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Locust phase polyphenism is a remarkable example of phenotypic plasticity, driven by population density to produce a dramatic shift between cryptic, solitarious and swarming, gregarious phenotypes. Despite over a century of research, the evidence base lacks systematic synthesis. We conducted a systematic review of 400 studies on locust phase polyphenism, integrating evidence across ecological, neurobiological, physiological, molecular, epigenetic, and microbial drivers. The results revealed that the evidence base is constrained by two critical limitations. First, severe taxonomic narrowness: 93.8% of studies focus on at least one of two model species (desert locust, Schistocerca gregaria and migratory locust, Locusta migratoria), with only 6.2% examining other locust species exclusively. Second, profound methodological disconnect: 84.5% of studies are laboratory-based, while field-only (6.0%) and integrated field-laboratory studies (6.2%) together constitute only 12.2% of the literature. Within this paradigm, mechanistic research has successfully mapped proximate pathways from tactile stimulation and serotonin/dopamine signaling to transcriptomic reprogramming and epigenetic regulation. However, direct species comparisons reveal fundamental divergence rather than conservation, challenging assumptions of universal mechanisms. Laboratory-derived pathways remain poorly integrated with field ecology-vegetation structure, nutritional geography, and climate dynamics-creating a translational impasse for predictive management. Emerging areas such as microbiome dynamics and transgenerational epigenetics require causal validation under ecologically relevant conditions. Reliance on the current narrow paradigm fundamentally limits both biological understanding and practical application. We propose a future research prioritizing: (1) phylogenetically broad comparative multi-omics to distinguish conserved cores from lineage-specific adaptations; (2) integrated field-laboratory experiments incorporating climate and landscape heterogeneity; (3) causal validation of emerging regulators in ecologically relevant contexts; and (4) translation of comparative insights into species-specific management tools through equitable partnerships with researchers and practitioners in outbreak-affected regions. Such integration is essential for developing predictive, sustainable management strategies in an era of global change.

Spinal surgery, particularly spinal decompression and fusion surgery, commonly encounters intraoperative bleeding. Deep bleeding in the narrow operative area (e.g. bone marrow cavity and venous plexus) is a significant challenge for achieving accurate hemostasis with traditional strategies, posing a life-threatening risk. Herein, a novel dual-form hemostatic material (CMC-Gelatin, CG) composed of carboxymethyl cellulose (CMC) and gelatin is developed for non-compressible hemostasis in spinal surgery. For minor bleeding, CG in powder form reduces blood loss by 69.06% within a mouse bleeding model, demonstrating hemostatic efficacy comparable to that of the commercial Surgicel® powder, while exhibiting superior cytocompatibility. Notably, CG powder rapidly forms an injectable gel upon mixing with saline, making it suitable for severe bleeding in a confined space during spinal surgery. Specifically, in a pig paraspinal microvenous hemorrhage model, CG gel exhibits excellent hemostatic performance, reducing blood loss by 78.44% compared with the untreated group. Importantly, CG demonstrated a comparable hemostasis time and reduced blood loss in vivo compared to the commercial Surgiflo®. The designed CG materials exhibit outstanding hemostatic properties in deep, narrow areas, making them a promising hemostatic material in spinal surgery.

The superior mesenteric artery (SMA) syndrome is a rare condition where the third part of the duodenum is compressed between the abdominal aorta and the SMA. It often causes nonspecific upper abdominal symptoms that mimic common problems like gastritis, leading to delays in diagnosis. A 23-year-old woman from central Nepal had 5 years of epigastric pain, nausea, occasional vomiting, acid brash, and gradual weight loss. She was repeatedly treated for gastritis without improvement. Initial ultrasound was normal, and endoscopy showed antral gastritis. Contrast-enhanced CT revealed a very narrow aorto-mesenteric angle (14°) and distance (3.6 mm), confirming SMA syndrome, along with the narrowing of the celiac trunk, thrombosis of the SMA, and signs of pelvic congestion. Conservative treatment failed, and she underwent open duodenojejunostomy. After surgery, her symptoms resolved completely, and she gradually gained weight. This case shows that the SMA syndrome can be missed for years, especially when endoscopy shows only secondary gastritis. Early CT scanning and timely surgery can cure symptoms and prevent prolonged suffering. The SMA syndrome should be considered in young patients with chronic upper abdominal pain, persistent vomiting, and unexplained weight loss. Prompt imaging and surgical management are often needed for lasting recovery.

