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1.
Phys Rev Lett ; 132(6): 065104, 2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38394572

RESUMEN

As fusion experiments at the National Ignition Facility (NIF) approach and exceed breakeven, energy from the burning capsule is predicted to couple to the gold walls and reheat the hohlraum. On December 5, 2022, experiment N221204 exceeded target breakeven, historically achieving 3.15 MJ of fusion energy from 2.05 MJ of laser drive; for the first time, energy from the igniting capsule reheated the hohlraum beyond the peak laser-driven radiation temperature of 313 eV to a peak of 350 eV, in less than half a nanosecond. This reheating effect has now been unambiguously observed by the two independent Dante calorimeter systems across multiple experiments, and is shown to result from reheating of the remnant tungsten-doped ablator by the exploding core, which is heated by alpha deposition.

2.
Langmuir ; 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38918081

RESUMEN

The friction of solids is primarily understood through the adhesive interactions between the surfaces. As a result, slick materials tend to be nonstick (e.g., Teflon), and sticky materials tend to produce high friction (e.g., tires and tape). Paradoxically, cartilage, the slippery bearing material of human joints, is also among the stickiest of known materials. This study aims to elucidate this apparent paradox. Cartilage is a biphasic material, and the most cited explanation is that both friction and adhesion increase as load transfers from the pressurized interstitial fluid to the solid matrix over time. In other words, cartilage is slippery and sticky under different times and conditions. This study challenges this explanation, demonstrating the strong adhesion of cartilage under high and low interstitial hydration conditions. Additionally, we find that cartilage clings to itself (a porous material) and Teflon (a nonstick material), as well as other surfaces. We conclude that the unusually strong interfacial tension produced by cartilage reflects suction (like a clingfish) rather than adhesion (like a gecko). This finding is surprising given its unusually large roughness, which typically allows for easy interfacial flow and defeats suction. The results provide compelling evidence that cartilage, like a clingfish, conforms to opposing surfaces and effectively seals submerged contacts. Further, we argue that interfacial sealing is itself a critical function, enabling cartilage to retain hydration, load support, and lubrication across long periods of inactivity.

3.
Nature ; 555(7695): 237-241, 2018 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-29516998

RESUMEN

Laboratory experiments and seismology data have created a clear theoretical picture of the most abundant minerals that comprise the deeper parts of the Earth's mantle. Discoveries of some of these minerals in 'super-deep' diamonds-formed between two hundred and about one thousand kilometres into the lower mantle-have confirmed part of this picture. A notable exception is the high-pressure perovskite-structured polymorph of calcium silicate (CaSiO3). This mineral-expected to be the fourth most abundant in the Earth-has not previously been found in nature. Being the dominant host for calcium and, owing to its accommodating crystal structure, the major sink for heat-producing elements (potassium, uranium and thorium) in the transition zone and lower mantle, it is critical to establish its presence. Here we report the discovery of the perovskite-structured polymorph of CaSiO3 in a diamond from South African Cullinan kimberlite. The mineral is intergrown with about six per cent calcium titanate (CaTiO3). The titanium-rich composition of this inclusion indicates a bulk composition consistent with derivation from basaltic oceanic crust subducted to pressures equivalent to those present at the depths of the uppermost lower mantle. The relatively 'heavy' carbon isotopic composition of the surrounding diamond, together with the pristine high-pressure CaSiO3 structure, provides evidence for the recycling of oceanic crust and surficial carbon to lower-mantle depths.

