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1.
Vet Microbiol ; 246: 108747, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32605760

RESUMO

H9N2 avian influenza viruses (AIVs) can cross species barriers and expand from birds tomammals and humans. It usually leads to economic loss for breeding farms and poses a serious threat to human health.This study investigated the molecular characteristics of H9N2 AIV isolated from a racing pigeon and its pathogenesis in BALB/c mice and pigeons. Phylogenetic analysis indicated that the H9N2 virus belonged to the Ck/BJ/94-like lineage, and acquired multiple specific amino acid substitutions that might contribute to viral transmission from birds to mammals and humans. A pathogenesis study showed that both mice and pigeons infected with H9N2 virus showed clinical signs and mortality. The H9N2 viruses efficiently replicated in mice and pigeons. In our study, high levels of viral shedding were detected in pigeons, but the infection was not transmitted to co-housed pigeons. Histopathological examination revealed the presence of inflammatory responses in the infected mice and pigeons. Immunohistochemical analysis showed the presence of H9N2 virus in multiple organs of the infected mice and pigeons. Moreover, the infected mice and pigeons demonstrated significant cytokine/chemokine production. Our results showed that the H9N2 virus can infect mice and pigeons, and can not be transmitted between pigeons through direct contact.

2.
ACS Sens ; 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32608228

RESUMO

A novel combination of surface plasmon resonance (SPR) and weak value amplification (WVA) is employed to measure the optical rotation angle and refractive index of chiral enantiomers such as sugars and amino acids. An extremely low optical rotation change (2.73×10-4 rad) is readily measurable, with a resolution of 6.75×10-7 rad, one order of magnitude higher than those obtained using weak value amplification with intensity modulation; and a refractive index change of 1.13×10-6 RIU is also detected, with a resolution of 1.99×10-9 RIU, a nearly one order of magnitude increase in sensitivity over weak measurement based on a Mach-Zehnder interferometer. The optical activity and refractive index change of chiral molecules are determined in real time by measurement of the output light intensity variation, whereby the absolute configuration of the chiral molecule is identified through the relation between intensity and molecular orientation. The combination of SPR-WVA sensing scheme fills a gap of capability for detecting optical activity of a molecular solution, which has not been possible with conventional SPR alone.

3.
Exp Eye Res ; : 108119, 2020 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-32603658

RESUMO

Myofibroblast transformation of human Tenon's fibroblasts severely challenges the outcome of glaucoma filtration surgery. epigallocatechin-3-gallate (EGCG) is considered as a potential reagent to overcome this issue for its anti-fibrosis effect on various human diseases, but it is unclear on the fibrosis of Tenon's fibroblasts. This study was conducted to investigate the effect of EGCG on TGF-ß1-induced myofibroblast transformation of human Tenon's fibroblasts. The human Tenon's fibroblasts were incubated in the medium containing 10 ng/mL TGF-ß1, and subsequently treated with EGCG or mitomycin C (MMC). The cell proliferation and migration were analyzed. The expression of alpha-smooth muscle actin (α-SMA), type I collagen (Col-I), and p-Smad2/3 were also evaluated. It showed that EGCG and MMC strongly inhibited the elevation in cell number in tissue explants compared to the tissues treated with TGF-ß1 alone. Scratch-Wound assay showed that 48 h after TGF-ß1 induction, only 10% of the wound width remained. But cells treated with EGCG still showed over 93% wound width. Further, EGCG effectively inhibited TGF-ß1-induced expression of α-SMA and Col-I as well as phosphorylation of Smad2/3 in Tenon's fibroblasts. Altogether, we concluded that EGCG suppressed the myofibroblast transformation in Tenon's fibroblasts through inactivating TGF-ß1/Smad signaling. These findings demonstrate that EGCG can be considered as one of the possible antifibrotic reagents for preventing postoperative scarring in glaucoma filtration surgery.

