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1.
J Biomed Opt ; 30(Suppl 1): S13702, 2025 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39034960

RESUMEN

Significance: Near-infrared autofluorescence (NIRAF) utilizes the natural autofluorescence of parathyroid glands (PGs) to improve their identification during thyroid surgeries, reducing the risk of inadvertent removal and subsequent complications such as hypoparathyroidism. This study evaluates NIRAF's effectiveness in real-world surgical settings, highlighting its potential to enhance surgical outcomes and patient safety. Aim: We evaluate the effectiveness of NIRAF in detecting PGs during thyroidectomy and central neck dissection and investigate autofluorescence characteristics in both fresh and paraffin-embedded tissues. Approach: We included 101 patients diagnosed with papillary thyroid cancer who underwent surgeries in 2022 and 2023. We assessed NIRAF's ability to locate PGs, confirmed via parathyroid hormone assays, and involved both junior and senior surgeons. We measured the accuracy, speed, and agreement levels of each method and analyzed autofluorescence persistence and variation over 10 years, alongside the expression of calcium-sensing receptor (CaSR) and vitamin D. Results: NIRAF demonstrated a sensitivity of 89.5% and a negative predictive value of 89.1%. However, its specificity and positive predictive value (PPV) were 61.2% and 62.3%, respectively, which are considered lower. The kappa statistic indicated moderate to substantial agreement (kappa = 0.478; P < 0.001 ). Senior surgeons achieved high specificity (86.2%) and PPV (85.3%), with substantial agreement (kappa = 0.847; P < 0.001 ). In contrast, junior surgeons displayed the lowest kappa statistic among the groups, indicating minimal agreement (kappa = 0.381; P < 0.001 ). Common errors in NIRAF included interference from brown fat and eschar. In addition, paraffin-embedded samples retained stable autofluorescence over 10 years, showing no significant correlation with CaSR and vitamin D levels. Conclusions: NIRAF is useful for PG identification in thyroid and neck surgeries, enhancing efficiency and reducing inadvertent PG removals. The stability of autofluorescence in paraffin samples suggests its long-term viability, with false positives providing insights for further improvements in NIRAF technology.


Asunto(s)
Imagen Óptica , Glándulas Paratiroides , Espectroscopía Infrarroja Corta , Tiroidectomía , Humanos , Glándulas Paratiroides/cirugía , Glándulas Paratiroides/metabolismo , Masculino , Femenino , Persona de Mediana Edad , Imagen Óptica/métodos , Adulto , Espectroscopía Infrarroja Corta/métodos , Adhesión en Parafina/métodos , Anciano , Cáncer Papilar Tiroideo/cirugía , Cáncer Papilar Tiroideo/patología , Cáncer Papilar Tiroideo/metabolismo , Receptores Sensibles al Calcio/metabolismo , Receptores Sensibles al Calcio/análisis
2.
Gigascience ; 132024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-39172544

RESUMEN

BACKGROUND: As single-cell sequencing technologies continue to advance, the growing volume and complexity of the ensuing data present new analytical challenges. Large cellular populations from single-cell atlases are more difficult to visualize and require extensive processing to identify biologically relevant subpopulations. Managing these workflows is also laborious for technical users and unintuitive for nontechnical users. RESULTS: We present TooManyCellsInteractive (TMCI), a browser-based JavaScript application for interactive exploration of cell populations. TMCI provides an intuitive interface to visualize and manipulate a radial tree representation of hierarchical cell subpopulations and allows users to easily overlay, filter, and compare biological features at multiple resolutions. Here we describe the software architecture and demonstrate how we used TMCI in a pan-cancer analysis to identify unique survival pathways among drug-tolerant persister cells. CONCLUSIONS: TMCI will facilitate exploration and visualization of large-scale sequencing data in a user-friendly way. TMCI is freely available at https://github.com/schwartzlab-methods/too-many-cells-interactive. An example tree from data within this article is available at https://tmci.schwartzlab.ca/.


