of whether bees also use the landscape memory developed during exploratory orientation flights to estimate distance. We took advantage of the fact that flights in a narrow tunnel lead to further distance measures as a result of higher optic flow. We found that this effect was lost when bees had explored the area in which the tunnel was located and when they had somewhat restricted visual access to the surrounding environment through the mesh on top of the tunnel. These data are interpreted in the context of other findings about the structure of navigational memory in bees that develops during exploratory orientation flights. In particular, the data suggest that bees embed distance measures into a representation of navigational space that stores previously experienced landscape features.
Rating of Perceived Exertion in a Typical Isometric Handgrip Training Protocol in Normotensive and Hypertensive Individuals
Authors: Melo Paulo Henrique , Silva Jefferson Maxwell de Farias , Silva Gustavo Oliveira , Rodrigues Sergio Luiz Cahu , Kanegusuku Hélcio , Correia Marilia Almeida , Andrade-Lima Aluísio , Ritti-Dias Raphael Mendes , Farah Breno Quintella
Published: September 2024

Introduction

The typical isometric handgrip exercise (IHG) protocol, consisting of four sets of 2 min each at 30% of maximal voluntary contraction, has demonstrated effectiveness in reducing blood pressure for both normotensive and hypertensive individuals. Despite its relatively low intensity, patients frequently report difficulties in executing this protocol. Surprisingly, no prior study has detailed the protocol’s level of exertion. Thus, the aim of this study was to describe the rating of perceived exertion (RPE) during a typical IHG protocol in both normotensive and hypertensive individuals.

Methods

In this secondary data analysis, 16 normotensive men (21 ± 2 yr old) and 14 hypertensive individuals (60 ± 7 yr old; 28% men) underwent an IHG session with the typical protocol of 4 × 2-min sets bilaterally (alternating hands) at 30% of their maximal voluntary contraction with a 1-min rest interval. The RPE of the active muscles was evaluated using the OMNI Perceived Exertion Scale for Resistance Exercise every 30 s during the sets.

Results

In normotensive individuals, there was a progressive increase in RPE over time (30–120 s) in all sets (P < 0.001), with the second set resulting in higher RPE than the first set in both hands (P < 0.05). Among hypertensive individuals, there was an increase in RPE only up to 90 s (P < 0.001) in all sets, with no further difference between 90 and 120 s (P > 0.05). In the right hand, but not in the left hand, the RPE of the first set was different from the second set (P < 0.001).

Conclusion

RPE increased within and among sets in both normotensive and hypertensive individuals during IHG.
Model-assisted optimization of linear algebra routines on multi-GPU computing systems
Authors: Αναστασιάδης Πέτρος
Published: September 2024

Οι πράξεις γραμμικής άλγεβρας εμφανίζονται συχνά σε εφαρμογές υψηλής απόδοσης (HPC), καθιστώντας την απόδοσή τους κρίσιμη για την επίτευξη βέλτιστης κλιμάκωσης. Καθώς πολλές σύγχρονες συστάδες HPC περιλαμβάνουν κόμβους με πολλαπλούς επεξεργαστές γραφικών (GPUs), οι πράξεις BLAS συχνά εκφορτώνονται σε GPUs, καθιστώντας απαραίτητη τη χρήση βελτιστοποιημένων βιβλιοθηκών για τη διασφάλιση της απόδοσης. Ωστόσο, η βελτιστοποίηση των BLAS σε πολλαπλές GPUs εισάγει πολλές προκλήσεις παρόμοιες με εκείνες του κατανεμημένου υπολογισμού, όπως την αποσύνθεση δεδομένων, την δρομολόγηση υποπροβλημάτων και την επικοινωνία μεταξύ GPU με διακριτές μνήμες. Αυτή η πολυπλοκότητα καθιστά την βελτιστοποίηση των BLAS πολύ περίπλοκη, οδηγώντας σε πτώση απόδοσης ή μεμονωμένες λύσεις που λειτουργούν μονο σε μερικά σύστήματα. Για να αντιμετωπίσουμε αυτά τα ζητήματα, προτείνουμε μια προσέγγιση αυτόματης βελτιστοποίησης με τη βοήθεια μοντελοποίησης: εισάγουμε διάφορα μοντέλα απόδοσης για τις BLAS και τα ενσωματώνουμε στο PARALiA, μια ολοκληρωμένη βιβλιοθήκη BLAS. Το PARALiA χρησιμοποιεί μοντέλα επίδοσης για την δυναμική αυτόματη βελτιστοποίηση της εκτέλεσης των BLAS, προσαρμόζοντας κρίσιμες παραμέτρους απόδοσης για κάθε συγκεκριμένο πρόβλημα και σύστημα κατά την εκτέλεση. Αυτή η αυτόματη βελτιστοποίηση συνδυάζεται με έναν δρομολογητή εργασιών, οδηγώντας σε αποδοτική κατανομή δεδομένων και απόδοση πόρων. Το PARALiA παρέχει κορυφαία απόδοση και ενεργειακή αποδοτικότητα και ενσωματώνει την ικανότητα προσαρμογής σε ετερογενή συστήματα και σενάρια μέσω αποφάσεων βασισμένων σε μοντέλα. Τέλος, εστιάζουμε στον πυρήνα GEMM, επεκτείνοντας το PARALiA με έναν προσαρμοσμένο στατικό δρομολογητή που ενσωματώνει νέες βελτιστοποιήσεις στον αλγόριθμο και την επικοινωνία της GEMM βασισμένες σε μοντέλα (PARALiA-GEMMex), ο οποίος παρέχει σημαντικά υψηλότερη απόδοση από τις προηγούμενες βιβλιοθήκες.
A Bioconductor workflow for processing, evaluating, and interpreting expression proteomics data
Authors: Hutchings Charlotte , Dawson Charlotte S. , Krueger Thomas , Lilley Kathryn S. , Breckels Lisa M.
Published: September 2024

