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1.
Phys Rev Lett ; 132(4): 041001, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38335333

RESUMO

With excellent energy resolution and ultralow-level radiogenic backgrounds, the high-purity germanium detectors in the Majorana Demonstrator enable searches for several classes of exotic dark matter (DM) models. In this work, we report new experimental limits on keV-scale sterile neutrino DM via the transition magnetic moment from conversion to active neutrinos ν_{s}→ν_{a}. We report new limits on fermionic dark matter absorption (χ+A→ν+A) and sub-GeV DM-nucleus 3→2 scattering (χ+χ+A→ϕ+A), and new exclusion limits for bosonic dark matter (axionlike particles and dark photons). These searches utilize the (1-100)-keV low-energy region of a 37.5-kg y exposure collected by the Demonstrator between May 2016 and November 2019 using a set of ^{76}Ge-enriched detectors whose surface exposure time was carefully controlled, resulting in extremely low levels of cosmogenic activation.

2.
Phys Rev Lett ; 132(24): 241802, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38949350

RESUMO

A search is presented for baryon number violating interactions in top quark production and decay. The analysis uses data from proton-proton collisions at a center-of-mass energy of 13 TeV, collected with the CMS detector at the LHC with an integrated luminosity of 138 fb^{-1}. Candidate events are selected by requiring two oppositely charged leptons (electrons or muons) and exactly one jet identified as originating from a bottom quark. Multivariate discriminants are used to separate the signal from the background. No significant deviation from the standard model prediction is observed. Upper limits are placed on the strength of baryon number violating couplings. For the first time the production of single top quarks via baryon number violating interactions is studied. This allows the search to set the most stringent constraints to date on the branching fraction of the top quark decay to a lepton, an up-type quark (u or c), and a down-type quark (d, s, or b). The results improve the previous bounds by 3 to 6 orders of magnitude based on the fermion flavor combination of the baryon number violating interactions.

3.
AIDS Behav ; 28(4): 1186-1196, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37505338

RESUMO

Prior to January 2023, women living with HIV (WLWH) in the United States (US) were discouraged from breastfeeding due to the potential risk of mother-to-child HIV transmission through breastfeeding. Lack of breastfeeding decision-making and experience among WLWH may negatively affect maternal mental health. We implemented a quality improvement initiative to screen WLWH for postpartum depression (PPD), evaluate their attitudes toward breastfeeding, and assess their experience with breastfeeding decision-making. We collected quantitative data from WLWH using a voluntary, self-administered 6-item breastfeeding decision-making and experience survey (administered 1 month postpartum) and a 10-item Edinburgh Postnatal Depression Scale (EPDS, negative = 0-9; administered 1 and 4 months postpartum) tool. We conducted descriptive statistics and cross tabulation analysis. We analyzed 106 WLWH (93.4% non-Hispanic Black/African American; mean age 33.1 years; 82.1% HIV RNA < 200 copies/mL). One in five (19.1%) WLWH had a positive baseline EPDS screen, with the mean EPDS scores decreasing from 5.3 ± 5.4 (baseline) to 4.6 ± 4.8 (follow-up). Among 55 WLWH who provided baseline and follow-up EPDS scores, only 3/13 with a positive baseline EPDS screen had resolved depressive symptoms at follow-up. Over one-third (37.7%) of WLWH indicated feeling "sadness" when asked whether lack of breastfeeding negatively affected their feelings or emotions. Over half of WLWH (51.9%) were aware of the US breastfeeding recommendations, but the majority (60.4%) had never discussed breastfeeding options with a medical provider. Improved provider-patient discussions on infant feeding options among WLWH is needed to increase awareness of breastfeeding choices and promote informed, autonomous breastfeeding decision-making among WLWH.


