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1.
Nature ; 631(8022): 777-782, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38987600

RESUMEN

Most of the state-of-the-art thermoelectric materials are inorganic semiconductors. Owing to the directional covalent bonding, they usually show limited plasticity at room temperature1,2, for example, with a tensile strain of less than five per cent. Here we discover that single-crystalline Mg3Bi2 shows a room-temperature tensile strain of up to 100 per cent when the tension is applied along the (0001) plane (that is, the ab plane). Such a value is at least one order of magnitude higher than that of traditional thermoelectric materials and outperforms many metals that crystallize in a similar structure. Experimentally, slip bands and dislocations are identified in the deformed Mg3Bi2, indicating the gliding of dislocations as the microscopic mechanism of plastic deformation. Analysis of chemical bonding reveals multiple planes with low slipping barrier energy, suggesting the existence of several slip systems in Mg3Bi2. In addition, continuous dynamic bonding during the slipping process prevents the cleavage of the atomic plane, thus sustaining a large plastic deformation. Importantly, the tellurium-doped single-crystalline Mg3Bi2 shows a power factor of about 55 microwatts per centimetre per kelvin squared and a figure of merit of about 0.65 at room temperature along the ab plane, which outperforms the existing ductile thermoelectric materials3,4.

2.
BMC Genomics ; 25(1): 776, 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39123103

RESUMEN

BACKGROUND: Transcription factors (TFs) of plant-specific SHORT INTERNODES (SHI) family play a significant role in regulating development and metabolism in plants. In Artemisia annua, various TFs from different families have been discovered to regulate the accumulation of artemisinin. However, specific members of the SHI family in A. annua (AaSHIs) have not been identified to regulate the biosynthesis of artemisinin. RESULTS: We found five AaSHI genes (AaSHI1 to AaSHI5) in the A. annua genome. The expression levels of AaSHI1, AaSHI2, AaSHI3 and AaSHI4 genes were higher in trichomes and young leaves, also induced by light and decreased when the plants were subjected to dark treatment. The expression pattern of these four AaSHI genes was consistent with the expression pattern of four structural genes of artemisinin biosynthesis and their specific regulatory factors. Dual-luciferase reporter assays, yeast one-hybrid assays, and transient transformation in A. annua provided the evidence that AaSHI1 could directly bind to the promoters of structural genes AaADS and AaCYP71AV1, and positively regulate their expressions. This study has presented candidate genes, with AaSHI1 in particular, that can be considered for the metabolic engineering of artemisinin biosynthesis in A. annua. CONCLUSIONS: Overall, a genome-wide analysis of the AaSHI TF family of A. annua was conducted. Five AaSHIs were identified in A. annua genome. Among the identified AaSHIs, AaSHI1 was found to be localized to the nucleus and activate the expression of structural genes of artemisinin biosynthesis including AaADS and AaCYP71AV1. These results indicated that AaSHI1 had positive roles in modulating artemisinin biosynthesis, providing candidate genes for obtaining high-quality new A. annua germplasms.


Asunto(s)
Artemisia annua , Artemisininas , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas , Factores de Transcripción , Artemisia annua/genética , Artemisia annua/metabolismo , Artemisininas/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regiones Promotoras Genéticas , Filogenia
3.
Small ; 20(27): e2312145, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38342591

RESUMEN

GeTe-based materials exhibit superior thermoelectric performance, while the development of power generation devices has mainly been limited by the challenge of designing the interface due to the phase transition in GeTe. In this work, via utilizing the low-temperature nano-Ag sintering technique and screening suitable Ti-Al alloys, a reliable interface with excellent connection performance has been realized. The Ti-Al intermetallic compounds effectively inhibit the diffusion process at Ti-34Al/Ge0.9Sb0.1Te interface. Thus, the thickness of the interfacial reaction layer only increases by ≈2.08 µm, and the interfacial electrical contact resistivity remains as low as ≈15.2 µΩ cm2 even after 30 days of isothermal aging at 773 K. A high conversion efficiency of ≈11.3% has been achieved in the GeTe/PbTe module at a hot-side temperature of 773 K and a cold-side temperature of 300 K. More importantly, the module's performance and the reliability of the interface remain consistently stable throughout 50 thermal cycles and long-term aging. This work promotes the application of high-performance GeTe materials for thermoelectric power generation.

