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Guidelines for testosterone replacement therapy (TRT) have been well studied and defined in adults, however, this remains less defined for adolescents and young men. There are a variety of conditions in adolescents and young men that necessitate TRT. These conditions range from genetic etiologies such as Kallmann syndrome and Klinefelter syndrome, to acquired causes such as testicular trauma. Conditions can be broadly classified as hypogonadotropic hypogonadism or hypergonadotropic hypogonadism, depending on whether there are concurrently elevated gonadotropins (follicle-stimulating hormone (FSH) and luteinizing hormone (LH)). The decision to initiate TRT in these cases is multifaceted, contributing to the challenge of formulating clear guidelines. In this review, we utilized online sources such as PubMed and Google Scholar to find relevant literature, using key words such as testosterone therapy, adolescents and hormone replacement and hypogonadism in adolescents. This narrative review explores existing literature on TRT in adolescents and young men, encompassing common etiologies of hypogonadism in this population, available TRT therapies, and management and surveillance protocols. Furthermore, it addresses the evolving field of TRT in transgender youth. This study underscores the necessity for additional clinical investigations to explore emerging TRT therapies and establish clear surveillance guidelines tailored to this population.

Abstract Background Full‐body skin examination (FSE) is fundamental to the diagnosis of cutaneous malignancy but may not always include concealed site examination (CSE). Objectives To determine the approach of international dermatologists to CSE during FSE and examine influencing factors, barriers and attitudes toward CSE. Methods Members of the International Dermoscopy Society were surveyed using an online 12‐question survey disseminated via email. Results There were 706 completed responses among 1249 unique clicks to the survey, representing a completion rate of 56.5%. Fifty‐four percent of respondents reported always examining the breasts, while 52.8%, 18.8%, and 11.8% always examined the scalp, oral, and anogenital mucosa, respectively. The most frequent reason for examining concealed sites was patient concern, whilst common reasons for not examining concealed sites included low incidence of pathology and concern regarding allegations of sexual misconduct. Conclusions Our findings allude to the need for international consensus guidelines regarding the conduct and inclusion of concealed or sensitive sites in routine FSE. This is essential to define clinician responsibilities, inform patient expectations of care, and thereby mitigate potential medicolegal repercussions.

BackgroundThe revolution of orthopedic implant manufacturing is being driven by 3D printing of titanium implants for large bony defects such as those caused by diabetic Charcot arthropathy. Unlike traditional subtractive manufacturing of orthopedic implants, 3D printing fuses titanium powder layer-by-layer, creating a unique surface roughness that could potentially enhance osseointegration. However, the metabolic impairments caused by diabetes, including negative alterations of bone metabolism, can lead to nonunion and decreased osseointegration with traditionally manufactured orthopedic implants. This study aimed to characterize the response of both healthy and diabetic primary human osteoblasts cultured on a medical-grade 3D-printed titanium surface under high and low glucose conditions.MethodsBone samples were obtained from six patients, three with Type 2 Diabetes Mellitus and three without. Primary osteoblasts were isolated and cultured on 3D-printed titanium discs in high (4.5 g/L D-glucose) and low glucose (1 g/L D-Glucose) media. Cellular morphology, matrix deposition, and mineralization were assessed using scanning electron microscopy and alizarin red staining. Alkaline phosphatase activity and L-lactate concentration was measured in vitro to assess functional osteoblastic activity and cellular metabolism. Osteogenic gene expression of BGLAP, COL1A1, and BMP7 was analyzed using reverse-transcription quantitative polymerase chain reaction.ResultsDiabetic osteoblasts were nonresponsive to variations in glucose levels compared to their healthy counterparts. Alkaline phosphatase activity, L-lactate production, mineral deposition, and osteogenic gene expression remained unchanged in diabetic osteoblasts under both glucose conditions. In contrast, healthy osteoblasts exhibited enhanced functional responsiveness in a high glucose environment and showed a significant increase in osteogenic gene expression of BGLAP, COL1A1, and BMP7 (p

The computational capabilities of near-term quantum computers are limited by the noisy execution of gate operations and a limited number of physical qubits. Hybrid variational algorithms are well-suited to near-term quantum devices because they allow for a wide range of tradeoffs between the amount of quantum and classical resources used to solve a problem. This paper investigates tradeoffs available at both the algorithmic and hardware levels by studying a specific case – applying the Quantum Approximate Optimization Algorithm (QAOA) to instances of the Maximum Independent Set (MIS) problem. We consider three variants of the QAOA which offer different tradeoffs at the algorithmic level in terms of their required number of classical parameters, quantum gates, and iterations of classical optimization needed. Since MIS is a constrained combinatorial optimization problem, the QAOA must respect the problem constraints. This can be accomplished by using many multi-controlled gate operations which must be decomposed into gates executable by the target hardware. We study the tradeoffs available at this hardware level, combining the gate fidelities and decomposition efficiencies of different native gate sets into a single metric called the $\textit{gate decomposition cost}$.

