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1.
Nature ; 580(7803): 350-354, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32296190

RESUMO

Quantum computers are expected to outperform conventional computers in several important applications, from molecular simulation to search algorithms, once they can be scaled up to large numbers-typically millions-of quantum bits (qubits)1-3. For most solid-state qubit technologies-for example, those using superconducting circuits or semiconductor spins-scaling poses a considerable challenge because every additional qubit increases the heat generated, whereas the cooling power of dilution refrigerators is severely limited at their operating temperature (less than 100 millikelvin)4-6. Here we demonstrate the operation of a scalable silicon quantum processor unit cell comprising two qubits confined to quantum dots at about 1.5 kelvin. We achieve this by isolating the quantum dots from the electron reservoir, and then initializing and reading the qubits solely via tunnelling of electrons between the two quantum dots7-9. We coherently control the qubits using electrically driven spin resonance10,11 in isotopically enriched silicon12 28Si, attaining single-qubit gate fidelities of 98.6 per cent and a coherence time of 2 microseconds during 'hot' operation, comparable to those of spin qubits in natural silicon at millikelvin temperatures13-16. Furthermore, we show that the unit cell can be operated at magnetic fields as low as 0.1 tesla, corresponding to a qubit control frequency of 3.5 gigahertz, where the qubit energy is well below the thermal energy. The unit cell constitutes the core building block of a full-scale silicon quantum computer and satisfies layout constraints required by error-correction architectures8,17. Our work indicates that a spin-based quantum computer could be operated at increased temperatures in a simple pumped 4He system (which provides cooling power orders of magnitude higher than that of dilution refrigerators), thus potentially enabling the integration of classical control electronics with the qubit array18,19.

2.
Brief Bioinform ; 24(5)2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37738400

RESUMO

Implementing a specific cloud resource to analyze extensive genomic data on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) poses a challenge when resources are limited. To overcome this, we repurposed a cloud platform initially designed for use in research on cancer genomics (https://cgc.sbgenomics.com) to enable its use in research on SARS-CoV-2 to build Cloud Workflow for Viral and Variant Identification (COWID). COWID is a workflow based on the Common Workflow Language that realizes the full potential of sequencing technology for use in reliable SARS-CoV-2 identification and leverages cloud computing to achieve efficient parallelization. COWID outperformed other contemporary methods for identification by offering scalable identification and reliable variant findings with no false-positive results. COWID typically processed each sample of raw sequencing data within 5 min at a cost of only US$0.01. The COWID source code is publicly available (https://github.com/hendrick0403/COWID) and can be accessed on any computer with Internet access. COWID is designed to be user-friendly; it can be implemented without prior programming knowledge. Therefore, COWID is a time-efficient tool that can be used during a pandemic.


Assuntos
COVID-19 , Humanos , COVID-19/diagnóstico , Computação em Nuvem , SARS-CoV-2/genética , Fluxo de Trabalho , Genômica
3.
Nature ; 569(7757): 532-536, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31086337

RESUMO

Universal quantum computation will require qubit technology based on a scalable platform1, together with quantum error correction protocols that place strict limits on the maximum infidelities for one- and two-qubit gate operations2,3. Although various qubit systems have shown high fidelities at the one-qubit level4-10, the only solid-state qubits manufactured using standard lithographic techniques that have demonstrated two-qubit fidelities near the fault-tolerance threshold6 have been in superconductor systems. Silicon-based quantum dot qubits are also amenable to large-scale fabrication and can achieve high single-qubit gate fidelities (exceeding 99.9 per cent) using isotopically enriched silicon11,12. Two-qubit gates have now been demonstrated in a number of systems13-15, but as yet an accurate assessment of their fidelities using Clifford-based randomized benchmarking, which uses sequences of randomly chosen gates to measure the error, has not been achieved. Here, for qubits encoded on the electron spin states of gate-defined quantum dots, we demonstrate Bell state tomography with fidelities ranging from 80 to 89 per cent, and two-qubit randomized benchmarking with an average Clifford gate fidelity of 94.7 per cent and an average controlled-rotation fidelity of 98 per cent. These fidelities are found to be limited by the relatively long gate times used here compared with the decoherence times of the qubits. Silicon qubit designs employing fast gate operations with high Rabi frequencies16,17, together with advanced pulsing techniques18, should therefore enable much higher fidelities in the near future.