Background Expression proteomics involves the global evaluation of protein abundances within a system. In turn, differential expression analysis can be used to investigate changes in protein abundance upon perturbation to such a system. Methods Here, we provide a workflow for the processing, analysis and interpretation of quantitative mass spectrometry-based expression proteomics data. This workflow utilises open-source R software packages from the Bioconductor project and guides users end-to-end and step-by-step through every stage of the analyses. As a use-case we generated expression proteomics data from HEK293 cells with and without a treatment. Of note, the experiment included cellular proteins labelled using tandem mass tag (TMT) technology and secreted proteins quantified using label-free quantitation (LFQ). Results The workflow explains the software infrastructure before focusing on data import, pre-processing and quality control. This is done individually for TMT and LFQ datasets. The application of statistical differential expression analysis is demonstrated, followed by interpretation via gene ontology enrichment analysis. Conclusions A comprehensive workflow for the processing, analysis and interpretation of expression proteomics is presented. The workflow is a valuable resource for the proteomics community and specifically beginners who are at least familiar with R who wish to understand and make data-driven decisions with regards to their analyses.
The effect of chiropractic spinal manipulation on the H-reflex and muscle strength in children with cerebral palsy: A feasibility study
Authors: Duehr Jenna , Niazi Imran Khan , Nedergaard Rasmus Bach , Taylor Denise , Haavik Heidi
Published: September 2024

Background Children with cerebral palsy (CP) have deficits in various aspects of motor control, including motor neuron excitability, which can affect muscle strength, gait, and ability to perform activities of daily living. Previous research on chiropractic spinal manipulation in healthy adults, athletes, and a brain-injured population has indicated improvements in motor neuron excitability, muscle strength, and various aspects of motor control. Thus, chiropractic spinal manipulation may improve motor control in children with CP. Methods Children with spastic diplegic CP, aged 8-13 years, were recruited for a randomized, controlled feasibility study. Feasibility was assessed in terms of recruitment strategy and rate, data collection procedures, equipment, intervention, and compliance. Results Three children completed the data collection comprising pre- and post-measurements of the H reflex, V-wave, and muscle strength. The recruitment strategy and rate were not feasible. The data collection procedures were appropriate and complied with, except for the V-wave measurements. The H-reflex threshold decreased and s50 and slope increased in the participants who received chiropractic spinal manipulation; the opposite was seen in the control group. The changes in MVC force were inconsistent between subjects. Conclusion This study answered some important feasibility questions regarding conducting a large-scale randomized controlled study with the same design. Some aspects proved feasible, such as H-reflex recordings, and some aspects, such as recruitment methods and V-wave recordings, need to be altered for future research in this area.
An Emancipatory Paradigm for Participatory Research on Wartime Childhood. War Childhood Museum in Sarajevo Case Study
Authors: PILARSKA JUSTYNA
Published: September 2024

Abstract: The article addresses the issue of using the emancipatory-participatory paradigm in the process of reconstructing the experience of wartime childhood, that is, experiencing formative years in the circumstances of armed conflict. Adopting the specific idiographic case of the Museum of Wartime Childhood in Sarajevo, the author analyzes the local socio-cultural context, methodological assumptions, as well as forms of realization of the mission of the Museum of Wartime Childhood in Sarajevo, which is to legitimize the narratives of those whose voices remain marginalized in the generalized memetic discourse. Such oriented research and educational activities are part of the characteristics of emancipatory and advocacy approaches to participatory research, the specificity of which is also the subject of the analyses of these reflections.
Imperfect Targeting and Advertising Strategies
Authors: Karle Heiko , Reisinger Markus
Published: September 2024

