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1.
Nature ; 609(7926): 269-275, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36071190

RESUMO

Nuclear fusion is one of the most attractive alternatives to carbon-dependent energy sources1. Harnessing energy from nuclear fusion in a large reactor scale, however, still presents many scientific challenges despite the many years of research and steady advances in magnetic confinement approaches. State-of-the-art magnetic fusion devices cannot yet achieve a sustainable fusion performance, which requires a high temperature above 100 million kelvin and sufficient control of instabilities to ensure steady-state operation on the order of tens of seconds2,3. Here we report experiments at the Korea Superconducting Tokamak Advanced Research4 device producing a plasma fusion regime that satisfies most of the above requirements: thanks to abundant fast ions stabilizing the core plasma turbulence, we generate plasmas at a temperature of 100 million kelvin lasting up to 20 seconds without plasma edge instabilities or impurity accumulation. A low plasma density combined with a moderate input power for operation is key to establishing this regime by preserving a high fraction of fast ions. This regime is rarely subject to disruption and can be sustained reliably even without a sophisticated control, and thus represents a promising path towards commercial fusion reactors.

2.
Clin Radiol ; 79(2): 142-149, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37968227

RESUMO

AIM: To compare the diagnostic test of integrated 2-[18F]-fluoro-2-deoxy-d-glucose positron-emission tomography/computed tomography (FDG PET/CT) with that of magnetic resonance imaging (MRI) for the differentiation of malignant peripheral nerve sheath tumours (MPNSTs) in neurofibromatosis type 1 (NF1) patients. MATERIALS AND METHODS: A systematic search was performed in PubMed and EMBASE (last updated in 30 November 2022). Studies investigating the performance of FDG PET/CT and MRI for differentiation of MPNSTs were eligible for inclusion. Only studies reporting a direct comparison between these imaging methods were considered to establish precise summary estimates in the same setting of patients. RESULTS: The pooled estimate of sensitivity of FDG PET/CT was 0.99 and a pooled specificity of 0.53. The pooled estimate of sensitivity of MRI was 0.85 and a pooled specificity of 0.85. CONCLUSION: Analysis of the available studies indicated that FDG PET/CT and MRI had similar diagnostic performances for differentiation of MPNSTs in patients with NF1; however, either technique can be a complement to the other rather than being used singly.


Assuntos
Neurofibromatose 1 , Neurofibrossarcoma , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neurofibromatose 1/diagnóstico por imagem , Neurofibromatose 1/patologia , Fluordesoxiglucose F18 , Glucose , Tomografia Computadorizada por Raios X/métodos , Sensibilidade e Especificidade , Tomografia por Emissão de Pósitrons/métodos , Imageamento por Ressonância Magnética/métodos , Compostos Radiofarmacêuticos
3.
Phys Rev Lett ; 126(12): 125001, 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33834790

RESUMO

Predictive 3D optimization reveals a novel approach to modify a nonaxisymmetric magnetic perturbation to be entirely harmless for tokamaks, by essentially restoring quasisymmetry in perturbed particle orbits as much as possible. Such a quasisymmetric magnetic perturbation (QSMP) has been designed and successfully tested in the KSTAR and DIII-D tokamaks, demonstrating no performance degradation despite the large overall amplitudes of nonaxisymmetric fields and strong response otherwise expected in the tested plasmas. The results indicate that a quasisymmetric optimization is a robust path of error field correction across the resonant and nonresonant field spectrum in a tokamak, leveraging the prevailing concept of quasisymmetry for general 3D plasma confinement systems such as stellarators. The optimization becomes, in fact, a simple eigenvalue problem to the so-called torque response matrices if a perturbed equilibrium is calculated consistent with nonaxisymmetric neoclassical transport.

