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1.
Nature ; 589(7843): 532-535, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33505034

RESUMEN

Carbon is the fourth-most prevalent element in the Universe and essential for all known life. In the elemental form it is found in multiple allotropes, including graphite, diamond and fullerenes, and it has long been predicted that even more structures can exist at pressures greater than those at Earth's core1-3. Several phases have been predicted to exist in the multi-terapascal regime, which is important for accurate modelling of the interiors of carbon-rich exoplanets4,5. By compressing solid carbon to 2 terapascals (20 million atmospheres; more than five times the pressure at Earth's core) using ramp-shaped laser pulses and simultaneously measuring nanosecond-duration time-resolved X-ray diffraction, we found that solid carbon retains the diamond structure far beyond its regime of predicted stability. The results confirm predictions that the strength of the tetrahedral molecular orbital bonds in diamond persists under enormous pressure, resulting in large energy barriers that hinder conversion to more-stable high-pressure allotropes1,2, just as graphite formation from metastable diamond is kinetically hindered at atmospheric pressure. This work nearly doubles the highest pressure at which X-ray diffraction has been recorded on any material.

2.
Stem Cells ; 42(4): 317-328, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38227647

RESUMEN

Embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) have unique characteristics where they can both contribute to all three germ layers in vivo and self-renewal indefinitely in vitro. Post-translational modifications of proteins, particularly by the ubiquitin proteasome system (UPS), control cell pluripotency, self-renewal, and differentiation. A significant number of UPS members (mainly ubiquitin ligases) regulate pluripotency and influence ESC differentiation with key elements of the ESC pluripotency network (including the "master" regulators NANOG and OCT4) being controlled by ubiquitination. To further understand the role of the UPS in pluripotency, we performed an RNAi screen during induction of cellular reprogramming and have identified FBXO9 as a novel regulator of pluripotency associated protein DPPA5. Our findings indicate that FBXO9 silencing facilitates the induction of pluripotency through decreased proteasomal degradation of DPPA5. These findings identify FBXO9 as a key regulator of pluripotency.


Asunto(s)
Células Madre Embrionarias , Proteínas F-Box , Complejo de la Endopetidasa Proteasomal , Ubiquitina-Proteína Ligasas , Diferenciación Celular , Reprogramación Celular , Células Madre Embrionarias/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación , Animales , Ratones , Proteínas F-Box/genética , Proteínas F-Box/metabolismo
3.
Reprod Biomed Online ; 49(1): 103976, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38733676

RESUMEN

RESEARCH QUESTION: Can immature oocytes vitrified and warmed using a short protocol survive and resume meiosis? DESIGN: This study examined modifications of oocyte vitrification and warming protocols that reduce the length of exposure to vitrification and warming solutions. In total, 561 germinal vesicles and 218 metaphase I oocytes that were immature at oocyte retrieval were vitrified at room temperature for 2 min. Warming was performed at 37°C for 2 min. Resumption of meiotic activity was evaluated after 24 and 48 h of culture. Two different commercially available vitrification and warming kits were used for comparison. RESULTS: Ninety-five percent of germinal vesicles survived, with no difference observed between the kits. The survival of metaphase I oocytes was, on average, 95.4% and did not differ significantly between the kits. Of the 533 germinal vesicles that survived, 491 converted to metaphase I oocytes (92.1%). After culture for 48 h, 54.4% converted to metaphase II oocytes. In addition, of the 208 metaphase I oocytes that survived warming, 84.1% converted to metaphase II oocytes after 24 h of culture. These maturation rates were similar to those of non-vitrified oocytes. CONCLUSIONS: Vitrification and warming of oocytes at different nuclear maturation stages can be performed with 2 min of exposure to hypertonic solution and 2 min of exposure to hypotonic solution, respectively. This approach reduces exposure of the oocytes to room temperature during dehydration and rehydration. Warming in 0.5M sucrose helps to maintain and support the potential of oocytes to resume nuclear meiotic activity, and conversion from germinal vesicles to metaphase I and metaphase II oocytes.