4.
J Endocrinol Invest ; 47(7): 1667-1677, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38191946

RESUMEN

PURPOSE: The aim of this study was to evaluate changes in hip geometry parameters following treatment with teriparatide (TPD), denosumab (Dmab) and zoledronate (ZOL) in real-life setting. METHODS: We studied 249 patients with osteoporosis (OP) with mean [SD] age of 71.5 [11.1] years divided into 3 treatment groups; Group A received TPD; n = 55, Group B (Dmab); n = 116 and Group C (ZOL); n = 78 attending a routine metabolic bone clinic. Bone mineral density (BMD) was measured by DXA at the lumbar spine (LS), total hip (TH) and femoral neck (FN) prior to treatment and after 2 years (Group A), after a mean treatment duration of 3.3 [1.3] years (Group B) and after 1, 2 and 3 doses of ZOL (Group C) to assess treatment response. Hip structural analysis (HSA) was carried out retrospectively from DXA-acquired femur images at the narrow neck (NN), the intertrochanter (IT) and femoral shaft (FS). RESULTS: Changes in parameters of hip geometry and mechanical strength were seen in the following treatment. Percentage change in cross-sectional area (CSA): 3.56[1.6] % p = 0.01 and cross-sectional moment of inertia (CSMI): 4.1[1.8] % p = 0.029 increased at the NN only in Group A. Improvement in HSA parameters at the IT were seen in group B: CSA: 3.3[0.67]% p < 0.001, cortical thickness (Co Th): 2.8[0.78]% p = 0.001, CSMI: 5.9[1.3]% p < 0.001, section modulus (Z):6.2[1.1]% p < 0.001 and buckling ratio (BR): - 3.0[0.86]% p = 0.001 with small changes at the FS: CSA: 1.2[0.4]% p = 0.005, Z:1.6 [0.76]%, p = 0.04. Changes at the IT were also seen in Group C (after 2 doses): CSA: 2.5[0.77]% p = 0.017, Co Th: 2.4[0.84]% p = 0.012, CSMI: 3.9[1.3]% p = 0.017, Z:5.2[1.16]% p < 0.001 and BR: - 3.1[0.88]% p = 0.001 and at the NN (following 3 doses): outer diameter (OD): 4.0[1.4]% p = 0.0005, endocortical diameter(ED): 4.3[1.67% p = 0.009, CSA:5.2[1.8]% p = 0.003, CSMI: 9.3[3.8]% p = 0.019. CONCLUSIONS: Analysis of the effect of OP therapies on hip geometry is useful in understanding the mechanisms of their anti-fracture effect and may provide additional information on their efficacy.


Asunto(s)
Conservadores de la Densidad Ósea , Densidad Ósea , Denosumab , Osteoporosis , Teriparatido , Ácido Zoledrónico , Humanos , Femenino , Ácido Zoledrónico/uso terapéutico , Ácido Zoledrónico/administración & dosificación , Ácido Zoledrónico/farmacología , Teriparatido/uso terapéutico , Teriparatido/administración & dosificación , Teriparatido/farmacología , Anciano , Conservadores de la Densidad Ósea/uso terapéutico , Conservadores de la Densidad Ósea/administración & dosificación , Densidad Ósea/efectos de los fármacos , Masculino , Denosumab/uso terapéutico , Denosumab/administración & dosificación , Osteoporosis/tratamiento farmacológico , Osteoporosis/patología , Estudios Retrospectivos , Absorciometría de Fotón , Difosfonatos/uso terapéutico , Difosfonatos/administración & dosificación , Persona de Mediana Edad , Anciano de 80 o más Años , Estudios de Seguimiento
5.
J Med Genet ; 60(12): 1235-1244, 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-37558402

RESUMEN

BACKGROUND: Current clinical testing methods used to uncover the genetic basis of rare disease have inherent limitations, which can lead to causative pathogenic variants being missed. Within the rare disease arm of the 100 000 Genomes Project (100kGP), families were recruited under the clinical indication 'single autosomal recessive mutation in rare disease'. These participants presented with strong clinical suspicion for a specific autosomal recessive disorder, but only one suspected pathogenic variant had been identified through standard-of-care testing. Whole genome sequencing (WGS) aimed to identify cryptic 'second-hit' variants. METHODS: To investigate the 31 families with available data that remained unsolved following formal review within the 100kGP, SVRare was used to aggregate structural variants present in <1% of 100kGP participants. Small variants were assessed using population allele frequency data and SpliceAI. Literature searches and publicly available online tools were used for further annotation of pathogenicity. RESULTS: Using these strategies, 8/31 cases were solved, increasing the overall diagnostic yield of this cohort from 10/41 (24.4%) to 18/41 (43.9%). Exemplar cases include a patient with cystic fibrosis harbouring a novel exonic LINE1 insertion in CFTR and a patient with generalised arterial calcification of infancy with complex interlinked duplications involving exons 2-6 of ENPP1. Although ambiguous by short-read WGS, the ENPP1 variant structure was resolved using optical genome mapping and RNA analysis. CONCLUSION: Systematic examination of cryptic variants across a multi-disease cohort successfully identifies additional pathogenic variants. WGS data analysis in autosomal recessive rare disease should consider complex structural and small intronic variants as potentially pathogenic second hits.


