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1.
Nature ; 631(8019): 54-59, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38839966

RESUMO

Introducing the concept of topology has revolutionized materials classification, leading to the discovery of topological insulators and Dirac-Weyl semimetals1-3. One of the most fundamental theories underpinning topological materials is the Su-Schrieffer-Heeger (SSH) model4,5, which was developed in 1979-decades before the recognition of topological insulators-to describe conducting polymers. Distinct from the vast majority of known topological insulators with two and three dimensions1-3, the SSH model predicts a one-dimensional analogue of topological insulators, which hosts topological bound states at the endpoints of a chain4-8. To establish this unique and pivotal state, it is crucial to identify the low-energy excitations stemming from bound states, but this has remained unknown in solids because of the absence of suitable platforms. Here we report unusual electronic states that support the emergent bound states in elemental tellurium, the single helix of which was recently proposed to realize an extended version of the SSH chain9,10. Using spin- and angle-resolved photoemission spectroscopy with a micro-focused beam, we have shown spin-polarized in-gap states confined to the edges of the (0001) surface. Our density functional theory calculations indicate that these states are attributed to the interacting bound states originating from the one-dimensional array of SSH tellurium chains. Helices in solids offer a promising experimental platform for investigating exotic properties associated with the SSH chain and exploring topological phases through dimensionality control.

2.
Nature ; 584(7819): E4, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32690939

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

3.
Nature ; 566(7745): 518-522, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30742073

RESUMO

The major breakthroughs in understanding of topological materials over the past decade were all triggered by the discovery of the Z2-type topological insulator-a type of material that is insulating in its interior but allows electron flow on its surface. In three dimensions, a topological insulator is classified as either 'strong' or 'weak'1,2, and experimental confirmations of the strong topological insulator rapidly followed theoretical predictions3-5. By contrast, the weak topological insulator (WTI) has so far eluded experimental verification, because the topological surface states emerge only on particular side surfaces, which are typically undetectable in real three-dimensional crystals6-10. Here we provide experimental evidence for the WTI state in a bismuth iodide, ß-Bi4I4. Notably, the crystal has naturally cleavable top and side planes-stacked via van der Waals forces-which have long been desirable for the experimental realization of the WTI state11,12. As a definitive signature of this state, we find a quasi-one-dimensional Dirac topological surface state at the side surface (the (100) plane), while the top surface (the (001) plane) is topologically dark with an absence of topological surface states. We also find that a crystal transition from the ß-phase to the α-phase drives a topological phase transition from a nontrivial WTI to a normal insulator at roughly room temperature. The weak topological phase-viewed as quantum spin Hall insulators stacked three-dimensionally13,14-will lay a foundation for technology that benefits from highly directional, dense spin currents that are protected against backscattering.

4.
Ann Oncol ; 35(1): 77-90, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37879444

RESUMO

BACKGROUND: Amivantamab plus carboplatin-pemetrexed (chemotherapy) with and without lazertinib demonstrated antitumor activity in patients with refractory epidermal growth factor receptor (EGFR)-mutated advanced non-small-cell lung cancer (NSCLC) in phase I studies. These combinations were evaluated in a global phase III trial. PATIENTS AND METHODS: A total of 657 patients with EGFR-mutated (exon 19 deletions or L858R) locally advanced or metastatic NSCLC after disease progression on osimertinib were randomized 2 : 2 : 1 to receive amivantamab-lazertinib-chemotherapy, chemotherapy, or amivantamab-chemotherapy. The dual primary endpoints were progression-free survival (PFS) of amivantamab-chemotherapy and amivantamab-lazertinib-chemotherapy versus chemotherapy. During the study, hematologic toxicities observed in the amivantamab-lazertinib-chemotherapy arm necessitated a regimen change to start lazertinib after carboplatin completion. RESULTS: All baseline characteristics were well balanced across the three arms, including by history of brain metastases and prior brain radiation. PFS was significantly longer for amivantamab-chemotherapy and amivantamab-lazertinib-chemotherapy versus chemotherapy [hazard ratio (HR) for disease progression or death 0.48 and 0.44, respectively; P < 0.001 for both; median of 6.3 and 8.3 versus 4.2 months, respectively]. Consistent PFS results were seen by investigator assessment (HR for disease progression or death 0.41 and 0.38 for amivantamab-chemotherapy and amivantamab-lazertinib-chemotherapy, respectively; P < 0.001 for both; median of 8.2 and 8.3 versus 4.2 months, respectively). Objective response rate was significantly higher for amivantamab-chemotherapy and amivantamab-lazertinib-chemotherapy versus chemotherapy (64% and 63% versus 36%, respectively; P < 0.001 for both). Median intracranial PFS was 12.5 and 12.8 versus 8.3 months for amivantamab-chemotherapy and amivantamab-lazertinib-chemotherapy versus chemotherapy (HR for intracranial disease progression or death 0.55 and 0.58, respectively). Predominant adverse events (AEs) in the amivantamab-containing regimens were hematologic, EGFR-, and MET-related toxicities. Amivantamab-chemotherapy had lower rates of hematologic AEs than amivantamab-lazertinib-chemotherapy. CONCLUSIONS: Amivantamab-chemotherapy and amivantamab-lazertinib-chemotherapy improved PFS and intracranial PFS versus chemotherapy in a population with limited options after disease progression on osimertinib. Longer follow-up is needed for the modified amivantamab-lazertinib-chemotherapy regimen.