4.
Sci Total Environ ; 741: 140341, 2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-32615428

RESUMO

The frequent harmful algae blooms (HABs) in eutrophic waters pose serious threats to the water environment and health of human beings and animals. In this study, a new type of photocatalytic coating was prepared by loading Ag2CO3-N:GO (AGON) on the polyurethane sponge modified by silica sol via a dip coating method for the photocatalytic inactivation of Microcystis aeruginosa (M. aeruginosa) and degradation of Microcystin-LR (MC-LR). The factors including photocatalyst loading dosage, natural organic matter (NOM), and alkalinity were studied. The effects on the physiological characteristics of M. aeruginosa and reactive oxygen species (ROS) were also investigated to reveal the photocatalytic inactivation mechanisms. The results showed that the AGON coating-4 (the initial concentration of AGON suspension used for loading is 4 g/L) exhibited the optimum photocatalytic performance under visible light, which can completely remove chlorophyll a after 5 h of irradiation. And the NOM and alkalinity in water have relatively negative effects on the photocatalytic inactivation of algae. The prepared AGON coating also exhibited excellent photocatalytic performance in the degradation of MC-LR under visible light. It only needed 20, 60 and 120 min to completely degrade 0.1, 0.3 and 0.5 mg/L MC-LR, respectively. However, the mixed systems of algae and MC-LR required a longer time to achieve photocatalytic degradation. The O2- were the predominant reactive oxygen species, causing the damage of cell membranes and walls and the leakage of cellular content, which eventually led to the irreversible damage to algal cells. What's more, the coating can be reused several times due to its good cyclability and stability. Therefore, the AGON coating has promising prospects for the treatment of algal blooms in eutrophic waters.

5.
Immunity ; 2020 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-32579887

RESUMO

Granulocyte-monocyte progenitors (GMPs) have been previously defined for their potential to generate various myeloid progenies such as neutrophils and monocytes. Although studies have proposed lineage heterogeneity within GMPs, it is unclear if committed progenitors already exist among these progenitors and how they may behave differently during inflammation. By combining single-cell transcriptomic and proteomic analyses, we identified the early committed progenitor within the GMPs responsible for the strict production of neutrophils, which we designate as proNeu1. Our dissection of the GMP hierarchy led us to further identify a previously unknown intermediate proNeu2 population. Similar populations could be detected in human samples. proNeu1s, but not proNeu2s, selectively expanded during the early phase of sepsis at the expense of monocytes. Collectively, our findings help shape the neutrophil maturation trajectory roadmap and challenge the current definition of GMPs.

6.
BMC Med Imaging ; 20(1): 70, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32576224

RESUMO

BACKGROUND: We aimed to describe the chest CT findings in sixty-seven patients infected by Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). METHODS: We retrospectively reviewed 67 patients hospitalized in Ruian People's Hospital. All the patients received the positive diagnosis of SARS-CoV-2 infection. The CT and clinical data were collected between January 23rd, 2020 and February 10th, 2020. The CT images were analyzed by the senior radiologists. RESULTS: There are 54 patients with positive CT findings and 13 patients with negative CT findings. The typical CT findings in hospitalized patients with SARS-CoV-2 infection were ground glass opacities (42/54), lesions located in the peripheral area (50/54), multiple lesions (46/54), and lesions located in the lower lobes (42/54). There were less typical CT findings, including air bronchogram (18/54), pleural thickening or pleural effusion (14/54), consolidation (12/54), lesions in the upper lobes (12/54), interlobular septal thickening (11/54), reversed halo sign (9/54), single lesion (8/54), air cavities (4/54), bronchial wall thickening (3/54), and intrathoracic lymph node enlargement (2/54). CONCLUSIONS: CT features can play an important role in the early diagnosis and follow-up of COVID-19 patients.