4.
Phys Rev Lett ; 132(7): 072502, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38427897

RESUMO

Using the fusion-evaporation reaction ^{106}Cd(^{58}Ni,4n)^{160}Os and the gas-filled recoil separator SHANS, two new isotopes _{76}^{160}Os and _{74}^{156}W have been identified. The α decay of ^{160}Os, measured with an α-particle energy of 7080(26) keV and a half-life of 201_{-37}^{+58} µs, is assigned to originate from the ground state. The daughter nucleus ^{156}W is a ß^{+} emitter with a half-life of 291_{-61}^{+86} ms. The newly measured α-decay data allow us to derive α-decay reduced widths (δ^{2}) for the N=84 isotones up to osmium (Z=76), which are found to decrease with increasing atomic number above Z=68. The reduction of δ^{2} is interpreted as evidence for the strengthening of the N=82 shell closure toward the proton drip line, supported by the increase of the neutron-shell gaps predicted in theoretical models.

5.
Clin Radiol ; 79(3): e424-e431, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38101997

RESUMO

AIM: To test the feasibility and performance of dual-energy computed tomography (DECT) in foot arteriography of diabetic patients, where contrast medium is largely reduced within the small vessels. MATERIALS AND METHODS: A total of 50 diabetic patients were enrolled prospectively, where DECT was acquired immediately after the CT angiography (CTA, group A) of the lower extremity. Two images were derived from the DECT data, one optimal virtual monochromatic image (VMI, group B) and one fusion image (group C), both of which were compared against the CTA image for visualising the foot arteries. The contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR) were evaluated. The arterial course and contrast were graded each using a five-point scale. The clarity of small vessel depiction was quantified by comparing the number of plantar metatarsal arteries found in the maximum intensity projection image. RESULTS: The median CNRs and SNRs obtained in group B were approximately 45% and 20% higher than those in groups A and C, respectively (p<0.05). Group B also received higher subjective scores on the posterior tibial artery and the foot arteries (all >3) than groups A and C. The number of visible branches of the plantar metatarsal arteries was found to be substantially higher (p<0.05) in group B (median=6) than in groups A (median=2) and C (median=4). CONCLUSION: DECT was found to be superior to conventional CTA in foot arteriography, and beyond the lower extremity, it might be a general favourable solution for imaging regions with small vessels and reduced contrast medium.


Assuntos
Diabetes Mellitus , Pé Diabético , Imagem Radiográfica a Partir de Emissão de Duplo Fóton , Humanos , Tomografia Computadorizada por Raios X/métodos , Pé Diabético/diagnóstico por imagem , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Angiografia/métodos , Angiografia por Tomografia Computadorizada/métodos , Razão Sinal-Ruído , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Estudos Retrospectivos , Meios de Contraste
6.
Clin Radiol ; 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38789332

RESUMO

AIMS: To explore the MRI characteristics and clinical outcome of the "very early" intrahepatic cholangiocarcinoma (iCCA) ≤2.0cm. MATERIALS AND METHODS: Totally 213 pathologically confirmed iCCAs (44 ≤ 2.0cm and 169 of 2.0-5.0cm) from two institutes were included. Forty-four matching non-iCCA malignancies ≤2.0cm were also enrolled. Recurrence-free survival (RFS) was estimated and compared between iCCAs ≤2.0cm and 2.0-5.0cm. MRI features were analyzed and compared between iCCAs ≤2.0cm and 2.0-5.0cm, as well as between iCCAs ≤2.0cm and non-iCCAs ≤2.0cm. Univariate and multivariate regression analyses were performed to identify independent imaging features for discrimination. An MRI-based diagnostic model for iCCA ≤2.0cm was constructed by incorporating the independent imaging features. RESULTS: ICCAs ≤2.0cm had a significantly longer RFS than those of 2.0-5.0cm (log rank P=0.014). Imaging features of homogeneous signal (odds ratio (OR) = 6.677, P<0.001) and lack of vessel invasion (OR=7.56, P<0.001) were more frequently displayed in iCCAs ≤2.0cm compared to iCCAs of 2.0-5.0cm independently. In the small lesions ≤2.0cm, imaging features of progressive or persistent enhancement pattern (OR=27.78, P=0.002) and rim diffusion restriction (OR=5.70, P=0.027) were independent imaging features suggestive of iCCA over non-iCCA malignancy; their combination yielded an area under the curve value of 0.824, with a sensitivity of 97.73%. CONCLUSION: The "very early" iCCA ≤2.0cm was associated with a favorable outcome after surgery, it displayed different and relatively atypical imaging manifestations compared with those of 2.0-5.0cm. Furthermore, in the small lesions ≤ 2.0cm, MRI can be served as a useful non-invasive diagnostic tool for iCCA in clinical screening with high sensitivity.