Asunto(s)
Análisis de la Célula Individual , Programas Informáticos , Análisis de la Célula Individual/métodos , Humanos , Biología Computacional/métodos , Neoplasias/genética , Neoplasias/patología
3.
Neurology ; 103(6): e209814, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39173104

RESUMEN

BACKGROUND AND OBJECTIVES: Acute ischemic stroke patients with a large vessel occlusion (LVO) who present to a primary stroke center (PSC) often require transfer to a comprehensive stroke center (CSC) for thrombectomy. Not much is known about specific characteristics at the PSC that are associated with infarct growth during transfer. Gaining more insight into these features could aid future trials with cytoprotective agents targeted at slowing infarct growth. We aimed to identify baseline clinical and imaging characteristics that are associated with fast infarct growth rate (IGR) during interhospital transfer. METHODS: We included patients from the CT Perfusion to Predict Response to Recanalization in Ischemic Stroke Project, a prospective multicenter study. Patients with an anterior circulation LVO who were transferred from a PSC to a CSC for consideration of thrombectomy were eligible if imaging criteria were fulfilled. A CT perfusion (CTP) needed to be obtained at the PSC followed by an MRI at the CSC, before consideration of thrombectomy. The interhospital IGR was defined as the difference between the infarct volumes on MRI and CTP, divided by the time between the scans. Multivariable logistic regression was used to determine characteristics associated with fast IGR (≥5 mL/h). RESULTS: A total of 183 patients with a median age of 74 years (interquartile range 61-82), of whom 99 (54%) were male and 82 (45%) were fast progressors, were included. At baseline, fast progressors had a higher NIH Stroke Scale score (median 16 vs 13), lower cerebral blood volume index (median 0.80 vs 0.89), more commonly poor collaterals on CT angiography (35% vs 13%), higher hypoperfusion intensity ratios (HIRs) (median 0.51 vs 0.34), and larger core volumes (median 11.80 mL vs 0.00 mL). In multivariable analysis, higher HIR (adjusted odds ratio [aOR] for every 0.10 increase 1.32 [95% CI 1.10-1.59]) and larger core volume (aOR for every 10 mL increase 1.54 [95% CI 1.20-2.11]) remained independently associated with fast IGR. DISCUSSION: Fast infarct growth during interhospital transfer of acute stroke patients is associated with imaging markers of poor collaterals on baseline imaging. These markers are promising targets for patient selection in cytoprotective trials aimed at reducing interhospital infarct growth.


Asunto(s)
Accidente Cerebrovascular Isquémico , Transferencia de Pacientes , Trombectomía , Humanos , Masculino , Anciano , Femenino , Estudios Prospectivos , Trombectomía/métodos , Accidente Cerebrovascular Isquémico/diagnóstico por imagen , Accidente Cerebrovascular Isquémico/cirugía , Persona de Mediana Edad , Anciano de 80 o más Años , Imagen por Resonancia Magnética , Tomografía Computarizada por Rayos X
4.
Artículo en Inglés | MEDLINE | ID: mdl-39163097

RESUMEN

The versatility of metal-organic frameworks (MOFs) has led to groundbreaking applications in a wide variety of fields, especially in the areas of energy, environment, and sustainability. For example, MOFs can be designed for high uptake of toxic gases and pollutants, such as CO2, NH3, and SO2, but designing a single MOF that shows tangible uptake for all of these gases is challenging due to the differences in the chemical and physical properties of these molecules. To this end, integrating multiple MOFs onto textile fibers and crafting various structures have emerged as pivotal developments, enhancing framework durability and usability. MOF composites prepared on readily available textile fibers offer the flexibility essential for critical applications, including heterogeneous catalysis, chemical sensing, toxic gas adsorption, and drug delivery, while preserving the unique characteristics of MOFs. This study introduces a scalable and adaptable method for seamlessly embedding multiple high-performing MOFs onto a single textile fiber using a dip-coating method. We explored the uptake capacity of these multi-MOF composites for CO2, NH3, and SO2 and observed a performance similar to that of traditional powdered materials. Along with harmful gas adsorption, we also have evaluated the permeation and reactivity of these MOF/textile composites toward chemical warfare agents (CWAs) like GD (soman), HD (mustard gas), and VX. In combination, these results demonstrate a fundamental advancement toward establishing a consistent strategy for the hydrolysis of nerve agents in real-world scenarios. This approach can substantially increase the protection toward CWAs and enhance the effectiveness of protective equipment such as fabrics for protective garments. This dip-coating method for the integration of multiple MOFs on a single textile fiber unlocks a wealth of possibilities and paves the way for future innovations in the deployment of MOF-based composites.