4.
J Appl Microbiol ; 128(6): 1624-1633, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31951091

RESUMO

AIMS: To study the association between number and positions of mutations with MICs of fluoroquinolone non-susceptible Haemophilus influenzae. METHODS AND RESULTS: More than 40% of 48 H. influenzae isolated from nursing home residents were not susceptible to fluoroquinolone. Amino acid changes in the quinolone resistance determining regions, and correlation with MICs and inhibition zone diameters were analysed. All isolates with reduced susceptibility to fluoroquinolones (MIC ≥0·125 µg ml-1 ) had at least one mutation in gyrA at position 84 and were resistant to nalidixic acid. Compared to isolates with reduced susceptibility, resistant isolates were associated with mutations in gyrA at positions 88 and 134, and in parC at position 88 (P < 0·001). Inhibition zone diameter for nalidixic acid disk ≥23 mm may detect susceptible isolates. CONCLUSIONS: Reduced susceptibility to fluoroquinolones was associated with mutations at position 84 in gyrA. A further increase in fluoroquinolone MIC was associated with mutations in gyrA at positions 88 and 134, and parC at position 88. SIGNIFICANCE AND IMPACT OF THE STUDY: Due to limited resistant H. influenzae strains, prior studies on association between positions of mutations and fluoroquinolone MICs were inconclusive. The comparison of mutations between isolates with susceptibility, reduced susceptibility and high resistance supported the importance of the present study.


Assuntos
Anti-Infecciosos/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/genética , Fluoroquinolonas/farmacologia , Haemophilus influenzae/efeitos dos fármacos , DNA Girase/genética , DNA Topoisomerase IV/genética , Infecções por Haemophilus/microbiologia , Haemophilus influenzae/genética , Haemophilus influenzae/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana , Mutação , Casas de Saúde , Taiwan
5.
Phys Rev Lett ; 123(9): 095001, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31524439

RESUMO

A small nonaxisymmetric (3D) magnetic field can induce nonambipolar transport of the particle species confined in a tokamak and thus a significant change of plasma rotation. This process can be in a favor of instability control in the region where the tokamak plasma is sufficiently collisional and resistive, as observed in the applications of n=1 resonant magnetic perturbations to the KSTAR tokamak. The plasma rotation can be globally accelerated due to radially drifting electrons and constrained to the electron root, if the radial transport is enhanced by an amplified 3D response. This mechanism is verified by a kinetically self-consistent magnetohydrodynamic modeling for both response and transport, which offers the quantitative explanations on the internal n=1 structure detected by electron-cyclotron-emission imaging and the cocurrent plasma spinning observed in the experiments.

6.
BMC Fam Pract ; 20(1): 139, 2019 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-31630674

RESUMO

BACKGROUND: Postgraduate vocational training in family medicine (FM) is essential for physicians to build capacity and develop quality primary care. Inadequate standards in training and curriculum development can contribute to poor recruitment and retention of doctors in primary care. This study aimed to investigate: 1) the satisfaction level of doctors regarding vocational training in family medicine and associated demographics; and 2) the satisfaction level of doctors regarding their family medicine career and associated factors. METHOD: This is a cross sectional study of all family medicine physicians across all government-funded primary care clinics (GOPCs). The study questionnaire consisted of items from a standardized and validated physician survey named the Physician Worklife Survey (PWS) (Konrad et al., Med Care, 1999). We selected three scales (7 items) relating to global job satisfaction, global career satisfaction and global specialty (family medicine) satisfaction with additional items on training and demographics. All significant variables in bivariate analyses were further examined using stepwise logistic regression. RESULTS: Out of 424 eligible family medicine physicians, 368 physicians successfully completed the questionnaire. The response rate was 86.8%. Most participants were male (52.6%), were aged between 35 and 44 years (55.5%), were FM specialists (42.4%), graduated locally (86.2%), and had postgraduate qualifications. Eighty-two percent (82%) of participants were satisfied with their training. Having autonomy and protected time for training were associated with satisfaction with FM training. Satisfaction with family medicine as a career was correlated with physicians' satisfaction with their current job. Doctors who did not enroll in training (p < 0.001) and physicians who were older (p = 0.023) were significantly less satisfied. Stepwise multivariate regression showed that doctors who subjectively believed their training as "broad and in depth' had higher career satisfaction (p < 0.001). CONCLUSION: Overall, the satisfaction level of physicians on current family medicine training in Hong Kong was high. Having autonomy and protected time for training is associated with higher training satisfaction levels. Perceiving FM training as "broad and in-depth" is associated with higher family medicine career satisfaction.


