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1.
Science ; 384(6692): 185-189, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38603510

RESUMO

Ultrahigh-power-density multilayer ceramic capacitors (MLCCs) are critical components in electrical and electronic systems. However, the realization of a high energy density combined with a high efficiency is a major challenge for practical applications. We propose a high-entropy design in barium titanate (BaTiO3)-based lead-free MLCCs with polymorphic relaxor phase. This strategy effectively minimizes hysteresis loss by lowering the domain-switching barriers and enhances the breakdown strength by the high atomic disorder with lattice distortion and grain refining. Benefiting from the synergistic effects, we achieved a high energy density of 20.8 joules per cubic centimeter with an ultrahigh efficiency of 97.5% in the MLCCs. This approach should be universally applicable to designing high-performance dielectrics for energy storage and other related functionalities.

2.
Brief Bioinform ; 24(6)2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37985452

RESUMO

Charting microRNA (miRNA) regulation across pathways is key to characterizing their function. Yet, no method currently exists that can quantify how miRNAs regulate multiple interconnected pathways or prioritize them for their ability to regulate coordinate transcriptional programs. Existing methods primarily infer one-to-one relationships between miRNAs and pathways using differentially expressed genes. We introduce PanomiR, an in silico framework for studying the interplay of miRNAs and disease functions. PanomiR integrates gene expression, mRNA-miRNA interactions and known biological pathways to reveal coordinated multi-pathway targeting by miRNAs. PanomiR utilizes pathway-activity profiling approaches, a pathway co-expression network and network clustering algorithms to prioritize miRNAs that target broad-scale transcriptional disease phenotypes. It directly resolves differential regulation of pathways, irrespective of their differential gene expression, and captures co-activity to establish functional pathway groupings and the miRNAs that may regulate them. PanomiR uses a systems biology approach to provide broad but precise insights into miRNA-regulated functional programs. It is available at https://bioconductor.org/packages/PanomiR.


Assuntos
MicroRNAs , MicroRNAs/metabolismo , Biologia de Sistemas , Perfilação da Expressão Gênica/métodos , Biologia Computacional/métodos , Redes Reguladoras de Genes
3.
Environ Pollut ; 336: 122404, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37625772

RESUMO

Antimicrobial resistance (AMR) is a serious issue that is continuously growing and spreading, leading to a dwindling number of effective treatments for infections that were easily treatable with antibiotics in the past. Animal farms are a major hotspot for AMR, where antimicrobials are often overused, misused, and abused, in addition to overcrowding of animals. In this study, we investigated the risk of AMR transmission from a farm to nearby residential areas by examining the overall occurrence of endotoxins, antibiotic resistance genes (ARGs), and mobile genetic elements (MGEs) in the air of a cattle farm. We assessed various factors, including the season and year, day and nighttime, and different locations within the farm building and its vicinity. The most abundant ARGs detected were tetW, aadA1, and sul2, genes that encode for resistances towards antibiotics commonly used in veterinary medicine. While there was a clear concentration gradient for endotoxin from the middle of the farm building to the outside areas, the abundance of ARGs and MGEs was relatively uniform among all locations within the farm and its vicinity. This suggests that endotoxins preferentially accumulated in the coarse particle fraction, which deposited quickly, as opposed to the ARGs and MGEs, which might concentrate in the fine particle fraction and remain longer in the aerosol phase. The occurrence of the same genes found in the air samples and in the manure indicated that ARGs and MGEs in the air mostly originated from the cows, continuously being released from the manure to the air. Although our atmospheric dispersion model indicated a relatively low risk for nearby residential areas, farm workers might be at greater risk of getting infected with resistant bacteria and experiencing overall respiratory tract issues due to continuous exposure to elevated concentrations of endotoxins, ARGs and MGEs in the air of the farm.