Assuntos
Depressão Pós-Parto , Infecções por HIV , Lactente , Feminino , Humanos , Adulto , Aleitamento Materno , Saúde Mental , Infecções por HIV/psicologia , Transmissão Vertical de Doenças Infecciosas , Período Pós-Parto , Depressão Pós-Parto/diagnóstico , Depressão Pós-Parto/epidemiologia , Depressão Pós-Parto/psicologia
4.
Clin Radiol ; 79(1): e189-e195, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37949801

RESUMO

AIM: To report the authors' experience of bronchial artery embolisation (BAE) in a series of patients to control haemoptysis associated with infected pulmonary artery pseudoaneurysms (PAPs). MATERIALS AND METHODS: All patients who underwent BAE based on computed tomography angiography (CTA) findings indicative of haemoptysis between February 2019 and September 2022 at Xiangyang Central Hospital were identified. Charts of patients with haemoptysis and infectious PAPs were reviewed retrospectively. Data were collected data on age, sex, underlying pathology, source pulmonary artery of the PAP, association with cavitary lesions or consolidation, systemic angiography findings, technical and clinical success, and follow-up. RESULTS: Seventeen PAPs were treated in 16 patients, with a mean age of 60.3 years (range: 37-82 years). The most common underlying cause was tuberculosis (15/16, 93.8%). Imaging by CTA did not identify the source pulmonary artery for 15 (88.2%) PAPs; all were associated with cavitary lesions or consolidation. All PAPs were visualised on systemic angiography. The technical and clinical success rates were both 87.5%. Two patients who experienced a recurrence of haemoptysis during follow-up underwent repeat CTA, which confirmed the elimination of the previous PAP. CONCLUSION: BAE may be a valuable technique to control haemoptysis associated with infectious PAPs that are visualised on systemic angiography. A possible contributing factor is PAPs arising from very small pulmonary arteries.


Assuntos
Falso Aneurisma , Embolização Terapêutica , Humanos , Pessoa de Meia-Idade , Artéria Pulmonar/diagnóstico por imagem , Falso Aneurisma/complicações , Falso Aneurisma/diagnóstico por imagem , Falso Aneurisma/terapia , Estudos Retrospectivos , Hemoptise/diagnóstico por imagem , Hemoptise/etiologia , Hemoptise/terapia , Angiografia/métodos , Artérias Brônquicas/diagnóstico por imagem , Embolização Terapêutica/métodos , Resultado do Tratamento
5.
J Endocrinol Invest ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869778

RESUMO

PURPOSE: To examine the effect of diabetes, duration of diabetes, and blood glucose on speech-, low/mid-, and high-frequency hearing loss. METHODS: In this cross-sectional study, 2821 participants aged 20-87 years in the China National Health Survey were included. Diabetes was defined as valid fasting blood glucose (FBG) of ≥ 7.0 mmol/L, a self-reported history of diabetes or the use of anti-diabetic medications. Speech-(500, 1000, 2000, and 4000 Hz), low/mid- (500, 1000 and 2000 Hz), and high-frequency (4000, 6000, and 8000 Hz) hearing loss was defined as pure tone average of responding frequencies > 20 dB HL in the better ear, respectively. RESULTS: In fully adjusted models, for speech-, low/mid-, and high-frequency hearing loss, compared with no diabetes, those with diabetes (OR[95%CI]: 1.44 [1.12, 1.86], 1.23 [0.94, 1.61], and 1.75 [1.28, 2.41], respectively) and with diabetes for > 5 years duration (OR[95%CI]: 1.63 [1.09, 2.42], and 1.63 [1.12, 2.36], 2.15 [1.25, 3.70], respectively) were at higher risk. High FBG level was associated with a higher risk of speech-, low/ mid-, and high-frequency hearing loss. And there were stronger associations between HL and diabetes, longer duration and higher in "healthier population" (no hypertension, no dyslipidemia and younger age). CONCLUSION: Diabetes, longer duration, and higher FBG level were independently associated with hearing loss for speech-, low/mid- and high-frequency hearing loss, particularly in higher frequency and "healthier population". Paying more attention to hearing loss in those populations could lower the burden of hearing loss.

