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1.
Q J Exp Psychol (Hove) ; : 17470218241285884, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39268671

RESUMEN

In four experiments, we describe the first finding of a Metrical Hebb Effect. Participants are shown to exhibit a Hebb Repetition Effect for repeating, list-wide stress patterns across sequences of familiar words, even though the lexical items within the "repeating" lists do not themselves repeat. Experiment 1 established the presence of a Hebb effect for metrical patterns, demonstrating significant learning of list-wide metrical patterns over successive presentations. Experiment 2 investigated the effect's longevity, showing persistence of learned metrical information after a spacing of three non-repeating lists. Experiment 3 revealed that the effect did not persist over a longer spacing, of eight intervening lists. Experiment 4 investigated the learning mechanism, suggesting that chunking, rather than item-position binding, might account for the observed learning of metrical patterns. The authors propose that metrical-pattern learning represents a process of gradual integration of sequences of weak and strong stress accents, into higher-level units representing the stress patterns within, and across, words. We briefly discuss some implications of the Metrical Hebb Effect for phonological word-form learning, and for speech perception and production.

2.
Res Pract Thromb Haemost ; 8(6): 102556, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39309233

RESUMEN

Background: Our prior genome-wide association study of thrombin-induced platelet aggregation identified a G protein-coupled receptor kinase 5 (GRK5) noncoding variant (rs10886430-G) that is strongly associated with increased platelet reactivity to thrombin. This variant predisposes to increased risk of stroke, pulmonary embolism, and venous thromboembolism. Objectives: To determine role of platelet specific GRK5 in platelet responses to agonists and injury. Methods: Platelets from GRK5 mutant mice have been shown to have increased thrombin sensitivity, indicating that GRK5 may be a negative regulator of platelet activation. However, this has not been studied in a platelet-specific manner. We therefore used platelet-specific GRK5 mutant mice and models of thrombosis and pulmonary embolism. Results: We now demonstrate that mice lacking GRK5 specifically in platelets had a mild increase in thrombin responses in vitro and a shortened time to arterial thrombosis in vivo. In addition, platelet GRK5 mutant mice had increased thrombin but not collagen-induced thrombus burden in a mouse model of pulmonary embolism. Conclusion: These data indicate that platelet GRK5 has a significant role in limiting platelet responses to thrombin.

3.
Ergonomics ; : 1-17, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39210587

RESUMEN

Friction from knitted clothing can cause discomfort and skin issues, underscoring the importance of tactile comfort for wearers. Seamless knitted garments are assumed to be comfortable to wear, yet there is little understanding of their tactile comfort in comparison to linked seams - the most common form of knitted garment. This novel study examines the influence of a garments knitted structural architecture on clothing comfort and wearability by investigating skin friction and tactile perception across ten body regions in both male and female participants, using two commonly utilised materials and seam designs: cotton and merino wool with plain and linked seams. The impact of seam design and regional factors on skin friction and tactile perception was analysed, revealing varying levels across tested body regions. Removing seams exposed a greater surface area to skin contact, leading to higher perceived friction levels. As such, structural elements in knitted garments enhance wearer comfort.


Seamless knitwear manufacturing offers a more environmentally conscious option compared to traditional cut-and-sew processes. This study investigated the impact of knitted garment material and structure on wearer comfort by analysing skin friction and tactile perception across ten upper body regions. Removing seams increased garment-to-skin contact leading to wearer discomfort.

4.
J Am Heart Assoc ; 13(15): e034079, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39056328

RESUMEN

BACKGROUND: Although related, the precise mechanisms linking obstructive sleep apnea (OSA) and cardiovascular disease (CVD) are unclear. Platelets are mediators of CVD risk and thrombosis and prior studies suggested associations of OSA and platelet activity. The aim of this study is to assess the link between OSA, platelet activity, and CVD-related risk factors. METHODS AND RESULTS: We studied the association of OSA-measures and platelet aggregation in participants dually enrolled in the SHHS (Sleep Heart and Health Study) and FHS (Framingham Heart Study). We applied linear regression models with adjustment for demographic and clinical covariates and explored interactions with OSA and CVD-related factors, including age, sex, body mass index, hypertension, OSA diagnosis (apnea-hypopnea index 4%≥5), and aspirin use. Our final sample was of 482 participants (60 years [14.00], 50.4% female). No associations were observed between apnea-hypopnea index 4% and platelet aggregation in the main sample. Stratified analysis revealed an association in aspirin users (n=65) for our primary exposure (apnea-hypopnea index 4%, ß=0.523; P<0.001; n=65), and secondary exposures: hypoxic burden (ß=0.358; P<0.001), minimum saturation (ß=-0.519; P=0.026), and oxygen desaturation index 3% (ß=74.672; P=0.002). No associations were detected in nonaspirin users (n=417). CONCLUSIONS: No associations were detected between OSA and platelet aggregation in a community sample. Our finding that OSA associates with increased platelet aggregation in the aspirin group, most of whom use it for primary prevention of CVD, suggests that platelet aggregation may mediate the adverse impact of OSA on vascular health in individuals with existing CVD risk, supporting further investigation.