Assuntos
Endotoxinas , Genes Bacterianos , Animais , Bovinos , Fazendas , Endotoxinas/genética , Antibacterianos/farmacologia , Esterco/microbiologia , Resistência Microbiana a Medicamentos/genética , Alemanha , Sequências Repetitivas Dispersas
4.
Am J Perinatol ; 40(15): 1611-1617, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-35580627

RESUMO

Congenital heart defects (CHDs) are the most common neonatal malformations and are a leading cause of infant death in developed countries. Finding safe and effective diagnostic methods to screen for CHDs is important. The aim of this study was to evaluate the effectiveness of pulse oximetry (PO) and perfusion index (PI) in screening CHD. We conducted a systematic review of studies in PubMed, Embase, and the Cochrane Library published on or before October 1, 2021. Studies based on PICOS were included in this systematic review. The flow chart is made by PRISMA software. The quality of included studies was assessed by RevMan5 software (QUADAS-2: Quality Assessment of Diagnostic Accuracy Studies-2). The sensitivity, specificity, and other measurements of accuracy were pooled using Stata/SE 12.0 software. Five studies containing 46,965 neonates were included in this study. A randomized-effects model was used for the meta-analysis because of significant heterogeneity. The combined sensitivity and specificity were 0.82 (95% confidence interval [CI], 0.53-0.95) and 0.97 (95% CI, 0.57-1.00), respectively. The area under the curve was 0.92 (95% CI, 0.89-0.94). The combination PO and PI was significant in CHD screening. Once diagnosed by the combined method, it means that the neonate is most likely to have a CHD. KEY POINTS: · Pulse oximetry and PI screening.. · Congenital heart defects.. · A systematic review and meta-analysis..


Assuntos
Cardiopatias Congênitas , Índice de Perfusão , Recém-Nascido , Lactente , Humanos , Triagem Neonatal/métodos , Oximetria/métodos , Sensibilidade e Especificidade , Cardiopatias Congênitas/diagnóstico
5.
J Fr Ophtalmol ; 45(10): 1177-1183, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36357250

RESUMO

PURPOSE: To investigate the relationship between levels of transforming growth factor beta (TGF-beta), matrix metalloproteinase (MMP) and tissue inhibitors of MMP (TIMP) in the aqueous humor (AH) and plasma (PL) of myopic patients. METHODS: Aqueous humor and plasma were collected intraoperatively from 37 myopic patients with various axial lengths (AL) during ICL surgery. The concentrations of TGF-ß1, TGF-ß2, TGF-ß3, MMP-1, MMP-2, MMP-7, MMP-9, MMP-10, TIMP-1, TIMP-2, TIMP-3 and TIMP-4 were measured using Luminex xMAP Technology kits (Milliplex xMAP kits). The association between TGFß and MMP/TIMP levels were analyzed based on the Spearman's correlation test or Pearson's correlation test. RESULTS: There was a negative correlation between TGF-ß1 and MMP-1, TIMP-2, TIMP-3 and TIMP-4 in the AH, and a positive correlation between TGF-ß1 and MMP-1 in the PL. In the AH, levels of TGF-ß2 were positively correlated with levels of TIMP-3 (r=0.441; P < 0.001). In the PL, levels of TGF-ß2 also correlated positively with levels of TIMP-3 (r=0.427; P < 0.001)). CONCLUSION: The level of TGF-ß2 was the highest among TGF-ßs in the AH. A consistent positive correlation between TGF-ß2 and TIMP-3 was found both in the AH and PL, indicating that systemic levels of TGF-ß2 and MMPs/TIMPs may also play a role in myopic progression.


