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1.
Dis Markers ; 2019: 6514608, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31583029

RESUMO

Neuroblastoma is the most common seen solid neural tumor in children less than age one. As mutation in the miR-34b/c gene is observed in several types of human malignancies, there likely to be similar events that contribute to the pathogenesis of neuroblastoma. We hypothesize that polymorphism in the miR-34b/c gene might predispose to neuroblastoma. Here, we conducted this replication study by genotyping rs4938723 T>C from miR-34b/c in Hunan children (162 subjects with neuroblastoma and 270 control subjects) and examined its effect on the risk of neuroblastoma. We determined such association using logistic regression, adjusted for age and gender. Relative to those with TT genotype, subjects with C allele had reduced neuroblastoma risk (TC vs. TT: adjusted OR = 0.46, 95%CI = 0.30-0.71; additive model: adjusted OR = 0.64, 95%CI = 0.47-0.88; TC/CC vs. TT: adjusted OR = 0.49, 95%CI = 0.33-0.73). Stratified analysis revealed that rs4938723 TC/CC carriers were less likely to develop neuroblastoma for patients in the subgroups of age ≤ 18 months, age > 18 months, females, males, tumors in retroperitoneal, tumors in other sites, and clinical stages II, III, IV, and III+IV. Our findings verified miR-34b/c rs4938723 C variant allele as a protective factor for the risk of neuroblastoma. Further investigation of how miR-34b/c rs4938723 T>C might modify neuroblastoma risk is warranted.

2.
Ann Rheum Dis ; 2019 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-31537547

RESUMO

OBJECTIVES: Open-labelled clinical trials suggested that low-dose IL-2 might be effective in treatment of systemic lupus erythematosus (SLE). A double-blind and placebo-controlled trial is required to formally evaluate the safety and efficacy of low-dose IL-2 therapy. METHODS: A randomised, double-blind and placebo-controlled clinical trial was designed to treat 60 patients with active SLE. These patients received either IL-2 (n=30) or placebo (n=30) with standard treatment for 12 weeks, and were followed up for additional 12 weeks. IL-2 at a dose of 1 million IU or placebo was administered subcutaneously every other day for 2 weeks and followed by a 2-week break as one treatment cycle. The primary endpoint was the SLE Responder Index-4 (SRI-4) at week 12. The secondary endpoints were other clinical responses, safety and dynamics of immune cell subsets. RESULTS: At week 12, the SRI-4 response rates were 55.17% and 30.00% for IL-2 and placebo, respectively (p=0.052). At week 24, the SRI-4 response rate of IL-2 group was 65.52%, compared with 36.67% of the placebo group (p=0.027). The primary endpoint was not met at week 12. Low-dose IL-2 treatment resulted in 53.85% (7/13) complete remission in patients with lupus nephritis, compared with 16.67% (2/12) in the placebo group (p=0.036). No serious infection was observed in the IL-2 group, but two in placebo group. Besides expansion of regulatory T cells, low-dose IL-2 may also sustain cellular immunity with enhanced natural killer cells. CONCLUSIONS: Low-dose IL-2 might be effective and tolerated in treatment of SLE. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registries (NCT02465580 and NCT02932137).