6.
Sheng Li Xue Bao ; 76(2): 346-352, 2024 Apr 25.
Artigo em Zh | MEDLINE | ID: mdl-38658383

RESUMO

Programmed death-ligand 1 (PD-L1) is important in maintaining central and peripheral immune tolerance in normal tissues, mediating tumor immune escape and keeping the balance between anti- and pro-inflammatory responses. Inflammation plays an important role in inflammatory lung diseases. This article reviews the research progress and potential clinical value of PD-L1 in inflammatory lung diseases, including acute lung injury, chronic obstructive pulmonary disease, asthma and idiopathic pulmonary fibrosis.


Assuntos
Asma , Antígeno B7-H1 , Doença Pulmonar Obstrutiva Crônica , Humanos , Antígeno B7-H1/metabolismo , Antígeno B7-H1/imunologia , Doença Pulmonar Obstrutiva Crônica/imunologia , Asma/imunologia , Lesão Pulmonar Aguda/imunologia , Inflamação/imunologia , Fibrose Pulmonar Idiopática/imunologia , Fibrose Pulmonar Idiopática/metabolismo , Pneumopatias/imunologia , Pneumopatias/metabolismo , Animais
7.
J Radiol Prot ; 44(1)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38232401

RESUMO

This study assesses the efficacy of Generative Pre-Trained Transformers (GPT) published by OpenAI in the specialised domains of radiological protection and health physics. Utilising a set of 1064 surrogate questions designed to mimic a health physics certification exam, we evaluated the models' ability to accurately respond to questions across five knowledge domains. Our results indicated that neither model met the 67% passing threshold, with GPT-3.5 achieving a 45.3% weighted average and GPT-4 attaining 61.7%. Despite GPT-4's significant parameter increase and multimodal capabilities, it demonstrated superior performance in all categories yet still fell short of a passing score. The study's methodology involved a simple, standardised prompting strategy without employing prompt engineering or in-context learning, which are known to potentially enhance performance. The analysis revealed that GPT-3.5 formatted answers more correctly, despite GPT-4's higher overall accuracy. The findings suggest that while GPT-3.5 and GPT-4 show promise in handling domain-specific content, their application in the field of radiological protection should be approached with caution, emphasising the need for human oversight and verification.


Assuntos
Inteligência Artificial , Proteção Radiológica , Humanos , Física Médica , Fontes de Energia Elétrica
8.
J Ment Health ; 33(3): 386-393, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38845178

RESUMO

BACKGROUND: Mental illnesses and mental health challenges have become increasingly pervasive among Chinese university students. However, the utilization rate of mental health services is low among students. AIMS: We aimed to explore Chinese university students' help-seeking behaviors to understand how they deal with mental health challenges and use the results to inform the development of effective mental health promotion initiatives. METHODS: In this study, we conducted 13 focus group interviews with students in six universities in Jinan, China, including 91 (62%) female students and 56 (38%) male students. We drew on the Theory of Planned Behaviors to guide our thematic analysis to gain a contextual understanding of participants' accounts on help-seeking. RESULTS: Our results have depicted the help-seeking patterns of Chinese university students and show that there are four major behaviors which are self-reliance, seeking support from peers and families, seeking professional support, and accessing virtual mental health care. CONCLUSION: Results from this study can be used to inform the development of mental health literacy programming for students in universities that share similar contexts, and the study has also opened up a new space for using qualitative approaches to study mental health needs and access to care in diverse populations.


Assuntos
Comportamento de Busca de Ajuda , Transtornos Mentais , Serviços de Saúde Mental , Estudantes , Humanos , Feminino , Masculino , Estudantes/psicologia , Universidades , Adulto Jovem , China , Transtornos Mentais/terapia , Transtornos Mentais/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Adulto , Grupos Focais , Saúde Mental , Adolescente
9.
Zhonghua Yu Fang Yi Xue Za Zhi ; 58(6): 931-940, 2024 Jun 06.
Artigo em Zh | MEDLINE | ID: mdl-38955744

RESUMO

Furry animal allergens, particularly cat and dog hair and dander, are common allergens in indoor environments, affecting the health of people world widely. Key sensitizing components such as Fel d 1 from cats and Can f 1 from dogs have been extensively studied and identified by the scientific community. Component resolved diagnosis (CRD) technology in modern diagnostic methods provides an accurate way to identify and distinguish these components, which is extremely important for the prevention of furry animal allergies and the formulation of personalized treatment strategies. To enhance the understanding of furry animal component diagnosis and promote the alignment of the Chinese discipline of allergology with international standards, this article interprets and explains the content of the "Molecular Allergology User's Guide 2.0" recently released by the European Academy of Allergy and Clinical Immunology. It focuses on the epidemiological characteristics of furry animal components, the diversity of allergen protein families, and their clinical diagnosis and management.