The ability to successfully target consumers has been substantially affected by recent developments in digital markets, such as improvements in tracking technologies or General Data Protection Regulation. In this paper, we set up a game theoretic model to examine the implications of such changes in targeting success on firms’ targeting strategies and profits. We explicitly consider that firms can target different consumer groups—that is, high- or low-valuation consumers—and that targeting is imperfect—that is, a firm may not reach the intended consumer. We find that a higher targeting success rate has a nonmonotone effect on firms’ profits—that is, lowering profits if targeting is rather imprecise but raising profits if targeting is relatively accurate. If the probability of successful targeting is low, firms target high-valuation consumers (competition for cherries). More fine-tuned targeting then amplifies competition and decreases profits. Instead, if targeting is sufficiently precise, more fine-tuned targeting increases profits because firms segment the market by targeting different consumer groups. Improvements in the targeting ability also have profound effects on the number of products a firm offers and on the profitability of offering products that appeal not only to a single consumer group. First, although increased targeting success raises the attractiveness of introducing an additional product, it also heats up competition. A firm may therefore optimally reduce the number of products it sells if targeting success increases. Second, if products have a broader appeal, market segmentation is more likely to occur. However, aggregate profits are lower compared with when products are narrow.

This paper was accepted by Joshua Gans, business strategy.

Funding: Financial support from the German Research Foundation [DFG Project 462020252] is gratefully acknowledged.

Supplemental Material: The online appendices are available at https://doi.org/10.1287/mnsc.2023.03632 .
Social work with a foster family for the elderly: specifics and technologies
Authors:   State Institution Luhansk Taras Shevchenko National University, Krasnovа Nataliia
Published: September 2024

This article characterizes the problem of the aging of the modern population as a global social phenomenon that affects all areas of the life path of the elderly; categories of elderly people in need of social assistance are defined (lonely people of retirement age; people deprived of the care of close relatives; elderly people with full or partial loss of working capacity, self-care skills; those experiencing problems with independent movement, meeting needs) and their problems: psychological discomfort; the feeling of one's uselessness; despair from helplessness and loneliness; bad health, etc. The specifics of the foster family, which is created for single or living alone elderly people who need permanent or temporary external assistance due to partial or complete loss of the ability to independently meet their basic life needs, are revealed. The specifics of the foster family as an innovative technology of social work are given: positive (professionalism of social work specialists, comprehensive work with candidates to create a foster family, reassessment of family values, connection of generations, etc.) and negative (insufficient development of technology, lack of psychological work with candidates before starting a family, insufficient awareness of the existence of this technology among the population, etc.) factors of social work with foster families for the elderly.
Communicative portrait of the online teacher of the English language and translation studies at higher education institutions
Authors:   State Institution Luhansk Taras Shevchenko National University, Perova Svitlana , Krisalo Olha ,   State Institution Luhansk Taras Shevchenko National University
Published: September 2024

The article presents the results of the analysis of the communicative portrait of the online teacher of the English language and translation studies at a higher education institution, which was conducted in the context of digitalisation of education in the context of glocalisation. As a result of the analysis of the attended practical classes in various disciplines related to the study of English and translation studies, which were conducted in a distance format, four components of the professional communicative portrait of the online teacher of English and translation studies at a higher education institution have been identified: virtual communicative portrait, non-verbal communicative portrait, psychological and cognitive communicative portrait and competence-based communicative portrait. The paper considers their main characteristics and explores the strategies that underlie the creation of each of the portraits. The research was conducted in the context of studying online learning as a special form of communication between a teacher of English and translation studies and higher education students, which takes place distantly with the help of information technologies. The use of these technologies can transform the emotional, mental and motivational components of the human personality, which is multimodal, and provide the opportunity to use different ways of presenting new information, making education more inclusive and accessible. Speaking about methodological support for an educational institution, the authors take into account the trend towards glocalisation of educational programmes aimed at creating meaningful connections between the global context and local culture, which makes education relevant and meaningful for students. The analysis allowed not only to form the holistic view of the digital communicative portrait of the online teacher of English and translation studies at a higher education institution, but also to record the modern requirements for a teacher working in the era of digitalisation, glocalisation and the development of distance learning.
Means of supporting clients' motivation to change in consultative interaction with a psychologist
Authors:   State Institution Luhansk Taras Shevchenko National University, Pashko Tetiana , Glichenko Olena ,   State Institution Luhansk Taras Shevchenko National University
Published: September 2024

The article examines the problem of effectiveness of the psychological counseling process as a specific type of activity of a psychologist, which can be achieved due to specially organized psychological support in motivation of clients to change, as a certain readiness of a person to change the usual ways of life in order to achieve the desired goal. The article analyzes modern views on the task of a psychologist in the course of psychological counseling, describes the current trends and challenges of specialists. The article presents an analysis of the concept of a motivational system and a client's motivational field, their components and features are highlighted. The stages and factors of the process of changing human behavior are described, recommendations are given for the psychologist's actions in accordance with each stage and the conditions for the effectiveness of this process. The authors rely on the theories of behavior changes by James O. Prohaska and Carlo Di Clemente and V. Yaltonskyi. The article analyzes the processes that should be specially organized by the psychologist in order to support the client's motivation to change. The authors attributed to them the development of the client's expectations, the client's meaningful assessment of the costs to achieve the goal, resistance as a natural process of consultative interaction. The article analyzes the conditions that will make it possible to build a working alliance between the client and the psychologist in a consultative interaction and maintain the level of motivational tension sufficient for the client's readiness to implement the desired changes in his life. Separately, the article describes the principles of organizing consultative interaction, which will provide the client with the opportunity to realize his own motives and move forward to achieve the desired changes in his life.
Peculiarities of studying fonts with students of art universities (on the example of the Ukrainian font “Ruthenia”)
Authors:   State Institution Luhansk Taras Shevchenko National University, Sobolevskyi Oleksii
Published: September 2024