3.
Artigo em Inglês | MEDLINE | ID: mdl-31488722

RESUMO

Different memory components are forgotten through distinct molecular mechanisms. In Drosophila, the activation of 2 Rho GTPases (Rac1 and Cdc42), respectively, underlies the forgetting of an early labile memory (anesthesia-sensitive memory, ASM) and a form of consolidated memory (anesthesia-resistant memory, ARM). Here, we dissected the molecular mechanisms that tie Rac1 and Cdc42 to the different types of memory forgetting. We found that 2 WASP family proteins, SCAR/WAVE and WASp, act downstream of Rac1 and Cdc42 separately to regulate ASM and ARM forgetting in mushroom body neurons. Arp2/3 complex, which organizes branched actin polymerization, is a canonical downstream effector of WASP family proteins. However, we found that Arp2/3 complex is required in Cdc42/WASp-mediated ARM forgetting but not in Rac1/SCAR-mediated ASM forgetting. Instead, we identified that Rac1/SCAR may function with formin Diaphanous (Dia), a nucleator that facilitates linear actin polymerization, in ASM forgetting. The present study, complementing the previously identified Rac1/cofilin pathway that regulates actin depolymerization, suggests that Rho GTPases regulate forgetting by recruiting both actin polymerization and depolymerization pathways. Moreover, Rac1 and Cdc42 may regulate different types of memory forgetting by tapping into different actin polymerization mechanisms.

4.
Zhen Ci Yan Jiu ; 44(9): 625-31, 2019.
Artigo em Chinês | MEDLINE | ID: mdl-31532129

RESUMO

OBJECTIVE: To investigate the effect of different frequencies of electroacupuncture (EA) on motor function and expression of autophagy-related proteins microtubule-associated protein light chain 3 (LC3), etc. in spinal cord injury (SCI) rats, so as to reveal its underlying mechanisms and provide a reference for clinical application. METHODS: A total of 100 male SD rats were randomly divided into sham control, model, 2 Hz-EA, 100 Hz-EA and 2 Hz/100 Hz-EA groups(n=20 in each group). EA (2 Hz, 100 Hz or 2 Hz/100 Hz, 0.4-0.5-0.6 mA increased by 0.1 mA every10 min) was applied to "HuatuoJiaji" (EX-HN1, T9 and T11) for 30 min, once a day for 7 days. The rat's hindlimb motor function was assessed by using Basso, Beattie and Bresnahan(BBB) locomotor rating scale, inclined plane test and plantar imprinting test, separately. The histological changes and neuronal apoptosis of the spinal cord tissue were observed by Fluoro-Jade B (FJB) and Nissl staining, respectively. The expression of LC3, Beclin 1 and cleaved Caspase-3 proteins in the spinal cord was detected by Western blot. RESULTS: After modeling, the BBB scores and the angles of inclined plane on day 1, 3 and 7 were significantly decreased (P<0.001), and the number of FJB positive cells, and the expression levels of Beclin 1 and cleaved Caspase-3 proteins were considerably increased in the model group compared with the sham control group (P<0.001, P<0.05). After EA intervention, the BBB score and the angles of inclined plate on day 3 in the 2 Hz/100 Hz-EA group (rather than in the 2 Hz- and 100 Hz-EA groups), the BBB score and the angles of inclined plate on day 7 in both 2 Hz/100 Hz and 100 Hz-EA groups(rather than in the 2 Hz-EA group), and the expression levels of Beclin 1 and LC3-Ⅱ/Ⅰ in both 2 Hz/100 Hz and 100 Hz-EA groups (rather than in the 2 Hz-EA group) on day 7 were obviously increased (P<0.001, P<0.01, P<0.05), while the number of FJB-positive neurons in the 3 EA groups, and the expression of cleaved Caspase-3 protein in both 2 Hz/100 Hz and 100 Hz-EA groups and the LC3-Ⅱ/Ⅰ in the 2 Hz-EA group were obviously decreased relevant to the model group (P<0.001, P<0.05). The expression of Beclin 1 in the 100 Hz-EA group was obviously decreased relevant to the 2 Hz/100 Hz-EA group (P<0.05) .Nissl staining displayed appearance of cavities and fuzzy shape of Nissl bodies with light coloration in the injured spinal cord of model group, which was milder in both 2 Hz/100 Hz-EA and 100 Hz-EA groups. Plantar imprinting tests showed dragging gait prints in the model group due to disability in movement, and relatively distinct foot imprints in both 2 Hz/100 Hz and 100 Hz-EA groups. CONCLUSION: Both 100 Hz and 2 Hz/100 Hz-EA can effectively promote the recovery of hindlimb locomotor function of SCI rats, which may be related to its function in promoting autophagy of damaged nerve cells and in reducing neuronal apoptosis.