Asunto(s)
Criopreservación , Meiosis , Oocitos , Vitrificación , Oocitos/citología , Oocitos/fisiología , Humanos , Meiosis/fisiología , Femenino , Criopreservación/métodos , Supervivencia Celular , Técnicas de Maduración In Vitro de los Oocitos/métodos , Adulto
4.
Phys Chem Chem Phys ; 26(7): 6138-6147, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38299662

RESUMEN

Radiation sensors are an important enabling technology in several fields, such as medicine, scientific research, energy, defence, meteorology, and homeland security. Glass-based scintillators have been in use for more than 50 years and offer many benefits, including their ability to respond to different types of radiation, and to be readily formed into various shapes. There is, however, the prospect to develop new and improved glass scintillators, with low self-absorption, low refractive indices, and high radiative recombination rates. To investigate the factors limiting the improvement of glass scintillator properties, this work provides insight from atomic scale simulations of the cerium-doped lithium aluminosilicate (SiO2-Al2O3-MgO-Li2O-Ce2O3) glass scintillator system. Three glass compositions were studied using molecular dynamics and density functional theory to investigate the effect of the ratio (with RAl/M = [0.1, 0.8 and 1.2]) on the structural and electronic properties. For a ratio RAl/M > 1, it has been shown that glasses with increased polymerization allow for more effective incorporation of Ce3+ cations. The structural analysis also showed that the bond order of Al-O can be affected in the presence of a lithium-rich environment. Electronic density of states and Bader charge analysis indicate a decline in the population of localized trapping states with increasing RAl/M. This suggests a higher probability of radiative recombination which can increase the photon yield of these scintillators. These findings provide valuable guidance for optimizing Li-glasses in neutron detection systems by highlighting the intricate challenges.

5.
Anaesthesia ; 79(6): 593-602, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38353045

RESUMEN

Cancellations within 24 h of planned elective surgical procedures reduce operating theatre efficiency, add unnecessary costs and negatively affect patient experience. We implemented a bundle intervention that aimed to reduce same-day case cancellations. This consisted of communication tools to improve patient engagement and new screening instruments (automated estimation of ASA physical status and case cancellation risk score plus four screening questions) to identify patients in advance (ideally before case booking) who needed comprehensive pre-operative risk stratification. We studied patients scheduled for ambulatory surgery with the otorhinolaryngology service at a single centre from April 2021 to December 2022. Multivariable logistic regression and interrupted time-series analyses were used to analyse the effects of this intervention on case cancellations within 24 h and costs. We analysed 1548 consecutive scheduled cases. Cancellation within 24 h occurred in 114 of 929 (12.3%) cases pre-intervention and 52 of 619 (8.4%) cases post-intervention. The cancellation rate decreased by 2.7% (95%CI 1.6-3.7%, p < 0.01) during the first month, followed by a monthly decrease of 0.2% (95%CI 0.1-0.4%, p < 0.01). This resulted in an estimated $150,200 (£118,755; €138,370) or 35.3% cost saving (p < 0.01). Median (IQR [range]) number of days between case scheduling and day of surgery decreased from 34 (21-61 [0-288]) pre-intervention to 31 (20-51 [1-250]) post-intervention (p < 0.01). Patient engagement via the electronic health record patient portal or text messaging increased from 75.9% at baseline to 90.8% (p < 0.01) post-intervention. The primary reason for case cancellation was patients' missed appointment on the day of surgery, which decreased from 7.2% pre-intervention to 4.5% post-intervention (p = 0.03). An anaesthetist-driven, clinical informatics-based bundle intervention decreases same-day case cancellation rate and associated costs in patients scheduled for ambulatory otorhinolaryngology surgery.