Assuntos
Infecções por Coronavirus/diagnóstico por imagem , Pneumonia Viral/diagnóstico por imagem , Radiografia Torácica/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Betacoronavirus , China/epidemiologia , Infecções por Coronavirus/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/epidemiologia , Estudos Retrospectivos
7.
Artigo em Inglês | MEDLINE | ID: mdl-32599159

RESUMO

OBJECTIVES: To investigate the clinical and epidemiological characteristics of pediatric patients with Coronavirus disease-19 (COVID-19). METHODS: Pediatric patients diagnosed with COVID-19 from January 15 to March 15, 2020, from seven hospitals in Zhejiang Province were collected retrospectively and analyzed. RESULTS: Thirty-two children with COVID-19, ranging from 3 months to 18 years old, were enrolled. Family aggregation occurred in 87.5% of infant and preschool-aged children (7/8), and also school-aged children (14/16), but only 12.5% (1/8) of adolescents (p<0. 05, p<0.001). Most of these patients had mild symptoms, mainly fever (20/32), followed by cough (10/32) and fatigue (4/32). The average duration of viral RNA in respiratory samples and gastrointestinal samples were 15.8 d and 28.9 d, respectively. Detox duration in feces decreased with age, namely 39.8 d, 27.5 d and 20.4 d in infant and preschool children, school children and adolescents respectively (p0-6, -18<0. 01, p0-6, -14<0. 05). Pneumonia was found in 14 children, without any statistical significance in the incidence of pneumonia between different age groups. Thirty patients were treated with antiviral drugs and all patients were stable and gradually improved after admission. CONCLUSIONS: Most children with COVID-19 had a mild process and good prognosis. More attention should be paid to household contact history investigation in the diagnosis of COVID-19 in young children. Viral RNA lasts longer in gastrointestinal system than the respiratory tract, especially in younger children.

8.
Cancers (Basel) ; 12(6)2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32532053

RESUMO

Autophagy inhibition has been proposed to be a potential therapeutic strategy for cancer, however, few autophagy inhibitors have been developed. Recent studies have indicated that lysosome and autophagy related 4B cysteine peptidase (ATG4B) are two promising targets in autophagy for cancer therapy. Although some inhibitors of either lysosome or ATG4B were reported, there are limitations in the use of these single target compounds. Considering multi-functional drugs have advantages, such as high efficacy and low toxicity, we first screened and validated a batch of compounds designed and synthesized in our laboratory by combining the screening method of ATG4B inhibitors and the identification method of lysosome inhibitors. ATG4B activity was effectively inhibited in vitro. Moreover, 163N inhibited autophagic flux and caused the accumulation of autolysosomes. Further studies demonstrated that 163N could not affect the autophagosome-lysosome fusion but could cause lysosome dysfunction. In addition, 163N diminished tumor cell viability and impaired the development of colorectal cancer in vivo. The current study findings indicate that the dual effect inhibitor 163N offers an attractive new anti-cancer drug and compounds having a combination of lysosome inhibition and ATG4B inhibition are a promising therapeutic strategy for colorectal cancer therapy.

9.
Cardiovasc Diabetol ; 19(1): 80, 2020 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-32534586

RESUMO

BACKGROUND: The triglyceride-glucose index (TyG index) has been regarded as a reliable alternative marker of insulin resistance and an independent predictor of cardiovascular outcomes. Whether the TyG index predicts adverse cardiovascular events in patients with diabetes and acute coronary syndrome (ACS) remains uncertain. The aim of this study was to investigate the prognostic value of the TyG index in patients with diabetes and ACS. METHODS: A total of 2531 consecutive patients with diabetes who underwent coronary angiography for ACS were enrolled in this study. Patients were divided into tertiles according to their TyG index. The primary outcomes included the occurrence of major adverse cardiovascular events (MACEs), defined as all-cause death, non-fatal myocardial infarction and non-fatal stroke. The TyG index was calculated as the ln (fasting triglyceride level [mg/dL] × fasting glucose level [mg/dL]/2). RESULTS: The incidence of MACE increased with TyG index tertiles at a 3-year follow-up. The Kaplan-Meier curves showed significant differences in event-free survival rates among TyG index tertiles (P = 0.005). Multivariate Cox hazards regression analysis revealed that the TyG index was an independent predictor of MACE (95% CI 1.201-1.746; P < 0.001). The optimal TyG index cut-off for predicting MACE was 9.323 (sensitivity 46.0%; specificity 63.6%; area under the curve 0.560; P = 0.001). Furthermore, adding the TyG index to the prognostic model for MACE improved the C-statistic value (P = 0.010), the integrated discrimination improvement value (P = 0.001) and the net reclassification improvement value (P = 0.019). CONCLUSIONS: The TyG index predicts future MACE in patients with diabetes and ACS independently of known cardiovascular risk factors, suggesting that the TyG index may be a useful marker for risk stratification and prognosis in patients with diabetes and ACS.