Asunto(s)
Enfermedades Cardiovasculares , Factores de Riesgo de Enfermedad Cardiaca , Agregación Plaquetaria , Apnea Obstructiva del Sueño , Humanos , Femenino , Apnea Obstructiva del Sueño/sangre , Apnea Obstructiva del Sueño/epidemiología , Apnea Obstructiva del Sueño/diagnóstico , Apnea Obstructiva del Sueño/complicaciones , Masculino , Persona de Mediana Edad , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/diagnóstico , Agregación Plaquetaria/efectos de los fármacos , Anciano , Medición de Riesgo , Aspirina/uso terapéutico , Inhibidores de Agregación Plaquetaria/uso terapéutico , Factores de Riesgo
5.
Mil Med ; 2024 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-39002107

RESUMEN

INTRODUCTION: The Special Warfare Training Wing and Special Warfare Human Performance Support Group (HPSG; all-co-authors) were established in fiscal year (FY) 2019 to consolidate and oversee all Air Force Special Warfare (AFSPECWAR) training and provide embedded medical and human performance support to candidates with the goal of improving graduation rates and the longevity of the AFSPECWAR operator. The purpose of this manuscript is to assess the impact of the HPSG on AFSPECWAR graduation rates, musculoskeletal injury (MSKI) incidence, and cost. MATERIALS AND METHODS: Graduation rates, MSKI incidence (including incidence density and cumulative incidence probability), and MSKI-related health care costs were assessed across all AFSPECWAR training pipelines spanning 8 FYs 2015-22, including Indoctrination, Assessment, and Selection Courses (Selection); Tactical Air Control Party (TACP); Special Tactics (ST), and Guardian Angel (GA). RESULTS: A total of 5,728 distinct candidates were assessed over the time frame. There were significant decreases in attrition when comparing the HPSG era (FY 19-22) with the prior 4-year period for the ST (47% vs. 82% graduates) and TACP (34% vs. 41% graduates) training pipelines. The corresponding Selection (36% graduates) and GA (80% graduates) pipeline attrition rates remained stable. MSKI incidence rates (both incidence density and cumulative incidence probability) overall were not significantly different when comparing the pre-HPSG and HPSG time frames; however, they varied between the two time frames by course. GA candidates had a decrease in MSKI during the apprentice course in the HPSG era compared with the pre-HPSG era (2.4-1.0 cases per 100 trainee weeks; P < .001), which corresponds to a nearly 20% reduction in the cumulative incidence probability (i.e., proportion of trainees injured) after 10 weeks of course. For ST and TACP courses, however, significantly increased incidence of MSKI was observed when comparing the two time frames (P < .001), while for Selection courses, the rates remained stable. A significant reduction in the cost of MSKI-related management (62% total relative value units, 83% total costs) was observed. CONCLUSION: The impact of the HPSG on attrition, MSKI incidence, and cost-of-care was not consistent across all training pipelines; however, taken together, there were no increases in attrition, and the cost of MSKI management was significantly lower.

6.
J Athl Train ; 59(7): 683-695, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-39048118

RESUMEN

Thoracic outlet syndrome (TOS) involves inconsistent symptoms, presenting a challenge for medical providers to diagnose and treat. Thoracic outlet syndrome is defined as a compression injury to the brachial plexus, subclavian artery or vein, or axillary artery or vein occurring between the cervical spine and upper extremity. Three common subcategories are now used for clinical diagnosis: neurogenic, arterial, and venous. Postural position and repetitive motions such as throwing, weightlifting, and manual labor can lead to symptoms. Generally, TOS is considered a diagnosis of exclusion for athletes due to the poor accuracy of clinical testing, including sensitivity and specificity. Thus, determining a definitive diagnosis and reporting injury is difficult. Current literature suggests there is not a gold standard diagnostic test. Rehabilitation has been shown to be a vital component in the recovery process for neurogenic TOS and for arterial TOS and venous TOS in postoperative situations.


