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1.
World J Surg Oncol ; 18(1): 259, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33004051

RESUMO

BACKGROUND: Splenic marginal zone lymphoma (SMZL) is a rare non-Hodgkin lymphoma, and much little is known about its clinical characteristics and management strategies. Here we present a case of SMZL and review relevant literature to provide a better recognition of this disease entity. CASE PRESENTATION: A 49-year-old Chinese female was admitted to our hospital with complaints of abdominal distension and acid reflux. Physical examinations and imaging investigations suggested the presence of splenomegaly. Laboratory workups revealed mildly reduced white blood cell count otherwise was not remarkable. The patient underwent splenectomy. Histological examination combined with immunohistochemical analysis of the resected spleen confirmed the diagnosis of SMZL. The patient recovered uneventfully during follow-ups. CONCLUSIONS: Due to the rarity and unspecific clinical features, SMZL is extremely challenging to be diagnosed preoperatively. Patients with SMZL are generally associated with favorable prognosis. Combining the staging characteristics of non-Hodgkin's lymphoma and splenic primary lymphoma may assist in clinical staging management of SMZL.

2.
Artigo em Inglês | MEDLINE | ID: mdl-33023167

RESUMO

Solute storage and release in groundwater are key processes in solute transport for groundwater remediation and protection. In karst areas where concentrated recharge conditions exist, pollution incidents can easily occur in springs that are hydraulically connected to densely inhabited karst depressions. The intrinsic heterogeneity common in karst media makes modeling solute transport very difficult with great uncertainty. Meanwhile, it is noteworthy that solute storage and release within subsurface conduits and fissures exhibit strong controlling function on pollutant attenuation during underground floods. Consequently, in this paper, we identified and estimated the solute storage and release processes in karst water systems under concentrated recharge conditions. The methodology uses the advection-dispersion method and field tracer tests to characterize solute transport in different flow paths. Two solute transport pathways were established (i.e., linear pathway (direct transport through karst conduits) and dynamic pathway (flow through fissures)). Advection-dispersion equations were used to fit the breakthrough curves in conduit flow, while the volume of solute storage in fissures were calculated by segmenting the best fitting curves from the total breakthrough curves. The results show that, greater recharge flow or stronger dynamic conditions leads to lower solute storage rate, with the storage rate values less than 10% at high water level conditions. In addition, longer residence time was recorded for solute exchange between conduits and fissures at the low water level condition, thereby contributing to a higher solute storage rate of 26% in the dynamic pathway.

3.
Theranostics ; 10(25): 11622-11636, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33052237

RESUMO

Rationale: Constitutive activation of the NF-κB signalling pathway plays a pivotal role in the pathogenesis of activated B cell-like diffuse large B-cell lymphomas (ABC-DLBCLs), the most aggressive and chemoresistant form of DLBCL. In ABC-DLBCLs, the CARMA1-BCL10 (CB) complex forms a filamentous structure and functions as a supramolecular organizing centre (CB-SMOC) that is required for constitutive NF-κB activation, making it an attractive drug target for ABC-DLBCL treatment. However, a pharmaceutical approach targeting CB-SMOC has been lacking. Here, we developed Bcl10 peptide inhibitors (BPIs) that specifically target the BCL10 filamentation process. Methods: Electron microscopy and immunofluorescence imaging were used to visualize the effect of the BPIs on the BCL10 filamentation process. The cytotoxicity of the tested BPIs was evaluated in DLBCL cell lines according to cell proliferation assays. Different in vitro experiments (pharmacokinetics, immunoprecipitation, western blotting, annexin V and PI staining) were conducted to determine the functional mechanisms of the BPIs. The in vivo therapeutic effect of the BPIs was examined in different xenograft DLBCL mouse models. Finally, Ki67 and TUNEL staining and histopathology analysis were used to evaluate the antineoplastic mechanisms and systemic toxicity of the BPIs. Results: We showed that these BPIs can effectively disrupt the BCL10 filamentation process, destabilize BCL10 and suppress NF-κB signalling in ABC-DLBCL cells. By examining a panel of DLBCL cell lines, we found that these BPIs selectively repressed the growth of CB-SMOC-dependent DLBCL cells by inducing apoptosis and cell cycle arrest. Moreover, by converting the BPIs to acquire a D-retro inverso (DRI) configuration, we developed DRI-BPIs with significantly improved intracellular stability and unimpaired BPI activity. These DRI-BPIs selectively repressed the growth of CB-SMOC-dependent DLBCL tumors in mouse xenograft models without eliciting discernible adverse effects. Conclusion: We developed novel BPIs to target the BCL10 filamentation process and demonstrated that targeting BCL10 by BPIs is a potentially safe and effective pharmaceutical approach for the treatment of ABC-DLBCL and other CB-SMOC-dependent malignancies.