Assuntos
Eletroacupuntura , Traumatismos da Medula Espinal , Animais , Proteína Beclina-1 , Membro Posterior , Masculino , Proteínas Associadas aos Microtúbulos , Ratos , Ratos Sprague-Dawley , Medula Espinal
5.
Sci Rep ; 9(1): 12907, 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31501472

RESUMO

The necrobiome is the postmortem community that includes bacteria, fungi, arthropods, and other cadaver-associated organisms. It has been suggested as biological evidence for forensic investigation. Fungi form distinctive mildew spots in colonizing decomposing bodies, converting them into moldy cadavers. However, the postmortem fungal community consists of more than these visible species. Characterizing the succession pattern of the fungal community during decomposition is valuable not only for understanding the ecosystem composition of the cadaver decomposition islands but also for contributing to forensic investigations. In the present study, the fungal composition of pig cadavers and succession patterns during decomposition were investigated with high-throughput sequencing. The succession patterns were easier to discern in outdoor cadavers, compared with those that were placed indoors. The metabarcoding approach revealed trends linking particular fungal taxa with specific postmortem intervals (PMIs). Dominant species increased notably in cadavers and soil. Furthermore, the succession of the soil community was driven by the cadaver decomposition. Significant mycoflora differences were observed between environmental and cadaveric soil. The results obtained suggested that postputrefaction mycoflora have considerable potential for PMI estimation, particularly in cases that involve heavily decomposed bodies. In addition, the diversity of fungal communities revealed by the metabarcoding approach allowed us to discriminate the sites of cadaver decomposition, implying that postputrefaction mycoflora may be helpful in identifying the environment in which a cadaver has been placed, or the original location from which a cadaver has been moved. Our results provide an important step towards developing fungal evidence for use in forensic science and add to the growing body of work on postmortem microbial communities.

6.
Nanoscale ; 11(37): 17444-17459, 2019 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-31531431

RESUMO

Collective oscillation of quasi-free electrons on the surface of metallic plasmonic nanoparticles (NPs) in the ultraviolet to near-infrared (NIR) region induces a strong electromagnetic enhancement around the NPs, which leads to numerous important applications. These interesting far- and near-field optical characteristics of the plasmonic NPs can be typically obtained from numerical simulations for theoretical guidance of NP design. However, traditional numerical simulations encounter irreconcilable conflicts between the accuracy and speed due to the high demand of computing power. In this work, we utilized the machine learning method, specifically the deep neural network (DNN), to establish mapping between the far-field spectra/near-field distribution and dimensional parameters of three types of plasmonic NPs including nanospheres, nanorods, and dimers. After the training process, both the forward prediction of far-field optical properties and the inverse prediction of on-demand dimensional parameters of NPs can be accomplished accurately and efficiently with the DNN. More importantly, we have achieved for the first time ultrafast and accurate prediction of two-dimensional on-resonance electromagnetic enhancement distributions around NPs by greatly reducing the amount of electromagnetic data via screening and resampling methods. These near-field predictions can be realized typically in less than 10-2 seconds on a laptop, which is 6 orders faster than typical numerical simulations implemented on a server. Therefore, we demonstrate that the DNN is an ultrafast, highly efficient, and computing resource-saving tool to investigate the far- and near-field optical properties of plasmonic NPs, especially for a number of important nano-optical applications such as surface-enhanced Raman spectroscopy, photocatalysis, solar cells, and metamaterials.