Asunto(s)
Procedimientos Quirúrgicos Ambulatorios , Citas y Horarios , Procedimientos Quirúrgicos Otorrinolaringológicos , Humanos , Procedimientos Quirúrgicos Ambulatorios/economía , Masculino , Persona de Mediana Edad , Femenino , Adulto , Anciano , Procedimientos Quirúrgicos Otorrinolaringológicos/economía , Paquetes de Atención al Paciente/economía , Paquetes de Atención al Paciente/métodos , Procedimientos Quirúrgicos Electivos/economía , Análisis de Series de Tiempo Interrumpido
6.
J Dairy Sci ; 107(4): 2499-2511, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37977440

RESUMEN

Monitoring body condition score (BCS) is a useful management tool to estimate the energy reserves of an individual cow or a group of cows. The aim of this study was to develop and evaluate the performance of a fully automated 2-dimensional imaging system using a machine learning algorithm to generate real-time BCS for dairy cows. Two separate datasets were used for training and testing. The training dataset included 34,150 manual BCS (MAN_BCS) assigned by 5 experienced veterinarians during 35 visits at 7 dairy farms. Ordinal regression methods and deep learning architecture were used when developing the algorithm. Subsequently, the testing dataset was used to evaluate the developed BCS prediction algorithm on 4 of the participating farms. An experienced human assessor (HA1) visited these farms and performed 8 whole-milking-herd BCS sessions. Each farm was visited twice, allowing for 30 d (±2 d) to pass between visits. The MAN_BCS assigned by HA1 were considered the ground truth data. At the end of the validation study, MAN_BCS were merged with the stored automated BCS (AI_BCS), resulting in a testing dataset of 9,657 single BCS. A total of 3,817 cows in the testing dataset were scored twice 30 d (±2 d) apart, and the change in their BCS (ΔBCS) was calculated. A subset of cows at one farm were scored twice on consecutive days to evaluate the within-observer agreement of both the human assessor and the system. The manual BCS of 2 more assessors (HA2 and HA3) were used to assess the interobserver agreement between humans. Finally, we also collected ultrasound measurements of backfat thickness (BFT) from 111 randomly selected cows with available MAN_BCS and AI_BCS. Using the testing dataset, intra- and interobserver agreement for single BCS and ΔBCS were estimated by calculating the simple percentage agreement (PA) at 3 error levels and the weighted kappa (κw) for the exact agreement. A Bland-Altman plot was constructed to visualize the systematic and proportional bias. The association between MAN_BCS and AI_BCS and the BFT was assessed with Passing-Bablok regressions. The system had an almost perfect repeatability with a κw of 0.99. The agreement between MAN_BCS and AI_BCS was substantial, with an overall κw of 0.69. The overall PA at the exact, ± 0.25-unit, and ± 0.50-unit BCS error range between MAN_BCS and AI_BCS was 44.4%, 84.6%, and 94.8%, respectively, and greater than the PA obtained between HA1 and HA3. The Bland-Altman plot revealed a minimal systematic bias of -0.09 with a proportional bias at the extreme scores. Furthermore, despite the low κw of 0.20, the overall PA at the exact and ± 0.25-unit of BCS error range between MAN_BCS and AI_BCS regarding the ΔBCS was 45.7 and 88.2%, respectively. A strong linear relationship was observed between BFT and AI_BCS (ρ = 0.75), although weaker than that between BFT and MAN_BCS (ρ = 0.91). The system was able to predict single BCS and ΔBCS with satisfactory accuracy, comparable to that obtained between trained human scorers.


Asunto(s)
Industria Lechera , Aprendizaje Automático , Femenino , Bovinos , Humanos , Animales , Industria Lechera/métodos , Lactancia
7.
Chron Respir Dis ; 21: 14799731241238435, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38553857