4.
Int J Mol Sci ; 21(20)2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33053775

RESUMO

OBJECTIVE: Pannexin-1 (Panx1) is suspected of having a critical role in modulating neuronal excitability and acute neurological insults. Herein, we assess the changes in behavioral and electrophysiological markers of excitability associated with Panx1 via three distinct models of epilepsy. Methods Control and Panx1 knockout C57Bl/6 mice of both sexes were monitored for their behavioral and electrographic responses to seizure-generating stimuli in three epilepsy models-(1) systemic injection of pentylenetetrazol, (2) acute electrical kindling of the hippocampus and (3) neocortical slice exposure to 4-aminopyridine. Phase-amplitude cross-frequency coupling was used to assess changes in an epileptogenic state resulting from Panx1 deletion. RESULTS: Seizure activity was suppressed in Panx1 knockouts and by application of Panx1 channel blockers, Brilliant Blue-FCF and probenecid, across all epilepsy models. In response to pentylenetetrazol, WT mice spent a greater proportion of time experiencing severe (stage 6) seizures as compared to Panx1-deficient mice. Following electrical stimulation of the hippocampal CA3 region, Panx1 knockouts had significantly shorter evoked afterdischarges and were resistant to kindling. In response to 4-aminopyridine, neocortical field recordings in slices of Panx1 knockout mice showed reduced instances of electrographic seizure-like events. Cross-frequency coupling analysis of these field potentials highlighted a reduced coupling of excitatory delta-gamma and delta-HF rhythms in the Panx1 knockout. SIGNIFICANCE: These results suggest that Panx1 plays a pivotal role in maintaining neuronal hyperexcitability in epilepsy models and that genetic or pharmacological targeting of Panx1 has anti-convulsant effects.

5.
J Craniofac Surg ; 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-33003160

RESUMO

OBJECTIVE: This study aimed to improve the accuracy and efficacy of the keyhole transsylvian approach to remove hypertensive basal ganglia hemorrhage. The authors presented a stable keyhole craniotomy based on anterior squamous suture to expose insular cortex and basal ganglia. METHODS: Twenty-nine patients with hypertensive basal ganglia hemorrhage were treated with keyhole surgery and studied in Guangdong sanjiu brain hospital. RESULTS: By using a bone suture marked keyhole transsylvian approach, near-complete (90%) hematoma evacuation was achieved in 21 cases (72.4), 70% to 90% in 8 cases (24.1), and less than 70% in 1 case (3.4%). In our cohort, 55.1% (16/29) with good function (GOS score 4-5), 41.3% (12/29) with disability (GOS score 3), and 3.4% (1/29) in a vegetative state (GOS score 2). No patients died within 6 months of operation. CONCLUSIONS: Our method can greatly minimize the bone exposure and precisely located the distal Sylvian fissure. A stable keyhole craniotomy based on bone suture can be identically safe and effective in comparison with classic surgery, and it consumes less time and less intra-operative bleeding.