Abstract Background and context The scale of land degradation worldwide has led to nearly one billion hectares committed to restoration globally. However, achieving such restoration targets will necessitate complex trade-offs against limited time, competing knowledge, costs, resources and varying stakeholder and societal preferences. Participatory scenarios allow a way to identify collaborative solutions for restoration planning and implementation best suited for the local cultures and societies they are tied to. They can be used to navigate uncertainties surrounding future trajectories of restored areas by evaluating trade-offs in outcomes. This research aims to systematically map the evidence on the use of participatory scenarios in restoration planning. We use the following research question: What evidence exists on the use of participatory scenarios in ecological restoration? This is answered by examining the characteristics of the evidence base, types of study design, types of outcomes, trade-offs in outcomes, and the role of participants. Methods A comprehensive and reproducible search strategy was followed using bibliographic databases, web-based searches, and targeted searching. Search results underwent a two-step screening process according to eligibility criteria. Metadata on key areas of interest were extracted from included texts and were narratively synthesised alongside data visualisations to answer the research questions. Review findings 18,612 records were initially identified, and 106 articles were included in the final map. Most studies were conducted in Europe and North America, focusing on restoring agricultural land or forests. Most texts used mixed methods and explored multiple outcome types, but environmental outcomes were the most assessed. Within environmental outcomes, indicators for ecological function were assessed more frequently than structural or compositional indicators. The most common reason for choosing outcomes and indicators was stakeholder interest. Trade-offs in social, ecological, and economic outcomes were mainly examined across space using mapping techniques, while far fewer studies looked at trade-offs across stakeholders and time. Participants were mostly included in the scenario creation step and were usually chosen purposefully by the research team. Conclusions It is difficult to understand how useful scenarios are for restoration planning because few texts reported how scenarios fed into the process. Despite this, the range of outcomes used and different method types adopted suggests participatory scenarios allow for integrating different knowledge and approaches, alongside facilitating the use of qualitative or semi-quantitative data when this is more appropriate or quantitative data is not widely available. To better use participatory scenarios as a tool for ecological restoration planning, decision-makers can push for greater levels and definitions of participation from the offset of restoration projects with specified, regular, and structured communication and participation channels. We also recommend more systematic methods of participant selection, such as stakeholder analysis. Further research is needed to understand the effectiveness of participatory scenarios in restoration planning and whether the participation of stakeholders was successful in meeting objectives. To improve the evidence base, future studies should clearly evaluate their effectiveness in the restoration planning process and their success in meeting their participatory objectives.

Abstract Background Interactions among topologically associating domains (TADs), and between the nuclear envelope (NE) and lamina-associated domains (LADs) are expected to shape various aspects of three-dimensional (3D) chromatin structure and dynamics; however, relevant genome-wide experiments that may provide statistically significant conclusions remain difficult. Results We have developed a coarse-grained dynamical model of D. melanogaster nuclei at TAD resolution that explicitly accounts for four distinct epigenetic classes of TADs and LAD–NE interactions. The model is parameterized to reproduce the experimental Hi-C map of the wild type (WT) nuclei; it describes time evolution of the chromatin over the G1 phase of the interphase. The simulations include an ensemble of nuclei, corresponding to the experimentally observed set of several possible mutual arrangements of chromosomal arms. The model is validated against multiple structural features of chromatin from several different experiments not used in model development. Predicted positioning of all LADs at the NE is highly dynamic—the same LAD can attach, detach and move far away from the NE multiple times during interphase. The probabilities of LADs to be in contact with the NE vary by an order of magnitude, despite all having the same affinity to the NE in the model. These probabilities are mostly determined by a highly variable local linear density of LADs along the genome, which also has the same strong effect on the predicted positioning of individual TADs -- higher probability of a TAD to be near NE is largely determined by a higher linear density of LADs surrounding this TAD. The distribution of LADs along the chromosome chains plays a notable role in maintaining a non-random average global structure of chromatin. Relatively high affinity of LADs to the NE in the WT nuclei substantially reduces sensitivity of the global radial chromatin distribution to variations in the strength of TAD–TAD interactions compared to the lamin depleted nuclei, where a small (0.5 kT) increase of cross-type TAD–TAD interactions doubles the chromatin density in the central nucleus region. Conclusions A dynamical model of the entire fruit fly genome makes multiple genome-wide predictions of biological interest. The distribution of LADs along the chromatin chains affects their probabilities to be in contact with the NE and radial positioning of highly mobile TADs, playing a notable role in creating a non-random average global structure of the chromatin. We conjecture that an important role of attractive LAD–NE interactions is to stabilize global chromatin structure against inevitable cell-to-cell variations in TAD–TAD interactions.