RESUMEN

OBJECTIVES: This study aimed to determine the feasibility of a group-based pilot programme of low-to-moderate physical activity training, education and social activities, by investigating acceptability, practicality, implementation and efficacy testing. We offer suggestions on programme adaptions for future study. METHODS: People with a range of chronic respiratory diseases were invited to participate in a pilot 12 week group activity programme. Activities included outdoor walking, tai-chi, education and a range of social activities. Acceptability was determined by participant experiences determined during interviews. Practicality was determined by programme and outcome measure completion, cost and adverse events. Implementation was determined according to whether the programme ran as planned. Efficacy was determined by statistical analyses of outcomes including hand grip strength, timed up and go test, COPD Helplessness Index, COPD Assessment Test, and measures of physical activity via accelerometry. RESULTS: Thematic analysis indicated that the "BreatheHappy" programme was acceptable. Seven of nine participants completed eight out of 10 sessions and the majority completed all outcome measures. "BreatheHappy" was therefore considered practical. The programme was not implemented as planned, with only 10 sessions running rather than the 12 intended. There was a significant increase in daily step counts (MD: 1284 95% CI: 240-2329 p: 0.024 effect size: 0.988), stepping time (MD: 16 min 95% CI: 5-27 min p: 0.011 effect size: 1.36) and daily minutes completing light physical activity (MD: 23 95% CI: 6-38 p: 0.006 effect size: 1.6). However, time spent sitting for ≥30 min but ≤60 min significantly increased (MD: 26 95% CI: 0.2-52 min p: 0.049 effect size: 0.931), showing signs of efficacy and changing physical activity behaviour patterns. DISCUSSION: A 10-week programme of low-moderate physical activity training, education and social activities shows signs of feasibility for future research. Suggested adaptions for future study include using physical activity measures such as daily step count or light physical activity for a primary outcome, and mental health and social health related outcome measures relatable to participant's beneficial experiences of the programme. Recruitment in future studies will try and reach both those less socially active and possibly those who have completed pulmonary rehabilitation (PR). Venues should be close to efficient transport links whilst different frequencies and durations of programme delivery should be trialled. Adequate funding should be provided for both staff running the programme and blinded research staff for outcome measurement.


Asunto(s)
Fuerza de la Mano , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Estudios de Factibilidad , Equilibrio Postural , Estudios de Tiempo y Movimiento , Enfermedad Pulmonar Obstructiva Crónica/rehabilitación , Calidad de Vida
8.
Phys Rev Lett ; 130(7): 076101, 2023 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-36867795

RESUMEN

Silicon (Si) exhibits a rich collection of phase transitions under ambient-temperature isothermal and shock compression. This report describes in situ diffraction measurements of ramp-compressed Si between 40 and 389 GPa. Angle-dispersive x-ray scattering reveals that Si assumes an hexagonal close-packed (hcp) structure between 40 and 93 GPa and, at higher pressure, a face-centered cubic structure that persists to at least 389 GPa, the highest pressure for which the crystal structure of Si has been investigated. The range of hcp stability extends to higher pressures and temperatures than predicted by theory.

9.
Trends Immunol ; 41(12): 1128-1140, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33160841

RESUMEN

Hematopoiesis is responsible for numerous functions, ranging from oxygen transportation to host defense, to injury repair. This process of hematopoiesis is maintained throughout life by hematopoietic stem cells and requires a controlled balance between self-renewal, differentiation, and quiescence. Disrupting this balance can result in hematopoietic malignancies, including anemia, immune deficiency, leukemia, and lymphoma. Recent work has shown that FBOX E3 ligases, a substrate recognition component of the ubiquitin proteasome system (UPS), have an integral role in maintaining this balance. In this review, we detail how FBOX proteins target specific proteins for degradation to regulate hematopoiesis through cell processes, such as cell cycle, development, and apoptosis.


Asunto(s)
Hematopoyesis , Proteolisis , Ubiquitina-Proteína Ligasas , Proteínas F-Box/metabolismo , Hematopoyesis/genética , Células Madre Hematopoyéticas , Humanos , Complejo de la Endopetidasa Proteasomal/metabolismo , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo
10.
Inorg Chem ; 62(30): 12027-12037, 2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37466301