4.
Liver Int ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38842441

RESUMEN

BACKGROUND: Glucosamine is a dietary supplement commonly used to support joint health. However, there has been interest in exploring other effects of glucosamine on health outcomes due to its ant-inflammation effect. OBJECTIVE: This study compared the risks of major adverse liver outcomes (MALOs) between regular users and non-users of glucosamine among patients with type 2 diabetes and metabolic dysfunction associated steatotic liver disease (MASLD) using the data from a large prospective cohort study. METHODS: Demographic, anthropometric, laboratory and medication prescription information among 18 753 patients with type 2 diabetes and MASLD was obtained from the UK Biobank. MASLD was identified based on hepatic steatosis defined by fatty liver index ≥60 plus the presence of any clues of metabolic dysregulation and cardio-metabolic risk factors, excluding patients with moderate to severe alcohol consumption. RESULTS: During a mean follow-up of 11.4 years, 826 incident MALOs events were recorded. Patients not regularly using glucosamine compared with patients using glucosamine showed a significantly higher risk of the composite MALOs (HR 1.36, 95% confidence interval [CI] 1.09-1.69) as well as most individual MALOs except for ascites. The multivariable-adjusted HRs of MALOs within 3, 5 and 10 years among non-users of glucosamine compared with regular users were 1.79 (95% CI .69-2.03), 1.88 (95% CI 1.21-2.54) and 1.32 (95% CI 1.05-1.72), respectively. Further subgroup analyses in participants with different baseline characteristics and sensitivity analyses excluding participants who regularly took any other supplements and participants who used self-reports to diagnose diabetes confirmed the findings. CONCLUSIONS: The present study indicated that habitual use of glucosamine was associated with a low risk of individual and composite MALOs among patients with type 2 diabetes and MASLD.

5.
Inorg Chem ; 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38687967

RESUMEN

A P-type Mg3Sb2-based Zintl phase compound has been considered a promising candidate for thermoelectric applications. Alloying, which introduces a high concentration of point defects, is particularly effective in scattering phonons and reducing lattice thermal conductivity. Herein, alloying in p-type Mg2.995Na0.005Sb2 via the introduction of elements like Yb, Eu, Ca, and Ba was realized, and the room-temperature lattice thermal conductivity has been effectively reduced to ∼1.1 W m-1 K-1. To further intensify the phonon scattering, two groups of elements (Eu and Cd, and Yb and Cd) were chosen for heavy alloying at the Mg site, and the lattice thermal conductivity of Mg1.49Eu0.5Cd1Na0.01Sb2 was further reduced to ∼0.45 W m-1 K-1. Eventually, a peak zT as high as ∼1.0 was achieved at 773 K, and the compound outperforms the previously reported p-type Mg3Sb2 compounds.

6.
Plant Cell Rep ; 43(3): 62, 2024 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-38336832

RESUMEN

KEY MESSAGE: Yeast extract-induced oxidative stress in Sorbus aucuparia suspension cells leads to the biosynthesis of various hormones, which activates specific signaling pathways that augments biphenyl phytoalexin production. Pathogen incursions pose a significant threat to crop yield and can have a pronounced effect on agricultural productivity and food security. Biphenyl phytoalexins are a specialized group of secondary metabolites that are mainly biosynthesized by Pyrinae plants as a defense mechanism against various pathogens. Despite previous research demonstrating that biphenyl phytoalexin production increased dramatically in Sorbus aucuparia suspension cells (SASCs) treated with yeast extract (YE), the underlying mechanisms remain poorly understood. To address this gap, we conducted an in-depth, multi-omics analysis of transcriptome, proteome, and metabolite (including biphenyl phytoalexins and phytohormones) dynamics in SASCs exposed to YE. Our results indicated that exposure to YE-induced oxidative stress in SASCs, leading to the biosynthesis of a range of hormones, including jasmonic acid (JA), jasmonic acid isoleucine (JA-ILE), gibberellin A4 (GA4), indole-3-carboxylic acid (ICA), and indole-3-acetic acid (IAA). These hormones activated specific signaling pathways that promoted phenylpropanoid biosynthesis and augmented biphenyl phytoalexin production. Moreover, reactive oxygen species (ROS) generated during this process also acted as signaling molecules, amplifying the phenylpropanoid biosynthesis cascade through activation of the mitogen-activated protein kinase (MAPK) pathway. Key genes involved in these signaling pathways included SaBIS1, SaBIS2, SaBIS3, SaPAL, SaB4H, SaOMT, SaUGT1, SaLOX2, SaPR1, SaCHIB1, SaCHIB2 and SaCHIB3. Collectively, this study provided intensive insights into biphenyl phytoalexin accumulation in YE-treated SASCs, which would inform the development of more efficient disease-resistance strategies in economically significant cultivars.