7.
Rhinology ; 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38416565

RESUMO

BACKGROUND: Chronic rhinosinusitis with nasal polyps (CRSwNP) is characterized by tissue heterogeneity and high postoperative recurrence risk. This study aims to employ cytokine analyses to identify serum biomarkers associated with postoperative CRSwNP recurrence and elucidate underlying recurrent mechanisms. METHODS: A prospective cohort study was conducted on CRSwNP patients undergoing functional endoscopic sinus surgery. Serum and tissue samples were collected and analyzed for multiple cytokines. Participants were followed for 3 years and categorized into recurrent and non-recurrent groups. Cytokine profiles were compared, and potential markers for recurrence were further assessed. Macrophage migration inhibitory factor (MIF) expression in macrophages was modulated, and their polarization and cytokine secretion were assessed. RESULTS: In the discovery cohort (21 recurrent and 40 non-recurrent patients), circulating cytokine profiles differed significantly, with 8 cytokines showing differential expression between the two groups. Among them, serum eotaxin, MIF, RANTES, and TRAIL exhibited promise in predicting recurrence. In the validation cohort (24 recurrent and 44 non-recurrent patients), serum eotaxin, MIF, and TRAIL levels were higher in recurrent cases. Tissue MIF was elevated in recurrent cases and had a strong predictive value for recurrence. Moreover, tissue MIF was co-expressed with CD206 in recurrent cases. Mechanistically, MIF overexpression promoted macrophage M2 polarization and TGF-ß1, CCL-24, and MIF secretion, and MIF recombinant protein facilitated M2 polarization, and TGF-ß1 and CCL-24 production, contributing to CRSwNP recurrence. CONCLUSIONS: Serum-specific cytokine signatures were associated with postoperative recurrence risk in CRSwNP. Elevated MIF enhanced macrophage M2 polarization and cytokine secretion, contributing to the recurrent mechanisms of CRSwNP.

8.
Br Poult Sci ; : 1-7, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38717938

RESUMO

1. Non-coding RNAs, such as miRNAs, play a crucial role in chicken feather growth rate. However, circular RNA (circRNA) expression profiles in fast- and slow-feathering chickens that follow and do not follow Mendelian inheritance are unclear.2. The circRNA expression profiles was analysed by RNA sequencing of hair follicles of slow-feathering chickens that follow genetic rules and fast-feathering chickens that did not follow genetic rules. Differentially expressed circRNA-miRNA-mRNA competing endogenous RNA (ceRNA) network was then constructed and the key factors and regulation mechanisms controlling feather growth rate were identified.3. The results revealed that 67 circRNAs were significantly differentially expressed in hens, including 22 up-regulated and 45 down-regulated circRNAs in non-Mendelian inheritance-mediated fast-feathering hens compared with Mendelian inheritance-mediated slow-feathering hens. In addition, 16 significantly differentially expressed circRNAs were identified in cockerels, including nine up-regulated and seven down-regulated circRNAs in non-Mendelian inheritance-mediated fast- compared with Mendelian inheritance-mediated slow-feathering cocks. Moreover, circRNA-mediated ceRNA regulation of hair follicle formation was particularly abundant in the Jak-STAT, Wnt and Toll-like receptor signalling pathways. Furthermore, circABI3BP was seen to be a crucial circRNA in regulating feather growth rate, by binding with gga-miR-1649-5p to regulate SSTR2 expression.4. In conclusion, this study analysed circRNA expression profiles in fast- and slow-feathering chickens that follow and do not follow Mendelian inheritance, which laid the foundation for understanding the role of circRNA in chicken feather growth rate.