6.
Lancet Neurol ; 23(9): 938-950, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39152029

RESUMEN

Intracranial pressure monitoring enables the detection and treatment of intracranial hypertension, a potentially lethal insult after traumatic brain injury. Despite its widespread use, robust evidence supporting intracranial pressure monitoring and treatment remains sparse. International studies have shown large variations between centres regarding the indications for intracranial pressure monitoring and treatment of intracranial hypertension. Experts have reviewed these two aspects and, by consensus, provided practical approaches for monitoring and treatment. Advances have occurred in methods for non-invasive estimation of intracranial pressure although, for now, a reliable way to non-invasively and continuously measure intracranial pressure remains aspirational. Analysis of the intracranial pressure signal can provide information on brain compliance (ie, the ability of the cranium to tolerate volume changes) and on cerebral autoregulation (ie, the ability of cerebral blood vessels to react to changes in blood pressure). The information derived from the intracranial pressure signal might allow for more individualised patient management. Machine learning and artificial intelligence approaches are being increasingly applied to intracranial pressure monitoring, but many obstacles need to be overcome before their use in clinical practice could be attempted. Robust clinical trials are needed to support indications for intracranial pressure monitoring and treatment. Progress in non-invasive assessment of intracranial pressure and in signal analysis (for targeted treatment) will also be crucial.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Hipertensión Intracraneal , Presión Intracraneal , Humanos , Lesiones Traumáticas del Encéfalo/fisiopatología , Lesiones Traumáticas del Encéfalo/diagnóstico , Lesiones Traumáticas del Encéfalo/terapia , Presión Intracraneal/fisiología , Hipertensión Intracraneal/diagnóstico , Hipertensión Intracraneal/fisiopatología , Hipertensión Intracraneal/etiología , Monitoreo Fisiológico/métodos , Adulto , Monitorización Neurofisiológica/métodos
7.
J Phys Ther Educ ; 38(3): 231-238, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39150258

RESUMEN

INTRODUCTION: The definition of excellence in physical therapy (PT) education is evolving, yet the role of postprofessional residency education remains uncertain. Arguments in favor of required residency have emerged through the re-visioning of PT education across the continuum. Yet, little evidence exists whether residency education further develops clinical skills, clinical knowledge, and clinical reasoning abilities. REVIEW OF LITERATURE: Previous studies have explored the development of the novice physical therapist in the first 2 years of practice; however, there is little evidence about the outcomes of PT residency education. Thus, this study looked to explore the development of learners through their residency education and to identify the critical elements of the teaching and learning environment in residency education. SUBJECTS: Eleven PT residency programs and 13 residents participated in a qualitative study to explore the learner development through residency. Each residency program consisted of a residency program director, one or more mentors identified by the residency program director, and at least one physical therapist resident. Semistructured interviews were conducted with program participants, and journal entries were collected from residents. METHODS: Using a purposeful sample of convenience, an exploratory, multiple-site/specialty area qualitative case study design was conducted. RESULTS: Three emerging themes were identified including growth of self, becoming a member of the community of practice, and facilitation of learning through mentoring. Through the transformative journey of residency education, there are critical elements of the learning environment supporting deep learning within the community of practice. These elements include the provision of opportunities and adequate time and space for learning to occur. DISCUSSION AND CONCLUSION: The intentional design of the community of practice through residency education facilitates the development of the novice clinician to experienced clinician in an accelerated period of time. In addition, residency graduates develop characteristics similar to adaptive learners through planned teaching and learning opportunities. Finally, the structure of residency education mattered to the resident participants such that the learning environment enhanced peer learning and the development of professional relationships.