Asunto(s)
Síndrome del Desfiladero Torácico , Síndrome del Desfiladero Torácico/diagnóstico , Síndrome del Desfiladero Torácico/rehabilitación , Humanos
7.
Int J Behav Nutr Phys Act ; 21(1): 79, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39039543

RESUMEN

BACKGROUND: Early childhood educators play a critical role in promoting physical activity and reducing sedentary time in childcare centres. However, early childhood educators receive limited specialised pre- and in-service learning opportunities relating to these behaviours and may lack the capacity to effectively engage children in healthy movement behaviours. This study aimed to examine the efficacy of an e-Learning course on increasing early childhood educators' physical activity and sedentary behaviour-related capacities. METHODS: A two-group parallel randomized controlled trial was conducted with early childhood educators in Canada (Mage = 41.78, 97% female). Participants randomized to the intervention group were asked to complete a physical activity and sedentary behaviour e-Learning course within a 4-week period. Participants randomized to the waitlist control condition were assigned to a waitlist to receive the intervention after the testing period. Participants reported on their self-efficacy, knowledge, intentions, and perceived behavioural control relating to physical activity and sedentary behaviours at baseline, post-intervention, and 3 months follow-up. Linear mixed effects models were estimated to determine difference in changes in outcomes from baseline to post-intervention, and follow-up. RESULTS: A total of 209 early childhood educators participated in the study (intervention n = 98; control n = 111). The TEACH e-Learning course was found to be efficacious at improving all of the examined outcomes, with standardized effect sizes ranging from d = 0.58 to d = 0.65 for self-efficacy outcomes, d = 0.66 to d = 1.20 for knowledge outcomes, d = 0.50 to d = 0.65 for intention outcomes, and d = 0.33 to d = 0.69 for perceived behavioural control outcomes post-intervention. The intervention effects were sustained at follow-up for all outcomes apart from perceived behavioural control to limit screen time. Additionally, the magnitude of the effect for knowledge outcomes decreased at follow-up, with standardized effect sizes ranging from d = 0.49 to d = 0.67. CONCLUSIONS: The e-Learning course was highly successful at improving early childhood educators' capacity pertaining to physical activity and sedentary behaviours. Providing training content through e-Learning may be an efficacious approach to providing continual professional learning opportunities relating to physical activity and sedentary time to early childhood educators on a large scale.


Asunto(s)
Ejercicio Físico , Conocimientos, Actitudes y Práctica en Salud , Intención , Conducta Sedentaria , Autoeficacia , Humanos , Femenino , Masculino , Adulto , Canadá , Preescolar , Promoción de la Salud/métodos , Conductas Relacionadas con la Salud
8.
J Thromb Haemost ; 22(10): 2922-2934, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38969303

RESUMEN

Genome-wide platelet transcriptomics is increasingly used to uncover new aspects of platelet biology and as a diagnostic and prognostic tool. Nevertheless, platelet isolation methods for transcriptomic studies are not standardized, introducing challenges for cross-study comparisons, data integration, and replication. In this prospective multicenter study, called "Standardizing Platelet Transcriptomics for Discovery, Diagnostics, and Therapeutics in the Thrombosis and Hemostasis Community (STRIDE)" by the International Society on Thrombosis and Haemostasis Scientific and Standardization Committees, we assessed how 3 of the most commonly used platelet isolation protocols influence metrics from next-generation bulk RNA sequencing and functional assays. Compared with washing alone, more stringent removal of leukocytes by anti-CD45 beads or PALL filters resulted in a sufficient quantity of RNA for next-generation sequencing and similar quality of RNA sequencing metrics. Importantly, stringent removal of leukocytes resulted in the lower relative expression of known leukocyte-specific genes and the higher relative expression of known platelet-specific genes. The results were consistent across enrolling sites, suggesting that the techniques are transferrable and reproducible. Moreover, all 3 isolation techniques did not influence basal platelet reactivity, but agonist-induced integrin αIIbß3 activation is reduced by anti-CD45 bead isolation compared with washing alone. In conclusion, the isolation technique chosen influences genome-wide transcriptional and functional assays in platelets. These results should help the research community make informed choices about platelet isolation techniques in their own platelet studies.