9.
Zhonghua Yi Xue Za Zhi ; 104(14): 1180-1183, 2024 Apr 09.
Artigo em Zh | MEDLINE | ID: mdl-38583050

RESUMO

A newly developed wearable balance diagnosis and treatment system was studied to evaluate the indexes of the abnormal balance function in patients with vestibular vertigo. A cross-sectional study was carried out. A total of 30 patients diagnosed with non-acute vestibular vertigo in the outpatient department of Eye, Ear, Nose and Throat Hospital Affiliated to Fudan University from July 2022 to May 2023 were selected as the vertigo group, including 13 males and 17 females, and aged (45.7±13.9) years. Meanwhile, 20 healthy controls (8 males and 12 females) were included as the control group, with a mean age of (43.6±8.0) years. The static balance and limits of stability (LOS) function of all subjects were assessed with wearable balance diagnosis and treatment system developed under the leadership of Eye & ENT Hospital of Fudan University. In the static balance test, the ratio of eyes open with cushions to eyes open without cushions in the vertigo group was less than that of the control group[1.20% (0.92%, 1.53%) vs 1.49% (1.22%, 1.81%), P=0.008], indicating that patients with non-acute vestibular vertigo may compensate static balance ability earlier. In vertigo group, the directional control in 8 directions, the maximum excursion in anterior, posterior, right anterior and right posterior directions, the endpoint excursion in the posterior, right posterior, and left posterior directions were all smaller than those of the control group (all P<0.05). The reaction time in the left posterior direction of vertigo group was longer than that of the control group (all P<0.05). Those results indicated that the directional control, maximum excursion and endpoint excursion of LOS could be considered as important reference indexes for dynamic balance function.


Assuntos
Vertigem , Dispositivos Eletrônicos Vestíveis , Masculino , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Estudos Transversais , Vertigem/diagnóstico , Vertigem/terapia , Pacientes Ambulatoriais , Equilíbrio Postural
10.
Zhonghua Xin Xue Guan Bing Za Zhi ; 52(2): 185-190, 2024 Feb 24.
Artigo em Zh | MEDLINE | ID: mdl-38326071

RESUMO

Objective: To investigate the influence of varied oxygen (O2) concentration environments on the phenotypic transformation of pulmonary artery smooth muscle cells (PASMC) and the mechanism of pulmonary hypertension. Methods: Primary rat PASMC were isolated and cultured through the process of enzymatic digestion. Following identification, the stable passaged PASMC were subjected to a 6-hour incubation in sealed containers with normal O2 content (group C) and relative O2 content comprising 55% (group H55), 75% (group H75), and 95% (group H95). mRNA and protein expression of α-Actin (α-SMA), smooth muscle 22α (SM22α), osteopontin (OPN), and matrix metalloproteinase-2 (MMP-2) were measured using real-time quantitative PCR and western blot analysis. Results: The H55 group displayed no significant difference from the C group in terms of mRNA and relative protein expression levels for α-SMA, SM22α, OPN, and MMP-2 (all P>0.05). On the other hand, groups H75 and H95 exhibited a reduction in mRNA and relative protein expression of α-SMA and SM22α, along with an increase in mRNA and relative protein expression of OPN and MMP-2 when compared with both the C and H55 groups (all P<0.05). The H95 group showed a higher relative mRNA expression of MMP-2 as compared to the H75 group (P<0.05). Conclusions: Oxygen concentration environments of 75% or higher can serve as the foundation for the pathogenesis of pulmonary hypertension, essentially by inducing a phenotypic transformation in PASMC towards adopting a robust secretory function. This induction is contingent upon the concentration of oxygen present.