Asunto(s)
Enfermedades Raras , Humanos , Mutación/genética , Secuencia de Bases , Exones , Mapeo Cromosómico
6.
BMC Anesthesiol ; 24(1): 156, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38654164

RESUMEN

INTRODUCTION: There is a sizable niche for a minimally invasive analgesic technique that could facilitate ambulatory video-assisted thoracoscopic surgery (VATS). Our study aimed to determine the analgesic potential of a single-shot erector spinae plane (ESP) block for VATS. The primary objective was the total hydromorphone consumption with patient-controlled analgesia (PCA) 24 h after surgery. METHODS: We conducted a randomized, controlled, double-blind study with patients scheduled for VATS in two major university-affiliated hospital centres. We randomized 52 patients into two groups: a single-shot ESP block using bupivacaine or an ESP block with normal saline (control). We administered a preoperative and postoperative (24 h) quality of recovery (QoR-15) questionnaire and assessed postoperative pain using a verbal numerical rating scale (VNRS) score. We evaluated the total standardized intraoperative fentanyl administration, total postoperative hydromorphone consumption (PCA; primary endpoint), and the incidence of adverse effects. RESULTS: There was no difference in the primary objective, hydromorphone consumption at 24 h (7.6 (4.4) mg for the Bupivacaine group versus 8.1 (4.2) mg for the Control group). Secondary objectives and incidence of adverse events were not different between the two groups at any time during the first 24 h following surgery. CONCLUSION: Our multi-centre randomized, controlled, double-blinded study found no advantage of an ESP block over placebo for VATS for opioid consumption, pain, or QoR-15 scores. Further studies are ongoing to establish the benefits of using a denser block (single-shot paravertebral with a continuous ESP block), which may provide a better quality of analgesia.


Asunto(s)
Bloqueo Nervioso , Dolor Postoperatorio , Cirugía Torácica Asistida por Video , Humanos , Método Doble Ciego , Cirugía Torácica Asistida por Video/métodos , Dolor Postoperatorio/prevención & control , Dolor Postoperatorio/tratamiento farmacológico , Masculino , Bloqueo Nervioso/métodos , Femenino , Persona de Mediana Edad , Analgesia Controlada por el Paciente/métodos , Analgésicos Opioides/administración & dosificación , Analgésicos Opioides/uso terapéutico , Anciano , Bupivacaína/administración & dosificación , Anestésicos Locales/administración & dosificación , Músculos Paraespinales , Hidromorfona/administración & dosificación , Adulto
7.
Photosynth Res ; 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37910331

RESUMEN

Hybrid complexes incorporating synthetic Mn-porphyrins into an artificial four-helix bundle domain of bacterial reaction centers created a system to investigate new electron transfer pathways. The reactions were initiated by illumination of the bacterial reaction centers, whose primary photochemistry involves electron transfer from the bacteriochlorophyll dimer through a series of electron acceptors to the quinone electron acceptors. Porphyrins with diphenyl, dimesityl, or fluorinated substituents were synthesized containing either Mn or Zn. Electrochemical measurements revealed potentials for Mn(III)/Mn(II) transitions that are ~ 0.4 V higher for the fluorinated Mn-porphyrins than the diphenyl and dimesityl Mn-porphyrins. The synthetic porphyrins were introduced into the proteins by binding to a four-helix bundle domain that was genetically fused to the reaction center. Light excitation of the bacteriochlorophyll dimer of the reaction center resulted in new derivative signals, in the 400 to 450 nm region of light-minus-dark spectra, that are consistent with oxidation of the fluorinated Mn(II) porphyrins and reduction of the diphenyl and dimesityl Mn(III) porphyrins. These features recovered in the dark and were not observed in the Zn(II) porphyrins. The amplitudes of the signals were dependent upon the oxidation/reduction midpoint potentials of the bacteriochlorophyll dimer. These results are interpreted as photo-induced charge-separation processes resulting in redox changes of the Mn-porphyrins, demonstrating the utility of the hybrid artificial reaction center system to establish design guidelines for novel electron transfer reactions.