Assuntos
Acrilamidas , Compostos de Anilina , Anticorpos Biespecíficos , Carcinoma Pulmonar de Células não Pequenas , Indóis , Neoplasias Pulmonares , Morfolinas , Pirazóis , Pirimidinas , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carboplatina/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Progressão da Doença , Receptores ErbB/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação , Inibidores de Proteínas Quinases/uso terapêutico
5.
Phys Rev Lett ; 130(17): 173001, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37172243

RESUMO

To test bound-state quantum electrodynamics (BSQED) in the strong-field regime, we have performed high precision x-ray spectroscopy of the 5g-4f and 5f- 4d transitions (BSQED contribution of 2.4 and 5.2 eV, respectively) of muonic neon atoms in the low-pressure gas phase without bound electrons. Muonic atoms have been recently proposed as an alternative to few-electron high-Z ions for BSQED tests by focusing on circular Rydberg states where nuclear contributions are negligibly small. We determined the 5g_{9/2}- 4f_{7/2} transition energy to be 6297.08±0.04(stat)±0.13(syst) eV using superconducting transition-edge sensor microcalorimeters (5.2-5.5 eV FWHM resolution), which agrees well with the most advanced BSQED theoretical prediction of 6297.26 eV.

6.
Br Poult Sci ; 64(1): 47-55, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36129068

RESUMO

1. This study assessed 1) the effects of Paracoccus carotinifaciens supplementation containing high astaxanthin levels on egg production performance and quality, 2) dynamics of carotenoids levels in the egg yolk and 3) taste of astaxanthin-rich egg yolk.2. Laying hens were fed diets containing different levels of P. carotinifaciens-derived astaxanthin (ASX; 0, 2, 4, 8, or 16 ppm) for 28 d (experiment 1) or a diet containing 16 ppm astaxanthin for 28 d followed by a 0 ppm astaxanthin diet for 28 days (experiment 2).3. Production performance, egg quality and egg yolk carotenoid levels were examined in experiment 1 (Ex1) and the dynamics of egg yolk carotenoid levels and egg yolk taste in experiment 2 (Ex2).4. ASX supplementation did not affect production performance or egg quality. ASX levels in the egg yolk became saturated after seven days of 16 ppm supplementation and decreased to less than one-tenth of the saturated levels seven days after supplementation cessation. Supplementation with 16 ppm ASX for 28 d did not affect egg yolk taste.5. Supplementation resulted in the production of ASX-rich eggs for a brief period without affecting production performance, egg quality or taste. Understanding the time taken for the incorporation of ASX into egg yolks is beneficial for value-added egg production and may help in minimising supplementation costs.