Assuntos
Medicina de Família e Comunidade/educação , Satisfação no Emprego , Educação Vocacional , Adulto , Estudos Transversais , Feminino , Clínicos Gerais/educação , Clínicos Gerais/psicologia , Clínicos Gerais/estatística & dados numéricos , Hong Kong , Humanos , Masculino , Inquéritos e Questionários
7.
Phys Rev Lett ; 119(20): 205001, 2017 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-29219375

RESUMO

The propagation dynamics of resonant magnetic perturbation fields in KSTAR H-mode plasmas with injection of small edge perturbations produced by a supersonic molecular beam injection is reported for the first time. The results show that the perturbation field first excites a plasma response on the q=3 magnetic surface and then propagates inward to the q=2 surface with a radially averaged propagation velocity of resonant magnetic perturbations field equal to 32.5 m/ s. As a result, the perturbation field brakes the toroidal rotation on the q=3 surface first causing a momentum transport perturbation that propagates both inward and outward. A higher density fluctuation level is observed. The propagation velocity of the resonant magnetic perturbations field is larger than the radial propagation velocity of the perturbation in the toroidal rotation.

8.
Development ; 140(17): 3577-88, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23903188

RESUMO

In contrast to most adult organisms, freshwater planarians can regenerate any injured body part, including their entire nervous system. This allows for the analysis of genes required for both the maintenance and regeneration of specific neural subtypes. In addition, the loss of specific neural subtypes may uncover previously unknown behavioral roles for that neural population in the context of the adult animal. Here we show that two homeodomain transcription factor homologs, Smed-lhx1/5-1 and Smed-pitx, are required for the maintenance and regeneration of serotonergic neurons in planarians. When either lhx1/5-1 or pitx was knocked down by RNA interference, the expression of multiple canonical markers for serotonergic neurons was lost. Surprisingly, the loss of serotonergic function uncovered a role for these neurons in the coordination of motile cilia on the ventral epidermis of planarians that are required for their nonmuscular gliding locomotion. Finally, we show that in addition to its requirement in serotonergic neurons, Smed-pitx is required for proper midline patterning during regeneration, when it is required for the expression of the midline-organizing molecules Smed-slit in the anterior and Smed-wnt1 in the posterior.


Assuntos
Proteínas com Homeodomínio LIM/metabolismo , Fatores de Transcrição Box Pareados/metabolismo , Planárias/fisiologia , Regeneração/fisiologia , Neurônios Serotoninérgicos/fisiologia , Animais , Sequência de Bases , Teorema de Bayes , Biologia Computacional , Sequenciamento de Nucleotídeos em Larga Escala , Hibridização In Situ , Proteínas com Homeodomínio LIM/genética , Funções Verossimilhança , Microscopia de Vídeo , Modelos Genéticos , Dados de Sequência Molecular , Fatores de Transcrição Box Pareados/genética , Filogenia , Interferência de RNA
9.
Genet Mol Res ; 15(1)2016 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-26909914

RESUMO

In this study, we compared the efficiency of simple sequence repeat (SSR) and sequence specific amplified polymorphism (SSAP) markers for analyzing genetic diversity, genetic relationships, and population structure of 87 super sweet corn inbred lines from different origins. SSR markers showed higher average gene diversity and Shannon's information index than SSAP markers. To assess genetic relationships and characterize inbred lines using SSR and SSAP markers, genetic similarity (GS) matrices were constructed. The dendrogram using SSR marker data showed a complex pattern with nine clusters and a GS of 53.0%. For SSAP markers, three clusters were observed with a GS of 50.8%. Results of combined marker data showed six clusters with 53.5% GS. To analyze the genetic population structure of SSR and SSAP marker data, the 87 inbred lines were divided into groups I, II, and admixed based on the membership probability threshold of 0.8. Using combined marker data, the population structure was K = 3 and was divided into groups I, II, III, and admixed. This study represents a comparative analysis of SSR and SSAP marker data for the study of genetic diversity and genetic relationships in super sweet corn inbred lines. Our results would be useful for maize-breeding programs in Korea.