6.
Ann Palliat Med ; 2020 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-33040540

RESUMO

Aggressive angiomyxoma (AAM) is rare. AAM is characterized by invasion and recurrence. Improving the detection rate of AAM through ultrasonic inspection technology. There is very little literature reported on AAM. And the literature on the ultrasonic performance of AAM is rare. Therefore, this article describes the ultrasound manifestation of a 54-year-old woman whose pathology is confirmed to be AAM, and summarizes the common ultrasound manifestations of AAM. The unique feature is that the ultrasound performance does not explore the typical "vortex". So we need to diagnose this case through other ultrasound findings. The patient initially had no obvious cause of pain in the right hip. Transvaginal ultrasound examination of the pelvic was performed on the patient, and pathological sections were examined. The result suggested mesenchymal tumor. After surgical resection of the tumor, the pathology was again confirmed as AAM. The tumor is composed of well-differentiated spindle-shaped stellate cells with interstitial mucus degeneration, and vascular proliferation can be seen, which is consistent with deep AAM. Through this case we found that pathology is the gold standard for AAM, but early screening of AAM by ultrasound is feasible.

7.
Technol Cancer Res Treat ; 19: 1533033820960745, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33043809

RESUMO

BACKGROUND: To study the specific expression of circular RNA (circRNA) in breast cancer and adjacent normal tissues to identify differentially expressed circRNA in breast cancer patients. To study the correlation between circRNA and clinical data of breast cancer, and to evaluate its potential as a breast cancer biomarker. METHODS: The differential expression of circRNAs between the breast cancer tissues and adjacent normal tissues was screened by Human CircRNA Microarray. Candidate circRNAs verified by qRT-PCR. CircRNA was analyzed by Agilent GeneSpring 13.0 software. SPSS23.0, GraphPad Prism, and Sigmaplot software were used for statistical analysis. Perform T test, one-way ANOVA, curve regression analysis and ROC curve analysis for evaluating the diagnostic value of circular RNA. RESULTS: Among the 2021 differentially expressed circRNAs, 546 were up-regulated and 1475 were down-regulated in breast cancer tissues. The validation study demonstrated that six circRNAs were downregulated. Among them, hsa_circ_0104824 proved high correlation between breast cancer tissues and plasma samples in its expression and diagnostic value. CONCLUSION: Hsa_circ_0104824 may serve as a promising predictive biomarker and therapeutic target for patients with breast cancer.

8.
Artigo em Inglês | MEDLINE | ID: mdl-33037477

RESUMO

BACKGROUND: Primary spinal pilocytic astrocytoma (PA) is an extremely rare low-grade astrocytoma with unclear natural history. The demographic characteristics, imaging features, and long-term surgical outcomes have not been clarified due to low prevalence and limited reports. METHODS: A retrospective review within a single institution between 2004 and 2018 of all patients with pathologically proven PA was conducted. Patient data including demographics, radiographic features, treatment modalities, and long-term outcomes were evaluated. RESULTS: Twenty consecutive patients were identified, and 16 (80%) were male patients, with a mean age at presentation of 29 ± 13 years. The lesion was primarily located in cervical (n = 10, 50%), thoracic (n = 7, 35%), cervico-thoracic junction (n = 2), and lumbar level (n = 1, 5%). The tumor had a mean extension of 4 ± 2 (1-7) vertebral segments. Most PAs were located eccentrically (n = 16, 80%), with most being heterogeneous in appearance (cystic and solid) or purely cystic (n = 14, 70%), and had unclear margins (n = 16, 80%). Eleven patients (55%) had associated syringomyelia. Gross total resection (GTR) was achieved in 11 (55%) patients, and subtotal resection (STR) in 9 (45%). During a mean follow-up of 104 ± 56 months, 2 patients died and recurrence was found in 4 patients (20%), translating to a mean progression-free survival of 21 ± 11 months. CONCLUSION: Primary spinal PA is a rare entity with acceptable progression-free survival if treated appropriately. Surgical resection may provide reasonable prolongation of survival, and GTR should be achieved if possible. A close follow-up is recommended especially for residual lesions, and a further in-depth investigation of molecular biomarkers is needed to stratify risk and prognostic factors.