Assuntos
Hiperóxia , Hipertensão Pulmonar , Ratos , Animais , Artéria Pulmonar/patologia , Metaloproteinase 2 da Matriz/genética , Hiperóxia/metabolismo , Hiperóxia/patologia , Actinas/genética , Actinas/metabolismo , Miócitos de Músculo Liso/metabolismo , Oxigênio/metabolismo , Fenótipo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Células Cultivadas
11.
Niger J Clin Pract ; 27(5): 599-603, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38842709

RESUMO

BACKGROUND AND AIM: Preeclampsia, a pregnancy complication associated with significant maternal and perinatal mortality and morbidity, has been found to be closely linked to dysfunction in the blood coagulation-fibrinolysis system. However, the relationship between hematologic data and severity and onset time of preeclampsia remains unclear. This study aimed to identify specific hematologic parameters in both preeclamptic and normotensive pregnant women and determine their potential significance in the pathogenesis of preeclampsia. MATERIALS AND METHODS: A total of 112 patients with gestational hypertension disease were divided into two groups: early-onset preeclampsia (32 cases) and late-onset preeclampsia (80 cases). A control group of 82 normotensive pregnant women matched for age and parity was also selected. Blood samples were collected from all participants to test for specific hematologic parameters. RESULTS: Mild and severe preeclampsia were associated with lower hemoglobin level (P = 0.01 and P = 0.03, respectively), higher mean platelet volume (P = 0.01 and P = 0.01, respectively) and fibrinogen (P = 0.01 and P = 0.01, respectively), and shorter prothrombin time (P = 0.02 and P = 0.01, respectively) and activated partial thromboplastin time (P = 0.01 and P = 0.02, respectively). CONCLUSION: These findings have provided evidence on the hematologic coagulative actors in the pathogenesis and severity of preeclampsia.


Assuntos
Pré-Eclâmpsia , Humanos , Feminino , Gravidez , Adulto , Pré-Eclâmpsia/sangue , Pré-Eclâmpsia/fisiopatologia , Pré-Eclâmpsia/diagnóstico , Estudos de Casos e Controles , Hipertensão Induzida pela Gravidez/sangue , Hipertensão Induzida pela Gravidez/fisiopatologia , Coagulação Sanguínea/fisiologia , Índice de Gravidade de Doença , Adulto Jovem , Fibrinogênio/metabolismo , Fibrinogênio/análise , Tempo de Protrombina , Volume Plaquetário Médio , Hemoglobinas/análise , Tempo de Tromboplastina Parcial
12.
Osteoarthritis Cartilage ; 31(6): 819-828, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36889626

RESUMO

OBJECTIVE: We primarily aimed to investigate whether there are phenotypic and genetic links underlying body mass index (BMI) and overall osteoarthritis (OA). We then intended to explore whether the relationships differ across sexes and sites. METHOD: We first evaluated the phenotypic association between BMI and overall OA using data from the UK Biobank. We then investigated the genetic relationship leveraging summary statistics of the hitherto largest genome-wide association studies performed for BMI and overall OA. Finally, we repeated all analyses in a sex- (female, male) and site- (knee, hip, spine) specific manner. RESULTS: Observational analysis suggested an increased hazard of diagnosed OA per 5 kg/m2 increment in BMI (hazard ratio = 1.38, 95% confidence interval (CI) = 1.37-1.39). A positive overall genetic correlation was observed for BMI and OA (rg = 0.43, P = 4.72 × 10-133), corroborated by 11 significant local signals. Cross-trait meta-analysis identified 34 pleiotropic loci shared between BMI and OA, of which seven were novel. Transcriptome-wide association study revealed 29 shared gene-tissue pairs, targeting nervous, digestive, and exo/endocrine systems. Mendelian randomization demonstrated a robust BMI-OA causal relationship (odds ratio = 1.47, 95% CI = 1.42-1.52). A similar pattern of effects was observed in sex- and site-specific analyses, with BMI affecting OA comparably in both sexes and most strongly in the knee. CONCLUSION: Our work demonstrates an intrinsic relationship underlying BMI and overall OA, reflected by a pronounced phenotypic association, significant biological pleiotropy, and a putative causal link. Stratified analysis further reveals that the effects are distinct across sites and comparable across sexes.