Category: Basic Sciences/Biologics; Ankle Arthritis Introduction/Purpose: The first stage of fracture healing consists of hematoma formation with recruitment of proinflammatory cytokines and matrix metalloproteinases. Unfortunately, when there is an intra-articular fracture, these inflammatory mediators are not retained at the fracture site, but instead, bathe the healthy cartilage of the entire joint via the synovial fluid fracture hematoma (SFFH). These inflammatory cytokines and matrix metalloproteinases are known factors in the progression of osteoarthritis and rheumatoid arthritis. Despite the known inflammatory contents of the SFFH, little research has been done on the effects of the SFFH on healthy cartilage with regard to cell death and alteration in gene expression that could lead to post- traumatic osteoarthritis (PTOA). Methods: SFFH was collected from 12 patients with intraarticular ankle fracture at the time of surgery. Separately, human chondrocytes were three-dimensionally cultured to create scaffold -free cartilage tissue analogues (CTAs) to simulate articular cartilage. Experimental CTAs (n=12) were exposed to 100% SFFH for 3 days, washed, and transferred to complete media for 3 days. Control CTAs (n=12) were simultaneously cultured in complete medium. Subsequently, CTAs were harvested and underwent biochemical, histological, and gene expression analysis. Results: Exposure of CTAs to ankle SFFH 3 days significantly decreased chondrocyte viability by 34% (p = .027). Gene expression of both COL2A1 and SOX9 were significantly decreased after exposure to SFFH (p= .012 and p=.0013 respectively). COL1A1 expression trended upward in the SFFH exposure group while there was no difference in RUNX2 and MMP13 gene expression. Quantitative analysis of Picrosirius red staining demonstrated increased collagen I deposition with poor ultrastructural organization in SFFH exposed CTAs. Conclusion: Exposure of an organoid model of healthy cartilage tissue to SFFH after intraarticular ankle fracture resulted in decreased chondrocyte viability, decreased expression of genes regulating normal chondrocyte phenotype, and altered matrix ultrastructure indicating differentiation toward an osteoarthritis phenotype.

Background and objective—Obesity is a prevalent health concern that notably impairs male fertility through hormonal disruptions and other pathophysiological alterations. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) can significantly reduce weight. This narrative review synthesizes the existing literature discussing the impact of glucagon-like peptide-GLP-1 RAs on the male reproductive system, particularly on the hypothalamic–pituitary–gonadal axis and spermatogenesis, highlighting their potential impact on male fertility. Material and methods—PubMed database was used for the retrieval of English-language articles published up to November 2023. This non-systematic literature review predominantly concentrates on both pre-clinical and clinical studies pertaining to GLP-1 RAs, specifically exploring their impact on male reproductive hormones and sperm parameters. Results—GLP-1 receptors have been identified within the male reproductive system according to the existing literature. While the exact mechanisms are not well understood, they appear to be involved in glucose homeostasis and energy metabolism, both vital processes in spermatogenesis. Multiple clinical trials have demonstrated the efficacy of GLP-1 RAs for promoting weight loss. Recent studies show that the use of GLP-1 RAs in obese males may enhance sperm metabolism, motility, and insulin secretion in vitro, along with positive effects on the human Sertoli cells. Recent clinical trials discussed in this review demonstrate weight loss associated with GLP-1 RAs is correlated with improvements in sperm count, concentration, and motility. However, the direct impact of GLP-1 RAs on male reproductive hormones remains unclear, necessitating further research to confirm their potential role in treating male infertility. Conclusions—This narrative review summarizes the existing literature discussing the potential impact of GLP-1 RA on the male reproductive system, emphasizing their potential therapeutic role in addressing idiopathic infertility in obese men. Despite numerous studies exploring the influence of GLP-1 and GLP-1 RAs on reproductive hormones, testicular function, and spermatogenesis, further clinical trials are crucial to validate initial evidence. Longer follow-up periods are essential to address uncertainties regarding the long-term repercussions and outcomes of GLP-1 RA use. While this holds true, the current literature suggests that GLP-1RAs show promise as a potential therapeutic approach for improving sperm parameters in obese men.