Halide perovskite quantum dots (HPQDs) are transformative candidates for next-generation optoelectronic devices, owing to their exceptional optoelectronic properties including widely tunable bandgaps, ultrahigh color purity, and solution processability. However, scalable, deterministic synthesis of high-quality HPQDs with simultaneous ultra-narrow emission linewidth and high photoluminescence quantum yield (PLQY) remains a longstanding challenge, fundamentally limited by the mass transfer bottleneck and poor mixing efficiency of conventional laminar microreactors. Here, we report a biomimetic vein-inspired ultrasonic microreactor integrated with sharp-edged microstructure arrays to address this core challenge. Through systematic multiphysics simulations, we quantitatively decode the acoustic-hydrodynamic coupling mechanism in the microreactor, and establish a quantitative structure-performance relationship between microstructure geometry and sonochemical reaction performance. We identify an optimized cylindrical microstructure configuration that synergistically amplifies acoustic streaming and cavitation yield to break laminar boundary layer confinement. Experimental validation confirms the optimized microreactor enables continuous synthesis of high-quality HPQDs with an ultra-narrow full width at half maximum of 23.28 nm and PLQY up to 78.6%, markedly outperforming conventional microfluidic methods. We further elucidate that cavitation-enhanced micromixing enables dynamic supersaturation tuning, driving LaMer-type size-focusing and homogeneous nucleation for exceptional HPQDs monodispersity. This work provides a generalizable, scalable microfluidic strategy for precision synthesis of high-performance optoelectronic nanomaterials, bridging the critical gap between lab-scale research and industrial translation.