9.
Ann Transplant ; 25: e924282, 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33046687

RESUMO

BACKGROUND Alagille syndrome (AGS) is an autosomal dominant hereditary disorder characterized by identifiable abnormalities in the liver, heart, face, skeleton, and eyes. Recently, liver transplantation (LT) has been proposed as a therapeutic strategy for patients with AGS complicated by end-stage liver disease, but clinical experience in performing anesthesia in LT for AGS is still scarce. We aimed to summarize our preliminary experience in the anesthetic management of LT for AGS in this study. MATERIAL AND METHODS We reviewed the cases of 11 patients with AGS who underwent LT from September 2017 to April 2019. Preoperative multi-system comorbidities, intraoperative details, and postoperative outcomes were retrospectively collected and summarized. RESULTS Cardiopulmonary abnormalities were common (81.8%) in AGS patients before LT, and the most frequent comorbidity was pulmonary artery stenosis. After careful anesthetic evaluation and perioperative management, all patients survived during the perioperative period without significant cardiovascular complications. However, there was an unexpectedly high prevalence of surgical complications and re-operations in AGS patients compared to biliary atresia recipients (54.5% vs. 22.4%, P=0.031; and 45.5% vs. 15.3%, P=0.028, respectively). CONCLUSIONS Perioperative management of LT for AGS patients can be particularly challenging, requiring a full understanding of the pathophysiology, as well as a careful preoperative evaluation of the multi-system comorbidities. The high prevalence of postoperative surgical complications should be a matter of concern.

10.
FASEB J ; 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33047388

RESUMO

Locally produced in human granulosa cells of the developing follicle, bone morphogenetic protein 2 (BMP2) plays a crucial role in the regulation of ovarian folliculogenesis and luteal formation. Brain-derived neurotrophic factor (BDNF) is an intraovarian neurotrophic factor that has been shown to promote oocyte maturation and subsequent fertilization competency. At present, little is known regarding the intracellular regulation, assembly and secretion of endogenous BDNF in human granulosa cells. The aim of this study was to explore the effect of BMP2 on the expression and production of BDNF in human granulosa cells and the molecular mechanisms underlying this effect. An immortalized human granulosa cell line (SVOG) and primary human granulosa-lutein (hGL) cells were utilized as in vitro study models. Our results showed that BMP2 significantly increased the mRNA and secreted levels of BDNF. Additionally, BMP2 upregulated the expression of furin at the transcriptional and translational levels. Knockdown of endogenous furin partially attenuated the BMP2-induced increase in BDNF production, indicating that furin is involved in the maturation process of BDNF. Using pharmacological (kinase receptor inhibitors) and siRNA-mediated inhibition approaches, we demonstrated that BMP2-induced upregulation of BDNF and furin expression is most likely mediated by the activin receptor-like kinase (ALK)2/ALK3-SMAD4 signaling pathway. Notably, analysis using clinical samples revealed that there was a positive correlation between follicular fluid concentrations of BMP2 and those of BDNF. These results indicate that BMP2 increases the production of mature BDNF by upregulating the precursor BDNF and promoting the proteolytic processing of mature BDNF. Finally, we also investigated the effects of BMP2 on ovarian steroidogenesis and the results showed that BMP2 treatment significantly increased the accumulated level of estradiol (by upregulating the expression of FSH receptor and cytochrome P450 aromatase), whereas it decreased the accumulated level of progesterone (by downregulating the expression of LH receptors and steroidogenic acute regulatory protein) in primary hGL cells. Our findings provide a novel paracrine mechanism underlying the regulation of an intraovarian growth factor in human granulosa cells.

11.
Artigo em Inglês | MEDLINE | ID: mdl-33006892

RESUMO

Recently, electrochemical hydrogen peroxide (H2O2) generation from oxygen molecules has been extensively studied. Thus far, the best peroxide activity under alkaline conditions has been reported at the surface of a mild reduced graphene oxide annealed at 600 °C (mrGO-600). However, the detailed material information, such as chemical functionality and structural morphology, is unknown, which results in ambiguous debates on its catalytic active sites. To solve this problem, we intensively characterize the structure of mrGO-600 to clarify the origin of its catalytic activity. Various characterizations, including X-ray photoelectron spectroscopy, Raman spectroscopy, infrared spectroscopy, near-edge X-ray absorption fine spectroscopy, and high-resolution transmittance electron microscopy coupled with in situ infrared spectroelecrochemistry, reveal that the annealing process generates not only various hole edge defects that are related to the ring ether group but also numerous point defects that result in a small-sized disconnected graphitic carbon region. These defects are believed to form a unique atomic level configuration in mrGO-600, which enables it to facilitate high peroxide-generated activity from oxygen molecules in an alkaline electrolyte.