Assuntos
Variação Genética , Genética Populacional , Repetições de Microssatélites , Zea mays/genética , Melhoramento Vegetal , República da Coreia
10.
Hong Kong Med J ; 21(3): 217-23, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25810024

RESUMO

OBJECTIVE: To evaluate the treatment outcomes of enchondroma of the hand with artificial bone substitute versus autologous (iliac) bone graft. DESIGN: Historical cohort study. SETTING: Tertiary referral centre, Hong Kong. PATIENTS: A total of 24 patients with hand enchondroma from January 2001 to December 2013 who underwent operation at the Prince of Wales Hospital and Alice Ho Miu Ling Nethersole Hospital in Hong Kong were reviewed. Thorough curettage of the tumour was performed in all patients, followed by either autologous bone graft impaction under general anaesthesia in 13 patients, or artificial bone substitute in 11 patients (10 procedures were performed under local or regional anaesthesia and 1 was done under general anaesthesia). The functional outcomes and bone incorporation were measured by QuickDASH (shortened version of the Disabilities of the Arm, Shoulder and Hand questionnaire) scores and radiological appearance, respectively. The mean follow-up period was 59 months. RESULTS: There were eight men and 16 women, with a mean age of 40 years. Overall, 17 cases involved phalangeal bones and seven involved metacarpal bones. Among both groups of patients, most of the affected digits had good range of motion and function after surgery. One patient in each study group had complications of local soft tissue inflammation. One patient in the artificial bone substitute group was suspected to have recurrence 8 years after operation. Among the autologous bone graft group, four patients had persistent donor site morbidity at the last follow-up. In all patients, radiographs showed satisfactory bone incorporation. CONCLUSIONS: Artificial bone substitute is a safe and effective treatment option for hand enchondroma, with satisfactory functional and radiographic outcomes. Artificial bone substitute offers the additional benefits of enabling the procedure to be done under local anaesthesia on a day-case basis with minimal complications.


Assuntos
Neoplasias Ósseas/cirurgia , Substitutos Ósseos/uso terapêutico , Transplante Ósseo , Condroma/cirurgia , Mãos/cirurgia , Recidiva Local de Neoplasia/cirurgia , Adulto , Neoplasias Ósseas/diagnóstico por imagem , Transplante Ósseo/efeitos adversos , Condroma/diagnóstico por imagem , Feminino , Mãos/diagnóstico por imagem , Humanos , Ílio/transplante , Masculino , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos , Centros de Atenção Terciária , Sítio Doador de Transplante , Resultado do Tratamento , Adulto Jovem
11.
Eur J Clin Microbiol Infect Dis ; 33(2): 233-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23955154

RESUMO

This study investigated the in vitro susceptibilities of methicillin-resistant Staphylococcus aureus (MRSA) to nine antimicrobial agents in Taiwan. A total of 1,725 isolates were obtained from 20 hospitals throughout Taiwan from 2006 to 2010. The minimum inhibitory concentrations (MICs) of the nine agents were determined by the agar dilution method. The MICs of mupirocin and tyrothricin were determined for 223 MRSA isolates collected from 2009 to 2010. For vancomycin, 99.7 % were susceptible; however, 30.0 % (n = 517) exhibited MICs of 2 µg/ml and 0.3 % (n = 6) demonstrated intermediate susceptibility (MICs of 4 µg/ml). Nearly all isolates (≥ 99.9 %) were susceptible to teicoplanin, linezolid, and daptomycin. The MIC90 values were 2 µg/ml for ceftobiprole and 1 µg/ml for nemonoxacin. The MIC90 values of mupirocin and tyrothricin were 0.12 and 4 µg/ml, respectively. MIC creep was noted for daptomycin during this period, but not for vancomycin, teicoplanin, linezolid, or tigecycline. For isolates with vancomycin MICs of 2 µg/ml, the MIC90 values were 2 µg/ml for teicoplanin, 0.5 µg/ml for daptomycin, and 0.5 µg/ml for tigecycline. Those values were four- to eight-fold higher than those among isolates with vancomycin MICs of 0.5 µg/ml (2, 0.06, and 0.12 µg/ml, respectively). Of the nine MRSA isolates exhibiting non-susceptibility to vancomycin (n = 6), teicoplanin (n = 1), daptomycin (n = 2), or tigecycline (n = 1), all had different pulsotypes, indicating the absence of intra-hospital or inter-hospital spread. The presence of a high proportion of MRSA isolates with elevated MICs (2 µg/ml) and MIC creep of daptomycin might alert clinicians on the therapy for serious MRSA infections in Taiwan.