Obstructive sleep apnea (OSA) is associated with excess mortality, and readily obtainable biomarkers may support pragmatic risk stratification in OSA, but their comparative and incremental value remains uncertain. We benchmarked inflammation-nutrition indices and TyG-related metabolic indices for mortality risk in adults with questionnaire-defined OSA and evaluated whether these markers improve 5-year all-cause mortality prediction beyond a basic clinical model. We analysed 3,503 adults with questionnaire-defined OSA from the NHANES 2005-2008 and 2015-2018 derivation cohorts. Seven candidate biomarkers were evaluated: TyG, TyG-BMI, TyG-WC, TyG-WHtR, TG/HDL-C, advanced lung cancer inflammation index (ALI), and neutrophil percentage-to-albumin ratio (NPAR). Survey-weighted Cox models and restricted cubic splines were used to characterise mortality associations. Two 5-year all-cause mortality prediction strategies were developed: a tertile-based model (Model 1) and a continuous-scale model (Model 2). Internal validation used bootstrap optimism correction, calibration curves, Brier scores, and decision-curve analysis. Incremental value beyond a prespecified base model was assessed using likelihood-ratio testing, change in AUC, and net reclassification improvement (NRI). External validation was performed in an independent multicenter Chinese cohort of 200 patients from six hospitals. All included patients had at least 5&#x2009;years of observation time from baseline assessment, allowing complete ascertainment of the binary 5-year all-cause mortality endpoint. The externally validated object was the final Base&#x2009;+&#x2009;Combine model, and its performance was assessed alongside the base model using ROC analysis, calibration plots, calibration intercept and slope, Brier score, and decision-curve analysis. During a median follow-up of 57.0&#x2009;months (IQR 33.0-150.0), 293 all-cause deaths occurred in the derivation cohort. Among individual biomarkers, ALI showed the most robust mortality-related signal across analyses, whereas NPAR showed signal in selected single-marker and nonlinear analyses but was less consistent after full multivariable adjustment. TyG-related indices were also variably associated with mortality and contributed mainly within the combined prediction model. In Model 1, the full 7-marker composite model achieved an AUC of 0.735, a bootstrap-corrected AUC of 0.721, and a Brier score of 0.039. In Model 2, the best-performing combined model incorporated TyG-BMI, TyG-WC, TyG-WHtR, TG/HDL-C, and ALI, yielding an AUC of 0.765, a bootstrap-corrected AUC of 0.761, and a Brier score of 0.038. Internal calibration was acceptable for both derivation models, with Model 2 performing better. Decision-curve analysis showed positive net benefit over treat-all and treat-none strategies, with a wider clinically useful threshold range for Model 2. Compared with the base model, the combined biomarker model improved model fit (likelihood-ratio test p&#x2009;<&#x2009;0.001) and reclassification (NRI p&#x2009;<&#x2009;0.001), although the increase in AUC was modest. In the external validation cohort, the prespecified final Base&#x2009;+&#x2009;Combine model achieved an AUC of 0.697 (95% CI 0.581-0.813), compared with 0.672 (95% CI 0.553-0.791) for the base model. External calibration remained imperfect for both models. The base model showed a calibration intercept of -1.609, a calibration slope of 0.385, and a Brier score of 0.138, whereas the final Base&#x2009;+&#x2009;Combine model showed a calibration intercept of 3.782, a calibration slope of 0.402, and a Brier score of 0.089. In external decision-curve analysis, the base model provided greater net benefit at lower threshold probabilities, whereas the final Base&#x2009;+&#x2009;Combine model showed greater net benefit mainly within a narrower higher-threshold range (approximately 0.14-0.30). Given the limited number of external events, these findings should be interpreted as preliminary evidence of transportability rather than as definitive support for a clearly superior prediction tool. In adults with questionnaire-defined OSA from NHANES, inflammation-nutrition markers, particularly ALI, showed stronger mortality-related signal than TyG-related indices at the single-marker level, while NPAR showed supportive signal in selected analyses. More importantly, a combined inflammatory-metabolic biomarker model provided modest incremental enrichment for 5-year all-cause mortality risk benchmarking beyond routine clinical variables. In an external multicenter cohort with PSG-confirmed OSA, the final Base&#x2009;+&#x2009;Combine model showed moderate but preliminary transportability, with slightly improved discrimination but poor calibration. Any incremental net benefit in external decision-curve analysis appeared to be confined to a relatively narrow higher-threshold range. These findings support pragmatic risk benchmarking rather than immediate use as a clearly superior clinical prediction tool.

Acinetobacter baumannii is a critical-priority pathogen with increasing antibiotic resistance. Here, we define the mechanism of abaucin, a first-in-class narrow-spectrum antibiotic that selectively targets A. baumannii by inhibiting its essential lipoprotein transporter, LolDF. Extending prior studies of archived strains, we demonstrate potent activity against clinically isolated carbapenem-resistant A. baumannii (CRAB) strains both in vitro and in a murine pneumonia model. Cryo-EM structures of abaucin-bound LolDF reveal symmetric binding of two abaucin molecules within the LolDF cavity, which lock the transporter in a non-productive, outward-open conformation. Biochemical and structural analyses show that abaucin does not block substrate binding but instead traps the substrate-loaded transporter and prevents transfer to LolA. Together, these findings uncover a unique symmetry-enabled conformation-hijacking mechanism and establish LolDF as a tractable target for precision antibiotic development.

In this study, a two-stage SKB-FA-XGB feature selection method consisting of both a statistical filter (SelectKBest) and a meta-heuristic spiral (Firefly (FA)-XGBoost) is proposed to improve wind power plant (WPP) production prediction performance. This proposed method aims to improve the prediction performance and reduce the processing time of studies with large feature spaces. To achieve this goal, the feature pool is first narrowed down using SelectKBest, and then a more intelligent selection is made in the subspace using FA-XGBoost. Meteorological measurement data and WPP production data from Manisa, T&#xfc;rkiye, were used to implement this planned method. During the application phase, the meteorological data were decomposed into Ensemble Empirical Mode Decomposition (EEMD) signals, and then the most effective signal sets for prediction were determined using the proposed feature selection method. Instantaneous production forecasts were performed using the XGBoost machine learning method with the determined signal sets and WPP production data. As a result of the predictions made, the prediction accuracy increased by 25.98% compared to raw data when all EEMD signals were used. When only FA-XGBoost preprocessing was applied to the EEMD signal set, the accuracy rate increased by 25.98%, while applying only SelectKBest preprocessing resulted in an increase of 27.89%. However, applying the proposed SKB-FA-XGB hybrid method improved prediction accuracy by 28.33% compared to raw data. Furthermore, when comparing the computational cost of SelectKBest pre-signal processing and the SKB-FA-XGB method, it was found that the solution set obtained with SKB FA XGB performed calculations on average 50% faster. All these results demonstrated that the proposed SKB-FA-XGB approach performs well in terms of both efficiency and accuracy.