We began as a group of students interested in conducting a service-learning project in rural South Africa. As we prepared, we quickly found ourselves exposed to a broad range of literature and personal testimony regarding campus-community engagement that ranged from glowing praise to outright criticism (Butin, 2010; Handler, 2013). While we had been educated about the importance of student mindsets, equity in the engagement, and long-lasting relationships, we still found ourselves faced with the uncertainties of working with people whom we did not know well, in a place we did not know well, with a project where we were not experts. Furthermore, we were deeply concerned with whether we should even attempt to conduct an international service-learning project for fear of potentially causing harm to the community.

Abstract Males and females with alcohol dependence have distinct mental health and cognitive problems. Animal models of addiction postulate that the underlying neurobiological mechanisms are partially distinct, but there is little evidence of sex differences in humans with alcohol dependence as most neuroimaging studies have been conducted in males. We examined hippocampal and amygdala subregions in a large sample of 966 people from the ENIGMA Addiction Working Group. This comprised 643 people with alcohol dependence (225 females), and a comparison group of 323 people without alcohol dependence (98 females). Males with alcohol dependence had smaller volumes of the total amygdala and its basolateral nucleus than male controls, that exacerbated with alcohol dose. Alcohol dependence was also associated with smaller volumes of the hippocampus and its CA1 and subiculum subfield volumes in both males and females. In summary, hippocampal and amygdalar subregions may be sensitive to both shared and distinct mechanisms in alcohol-dependent males and females.

Nanotwinned metals have exhibited many enhanced physical and mechanical properties. Twin boundaries have recently been introduced into sputtered Al alloys in spite of their high stacking fault energy. These twinned Al alloys possess unique microstructures composed of vertically aligned Σ3(112) incoherent twin boundaries (ITBs) and have demonstrated remarkable mechanical strengths and thermal stability. However, their strain rate sensitivity has not been fully assessed. A modified nanoindentation method has been employed here to accurately determine the strain rate sensitivity of nanotwinned Al–Zr alloys. The hardness of these alloys reaches 4.2 GPa while simultaneously exhibiting an improved strain rate sensitivity. The nanotwinned Al–Zr alloys have shown grain size-dependent strain rate sensitivity, consistent with previous findings in the literature. This work provides insight into a previously unstudied aspect of nanotwinned Al alloys.

Abstract Background It is well recognized that the interphase chromatin of higher eukaryotes folds into non-random configurations forming territories within the nucleus. Chromosome territories have biologically significant properties, and understanding how these properties change with time during lifetime of the cell is important. Chromosome–nuclear envelope (Chr–NE) interactions play a role in epigenetic regulation of DNA replication, repair, and transcription. However, their role in maintaining chromosome territories remains unclear. Results We use coarse-grained molecular dynamics simulations to study the effects of Chr–NE interactions on the dynamics of chromosomes within a model of the Drosophila melanogaster regular (non-polytene) interphase nucleus, on timescales comparable to the duration of interphase. The model simulates the dynamics of chromosomes bounded by the NE. Initially, the chromosomes in the model are prearranged in fractal-like configurations with physical parameters such as nucleus size and chromosome persistence length taken directly from experiment. Time evolution of several key observables that characterize the chromosomes is quantified during each simulation: chromosome territories, chromosome entanglement, compactness, and presence of the Rabl (polarized) chromosome arrangement. We find that Chr–NE interactions help maintain chromosome territories by slowing down and limiting, but not eliminating, chromosome entanglement on biologically relevant timescales. At the same time, Chr–NE interactions have little effect on the Rabl chromosome arrangement as well as on how chromosome compactness changes with time. These results are rationalized by simple dimensionality arguments, robust to model details. All results are robust to the simulated activity of topoisomerase, which may be present in the interphase cell nucleus. Conclusions Our study demonstrates that Chr–NE attachments may help maintain chromosome territories, while slowing down and limiting chromosome entanglement on biologically relevant timescales. However, Chr–NE attachments have little effect on chromosome compactness or the Rabl chromosome arrangement.