Assuntos
Miopia , Fator de Crescimento Transformador beta2 , Humanos , Humor Aquoso , Inibidor Tecidual de Metaloproteinase-3 , Inibidor Tecidual de Metaloproteinase-2 , Fator de Crescimento Transformador beta1 , Metaloproteinase 1 da Matriz , Fatores de Crescimento Transformadores
7.
Pulm Circ ; 12(3): e12082, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35864910

RESUMO

Severe pulmonary hypertension (PH) is not common even in patients with severe chronic lung disease (CLD) but data on hemodynamic characteristics among patients with severe CLD is scarce. All adult patients who had right heart catheterization for lung transplant assessment for severe CLD in the only lung transplant service and for PAH management in the only tertiary pulmonary hypertension service in Hong Kong from 2010 to 2020 were included and classified into CLD group and PAH group. Patient characteristics and hemodynamic parameters were analyzed. There were 153 patients included with 106 patients in the CLD group and 47 in the PAH group. There were only 19.8% of the patients in the CLD group had severe pulmonary hypertension. Patients in the CLD group had significantly lower systolic pulmonary arterial pressure (PAPs), lower mean pulmonary arterial pressure (PAPm), higher cardiac index, and lower PVR when compared with the PAH group (p < 0.001). The area under curve (AUC) of PAPs, PAPm, and PVR were excellent, 0.973, 0.970, and 0.938, respectively for discrimination between CLD and PAH on receiver operator characteristics curve analysis. Optimal cutoff values were 55.5 mmHg, 35.5 mmHg, and 6.1 Wood Units for PAPs, PAPm, and PVR with Youden Index 0.85, 0.80, and 0.82, respectively. There were distinct hemodynamic characteristics between the CLD group and the PAH group. Systolic pulmonary arterial pressure, mean pulmonary arterial pressure, and pulmonary vascular resistance are useful to discriminate between the phenotype of severe CLD and PAH.

8.
Nature ; 606(7916): 873-877, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35676486

RESUMO

The dispersive sweep of fast radio bursts (FRBs) has been used to probe the ionized baryon content of the intergalactic medium1, which is assumed to dominate the total extragalactic dispersion. Although the host-galaxy contributions to the dispersion measure appear to be small for most FRBs2, in at least one case there is evidence for an extreme magneto-ionic local environment3,4 and a compact persistent radio source5. Here we report the detection and localization of the repeating FRB 20190520B, which is co-located with a compact, persistent radio source and associated with a dwarf host galaxy of high specific-star-formation rate at a redshift of 0.241 ± 0.001. The estimated host-galaxy dispersion measure of approximately [Formula: see text] parsecs per cubic centimetre, which is nearly an order of magnitude higher than the average of FRB host galaxies2,6, far exceeds the dispersion-measure contribution of the intergalactic medium. Caution is thus warranted in inferring redshifts for FRBs without accurate host-galaxy identifications.

9.
Nature ; 601(7891): 49-52, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34987214

RESUMO

Magnetic fields have an important role in the evolution of interstellar medium and star formation1,2. As the only direct probe of interstellar field strength, credible Zeeman measurements remain sparse owing to the lack of suitable Zeeman probes, particularly for cold, molecular gas3. Here we report the detection of a magnetic field of +3.8 ± 0.3 microgauss through the H I narrow self-absorption (HINSA)4,5 towards L15446,7-a well-studied prototypical prestellar core in an early transition between starless and protostellar phases8-10 characterized by a high central number density11 and a low central temperature12. A combined analysis of the Zeeman measurements of quasar H I absorption, H I emission, OH emission and HINSA reveals a coherent magnetic field from the atomic cold neutral medium (CNM) to the molecular envelope. The molecular envelope traced by the HINSA is found to be magnetically supercritical, with a field strength comparable to that of the surrounding diffuse, magnetically subcritical CNM despite a large increase in density. The reduction of the magnetic flux relative to the mass, which is necessary for star formation, thus seems to have already happened during the transition from the diffuse CNM to the molecular gas traced by the HINSA. This is earlier than envisioned in the classical picture where magnetically supercritical cores capable of collapsing into stars form out of magnetically subcritical envelopes13,14.