Quantitative histomorphometric analysis of peripheral nerves is essential for assessing axonal regeneration and remyelination, but manual analysis is labor-intensive and impractical for large-scale studies. This study compared three automated morphometric approaches with conventional manual analysis to identify an efficient and reliable alternative. Six rat sciatic nerves, including three na&#xef;ve nerves and three regenerating nerves following crush injury, were analyzed using semithin transverse sections stained with toluidine blue. Manual analysis by three independent observers served as the reference standard. Automated analyses were performed using Trainable Weka Segmentation, AxonDeepSeg, and AxonDeepSeg with manual refinement. Axon count, axon diameter, axon area, g-ratio, myelin thickness, and analysis time were compared. Manual analysis required the longest processing time (53.1&#x2009;&#xb1;&#x2009;16.5&#xa0;min for na&#xef;ve nerves and 63.4&#x2009;&#xb1;&#x2009;3.9&#x2009;min for regenerating nerves), whereas automated approaches reduced analysis time by more than half, with AxonDeepSeg being the fastest (10.2&#x2009;&#xb1;&#x2009;0.5&#xa0;min and 6.7&#x2009;&#xb1;&#x2009;0.2&#xa0;min, respectively). Agreement between automated and manual measurements was primarily evaluated using Bland-Altman analysis (mean bias and 95% limits of agreement). Fully automated methods demonstrated variable levels of agreement, with wider limits of agreement, particularly in regenerating nerves. A hybrid workflow combining deep learning-based segmentation with selective manual refinement showed reduced bias and relatively narrower limits of agreement compared with other automated approaches, while maintaining improved time efficiency.

Upper airway airflow biomechanics in children are inextricably linked to regional anatomy and physiological function. This study integrates advanced medical imaging with computational fluid dynamics (CFD) to characterize the aerodynamic properties of the pediatric upper airway via three-dimensional (3D) reconstruction. These biomechanical insights aim to clarify the pathogenesis of airway disorders and inform diagnostic and therapeutic strategies. We enrolled four healthy pediatric subjects (aged 6.8-11.9 years; two males, two females) with no history of upper respiratory pathology. DICOM datasets were imported into Mimics 21.0 to segment the air-fluid volumes (nasal cavity, nasopharynx, and pharynx) via Hounsfield unit thresholding. Subsequent 3D surface models were smoothed in Geomagic Studio 17.0 and volumetrically meshed using Ansys ICEM 21.0. Steady-state aerodynamic simulations were executed in Ansys Fluent 21.0 at a physiological flow rate of 500 mL/s. Under quiet breathing conditions, inlet flow velocities ranged from 2.122 to 9.8&#xa0;m/s (specifically 3.959, 2.122, 3.070, and 9.8&#xa0;m/s for Subjects A-D, respectively). The distances from the nasal vestibule to the choanae ranged from 5.37 to 6.38&#xa0;cm. Nasal resistance was measured at 0.1148, 0.1002, 0.109, and 0.42&#xa0;Pa/(cm3/s), respectively. Aerodynamic analyses revealed localized turbulence and pronounced pressure gradients primarily at the nasal valve, Little's area, bilateral choanae, and the epiglottis. While wall shear stress (WSS) was largely uniform throughout the airway, distinct peaks were identified at the nasal valve and Little's area. The elevated nasal resistance in Subject D correlated with localized anatomical narrowing and high inlet velocity, reflecting normal pediatric physiological variance. Pediatric upper airway aerodynamics exhibit substantial intra-regional and inter-individual heterogeneity, characterized by elevated turbulence and shear stress concentrated at the nasal valve and nasopharynx. The synergy of 3D anatomical modeling and CFD simulation establishes a robust paradigm for evaluating airway biomechanics. Clinically, these CFD-derived metrics hold significant promise for localizing functional stenoses, enhancing diagnostic precision, and facilitating personalized surgical interventions for pediatric upper airway obstruction.