7.
Food Res Int ; 125: 108624, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31554059

RESUMO

The dried and aged pericarps of Citri Reticulatae are condiments and medicinal products in southeast and eastern Asia for hundreds of years, among which Pericarpium Citri Reticulatae 'Chachiensis' (PCR-C) is the premium one with obvious health benefits. In order to explore the microbiota in PCR-C and their relationship with the chemical components during aging, culture-independent methods were applied to investigate PCR-C microbiota for the first time. Here in different PCR-C samples, 16S rRNA gene amplicon sequencing revealed common central bacterial community, which were absent or only accounted for small proportion in fresh pericarps or jute bag controls. Bacillus and Lactococcus were the top two dominant genera in PCR-C with acidic pH (4.06-4.51) and low moisture (11.48%-19.13%). Several OTUs were found to closely relate with specific compositions in essential oils and phenolics, such as d-limonene and nobiletin, which contributed to PCR-C flavor and quality. As the first study to reveal the central bacterial communities in PCR-C, it provides new insights to improve the quality and aging process of traditional Pericarpium Citri Reticulatae, and lays foundation for functional characterization of the microbes within.

8.
Artif Cells Nanomed Biotechnol ; 47(1): 3758-3764, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31556307

RESUMO

Diabetic retinopathy (DR) is one of the most common diabetic complications and remains the leading cause of vision loss among adults. C1q/TNF-related protein 3 (CTRP3) is a member of CTRP family that has been found to be involved in the progression of diabetes mellitus and diabetic complications. However, the role of CTRP3 in DR has not been fully understood. In the present study, the results showed that CTRP3 expression was significantly decreased in DR patients compared with controls. In vitro investigations proved that overexpression of CTRP3 improved cell viability of ARPE-19 cells in response to high glucose (HG) stimulation. CTRP3 also attenuated HG-induced oxidative stress in ARPE-19 cells with decreased levels of reactive oxygen species (ROS) and malondialdehyde (MDA), and increased superoxide dismutase (SOD) activity. Apoptotic rate was significantly decreased in CTRP3 overexpressing ARPE-19 cells. Besides, bcl-2 expression was increased, while bax expression was decreased by CTRP3 overexpression. Moreover, overexpression of CTRP3 enhanced the activation of nuclear factor erythroid 2-related factor 2 (Nrf2)/hemeoxygenase-1 (HO-1) pathway in HG-stimulated ARPE-19 cells, and Nrf2 knockdown reversed CTRP3-mediated oxidative stress and apoptosis. These findings suggested that CTRP3 attenuated HG-stimulated oxidative stress and apoptosis in ARPE-19 cells, which were mediated by activation of Nrf2/HO-1 pathway.

9.
Biosens Bioelectron ; 144: 111692, 2019 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-31522099

RESUMO

A highly flexible electrochemical assay based on target-triggered DNAzyme spiders was proposed for the detection of telomerase. The DNAzyme-telomerase substrate primers (D-TSP) containing Cu2+-dependent DNAzymes serve as recognition elements, and primers of telomerase. Telomerase extracted from Hela cells recognize the D-TSP and elongated with DNA sequence repeats. A synthetic telomerase product hybridized with scaffold sequences of two DNAzyme-tethered probes on the basis of the mechanism of the proximity-ligation assay. The three-leg DNAzyme spiders has been assembled and initiated the autonomous hybridization/nicking/displacement cycles on substrate modified surface. The cleaved ferrocene-labeled fragements are adsorbed on gold surface leading to an increase in the electrochemical signal. As a result, the one input target, telomerase, release large amount of ferrocene-labeled DNA strands, achieving an exponential signal amplification and an excellent improvement in sensitivity over single molecule or two-component 'sandwich' binding complexes. Our proposed biosensor showed a nonlinear dependence with Hela cell numbers, ranging from 25 to 2000 with a detection limit of 10 cells. Telomerase activities from different cell lines were also successfully evaluated. Our electrochemical strategy based on target-triggered DNAzyme spiders was enzyme-free, PCR-free, simple in operation which indicated that it expected to expand the scope of DNA nanotechnology in the areas of clinical diagnosis.