Assuntos
Galinhas , Óvulo , Feminino , Animais , Gema de Ovo , Dieta/veterinária , Carotenoides , Suplementos Nutricionais/análise , Ração Animal/análise , Ovos/análise
7.
Int J Life Cycle Assess ; 28(2): 146-155, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36685326

RESUMO

Goal and theoretical commentary: A number of recent life cycle assessment (LCA) studies have concluded that animal-sourced foods should be restricted-or even avoided-within the human diet due to their relatively high environmental impacts (particularly those from ruminants) compared with other protein-rich foods (mainly protein-rich plant foods). From a nutritional point of view, however, issues such as broad nutrient bioavailability, amino acid balances, digestibility and even non-protein nutrient density (e.g., micronutrients) need to be accounted for before making such recommendations to the global population. This is especially important given the contribution of animal sourced foods to nutrient adequacy in the global South and vulnerable populations of high-income countries (e.g., children, women of reproductive age and elderly). Often, however, LCAs simplify this reality by using 'protein' as a functional unit in their models and basing their analyses on generic nutritional requirements. Even if a 'nutritional functional unit' (nFU) is utilised, it is unlikely to consider the complexities of amino acid composition and subsequent protein accretion. The discussion herein focuses on nutritional LCA (nLCA), particularly on the usefulness of nFUs such as 'protein,' and whether protein quality should be considered when adopting the nutrient as an (n)FU. Further, a novel and informative case study is provided to demonstrate the strengths and weaknesses of protein-quality adjustment. Case study methods: To complement current discussions, we present an exploratory virtual experiment to determine how Digestible Indispensable Amino Acid Scores (DIAAS) might play a role in nLCA development by correcting for amino acid quality and digestibility. DIAAS is a scoring mechanism which considers the limiting indispensable amino acids (IAAs) within an IAA balance of a given food (or meal) and provides a percentage contribution relative to recommended daily intakes for IAA and subsequent protein anabolism; for clarity, we focus only on single food items (4 × animal-based products and 4 × plant-based products) in the current case exemplar. Further, we take beef as a sensitivity analysis example (which we particularly recommend when considering IAA complementarity at the meal-level) to elucidate how various cuts of the same intermediary product could affect the interpretation of nLCA results of the end-product(s). Recommendations: First, we provide a list of suggestions which are intended to (a) assist with deciding whether protein-quality correction is necessary for a specific research question and (b) acknowledge additional uncertainties by providing mitigating opportunities to avoid misinterpretation (or worse, dis-interpretation) of protein-focused nLCA studies. We conclude that as relevant (primary) data availability from supply chain 'gatekeepers' (e.g., international agri-food distributors and processors) becomes more prevalent, detailed consideration of IAA provision of contrasting protein sources needs to be acknowledged-ideally quantitatively with DIAAS being one example-in nLCA studies utilising protein as a nFU. We also contend that future nLCA studies should discuss the complementarity of amino acid balances at the meal-level, as a minimum, rather than the product level when assessing protein metabolic responses of consumers. Additionally, a broader set of nutrients should ideally be included when evaluating "protein-rich foods" which provide nutrients that extend beyond amino acids, which is of particular importance when exploring dietary-level nLCA.

8.
Ann Oncol ; 33(9): 959-967, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35688358

RESUMO

BACKGROUND: Prognosis of advanced gastrointestinal stromal tumors (GIST) refractory to tyrosine kinase inhibitors (TKIs) is poor. This randomized, placebo-controlled, phase III trial evaluated the efficacy and safety of pimitespib, a novel heat shock protein 90 inhibitor, in advanced GIST refractory to standard TKIs. PATIENTS AND METHODS: Patients with histologically confirmed GIST refractory to imatinib, sunitinib, and regorafenib were randomized 2 : 1 to oral pimitespib 160 mg/day or placebo for 5 consecutive days per week in 21-day cycles. Following disease progression by blinded central radiological review (BCRR), cross-over to open-label pimitespib was permitted. The primary endpoint was progression-free survival (PFS) by BCRR in the full analysis set. Secondary endpoints included overall survival (OS) adjusted using the rank-preserving structural failure time (RPSFT) method to reduce the expected confounding impact of cross-over. RESULTS: From 31 October 2018 to 30 April 2020, 86 patients were randomized to pimitespib (n = 58) or placebo (n = 28). Median PFS was 2.8 months [95% confidence interval (CI) 1.6-2.9 months] with pimitespib versus 1.4 months (0.9-1.8 months) with placebo [hazard ratio (HR) 0.51 (95% CI 0.30-0.87); one-sided P = 0.006]. Pimitespib showed an improvement in cross-over-adjusted OS compared with placebo [HR 0.42 (0.21-0.85), one-sided P = 0.007]. Seventeen (60.7%) patients receiving placebo crossed-over to pimitespib; median PFS after cross-over was 2.7 months (95% CI 0.7-4.1 months). The most common (≥30%) treatment-related adverse events (AEs) with pimitespib were diarrhea (74.1%) and decreased appetite (31.0%); the most common (≥10%) grade ≥3 treatment-related AE was diarrhea (13.8%). Treatment-related AEs leading to pimitespib discontinuation occurred in three (5.2%) patients. CONCLUSIONS: Pimitespib significantly improved PFS and cross-over-adjusted OS compared with placebo and had an acceptable safety profile in patients with advanced GIST refractory to standard TKIs.