10.
Earths Future ; 10(12): e2022EF002674, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37035441

RESUMO

Afforestation and land use changes that sequester carbon from the atmosphere in the form of woody biomass have turned southern China into one of the largest carbon sinks globally, which contributes to mitigating climate change. However, forest growth saturation and available land that can be forested limit the longevity of this carbon sink, and while a plethora of studies have quantified vegetation changes over the last decades, the remaining carbon sink potential of this area is currently unknown. Here, we train a model with multiple predictors characterizing the heterogeneous landscapes of southern China and predict the biomass carbon carrying capacity of the region for 2002-2017. We compare observed and predicted biomass carbon density and find that during about two decades of afforestation, 2.34 PgC have been sequestered between 2002 and 2017, and a total of 5.32 Pg carbon can potentially still be sequestrated. This means that the region has reached 73% of its aboveground biomass carbon carrying capacity in 2017, which is 12% more than in 2002, equal to a decrease of 0.77% per year. We identify potential afforestation areas that can still sequester 2.39 PgC, while old and new forests have reached 87% of their potential with 1.85 PgC remaining. Our work locates areas where vegetation has not yet reached its full potential but also shows that afforestation is not a long-term solution for climate change mitigation.

12.
J Colloid Interface Sci ; 606(Pt 2): 1983-1997, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34695763

RESUMO

Materials made of synthetic vitreous mineral fibers, such as stone wool, are widely used in construction, in functional composites and as thermal and acoustic insulation. Chemical stability is an important parameter in assessing long term durability of the products. Stability is determined by fiber resistivity to dissolution, where the controlling parameters are solid surface area to solution volume ratio (S/V), pH and composition of the fibers and organic compounds used as binders. We investigated stone wool dissolution under flow through conditions, far from equilibrium, at pH range of 2 to 13, as well as under batch conditions, close to equilibrium, for up to 28 days, where S/V ranged from 100 to 10000 m-1. The dissolution rate of stone wool shows minimum at pH 8.5 and increases significantly at pH < 4.5 and pH > 12. In close to equilibrium conditions, S/V defines the steady state concentration for the leached components. Decreased dissolution rate could result from evolution of a surface leached layer or the formation of secondary surface phases or both. We suggested three dissolution rate controlling mechanisms, which depend on pH. That is, dissolution is controlled by: a SiO2 rich surface layer at pH < 4.5; by adsorption of an Al and Al-Si mixed surface layer at 5 < pH < 11 and by divalent cation adsorption and formation of secondary phases (silicates, hydroxides) at pH âˆ¼ 13. The organic compounds, used to treat the stone wool fibers during manufacture, had no influence on their dissolution properties.