Assuntos
Alérgenos , Hipersensibilidade , Alérgenos/análise , Animais , Gatos , Hipersensibilidade/diagnóstico , Cães , Pelo Animal
10.
Zhonghua Yu Fang Yi Xue Za Zhi ; 58(8): 1278-1284, 2024 Aug 06.
Artigo em Zh | MEDLINE | ID: mdl-39142900

RESUMO

Food allergy are triggered by an abnormal immune response to specific food components, with milk and eggs being the most common food allergens, especially in children. Food allergy can cause various symptoms such as rashes, difficulty breathing, and digestive issues. Allergen component diagnostics is a technique used to identify specific allergenic proteins, aiding doctors in providing more precise treatment and management recommendations for patients. This article analyzes the latest research developments and clinical significance of milk and egg allergen components based on the " Molecular Allergology User's Guide 2.0 (MAUG 2.0)" issued by the European Academy of Allergy and Clinical Immunology (EAACI), including their applications in clinical diagnosis, treatment, and management. This article aims to enhance healthcare professionals' understanding of milk and egg allergies, offering new perspectives and practical guidelines for research and clinical practice to promote accurate diagnosis and personalized treatment strategies.


Assuntos
Alérgenos , Hipersensibilidade a Ovo , Hipersensibilidade Alimentar , Hipersensibilidade a Leite , Humanos , Alérgenos/análise , Hipersensibilidade a Ovo/diagnóstico , Hipersensibilidade Alimentar/diagnóstico , Hipersensibilidade a Leite/diagnóstico , Ovos , Animais , Leite
11.
Zhonghua Bing Li Xue Za Zhi ; 53(1): 29-33, 2024 Jan 08.
Artigo em Zh | MEDLINE | ID: mdl-38178743

RESUMO

Objective: To investigate the characteristics of gene mutations in angioimmunoblastic T-cell lymphoma (AITL). Methods: Seventy-five AITL cases diagnosed at the Department of Pathology, Ruijin Hospital Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China from June 2021 to June 2023 were included. Their formalin-fixed and paraffin-embedded or fresh tissues were subject to targeted next generation sequencing (NGS). The sequencing data was collected, and the distribution and type of gene mutations were analyzed. Results: 492 potential driver mutations were identified in 74 out of the 84 genes. Targeted sequencing data for the 75 AITL patients showed that the genes with mutation frequencies of ≥10% were TET2 (89.3%), RHOA (57.3%), IDH2 (37.3%), DNMT3A (36.0%), KMT2C (21.3%), PLCG1 (12.0%), and KDM6B (10.7%). There were significant co-occurrence relationships between TET2 and RHOA, TET2 and IDH2, and RHOA and IDH2 gene mutations (P<0.05), respectively, while TET2 and KDM6B gene mutations were mutually exclusive (P<0.05). Conclusions: The study reveals the mutational characteristics of AITL patients using NGS technology, which would provide insights for molecular diagnosis and targeted therapy of AITL.


Assuntos
Linfadenopatia Imunoblástica , Linfoma de Células T , Humanos , Linfoma de Células T/genética , Linfoma de Células T/patologia , China , Linfadenopatia Imunoblástica/diagnóstico , Mutação , Taxa de Mutação , Histona Desmetilases com o Domínio Jumonji/genética
12.
Zhonghua Jie He He Hu Xi Za Zhi ; 47(7): 654-657, 2024 Jul 12.
Artigo em Zh | MEDLINE | ID: mdl-38955751