8.
Phys Rev Lett ; 131(6): 065101, 2023 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-37625041

RESUMEN

The change in the power balance, temporal dynamics, emission weighted size, temperature, mass, and areal density of inertially confined fusion plasmas have been quantified for experiments that reach target gains up to 0.72. It is observed that as the target gain rises, increased rates of self-heating initially overcome expansion power losses. This leads to reacting plasmas that reach peak fusion production at later times with increased size, temperature, mass and with lower emission weighted areal densities. Analytic models are consistent with the observations and inferences for how these quantities evolve as the rate of fusion self-heating, fusion yield, and target gain increase. At peak fusion production, it is found that as temperatures and target gains rise, the expansion power loss increases to a near constant ratio of the fusion self-heating power. This is consistent with models that indicate that the expansion losses dominate the dynamics in this regime.

9.
Phys Rev Lett ; 129(27): 275001, 2022 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-36638294

RESUMEN

We present measurements of ice-ablator mix at stagnation of inertially confined, cryogenically layered capsule implosions. An ice layer thickness scan with layers significantly thinner than used in ignition experiments enables us to investigate mix near the inner ablator interface. Our experiments reveal for the first time that the majority of atomically mixed ablator material is "dark" mix. It is seeded by the ice-ablator interface instability and located in the relatively cooler, denser region of the fuel assembly surrounding the fusion hot spot. The amount of dark mix is an important quantity as it is thought to affect both fusion fuel compression and burn propagation when it turns into hot mix as the burn wave propagates through the initially colder fuel region surrounding an igniting hot spot. We demonstrate a significant reduction in ice-ablator mix in the hot-spot boundary region when we increase the initial ice layer thickness.

10.
Vet Pathol ; 59(5): 787-791, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35400242

RESUMEN

Three dogs under 12 months old were diagnosed with atypical multiple myeloma (MM), having an aggressive multifocal anaplastic round cell sarcoma in bone marrow, viscera, and/or peripheral blood, which were confirmed by cytology and immunohistochemistry to be of plasma cell origin. The intramedullary sarcomas caused myelophthisis, osteolysis, and hypercalcemia. Complete or free light chain monoclonal gammopathy in the serum and/or urine was demonstrated by protein electrophoresis and immunofixation. The polymerase chain reaction for antigen receptor rearrangement assay performed on 2 cases identified a clonally rearranged immunoglobulin gene. Neoplastic cells lacked expression of CD45, CD3, CD18, CD21, CD34, and MHCII by flow cytometry. Immunohistochemistry revealed MUM1 immunoreactivity of the neoplastic cells. Combining all data, the diagnosis was MM. An aggressive form of MM in young dogs should be a differential diagnosis for patients with an immunoglobulin-productive, B cell-clonal, CD45-negative, MUM1-positive discrete cell neoplasm arising from the bone marrow.


Asunto(s)
Enfermedades de los Perros , Mieloma Múltiple , Animales , Linfocitos B , Médula Ósea , Enfermedades de los Perros/diagnóstico , Perros , Citometría de Flujo/veterinaria , Mieloma Múltiple/diagnóstico , Mieloma Múltiple/veterinaria , Células Plasmáticas
11.
J Dairy Sci ; 105(1): 877-888, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34656349