RESUMEN

A new reduced phase derived from the excitonic insulator candidate Ta2NiSe5 has been synthesized via the intercalation of lithium. LiTa2NiSe5 crystallizes in the orthorhombic space group Pmnb (no. 62) with lattice parameters a = 3.50247(3) Å, b = 13.4053(4) Å, c = 15.7396(2) Å, and Z = 4, with an increase of the unit cell volume by 5.44(1)% compared with Ta2NiSe5. Significant rearrangement of the Ta-Ni-Se layers is observed, in particular a very significant relative displacement of the layers compared to the parent phase, similar to that which occurs under hydrostatic pressure. Neutron powder diffraction experiments and computational analysis confirm that Li occupies a distorted triangular prismatic site formed by Se atoms of adjacent Ta2NiSe5 layers with an average Li-Se bond length of 2.724(2) Å. Li-NMR experiments show a single Li environment at ambient temperature. Intercalation suppresses the distortion to monoclinic symmetry that occurs in Ta2NiSe5 at 328 K and that is believed to be driven by the formation of an excitonic insulating state. Magnetometry data show that the reduced phase has a smaller net diamagnetic susceptibility than Ta2NiSe5 due to the enhancement of the temperature-independent Pauli paramagnetism caused by the increased density of states at the Fermi level evident also from the calculations, consistent with the injection of electrons during intercalation and formation of a metallic phase.

11.
Epidemiol Infect ; 151: e187, 2023 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-37876041

RESUMEN

SNP addresses are a pathogen typing method based on whole-genome sequences (WGSs), assigning groups at seven different levels of genetic similarity. Public health surveillance uses it for several gastro-intestinal infections; this work trialled its use in veterinary surveillance for salmonella outbreak detection. Comparisons were made between temporal and spatio-temporal cluster detection models that either defined cases by their SNP address or by phage type, using historical data sets. Clusters of SNP incidents were effectively detected by both methods, but spatio-temporal models consistently detected these clusters earlier than the corresponding temporal models. Unlike phage type, SNP addresses appeared spatially and temporally limited, which facilitated the differentiation of novel, stable, or expanding clusters in spatio-temporal models. Furthermore, these models flagged spatio-temporal clusters containing only two to three cases at first detection, compared with a median of seven cases in phage-type models. The large number of SNP addresses will require automated methods to implement these detection models routinely. Further work is required to explore how temporal changes and different host species may impact the sensitivity and specificity of cluster detection. In conclusion, given validation with more sequencing data, SNP addresses are likely to be a valuable addition to early warning systems in veterinary surveillance.


Asunto(s)
Infecciones por Salmonella , Salmonella typhimurium , Humanos , Salmonella typhimurium/genética , Infecciones por Salmonella/epidemiología , Brotes de Enfermedades/veterinaria , Secuenciación Completa del Genoma , Vigilancia en Salud Pública
12.
Ultrasound Obstet Gynecol ; 62(1): 23-41, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36647238

RESUMEN

OBJECTIVE: To determine the prevalence of adenomyosis in women with subfertility. METHODS: A systematic search was conducted in MEDLINE, EMBASE, CINAHL Plus, Google Scholar, PsycINFO and Web of Science Core Collection from database inception to October 2022. The included studies evaluated the prevalence of adenomyosis in women with subfertility, with or without endometriosis and/or uterine fibroids. Secondary analyses were conducted to identify variation in the prevalence of isolated adenomyosis according to geographical location, diagnostic modality, diagnostic criteria, type of ultrasound, ultrasound features of adenomyosis and the use of assisted reproductive technology. RESULTS: Among 21 longitudinal studies evaluating 25 600 women, the overall pooled prevalence of isolated adenomyosis was 10% (95% CI, 6-15%) (I2 = 99.1%; tau2 = 0.12). The pooled prevalence was 1% (95% CI, 0-4%) for adenomyosis with concurrent fibroids (eight studies; I2 = 95.8%; tau2 = 0.03), 6% (95% CI, 3-11%) for adenomyosis with concurrent endometriosis (18 studies; I2 = 98.6%; tau2 = 0.12) and 7% (95% CI, 2-13%) for adenomyosis with concurrent endometriosis and/or fibroids (nine studies; I2 = 98.3%; tau2 = 0.09). The prevalence of isolated adenomyosis varied substantially according to geographical location, with Australia exhibiting the highest pooled prevalence of adenomyosis (19% (95% CI, 12-27%)), which was significantly higher compared with that in Asia (5% (95% CI, 1-12%)). The pooled prevalence of isolated adenomyosis diagnosed using a combination of direct and indirect ultrasound features was 11% (95% CI, 7-16%), whereas it was 0.45% (95% CI, 0-1%) in the study in which only an indirect feature was used as the diagnostic criterion. CONCLUSION: One in 10 women with subfertility have a diagnosis of isolated adenomyosis. The prevalence of adenomyosis varies according to the presence of concurrent endometriosis and/or fibroids. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Adenomiosis , Endometriosis , Infertilidad , Leiomioma , Embarazo , Femenino , Humanos , Adenomiosis/complicaciones , Adenomiosis/diagnóstico por imagen , Adenomiosis/epidemiología , Endometriosis/complicaciones , Endometriosis/diagnóstico por imagen , Endometriosis/epidemiología , Prevalencia , Leiomioma/complicaciones , Leiomioma/diagnóstico por imagen , Leiomioma/epidemiología
14.
Clin Radiol ; 78(7): 540-547, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37085340