Assuntos
Osteoartrite do Joelho , Masculino , Feminino , Humanos , Índice de Massa Corporal , Osteoartrite do Joelho/epidemiologia , Osteoartrite do Joelho/genética , Estudo de Associação Genômica Ampla , Causalidade , Articulação do Joelho , Polimorfismo de Nucleotídeo Único
13.
Plant Cell Environ ; 46(5): 1540-1561, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36760139

RESUMO

A photochemical model of photosynthetic electron transport (PET) is needed to integrate photophysics, photochemistry, and biochemistry to determine redox conditions of electron carriers and enzymes for plant stress assessment and mechanistically link sun-induced chlorophyll fluorescence to carbon assimilation for remotely sensing photosynthesis. Towards this goal, we derived photochemical equations governing the states and redox reactions of complexes and electron carriers along the PET chain. These equations allow the redox conditions of the mobile plastoquinone pool and the cytochrome b6 f complex (Cyt) to be inferred with typical fluorometry. The equations agreed well with fluorometry measurements from diverse C3 /C4 species across environments in the relationship between the PET rate and fraction of open photosystem II reaction centres. We found the oxidation of plastoquinol by Cyt is the bottleneck of PET, and genetically improving the oxidation of plastoquinol by Cyt may enhance the efficiency of PET and photosynthesis across species. Redox reactions and photochemical and biochemical interactions are highly redundant in their complex controls of PET. Although individual reaction rate constants cannot be resolved, they appear in parameter groups which can be collectively inferred with fluorometry measurements for broad applications. The new photochemical model developed enables advances in different fronts of photosynthesis research.


Assuntos
Clorofila , Complexo de Proteína do Fotossistema I , Transporte de Elétrons , Complexo de Proteína do Fotossistema I/metabolismo , Clorofila/química , Fotossíntese , Oxirredução , Plastoquinona , Complexo Citocromos b6f/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo
14.
Opt Express ; 31(4): 6327-6341, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36823892

RESUMO

To improve the color conversion performance, we study the nanoscale-cavity effects on the emission efficiency of a colloidal quantum dot (QD) and the Förster resonance energy transfer (FRET) from quantum well (QW) into QD in a GaN porous structure (PS). For this study, we insert green-emitting QD (GQD) and red-emitting QD (RQD) into the fabricated PSs in a GaN template and a blue-emitting QW template, and investigate the behaviors of the photoluminescence (PL) decay times and the intensity ratios of blue, green, and red lights. In the PS samples fabricated on the GaN template, we observe the efficiency enhancements of QD emission and the FRET from GQD into RQD, when compared with the samples of surface QDs, which is attributed to the nanoscale-cavity effect. In the PS samples fabricated on the QW template, the FRET from QW into QD is also enhanced. The enhanced FRET and QD emission efficiencies in a PS result in an improved color conversion performance. Because of the anisotropic PS in the sample surface plane, the polarization dependencies of QD emission and FRET are observed.

15.
Opt Express ; 31(10): 16010-16024, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37157689

RESUMO

To improve color conversion performance for color display application, we study the near-field-induced nanoscale-cavity effects on the emission efficiency and Förster resonance energy transfer (FRET) under the condition of surface plasmon (SP) coupling by inserting colloidal quantum dots (QDs) and synthesized Ag nanoparticles (NPs) into surface nano-holes fabricated on a GaN template and an InGaN/GaN quantum-well (QW) template. In the QW template, the inserted Ag NPs are close to either QWs or QDs for producing three-body SP coupling to enhance color conversion. Time-resolved and continuous-wave photoluminescence (PL) behaviors of the QW- and QD-emitting lights are investigated. The comparison between the nano-hole samples and the reference samples of surface QD/Ag NP shows that the nanoscale-cavity effect of the nano-hole leads to the enhancements of QD emission, FRET between QDs, and FRET from QW into QD. The SP coupling induced by the inserted Ag NPs can enhance the QD emission and FRET from QW into QD. Its result is further enhanced through the nanoscale-cavity effect. The relative continuous-wave PL intensities among different color components also show the similar behaviors. By introducing SP coupling to a color conversion device with the FRET process in a nanoscale cavity structure, we can significantly improve the color conversion efficiency. Simulation results confirm the basic observations in experiment.