10.
Indian J Ophthalmol ; 67(10): 1629-1633, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31546497

RESUMO

Purpose: This study evaluated bimanual intracapsular irrigation-aspiration for ectopia lentis with use of a small incision for 4-point scleral fixation of a foldable posterior-chamber intraocular lens (IOL) and anterior vitrectomy in patients with Marfan syndrome. Methods: We performed a retrospective study of 18 eyes from 10 patients with Marfan syndrome who underwent surgical intervention for ectopia lentis at our clinic between July 2012 and September 2018. In this study, intraoperative and postoperative complications, uncorrected visual acuity, best-corrected visual acuity, spherical equivalent, intraocular pressure, and endothelial cell density were evaluated. Results: No intraoperative complications were reported. In all cases, early postoperative evaluation revealed a clear cornea, round pupil, and well-centered IOL. Mean logMAR uncorrected visual acuity improved from 1.09 preoperatively to 0.56 postoperatively (P < 0.05). Mean logMAR best-corrected visual acuity improved from 0.45 preoperatively to 0.17 postoperatively (P < 0.05). Aside from transient ocular hypertension, no postoperative complications were reported. Conclusion: The combined surgical technique presented above yields excellent visual outcomes with an extremely low incidence of complications. This approach is simple, safe, and effective in the treatment of ectopia lentis in patients with Marfan syndrome.

11.
Artigo em Inglês | MEDLINE | ID: mdl-31525889

RESUMO

Surface oxygen vacancy can greatly affect the properties of transition-metal oxides. However, engineering oxygen vacancy-abundant transition-metal oxides with high specific surface area (SSA) remains challenging. At present, the generation of oxygen vacancies in metal oxides is time-consuming and less environmentally friendly by chemical leaching methods that usually require additional waste treatment. Herein, a series of oxygen vacancy-abundant transition-metal oxides with high SSA are constructed via a lattice refining strategy. This strategy is realized by urea-assisted ball milling pyrolysis and is green, efficient, and universal. The oxygen vacancies promote the mobility of oxygen, leading to a boosted catalytic oxidation performance of aromatic sulfides. Such a strategy provides an efficient approach to manufacturing oxygen vacancies on transition-metal oxides, which may be beneficial for various related applications as an effective catalytic material.

12.
Artigo em Inglês | MEDLINE | ID: mdl-31552730

RESUMO

The discharge of large amounts of sewage has caused enormous damage to the environment and human health. There is an urgent need for efficient and environmentally friendly materials to deal with such troubles. Materials with emulsion separation have attracted everyone's attention. In this study, ZIF-8 and Co-PDMS modified multi-walled carbon nanotubes films were fabricated. First, the surface of the nanotubes films was modified with ZIF-8 by in-situ growth, and then a Co-PDMS layer was added by dip coating. The membrane has excellent wettability, and it is superhydrophobic and superoleophilic in air. The separation efficiency of water-in-oil emulsions reaches more than 99.9%, and it has outstanding separation ability for corrosive emulsions. Moreover, the membrane has excellent self-healing ability, and it can rapidly heal at normal temperature after being damaged. This makes the film more suitable for practical oily wastewater treatment. We performed related research and propose the possible self-healing mechanism.