Asunto(s)
Plaquetas , Perfilación de la Expresión Génica , Transcriptoma , Humanos , Plaquetas/metabolismo , Estudios Prospectivos , Perfilación de la Expresión Génica/métodos , Separación Celular/métodos , Antígenos Comunes de Leucocito/metabolismo , Reproducibilidad de los Resultados , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/metabolismo , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/genética , Secuenciación de Nucleótidos de Alto Rendimiento
9.
Nat Aging ; 4(8): 1043-1052, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38834882

RESUMEN

Clonal hematopoiesis of indeterminate potential (CHIP), whereby somatic mutations in hematopoietic stem cells confer a selective advantage and drive clonal expansion, not only correlates with age but also confers increased risk of morbidity and mortality. Here, we leverage genetically predicted traits to identify factors that determine CHIP clonal expansion rate. We used the passenger-approximated clonal expansion rate method to quantify the clonal expansion rate for 4,370 individuals in the National Heart, Lung, and Blood Institute (NHLBI) Trans-Omics for Precision Medicine (TOPMed) cohort and calculated polygenic risk scores for DNA methylation aging, inflammation-related measures and circulating protein levels. Clonal expansion rate was significantly associated with both genetically predicted and measured epigenetic clocks. No associations were identified with inflammation-related lab values or diseases and CHIP expansion rate overall. A proteome-wide search identified predicted circulating levels of myeloid zinc finger 1 and anti-Müllerian hormone as associated with an increased CHIP clonal expansion rate and tissue inhibitor of metalloproteinase 1 and glycine N-methyltransferase as associated with decreased CHIP clonal expansion rate. Together, our findings identify epigenetic and proteomic patterns associated with the rate of hematopoietic clonal expansion.


Asunto(s)
Hematopoyesis Clonal , Epigénesis Genética , Proteómica , Hematopoyesis Clonal/genética , Humanos , Metilación de ADN , Femenino , Masculino , Células Madre Hematopoyéticas/metabolismo , Persona de Mediana Edad , Proteoma/metabolismo , Proteoma/genética , Inhibidor Tisular de Metaloproteinasa-1/genética , Anciano
10.
JCO Oncol Pract ; 20(9): 1252-1262, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38857457

RESUMEN

PURPOSE: Early-phase clinical trials (EP-CTs) are designed to determine optimal dosing, tolerability, and preliminary activity of novel cancer therapeutics. Little is known about the time that patients spend interacting with the health care system (eg, time toxicity) while participating in these studies. METHODS: We retrospectively reviewed the electronic health records of consecutive patients enrolled in EP-CTs from 2017 to 2019 to obtain baseline characteristics and number of health care-associated days, defined as all inpatient and outpatient visits while on trial. We used univariable and multivariable analyses to identify predictors of increased time toxicity, defined as the proportion of health care-associated days among total days on trial. For ease of interpretation, we created a dichotomous variable, with high time toxicity defined as ≥20% health care-associated days during time on trial and used regression models to evaluate relationships between time toxicity and clinical outcomes. RESULTS: Among 408 EP-CT participants (mean age, 60.5 years [standard deviation, SD, 12.6]; 56.5% female; 88.2% White; 96.0% non-Hispanic), patients had an average of 22.5% health care-associated days while on trial (SD, 13.8%). Those with GI (B = 0.07; P = .002), head/neck (B = 0.09; P = .004), and breast (B = 0.06; P = .015) cancers and those with worse performance status (B = 0.04; P = .017) and those receiving targeted therapies (B = 0.04; P = .014) experienced higher time toxicity. High time toxicity was associated with decreased disease response rates (odds ratio, 0.07; P < .001), progression-free survival (hazard ratio [HR], 2.10; P < .001), and overall survival (HR, 2.16; P < .001). CONCLUSION: In this cohort of EP-CT participants, patients spent more than one-fifth of days on trial with health care contact. We identified characteristics associated with higher time toxicity and found that high toxicity correlated with worse clinical outcomes. These data could help inform patient-clinician discussions about EP-CTs, guide future trial design, and identify at-risk patients.