Assuntos
Antibacterianos/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Cefalosporinas/farmacologia , Monitoramento Epidemiológico , Humanos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Quinolonas/farmacologia , Infecções Estafilocócicas/microbiologia , Taiwan , Tirotricina/farmacologia
12.
Epidemiol Infect ; 142(10): 2180-5, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25116133

RESUMO

This multicentre surveillance study was conducted to investigate the trends in incidence and aetiology of healthcare-associated bloodstream infections (HCA-BSIs) in Taiwan. From 2000 to 2011 a total of 56 830 HCA-BSIs were recorded at three medical centres, and coagulase-negative staphylococci (CoNS) were the most common pathogens isolated (n = 9465, 16·7%), followed by E. coli (n = 7599, 13·4%). The incidence of all HCA-BSIs in each and all hospitals significantly increased over the study period owing to the increase of aerobic Gram-positive cocci and Enterobacteriaceae by 4·2% and 3·6%, respectively. Non-fermenting Gram-negative bacteria, Bacteroides spp. and Candida spp. also showed an increase but there was a significant decline in the numbers of methicillin-resistant S. aureus. In conclusion, the incidence of HCA-BSIs in Taiwan is significantly increasing, especially for Enterobacteriaceae and aerobic Gram-positive cocci.


Assuntos
Bacteriemia/epidemiologia , Infecções por Bacteroides/epidemiologia , Candidíase/epidemiologia , Infecção Hospitalar/epidemiologia , Infecções por Enterobacteriaceae/epidemiologia , Infecções por Escherichia coli/epidemiologia , Infecções Estafilocócicas/epidemiologia , Bacteriemia/microbiologia , Infecções por Bacteroides/microbiologia , Candidíase/microbiologia , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana , Infecções por Enterobacteriaceae/microbiologia , Infecções por Bactérias Gram-Negativas/epidemiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Positivas/epidemiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Incidência , Resistência a Meticilina , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Infecções Estafilocócicas/microbiologia , Taiwan/epidemiologia
13.
J Hosp Infect ; 149: 108-118, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38782057

RESUMO

BACKGROUND: In Taiwan, sequence type (ST) 239 and ST59 were two major clones among meticillin-resistant Staphylococcus aureus (MRSA) clinical isolates in the past two decades. USA300 (ST8) prevailed in the Americas but not in outside areas. Recently USA300 (ST8) emerged and was increasingly identified in Taiwan; we thus conducted an island-wide study to explore the role of USA300 among MRSA isolates. METHODS: One hundred MRSA bloodstream isolates identified in 2020 from each of the six participating hospitals in Taiwan were collected and characterized. The first 10 ST8 isolates from each hospital were further analysed by whole-genome sequencing. RESULTS: Of the 590 confirmed MRSA isolates, a total of 22 pulsotypes and 21 STs were identified. The strain of pulsotype AI/ST8 was the most common lineage identified, accounting for 187 isolates (31.7%) and dominating in five of six hospitals, followed by pulsotype A/ST239 (14.7%), pulsotype C/ST59 (13.9%) and pulsotype D/ST59 (9.2%). Of the 187 pulsotype AI/ST8 isolates, 184 isolates were characterized as USA300 and clustered in three major sub-pulsotypes, accounting for 78%. Ninety per cent of the 60 ST8 isolates for whole-genome sequencing were clustered in three major clades. CONCLUSIONS: In 2020, USA300 became the most common clone of MRSA in Taiwan, accounting for >30% of MRSA bloodstream isolates island wide. Most of USA300 isolates circulating in Taiwan might have been imported on multiple occasions and evolved into at least three successful local clades. MRSA USA300 has successfully established its role in Taiwan, an area outside of the Americas.