Asunto(s)
Compuestos de Bifenilo , Ciclopentanos , Oxilipinas , Sesquiterpenos , Sorbus , Fitoalexinas , Sorbus/genética , Sorbus/metabolismo , Multiómica , Estrés Oxidativo , Hormonas/metabolismo , Sesquiterpenos/metabolismo
7.
J Clin Lab Anal ; : e25085, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39132875

RESUMEN

BACKGROUND: This study evaluated the performance of the PCR-HRM assay by comparing it with immunohistochemistry (IHC) for mismatch repair (MMR) proteins and the PCR capillary electrophoresis (PCR-CE) methods. RESULTS: A total of 224 patients with colorectal cancer participated in the study, with nearly half having mismatch repair deficiency (dMMR) tissues and the remainder possessing pMMR tissues. There was a 97.77% concordance between the PCR-HRM assay and IHC, and a 97.56% concordance between PCR-HRM and the PCR-CE assay. In comparison with IHC for dMMR proteins, the PCR-HRM demonstrated a sensitivity of 96.36% and a specificity of 99.12%. When juxtaposed with the PCR-CE assay, its sensitivity was 98.96% and specificity stood at 96.33%. The mutations observed in the microsatellite loci were uniformly distributed across all eight loci. Discrepant outcomes were more frequent in instances of MLH1 and PMS2 deficiency. Furthermore, the germline mutation status of MLH1, MSH2, PMS2, and MSH6 in 62 patients was ascertained using next-generation sequencing. All patients displaying MMR gene pathogenic mutations (N = 14) were identified as MSI-H by PCR-HRM, whereas those with MSS tissues (N = 43) did not exhibit MMR gene pathogenic mutations. Thus, the PCR-HRM method proficiently pinpoints tumors with verified germline MMR mutations, indicative of Lynch syndrome. CONCLUSION: Conclusively, the PCR-HRM assay emerges as a swift and congruent diagnostic tool for microsatellite instability, boasting commendable sensitivity and specificity in colorectal cancer.

8.
Echocardiography ; 41(2): e15781, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38380824

RESUMEN

This case demonstrated intraoperative real-time transesophageal echocardiographic monitoring in minimally invasive small-incision Off-pump ligation of a coronary artery fistula,demonstrating the importance of esophageal echocardiography in surgical monitoring.


Asunto(s)
Fístula Arterio-Arterial , Enfermedad de la Arteria Coronaria , Humanos , Ecocardiografía Transesofágica , Fístula Arterio-Arterial/diagnóstico por imagen , Fístula Arterio-Arterial/cirugía , Arteria Pulmonar/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/cirugía
10.
Artículo en Inglés | MEDLINE | ID: mdl-39038331

RESUMEN

Objective: This study aims to analyze the risk factors associated with sleep disorders in patients suffering from depression and investigate the efficacy of psychological interventions in improving these conditions. Methods: A comparative observational study was conducted and a cohort of 162 patients aged 18 to 68, admitted to outpatient or inpatient departments between October 2022 and August 2023, were included in the study. All patients were diagnosed with depression according to the ICD-10 criteria. The patients were divided into two groups: experimental group 1 received cognitive-behavioral therapy (CBT) psychological intervention, while experimental group 2 received conventional psychological treatment. Various parameters, including Hamilton Depression Rating Scale (Ham-D), Hamilton Anxiety Rating Scale (Ham-A), Social Support Rating Scale (SSRS), marital status, and occupation, were assessed and compared between the groups. Multivariate logistic regression was employed to identify risk factors for sleep disorders in depressed patients. The Pittsburgh Sleep Quality Index (PSQI) was utilized to evaluate sleep quality. Results: Logistic regression analysis revealed that depression severity, anxiety levels, subjective social support, and occupational status were significant risk factors for sleep disorders in depressed patients (P < .05). Following intervention, both groups exhibited a significant decrease in PSQI, SAS, and SDS scores, with experimental group 1 demonstrating significantly lower PSQI scores compared to experimental group 2 (P < .05). Moreover, experimental group 1 displayed significantly lower SAS and SDS scores compared to experimental group 2 (P < .05). Conclusions: The severity of depression, anxiety levels, subjective social support, and occupational status contribute to the risk of sleep disorders in depressed patients. Implementing psychological interventions for depressed patients with sleep disorders can effectively improve sleep quality, alleviate anxiety, and enhance overall psychological well-being. These interventions represent a valuable approach to manage depression and comorbid sleep disorders.