Asunto(s)
Competencia Clínica , Internado y Residencia , Investigación Cualitativa , Humanos , Fisioterapeutas/educación , Femenino , Masculino , Especialidad de Fisioterapia/educación , Mentores/educación , Entrevistas como Asunto
8.
Head Neck ; 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39104194

RESUMEN

BACKGROUND: Hypocalcemia is the most common postoperative complication of total thyroidectomy. Near-infrared autofluorescence (NIRAF) technology is a surgical adjunct that has been increasingly utilized with the aim of preventing postoperative hypocalcemia, but its clinical benefits have not yet been firmly established. The aim of this study was to assess the clinical benefit of utilizing NIRAF technology in patients undergoing total thyroidectomy. METHODS: A systematic review and meta-analysis of randomized clinical trials was performed according to PRISMA guidelines. RESULTS: Seven randomized clinical trials with 1437 patients (318 males, 22.13%) undergoing total thyroidectomy were included for analysis. Risk of postoperative hypocalcemia was reduced in the NIRAF arm (RR, 0.65; 95%CI, 0.50-0.84). Use of NIRAF was also associated with a reduction in the risk of permanent parathyroid dysfunction (RR, 0.46; 95%CI, 0.22-0.95) and inadvertent parathyroid gland resection (RR, 0.40; 95%CI, 0.26-0.60). CONCLUSIONS: We present a systematic review and meta-analysis of randomized clinical trials examining the impact of NIRAF technology on preservation of parathyroid function. Our results suggest that use of camera-based NIRAF technology reduces the risk of postoperative hypocalcemia, permanent parathyroid dysfunction, and inadvertent parathyroid gland resection.

9.
Health Sci Rep ; 7(8): e2307, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39139465

RESUMEN

Background and Aims: The purpose of this study was to compare the knowledge and practices of specialist and experienced nonspecialist physical therapists in performing patient education about physical activity with patients with heart failure (HF). Methods: Responses on a nationwide anonymous online survey were used to compare specialist and experienced nonspecialist physical therapists on knowledge and frequency of providing physical activity related education to patients hospitalized with acutely decompensated HF. Responses to survey items were scored on 5-point scales ranging from "Strongly agree" to "Strongly disagree" or "Always" to "Never." Mann-Whitney U statistics were used to compare specialist and experienced nonspecialist responses and Wilcoxon signed-ranks tests were used to examine the gap between knowledge and practice. Results: Twenty-seven specialists and 43 experienced nonspecialists completed the survey. Both groups were similar in age, and experience treating patients hospitalized with acutely decompensated HF. Both groups "strongly agree" that they had the required knowledge and skills to educate patients with HF on the physical activity topics. However, specialists more often than experienced nonspecialists provided education on topics such as how to monitor vital signs during physical activity ("most of the time" vs. "about half of the time") that promoted patient confidence and safety during exercise. Specialists demonstrated a smaller gap between knowledge and frequency of providing patient education than experienced nonspecialists on three of the four patient education topics. Conclusion: Specialist physical therapists treating patients with HF in the inpatient hospital setting provided patient education on physical activity at a level more closely matching their skills and the clinical practice guideline than did experienced nonspecialists. Physical therapy clinical specialists practicing in the inpatient hospital setting may improve patient outcomes and lower costs to the health care system by improving physical activity adherence and thereby may reduce avoidable hospital readmissions.