Tissue culture optimization in orchids is constrained by the impracticality of experimentally testing all possible combinations of environmental and nutritional factors. In this study, the interactive effects of culture media composition, light quality, plant developmental status (rooted vs. rootless), and culture configuration (single-phase vs. two-phase) on organ-specific morpho-physiological traits of Phalaenopsis amabilis were investigated under in vitro condition. Growth variables, pigment composition, carbohydrate metabolism, and maximum quantum efficiency of photosystem II (Fv/Fm) were quantified separately in leaves and aerial roots. The primary objective was to predict trait-specific optimal treatment regions using fuzzy inference system (FIS) and adaptive neuro-fuzzy inference system (ANFIS) models trained on organ-resolved datasets derived from 60 treatment combinations across 16 traits. ANFIS exhibited superior capability compared with FIS in predicting nonlinear response surfaces and identifying trait-specific optimal regions. For leaf growth traits, ANFIS predicted optimal regions under orange-red light combined with moderate nitrogen (N) availability, whereas FIS produced narrower and more localized optima. For root biomass and carbohydrate accumulation traits, ANFIS predicted red light dominated optimal regions with elevated phosphorus (P) and reduced N, indicating stronger sensitivity of sink-related traits to light nutrient interactions. For leaf pigment accumulation traits, ANFIS identified broader optimal regions under blue light with lower N levels, while carbohydrate related traits showed distinct optima under red and green spectral conditions depending on nutrient balance. Overall, ANFIS generated more distinct and physiologically consistent response surfaces than FIS across all traits. Machine learning assisted modeling effectively identified organ-specific optimal treatment regions and revealed complex nonlinear interactions among experimental factors that are not directly observable from mean treatment comparisons. The ANFIS framework provides a robust predictive tool for optimizing orchid tissue culture systems and for generating testable hypotheses for future in vitro propagation studies.

The immunosuppressive prodrugs azathioprine and 6-mercaptopurine necessitate therapeutic drug monitoring of their active metabolite, 6-thioguanine (6-TG), due to their narrow therapeutic window and substantial risk of severe adverse effects. Conventional chromatographic techniques are accurate but impractical for point-of-care (POC) applications. Conversely, existing electrochemical sensors, despite their widespread use, suffer from an over-reliance on nanomaterial modifications to enhance analytical performance and face persistent challenges associated with calibration. This work resolves a long-standing knowledge gap by providing the first experimental validation of the 6-TG redox mechanism on a Nafion-modified screen-printed carbon electrode (SPCE). Through dithiothreitol intervention and electrochemical kinetic analysis, we confirm that 6-TG oxidation proceeds via a disulfide bond-mediated, four-electron, four-proton multi-step pathway. Critically, elucidation of this mechanism reveals a consistent kinetic framework, which directly inspires a universal-slope (US) calibration-free strategy wherein the calibration slope becomes a stable parameter, obviating frequent recalibration for POC applications. Leveraging this mechanistic insight, we constructed a smartphone-assisted electrochemical sensor on the same Nafion/SPCE platform for on-site detection of 6-TG in erythrocyte lysate and serum. The sensor exhibits a linear response from 0.1 to 15&#x202f;&#x3bc;M in erythrocyte lysate, effectively covering the clinically relevant therapeutic window, alongside excellent selectivity and reproducibility. Clinical validation using 50 patient samples demonstrates strong agreement with high-performance liquid chromatography results, and the US method yields outcomes statistically equivalent to those obtained via the standard addition approach. By resolving the redox mechanism and translating this insight into a calibration-free POC sensor, this work offers a clinically deployable solution for personalized thiopurine therapy.