RESUMEN

The aim of this study was to determine the association between occurrence and intensity of estrous expression with pregnancy success in recipient lactating dairy cows subjected to embryo transfer (ET). Two observational studies were conducted. Holstein cows were synchronized using the same timed ET protocol, based on estradiol and progesterone in both experiments. At 9 d after the end of the timed ET protocol only animals that had ovulated were implanted with a 7-d embryo [experiment 1 (Exp. 1); n = 1,401 ET events from 1,045 cows, and experiment 2 (Exp. 2); n = 1,147 ET events from 657 cows]. Embryos were produced in vivo (Exp. 1 and Exp. 2) and in vitro (only Exp. 2), then transferred to recipient cows as fresh or frozen-thawed. Pregnancy was confirmed at 29 and 58 d after the end of timed ET protocol. In Exp. 1, animals had their estrous expression monitored through a tail chalk applied on the tail head of the cows and evaluated daily for chalk removal (no estrus: 100% of chalk remaining; estrus: <50% of chalk remaining). In Exp. 2, cows were continuously monitored by a leg-mounted automated activity monitor. Estrous expression was quantified using the relative increase in physical activity at estrus in relation to the days before estrus. Estrous expression was classified as no estrus [<100% relative increase in activity (RI)], weak intensity (100-299% RI), and strong intensity (≥300% RI). Data were analyzed by analysis of variance using mixed linear regression models (GLIMMIX) in SAS (SAS Institute Inc.). A total of 65.2% (914/1,401) and 89.2% (1,019/1,142) of cows from Exp. 1 and Exp. 2, respectively, displayed estrus at the end of the ovulation synchronization protocol. In Exp. 1, cows expressing estrus before to ET had greater pregnancy per ET than those that did not [41.0 ± 2.3% (381/914) vs. 31.5 ± 2.9% (151/487), respectively]. Similarly, in Exp. 2, cows classified in the strong intensity group had greater pregnancy per ET compared with cows in the weak intensity and no estrus groups [41.3 ± 2.2% (213/571) vs. 32.7 ± 2.7% (115/353) vs. 11.3 ± 3.5% (26/218), respectively]. There was no effect of ET type on pregnancy per ET in Exp. 1. However, in Exp. 2, cows that received an in vivo-produced embryo, either fresh or frozen, had greater pregnancy per ET compared with cows that received in vitro-produced embryo. Cows receiving embryos in the early blastocyst and blastocyst stage had greater fertility compared with cows receiving embryos in the morula stage. There was an interaction between the occurrence of estrus and the stage of embryo development on pregnancy per ET, cows which displayed estrus and received a morula or early blastocyst had greater pregnancy per ET than cows that did not display estrus. In conclusion, the occurrence and the intensity of estrous expression improved pregnancy per ET in recipient lactating dairy cows and thus could be used as a tool to assist in the decision making of reproduction strategies in dairy farms.


Asunto(s)
Inseminación Artificial , Condicionamiento Físico Animal , Animales , Bovinos , Transferencia de Embrión/veterinaria , Estro , Sincronización del Estro , Femenino , Inseminación Artificial/veterinaria , Lactancia , Embarazo , Progesterona
12.
Eur Arch Otorhinolaryngol ; 279(12): 5905-5911, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35881191

RESUMEN

PURPOSE: The histological diagnosis after diagnostic thyroidectomy for indeterminate thyroid nodules is often non-malignant and some cancers detected are considered 'indolent'. The safety and effectiveness of conservative management in these patients are unclear. The aim of this study was to determine the safety of conservative management of indeterminate thyroid nodules and to explore association between clinical features and pathology in patients undergoing surgery. METHODS: This is a retrospective cohort study of patients presenting to a single centre over a 4-year period (2013-2016) with thyroid nodules that were considered indeterminate (thy3f in the UK RCPath classification) on cytology. Demographic data, ultrasound features, follow-up details (in those undergoing conservative management) and histology details (in those undergoing surgery) were collected. RESULTS: Of 164 patients that had Thy3f cytology, 34 were initially managed conservatively; however, 4 of these eventually had surgery (due to patient preference). No patient on conservative management had significant disease progression on ultrasound at a median (interquartile range) of 27 (16-40) months. Of the 134 patients that underwent surgery, 26 had thyroid malignancy. The BTA 'U' classification, gender and age (> 55) were not associated with malignancy in these nodules, but larger nodules (> 40 mm) were more likely to be malignant (p = 0.042). CONCLUSIONS: Conservative management of indeterminate (Thy3f or Bethesda stage IV) thyroid nodules is safe in the short term and may be indicated in selected cases after appropriate discussion of risks and benefits of surgery.


Asunto(s)
Neoplasias de la Tiroides , Nódulo Tiroideo , Humanos , Nódulo Tiroideo/diagnóstico por imagen , Nódulo Tiroideo/cirugía , Estudios Retrospectivos , Tratamiento Conservador , Biopsia con Aguja Fina , Neoplasias de la Tiroides/diagnóstico , Neoplasias de la Tiroides/cirugía
13.
J Avian Med Surg ; 36(3): 316-324, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36468810