The article examines the current relevant problems that come with teaching the subject of «Fonts» art major students in higher educational institutions of Ukraine. Extra special attention is paid to the study of the history of the emergence and individual stages of the reformation of the Cyrillic script among the Eastern Slavic nations. The main topic of the study is the relevance of creating a national font that visually reflects all the specific special features of the modern Ukrainian language. The attention is focused on a problem that has existed for more than 300 years – the halting of the gradual development of the Cyrillic by the font reform of Peter the Great, which was introduced in 1708–1710. We must remember that written letters are not only a reflection of language’s sounds, but also a reflection of our history and cultural heritage. The article examines the main historical stages of the development of the alphabet, gives a brief overview and descriptions of the writing styles: ustav, semi – ustav, skoropis and vyaz. Special attention is given to the introduction to the font designs of the Ukrainian calligrapher, professor Vasyl Yakovych Chebanyk, who has been studying and improving the national Ukrainian alphabet for half a century. Vasyl Yakovych's graphic font designs are based on an in – depth study of the historical conditions for the emergence and development of the Slavic writing and the specifics of its evolution. Deeply concerned about the future of the Ukrainian alphabet, the artist makes his suggestions for changes in the design of the modern Cyrillic alphabet, which is unfortunately still a type of «civil font» from the time of Peter the Great’s reform. The new Ukrainian font developed by Vasyl Yakovych Chebanyk was named «Ruthenia» and is gradually entering our everyday life. Some official state institutions are already starting to use them, schoolchildren in junior grades write letters based on samples of the new font. When teaching, special attention should be paid to the uniqueness of Ukrainian fonts and their spread among Ukrainian society.
Embodiment in Anthropological Epigenetics Research
Authors: Saboowala Sana , Wilson Meredith A. , Vilchis Sahara Z. , Rogers-LaVanne Mary P.
Published: September 2024

abstract: This article reviews literature in human epigenetic research as a case study in order to examine and critique the dominant framework of embodiment as unidirectional or bidirectional and mechanistically driven. The authors identify three major critiques to this approach: (1) the treatment of epigenetic traits as a mechanism of embodiment, rather than as multidirectional components of a dynamic and ongoing embodiment process; (2) a tendency to view changing epigenetic traits as both the cause and the solution for embodied social inequalities rather than examining the need for systemic change; and (3) a loss of the complexity of varied lived experiences within epigenetic studies. The authors suggest weaving in humanistic frameworks and expanding toward a multidirectional definition of embodiment in the field as a way forward.
My Women
Authors: Iliukha Yuliia
Published: September 2024

Abstract: This nonfiction story follows a woman living in a war-torn environment and the fears of living in these conditions. The story explores loneliness, fear, vulnerability, and the impact of war.
Learning to Live as a Force of Nature
Authors: Brems Makella
Published: September 2024

Abstract: The essay contrasts the difference between urban life in Manhattan to the rural farmlands of Boulder, Colorado. Through working on a farm and reexperiencing the natural world, the author finds a deeper connection to nature, fostering a feeling of self-awareness. The author reflects on the transition from philosophy to science, where the understanding of nature's purpose changed from antiquity to the modern era. In a world dominated by technology and industry, sustainable farming and ecological practices can reconnect people with nature, promoting mindfulness and natural harmony.
From Benevolence
Authors: Bayeza Ifa
Published: September 2024

Abstract: The two-act drama explores the transformation in the Mississippi Delta in the wake of the death of Emmett Louis Till, the Chicago teenager who was murdered in the summer of 1955. Benevolence explains the toll of the legacy of enslavement on individuals and families. It tells the story of two women, the men in their lives, and their experiences during this time.
Improved tracking of corneal immune cell dynamics using in vivo confocal microscopy
Authors: Bedggood Phillip , Wu Mengliang , Zhang Xinyuan , Rajan Rajni , Wu Ching Yi , Karunaratne Senuri , Metha Andrew B. , Mueller Scott N. , Chinnery Holly R. , Downie Laura E.
Published: September 2024