Asunto(s)
Neoplasias , Humanos , Femenino , Masculino , Persona de Mediana Edad , Neoplasias/complicaciones , Estudios Retrospectivos , Ensayos Clínicos como Asunto , Anciano
11.
Hum Mol Genet ; 33(18): 1584-1591, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-38879759

RESUMEN

Venous thromboembolism (VTE) is a significant contributor to morbidity and mortality, with large disparities in incidence rates between Black and White Americans. Polygenic risk scores (PRSs) limited to variants discovered in genome-wide association studies in European-ancestry samples can identify European-ancestry individuals at high risk of VTE. However, there is limited evidence on whether high-dimensional PRS constructed using more sophisticated methods and more diverse training data can enhance the predictive ability and their utility across diverse populations. We developed PRSs for VTE using summary statistics from the International Network against Venous Thrombosis (INVENT) consortium genome-wide association studies meta-analyses of European- (71 771 cases and 1 059 740 controls) and African-ancestry samples (7482 cases and 129 975 controls). We used LDpred2 and PRS-CSx to construct ancestry-specific and multi-ancestry PRSs and evaluated their performance in an independent European- (6781 cases and 103 016 controls) and African-ancestry sample (1385 cases and 12 569 controls). Multi-ancestry PRSs with weights tuned in European-ancestry samples slightly outperformed ancestry-specific PRSs in European-ancestry test samples (e.g. the area under the receiver operating curve [AUC] was 0.609 for PRS-CSx_combinedEUR and 0.608 for PRS-CSxEUR [P = 0.00029]). Multi-ancestry PRSs with weights tuned in African-ancestry samples also outperformed ancestry-specific PRSs in African-ancestry test samples (PRS-CSxAFR: AUC = 0.58, PRS-CSx_combined AFR: AUC = 0.59), although this difference was not statistically significant (P = 0.34). The highest fifth percentile of the best-performing PRS was associated with 1.9-fold and 1.68-fold increased risk for VTE among European- and African-ancestry subjects, respectively, relative to those in the middle stratum. These findings suggest that the multi-ancestry PRS might be used to improve performance across diverse populations to identify individuals at highest risk for VTE.


Asunto(s)
Puntuación de Riesgo Genético , Tromboembolia Venosa , Femenino , Humanos , Masculino , Negro o Afroamericano/genética , Estudios de Casos y Controles , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Polimorfismo de Nucleótido Simple , Tromboembolia Venosa/genética , Tromboembolia Venosa/epidemiología , Blanco/genética
12.
Med Sci Sports Exerc ; 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38913957

RESUMEN

PURPOSE: Platelets are key mediators in cardiovascular disease (CVD). Low cardiorespiratory fitness (CRF) is a risk factor for CVD. The purpose of our study was to assess if CRF associates with platelet function. METHODS: Platelet assays and cardiopulmonary exercise testing were conducted in the Framingham Heart Study (n = 3,014). Linear mixed effects models estimated associations between CRF (assessed by peak oxygen uptake [VO2]), and multiple platelet reactivity assays. Models were adjusted for multiple medications, risk factors, relatedness and prevalent CVD. RESULTS: Nineteen associations passed the significance threshold in the fully adjusted models, all indicating higher CRF associated with decreased platelet reactivity. Significant traits spanned multiple platelet agonists. Strongest associations were observed in Multiplate whole blood testing after TRAP-6 (e.g., velocity, beta = -0.563, 95% CI [-0.735,-0.391], p = 1.38E-10), ADP (e.g., velocity, beta = -0.514, 95% CI [-0.681,-0348], p = 1.41E-09), collagen (e.g., velocity, beta = -0.387, 95% CI [-0.549,-0.224], p = 3.01E-06), ristocetin (e.g., AUC, beta = -0.365, 95% CI [-0.522,-0.208], p = 5.17E-06) and arachidonic acid stimulation of platelets (e.g., velocity, beta = -0.298, 95% CI [-0.435,-0.162], p = 3.39E-04), and light transmission aggregometry (LTA) after ristocetin stimulation (e.g., max aggregation, beta = -0.362, 95% CI [-0.540,-0.184], p = 6.64E-05). One trait passed significance threshold in the aspirin sub-sample (LTA ristocetin primary slope, beta = -0.733, 95% CI [-1.134,-0.333], p = 3.30E-04), and another in a model including von Willebrand Factor levels as a covariate (U46619, a thromboxane receptor mimetic, AUC in the Optimul assay, beta = -0.36, 95%CI [-0.551,-0.168], p = 2.35E-04). No strong interactions were observed between the associations and sex, age or body mass index in formal interaction analyses. CONCLUSIONS: Our findings build on past work that shows CRF to be associated with reduced CVD by suggesting decreased platelet reactivity may play a mechanistic role. We found significant associations with multiple platelet agonists, indicating higher CRF may globally inhibit platelets; however, given multiple strong associations after TRAP-6 and ADP stimulation, PAR-1 and purinergic signaling may be most heavily involved. This is notable since each of these receptor pathways are tied to anti-coagulant (DOACs/thrombin inhibitors) and anti-platelet therapies (P2Y12/PAR1/PAR4 inhibitors) for CVD prevention.