11.
Blood Adv ; 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39093952

RESUMEN

The effect of prior inotuzumab ozogamicin (InO) treatment on brexucabtagene autoleucel (brexu-cel) outcomes remains unclear in adults with acute lymphoblastic leukemia (ALL), particularly the influence off previous InO response and the timing of administration. We conducted a retrospective multicenter analysis of 189 patients with relapsed/refractory (r/r) ALL treated with brexu-cel. Over half of the patients received InO before brexu-cel (InO-exposed). InO-exposed patients were more heavily pretreated (p= 0.02) and frequently had active marrow disease pre-apheresis (p= 0.03). Response rate and toxicity profile following brexu-cel were comparable for InO-exposed and InO-naïve; however, consolidation therapy post brexu-cel response was utilized at a higher rate in InO-naïve patients (p= 0.005). With a median follow up of 11.4 months, InO-exposed patients had inferior progression-free survival (PFS) (p=0.013) and overall survival (OS) (p=0.006) in univariate analyses; however, prior InO exposure did not influence PFS (HR 1.20, 95%CI, 0.71-2.03) in multivariate models. When InO-exposed patients were stratified according to prior InO response, InO responders had superior PFS (p=0.002) and OS (p<0.0001) relative to InO-refractory. The timing of administering InO did not affect brexu-cel outcomes, with comparable PFS (p=0.51) and OS (p=0.86) for patients receiving InO as bridging therapy or pre-apheresis. In conclusion, while InO exposure was associated with inferior survival outcomes following brexu-cel in unadjusted analyses, these associations were no longer significant in multivariate analyses, suggesting it is unlikely that InO negatively impacts brexu-cel efficacy. Our data instead imply that InO-exposed recipients of brexu-cel tend to be higher-risk patients with intrinsic adverse leukemia biology.

13.
Endocr Pathol ; 2024 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-39096324

RESUMEN

RAS p.Q61R is the most prevalent hot-spot mutation in RAS and RAS-like mutated thyroid nodules. A few studies evaluated RAS p.Q61R by immunohistochemistry (RASQ61R-IHC). We performed a retrospective study of an institutional cohort of 150 patients with 217 thyroid lesions tested for RASQ61R-IHC, including clinical, cytologic and molecular data. RASQ61R-IHC was performed on 217 nodules (18% positive, 80% negative, and 2% equivocal). RAS p.Q61R was identified in 76% (n = 42), followed by RAS p.Q61K (15%; n = 8), and RAS p.G13R (5%; n = 3). NRAS p.Q61R isoform was the most common (44%; n = 15), followed by NRAS p.Q61K (17%; n = 6), KRAS p.Q61R (12%; n = 4), HRAS p.Q61R (12%; n = 4), HRAS p.Q61K (6%; n = 2), HRAS p.G13R (6%; n = 2), and NRAS p.G13R (3%; n = 1). RASQ61R-IHC was positive in 47% of noninvasive follicular thyroid neoplasms with papillary-like nuclear features (NIFTP; 17/36), 22% of follicular thyroid carcinomas (FTC; 5/23), 10% of follicular thyroid adenomas (FTA; 4/40), and 8% of papillary thyroid carcinomas (PTC; 9/112). Of PTC studied (n = 112), invasive encapsulated follicular variant (IEFVPTC; n = 16) was the only subtype with positive RASQ61R-IHC (56%; 9/16). Overall, 31% of RAS-mutated nodules were carcinomas (17/54); and of the carcinomas, 94% (16/17) were low-risk per American Thyroid Associated (ATA) criteria, with only a single case (6%; 1/17) considered ATA high-risk. No RAS-mutated tumors recurred, and none showed local or distant metastasis (with a follow-up of 0-10 months). We found that most RAS-mutated tumors are low-grade neoplasms. RASQ61R-IHC is a quick, cost-effective, and reliable way to detect RAS p.Q61R in follicular-patterned thyroid neoplasia and, when malignant, guide surveillance.

14.
J Otolaryngol Head Neck Surg ; 53: 19160216241265684, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39092609

RESUMEN

BACKGROUND: The aim of this study is to describe the management and associated follow-up strategies adopted by thyroid surgeons with different surgical volumes when loss of signal (LOS) occurred on the first side of planned bilateral thyroid surgery, and to further define the consensus on intraoperative neuromonitoring (IONM) applications. METHODS: The International Neural Monitoring Study Group (INMSG) web-based survey was sent to 950 thyroid surgeons worldwide. The survey included information on the participants, IONM team/equipment/procedure, intraoperative/postoperative management of LOS, and management of LOS on the first side of thyroidectomy for benign and malignant disease. RESULTS: Out of 950, 318 (33.5%) respondents completed the survey. Subgroup analyses were performed based on thyroid surgery volume: <50 cases/year (n = 108, 34%); 50 to 100 cases/year (n = 69, 22%); and >100 cases/year (n = 141, 44.3%). High-volume surgeons were significantly (P < .05) more likely to perform the standard procedures (L1-V1-R1-S1-S2-R2-V2-L2), to differentiate true/false LOS, and to verify the LOS lesion/injury type. When LOS occurs, most surgeons arrange otolaryngologists or speech consultation. When first-side LOS occurs, not all respondents decided to perform stage contralateral surgery, especially for malignant patients with severe disease (eg, extrathyroid invasion and poorly differentiated thyroid cancer). CONCLUSIONS: Respondents felt that IONM was optimized when conducted under a collaborative team-based approach, and completed IONM standard procedures and management algorithm for LOS, especially those with high volume. In cases of first-site LOS, surgeons can determine the optimal management of disease-related, patient-related, and surgical factors. Surgeons need additional education on LOS management standards and guidelines to master their decision-making process involving the application of IONM.