Assuntos
Antineoplásicos , Tumores do Estroma Gastrointestinal , Antineoplásicos/efeitos adversos , Diarreia/induzido quimicamente , Método Duplo-Cego , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Tumores do Estroma Gastrointestinal/patologia , Humanos , Mesilato de Imatinib/uso terapêutico , Indóis , Pirróis
9.
J Intellect Disabil Res ; 66(4): 323-331, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35040230

RESUMO

BACKGROUND: Some patients with intellectual disabilities (ID) are prescribed antipsychotic drugs for symptomatic treatment of behavioural disorders. Nevertheless, it can still prove difficult to perform dental treatments safely for some patients with ID. In such cases, treatment under intravenous sedation (IVS) is one option. Sedative, hypnotic and α-blocking effects of antipsychotic drugs may cause adverse events, such as severe hypotension, among patients who take antipsychotic drugs regularly. This study aimed to investigate the effects of oral antipsychotic medication on cardiovascular function during IVS. Accordingly, we compared mean blood pressure (MBP) and heart rate (HR) between patients who regularly take antipsychotic drugs and patients who do not. METHODS: Thirty-seven patients with ID were enrolled in this study. All participants were outpatients of Special Care Dentistry of general hospital and received dental treatment under IVS performed with a combination of midazolam and propofol. Eighteen patients regularly took antipsychotics (medication group), and 19 patients were not currently taking antipsychotics (non-medication group). MBP, HR, dose, and effect-site concentration of intravenous sedative medications were measured at three points: 'before IVS', 'at optimal sedation', and 'during dental treatment'. RESULTS: The magnitude of reduction of MBP was significantly smaller in the medication group than in the non-medication group (P < 0.023). However, there were no differences in MBP, HR, dose, and effect-site concentration of midazolam and propofol between groups at any point. CONCLUSION: These results suggest that antipsychotic medication may not have clinically significant adverse effects on cardiovascular fluctuations during dental treatment under IVS for persons with ID.


Assuntos
Antipsicóticos , Deficiência Intelectual , Propofol , Antipsicóticos/farmacologia , Antipsicóticos/uso terapêutico , Sedação Consciente/efeitos adversos , Sedação Consciente/métodos , Assistência Odontológica , Humanos , Hipnóticos e Sedativos/efeitos adversos , Deficiência Intelectual/tratamento farmacológico , Deficiência Intelectual/etiologia , Midazolam/efeitos adversos , Midazolam/farmacologia , Midazolam/uso terapêutico , Propofol/efeitos adversos
10.
Eur J Prosthodont Restor Dent ; 30(4): 262-266, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-35333011