Assuntos
Genótipo , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Sequenciamento Completo do Genoma , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/classificação , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Taiwan/epidemiologia , Humanos , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/epidemiologia , Epidemiologia Molecular , Hospitais/estatística & dados numéricos , Bacteriemia/microbiologia , Bacteriemia/epidemiologia , Tipagem Molecular
14.
ESMO Open ; 9(5): 103007, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38744101

RESUMO

BACKGROUND: Understanding stakeholders' perception of cure in prostate cancer (PC) is essential to preparing for effective communication about emerging treatments with curative intent. This study used artificial intelligence (AI) for landscape review and linguistic analysis of definition, context and value of cure among stakeholders in PC. MATERIALS AND METHODS: Subject-matter experts (SMEs) selected cure-related key words using Elicit, a semantic literature search engine, and extracted hits containing the key words from Medline, Sermo and Overton, representing academic researchers, health care providers (HCPs) and policymakers, respectively. NetBase Quid, a social media analytics and natural language processing tool, was used to carry out key word searches in social media (representing the general public). NetBase Quid analysed linguistics of key word-specific hit sets for key word count, geolocation and sentiments. SMEs qualitatively summarised key word-specific insights. Contextual terms frequently occurring with key words were identified and quantified. RESULTS: SMEs identified seven key words applicable to PC (number of acquired hits) across four platforms: Cure (12429), Survivor (6063), Remission (1904), Survivorship (1179), Curative intent (432), No evidence of disease (381) and Complete remission (83). Most commonly used key words were Cure by the general public and HCPs (11815 and 224 hits), Survivorship by academic researchers and Survivor by policymakers (378 hits each). All stakeholders discussed Cure and cure-related key words primarily in early-stage PC and associated them with positive sentiments. All stakeholders defined cure differently but communicated about it in relation to disease measurements (e.g. prostate-specific antigen) or surgery. Stakeholders preferred different terms when discussing cure in PC: Cure (academic researchers), Cure rates (HCPs), Potential cure and Survivor/Survivorship (policymakers) and Cure and Survivor (general public). CONCLUSION: This human-led, AI-assisted large-scale qualitative language-based research revealed that cure was commonly discussed by academic researchers, HCPs, policymakers and the general public, especially in early-stage PC. Stakeholders defined and contextualised cure in their communications differently and associated it with positive value.


Assuntos
Inteligência Artificial , Neoplasias da Próstata , Mídias Sociais , Humanos , Masculino , Neoplasias da Próstata/terapia , Linguística/métodos , Política de Saúde , Percepção , Processamento de Linguagem Natural
15.
Nat Commun ; 15(1): 3990, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38734685

RESUMO

The path of tokamak fusion and International thermonuclear experimental reactor (ITER) is maintaining high-performance plasma to produce sufficient fusion power. This effort is hindered by the transient energy burst arising from the instabilities at the boundary of plasmas. Conventional 3D magnetic perturbations used to suppress these instabilities often degrade fusion performance and increase the risk of other instabilities. This study presents an innovative 3D field optimization approach that leverages machine learning and real-time adaptability to overcome these challenges. Implemented in the DIII-D and KSTAR tokamaks, this method has consistently achieved reactor-relevant core confinement and the highest fusion performance without triggering damaging bursts. This is enabled by advances in the physics understanding of self-organized transport in the plasma edge and machine learning techniques to optimize the 3D field spectrum. The success of automated, real-time adaptive control of such complex systems paves the way for maximizing fusion efficiency in ITER and beyond while minimizing damage to device components.