OBJECTIVES/GOALS: The goal of the study is to understand how changing the surface roughness of 3D printed Titanium either by processing printed samples or artificially printing rough topography impacts the mechanical and biological properties of the Titanium. METHODS/STUDY POPULATION: Titanium dog bones and discs were printed via laser powder bed fusion. groups were defined as 1. polished, 2.blasted, 4.as built, 4.sprouts and 5.rough sprouts. Roughness was measured with line measurement using a confocal microscope. Tensile testing of dog bones produced stress strain curves. MC3T3 preosteoblast were seeded on discs. Samples were analyzed at 0, 2, and 4 weeks. A cell viability assay and confocal fluorescent microscopy assessed cell growth. Alkaline Phosphatase (ALP) assay and Quantitative Polymerase Chain Reaction (qPCR) examined cell differentiation. Extracellular matrix (ECM) was stained for collagen and calcium. Scanning Electron Microcopy (SEM) was done on sputter coated discs. RESULTS/ANTICIPATED RESULTS: Measured roughness defined by Rz, maximum peak to valley distance of the sample profile ranged from 2.6-65.1 µm. The addition of printed roughness in the sprouts and rough sprouts group significantly diminished ductility resulting in early strain to failure during tensile testing. Cells adhered and proliferated on discs regardless of roughness group. There was no statistical difference in ALP activity, but qPCR showed that rough groups (sprouts and rough sprouts) had diminished Osteocalcin gene expression at week 2 and 4. The ECM in the rough groups was more resistant to repeated washes and was more extensive with SEM. DISCUSSION/SIGNIFICANCE OF IMPACT: Printing roughness diminished mechanical properties without clear benefit to cell growth. Roughness features were on mesoscale, unlike samples in literature on microscale that increase cell activity. Printed topography may aid in implant fixation and not osseous integration as hypothesized. CONFLICT OF INTEREST DESCRIPTION: Dr. Samual Adams, Dr. Ken Gall and Cambre Kelly own stock and/or stock options in restor3d, Inc.

Kevin Barry’s Atlantic Drift. Kevin Barry is a contemporary Irish novelist, short-story writer, dramatist and publisher whose work is set on the island's coastal fringes. This essay is a reading of some stories from There are Little Kingdoms and of his first novel, The City of Bohane. In tracing the importance of liquid and maritime imagery it suggests the importance of a sea-side perspective in his writing, and situates this perspective in wider conversations about ideas of islands and archipelagos. Rezumat. Deriva atlantică a lui Kevin Barry. Kevin Barry este un romancier, nuvelist, dramaturg și publicist contemporan irlandez, a cărui operă este plasată în spațiul de coastă al insulei. Eseul de față este o lectură a unora dintre povestirile din There are Little Kingdoms și al primului său roman, The City of Bohane. Subliniind importanța imaginilor acvatice și maritime, se sugerează importanța unei perspective maritime în scriitura acestuia, plasându-se această perspectivă într-o discuție mai largă despre insule și arhipelaguri. Cuvinte cheie: coastă, arhipelag, apă, estuar, mareic, insulă

Category: Basic Sciences/Biologics Introduction/Purpose: Large osteochondral lesion of the talus (OLT) can be difficult to treat. Although many treatment options exist, fresh osteochondral allograft transplantation has demonstrated promise as the primary treatment for OLTs with substantial cartilage and bone involvement as well as a secondary treatment option after failure of other cartilage repair techniques. Fresh osteochondral allografts are size-matched from organ donors and, in theory, have healthy articular cartilage and bone. However, the quality of allograft cartilage and bone has never been examined with respect to the OLT cartilage and bone being replaced. The purpose of this study was to perform a matched comparison of the cartilage and bone from patients OLTs to the fresh osteochondral allograft replacement. Methods: Discarded intact osteochondral specimens were collected from 8 patients undergoing surgery for an OLT. The specimens included the excised OLT and a portion of the fresh allograft replacement that the same patient received at the time of surgery. Histologic analysis was performed. The safranin-o histology was then scored using the International Cartilage Repair Society (ICRS) histopathology grading and staging system. In this system the grade determines cartilage and bone destruction on a scale of 0 to 6.5, the stage determines the percentage of involvement in the specimen on a scale of 0 to 4, and the total score is the grade multiplied by the stage. The surface roughness was also compared between the OLT and allograft cartilage using ImageJ software (NIH). Paired t-tests were performed on the ICRS grade, stage, and total score, and surface roughness comparing the OLTs and allografts. Significance was set at p