In vivo confocal microscopy (IVCM) is a widely used technique for imaging the cornea of the eye with a confocal scanning light ophthalmoscope. Cellular resolution and high contrast are achieved without invasive procedures, suiting the study of living humans. However, acquiring useful image data can be challenging due to the incessant motion of the eye, such that images are typically limited by noise and a restricted field of view. These factors affect the degree to which the same cells can be identified and tracked over time. To redress these shortcomings, here we present a data acquisition protocol together with the details of a free, open-source software package written in Matlab. The software package automatically registers and processes IVCM videos to significantly improve contrast, resolution, and field of view. The software also registers scans acquired at progressive time intervals from the same tissue region, producing a time-lapsed video to facilitate visualization and quantification of individual cell dynamics (e.g., motility and dendrite probing). With minimal user intervention, to date, this protocol has been employed to both cross-sectionally and longitudinally assess the dynamics of immune cells in the human corneal epithelium and stroma, using a technique termed functional in vivo confocal microscopy (Fun-IVCM) in 68 eyes from 68 participants. Using the custom software, registration of ‘sequence scan’ data was successful in 97% of videos acquired from the corneal epithelium and 93% for the corneal stroma. Creation of time-lapsed videos, in which the averages from single videos were registered across time points, was successful in 93% of image series for the epithelium and 75% of image series for the stroma. The reduced success rate for the stroma occurred due to practical difficulties in finding the same tissue between time points, rather than due to errors in image registration. We also present preliminary results showing that the protocol is well suited to in vivo cellular imaging in the retina with adaptive optics scanning laser ophthalmoscopy (AOSLO). Overall, the approach described here substantially improves the efficiency and consistency of time-lapsed video creation to enable non-invasive study of cell dynamics across diverse tissues in the living eye.
Affordable ultra-widefield smartphone PedCam for comprehensive pediatric retinal examination
Authors: Rossi Alfa , Toslak Devrim , Erol Muhammet Kazim , Rahimi Mojtaba , Son Taeyoon , Chan R. V. Paul , Yao Xincheng
Published: September 2024

Widefield fundus photography is critical for the detection, documentation, and management of pediatric eye diseases. Existing clinical pediatric fundus cameras offer a limited field of view (FOV) and suboptimal image contrast, hindering comprehensive peripheral retina examination. Additionally, the high cost and lack of portability of commercial devices restrict their use in resource-limited settings. We introduce a cost-effective smartphone-based pediatric camera (PedCam) that provides a 180° eye angle (126° visual angle) snapshot FOV. Utilizing trans-pars planar illumination, the device enables nonmydriatic imaging by allocating the pupil exclusively for imaging, eliminating the need for pharmacological pupillary dilation. By adjusting the optical axis of the PedCam relative to the ocular axis, the effective FOV can be expanded up to 240° eye angle (180° visual angle), enabling complete retinal evaluation. This innovative smartphone PedCam represents a significant advancement in affordable telemedicine for the screening, monitoring, and management of retinopathy of prematurity and other pediatric eye conditions.
Co-axial superposition: generation of perfect vortex beams with multi-openings and adjustable spherical symmetry
Authors: Hussain Anwar , Zhou Meiling , Zhou Yuan , Li Runze , Peng Tong , Yan Shaohui , Min Junwei , Dan Dan , Yao Baoli
Published: September 2024

The perfect vortex beam, with a diameter that remains independent of the topological charge, has numerous applications in far-field information propagation. In this study, a hologram is obtained through the co-spiral superposition of two primary spiral axicons which is assigned to spatial light modulator for the generation of perfect vortex beams. Key parameters such as the topological charge and intra-ring spacing of individual spiral axicons play critical roles in controlling the characteristics of the resulting perfect vortex beam through the resultant hologram. By adjusting these parameters, precise control can be exerted over the number of openings in the beam and the diameter of the central dark area of the beam. The generation of the entire family of vortex beams with both odd and even numbers of openings in both symmetrical and asymmetrical geometry of the vortex beam petals is presented in simulation and experiment. The perfect vortex beam reported here is characterized by its adjustable number of openings and controllable petal size, holding significant potential for applications in optical trapping. The existence of multiple circular vortex petals with different radii is expected to enable the optical sorting of different particles.
High efficiency high brightness spectral beam combination based on an ultra-broad area laser diode stack
Authors: Zhang Xiaoming , Wang Xiaojun , Zong Nan , Li Xuepeng , Zhang Aonan , Guo Yading , Liu Ke , Yang Jing , Cui Dafu , Xu Zuyan
Published: September 2024

We demonstrate what we believe to be for the first time a high efficiency, high brightness laser source by external cavity spectral beam combination (SBC) in the fast axis based on the 1000 µm ultra-broad area laser diode (UBALD). Regarding the slow axis beam quality of UBALD, we propose a feedback model of the slow axis angle energy distribution in the oscillation process. By adding a structure with a filtering effect in the external cavity, both theory and experiment show that the beam quality of the slow axis can be effectively improved. With a 25-emitter UBALD stack, an SBC maximum CW output power reaches up to 730.6 W with an electro-optical efficiency of 63.7%. The SBC spectrum consists of 25 discrete peaks with a central wavelength of ∼967 nm and an overall spectrum width of 27.2 nm. The beam quality M2 values along the fast and slow axes are measured to be 5.2 and 22.8 at an output power of 623.4 W, corresponding to a brightness as high as 562.3 MW/(cm2•sr).
Absolute testing of optical flats using minimum norm least squares solutions
Authors: Qiao Xiaoyue , Xun Hui , Bai Yunbo , Chen Xin , Liu Shijie , Su Rong
Published: September 2024