12.
Neurobiol Dis ; 146: 105118, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33031903

RESUMO

Fragile X syndrome (FXS), a neurodevelopmental disorder with autistic features, is caused by the loss of the fragile X mental retardation protein. Sex-specific differences in the clinical profile have been observed in FXS patients, but few studies have directly compared males and females in rodent models of FXS. To address this, we performed electroencephalography (EEG) recordings and a battery of autism-related behavioral tasks on juvenile and young adult Fmr1 knockout (KO) rats. EEG analysis demonstrated that compared to wild-type, male Fmr1 KO rats showed an increase in gamma frequency band power in the frontal cortex during the sleep-like immobile state, and both male and female KO rats failed to show an increase in delta frequency power in the sleep-like state, as observed in wild-type rats. Previous studies of EEG profiles in FXS subjects also reported abnormally increased gamma frequency band power, highlighting this parameter as a potential translatable biomarker. Both male and female Fmr1 KO rats displayed reduced exploratory behaviors in the center zone of the open field test, and increased distance travelled in an analysis of 24-h home cage activity, an effect that was more prominent during the nocturnal phase. Reduced wins against wild-type opponents in the tube test of social dominance was seen in both sexes. In contrast, increased repetitive behaviors in the wood chew test was observed in male but not female KO rats, while increased freezing in a fear conditioning test was observed only in the female KO rats. Our findings highlight sex differences between male and female Fmr1 KO rats, and indicate that the rat model of FXS could be a useful tool for the development of new therapeutics for treating this debilitating neurodevelopmental disorder.

13.
Sci Total Environ ; 755(Pt 1): 142548, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-33035977

RESUMO

Chinese caterpillar fungus (Ophiocordyceps sinensis) is a precious traditional medicine which is mostly distributed on the Qinghai-Tibetan Plateau (QTP). Due to its medicinal values, it has become one of the most valuable biological commodities and widely traded in recent years worldwide. However, its habitat has changed profoundly in recent years under global warming as well as anthropogenic pressures, resulting in a sharp decline in its wild population in recent years. Based on the occurrence samples, this paper estimates the potential distribution of caterpillar fungus using MaxEnt model. The model simulates potential geographical distribution of the species under current climate conditions, and examine future distributions under different climatic change scenarios (i.e., RCP 2.6, RCP 4.5, RCP 6.0 and RCP 8.5 have been modelled in 2050s and 2070s, respectively). For examining the impacts of climate change in future, the integrated effects of climatic impact, trading, and overexploitation had been analyzed in detailed routes. The results show that: 1) The distribution patterns of caterpillar fungus under scenario RCP 2.6 have been predicted without obvious changes. However, range shift has been observed with significant shrinks across all classes of suitable areas in Tianshan, Kunlun Mountains, and the southwestern QTP in 2050s and 2070s under RCP 4.5, RCP 6.0 and RCP 8.5 scenarios, respectively. 2) The exports were decreasing drastically in recent years. Guangzhou and Hongkong are two international super import and consumption centres of caterpillar fungus in the world. 3) Both ecological and economic sustainable utilization of the caterpillar fungus has been threatened by the combined pressures of climate change and overexploitation. A strict but effective regulation and protection system, even a systematic management plan not just on the collectors but the whole explore process are urgently needed and has to be issued in the QTP.