Asunto(s)
Tiroidectomía , Humanos , Tiroidectomía/métodos , Encuestas y Cuestionarios , Monitorización Neurofisiológica Intraoperatoria , Enfermedades de la Tiroides/cirugía , Pautas de la Práctica en Medicina/estadística & datos numéricos , Traumatismos del Nervio Laríngeo Recurrente/prevención & control , Traumatismos del Nervio Laríngeo Recurrente/etiología , Parálisis de los Pliegues Vocales/etiología , Femenino , Masculino
15.
J Acoust Soc Am ; 156(1): 65-80, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38949286

RESUMEN

Environment estimation is a challenging task in reverberant settings such as the underwater and indoor acoustic domains. The locations of reflective boundaries, for example, can be estimated using acoustic echoes and leveraged for subsequent, more accurate localization and mapping. Current boundary estimation methods are constrained to high signal-to-noise ratios or are customized to specific environments. Existing methods also often require a correct assignment of echoes to boundaries, which is difficult if spurious echoes are detected. To evade these limitations, a convolutional neural network (NN) method is developed for robust two-dimensional boundary estimation, given known emitter and receiver locations. A Hough transform-inspired algorithm is leveraged to transform echo times of arrival into images, which are amenable to multi-resolution regression by NNs. The same architecture is trained on transform images of different resolutions to obtain diverse NNs, deployed sequentially for increasingly refined boundary estimation. A correct echo labeling solution is not required, and the method is robust to reverberation. The proposed method is tested in simulation and for real data from a water tank, where it outperforms state-of-the-art alternatives. These results are encouraging for the future development of data-driven three-dimensional environment estimation with high practical value in underwater acoustic detection and tracking.

16.
Artículo en Inglés | MEDLINE | ID: mdl-39018388

RESUMEN

IMPORTANCE: Although access to urogynecologic care is known to influence patient outcomes, less is known regarding geographic access to care and how it may vary by population characteristics. OBJECTIVE: The primary objective of this study was to estimate geographic accessibility of urogynecologic services in terms of drive time and by population demographics. STUDY DESIGN: We performed a descriptive study using practice location data by zip code for all board-certified urogynecologists who are American Urogynecologic Society members (n = 497) and pelvic floor physical therapists (n = 985). Drive times from each zip code to the nearest health care professional zip code were calculated. These data were then overlaid onto a map of the continental United States. Race/ethnicity, age, education, poverty status, disability status, health insurance coverage, and rurality were compared across travel times. RESULTS: Of the 31,754 zip codes of the continental United States, 389 (1.23%) had at least 1 urogynecologist, and 785 (2.47%) had at least 1 pelvic floor physical therapist; 92.29 million women older than 35 years were represented in the demographic analyses. Seventy-nine percent of the studied population live within 1 hour of a urogynecologist, and 85% live within 1 hour of a pelvic floor physical therapist. Seven percent and 3% live >2 hours from urogynecologic services, respectively. Values for drive times to all health care professionals indicate that American Indian/Alaska Native individuals have a much greater travel burden than other racial/ethnic groups. CONCLUSIONS: There are population groups with limited geographic access to urogynecologic services. Pelvic floor physical therapists are more geographically accessible to the population studied than urogynecologists.