16.
J Chem Phys ; 159(8)2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37606334

RESUMO

A hybrid stochastic simulation method is developed to study H2-O2 auto-ignition at the microscale. Simulation results show that the discrete and stochastic characteristics of reaction collisions have notable impacts on the ignition process, particularly in the early stages when only a few radicals exist. The statistical properties of ignition delay time, which reflect the accumulated stochasticity during ignition, are obtained and analyzed for different initial temperatures and total molecular numbers. It is found that the average and standard deviation of ignition delay time increase as the total molecular number decreases, with this phenomenon being particularly pronounced near the crossover temperature. When the total molecular number is sufficiently small, the chain initiation reaction becomes crucial to the stochastic properties, as its average firing time exhibits an inverse proportionality to the total molecular number. As the total molecular number increases, the influence of other chain reactions intensifies, causing the power law relation between standard deviation and total molecular number to shift from -1 power to -0.5 power. Owing to different chain reaction paths for high- and low-temperature auto-ignition, the strongest relative fluctuation occurs near the crossover temperature. A theoretical equation for the standard deviation of ignition delay time is obtained based on dimensional analysis, giving excellent agreement with the simulation results in both high- and low-temperature modes.

17.
Climacteric ; 26(6): 583-593, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37477999

RESUMO

OBJECTIVE: The ApaI polymorphism (G > T, rs7975232) of the vitamin D receptor (VDR) gene in the risk of postmenopausal osteoporosis has been widely researched, and the results have yielded conflicts. Therefore, we performed an updated pooled analysis to comprehensively assess the association between VDR ApaI polymorphism and postmenopausal osteoporosis risk. METHODS: We searched eligible studies about ApaI polymorphism and osteoporosis through the PubMed, Embase, CNKI and Wanfang databases; case-control studies containing available genotype frequencies of A/a were chosen. We used the odds ratio with 95% confidence interval to assess the strength of this association. Sensitivity analysis and publication bias assessment were performed. Trial sequential analysis (TSA) was performed to evaluate a sufficient sample. RESULTS: Twenty-two studies assessed the relationship between ApaI polymorphism and the risk of osteoporosis in postmenopausal women. The comprehensive analyses showed no significant association for ApaI polymorphism with postmenopausal osteoporosis in the overall population, equally valid for Asian and Caucasian subgroups with any genetic model. TSA still indicated the results were robust. CONCLUSION: The present meta-analysis suggests that the VDR ApaI genotype may not affect the risk of postmenopausal osteoporosis in Asians and Caucasians.


Assuntos
Osteoporose Pós-Menopausa , Osteoporose , Feminino , Humanos , Osteoporose Pós-Menopausa/genética , Predisposição Genética para Doença , Receptores de Calcitriol/genética , Polimorfismo Genético
18.
Climacteric ; 26(1): 64-71, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36459490

RESUMO

OBJECTIVE: Triple-negative breast cancer (TNBC) is highly aggressive and leads to a poor prognosis. microRNA-181a (miR-181a) exhibits strong antineoplastic effects in many types of cancer. In this study, we examine the responses of human miR-181a-transfected TNBC cells and explore the mechanisms underlying the observed effects. METHODS: A series of cellular assays were conducted using cells from the MDA-MB-231 TNBC line to assess the impact of miR-181a overexpression. The extracellular acidification rate, lactate production and glucose uptake were evaluated as a measure of aerobic glycolysis (i.e. the Warburg effect). The expressions of glycolysis-related gene were analyzed. RESULTS: Viability, migration and survival of miR-181a-transfected MDA-MB-231 cells were all significantly reduced. miR-181a inhibited glycolysis in TNBC cells by reducing the rates of glucose uptake and lactate production and a substantial downregulation of factors known to contribute to the Warburg effect, including the serine/threonine kinase, AKT3, hypoxia-inducible factor-1α (HIF-1α) and progesterone receptor membrane component 1 (PGRMC1). CONCLUSION: Our results demonstrate that miR-181a may regulate glycolysis in MDA-MB-231 TNBC cells, potentially via interference with components of the AKT3-HIF-1α and PGRMC1 pathways. These results suggest that miR-181a might be developed as a therapeutic agent for use in antineoplastic regimens directed at TNBC and PGRMC1-overexpressing breast cancers.