A laser Fizeau interferometer measures surface form by comparing the wavefronts reflected from a reference surface and the surface under test. The measurement accuracy is limited by the unknown absolute form error of the reference flat. Absolute testing offers a strategy to break through the limitation. In this work, we propose a three-flat absolute testing method using minimum norm least squares solutions (MNLS). After acquiring three measurement sets from pairwise combinations among the flats, one flat is rotated by 90° or 180° for the fourth measurement. The simulation demonstrates the effectiveness of the proposed MNLS method and its robustness against rotational angle errors. Our absolute testing method is experimentally validated using a home-built and a commercial Fizeau interferometers. Correcting the absolute forms of the home-built Fizeau interferometer’s reference flat improves its measurement accuracy. The experimental outcomes of the MNLS absolute testing technique are compared with two alternative absolute testing methods. The MNLS method’s advantage is demonstrated.
Compact advanced pure tilt actuator for testing tilt-to-length coupling in space-based gravitational wave detection
Authors: Lin Xiang , Yan Hao , Miao Hai-Xing , Qiu Peng , Liang Yu-Rong , Yeh Hsien-Chi , Zhou Ze-Bing
Published: September 2024

Tilt-to-length (TTL) coupling, caused by the jitter of test masses or satellites, is a major noise source in space-based gravitational wave detection. Calibrating and suppressing TTL coupling noise at the sub-nanometer level is essential. A key challenge in current ground-based TTL coupling testing is the residual translational movement of the tilt actuator. This paper presents the development of a compact advanced pure tilt actuator (APTA) specifically designed for testing TTL coupling. The APTA enables precise tilt motion, monitored by a four-beam interferometer measuring the displacement of attached retroreflectors. Detailed theoretical models and experimental setups are given. Experimental results demonstrate that the APTA test bed can achieve sub-nanometer-level TTL coupling calibration. Additionally, a typical test-mass interferometer tested by the APTA test bed demonstrated that the imaging system effectively suppresses TTL coupling errors. The TTL coupling coefficients were reduced from over ±30 μm/rad to within ±5 μm/rad across a range of ±200 μrad. The APTA test bed offers a compact, high-precision solution for ground-based TTL coupling tests and has the potential for broader application in related experimental setups.
Orthogonality of polarization superposition based on polarization holography
Authors: Xu Xianmiao , Zheng Shujun , Ke Shenghui , Liu Hongjie , Jin Junchao , Li Zhengyu , Chen Xueyan , Yang Yi , Zheng Jihong , Li Xiong , Cao Qiang , Tan Xiaodi
Published: September 2024

We propose a polarization superposition orthogonal theory based on tensor polarization holography. Based on this theory, the holographic multiplexing capability can be improved measurably. The orthogonality of polarization waves is characterized by the null reconstruction in polarization holography, achieved through the superposition of multiple basic polarization reference waves. This paper analyzes the orthogonality of linear polarization wave superposition and circular polarization wave superposition using the tensor polarization holography theory. Using the polarized holography multiplexing technique, we experimentally verify the orthogonality of polarization wave superposition. Our experimental results align with the theoretical analysis, indicating potential applications in polarization encoding and decoding by this theory, thereby diversifying optical encryption technology Additionally, we demonstrate that polarization superposition orthogonality holds significant promise for optical control technology.
Virtual orbital angular momentum-based phase clock
Authors: Zhang Lei , Yu Benli
Published: September 2024

A virtual orbital angular momentum (VOAM)-based phase clock is introduced to achieve phase variation metrology, which can be utilized in various conventional interferometry applications. Digital wavefronts possessing VOAM are employed in interference data processing, wherein phase change measurement is converted into image azimuth calculations. With a Moiré technique and a virtual fractional topological charge of l=0.5, a “phase clock” is depicted on a circular dial with a rotational probe indicating the phase change and a stationary probe addressing period ambiguity. The natural 360° reference of the rotation azimuth and the benchmark function of the stationary probe inherently ensure high precision. In the absence of actual OAM beam involvement, this technique harnesses all the benefits of previously reported OAM-based interferometers while overcoming many technological constraints. Factors that disrupt the rotational symmetry of the interferogram are acceptable. Therefore, the method is immune to system errors, alignment errors, and even non-uniformities in the target object under test across the entire aperture. Large-range measurements are attainable due to the stationary probe’s period counting, and remote measurements are feasible without concerns regarding the stability of fractional topological charge propagation. Notably, the phase clock with l=0.5 offers the highest sensitivity to date. This approach can be seamlessly integrated into various traditional interferometers through a straightforward expansion module, incurring zero additional hardware expenses. High resolution can even be achieved with the naked eye. Experiment validation is presented in the form of a displacement measurement interferometer and a temperature sensor. This method introduces a novel paradigm that utilizes OAM for precise interferometry while addressing its inherent limitations.
Role of sleep problem on suicidal behaviour and non-suicidal self-injury among adolescents in Pokhara, Nepal
Authors: Thapa Seema , Yadav Dipendra Kumar
Published: September 2024