RESUMO

PURPOSE/AIM: To evaluate the effect of different veneering liquids used for modeling on microhardness, fracture toughness and biaxial flexural strength of a glass-veneering ceramic. MATERIAL AND METHODS: The manufacturer recommended modeling liquid (ML), distilled water (DW), isopropyl alcohol (IA), 0.5% (P05), 1% (P1), and 2% (P2) polyethylene glycol solutions were mixed with feldspathic ceramic powder to form disc-shaped samples (n=20, 15 mm × 1.2 mm). After sintering, samples were mirror-polished and subjected to Vickers indentation (n=5) for measurement of microhardness and fracture toughness. The remaining 15 samples from each group were subjected to biaxial flexural strength. Data were subjected to one-way ANOVA and Weibull analysis. RESULTS: The microhardness was affected by veneering liquid (p=0.002): DW promoted higher microhardness values than ML and IA. Fracture toughness (p=0.301) and flexural strength (p=0.930) were not affected by the veneering liquid but Weibull parameters were affected. All groups presented surface pores under high magnification. CONCLUSION: Even though the use of DW led to higher values of surface microhardness than the ML, all obtained values are inside the range of enamel microhardness values reported in the literature. Such parameters may affect antagonist wear and should be reported in clinical trials.


Assuntos
Porcelana Dentária , Facetas Dentárias , Água , Teste de Materiais , Propriedades de Superfície , Maleabilidade , Cerâmica , Zircônio , Análise do Estresse Dentário
11.
Phys Rev Lett ; 127(5): 053001, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34397250

RESUMO

We observed electronic K x rays emitted from muonic iron atoms using superconducting transition-edge sensor microcalorimeters. The energy resolution of 5.2 eV in FWHM allowed us to observe the asymmetric broad profile of the electronic characteristic Kα and Kß x rays together with the hypersatellite K^{h}α x rays around 6 keV. This signature reflects the time-dependent screening of the nuclear charge by the negative muon and the L-shell electrons, accompanied by electron side feeding. Assisted by a simulation, these data clearly reveal the electronic K- and L-shell hole production and their temporal evolution on the 10-20 fs scale during the muon cascade process.

12.
Gastric Cancer ; 24(2): 535-543, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33118118

RESUMO

BACKGROUND: The appropriate surgical procedure for patients with upper third early gastric cancer is controversial. We compared total gastrectomy (TG) with proximal gastrectomy (PG) in this patient population. METHODS: A multicenter, non-randomized trial was conducted, with patients treated with PG or TG. We compared short- and long-term outcomes between these procedures. RESULTS: Between 2009 and 2014, we enrolled 254 patients from 22 institutions; data from 252 were included in the analysis. These 252 patients were assigned to either the PG (n = 159) or TG (n = 93) group. Percentage of body weight loss (%BWL) at 1 year after surgery, i.e., the primary endpoint, in the PG group was significantly less than that of the TG group (- 12.8% versus - 16.9%; p = 0.0001). For short-term outcomes, operation time was significantly shorter for PG than TG (252 min versus 303 min; p < 0.0001), but there were no group-dependent differences in blood loss and postoperative complications. For long-term outcomes, incidence of reflux esophagitis in the PG group was significantly higher than that of the TG group (14.5% versus 5.4%; p = 0.02), while there were no differences in the incidence of anastomotic stenosis between the two (5.7% versus 5.4%; p = 0.92). Overall patient survival rates were similar between the two groups (3-year survival rates: 96% versus 92% in the PG and TG groups, respectively; p = 0.49). CONCLUSIONS: Patients who underwent PG were better able to control weight loss without worsening the prognosis, relative to those in the TG group. Optimization of a reconstruction method to reduce reflux in PG patients will be important.


Assuntos
Gastrectomia/métodos , Neoplasias Gástricas/cirurgia , Estômago/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anastomose Cirúrgica , Feminino , Gastrectomia/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Duração da Cirurgia , Prognóstico , Estudos Prospectivos , Estômago/patologia , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Taxa de Sobrevida , Resultado do Tratamento , Redução de Peso
13.
Tech Coloproctol ; 25(12): 1281-1289, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34633567