13.
Zhonghua Liu Xing Bing Xue Za Zhi ; 42(8): 1365-1370, 2021 Aug 10.
Artigo em Chinês | MEDLINE | ID: mdl-34814555

RESUMO

Objective: To analyze the epidemiological and clinical characteristics of imported COVID-19 cases after SARS-CoV-2 vaccination and to provide evidence for the prevention and control of COVID-19. Methods: The imported COVID-19 cases in Chengdu as of April 15, 2021 were divided into the vaccinated group and unvaccinated group according to the history of SARS-CoV-2 vaccination. The epidemiological and clinical data of the cases were collected retrospectively, and the differences in epidemiological and clinical characteristics of the two groups were compared. Laboratory tests consisted of nucleic acid test, clinical index test, serum antibody test and lymphocyte test. Software WPS2019 was used for data management and software R 4.0.3 was used for statistical analysis. Results: A total of 75 COVID-19 cases were included in the analysis, in which 20 had received SARS-CoV-2 vaccination and only 4 with clinical symptoms, 55 patients did not receive SARS-CoV-2 vaccination, and 16 had clinical symptoms. In vaccinated group, the first injection time of vaccination ranged from July to November 2020, and 10 cases received two doses of vaccine simultaneously and 10 cases received two doses of vaccine at intervals of 14-57 days. The intervals between the completion of vaccination and the onset ranged from 87 days to 224 days. The differences in classification and clinical type between the two groups were significant. Significant differences were observed in case classification and clinical type between vaccinated group and unvaccinated group (P<0.05). The vaccinated group had a relatively high proportion of asymptomatic infections (40.00%, 8/20), while mild infections were mainly observed in the unvaccinated group(76.36%,42/55). The differences in Ct values (ORF1ab gene and N gene) at the diagnosis were not significant between vaccinated group and unvaccinated group (P>0.05), similar results were also observed in lymphocyte subtypes, procalcitonin and C-reactive protein level comparisons. Serum amyloid A level was higher in unvaccinated group than in vaccinated group (P<0.05). However, the SARS-CoV-2 related serum antibody of IgM, IgG and total antibody levels were significantly higher in vaccinated group (P<0.05). Conclusions: Risk of infection still exists with SARS-CoV-2 after vaccination, which can facilitate the production of specific serum antibody of IgM and IgG when people are exposed to the virus. It has a certain protective effect on SARS-CoV-2 infected persons. Vaccination can reduce the clinical symptoms and mitigate disease severity.


Assuntos
Vacinas contra COVID-19/administração & dosagem , COVID-19 , Anticorpos Antivirais/sangue , COVID-19/epidemiologia , China/epidemiologia , Humanos , Estudos Retrospectivos , Vacinação
14.
Zhonghua Yu Fang Yi Xue Za Zhi ; 55(10): 1240-1244, 2021 Oct 06.
Artigo em Chinês | MEDLINE | ID: mdl-34706511

RESUMO

An epidemiological investigation was carried out on a local cluster of outbreak caused by imported cases of Coronavirus Disease 2019 (COVID-19) in rural areas of Chengdu in December 2020, to find out the source of infection and the chain of transmission. According to Prevention and Control Protocol for COVID-19 (Version 7), field epidemiological investigation was adopted, combined with big data technology, video image investigation, gene sequencing and other methods to carry out investigation into COVID-19 cases and infections source tracing, analyze the epidemiological association, and map the chain of transmission. From December 7 to 17, 2020, 13 local COVID-19 confirmed cases and 1 asymptomatic case were diagnosed in Chengdu, of which 12 cases (85.71%) had a history of residence and activity in the village courtyard of Taiping (TP), Pidu (P) District, Chengdu. From November 8, 2020 to November 28, 2020, a group of inbound people form Nepal were transferred to the designated entry personnel quarantine hotel of P District which was adjacent to the TP village. During quarantine, there were 5 cases who tested positive for COVID-19. Through gene sequencing alignment, genes of local cases and Nepalese imported cases from the same period are homologous, all belong to the lineage of L2.2.3 (B.1.36 according to Pangolin lineage typing method). According to the results of field epidemiological investigation and gene sequencing analysis, the index case was most likely infected by contact with household waste of quarantine site. Under the situation of normalization prevention and control of COVID-19, sentinel monitoring of fever clinics in primary medical institutions is the key to early detection of the epidemic. The multi-department joint epidemiological investigation and the application of gene technology are the core links of the investigation and traceability of modern infectious diseases. The allocation of public health resources in rural areas needs to be strengthened. We need to improve the capacity for early surveillance and early warning of the epidemic in rural areas.