Steroid-sensitive nephrotic syndrome (SRNS) can cause CKD and necessitate kidney transplant. Here the authors identify FAT1 mutations by homozygosity mapping and whole-exome sequencing in families with SRNS and provide functional mouse and zebrafish evidence that FAT1 is required for normal glomerular and tubular function and that FAT1 mutations can cause SRNS.

ABSTRACT This study explores the possibility of using objects, as described in activity theory, as a measure of “needs” in an ESP needs analysis. The objective is to determine the value of a methodological approach which connects the needs of second language learners with the objects of their work. A single ESP user in a multinational company in Colombia was interviewed and the interview data was subjected to qualitative data analysis procedures. The information was then analyzed through the prism of activity theory to determine the user’s objects. In total, the user completed at work many tasks in English which can be summarized by the three objects of Head Office Tasks, Worker tasks, and Brazil Tasks. Activity theory provided rich information in the analysis by focusing on the user’s tasks and personal motivation. This study shows that activity theory can be a tool in an ESP needs analysis procedure but is limited to its description of the user’s perception of their activities. RESUMEN Este estudio explora la posibilidad de utilizar objetos descritos en la teoría de la actividad, como una medida para el análisis de las necesidades en English for Specific Purposes (ESP). El objetivo es determinar el valor de un enfoque metodológico que conecta las necesidades de un segundo idioma del estudiante con los objetos de su trabajo. Fue entrevistado un usuario ESP de una empresa multinacional en Colombia y la información recogida fue sometida a procedimientos de análisis de datos cualitativos, donde fue analizada a través del prisma de la teoría de la actividad para determinar los objetos del usuario. En síntesis, el usuario completó bastantes tareas en inglés, que se pueden resumir en tres objetos como: tareas de jefe de oficina, tareas de los trabajadores y tareas de Brasil. La teoría de la actividad proporciona una rica información en el análisis, centrándose en las tareas del usuario y la motivación personal. Este estudio muestra que esta teoría puede ser una herramienta en una necesidad de análisis ESP, pero se limita a la descripción de la percepción del usuario frente a sus actividades.

The presence of shared interests between politicians and citizens is central to many accounts of political representation, yet there has been little empirical research into how citizens perceive these interests and whether they think a ‘communion of interests’ exists between them and their elected representatives. Using new survey data, this paper explores the extent to which Britons think their Members of Parliament share the same everyday experiences as they do. It further explores the relationship between these perceptions and indicators of specific and diffuse political support. We show that British citizens generally say that politicians are less affected by social and economic conditions and less reliant on public services than they are. The size of this perceived ‘discommunion’ affects voting behaviour and satisfaction with democracy.

Detect and Avoid (DAA) systems are complex communication and locational technologies comprising multiple independent components. DAA technologies support communications between ground-based and space-based operations with aircraft. Both manned and unmanned aircraft systems (UAS) rely on DAA communication and location technologies for safe flight operations. We examined the occurrence and duration of communication losses between radar and automatic dependent surveillance–broadcast (ADS-B) systems with aircraft operating in proximate airspace using data collected during actual flight operations. Our objectives were to identify the number and duration of communication losses for both radar and ADS-B systems that occurred within a discrete time period. We also investigated whether other unique communication behavior and anomalies were occurring, such as reported elevation deviations. We found that loss of communication with both radar and ADS-B systems does occur, with variation in the length of communication losses. We also discovered that other unexpected behaviors were occurring with communications. Although our data were gathered from manned aircraft, there are also implications for UAS that are operating within active airspaces. We are unaware of any previously published work on occurrence and duration of communication losses between radar and ADS-B systems.