RESUMO

BACKGROUND: The aim of this study was to assess the long-term annual functional results and quality of life (QOL) after laparoscopic ventral rectopexy (LVR) for rectoanal intussusception (RAI) and/or rectocele. METHODS: This study was a retrospective analysis of prospectively collected data. The study was conducted on patients who underwent LVR for RAI and/or rectocele at our institution between February 2012 and July 2015. The Fecal Incontinence Severity Index (FISI), Constipation Scoring System (CSS), and QOL instruments (i.e., 36-item Short-form Health Survey [SF-36], Patient Assessment of Constipation-QOL [PAC-QOL] scale, and Fecal Incontinence-QOL [FIQL]) were administered before and annually after surgery. The sustainability of substantial symptom improvement (reduction of at least 50% in CSS or FISI scores) postoperatively was evaluated. RESULTS: Fifty-one patients (median age 76 [range 60-93] years, 48 women [94%]) were analyzed. No mortality or major morbidity occurred. After a median follow-up of 60 months (range 12-84 months), no mesh-related complications occurred. The median CSS and FISI scores were significantly reduced at 1 year and remained significantly reduced for 7 years. In patients who reported symptom scores ≥ 3 times postoperatively, sustained improvement of constipation and fecal incontinence was found in about 50% (18/38) and 75% (26/35) of relevant patients, respectively. All PAC-QOL and FIQL scales significantly improved over time for 5 years. Of the SF-36 scales, four showed significant improvement at 1 year but none was significantly improved after 3 years, except for the social functioning scale. CONCLUSIONS: LVR for RAI and/or rectocele was associated with low morbidity and long-term improvement in symptom-specific QOL. The sustainability of postoperative improvement in fecal incontinence was satisfactory, and that in constipation was fair.


Assuntos
Incontinência Fecal , Intussuscepção , Laparoscopia , Prolapso Retal , Idoso , Idoso de 80 Anos ou mais , Constipação Intestinal/etiologia , Constipação Intestinal/cirurgia , Incontinência Fecal/etiologia , Incontinência Fecal/cirurgia , Feminino , Humanos , Intussuscepção/cirurgia , Pessoa de Meia-Idade , Qualidade de Vida , Prolapso Retal/cirurgia , Retocele/complicações , Retocele/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
14.
Osteoarthritis Cartilage ; 28(9): 1235-1244, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32278071

RESUMO

OBJECTIVE: Evaluate articular cartilage by magnetic resonance imaging (MRI) T2∗ mapping within the distal femur and proximal tibia in adolescents with juvenile osteochondritis dissecans (JOCD). DESIGN: JOCD imaging studies acquired between August 2011 and February 2019 with clinical and T2∗ mapping MRI knee images were retrospectively collected and analyzed for 31 participants (9F/22M, 15.0 ± 3.8 years old) with JOCD lesions in the medial femoral condyle (MFC). In total, N = 32 knees with JOCD lesions and N = 14 control knees were assessed. Mean T2∗ values in four articular cartilage regions-of-interest (MFC, lateral femoral condyle (LFC), medial tibia (MT), and lateral tibia (LT)) and lesion volume were measured and analyzed using Wilcoxon-rank-sum tests and Spearman correlation coefficients (R). RESULTS: Mean ± standard error T2∗ differences observed between the lesion-sided MFC and the LFC in JOCD-affected knees (28.5 ± 0.9 95% confidence interval [26.8, 30.3] vs 26.3 ± 0.7 [24.8, 27.7] ms, P = 0.088) and between the affected- and control-knee MFC (28.5 ± 0.9 [26.8, 30.3] vs 28.5 ± 0.6 [27.1, 29.9] ms, P = 0.719) were nonsignificant. T2∗ was significantly increased in the lesion-sided MT vs the LT for the JOCD-affected knees (21.5 ± 0.7 [20.1, 22.9] vs 18.0 ± 0.7 [16.5, 19.5] ms, P = 0.002), but this same difference was also observed between the MT and LT in control knees (21.0 ± 0.6 [19.7, 22.3] vs 18.1 ± 1.1 [15.8, 20.4] ms, P = 0.037). There was no significant T2∗ difference between the affected- and control-knee MT (21.5 ± 0.7 [20.1, 22.9] vs 21.0 ± 0.6 [19.7, 22.3] ms, P = 0.905). T2∗ within the lesion-sided MFC was not correlated with patient age (R = 0.20, P = 0.28) or lesion volume (R = 0.06, P = 0.75). T2∗ values were slightly increased near lesions in later-stage JOCD subjects but without statistical significance. CONCLUSIONS: T2∗ relaxations times were not significantly different from control sites in the articular cartilage overlying JOCD lesions in the MFC or adjacent MT cartilage in early-stage JOCD.