Assuntos
MicroRNAs , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo , MicroRNAs/genética , Glucose , Proliferação de Células , Proteínas de Membrana , Receptores de Progesterona
19.
J Endocrinol Invest ; 46(6): 1177-1185, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36436189

RESUMO

PURPOSE: Prepubescent body fat percentage (BFP) is associated with puberty onset; however, the association between the timing of puberty onset and BFP remains unclear. This study aimed to determine whether and how the timing of puberty onset is associated with various anthropometric measures, and to investigate the critical time period of the BFP transition before and after puberty. METHODS: The Taiwan Pubertal Longitudinal Study (TPLS) has a multicenter, population-based prospective cohort and was established in July 2018 at 4 pediatric departments. We included girls aged 6-14 years and boys aged 9-17 years evaluated as having puberty onset and excluded those with precocious puberty diagnosis. The anthropometric measures were collected every 3 months. The main outcome was age at puberty onset. Data were analyzed between July 2018 and September 2020. RESULTS: For 153 girls and 83 boys, BFP was significantly related to puberty onset for girls. Longitudinal analysis revealed that BFP in the girls was reduced to less than 18% 6 months before puberty and rapidly increased by 2.85% over 3 months, then exceeding 20% before puberty onset. After puberty onset, BFP was no longer lower than 22%. CONCLUSIONS: BFP is an essential predictor of age at puberty onset. BFP first decreases and then begins to increase 3-6 months before puberty in girls. Parents and schools could monitor the BFP of prepubescent girls every 6 months to predict puberty onset.


Assuntos
Puberdade Precoce , Puberdade , Masculino , Criança , Feminino , Humanos , Estudos Longitudinais , Estudos Prospectivos , Taiwan/epidemiologia , Puberdade Precoce/diagnóstico , Puberdade Precoce/epidemiologia , Tecido Adiposo
20.
Langenbecks Arch Surg ; 408(1): 202, 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37209306

RESUMO

PURPOSE: Postoperative wound complications are common in patients undergoing resection of lower extremity soft tissue tumors. Postoperative drainage therapy ensures adequate wound healing but may delay or complicate it. The aim of this study is to evaluate the incidence of postoperative wound complications and delayed or prolonged drainage treatment and to propose a standardized definition and severity grading of complex postoperative courses. METHODS: A monocentric retrospective analysis of 80 patients who had undergone primary resection of lower extremity soft tissue tumors was performed. A new classification was developed, which takes into account postoperative drainage characteristics and wound complications. Based on this classification, risk factors and the prognostic value of daily drainage volumes were evaluated. RESULTS: According to this new definition, regular postoperative course grade 0 (no wound complication and timely drainage removal) occurred in 26 patients (32.5%), grade A (minor wound complications or delayed drainage removal) in 12 (15.0%), grade B (major wound complication or prolonged drainage therapy) in 31 (38.8%), and grade C (reoperation) in 11 (13.7%) patients. Tumor-specific characteristics, such as tumor size (p = 0.0004), proximal tumor location (p = 0.0484), and tumor depth (p = 0.0138) were identified as risk factors for complex postoperative courses (grades B and C). Drainage volume on postoperative day 4 was a suitable predictor for complex courses (cutoff of 70 ml/d). CONCLUSION: The proposed definition incorporates wound complications and drainage management while also being clinically relevant and easy to apply. It may serve as a standardized endpoint for assessing the postoperative course after resection of lower extremity soft tissue tumors.


Assuntos
Sarcoma , Neoplasias de Tecidos Moles , Humanos , Estudos Retrospectivos , Radioterapia Adjuvante/efeitos adversos , Sarcoma/patologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/terapia , Extremidade Inferior/cirurgia , Neoplasias de Tecidos Moles/cirurgia , Neoplasias de Tecidos Moles/patologia , Drenagem/efeitos adversos
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