16.
Tissue Antigens ; 82(4): 259-68, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24461005

RESUMO

The role of major histocompatibility complex (MHC) class I chain-related gene A (MICA), a ligand of NKG2D, has been defined in human diseases by its allele associations with various autoimmune diseases, hematopoietic stem cell transplantation (HSCT) and cancer. This study describes a practical system to develop MICA genotyping by allele-specific primer extension (ASPE) on microarrays. From the results of 20 control primers, strict and reliable cut-off values of more than 30,000 mean fluorescence intensity (MFI) as positive and less than 3000 MFI as negative, were applied to select high-quality specific extension primers. Among 55 allele-specific primers, 44 primers could be initially selected as optimal primer. Through adjusting the length, six primers were improved. The other failed five primers were corrected by refractory modification. MICA genotypes by ASPE on microarrays showed the same results as those by nucleotide sequencing. On the basis of these results, ASPE on microarrays may provide high-throughput genotyping for MICA alleles for population studies, disease-gene associations and HSCT.


Assuntos
Alelos , Técnicas de Genotipagem , Antígenos de Histocompatibilidade Classe I/classificação , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Primers do DNA/química , Genótipo , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Reação em Cadeia da Polimerase/métodos , Polimorfismo Genético
17.
Stem Cells ; 30(8): 1734-45, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22696458

RESUMO

Many long-lived species of animals require the function of adult stem cells throughout their lives. However, the transcriptomes of stem cells in invertebrates and vertebrates have not been compared, and consequently, ancestral regulatory circuits that control stem cell populations remain poorly defined. In this study, we have used data from high-throughput RNA sequencing to compare the transcriptomes of pluripotent adult stem cells from planarians with the transcriptomes of human and mouse pluripotent embryonic stem cells. From a stringently defined set of 4,432 orthologs shared between planarians, mice and humans, we identified 123 conserved genes that are ≥5-fold differentially expressed in stem cells from all three species. Guided by this gene set, we used RNAi screening in adult planarians to discover novel stem cell regulators, which we found to affect the stem cell-associated functions of tissue homeostasis, regeneration, and stem cell maintenance. Examples of genes that disrupted these processes included the orthologs of TBL3, PSD12, TTC27, and RACK1. From these analyses, we concluded that by comparing stem cell transcriptomes from diverse species, it is possible to uncover conserved factors that function in stem cell biology. These results provide insights into which genes comprised the ancestral circuitry underlying the control of stem cell self-renewal and pluripotency.


Assuntos
Células-Tronco Pluripotentes/fisiologia , Animais , Diferenciação Celular/genética , Perfilação da Expressão Gênica , Humanos , Mamíferos , Camundongos , Planárias , Células-Tronco Pluripotentes/citologia
18.
Phys Rev Lett ; 111(9): 095002, 2013 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-24033042

RESUMO

One of the important rotational resonances in nonaxisymmetric neoclassical transport has been experimentally validated in the KSTAR tokamak by applying highly nonresonant n=1 magnetic perturbations to rapidly rotating plasmas. These so-called bounce-harmonic resonances are expected to occur in the presence of magnetic braking perturbations when the toroidal rotation is fast enough to resonate with periodic parallel motions of trapped particles. The predicted and observed resonant peak along with the toroidal rotation implies that the toroidal rotation in tokamaks can be controlled naturally in favorable conditions to stability, using nonaxisymmetric magnetic perturbations.