Assuntos
Cartilagem Articular/diagnóstico por imagem , Articulação do Joelho/diagnóstico por imagem , Osteocondrite Dissecante/diagnóstico por imagem , Adolescente , Idade de Início , Criança , Feminino , Fêmur/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Estudos Retrospectivos , Tíbia/diagnóstico por imagem , Adulto Jovem
15.
Phys Rev Lett ; 125(11): 111103, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32975983

RESUMO

To understand the nature of the brightest γ-ray binary system LS 5039, hard x-ray data of the object, taken with the Suzaku and NuSTAR observatories in 2007 and 2016, respectively, were analyzed. The two data sets jointly gave tentative evidence for a hard x-ray periodicity, with a period of ∼9 s and a period increase rate by ∼3×10^{-10} s s^{-1}. Therefore, the compact object in LS 5039 is inferred to be a rotating neutron star, rather than a black hole. Furthermore, several lines of arguments suggest that this object has a magnetic field of several times ∼10^{10} T, two orders of magnitude higher than those of typical neutron stars. The object is hence suggested to be a magnetar, which would be the first to be found in a binary. The results also suggest that the highly efficient particle acceleration process, known to be operating in LS 5039, emerges through interactions between dense stellar winds from the massive primary star, and ultrastrong magnetic fields of the magnetar.

16.
Phys Rev Lett ; 124(13): 136404, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32302163

RESUMO

The chiral crystal is characterized by a lack of mirror symmetry and inversion center, resulting in the inequivalent right- and left-handed structures. In the noncentrosymmetric crystal structure, the spin and momentum of electrons are expected to be locked in the reciprocal space with the help of the spin-orbit interaction. To reveal the spin textures of chiral crystals, we investigate the spin and electronic structure in a p-type semiconductor, elemental tellurium, with the simplest chiral structure by using spin- and angle-resolved photoemission spectroscopy. Our data demonstrate that the highest valence band crossing the Fermi level has a spin component parallel to the electron momentum around the Brillouin zone corners. Significantly, we have also confirmed that the spin polarization is reversed in the crystal with the opposite chirality. The results indicate that the spin textures of the right- and left-handed chiral crystals are hedgehoglike, leading to unconventional magnetoelectric effects and nonreciprocal phenomena.

17.
Colorectal Dis ; 22(2): 178-186, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31454453

RESUMO

AIM: This study aimed to assess the functional outcome of transanal repair of rectocele using patient symptom scores and quality of life (QOL) instruments. METHOD: Patients who underwent transanal repair for symptomatic rectocele between February 2012 and August 2017 were included. This study was a retrospective analysis of prospectively collected data. A standard questionnaire including the Constipation Scoring System (CSS), the Fecal Incontinence Severity Index (FISI) and QOL instruments [Patient Assessment of Constipation (PAC)-QOL, Fecal Incontinence QOL Scale, Short-Form 36 Health Survey (SF-36)] was administered before and after the operation. Physiological assessment and proctography were performed before and after the operation. RESULTS: Thirty patients were included. The median follow-up was 36 (6-72) months. Postoperative proctography showed a reduction in rectocele size [34 mm (14-52 mm) vs 10 mm (0-28 mm), P < 0.0001]. Physiological assessment showed no significant postoperative changes. Constipation was improved in 15/21 patients (71%) at 1 year and 14/20 patients (70%) at the mid-term follow-up. The CSS score reduced at 3 months [12 (8-12) vs 6 (1-12), P < 0.0001] and remained significantly reduced over time until the mid-term follow-up. Faecal incontinence was improved in two-thirds patients at 1 year. Four patients developed new-onset faecal incontinence. All the PAC-QOL scale scores significantly improved over time until 1 year, while two of the eight SF-36 scale scores showed significant postoperative improvement. CONCLUSION: Transanal repair for rectocele improves constipation and constipation-specific QOL.