10.
J Am Chem Soc ; 2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32520550

RESUMO

We present a theoretical design of the singlet-fission (SF) interconversion between two hydrogen tautomers to attract attention to electronic devices such as switches in the SF field. We develop a tuned π-electron conjugation strategy based on single-hydrogen migration to introduce diradical character and yield low-lying E(T1) levels. Specifically, these objectives could be accomplished by moving one hydrogen from a dihydrogen-substituted pyrazine-fused ring to another unsubstituted pyrazine-fused ring in tetraazatetracenes. The predicted SF efficiency would be expected to exceed 120%. To guide future SF design development, one rule of thumb regarding the S0-state and T1-state emerges from our research: In the S0-state, single-hydrogen migration is crucial for effectively localized electrons, which are the key factor in the formation of diradicals. Conversely, single-hydrogen migration induces a large area of π-electron conjugation in the T1-state, which is completely applied to the electron-hole interaction in the S0 → T1 transition, thereby providing low-lying E(T1) levels. Furthermore, a series of hydrogen tautomers of tetraazaacenes have been proposed as diradicaloid SF switches to verify the reliability of the above rule of thumb. This study will not only help researchers in the photovoltaic field to obtain the desired E(T1) in the future but also broaden the application of hydrogen migration in photovoltaic switch research and supplement the SF database.

11.
J Int Med Res ; 48(6): 300060520926349, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32529863

RESUMO

OBJECTIVE: Statins have been shown to be beneficial for the prevention of cardiovascular events. In elderly individuals, the efficacy of statins remains controversial and the comparative effect of statins has not been assessed. METHODS: MEDLINE, Embase, and the Cochrane Central database were searched for randomized controlled trials that assessed statins in older patients. RESULTS: Seventeen trials were analyzed. When used for secondary prevention, statins were associated with reduced risk of cardiovascular events, all-cause mortality, cardiovascular mortality, revascularization, and stroke. When used for primary prevention, statins reduced the risk of myocardial infarction and revascularization, but did not significantly affect other outcomes. A modest difference between pharmaceutical statin products was found, and high-quality evidence indicated that intensive atorvastatin had the greatest benefits for secondary prevention. CONCLUSIONS: In secondary prevention, evidence strongly suggests that statins are associated with a reduction in the risk of all-cause mortality, cardiovascular events, cardiovascular mortality, and revascularization. However, differences in the effects of various statins do not appear to have significant effects on therapy in secondary prevention for the elderly.