Introduction

Sleep is a fundamental human requirement, considered one of the major contributing factors to physical and mental health, especially among adolescents. Poor quality sleep has many potential consequences including non-suicidal self-injury (NSSI), suicidal thoughts or behaviour and complete suicide. The NSSI and suicidal behaviour are increasing in Nepal. Thus, this study aimed to assess the role of sleep problem on suicidal behaviour and non-suicidal self-injury among adolescents in Pokhara metropolitan, Nepal.

Methods

A cross-sectional analytical study was conducted among 673 adolescents using a multistage cluster sampling technique from private and public schools in Pokhara Metropolitan. Self-administered questionnaire was used for data collection. Collected data was entered and managed in EpiData (version 3.1) and analysed in IBM SPSS (version 23). Binary logistic regression was used to identify the association of sleep problem with NSSI and suicidal behaviour.

Results

The study found that sleep problem (65.2%, 439), suicidal behaviour (18.6%, 125) and NSSI (57.9%, 390) were prevalent among adolescents in study setting. The presence of sleep problem significantly influenced the suicidal behavior (AOR = 3.88, 95% CI = 2.27–6.63) alongside the sex of student (AOR = 1.96, 95% CI = 1.28–3.00), adolescents from family having monthly income less than NPR 40,000 (AOR = 1.97 95% CI = 1.16–3.35) and private schools students (AOR = 2.99, 95% CI = 1.84–4.86). Likewise, sleep problem was also associated with non-suicidal self-injury (AOR = 3.24, 95% CI = 2.26–4.65), in addition to attending private school (AOR = 2.52, 95% CI = 1.71–3.72).

Conclusion

This study concludes that sleep problem is prevalent among the adolescents and increase the risk of NSSI and suicidal behaviour. Therefore, parents and teachers need to assess their conditions and help them maintain sound sleep. Additionally, suicide prevention strategies need to be adopted to mitigate further risk.
Response of blueberry photosynthetic physiology to light intensity during different stages of fruit development
Authors: Long Jia , Tan Tianyu , Zhu Yunzheng , An Xiaoli , Zhang Xinyu , Wang Delu
Published: September 2024

To investigate the response of blueberry photosynthetic physiology to different light intensities during different stages of fruit development. In this study, four light intensity treatments (25%, 50%, 75% and 100% of full light) were set up to study the change rule of photosynthetic pigment content and photosynthetic characteristics of ’O’Neal’ southern highbush blueberry leaves during the white fruiting stage (S1), purple fruiting stage (S2) and blue fruiting stage (S3) under different light intensity environments, and to explore the light demand and light adaptability of blueberry during different developmental stages of the fruit. The results showed that the chlorophyll and carotenoid contents of blueberry leaves showed an increasing trend with decreasing light intensity at all three stages of fruit development. The total chlorophyll content of blueberry leaves at 25% light intensity increased by 76.4% compared with CK during the blue fruiting stage; the maximum net photosynthetic rate (Pmax), light compensation point (LCP), light saturation point (LSP), rate of dark respirations (Rd), inter-cellular CO2 concentration (Ci), stomatal conductance (Gs), transpiration rate (Tr), net photosynthesis rate (Pn), and chlorophyll a/b showed a decreasing trend with decreasing light intensity. The Pn of blueberry leaves was highest under full light conditions at all three stages, and the Pn at 25% light intensity decreased by 68.5% compared with CK during the white fruiting stage Reflecting the fact that blueberries can adapt to low-light environments through increases in chlorophyll and carotenoids, but reduced light intensity significantly inhibited their photosynthesis. The photosynthetic physiology of blueberry showed a consistent pattern at all three stages, but there were some differences in the changes of photosynthetic parameters at different stages. The results of the study can provide theoretical references for the selection of sites and density regulation in blueberry production.
Impact of COVID-19 on psychological distress in subsequent stages of the pandemic: The role of received social support
Authors: Kaniasty Krzysztof , van der Meulen Erik
Published: September 2024