RESUMEN

AIM: To summarise published evidence assessing the preoperative diagnostic performance of identifying inferior vena cava (IVC) wall invasion in patients with renal cell carcinoma (RCC). MATERIALS AND METHODS: A systematic approach was used to identify studies that assessed IVC wall invasion with non-invasive imaging preoperatively. Search limits included English language and human study participants. A meta-analysis was conducted using random effects models to compare radiographic vascular size parameters and the association of IVC wall invasion. RESULTS: A total of 15 studies were identified, which included computed tomography (CT), magnetic resonance imaging (MRI), positron-emission tomography (PET), and ultrasound assessment. In the majority of cases, CT and MRI was utilised with high accuracy in predicting IVC wall invasion. A meta-analysis of commonly reported radiographic vascular size parameters found that IVC wall invasion was associated with greater IVC maximum anteroposterior (AP) diameter (mean difference [MD] = 6.58 mm, 95% confidence interval [CI]: 2.84-10.33, p=0.0006) and IVC maximum AP diameter at the level of the renal vein ostium (MD = 5.69 mm, 95% CI: 4.35-7.03, p<0.0001). Renal vein maximum AP dimension was not associated with IVC wall invasion (MD = 2.56 mm, 95% CI: -0.46-5.58, p=0.10). CONCLUSION: Multi-technique work-up, specifically CT and MRI and reporting of vascular radiographic parameters, of RCC patients with IVC tumour thrombus may be useful in predicting IVC wall invasion, thereby allowing appropriate surgical planning and patient education.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Trombosis , Trombosis de la Vena , Humanos , Carcinoma de Células Renales/diagnóstico por imagen , Carcinoma de Células Renales/cirugía , Neoplasias Renales/diagnóstico por imagen , Neoplasias Renales/cirugía , Vena Cava Inferior/diagnóstico por imagen , Vena Cava Inferior/patología , Estudios Retrospectivos , Trombosis de la Vena/patología , Imagen por Resonancia Magnética/métodos , Nefrectomía/métodos , Trombectomía/métodos
15.
J Dairy Sci ; 106(11): 8087-8097, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37562647