RESUMEN

A 20-year-old, female, red-lored Amazon parrot (Amazona autumnalis) was presented for a 2-week history of weakness. On physical examination, the bird was quiet, fluffed, weak, and had a distended coelom. Radiographic and ultrasound imaging revealed coelomic distention, increased pulmonary parenchymal opacity, renomegaly, dilated intestines, and a thickened ventricular wall. The results of a complete blood cell count indicated the patient was anemic (28%) and had intermediate to large lymphocytes with immature chromatin that were suspected to be neoplastic. Immunocytochemistry on peripheral blood determined that the suspected circulating neoplastic cells were cluster of differentiation (CD) 3+ and occasionally expressed multiple myeloma oncogene 1 (MUM1). Abnormalities from a plasma biochemistry panel were moderate hyperphosphatemia (6.8 mg/dL), marked hyperproteinemia (13.6 g/L), analbuminemia (0 g/dL), and marked hyperglobulinemia (13.6 g/dL). Agarose gel plasma protein electrophoresis documented the presence of albumin (1.2 g/dL) and monoclonal bands which, on reduced lithium dodecyl sulfate polyacrylamide gel electrophoresis, resolved as 60-kd and ∼25-kd bands consistent with immunoglobulin Y heavy and light chains. On the basis of these findings, multiple myeloma was diagnosed. Because of a poor prognosis, the bird was euthanized for postmortem examination. Bone marrow cytology from samples collected during the postmortem examination revealed 17.4% plasma cells and 24% large immature cells with occasional plasmacytoid features. Histopathologic findings included aggregates of neoplastic plasma cells in the bone marrow, spleen, kidney, liver, gastrointestinal tract, muscle, ovary, and brain. The neoplastic cells were strongly immunoreactive for MUM1 and cluster of differentiation 3 (CD3), but negative for CD79a, paired box protein 5, and CD20. This confirmed the clinical diagnosis of multiple myeloma. This report describes an avian immunoglobulin Y-secreting multiple myeloma with aberrant CD3 expression and pseudoanalbuminemia. Aberrant CD3 expression by avian multiple myeloma may explain previously published cases of birds with a monoclonal gammopathy and apparent T-cell lymphoma diagnosed by CD3 immunoreactivity.


Asunto(s)
Amazona , Mieloma Múltiple , Psittaciformes , Femenino , Animales , Mieloma Múltiple/veterinaria , Riñón , Hígado
14.
Osteoarthritis Cartilage ; 29(1): 134-142, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33227436

RESUMEN

OBJECTIVE: Joint movements sustain cartilage fluid load support (FLS) through a combination of contact migration and periodic bath exposure. Although there have been suggestions that small involuntary movements may disrupt load-induced exudation during prolonged inactivity, theoretical studies have shown otherwise. This work used well-controlled explant measurements to experimentally test an existing hypothesis that the range-of-motion must exceed the contact length to sustain non-zero FLS. METHOD: Smooth glass spheres (1.2-3.2 mm radius) were slid at 1.5 mm/s (Péclet number >100) against bovine osteochondral explants under varying normal loads (0.05-0.1 N) and migration lengths (0.05-7 mm) using a custom instrument. In situ deformation measurements were used to quantify FLS. RESULTS: Non-zero FLS was maintained at migration lengths as small as 0.05 mm or <10% the typical contact diameter. FLS peaked when track lengths exceeded 10 times the contact diameter. For migration lengths below this threshold, FLS decreased with increased contact stress. CONCLUSIONS: Migration lengths far smaller than the contact diameter can sustain non-zero FLS, which, from a clinical perspective, indicates that fidgeting and drifting can mitigate exudation and loss of FLS during prolonged sitting and standing. Nonetheless, FLS decreased monotonically with decreased migration length when migration lengths were less than 10 times the contact diameter. The results demonstrate: (1) potential biomechanical benefits from small movement (e.g., drifting and fidgeting); (2) the quantitative limits of those benefits; (3) and how loads, movement patterns, and mobility likely impact long term FLS.


Asunto(s)
Cartílago Articular/fisiología , Rango del Movimiento Articular/fisiología , Conducta Sedentaria , Líquido Sinovial/fisiología , Soporte de Peso , Animales , Fenómenos Biomecánicos , Bovinos , Presión Hidrostática
15.
Phys Rev Lett ; 127(12): 125001, 2021 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-34597087

RESUMEN

Inertial confinement fusion implosions designed to have minimal fluid motion at peak compression often show significant linear flows in the laboratory, attributable per simulations to percent-level imbalances in the laser drive illumination symmetry. We present experimental results which intentionally varied the mode 1 drive imbalance by up to 4% to test hydrodynamic predictions of flows and the resultant imploded core asymmetries and performance, as measured by a combination of DT neutron spectroscopy and high-resolution x-ray core imaging. Neutron yields decrease by up to 50%, and anisotropic neutron Doppler broadening increases by 20%, in agreement with simulations. Furthermore, a tracer jet from the capsule fill-tube perturbation that is entrained by the hot-spot flow confirms the average flow speeds deduced from neutron spectroscopy.