This longitudinal study examined a sample of adult Poles (N = 1245), who were interviewed three times from July 2021 to August 2022, during the later stages of the COVID-19 pandemic. The study had two primary objectives. The first was to assess the impact of the pandemic on psychological distress, measured through symptoms of depression and anxiety. The pandemic’s effects were evaluated using three predictors: direct exposure to COVID-19, COVID-19 related stressors, and perceived threats from COVID-19. The second objective was to investigate the role of received social support in coping with the pandemic’s hardships. Receipt of social support was measured by both the quantity of help received and the perceived quality of that support. A Latent Growth Curve Model (LGCM) was employed to analyze psychological distress across three waves, controlling for sociodemographic variables, non-COVID life events, coping self-efficacy, and perceived social support. Findings indicated that COVID-19 stressors and COVID-19 threats were strongly and consistently associated with greater psychological distress throughout the study period. The impact of direct COVID-19 exposure was limited. The quantity of received support predicted higher distress, whereas higher quality of received support was linked to better mental health. Crucially, the relationship between the quantity of support and distress was moderated by the quality of support. Effective social support was associated with the lowest distress levels, regardless of the amount of help received. Conversely, receiving large amounts of low-quality support was detrimental to psychological health. In summary, the ongoing psychosocial challenges of COVID-19 significantly eroded mental health, highlighting the importance of support quality over quantity in coping with significant life adversities.
Adaptive QP algorithm for depth range prediction and encoding output in virtual reality video encoding process
Authors: Yang Hui , Liu Qiuming , Song Chao
Published: September 2024

In order to reduce the encoding complexity and stream size, improve the encoding performance and further improve the compression performance, the depth prediction partition encoding is studied in this paper. In terms of pattern selection strategy, optimization analysis is carried out based on fast strategic decision-making methods to ensure the comprehensiveness of data processing. In the design of adaptive strategies, different adaptive quantization parameter adjustment strategies are adopted for the equatorial and polar regions by considering the different levels of user attention in 360 degree virtual reality videos. The purpose is to achieve the optimal balance between distortion and stream size, thereby managing the output stream size while maintaining video quality. The results showed that this strategy achieved a maximum reduction of 2.92% in bit rate and an average reduction of 1.76%. The average coding time could be saved by 39.28%, and the average reconstruction quality was 0.043, with almost no quality loss detected by the audience. At the same time, the model demonstrated excellent performance in sequences of 4K, 6K, and 8K. The proposed deep partitioning adaptive strategy has significant improvements in video encoding quality and efficiency, which can improve encoding efficiency while ensuring video quality.
No impact of COVID-19 at delivery on maternal mortality or infant adverse birth outcomes in Botswana during the Omicron era
Authors: Banga Jaspreet , Jackson-Gibson Maya , Diseko Modiegi , Caniglia Ellen C. , Mayondi Gloria , Mabuta Judith , Luckett Rebecca , Moyo Sikhulile , Smith-Lawrence Pamela , Mosepele Mosepele , Lockman Shahin , Makhema Joseph , Zash Rebecca , Shapiro Roger
Published: September 2024

SARS-CoV-2 infection during pregnancy was associated with maternal mortality and adverse birth outcomes in the pre-Omicron era, including a stillbirth rate of 5.6% in Botswana. We re-evaluated these outcomes in the Tsepamo Study during the Omicron era. We assessed maternal mortality and adverse birth outcomes for all singleton pregnancies from mid-November 2021 (the start of the Omicron era) to mid-August 2022 at nine Tsepamo sites, among individuals with documented SARS-CoV-2 screening PCR or antigen tests and known HIV status. Of 9,705 women routinely screened for SARS-CoV-2 infection at delivery (64% of deliveries at these sites), 373 (3.8%) tested positive. Women with HIV were as likely to test positive for SARS-CoV-2 (77/1833, 4.2%) as women without HIV (293/6981, 4.2%) (p = 1.0). There were 5 recorded maternal deaths (0.03%), one occurring in a woman with a positive SARS-CoV-2 test result. In contrast, maternal mortality was 3.7% and 0.1% in those with and without SARS-CoV-2, respectively, during the pre-Omicron era. In the Omicron era, there were no differences among infants exposed or unexposed to SARS-CoV-2 in overall adverse birth outcomes (28.1% vs 29.6%; aRR 1.0, 95%CI 0.8–1.1), severe adverse birth outcomes (11.9 vs 10.6%; aRR 1.1, 95%CI 0.8–1.5), preterm delivery (15.1% vs 14.9%; aRR 1.0, 95%CI 0.8–1.3), or stillbirth (1.9% vs 2.3%; aRR 0.8, 95%CI 0.4–1.7). Adverse outcomes among those exposed to both HIV and SARS-CoV-2 were similar to those exposed to HIV alone (31.2% vs. 33.1%; aRR 0.9, 95%CI 0.6–1.3; p = 0.5). Maternal mortality was far lower in Botswana during the Omicron era than in the pre-Omicron era, and adverse birth outcomes were no longer significantly impacted by exposure to SARS-CoV-2 either overall or with HIV co-exposure. Increased population immunity to SARS-CoV-2, less stress on the hospital systems in the Omicron era, and possible differences in viral pathogenicity may combine to explain these findings.