12.
J Int Med Res ; 48(6): 300060520920426, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32529868

RESUMO

OBJECTIVE: Measurement of positive end-expiratory pressure (PEEP)-induced recruitment lung volume using passive spirometry is based on the assumption that the functional residual capacity (FRC) is not modified by the PEEP changes. We aimed to investigate the influence of PEEP on FRC in different models of acute respiratory distress syndrome (ARDS). METHODS: A randomized crossover study was performed in 12 pigs. Pulmonary (n = 6) and extra-pulmonary (n = 6) ARDS models were established using an alveolar instillation of hydrochloric acid and a right atrium injection of oleic acid, respectively. Low (5 cmH2O) and high (15 cmH2O) PEEP were randomly applied in each animal. FRC and recruitment volume were determined using the nitrogen wash-in/wash-out technique and release maneuver. RESULTS: FRC was not significantly different between the two PEEP levels in either pulmonary ARDS (299 ± 92 mL and 309 ± 130 mL at 5 and 15 cmH2O, respectively) or extra-pulmonary ARDS (305 ± 143 mL and 328 ± 197 mL at 5 and 15 cmH2O, respectively). The recruitment volume was not significantly different between the two models (pulmonary, 341 ± 100 mL; extra-pulmonary, 351 ± 170 mL). CONCLUSIONS: PEEP did not influence FRC in either the pulmonary or extra-pulmonary ARDS pig model.

13.
J Appl Microbiol ; 2020 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-32500649

RESUMO

AIM OF THE STUDY: Effect of internalized phthalyl starch nanoparticles (PSNs) on the antimicrobial ability of Lactococcus lactis (LL) KCTC 2013. METHODS AND RESULTS: Phthalyl starch nanoparticles (PSNs) were prepared by self-assembly of phthalyl starch and the amount of the hydrophobic phthalic moieties were characterized by nuclear magnetic resonance (NMR), PSN1 (DS: 14.3 mol.-%), PSN2 (DS: 17.8 mol.-%) and PSN3 (DS: 30.4 mol.-%), the sizes of PSN1, PSN2, and PSN3 measured by dynamic light scattering (DLS) were 364.7, 248,4 and 213.4 nm respectively, the surface charges of PSNs measured by electrophoretic light scattering (ELS) were negative charges and according to scanning electron microscope (SEM) PSNs looked as spherical shapes. It was found that when PSNs were treated to LL, the PSNs were internalized into LL through nanoparticle size-, energy-, and glucose transporter-dependent mechanisms. The internalization was confirmed by confocal laser scanning microscopy (CLSM) and fluorescence-activated cell sorting (FACS). Nisin was isolated and identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Also, more nisin was produced from PSNs-treated LL than untreated- or starch-treated LL. Co-culture assay and agar diffusion test were performed to test the antimicrobial ability. Antimicrobial ability against Gram-negative Escherichia coli k88, Salmonella gallinarum and Gram-positive Listeria monocytogenes of LL treated with PSNs was higher than that of untreated or starch-treated group. Finally, it was found that the expression level of stress response genes dnaK, dnaJ and groES were significantly higher in PSNs-treated groups compared with starch-treated group or LL alone CONCLUSION: The internalization of PSNs into LL enhanced the production of nisin through mild intracellular stimulation, resulting in enhanced antimicrobial ability. SIGNIFICANCE AND IMPACT OF STUDY: This study shows the promising potential of PSNs as new prebiotics for increasing the production of nisin, thus demonstrating a new method for the biological production of such antimicrobial peptides.