11.
Foodborne Pathog Dis ; 21(4): 228-235, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38112756

RESUMEN

The objective was to determine the prevalence of foodborne pathogens in food in Longnan City, Gansu Province, China. In this research, we conducted tests on baked foods, catering foods, meat, and fruits and vegetables sold in supermarkets, farmers' markets, restaurants, retail stores, street stalls, and school canteens from 2013 to 2022. We analyzed the variety of foodborne pathogens (Salmonella, Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, and diarrheagenic Escherichia coli) in different sites and food types. Once foodborne pathogens were detected in the sample, it was deemed unqualified. The total detection rates of foodborne pathogens were 1.559%, 3.349%, 1.980%, 1.040%, 3.383%, and 1.303% in food from supermarkets, farmers' markets, restaurants, retail stores, street stalls, and school canteens, respectively. No pathogenic bacteria were detected in baked foods. Salmonella, S. aureus, L. monocytogenes, B. cereus, and diarrheagenic E. coli were detected in catering foods, among which B. cereus had the highest detection rate. Salmonella was the most common pathogenic bacteria detected in meat, while the detection rate of pathogenic bacteria in fruits and vegetables was low, with only one positive sample for diarrheagenic E. coli. Among the six sites, street stalls (3.382%) and farmers' markets (3.349%) had higher detection rates of pathogens. In general, the detection rate of pathogens from 2013 to 2022 was not high, but there were also some hidden dangers. Catering food is vulnerable to pathogen contamination, and street stalls and farmers' markets are the main sites of pollution. According to the above findings, the regulatory authorities should continue to strengthen supervision, guarantee food safety through early warning, and reduce the risk of food contamination.


Asunto(s)
Escherichia coli , Listeria monocytogenes , Staphylococcus aureus , Microbiología de Alimentos , Contaminación de Alimentos/análisis , Salmonella , Verduras/microbiología
12.
J Clin Ultrasound ; 52(3): 318-320, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38100183

RESUMEN

This article reports a case of LV outflow obstruction caused by abnormalities of the anterior leaflet connection of the mitral papillary muscle, aiming to highlight the importance of combined multimodal imaging in the differential diagnosis of the etiology of LV outflow obstruction.


Asunto(s)
Cardiomiopatía Hipertrófica , Obstrucción del Flujo de Salida Ventricular Izquierda , Obstrucción del Flujo Ventricular Externo , Humanos , Músculos Papilares/diagnóstico por imagen , Obstrucción del Flujo Ventricular Externo/diagnóstico por imagen , Obstrucción del Flujo Ventricular Externo/etiología , Válvula Mitral/diagnóstico por imagen , Imagen Multimodal/efectos adversos , Cardiomiopatía Hipertrófica/complicaciones
13.
J Perianesth Nurs ; 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38402475

RESUMEN

PURPOSE: Tea and coffee are the most commonly consumed types of drinks, identified with multiple health benefits. However, the association between tea and coffee intake and postsurgical hypothyroidism and hypoparathyroidism (PHypoTP) is still unclear. Therefore, the objective of this study is to explore the effect of tea and coffee intake on the risk of PHypoTP. DESIGN: Two-sample Mendelian randomization (MR). METHODS: The primary approach for MR estimates was the inverse-variance-weighted method. MR-Egger, MR Pleiotropy RESidual Sum and Outlier (PRESSO), weighted median, simple mode, and weighted mode were used to detect pleiotropy and heterogeneity. FINDINGS: We found that green tea intake was causally associated with the decreased risk of PHypoTP (ß = -0.019; 95% confidence interval: -0.038 to -0.001; P = .029). However, there was no significant association between coffee intake and the risk of PHypoTP. No heterogeneity or pleiotropy in these results was detected. CONCLUSIONS: Our findings provide the genetic evidence supporting that green tea intake was a protective factor against PHypoTP. Accordingly, we may suggest that patients after thyroidectomy to add green tea into their habitual diet during nursing education.