13.
Inorg Chem ; 63(24): 10967-10979, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38832535

RESUMEN

A series of iso-carbamate complexes have been synthesized by the reaction of [SnII(OiPr)2] or [SnII(OtBu)2] with either aryl or alkyl isocyanates, ONC-R (R = 2,4,6-trimethylphenyl (Mes), 2,6-diisopropylphenyl (Dipp), isopropyl (iPr), cyclohexyl (Cy) and tert-butyl (tBu)). In the case of aryl isocyanates, mono-insertion occurs to form structurally characterized complexes [Sn{κ2-N,O-R-NC(OiPr)O}(µ-OiPr)]2 (1: R = Mes, 2: R = Dipp) and [Sn{κ2-N,O-R-NC(OtBu)O}(µ-OtBu)]2 (3: R = Mes, 4: R = Dipp). The complicated solution-state chemistry of these species has been explored using 1H DOSY experiments. In contrast, reactions of tin(II) alkoxides with alkyl isocyanates result in the formation of bis-insertion products [Sn{κ2-N,O-R-NC(OiPr)O}2] (5: R = iPr, and 6: R = Cy) and [Sn{κ2-N,O-R-NC(OtBu)O}2] (7: R = iPr, 8: R = Cy), of which complexes 6-8 have also been structurally characterized. 1H NMR studies show that the reaction of tBu-NCO with either [Sn(OiPr)2] or [Sn(OtBu)2] results in a reversible mono-insertion. Variable-temperature 2D 1H-1H exchange spectroscopy (VT-2D-EXSY) was used to determine the rate of exchange between free tBu-NCO and the coordinated tBu-iso-carbamate ligand for the {OiPr} alkoxide complex, as well as the activation energy (Ea = 92.2 ± 0.8 kJ mol-1), enthalpy (ΔH‡ = 89.4 ± 0.8 kJ mol-1), and entropy (ΔS‡ = 12.6 ± 2.9 J mol-1 K-1) for the process [Sn(OiPr)2] + tBu-NCO ↔ [Sn{κ2-N,O-tBu-NC(OiPr)O}(OiPr)]. Attempts to form Sn(II) alkyl carbonates by the insertion of CO2 into either [Sn(OiPr)2] or [Sn(OtBu)2] proved unsuccessful. However, 119Sn{1H} NMR spectroscopy of the reaction of excess CO2 with [Sn(OiPr)2] reveals the presence of a new Sn(II) species, i.e., [(iPrO)Sn(O2COiPr)], VT-2D-EXSY (1H) of which confirms the reversible alkyl carbonate formation (Ea = 70.3 ± 13.0 kJ mol-1; ΔH‡ = 68.0 ± 1.3 kJ mol-1 and ΔS‡ = -8.07 ± 2.8 J mol-1 K-1).

14.
ACS Appl Mater Interfaces ; 16(26): 33620-33632, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38888466

RESUMEN

Amorphous molybdenum sulfide (a-MoSx) is a promising candidate to replace noble metals as electrocatalysts for the hydrogen evolution reaction (HER) in electrochemical water splitting. So far, understanding of the activity of a-MoSx in relation to its physical (e.g., porosity) and chemical (e.g., Mo/S bonding environments) properties has mostly been derived from bulk electrochemical measurements, which provide limited information about electrode materials that possess microscopic structural heterogeneities. To overcome this limitation, herein, scanning electrochemical cell microscopy (SECCM) has been deployed to characterize the microscopic electrochemical activity of a-MoSx thin films (ca. 200 nm thickness), which possess a significant three-dimensional structure (i.e., intrinsic porosity) when produced by electrodeposition. A novel two-step SECCM protocol is designed to quantitatively determine spatially resolved electrochemical activity and electrochemical surface area (ECSA) within a single, high-throughput measurement. It is shown for the first time that although the highest surface area (e.g., most porous) regions of the a-MoSx film possess the highest total activity (measured by the electrochemical current), they do not possess the highest specific activity (measured by the ECSA-normalized current density). Instead, the areas of highest specific activity are localized at/around circular structures, coined "pockmarks", which are tens to hundreds of micrometers in size and ubiquitous to a-MoSx films produced by electrodeposition. By coupling this technique with structural and elemental composition analysis techniques (scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy) and correlating ECSA with activity and specific activity across SECCM scans, this work furthers the understanding of structure-activity relations in a-MoSx and highlights the importance of local measurements for the systematic and rational design of thin film catalyst materials.