The United States has one of the highest rates of sexually transmitted infections (STIs) among high-income countries, with women-particularly young Black women-bearing the greatest burden. Gendered power dynamics are a driver of women's STI risk, yet most research has focused on couple relationships, rather than the structural gender inequalities that shape power imbalances. This study investigates the extent to which the gender pay gap, a key indicator of structural sexism, is associated with women's sexual health outcomes in the US. Drawing on theories of household bargaining and gendered power dynamics, we hypothesize that wider gender pay gaps reduce women's agency in relationships and dating markets, thereby increasing their risk of STIs. We analyzed surveillance data from 2012 to 2023 on chlamydia, gonorrhea, and syphilis incidence rates among women aged 15-44. The primary exposure was the lagged state-level female-to-male earnings ratio within racial groups. We used fixed-effects linear regression models to estimate associations that adjusted for key economic and demographic covariates. A one-percentage point increase in female-to-male earnings ratio was associated with significant declines in chlamydia (-20.4 cases per 100,000) and gonorrhea (-8.2 cases per 100,000) rates. These associations were strongest among women aged 15-29 and among Black women. Results were robust across model specifications and geographic levels. Associations with syphilis were smaller and less robust. Findings suggest that the gender pay gap functions as a structural determinant of women's sexual health and that narrowing the gap may enhance women's agency in couple and dating relationships and reduce STI risk.

This paper examines how radiating surface structure can influence the properties of beam-shaping of the piezoelectric piston type underwater acoustic transducers. The study is done using a broad theoretical, numerical and experimental method. This study presents a comprehensive analysis of the far-field radiation characteristics of circular, square, hexagonal, and octagonal piston-type ultrasonic transducers for underwater applications. The models were validated with three-dimensional finite element simulations and experimental measurements using a wafer Tonpilz transducer prototype. This analysis demonstrates that piston geometry has no significant effect on radiation characteristics for small apertures whose Equivalent Circular Diameter (ECD) is less than half the wavelength. The circular piston is found to exhibit superior performance at increased apertures. Result shows that circular pistons provide superior beam uniformity, narrow main lobes, and low side-lobe levels, making them highly efficient for focused energy transmission, sonar, and underwater communication systems. Experimental validation is provided only for the circular case, while theoretical and numerical results are presented for all pistons. This control of the beam makes the circular piston the solution to accurate acoustic control. Finite element analysis and experimental measurements on a circular wafer transducer proved the validity of the theoretical models. This high level of agreement validates that the findings can directly applied to designing advanced underwater acoustic arrays.

Neonatal parenteral nutrition (PN) remains a cornerstone of care for preterm infants and for selected term infants when enteral feeding is not possible or is clearly insufficient. In day-to-day neonatal practice, decisions about when to initiate PN, how quickly to advance macronutrient delivery, which lipid emulsion to use, and how closely to monitor biochemical tolerance are guided by several major documents rather than by a single universally adopted standard. This expert narrative review compares the principal recommendations from ASPEN, NICE, and the ESPGHAN/ESPEN/ESPR/CSPEN pediatric PN guideline series, and interprets them alongside contemporary trials, systematic reviews, meta-analyses, and clinically relevant safety guidance. Across these sources, there is broad agreement on the essentials: start PN early when clearly indicated, introduce amino acids and lipids without unnecessary delay, individualize glucose delivery according to tolerance, provide vitamins and trace elements early, and monitor closely for electrolyte disturbances and catheter- or liver-related complications. The remaining areas of disagreement are narrower but important at the bedside, particularly the upper limits of amino acid provision, timing of PN in critically ill term infants, routine use of standardized versus individualized formulations, interpretation of triglyceride concentrations, and the clinical role of mixed-oil or fish-oil-containing lipid emulsions. A practical reading of the literature suggests that the most workable neonatal PN pathway borrows the operational detail of NICE, the physiologic and subgroup-specific framework of the European guidance, and the evidentiary caution emphasized by ASPEN.