RESUMO

Here, we reported a case of delayed diagnosis of allergic bronchopulmonary aspergillosis (ABPA) with low serum IgE and normal Aspergillus fumigatus-specific IgE levels. During the course of the disease, the patient (female, 55 years old) had imaging manifestation of mass shadow and significant elevation of carcinoembryonic antigen, leading to suspicion of a lung tumor. Later, transbronchial lung biopsy tissue culture showed Aspergillus fumigatus. Combined with the history, clinical characteristics and imaging, she was diagnosed with allergic bronchopulmonary aspergillosis combined with invasive pulmonary aspergillosis. As the diagnostic criteria for ABPA do not cover all patients with ABPA, in rare cases where immunological evidence is insufficient, a combination of clinical and imaging features is required for early diagnosis and treatment.


Assuntos
Aspergilose Broncopulmonar Alérgica , Aspergillus fumigatus , Imunoglobulina E , Humanos , Aspergilose Broncopulmonar Alérgica/diagnóstico , Feminino , Pessoa de Meia-Idade , Imunoglobulina E/sangue , Aspergillus fumigatus/imunologia
13.
Zhonghua Wai Ke Za Zhi ; 62(10): 973-977, 2024 Aug 26.
Artigo em Zh | MEDLINE | ID: mdl-39183023

RESUMO

Pancreatic cancer patients often have complaints such as upper abdominal pain and obstructive jaundice when seeking diagnosis and treatment. However, acute pancreatitis as a rare initial clinical manifestation of pancreatic cancer is often overlooked in clinical practice. This oversight often leads to a delayed diagnosis of pancreatic cancer, uncertainty in treatment strategies, and significantly affects patients' quality of life and prognosis. Therefore, early diagnosis and treatment, and active follow-up are crucial for patients with acute pancreatitis as an initial symptom of pancreatic cancer. Upon admission to such patients, common causes such as gallstones, alcohol abuse, and hyperlipidemia should be initially ruled out. Evaluation with tumor markers, CT and MRI, and endoscopic ultrasound are essential to confirm the diagnosis of pancreatic cancer. For patients with mild pancreatitis, managing peripancreatic inflammation first before radical resection of pancreatic cancer could reduce postoperative complications. Moreover, pancreatitis serves as a high-risk factor for pancreatic cancer, so it is crucial to closely follow up patients with pancreatitis to detect pancreatic cancer early.

14.
Zhonghua Yan Ke Za Zhi ; 60(2): 127-136, 2024 Feb 11.
Artigo em Zh | MEDLINE | ID: mdl-38296318

RESUMO

Objective: To evaluate the efficacy of 0.05% cyclosporine A eye drops combined with vitamin A palmitate eye gel in the treatment of dry eye associated with meibomian gland dysfunction (MGD). Methods: A single-center, prospective, randomized, parallel controlled trial design was used to include patients diagnosed with MGD-associated dry eye. The patients were randomly divided into three groups and administered with medications binocularly for 12 weeks. The CsA+VA group was given 0.05% cyclosporine A eye drops twice a day and vitamin A palmitate eye gel three times a day. The CsA+HA group was given 0.05% cyclosporine A eye drops twice a day and 0.1% sodium hyaluronate eye drops three times a day. The HA group was given 0.1% sodium hyaluronate eye drops 3 times a day. The OSDI score, tear meniscus height, fluorescein tear break-up time, Schirmer Ⅰ test (without anesthesia), tear film lipid layer thickness, meibomian gland morphology and function examination, and corneal fluorescein sodium staining score were evaluated at baseline, 4, 8, and 12 weeks after the initiation of the treatment, respectively. Results: A total of 120 patients with MGD-related dry eye met the enrollment criteria, but 10 patients were lost to follow-up; 110 patients were finally included for observation, including 36 patients in the CsA+VA group, 38 in the CsA+HA group and 36 in the HA group. The OSDI score, tear meniscus height, fluorescein tear break-up time and meibomian gland secretion of the 3 groups were significantly improved. At the 12th week of the treatment, the differences of the CsA+VA group [25.45±15.11, (0.30±0.13) mm, (3.72±1.40) s, (5.03±2.52) points] and the CsA+HA group [26.98±16.89, (0.27±0.10) mm, (4.34±1.76) s, (5.11±2.39) points] from the HA group [24.57±11.26, (0.24±0.06) mm, (3.18±1.11) s, (9.11±3.34) points] were statistically significant (P<0.05). Compared with the CsA+HA group [(68.39±26.66) nm], the tear film lipid layer thickness in the CsA+VA group [(72.61±23.65) nm] was significantly increased (P<0.05). In the CsA+VA group, the meibomian gland secretion characters and discharge capacity among patients with severe abnormalities [(6.28±2.59) and (5.89±2.77) points at the 12th week of treatment], moderate abnormalities [(4.27±2.02) and (4.64±2.02) points at the 12th week of treatment] and mild abnormalities [(2.80±0.84) and (2.60±0.55) points at the 12th week of treatment] were significantly different (P<0.05). Conclusion: 0.05% cyclosporine A combined with vitamin A palmitate can significantly improve the symptoms and signs of patients with MGD-related dry eye, especially the tear film lipid layer thickness and the meibomian gland secretion characters and discharge capacity in severe cases.