15.
Dalton Trans ; 53(27): 11380-11392, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38896487

RESUMEN

A series of zinc(II) thioamidate complexes [Zn{SC(iPr)NR}2]n for R = iPr (n = 2) (2), tBu (3) (n = 1), Ph (4) (n = 2) and Cy (5) (n = 2) and one cadmium(II) thioamidate complex [Cd{SC(iPr)NtBu}2]3, (6), were designed and synthesised as single-source precursors for AACVD ZnS and CdS. Solid-state structures of all four zinc(II) compounds revealed distorted tetrahedral or trigonal bipyramidal geometries, with varying tendencies for dimeric association, mediated by {Zn-S} bridging bonds. The thermogravimetric analysis identified the {tBu} derivertive, 3, as the most promising precursor based on its low decomposition onset (118 °C) and clean conversion to ZnS. This was attributed to the greater availability of ß-hydrogen atoms promoting the pyrolysis mechanism. The corresponding cadmium thioamide 6 was found to crystallise as a trimetallic molecule which lacked the thermal stability to be considered viable for AACVD. Hence, 3 was used to deposit ZnS thin films by AACVD at 200-300 °C. Powder X-ray diffraction confirmed phase-pure growth of hexagonal wurtzite ZnS, with approximate crystallite sizes of 15-20 nm. Scanning electron microscopy revealed densely packed spherical nanoclusters. The morphology and crystallinity were most consistent for depositions between 250-300 °C. Energy dispersive X-ray spectroscopy indicated slightly sulfur-deficient stoichiometries.

16.
Nat Commun ; 15(1): 3800, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38714703

RESUMEN

Clonal hematopoiesis (CH) is characterized by the acquisition of a somatic mutation in a hematopoietic stem cell that results in a clonal expansion. These driver mutations can be single nucleotide variants in cancer driver genes or larger structural rearrangements called mosaic chromosomal alterations (mCAs). The factors that influence the variations in mCA fitness and ultimately result in different clonal expansion rates are not well understood. We used the Passenger-Approximated Clonal Expansion Rate (PACER) method to estimate clonal expansion rate as PACER scores for 6,381 individuals in the NHLBI TOPMed cohort with gain, loss, and copy-neutral loss of heterozygosity mCAs. Our mCA fitness estimates, derived by aggregating per-individual PACER scores, were correlated (R2 = 0.49) with an alternative approach that estimated fitness of mCAs in the UK Biobank using population-level distributions of clonal fraction. Among individuals with JAK2 V617F clonal hematopoiesis of indeterminate potential or mCAs affecting the JAK2 gene on chromosome 9, PACER score was strongly correlated with erythrocyte count. In a cross-sectional analysis, genome-wide association study of estimates of mCA expansion rate identified a TCL1A locus variant associated with mCA clonal expansion rate, with suggestive variants in NRIP1 and TERT.


Asunto(s)
Aberraciones Cromosómicas , Hematopoyesis Clonal , Mosaicismo , Humanos , Hematopoyesis Clonal/genética , Masculino , Femenino , Estudio de Asociación del Genoma Completo , Janus Quinasa 2/genética , Telomerasa/genética , Telomerasa/metabolismo , Pérdida de Heterocigocidad , Estudios Transversales , Mutación , Persona de Mediana Edad , Células Madre Hematopoyéticas/metabolismo , Polimorfismo de Nucleótido Simple , Anciano
17.
Genetics ; 227(4)2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-38809057