RESUMEN

The objectives of this observational cohort study were to assess the effect of body condition score change, back fat depth change, and muscle diameter change on the time to commencement of luteal activity and first estrus in commercial pedigree Holstein cows. A total of 140 of 200 commercial pedigree Holstein cows were enrolled in one dairy herd in Somerset, UK, over 52 wk in 2021 to 2022. The herd used 4 automatic milking machines with in-line progesterone measurement capability to determine commencement of luteal activity and time to first estrus. Cows were followed until at least 60 d postpartum, and milk progesterone was measured daily starting from 10 DIM. Body condition scoring and ultrasound measurements of back fat depth and longissimus dorsi muscle diameter were performed on cows twice, within 7 d of both calving and 60 DIM. Other explanatory variables assessed included parity, 60-d and 305-d milk yield, and subclinical ketosis (ß-hydroxybutryate ≥1.2 mmol/L). Occurrence of clinical disease <60 DIM was forced into all models as a binary variable. Data were analyzed using multivariable Cox proportionate survival analyses. Muscle loss was associated with commencement of luteal activity and time to first estrus. A reduction in muscle diameter by 1.5 to 5 mm was associated with the shortest time to the start of luteal activity and first estrus. A reduction in muscle diameter >8 mm was associated with the longest times to luteal activity and first estrus. In addition to being affected by muscle loss, commencement of luteal activity was delayed by subclinical ketosis, clinical disease, and failure to gain body condition to 60 DIM. Cows that had a BCS loss of 0.25 or more between calving and 60 DIM were at least 52 ± 22% less likely to have commenced luteal activity compared with those that gained BCS. Interestingly, cows that had no change in body condition score commenced luteal activity later than those that gained body condition score. Muscle loss was associated with time to first estrus irrespective of clinical disease status. Cows that lost >8 mm of muscle diameter showed estrus behavior later than cows that lost 1.5 to 5 mm. In conclusion, our findings indicate that extensive muscle loss postpartum was associated with a delayed start to luteal activity and first estrus, irrespective of body condition change, clinical disease, and subclinical ketosis. Marginal muscle loss and a gain in body condition, however, were associated with an earlier start to luteal activity and first estrus.

16.
Environ Monit Assess ; 195(3): 425, 2023 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-36826723

RESUMEN

Coastal upland forests are facing widespread mortality as sea-level rise accelerates and precipitation and storm regimes change. The loss of coastal forests has significant implications for the coastal carbon cycle; yet, predicting mortality likelihood is difficult due to our limited understanding of disturbance impacts on coastal forests. The manipulative, ecosystem-scale Terrestrial Ecosystem Manipulation to Probe the Effects of Storm Treatments (TEMPEST) experiment addresses the potential for freshwater and estuarine-water disturbance events to alter tree function, species composition, and ecosystem processes in a deciduous coastal forest in MD, USA. The experiment uses a large-unit (2000 m2), un-replicated experimental design, with three 50 m × 40 m plots serving as control, freshwater, and estuarine-water treatments. Transient saturation (5 h) of the entire soil rooting zone (0-30 cm) across a 2000 m2 coastal forest was attained by delivering 300 m3 of water through a spatially distributed irrigation network at a rate just above the soil infiltration rate. Our water delivery approach also elevated the water table (typically ~ 2 m belowground) and achieved extensive, low-level inundation (~ 8 cm standing water). A TEMPEST simulation approximated a 15-cm rainfall event and based on historic records, was of comparable intensity to a 10-year storm for the area. This characterization was supported by showing that Hurricane Ida's (~ 5 cm rainfall) hydrologic impacts were shorter (40% lower duration) and less expansive (80% less coverage) than those generated through experimental manipulation. Future work will apply TEMPEST treatments to evaluate coastal forest resilience to changing hydrologic disturbance regimes and identify conditions that initiate ecosystem state transitions.


Asunto(s)
Ecosistema , Suelo , Monitoreo del Ambiente , Bosques , Agua Dulce
17.
Society ; 60(1): 54-67, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36406240

RESUMEN

In 2015, Pittsburgh had the 21st highest murder rate in the USA at 18.6 murders per 100,000 population. By 2022, its murder rate had declined to 12.32 per 100,000, ranking it number 58 among American cities with greater than 100,000 residents. The article's principal concern is with identifying factors that may have contributed to mitigations of gun violence in metro-Pittsburgh, and especially with how local anti-violence mobilizations within and between key sectors may have contributed to these violence reductions. Activist cadres of youth, social service organizations, governmental decision-makers, foundation leaders, and faith leaders are examined, with attention to how their respective sectors may have been pushed beyond established scopes of concern to take up the fight against gun violence. Drawing upon original interview data from 30 local leaders and from published formal statements and policy issuances from relevant institutional sectors, the article investigates Pittsburgh gun violence and responses, emphasizing the importance of strategically positioned leaders who possessed commitments and capabilities to leverage Pittsburgh's ample institutional resources on behalf of anti-gun violence objectives.