Assuntos
Constipação Intestinal/fisiopatologia , Incontinência Fecal/fisiopatologia , Complicações Pós-Operatórias/fisiopatologia , Qualidade de Vida , Retocele/cirurgia , Cirurgia Endoscópica Transanal/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Constipação Intestinal/etiologia , Incontinência Fecal/etiologia , Feminino , Humanos , Pessoa de Meia-Idade , Diafragma da Pelve/fisiopatologia , Complicações Pós-Operatórias/etiologia , Estudos Prospectivos , Retocele/fisiopatologia , Reto/fisiopatologia , Estudos Retrospectivos , Índice de Gravidade de Doença , Inquéritos e Questionários , Cirurgia Endoscópica Transanal/métodos , Resultado do Tratamento
18.
Agric Ecosyst Environ ; 300: 106978, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32943807

RESUMO

Pasture-based livestock farming contributes considerably to global emissions of nitrous oxide (N2O), a powerful greenhouse gas approximately 265 times more potent than carbon dioxide. Traditionally, the estimation of N2O emissions from grasslands is carried out by means of plot-scale experiments, where externally sourced animal excreta are applied to soils to simulate grazing conditions. This approach, however, fails to account for the impact of different sward types on the composition of excreta and thus the functionality of soil microbiomes, creating unrealistic situations that are seldom observed under commercial agriculture. Using three farming systems under contrasting pasture management strategies at the North Wyke Farm Platform, an instrumented ruminant grazing trial in Devon, UK, this study measured N2O emissions from soils treated with cattle urine and dung collected within each system as well as standard synthetic urine shared across all systems, and compared these values against those from two forms of controls with and without inorganic nitrogen fertiliser applications. Soil microbial activity was regularly monitored through gene abundance to evaluate interactions between sward types, soil amendments, soil microbiomes and, ultimately, N2O production. Across all systems, N2O emissions attributable to cattle urine and standard synthetic urine were found to be inconsistent with one another due to discrepancy in nitrogen content. Despite previous findings that grasses with elevated levels of water-soluble carbohydrates tend to generate lower levels of N2O, the soil under high sugar grass monoculture in this study recorded higher emissions when receiving excreta from cattle fed the same grass. Combined together, our results demonstrate the importance of evaluating environmental impacts of agriculture at a system scale, so that the feedback mechanisms linking soil, pasture, animals and microbiomes are appropriately considered.

19.
Adv Gerontol ; 33(3): 595-599, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33280348

RESUMO

This study examined the effects of the time of conducting a combined physical and cognitive exercise program on cognitive functions and the mood of older adults. We randomly assigned 17 participants (8 men, 9 women, age 73,24±3,75) to the morning group (AM Group), 18 (8 men, 10 women, age 73,11±4,84) to the afternoon group (PM Group), and they completed a 12-week, dual-task exercise program in the morning or the afternoon, respectively. Moreover, the waiting-list control group consisted of 12 participants (6 men, 6 women, age 73,25±5,93). The cognitive functions and the mood of the participants were assessed before and after the program by using the Neurobehavioral Cognitive Status Examination, and the short version of the Profile of Mood States, respectively. As a result, the exercise program conducted in the afternoon had broader effects on cognitive functions (increased Repetition and Memory) than in the morning (increased Repetition), or the waiting-list control group (increased Judgment). Moreover, the program in the afternoon tended to reduce Anger-Hostility, and Fatigue. In conclusion, conducting the exercise program in the afternoon might be more effective for improving cognitive functions and the mood of older adults than in the morning. However, there was heterogeneity between the groups despite the randomization. Therefore, we suggest conducting a more rigorously controlled study using a larger sample to validate these findings.


Assuntos
Cognição , Exercício Físico , Afeto , Idoso , Terapia por Exercício , Feminino , Humanos , Masculino , Tempo
20.
Phys Rev Lett ; 122(1): 014802, 2019 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-31012720

RESUMO

A novel approach is proposed to demonstrate the two-photon Breit-Wheeler process by using collimated and wide-bandwidth γ-ray pulses driven by 10-PW lasers. Theoretical calculations suggest that more than 3.2×10^{8} electron-positron pairs with a divergence angle of 7° can be created per shot, and the signal-to-noise ratio is higher than 10^{3}. The positron signal, which is roughly 100 times higher than the detection limit, can be measured by using the existing spectrometers. This approach, which could demonstrate the e^{-}e^{+} pair creation process from two photons, would provide important tests for two-photon physics and other fundamental physical theories.

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