16.
Phys Rev Lett ; 126(2): 025002, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33512229

RESUMEN

Inertial confinement fusion implosions must achieve high in-flight shell velocity, sufficient energy coupling between the hot spot and imploding shell, and high areal density (ρR=∫ρdr) at stagnation. Asymmetries in ρR degrade the coupling of shell kinetic energy to the hot spot and reduce the confinement of that energy. We present the first evidence that nonuniformity in the ablator shell thickness (∼0.5% of the total thickness) in high-density carbon experiments is a significant cause for observed 3D ρR asymmetries at the National Ignition Facility. These shell-thickness nonuniformities have significantly impacted some recent experiments leading to ρR asymmetries on the order of ∼25% of the average ρR and hot spot velocities of ∼100 km/s. This work reveals the origin of a significant implosion performance degradation in ignition experiments and places stringent new requirements on capsule thickness metrology and symmetry.

17.
BMC Med Res Methodol ; 21(1): 242, 2021 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-34749654

RESUMEN

BACKGROUND: Identifying successful strategies to improve participant retention in longitudinal studies remains a challenge. In this study we evaluated whether non-traditional fieldworker shifts (after hours during the week and weekends) enhanced participant retention when compared to retention during traditional weekday shifts in the HPTN 071 (PopART) population cohort (PC). METHODS: HPTN 071 (PopART) PC participants were recruited and followed up in their homes on an annual basis by research fieldworkers over a 3-4 year period. The average number of successful follow-up visits, where a PC participant was found and retained in the study, was calculated for each of 3 visit schedules (early weekday shift, late weekday shift, and Saturday shift), and standardized to account for variation in fieldwork shift duration. We used one-way univariate analysis of variance (ANOVA) to describe differences in mean-successful visits and 95% confidence intervals between the shift types. RESULTS: Data on 16 651 successful visits were included. Successful visit rates were higher when conducting Saturday visits (14.0; 95% CI: 11.3-16.6) compared to both regular (4.5; 95% CI: 3.7-5.3) and late weekday shifts (5.3; 95% CI: 4.7-5.8) overall and in all subgroup analyses (P<0.001). The successful visit rate was higher amongst women than men were during all shift types (3.2 vs. 1.3, p<0.001). Successful visit rates by shift type did not differ significantly by age, over time, by PC round or by community triplet. CONCLUSION: The number of people living with HIV continues to increase annually. High quality evidence from longitudinal studies remains critical for evaluating HIV prevention and treatment strategies. This study showed a significant benefit on participant retention through introduction of Saturday shifts for home visits and these data can make an important contribution to the emerging body of evidence for improving retention in longitudinal research. TRIAL REGISTRATION: PopART was approved by the Stellenbosch University Health Research Ethics Committees (N12/11/074), London School of Hygiene and Tropical Medicine (6326) ethics committee and the Division of AIDS (DAIDS) (Protocol ID 11865). PopART was registered with ClinicalTrials.gov (registration number NCT01900977 ).


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , Infecciones por VIH , Estudios de Cohortes , Composición Familiar , Femenino , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Humanos , Masculino , Sudáfrica
18.
Occup Med (Lond) ; 2021 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-34415343

RESUMEN

BACKGROUND: Measurement of waist circumference is used to assess abdominal fat and risk of heart disease, type 2 diabetes, cancer and stroke. It is performed in several clinical settings for health promotion and medical assessment purposes, including statutory medical assessments where results may influence decisions on fitness to work. Under the Diving at Work Regulations 1997, working divers must have an annual assessment of their fitness to dive performed by an approved medical examiner of divers (AMED), appointed by the Health and Safety Executive (HSE). The assessment includes measurement of height, weight and waist circumference, the latter used as an indicator of central adiposity and associated health risks. AIMS: To establish the practice of AMEDs in measuring waist circumference of working divers undergoing medical assessment to determine their fitness to dive. METHODS: Ninety-seven AMEDs were sent a questionnaire and asked to describe their current practice in measuring waist circumference. The response rate was 79%. The audit standard used was the consensus document published by the World Health Organization (WHO). RESULTS: Of the 77 responses, 76 were completed sufficiently to allow analysis. When the waist was measured, there was consistency in the diver's level of clothing, stage of breathing and posture for the procedure but variability in the site of measurement. Only 7/76 (9%) respondents carried out waist measurement fully in line with WHO guidance. CONCLUSIONS: The audit has identified that there is a need for guidance for AMEDs on measuring waist circumference in the statutory medical assessment of working divers.