18.
Kidney Int ; 101(2): 288-298, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34757124

RESUMEN

Interstitial fibrosis, tubular atrophy, and inflammation are major contributors to kidney allograft failure. Here we sought an objective, quantitative pathological assessment of these lesions to improve predictive utility and constructed a deep-learning-based pipeline recognizing normal vs. abnormal kidney tissue compartments and mononuclear leukocyte infiltrates. Periodic acid- Schiff stained slides of transplant biopsies (60 training and 33 testing) were used to quantify pathological lesions specific for interstitium, tubules and mononuclear leukocyte infiltration. The pipeline was applied to the whole slide images from 789 transplant biopsies (478 baseline [pre-implantation] and 311 post-transplant 12-month protocol biopsies) in two independent cohorts (GoCAR: 404 patients, AUSCAD: 212 patients) of transplant recipients to correlate composite lesion features with graft loss. Our model accurately recognized kidney tissue compartments and mononuclear leukocytes. The digital features significantly correlated with revised Banff 2007 scores but were more sensitive to subtle pathological changes below the thresholds in the Banff scores. The Interstitial and Tubular Abnormality Score (ITAS) in baseline samples was highly predictive of one-year graft loss, while a Composite Damage Score in 12-month post-transplant protocol biopsies predicted later graft loss. ITASs and Composite Damage Scores outperformed Banff scores or clinical predictors with superior graft loss prediction accuracy. High/intermediate risk groups stratified by ITASs or Composite Damage Scores also demonstrated significantly higher incidence of estimated glomerular filtration rate decline and subsequent graft damage. Thus, our deep-learning approach accurately detected and quantified pathological lesions from baseline or post-transplant biopsies and demonstrated superior ability for prediction of post-transplant graft loss with potential application as a prevention, risk stratification or monitoring tool.


Asunto(s)
Aprendizaje Profundo , Trasplante de Riñón , Biopsia , Rechazo de Injerto/patología , Supervivencia de Injerto , Humanos , Riñón/patología , Trasplante de Riñón/efectos adversos
19.
Proc Biol Sci ; 289(1989): 20221649, 2022 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-36515119

RESUMEN

Ecosystem structure and function are increasingly threatened by changing climate, with profound effects observed globally in recent decades. Based on standardized visual censuses of reef biodiversity, we describe 27 years of community-level change for fishes, mobile macroinvertebrates and macroalgae in the Tasmanian ocean-warming hotspot. Significant ecological change was observed across 94 reef sites (5-10 m depth range) spanning four coastal regions between three periods (1992-95, 2006-07, 2017-19), which occurred against a background of pronounced sea temperature rise (+0.80°C on average). Overall, fish biomass increased, macroinvertebrate species richness and abundance decreased and macroalgal cover decreased, particularly during the most recent decade. While reef communities were relatively stable and warming was slight between the 1990s and mid-2000s (+0.12°C mean temperature rise), increased abundances of warm affinity fishes and invertebrates accompanied warming during the most recent decade (+0.68°C rise). However, significant rises in the community temperature index (CTI) were only found for fishes, invertebrates and macroalgae in some regions. Coastal warming was associated with increased fish biomass of non-targeted species in fished zones but had little effect on reef communities within marine reserves. Higher abundances of larger fishes and lobsters inside reserves appeared to negate impacts of 'thermophilization'.


Asunto(s)
Ecosistema , Algas Marinas , Animales , Biodiversidad , Invertebrados , Temperatura , Peces , Arrecifes de Coral
20.
J Synchrotron Radiat ; 29(Pt 5): 1284-1291, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-36073888

RESUMEN

The development, construction, and first commissioning results of a new scanning microscope installed at the 5-ID Submicron Resolution X-ray Spectroscopy (SRX) beamline at NSLS-II are reported. The developed system utilizes Kirkpatrick-Baez mirrors for X-ray focusing. The instrument is designed to enable spectromicroscopy measurements in 2D and 3D with sub-200 nm spatial resolution. The present paper focuses on the design aspects, optical considerations, and specifics of the sample scanning stage, summarizing some of the initial commissioning results.

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