19.
Eur J Clin Microbiol Infect Dis ; 32(2): 245-51, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22918516

RESUMO

This study investigated the clinical and microbiological characteristics of patients with Aeromonas infections of the biliary tract. Patients with bile cultures positive for Aeromonas species during the period July 2004 to December 2011 were identified from a computerized database of a hospital in Taiwan. Patients with Aeromonas infections of the biliary tract were further identified. During the study period, a total of 1,142 isolates of Aeromonas species were obtained from 750 patients. Of those patients, 91 (12.1 %) had Aeromonas infections of the biliary tract. The annual incidence (episodes per 10,000 patient-days) of biliary tract infections caused by all Aeromonas species was 0.31 in 2007, 0.12 in 2010, and 0.27 in 2011. A. hydrophila was the most common species isolated (n = 41, 45.1 %), followed by A. caviae (n = 30, 33.0 %), A. veronii biovar sobria (n = 15, 16.5 %), and A. veronii biovar veronii (n = 5, 5.5 %). The majority of patients (n = 77, 84.6 %) had polymicrobial infections. Hepatobiliary stones (n = 50, 54.9 %) and hepatobiliary cancer (n = 38, 41.8 %) were the most common underlying diseases, followed by diabetes mellitus (n = 29, 31.9 %) and liver cirrhosis (n = 7, 7.7 %). The in-hospital mortality rate was 8.8 %. Infection-related mortality was associated with underlying immunocompromised condition (p = 0.044) and use of mechanical ventilation (p = 0.004), but was not associated with inappropriate antibiotic usage or concomitant bacteremia (n = 8, 8.8 %). In conclusion, biliary tract infections caused by Aeromonas species are not uncommon and can develop in both immunocompromised and immunocompetent patients; however, patients with underlying hepatobiliary diseases are particularly susceptible to these infections.


Assuntos
Aeromonas/classificação , Aeromonas/isolamento & purificação , Doenças Biliares/epidemiologia , Infecções por Bactérias Gram-Negativas/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Doenças Biliares/microbiologia , Doenças Biliares/patologia , Cálculos/complicações , Coinfecção/epidemiologia , Coinfecção/microbiologia , Coinfecção/patologia , Complicações do Diabetes , Feminino , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/patologia , Humanos , Incidência , Masculino , Análise de Sobrevida , Taiwan/epidemiologia
20.
Eur J Clin Microbiol Infect Dis ; 32(4): 543-7, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23135756

RESUMO

This study investigated the clinical characteristics of patients with skin and soft-tissue infections (SSTIs) due to Aeromonas species. Patients with SSTIs caused by Aeromonas species during the period from January 2009 to December 2011 were identified from a computerized database of a regional hospital in southern Taiwan. The medical records of these patients were retrospectively reviewed. A total of 129 patients with SSTIs due to Aeromonas species were identified. A. hydrophila (n = 77, 59.7 %) was the most common pathogen, followed by A. veronii biovar sobria (n = 22, 17.1 %), A. veronii biovar veronii (n = 20, 15.5 %), A. caviae (n = 9, 7.0 %), and A. schubertii (n = 1, 0.8 %). The most common isolates obtained from patients with polymicrobial infections were Klebsiella species (n = 33), followed by Enterococcus spp. (n = 24), Enterobacter spp. (n = 21), Escherichia coli (n = 17), Staphylococcus spp. (n = 17), Streptococcus spp. (n = 17), and Acinetobacter spp. (n = 15). Liver cirrhosis and concomitant bacteremia were more common among patients with monomicrobial Aeromonas SSTIs than among patients with polymicrobial SSTIs. Nine (7 %) patients required limb amputations. The in-hospital mortality rate was 1.6 %. In conclusion, Aeromonas species should be considered as important causative pathogens of SSTIs, and most infections are polymicrobial. In addition, the clinical presentation differs markedly between patients with monomicrobial and those with polymicrobial Aeromonas SSTIs.


Assuntos
Aeromonas/isolamento & purificação , Infecções por Bactérias Gram-Negativas/epidemiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Dermatopatias Bacterianas/epidemiologia , Dermatopatias Bacterianas/microbiologia , Infecções dos Tecidos Moles/epidemiologia , Infecções dos Tecidos Moles/microbiologia , Adulto , Aeromonas/classificação , Idoso , Idoso de 80 Anos ou mais , Coinfecção/epidemiologia , Coinfecção/microbiologia , Coinfecção/mortalidade , Coinfecção/patologia , Feminino , Infecções por Bactérias Gram-Negativas/mortalidade , Infecções por Bactérias Gram-Negativas/patologia , Hospitais , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Dermatopatias Bacterianas/mortalidade , Dermatopatias Bacterianas/patologia , Infecções dos Tecidos Moles/mortalidade , Infecções dos Tecidos Moles/patologia , Análise de Sobrevida , Taiwan
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