19.
Vet Dermatol ; 32(4): 374-e106, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34121242

RESUMEN

BACKGROUND: Bullous amyloidosis is a rare disease in humans that has not been described in a veterinary species in the peer-reviewed literature. The human disease is characterised by haemorrhagic vesicles and bullae on the skin and mucosae, which form due to amyloid deposition. HYPOTHESIS/OBJECTIVES: To describe the clinical features, laboratory analysis and histopathological features of an unique presentation of bullous disease in a horse. ANIMALS: A 17-year-old thoroughbred mare presented for weight loss and severe oral cavity ulcers. METHODS AND MATERIALS: Investigations involved haematological evaluation, chemistry profiles, gastroscopy and serum protein electrophoresis, and, postmortem, histopathological evaluation, Congo-red staining and transmission electron microscopy (TEM). RESULTS: Haemorrhagic vesicles and bullae occurred on the mucosa of the oral cavity, lips, oesophagus and stomach, and much less the muzzle, face and mucocutaneous areas of the perineum, where scarring was evident. Histopathological evaluation and Congo-red staining confirmed the presence of amyloid deposits in dermis and submucosa, in association with vesicle and bulla formation, consistent with bullous amyloidosis. TEM confirmed amyloid fibril deposition in the dermis and along the basement membrane zone. Clefts occurred in the superficial dermis and submucosa, which explained haemorrhage and scarring. The presence of a polyclonal gammopathy and the rapid abolishment of Congo-red staining with performate pretreatment supported serum amyloid A and secondary amyloidosis. CONCLUSION AND CLINICAL IMPORTANCE: Bullous amyloidosis is a novel disease of the horse and a newly recognised differential for bullous disease, for which the haemorrhagic nature of bullae, scarring and deep secondary ulcers are considered clinical clues to the condition.


Asunto(s)
Amiloidosis , Enfermedades de los Caballos , Amiloide , Amiloidosis/diagnóstico , Amiloidosis/veterinaria , Animales , Vesícula/veterinaria , Femenino , Enfermedades de los Caballos/diagnóstico , Caballos , Membrana Mucosa , Piel
20.
Can Vet J ; 62(2): 160-166, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33542555

RESUMEN

A restricted polyclonal or biclonal gammopathy resulting in bleeding tendencies was diagnosed in a young, neutered male English bulldog with concurrent splenomegaly, anemia, and severe elevations in IgM and, to a lesser degree, IgA immunoglobulins. There was a positive clinical response to treatment with prednisone and chlorambucil. This case bears similarity to a recently published syndrome of polyclonal gammopathy that is not neoplastic in origin in this breed. Key clinical message: The current case describes the management and clinical course of a recently described syndrome of polyclonal gammopathy in English bulldogs.


Gammapathie et coagulopathie progressives chez un jeune bouledogue Anglais. Une gammapathie polyclonale restreinte ou biclonale résultant en une tendance aux saignements fut diagnostiquée chez un jeune bouledogue Anglais mâle castré, avec une splénomégalie concomitante, de l'anémie et une augmentation sévère des immunoglobulines IgM et, à un degré moindre, des IgA. Une réponse clinique positive au traitement avec de la prednisone et du chlorambucil fut notée. Ce cas comporte des similarités avec un syndrome récemment décrit de gammapathie polyclonale qui ne serait pas d'origine néoplasique chez cette espèce.Message clinique clé :Le présent cas décrit la gestion et l'évolution clinique d'un syndrome récemment décrit de gammapathie polyclonale chez les bouledogues Anglais.(Traduit par Dr Serge Messier).


Asunto(s)
Enfermedades de los Perros , Paraproteinemias , Animales , Enfermedades de los Perros/diagnóstico , Enfermedades de los Perros/tratamiento farmacológico , Perros , Hipergammaglobulinemia/veterinaria , Masculino , Paraproteinemias/veterinaria
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