Assuntos
Diterpenos , Síndromes do Olho Seco , Disfunção da Glândula Tarsal , Ésteres de Retinil , Humanos , Ciclosporina/uso terapêutico , Estudos Prospectivos , Ácido Hialurônico , Glândulas Tarsais , Lágrimas , Síndromes do Olho Seco/diagnóstico , Soluções Oftálmicas/uso terapêutico , Lipídeos , Fluoresceínas/uso terapêutico
15.
Osteoarthritis Cartilage ; 31(1): 115-125, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36243308

RESUMO

OBJECTIVES: The KNee OsteoArthritis Prediction (KNOAP2020) challenge was organized to objectively compare methods for the prediction of incident symptomatic radiographic knee osteoarthritis within 78 months on a test set with blinded ground truth. DESIGN: The challenge participants were free to use any available data sources to train their models. A test set of 423 knees from the Prevention of Knee Osteoarthritis in Overweight Females (PROOF) study consisting of magnetic resonance imaging (MRI) and X-ray image data along with clinical risk factors at baseline was made available to all challenge participants. The ground truth outcomes, i.e., which knees developed incident symptomatic radiographic knee osteoarthritis (according to the combined ACR criteria) within 78 months, were not provided to the participants. To assess the performance of the submitted models, we used the area under the receiver operating characteristic curve (ROCAUC) and balanced accuracy (BACC). RESULTS: Seven teams submitted 23 entries in total. A majority of the algorithms were trained on data from the Osteoarthritis Initiative. The model with the highest ROCAUC (0.64 (95% confidence interval (CI): 0.57-0.70)) used deep learning to extract information from X-ray images combined with clinical variables. The model with the highest BACC (0.59 (95% CI: 0.52-0.65)) ensembled three different models that used automatically extracted X-ray and MRI features along with clinical variables. CONCLUSION: The KNOAP2020 challenge established a benchmark for predicting incident symptomatic radiographic knee osteoarthritis. Accurate prediction of incident symptomatic radiographic knee osteoarthritis is a complex and still unsolved problem requiring additional investigation.


Assuntos
Osteoartrite do Joelho , Feminino , Humanos , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/patologia , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/patologia , Raios X , Imageamento por Ressonância Magnética/métodos , Radiografia
16.
Opt Lett ; 48(15): 3877-3880, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37527072

RESUMO

An LED-side-pumped Nd:YAG/Cr4+:YAG passively Q-switched (PQS) laser containing an extracavity optical parametric oscillator (EOPO) is demonstrated. As far as we know, it is the first LED-pumped eye-safe laser. The Nd:YAG pump module is optimized to increase the PQS pulse energy to 24 mJ at 1064 nm. By using a single-pass EOPO design, the output energy of the signal pulse at 1573 nm is 7.44 mJ with a pulse width of 16 ns, the peak power is 434 kW, and the pump-to-signal conversion efficiency is 31%. For double-pass EOPO operation, the pump-to-signal conversion efficiency increases to 45.8%, the output energy of signal pulse is up to 10.98 mJ with a pulse width of 23.5 ns, and the peak power is 459 kW.