14.
Zhongguo Gu Shang ; 33(6): 498-504, 2020 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-32573151

RESUMO

OBJECTIVE: To introduce the technical key points of lumbar annulus fibrosus suture under full-endoscope and analyze the clinical efficacy of full-endoscopic lumbar discectomy and annulus fibrosus suture. METHODS: A total of 50 patients with non contained lumbar disc herniation treated with full-endoscopic lumbar discectomy and annulus fibrosus suture in our department between January 2018 and November 2018 were included. Full-endoscopic single-stitch suture through transforaminal approach or double-stitch suture through interlaminar approach was selected according to lesion level. The lumbar MRI and CT were reexamined on the second day and 3 months after surgery to evaluate the completeness of the discectomy and the adequacy of nerve decompression respectively. The patients were followed up on the second day, 3 months, 6 months, and 1 year after surgery for pain relief using visual analogue scale (VAS, 100 -point scale). The patients were followed up at 3 months, 6 months, and 1 year postoperatively for the recovery of lumbar spine function using Oswestry Disability Index(ODI). At the 1-year follow-up, the Macnab standard of lumbar spine function was evaluated, and the recovery of nerve root function (sensory, muscular and reflex) was recorded. RESULTS: All operations were successfully completed, of which 27 patients were treated with transforaminal approach(including 8 cases of L3, 4 and 19 cases of L4, 5), and 23 patients(including 11 cases of L4, 5 and 12 cases of L5S1) with interlaminar approach. The average operation time was 43.2 minutes. There were no surgical complications and no recurrence of lumbar disc herniation. Postoperative lumbar MRI and CT examinations of all patients showed that the herniated disc was completely removed and the nerveswere fully decompressed. All patients had significant relief of low back pain and lower extremity radiation pain, and the ODI score improved significantly(P<0.01). At 1 year postoperative follow up, 17 patients got an excellent result, 29 good and 4 fair according to Macnab evaluation system. On the first year after surgery, the sense of damaged nerve roots and muscle strength were significantly restored (P<0.01), but tendon reflexes were not significantly restored (P>0.05). CONCLUSION: Full-endoscopic lumbar discectomy and annulus fibrosus suture are safe and effective techniques for minimally invasive spinal surgery, which can reduce the recurrence rate of lumbar disc herniation after full endoscopic lumbar discectomy.

15.
PLoS One ; 15(6): e0233903, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32516316

RESUMO

OBJECTIVE: Transcranial direct-current stimulation (tDCS) is a noninvasive approach that can alter brain excitability. Several studies have shown the effectiveness of tDCS in improving language and movement function in stroke patients. However, the effect of tDCS on cognitive function after stroke remains uncertain. METHODS: We searched Medline, Embase, the Cochrane Central Register of Controlled Trials (CENTRAL), the China National Knowledge Infrastructure, the China Science and Technology Journal Database, and the Wanfang Data Knowledge Service Platform from inception to April 2, 2019. Two reviewers independently screened the studies, extracted the data, and evaluated the quality of the included studies using the Cochrane Collaboration Risk of Bias Tool. All statistical analyses were performed in RevMan 5.3, and the mean difference (MD) or standard mean difference (SMD) were used as the pooled statistics. RESULTS: Fifteen studies involving 820 participants were included. When compared with passive tDCS, anodal tDCS was associated with improved general cognitive performance as examined by the Minimum Mental State Examination or Montreal Cognitive Assessment (SMD = 1.31, 95% CI 0.91-1.71, P < 0.00001), attention performance (SMD = 0.66, 95% CI 0.11-1.20, P = 0.02). There was no significant difference in memory performance (SMD = 0.41, 95% CI -0.67-1.50, P = 0.46). CONCLUSIONS: tDCS is likely to be effective for patients with cognitive impairment after stroke. The evidence for different effects based on population characteristics and stimulation methods was limited, but a real effect cannot be ruled out. More high-quality research in this field is required to determine the potential benefits of tDCS in the treatment of cognitive deficits after stroke and to establish the optimal treatment program.