14.
J Affect Disord ; 279: 122-130, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33045554

RESUMO

BACKGROUND: The Low Resistance Thought Induction Psychotherapy (TIP) is a comprehensive psychological treatment which could improve the clinical symptoms of major depressive disorder (MDD). However, the neural mechanisms for TIP treating MDD still remain unclear. This study aimed to investigate the topology of intrinsic connectivity network and the therapeutic effects of TIP in MDD on these topological properties. METHODS: Longitudinal study was conducted in 20 first-episode, treatment-naive MDD patients at baseline and after 6 weeks (12 sessions) of TIP treatment based on resting-state functional magnetic resonance image (rsfMRI) in conjunction with graph theoretical analysis. We constructed functional connectivity matrices and extracted the attribute features of the small-world networks in both MDD and age-, education level-, and gender-matched healthy controls (HCs). The global and local small-world network properties were explored and compared between MDD at baseline and HCs. The therapeutic effect of TIP was examined by comparing alterations in global and local network properties between MDD at baseline and after treatment. RESULTS: At baseline, MDD showed altered small-worldness and aberrant nodal properties in the frontolimbic circuit particularly in the orbital frontal gyrus, insula, precuneus and middle cingulate gyrus as compared with HCs. Following 6 weeks treatment, the abnormalities in the small-worldness and the nodal metrics were modulated, which were accompanied by a significant improvement in the clinical symptoms. CONCLUSIONS: Our findings contributed to the understanding of the abnormal topological patterns in the frontolimbic systems in MDD and implicated that these disruptions may be modified by TIP treatment.

15.
Inorg Chem ; 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33054208

RESUMO

Dual-emitting and thermochromic manganese ion single doped ZnGa2-yAlyO4 phosphors were prepared by solid-state reaction. The regulation of the valence state and the luminescent properties, especially the luminescent thermal stability of manganese ions in ZnGa2-yAlyO4, are discussed in detail. When excited by ultraviolet (UV) light, the emission spectra of ZnGa2O4:Mn2+,Mn4+ present an ultranarrow green emission band at 503 nm with a fwhm of 22 nm, which derives from the Mn2+ ions formed by the self-reduction of doped Mn4+, and a red emission band of the Mn4+ ions at 669 nm. In addition, a ZnGa2-yAlyO4:Mn2+,Mn4+ solid solution was designed and synthesized by Al3+ replacing Ga3+. The doping of Al3+ effectively inhibited the degree of Mn4+ self-reduction to Mn2+, thus realizing the regulation of valence state of manganese ions. Interestingly, the thermal stability of luminescence shows that the response of Mn2+ and Mn4+ to temperature is obviously different in ZnGa2-yAlyO4, implying the potential of the prepared phosphors as optical thermometers. Subsequently, three kinds of optical thermometers with superior color discrimination and high relative sensitivity (Sr) based on the fluorescence intensity ratio (FIR) technique were realized in 100-475 K. The Sr value of ZGO:0.005Mn/ZGA0.5O:0.005Mn/ZGAO:0.005Mn phosphors can be as high as 4.345%/4.001%/3.488% K-1 (at 350/325/400 K), reflecting the great potential of ZnGa2O4:Mn2+,Mn4+ for optical thermometry applications.

17.
J Contam Hydrol ; 235: 103732, 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33069943

RESUMO

To better understand the origin of the saline groundwater in the Pearl River Delta (PRD), China, water samples were collected from local aquifers, rainfall regions and rivers for isotopic and hydrochemical analysis. The hydraulic connections between the aquifers in the study area were tested by analyzing a series of water samples from different months in one hydrological year (January 2017-January 2018). The total dissolved solids (TDS) results show that the highly saline groundwater only occurs in the granites, which indicates that the TDS distribution depends on the permeability of the aquifer material. Variations in the TDS and stable hydrogen and oxygen isotope ratios (δ2H and δ18O, respectively) of the water samples from different months reflect a dynamic balance among evaporation and precipitation in a hydrological year. Additionally, the very old radiocarbon (14C) ages and undetectable amounts of tritium (3H) in most of the groundwater samples suggest that the residence time of the groundwater in the aquifer is high. In general, the saline groundwater (TDS >5 g/L) in the area mainly originated primarily from seawater intrusion in the past. Meanwhile, the water contents of saline groundwater were affected by evaporation and long-term geochemical processes, such as water-rock, sulfate reduction, methanogenesis and ion exchange. The fresh groundwater in the area is from modern meteoric precipitation recharge.