14.
Entropy (Basel) ; 26(7)2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-39056931

RESUMEN

Investigating the significant "roles" within financial complex networks and their stability is of great importance for preventing financial risks. On one hand, this paper initially constructs a complex network model of the stock market based on mutual information theory and threshold methods, combined with the closing price returns of stocks. It then analyzes the basic topological characteristics of this network and examines its stability under random and targeted attacks by varying the threshold values. On the other hand, using systemic risk entropy as a metric to quantify the stability of the stock market, this paper validates the impact of the COVID-19 pandemic as a widespread, unexpected event on network stability. The research results indicate that this complex network exhibits small-world characteristics but cannot be strictly classified as a scale-free network. In this network, key roles are played by the industrial sector, media and information services, pharmaceuticals and healthcare, transportation, and utilities. Upon reducing the threshold, the network's resilience to random attacks is correspondingly strengthened. Dynamically, from 2000 to 2022, systemic risk in significant industrial share markets significantly increased. From a static perspective, the period around 2019, affected by the COVID-19 pandemic, experienced the most drastic fluctuations. Compared to the year 2000, systemic risk entropy in 2022 increased nearly sixtyfold, further indicating an increasing instability within this complex network.

19.
Int J Biol Macromol ; 264(Pt 1): 130427, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38428763

RESUMEN

The asymmetric reduction of α, ß-unsaturated compounds conjugated with electron-withdrawing group by ene-reductases (ERs) is a valuable method for the synthesis of enantiopure chiral compounds. This study introduced an ER from Corynebacterium casei (CcER) which was heterologously expressed in Escherichia coli BL21(DE3), and the purified recombinant CcER was characterized for its biocatalytic properties. CcER exhibited the highest specific activity at 40 °C and pH 6.5, and showcased appreciable stability below 40 °C over a pH range of 6.0-7.0. The enzyme displayed high resistance to methanol. CcER accepted NADH or NADPH as a cofactor and exhibited a broad substrate spectrum towards α, ß-unsaturated compounds. It achieved complete conversion of 2-cyclohexen-1-one and good performance for stereoselective reduction of (R)-carvone (conversion 98 %, diastereoselectivity 96 %). This study highlights the robustness and potential of CcER.


Asunto(s)
Corynebacterium , Oxidorreductasas , Oxidorreductasas/metabolismo , NADP/metabolismo , Especificidad por Sustrato
20.
PLoS One ; 19(5): e0300315, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38805430

RESUMEN

The National Sustainable Development Agenda Innovation Demonstration Zones (NSDAIDZs) aim to spearhead green development through scientific and technological innovation, showcasing sustainable development to other regions in China and offering valuable insights for countries worldwide. Taking Chengde City, which is one of the cities in the second batch of NSDAIDZs, as a case study, we examine the quantitative impact of technological innovation on green development. Additionally, it investigates the threshold effect of Research and development investments (R&D investments) on the relationship between technological innovation and green development. The results indicate that: (1) technological innovation has a positive promoting effect on green development, with a 1.01% increase in green development for every one unit increase in technological innovation; (2) The positive effect of technological innovation on green development becomes fully realized only when R&D investments and the upgrading of industrial structure surpass a specific threshold value. We contribute to the existing research on the connection between technological innovation and green development in innovation demonstration zones. It also provides empirical insights to foster a mutually beneficial relationship between R&D investments, industrial structure upgrading, and technological innovation, ultimately maximizing the promoting role of technological innovation in green development.


Asunto(s)
Ciudades , Invenciones , Desarrollo Sostenible , China , Desarrollo Sostenible/tendencias , Conservación de los Recursos Naturales/métodos , Tecnología , Humanos
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