16.
Ying Yong Sheng Tai Xue Bao ; 31(5): 1587-1598, 2020 May.
Artigo em Chinês | MEDLINE | ID: mdl-32530237

RESUMO

An indoor rainfall simulation experiment was conducted to examine the hydrodynamic characteristics, erosion characteristics, and erosion dynamics mechanisms of earth (excluding gra-vel) and earth-rock (gravel mass fraction 30%) Lou soil engineering accumulation in the Loess area across different rainfall intensities and slope gradients. Results showed that the presence of gravel changed the hydrodynamic characteristics of the engineering accumulation slope. The flow velocity, froude number, unit stream power, and unit energy of water-carrying section of the earth-rock slope were 1.7%-49.7%, 6.7%-60.6%, 2.0%-44.6% and 1.0%-26.7% lower than those of the earth slope, while the Manning roughness coefficient and runoff shear stress of the earth-rock slope were 6.2%-169.4% and 5.7%-79.3% higher than those of the earth slope respectively. Under the intensity of 2.0 and 2.5 mm·min-1, erosion rate of the earth-rock slope was 26.2%-89.9% lower than that of earth slope. The gravel significantly reduced slope erosion of the Lou soil engineering accumulation. Erosion rate and hydrodynamic parameters of the two accumulations were linearly related. The erodibility parameters of earth-rock slope were 56.1%-73.3% lower than that of earth slope. In the critical hydrodynamic parameters, runoff shear stress of earth-rock slope was 11.1% higher, while the stream power, unit stream power and unit energy of water-carrying section were 25.4%, 64.0% and 5.0% lower than those of the earth slope, respectively. The existence of gravel controlled rainfall erosion process on the slope of the engineering accumulation to some extent.


Assuntos
Chuva , Solo , China , Sedimentos Geológicos , Água , Movimentos da Água
17.
Clin Nutr ; 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32536583
18.
J Invest Dermatol ; 140(7): 1305-1314.e1, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32571496

RESUMO

Skin histology is traditionally carried out using two-dimensional tissue sections, which allows for rapid staining, but these sections cannot accurately represent three-dimensional structures in skin such as nerves, vasculature, hair follicles, and sebaceous glands. Although it may be ideal to image skin in a three-dimensional manner, it is technically challenging to image deep into tissue because of light scattering from collagen fibrils in the dermis and refractive index mismatch owing to the presence of differing biological materials such as cytoplasm, and lipids in the skin. Different optical clearing methods have been developed recently, making it possible to render tissues transparent using different approaches. Here, we discuss the steps involved in tissue preparation for three-dimensional volumetric imaging and provide a brief overview of the different optical clearing methods as well as different imaging modalities for three-dimensional imaging.

19.
Urology ; 2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32593627

RESUMO

OBJECTIVE: To evaluate and compare the surgical outcomes and complications of the modified circumcision using disposable circumcision suture device (device group) and the conventional dorsal slit circumcision (conventional group) in children. METHODS: A total of 284 patients were randomized to either device group or conventional group. All patients were preoperatively assessed and evaluated at 4 weeks after surgery. The perioperative data and postoperative outcomes were compared between the two groups. RESULTS: No statistical differences were observed in the average age and indications between the two groups preoperatively (p>0.05). Compared with the conventional group, patients in the device group were shorter mean operative time, less blood loss, lower intraoperative and postoperative pain score, faster incision healing time and a higher satisfaction rate of penile cosmetic appearance (p<0.01). Similarly, the incidences of complication were significantly lower in the device group than in the conventional group (4.3% vs 12.3%, p<0.05). CONCLUSIONS: The modified circumcision using disposable circumcision suture device is a simple, safe, faster, and effective procedure and may become the attractive alternative to the conventional technique for the children, with a relatively lower complication rate and better cosmetic results. With the improvement of disposable circumcision suture device, the modified circumcision using disposable circumcision suture device has the potential to be widely used in the world.

20.
Artigo em Inglês | MEDLINE | ID: mdl-32539324

RESUMO

The resistive switching behavior in resistive random access memories (RRAMs) using atomic-layer-deposited Ga2O3/ZnO composite film as the dielectric was investigated. By alternatively atomic-layer-depositing Ga2O3 and ZnO with different thickness, we can accurately control the oxygen vacancy concentration. When regulating ZnO to ∼31%, the RRAMs exhibit a forming-free property as well as outstanding performance, including the ratio of a high resistance state to the low resistance state of 1000, retention time of more than 1 × 104 s, and the endurance of 100. By preparing RRAMs of different Zn concentration, we carried out a comparative study and explored the physical origin for the forming-free property as well as good performance. Finally, a unified model is proposed to account for the resistive switching and the current conduction mechanism, providing meaningful insights in the development of high-quality and forming-free RRAMs for future memory and neuromorphic applications.

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