18.
Sensors (Basel) ; 20(17)2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32887307

RESUMO

ZnO and carbon quantum dots (CQDs) were synthesized by a hydrothermal method, and CQDs were doped into ZnO by a grinding method to fabricate a ZnO/CQDs composite. The X-ray diffraction and the scanning electron microscope revealed that the as-prepared ZnO has a structure of wurtzite hexagonal ZnO and a morphology of a flower-like microsphere which can provide more surface areas to adsorbed gases. The ZnO/CQDs composite has a higher gas sensitivity response to NO gas than ZnO microspheres. A gas sensitivity test of the ZnO/CQDs composite showed that the sensor had a high NO response (238 for 100 ppm NO) and NO selectivity. The detection limit of the ZnO/CQDs composite to NO was 100 ppb and the response and recovery times were 34 and 36 s, respectively. The active functional group provided by CQDs has a significant effect on NO gas sensitivity, and the gas sensitivity mechanism of the ZnO/CQDs composite is discussed.

19.
Nanomaterials (Basel) ; 10(9)2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32887500

RESUMO

Single nanowires (NWs) are of great importance for optoelectronic applications, especially solar cells serving as powering nanoscale devices. However, weak off-resonant absorption can limit its light-harvesting capability. Here, we propose a single NW coated with the graded-index dual shells (DSNW). We demonstrate that, with appropriate thickness and refractive index of the inner shell, the DSNW exhibits significantly enhanced light trapping compared with the bare NW (BNW) and the NW only coated with the outer shell (OSNW) and the inner shell (ISNW), which can be attributed to the optimal off-resonant absorption mode profiles due to the improved coupling between the reemitted light of the transition modes of the leak mode resonances of the Si core and the nanofocusing light from the dual shells with the graded refractive index. We found that the light absorption can be engineered via tuning the thickness and the refractive index of the inner shell, the photocurrent density is significantly enhanced by 134% (56%, 12%) in comparison with that of the BNW (OSNW, ISNW). This work advances our understanding of how to improve off-resonant absorption by applying graded dual-shell design and provides a new choice for designing high-efficiency single NW photovoltaic devices.

20.
BMC Public Health ; 20(1): 1354, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32887583

RESUMO

BACKGROUND: Disparities in the utilization, expenditures, and quality of care by insurance types have been well documented. Such comparisons have yet to be investigated in end-of-life (EOL) settings in China, where public insurance covers over 95% of the Chinese population. This study examined the associations between health insurance and EOL care in the last six months of life: outpatient visits, emergency department (ED) visits, inpatient services, intensive care unit (ICU) admissions, expenditures, and place of death among the cancer patients. METHODS: A total of 398 patients diagnosed with cancer who survived more than 6 months after diagnosis and died from July 2015 to June 2017 in urban Yichang, China, were included. Descriptive analysis and multivariate regression models were used to investigate the bivariate and independent associations, respectively, between health insurance with EOL healthcare utilization, expenditures and place of death. RESULTS: Urban Employee Basic Medical Insurance (UEBMI) beneficiaries visited EDs more frequently than Urban Resident-based Basic Medical Insurance (URBMI) and New Rural Cooperative Medical Scheme (NRCMS) beneficiaries (marginal effects [95% Confidence Interval]: 2.15 [1.81-2.48] and 1.92 [1.59-2.26], respectively). NRCMS and UEBMI beneficiaries had more hospitalizations than URBMI beneficiaries (1.01 [0.38-1.64] and 0.71 [0.20-1.22], respectively). Compared to URBMI beneficiaries, NRCMS beneficiaries and UEBMI beneficiaries had ¥15,722 and ¥43,241 higher expenditures. Similarly, UEBMI beneficiaries were most likely to die in hospitals, followed by NRCMS (UEBMI vs. NRCMS: 0.23 [0.11-0.36]) and URBMI (UEBMI vs. URBMI: 0.67 [0.57-0.78]) beneficiaries. CONCLUSIONS: The disproportionately lower utilization of EOL care among NRCMS and URBMI beneficiaries, compared to UEBMI beneficiaries, raised concerns regarding quality of EOL care and financial burdens of NRCMS and URBMI beneficiaries. Purposive hospice care intervention might be warranted to address EOL care for these beneficiaries in China.

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