Assuntos
COVID-19 , Epidemias , Surtos de Doenças , Humanos , Quarentena , SARS-CoV-2
15.
Public Health ; 199: 107-109, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34601152

RESUMO

OBJECTIVES: Although a number of cases of importation with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection have been reported, there are still no data available concerning the characteristics in the coronavirus disease 2019 (COVID-19) cluster of charter flight importation. Here, we provide an analysis of COVID-19 cases and their close contacts who worked for the same company on a project in Karbala, Iraq, and returned back to Chengdu, China, by a charter flight. METHODS: The data of imported COVID-19 cases and their close contacts were obtained from National Notifiable Disease Report System of Chinese Center for Disease Control and Prevention and field epidemiological investigation reports by Centers for Disease Control and Prevention (CDCs) in Chengdu. The information of general characteristics and laboratory findings of this cluster were collected and summarized. RESULTS: One hundred and six (66.67%) of 159 charter flight passengers tested positive for COVID-19 before entry. Through treatment, all 159 people tested negative and meet the requirements of taking flights bound for China before boarding. However, there has been still 36 (22.64%) of them tested positive after entry. The median time from entry to confirmation was 1.0 day (Interquartile Range (IQR): 0-4.3). The Cycle threshold value (Ct value) of 36 patients' positive samples are all above 30 and most values are above 35. CONCLUSIONS: In conclusion, there is still a risk that a number of COVID-19 cases can be imported through charter flight. However, the infectivity of confirmed patients of the charter flight was considered to be low.


Assuntos
COVID-19 , China/epidemiologia , Humanos , Iraque/epidemiologia , SARS-CoV-2 , Inquéritos e Questionários , Estados Unidos
16.
Nature ; 598(7880): 267-271, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34645999

RESUMO

The event rate, energy distribution and time-domain behaviour of repeating fast radio bursts (FRBs) contain essential information regarding their physical nature and central engine, which are as yet unknown1,2. As the first precisely localized source, FRB 121102 (refs. 3-5) has been extensively observed and shows non-Poisson clustering of bursts over time and a power-law energy distribution6-8. However, the extent of the energy distribution towards the fainter end was not known. Here we report the detection of 1,652 independent bursts with a peak burst rate of 122 h-1, in 59.5 hours spanning 47 days. A peak in the isotropic equivalent energy distribution is found to be approximately 4.8 × 1037 erg at 1.25 GHz, below which the detection of bursts is suppressed. The burst energy distribution is bimodal, and well characterized by a combination of a log-normal function and a generalized Cauchy function. The large number of bursts in hour-long spans allows sensitive periodicity searches between 1 ms and 1,000 s. The non-detection of any periodicity or quasi-periodicity poses challenges for models involving a single rotating compact object. The high burst rate also implies that FRBs must be generated with a high radiative efficiency, disfavouring emission mechanisms with large energy requirements or contrived triggering conditions.

17.
Zhonghua Yi Xue Za Zhi ; 101(29): 2293-2298, 2021 Aug 03.
Artigo em Chinês | MEDLINE | ID: mdl-34333944

RESUMO

Objective: Propose a new risk classification system for blunt thoracic aortic injury and explore its treatment strategies. Methods: After the retrospective analysis of clinical data from 68 patients with blunt thoracic aortic injury in the First Affiliated Hospital of Zhengzhou University from November 2016 to October 2020, there were 56 males and 12 females, among these patients, the median age was 45(21-69). According to the degree of aortic injury and the combined injury, the patients were scored for aortic injury, and the risk of the patients were graded into following three types: low-risk group (score ≤ 2 points) 12 cases, intermediate-risk group (3 points ≤ score ≤ 5 points) 41 cases, high-risk group (score ≥ 6 points) 15 cases. Analyzing the effects of treatments received by patients in different grades on the prognosis. Patients were followed up through hospitalization or outpatient clinics at 1, 3, 6, 12 months after surgery and every year thereafter. Results: Of the 68 patients, 21 received non-surgical treatment and 47 received surgical repair, including 6 open surgery and 41 thoracic aortic endovascular repair. There were 16 cases of emergency operation and 31 cases of delayed operation. Twelve low-risk patients were treated with non-surgical treatment, and only 1 patient died of lung infection, with a mortality rate of 8.3% (1/12). There were 8 deaths in 41 moderate-risk patients, with a mortality rate of 19.5% (8/41), and the aortic-related mortality rate was 9.8% (4/41), and the operative mortality rate was 10.8% (4/37). The total mortality of 15 high-risk patients was 40% (6/15), and the aortic-related mortality rate was 30.0% (5/15), and the mortality rate of surgical patients was 10% (1/10). During the follow-up period of 5 to 52 months, no deaths occurred outside the hospital. According to the risk grading, there were significant differences in the aortic-related mortality of each grade (χ²=7.840, P=0.020). During the follow-up of 5-52 months, 1 case had type Ⅰ endoleak, 1 case of cerebral infarction, and 1 case of acute renal failure. Conclusion: According to the patient's degree of aortic injury and combined injury, the risk classification helps to choose the appropriate treatment.