17.
Phys Rev Lett ; 130(6): 062501, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36827565

RESUMO

The Majorana Demonstrator searched for neutrinoless double-ß decay (0νßß) of ^{76}Ge using modular arrays of high-purity Ge detectors operated in vacuum cryostats in a low-background shield. The arrays operated with up to 40.4 kg of detectors (27.2 kg enriched to ∼88% in ^{76}Ge). From these measurements, the Demonstrator has accumulated 64.5 kg yr of enriched active exposure. With a world-leading energy resolution of 2.52 keV FWHM at the 2039 keV Q_{ßß} (0.12%), we set a half-life limit of 0νßß in ^{76}Ge at T_{1/2}>8.3×10^{25} yr (90% C.L.). This provides a range of upper limits on m_{ßß} of (113-269) meV (90% C.L.), depending on the choice of nuclear matrix elements.

19.
Phys Rev Lett ; 131(15): 152501, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37897780

RESUMO

^{180m}Ta is a rare nuclear isomer whose decay has never been observed. Its remarkably long lifetime surpasses the half-lives of all other known ß and electron capture decays due to the large K-spin differences and small energy differences between the isomeric and lower-energy states. Detecting its decay presents a significant experimental challenge but could shed light on neutrino-induced nucleosynthesis mechanisms, the nature of dark matter, and K-spin violation. For this study, we repurposed the Majorana Demonstrator, an experimental search for the neutrinoless double-beta decay of ^{76}Ge using an array of high-purity germanium detectors, to search for the decay of ^{180m}Ta. More than 17 kg, the largest amount of tantalum metal ever used for such a search, was installed within the ultralow-background detector array. In this Letter, we present results from the first year of Ta data taking and provide an updated limit for the ^{180m}Ta half-life on the different decay channels. With new limits up to 1.5×10^{19} yr, we improved existing limits by 1-2 orders of magnitude which are the most sensitive searches for a single ß and electron capture decay ever achieved. Over all channels, the decay can be excluded for T_{1/2}<0.29×10^{18} yr.

20.
Scand J Gastroenterol ; 58(4): 380-391, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36269095

RESUMO

BACKGROUND: The lack of effective early diagnostic markers is an obstacle in clinical diagnosis and treatment of hepatocellular carcinoma (HCC). Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is an increasing popular approach for identification of clinically relevant parameters including biomarkers. PATIENTS AND METHODS: 540 subjects, including 274 HCC, 119 liver cirrhosis, 89 hepatitis, and 58 healthy volunteers were enrolled. MALDI-TOF MS was used to select potential novel biomarkers from serum of HCC patients. Its clinical application was evaluated by experiments and clinical data analysis. RESULTS: We identified Thymosin ß4 (Tß4) in serum by MALDI-TOF MS. The expression of Tß4 was detected up-regulating in HCC cells and tissues which enhanced motility of HCC cells. More important, the level of serum Tß4 was significantly elevated in HCC patients. The AUROC showed the optimum diagnostic cut-off was 1063.6 ng/mL, ROC and 95% CI of Tß4 (0.908; 0.880-0.935) were larger than that of serum AFP (0.712; 0.662-0.762; p < 0.001). The sensitivity (91.3% vs 83.1%) and specificity (81.2% vs 20.3%) of serum Tß4 were higher than alpha-fetoprotein (AFP). In AFP-negative HCC, the sensitivity could reach to 80.5%. ROC analysis showed serum Tß4 had a better performance compared with AFP in distinguishing early-stage and small HCC. Tß4 is correlated with TNM stage (p = 0.016) and vascular invasion (p = 0.005). Survival analysis indicated the survival time of Tß4 positive patients was shorter (p < 0.001). Cox analysis suggested Tß4 could be an independent factor for HCC prognosis. CONCLUSION: Tß4 may serve as a novel biomarker for HCC diagnosis and prognosis.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , alfa-Fetoproteínas/análise , Neoplasias Hepáticas/diagnóstico , Biomarcadores Tumorais , Prognóstico
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