RESUMEN

In F1 hybrids, phenotypic values are expected to be near the parental means under additive effects or close to one parent under dominance. However, F1 traits can fall outside the parental range, and outbreeding depression occurs when inferior fitness is observed in hybrids. Another possible outcome is heterosis, a phenomenon that interspecific hybrids or intraspecific crossbred F1s exhibit improved fitness compared to both parental species or strains. As an application of heterosis, hybrids between channel catfish females and blue catfish males are superior in feed conversion efficiency, carcass yield, and harvestability. Over 20 years of hybrid catfish production in experimental settings and farming practices generated abundant phenotypic data, making it an ideal system to investigate heterosis. In this study, we characterized fitness in terms of growth and survival longitudinally, revealing environment-dependent heterosis. In ponds, hybrids outgrow both parents due to an extra rapid growth phase of 2-4 months in year 2. This bimodal growth pattern is unique to F1 hybrids in pond culture environments only. In sharp contrast, the same genetic types cultured in tanks display outbreeding depression, where hybrids perform poorly, while channel catfish demonstrate superiority in growth throughout development. Our findings represent the first example, known to the authors, of opposite fitness shifts in response to environmental changes in interspecific vertebrate hybrids, suggesting a broader fitness landscape for F1 hybrids. Future genomic studies based on this experiment will help understand genome-environment interaction in shaping the F1 progeny fitness in the scenario of environment-dependent heterosis and outbreeding depression.


Asunto(s)
Interacción Gen-Ambiente , Aptitud Genética , Vigor Híbrido , Hibridación Genética , Vigor Híbrido/genética , Animales , Femenino , Bagres/genética , Bagres/crecimiento & desarrollo , Masculino , Genotipo , Fenotipo
18.
F1000Res ; 13: 134, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38779315

RESUMEN

With the enormous growth in interest and use of generative artificial intelligence (AI) systems seen since the launch of ChatGPT in autumn 2022 have come questions both about the legal status of AI outputs, and of using protected works as training inputs. It is inevitable that UK higher education institution (HEI) library copyright advice services will see an increase in questions around use of works with AI as a result. Staff working in such library services are not lawyers or able to offer legal advice to their academic researchers. Nonetheless, they must look at the issues raised, consider how to advise in analogous situations of using copyright material, and offer opinion to researchers accordingly. While the legal questions remain to be answered definitively, copyright librarians can still offer advice on both open licences and use of copyright material under permitted exceptions. We look here at how library services can address questions on copyright and open licences for generative AI for researchers in UK HEIs.


Asunto(s)
Inteligencia Artificial , Derechos de Autor , Derechos de Autor/legislación & jurisprudencia , Reino Unido , Humanos
19.
Sci Adv ; 10(20): eadl6717, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38748800

RESUMEN

Documenting the seasonal temperature cycle constitutes an essential step toward mitigating risks associated with extreme weather events in a future warmer world. The mid-Piacenzian Warm Period (mPWP), 3.3 to 3.0 million years ago, featured global temperatures approximately 3°C above preindustrial levels. It represents an ideal period for directed paleoclimate reconstructions equivalent to model projections for 2100 under moderate Shared Socioeconomic Pathway SSP2-4.5. Here, seasonal clumped isotope analyses of fossil mollusk shells from the North Sea are presented to test Pliocene Model Intercomparison Project 2 outcomes. Joint data and model evidence reveals enhanced summer warming (+4.3° ± 1.0°C) compared to winter (+2.5° ± 1.5°C) during the mPWP, equivalent to SSP2-4.5 outcomes for future climate. We show that Arctic amplification of global warming weakens mid-latitude summer circulation while intensifying seasonal contrast in temperature and precipitation, leading to an increased risk of summer heat waves and other extreme weather events in Europe's future.


Asunto(s)
Calentamiento Global , Estaciones del Año , Europa (Continente) , Temperatura , Animales , Cambio Climático , Fósiles , Modelos Climáticos
20.
PLoS One ; 19(5): e0302225, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38739607

RESUMEN

Global scallop fisheries are economically important but are associated with environmental impacts to seabed communities resulting from the direct physical contact of the fishing gear with the seabed. Gear modifications attempting to reduce this contact must be economically feasible such that the catch numbers for the target species is maintained or increased. This study investigated the outcome of reducing seabed contact on retained catch of scallops and bycatch by the addition of skids to the bottom of the collecting bag of scallop dredges. We used a paired control experimental design to investigate the impact of the gear modification in different habitat types. The modified skid dredge generally caught more marketable scallops per unit area fished compared with the standard dredge (+5%). However, the skid dredge also retained more bycatch (+11%) and more undersize scallops (+16%). The performance of the two dredges was habitat specific which indicates the importance of adjusting management measures in relation to habitat type. To realize the potential environmental benefits associated with the improvement in catchability of this gear modification, further gear modification is required to reduce the catch of undersize scallops and bycatch. Furthermore we advocate that technical gear innovations in scallop dredging need to be part of a comprehensive and effective fisheries management system.


Asunto(s)
Ecosistema , Explotaciones Pesqueras , Pectinidae , Animales , Conservación de los Recursos Naturales/métodos
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