Assuntos
Implante de Prótese Vascular , Procedimentos Endovasculares , Traumatismos Torácicos , Ferimentos não Penetrantes , Adulto , Idoso , Aorta Torácica/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Traumatismos Torácicos/cirurgia , Resultado do Tratamento , Ferimentos não Penetrantes/cirurgia , Adulto Jovem
18.
Opt Express ; 29(11): 17029-17041, 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34154254

RESUMO

In cold atom experiments, each image of light refracted and absorbed by an atomic ensemble carries a remarkable amount of information. Numerous imaging techniques including absorption, fluorescence, and phase-contrast are commonly used. Other techniques such as off-resonance defocused imaging (ORDI, [1-4]), where an in-focus image is deconvolved from a defocused image, have been demonstrated but find only niche applications. The ORDI inversion process introduces systematic artifacts because it relies on regularization to account for missing information at some spatial frequencies. In the present work, we extend ORDI to use multiple cameras simultaneously at degrees of defocus, eliminating the need for regularization and its attendant artifacts. We demonstrate this technique by imaging Bose-Einstein condensates, and show that the statistical uncertainties in the measured column density using the multiple-camera off-resonance defocused (McORD) imaging method are competitive with absorption imaging near resonance and phase contrast imaging far from resonance. Experimentally, the McORD method may be incorporated into existing set-ups with minimal additional equipment.

19.
Bratisl Lek Listy ; 122(6): 396-404, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34002613

RESUMO

OBJECTIVE: To investigate the possible molecular mechanisms of radiofrequency ablation (RFA) for treating atrial fibrillation (AF) and the microRNA (miRNA) target for intervention in the future. METHODS: We examined the changes in miRNAs regulating the atrial ion-channel proteins across the whole genome. We compared findings from 90 AF patients with those from 90 healthy subjects before RFA and three months after RFA. RESULT: Twenty-one miRNAs regulating ion-channel proteins were differentially expressed more than ten-fold, and the findings were completely reversed after RFA as compared with the pre-RFA results. The colonial regulating effects of miRNAs regulating the outward K+ current channels such as those for the ultra-rapid delayed rectifier potassium current (Ikur), voltage-dependent delayed rectifier potassium current (Ikr), and delayed rectifier potassium channel current (Iks) were more unanimous and stronger, while this was not the case for miRNAs regulating the L-type Ca2+ current and INa current channels. Generally, miR-1266 levels were increased in the blood but down-regulated in the rheumatic atrial tissue, while a dual luciferase test indicated that SCN5A was the direct target gene of miR-1266. CONCLUSION: Using RFA to treat AF may have an impact via reversing the changes in miRNAs regulating the ion-channel proteins, especially for outward K+ current channels such as Ikur, Ikr, and Iks, which may play a major role in electrical remodeling in AF. It may be that miR-1266 is an antiarrhythmic miRNA and an AF intervention target in the future (Tab. 2, Fig. 4, Ref. 46).


Assuntos
Fibrilação Atrial , MicroRNAs , Ablação por Radiofrequência , Antiarrítmicos , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/genética , Fibrilação Atrial/cirurgia , Átrios do Coração , Humanos , MicroRNAs/genética
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