17.
Anim Biotelemetry ; 12(1): 18, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39022453

RESUMEN

The study of animal movement provides insights into underlying ecological processes and informs analyses of behaviour and resource use, which have implications for species management and conservation. The tools used to study animal movement have evolved over the past decades, allowing for data collection from a variety of species, including those living in remote environments. Satellite-linked radio and GPS collars have been used to study polar bear (Ursus maritimus) ecology and movements throughout the circumpolar Arctic for over 50 years. However, due to morphology and growth constraints, only adult female polar bears can be reliably collared. Collars have proven to be safe, but there has been opposition to their use, resulting in a deficiency in data across much of the species' range. To bolster knowledge of movement characteristics and behaviours for polar bears other than adult females, while also providing an alternative to collars, we tested the use of fur- and ear-mounted telemetry tags that can be affixed to polar bears of any sex and age. We tested three fur tag designs (SeaTrkr, tribrush and pentagon tags), which we affixed to 15 adult and 1 subadult male polar bears along the coast of Hudson Bay during August-September 2021-2022. Fur tags were compared with ear tags deployed on 42 subadult and adult male polar bears captured on the coast or the sea ice between 2016 and 2022. We used data from the tags to quantify the amount of time subadult and adult males spent resting versus traveling while on land. Our results show the three fur tag designs remained functional for shorter mean durations (SeaTrkr = 58 days; tribrush = 47 days; pentagon = 22 days) than ear tags (121 days), but positional error estimates were comparable among the Argos-equipped tags. The GPS/Iridium-equipped SeaTrkr fur tags provided higher resolution and more frequent location data. Combined, the tags provided sufficient data to model different behavioural states. Furthermore, as hypothesized, subadult and adult male polar bears spent the majority of their time resting while on land, increasing time spent traveling as temperatures cooled. Fur tags show promise as a short-term means of collecting movement data from free-ranging polar bears. Supplementary Information: The online version contains supplementary material available at 10.1186/s40317-024-00373-2.

18.
Cureus ; 16(6): e61677, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38966434

RESUMEN

Unicornuate uterus with rudimentary horn is a rare structural uterine anomaly resulting from incomplete Mullerian duct development and/or fusion. Pregnancy in rudimentary horn is an uncommon presentation of a Mullerian anomaly and may lead to substantial morbidity and mortality due to high risk of uterine rupture with intraabdominal hemorrhage. Medical and/or surgical management may be undertaken; however, currently, no treatment guidelines exist. We describe the management of a 12-week rudimentary horn pregnancy in a 25-year-old multiparous patient with a prior spontaneous preterm breech vaginal delivery and one spontaneous early term cephalic vaginal delivery in whom this congenital uterine condition was previously unknown. The rudimentary horn, nonviable pregnancy, and contiguous ipsilateral fallopian tube were excised laparoscopically without complication. Given the infrequency of rudimentary horn pregnancies and the high risk for obstetric complications, a high index of suspicion should be maintained. We emphasize that a history of preterm birth or malpresentation should raise suspicion for maternal Mullerian anomaly, and that a minimally invasive approach can be feasible for treatment of a rudimentary horn pregnancy.

20.
Sci Adv ; 10(28): eade4454, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38985861

RESUMEN

The laser system is the most complex component of a light-pulse atom interferometer (LPAI), controlling frequencies and intensities of multiple laser beams to configure quantum gravity and inertial sensors. Its main functions include cold-atom generation, state preparation, state-selective detection, and generating a coherent two-photon process for the light-pulse sequence. To achieve substantial miniaturization and ruggedization, we integrate key laser system functions onto a photonic integrated circuit. Our study focuses on a high-performance silicon photonic suppressed-carrier single-sideband (SC-SSB) modulator at 1560 nanometers, capable of dynamic frequency shifting within the LPAI. By independently controlling radio frequency (RF) channels, we achieve 30-decibel carrier suppression and unprecedented 47.8-decibel sideband suppression at peak conversion efficiency of -6.846 decibels (20.7%). We investigate imbalances in both amplitudes and phases between the RF signals. Using this modulator, we demonstrate cold-atom generation, state-selective detection, and atom interferometer fringes to estimate gravitational acceleration, g ≈ 9.77 ± 0.01 meters per second squared, in a rubidium (87Rb) atom system.

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