Three dimensional nuclear architecture is important for genome function, but is still poorly understood. In particular, little is known about the role of the "boundary conditions"--points of attachment between chromosomes and the nuclear envelope. We describe a method for modeling the 3D organization of the interphase nucleus, and its application to analysis of chromosome-nuclear envelope (Chr-NE) attachments of polytene (giant) chromosomes in Drosophila melanogaster salivary glands. The model represents chromosomes as self-avoiding polymer chains confined within the nucleus; parameters of the model are taken directly from experiment, no fitting parameters are introduced. Methods are developed to objectively quantify chromosome territories and intertwining, which are discussed in the context of corresponding experimental observations. In particular, a mathematically rigorous definition of a territory based on convex hull is proposed. The self-avoiding polymer model is used to re-analyze previous experimental data; the analysis suggests 33 additional Chr-NE attachments in addition to the 15 already explored Chr-NE attachments. Most of these new Chr-NE attachments correspond to intercalary heterochromatin--gene poor, dark staining, late replicating regions of the genome; however, three correspond to euchromatin--gene rich, light staining, early replicating regions of the genome. The analysis also suggests 5 regions of anti-contact, characterized by aversion for the NE, only two of these correspond to euchromatin. This composition of chromatin suggests that heterochromatin may not be necessary or sufficient for the formation of a Chr-NE attachment. To the extent that the proposed model represents reality, the confinement of the polytene chromosomes in a spherical nucleus alone does not favor the positioning of specific chromosome regions at the NE as seen in experiment; consequently, the 15 experimentally known Chr-NE attachment positions do not appear to arise due to non-specific (entropic) forces. Robustness of the key conclusions to model assumptions is thoroughly checked.

Biosensors are analytical devices that have found a variety of applications in medical diagnostics, food quality control, environmental monitoring and biodefense. In recent years, functional nucleic acids, such as aptamers and nucleic acid enzymes, have shown great potential in biosensor development due to their excellent ability in target recognition and catalysis. Deoxyribozymes (or DNAzymes) are single-stranded DNA molecules with catalytic activity and can be isolated to recognize a wide range of analytes through the process of in vitro selection. By using various signal transduction mechanisms, DNAzymes can be engineered into fluorescent, colorimetric, electrochemical and chemiluminescent biosensors. Among them, colorimetric sensors represent an attractive option as the signal can be easily detected by the naked eye. This reduces reliance on complex and expensive equipment. In this review, we will discuss the recent progress in the development of colorimetric biosensors that make use of DNAzymes and the prospect of employing these sensors in a range of chemical and biological applications.

Background and objective—Obesity is a prevalent health concern that notably impairs male fertility through hormonal disruptions and other pathophysiological alterations. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) can significantly reduce weight. This narrative review synthesizes the existing literature discussing the impact of glucagon-like peptide-GLP-1 RAs on the male reproductive system, particularly on the hypothalamic–pituitary–gonadal axis and spermatogenesis, highlighting their potential impact on male fertility. Material and methods—PubMed database was used for the retrieval of English-language articles published up to November 2023. This non-systematic literature review predominantly concentrates on both pre-clinical and clinical studies pertaining to GLP-1 RAs, specifically exploring their impact on male reproductive hormones and sperm parameters. Results—GLP-1 receptors have been identified within the male reproductive system according to the existing literature. While the exact mechanisms are not well understood, they appear to be involved in glucose homeostasis and energy metabolism, both vital processes in spermatogenesis. Multiple clinical trials have demonstrated the efficacy of GLP-1 RAs for promoting weight loss. Recent studies show that the use of GLP-1 RAs in obese males may enhance sperm metabolism, motility, and insulin secretion in vitro, along with positive effects on the human Sertoli cells. Recent clinical trials discussed in this review demonstrate weight loss associated with GLP-1 RAs is correlated with improvements in sperm count, concentration, and motility. However, the direct impact of GLP-1 RAs on male reproductive hormones remains unclear, necessitating further research to confirm their potential role in treating male infertility. Conclusions—This narrative review summarizes the existing literature discussing the potential impact of GLP-1 RA on the male reproductive system, emphasizing their potential therapeutic role in addressing idiopathic infertility in obese men. Despite numerous studies exploring the influence of GLP-1 and GLP-1 RAs on reproductive hormones, testicular function, and spermatogenesis, further clinical trials are crucial to validate initial evidence. Longer follow-up periods are essential to address uncertainties regarding the long-term repercussions and outcomes of GLP-1 RA use. While this holds true, the current literature suggests that GLP-1RAs show promise as a potential therapeutic approach for improving sperm parameters in obese men. [ABSTRACT FROM AUTHOR]