14.
Oncogene ; 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31444414

RESUMO

Drug resistance, including epirubicin-based therapeutic resistance, is one of the major reasons responsible for the unfavorable prognosis of patients diagnosed with breast cancer (BC). Acquired chemoresistance and metastatic properties have been identified to be closely associated with the process of epithelial-mesenchymal transition (EMT). Recently, dysregulation of long non-coding RNAs (lncRNAs) have been increasingly reported to perform promotive or suppressive functions in chemoresistance and EMT process in multiple cancers. However, relevant novel lncRNA participating in epirubicin resistance and EMT and its underlying molecular mechanisms remain unknown in BC. Herein, we established the epirubicin-resistant breast cancer cell subline (MCF-7/ADR), which presented mesenchymal phenotype and increased metastatic potential. A panel of differentially expressed lncRNAs, including 268 upregulated and 49 downregulated lncRNAs, were identified by high-flux microarray investigation in MCF-7 and MCF-7/ADR cells. The novel lncRNA NONHSAT101069 was significantly overexpressed in BC specimens, BC cell lines, and epirubicin-resistant cell sublines. The knockdown of NONHSAT101069 significantly repressed, whereas overexpression of NONHSAT101069 promoted the epirubicin resistance, migration, invasion and EMT process of BC cells both in vitro and in vivo. Further mechanism-related researches uncovered that NONHSAT101069 functioned as a ceRNA (competing endogenous RNA) via sponging miR-129-5p. Twist1 was a direct downstream protein of NONHSAT101069/miR-129-5p axis in BC cells. To conclude, NONHSAT101069 was upregulated in BC tissues and promoted epirubicin resistance, migration and invasion of BC cells via regulation of NONHSAT101069/miR-129-5p/Twist1 axis, highlighting its potential as an oncogene and a therapeutic biomarker for BC.

15.
Nurse Educ Today ; 82: 51-57, 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31437783

RESUMO

OBJECTIVE: The aim of this meta-analysis is to investigate the effects of blended learning on nursing students' knowledge, skills and satisfaction. METHODS: We searched EMBASE, PubMed, CINAHL, Cochrane Library for publications in English up to December 2018. Two researchers independently screened the literature and extracted the data. Meta-analysis was performed with Revman5.0 for the eligible studies. RESULTS: A total of 8 studies met the inclusion criteria of meta-analysis, including 574 nursing students. Compared with traditional teaching, blended learning could effectively improve nursing students' knowledge (SMD = 0.70, 95% CI [0.52, 0.87], P < 0.00001) and satisfaction (SMD = 0.72, 95% CI [0.08, 0.59], P = 0.01), and tended to improve the skills although without significant difference (SMD = 0.58, 95% CI [-0.17, 1.32], P = 0.13). CONCLUSIONS: Blended learning can effectively improve the knowledge and satisfaction of nursing students. Therefore, blended learning can be used as a teaching method in nursing education.

16.
Nat Commun ; 10(1): 3905, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31467266

RESUMO

Surface-enhanced Raman spectroscopy (SERS) is advantageous over fluorescence for bioimaging due to ultra-narrow linewidth of the fingerprint spectrum and weak photo-bleaching effect. However, the existing SERS imaging speed lags far behind practical needs, mainly limited by Raman signals of SERS nanoprobes. In this work, we report ultrabright gap-enhanced Raman tags (GERTs) with strong electromagnetic hot spots from interior sub-nanometer gaps and external petal-like shell structures, larger immobilization surface area, and Raman cross section of reporter molecules. These GERTs reach a Raman enhancement factor beyond 5 × 109 and a detection sensitivity down to a single-nanoparticle level. We use a 370 µW laser to realize high-resolution cell imaging within 6 s and high-contrast (a signal-to-background ratio of 80) wide-area (3.2 × 2.8 cm2) sentinel lymph node imaging within 52 s. These nanoprobes offer a potential solution to overcome the current bottleneck in the field of SERS-based bioimaging.

17.
Opt Lett ; 44(17): 4191-4194, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31465360

RESUMO

The influence of nonlinear phase modulations on third-harmonic (TH) conversion in silica microfibers is experimentally demonstrated. By utilizing such influence, enhanced narrow-bandwidth ultraviolet TH is generated at a high signal-to-noise ratio (33 dB) and an average power of several hundred nanowatts. Detailed trends of TH power against input pump power were characterized with peak pump power up to 2.5 kW, and the results agree with predicted features, confirming that harmonic output could be optimized with adaptive control of the phase mismatch.