Neurosurgical procedures often require patients to maintain a rotated neck position for extended periods. This sustained posture may lead to internal jugular vein (IJV) compression, particularly in individuals with an elongated styloid process (ESP). This study aimed to elucidate the dynamic changes in IJV compression among patients with an ESP using multi-position head-and-neck rotational computed tomographic venography (CTV) imaging, and to preliminarily investigate the key anatomical structures responsible for venous compression, thereby providing imaging and anatomical evidence for individualized treatment planning. Images from 42 consecutive head-and-neck rotational CTV scans of patients with an ESP performed between August 2024 and December 2025 were reviewed. The slices for measurement were selected from images obtained in four positions (extension, flexion, left rotation, and right rotation) based on the criterion of the minimum distance between the IJV and its key adjacent structures (bony, muscular, and vascular). The shortest distance between these key structures and the IJV, as well as the minimum IJV diameter and cross-sectional area at the same slice level, was measured. The presence of collateral circulation in bilateral IJVs in each position was assessed, and a preliminary analysis of the compressive structures at the site of maximal narrowing of the IJV was performed. A total of 42 patients were included in the study, of whom 30 were identified as positive for severe IJV compression or complete IJV interruption, yielding a positivity rate of 71.43%. At the carotid artery (CA) and sternocleidomastoid muscle (SCM) levels, the diameter and cross-sectional area of the ipsilateral IJV were significantly smaller during left and right neck rotation. In contrast, at the transverse process (TP) and styloid process (SP) levels, the ipsilateral IJV diameter and area were largest during left and right neck rotations. Further, among the four positions, flexion showed the shortest distance between the bilateral C1 TP and SP. During left and right neck rotation, the degree of collateral circulation around the ipsilateral IJV was significantly increased. All reported differences were statistically significant (P<0.05). A total of 240 vascular states were observed across the four positions, of which 80 (33.3%) exhibited severe stenosis or occlusion. Dual-structure compression was the predominant type, with the most common combinations being muscle-muscle compression (27/80, 33.75%), muscle-vessel compression (23/80, 28.75%), and bone-bone compression (11/80, 13.75%). In patients with an ESP, left and right neck rotation significantly increases the incidence of ipsilateral IJV compression and even occlusion, as assessed by multi-position head-and-neck rotational CTV. This finding has important clinical implications, as it may guide modifications to patients' daily habits and improve perioperative evaluation protocols.

Despite advances in human immunodeficiency virus (HIV) treatment, disparities in HIV-related mortality persist across demographic groups in the United States. The COVID-19 pandemic disrupted healthcare systems and may have influenced established mortality trends. This study evaluates HIV-related mortality in the U.S. from 1999 to 2023, with emphasis on changes following the onset of COVID-19. Data were obtained from the CDC WONDER database, identifying HIV-related deaths (ICD-10: B20-B24) among adults aged 25 to 85+. Age-adjusted mortality rates (AAMR) per 100&#xa0;000 were calculated. Trends were analyzed using Joinpoint regression to estimate annual percent changes (APCs) and average annual percent changes (AAPCs). From 1999 to 2023, there were 271&#xa0;932 HIV-related deaths in the U.S. The overall AAMR declined by an AAPC of -4.34%, with a slower post-COVID decline of -4.19% (P <&#xa0;0.05) from 2020 to 2023. Gender-stratified analysis showed greater post-COVID declines in women (APC:&#xa0;-&#xa0;.58%) than in men (APC:&#xa0;-3.90%). Older adults (85+) experienced a post-COVID increase in mortality (APC:&#xa0;+12.37%). Urban centers showed an APC increase (+2.33%), while rural areas continued to decline. Racial disparities narrowed modestly. Black and Hispanic populations saw sharper post-COVID declines (APCs:&#xa0;-6.21% and -6.26%, respectively) compared to White populations (-1.33%). The Southern U.S. remained the highest-burdened region across both timeframes. Observed mortality trends were temporally associated with demographic characteristics and urbanization patterns during the COVID-19 period. While HIV mortality continues to decline, the COVID-19 pandemic has disrupted progress, especially among elderly and urban populations. Persistent disparities demand targeted, equitable public health interventions.