18.
Molecules ; 24(16)2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31430852

RESUMO

Anatase/rutile mixed-phase TiO2 nanoparticles were synthesized through a simple sol-gel route with further calcination using inexpensive titanium tetrachloride as a titanium source, which effectively reduces the production cost. The structural and optical properties of the prepared materials were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and UV-vis adsorption. The specific surface area was also analyzed by Brunauer-Emmett-Teller (BET) method. The anatase/rutile mixed-phase TiO2 nanocomposites containing of rod-like, cuboid, and some irregularly shaped anatase nanoparticles (exposed {101} facets) with sizes ranging from tens to more than 100 nanometers, and rod-like rutile nanoparticles (exposed {110} facets) with sizes ranging from tens to more than 100 nanometers. The photocatalytic activities of the obtained anatase/rutile mixed-phase TiO2 nanoparticles were investigated and compared by evaluating the degradation of hazardous dye methylene blue (MB) under ultraviolet light illumination. Compared to the commercial Degussa P25-TiO2, the mixed-phase TiO2 nanocomposites show better photocatalytic activity, which can be attributed to the optimal anatase to rutile ratio and the specific exposed crystal surface on the surface. The anatase/rutile TiO2 nanocomposites obtained at pH 1.0 (pH1.0-TiO2) show the best photocatalytic activity, which can be attributed to the optimal heterojunction structure, the smaller average particle size, and the presence of a specific exposed crystal surface. The enhanced photocatalytic activity makes the prepared anatase/rutile TiO2 photocatalysts a potential candidate in the removal of the organic dyes from colored wastewater.

19.
Adv Mater ; 31(37): e1806424, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31379043

RESUMO

Memcapacitors are emerging as an attractive candidate for high-density information storage due to their multilevel and adjustable capacitances and long-term retention without a power supply. However, knowledge of their memcapacitive mechanism remains unclear and accounts for the limited implementation of memcapacitors for multilevel memory technologies. Here, repeatable and reproducible quaternary memories fabricated from hybrid perovskite (CH3 NH3 SnBr3 ) memcapacitors are reported. The device can be modulated to at least four capacitive states ranging from 0 to 169 pF with retention for 104 s. Impressively, an effective device yield approaching 100% for quaternary memory switching is achieved by a batch of devices; each state has a sufficiently narrow distribution that can be distinguished from the others and is superior to most multilevel memories that have a low device yield as well as an overlapping distribution of states. The memcapacitive switching stems from the modulated p-i-n junction capacitance triggered by Br- migration, as demonstrated by in situ element mapping, X-ray photoelectron spectra, and frequency-dependent capacitance measurements; this mechanism is different from the widely reported memristive switching involving filamentary conduction. The results provide a new way to produce high-density information storage through memcapacitors.

20.
Insect Biochem Mol Biol ; 113: 103207, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31421206

RESUMO

The fat body is distributed throughout the body of insects, playing the essential role in intermediary metabolism and nutrient storage. However, the function of differentiation of fat bodies adhering to different tissues remains largely unknown. Here, we identified a fat body-like tissue (FLT) surrounding testis follicles and described its features at morphological, cellular and molecular levels. The FLT is morphologically distinguished with the abdominal fat body (FB) and dominated by diploid cells instead of polyploid cells. The transcriptomic analysis demonstrated that the FLT and FB have dramatically different gene expression profiles. Moreover, genes in the cell cycle pathway, which include both DNA replication- and cell division-related genes, were successively active during development of the FLT, suggesting that FLT cells possibly undergo a mitotic cycle rather than an endocycle. Deprivation of the FLT resulted in distortion of the testis follicles, disappearance of sperm bundles, reduction of total sperm number and increase of dead sperm, indicating a critical role of the FLT in the spermatogenesis in testis follicles. The special functional differentiation of the two similar tissues suggested that FLT-FB cells are able to establish a promising system to study mitotic-to-endocycle transition.

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