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1.
Mol Neurobiol ; 2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-38190023

RESUMEN

Alzheimer's disease (AD) is a neurodegenerative disease with a long incubation period. While extensive research has led to the construction of long non-coding RNA (lncRNA)-associated competing endogenous RNA (ceRNA) regulatory networks, which primarily derived from differential analyses between clinical AD patients and control individuals or mice, there remains a critical knowledge gap pertaining to the dynamic alterations in transcript expression profiles that occur with age, spanning from the pre-symptomatic stage to the onset of AD. In the present study, we examined the transcriptomic changes in AD model mice at three distinct stages: the unaffected (un-) stage, the pre-onset stage, and the late-onset stage, and identified 14, 57, and 99 differentially expressed mRNAs (DEmRs) in AD model mice at 3, 6, and 12 months, respectively. Among these, we pinpointed 16 mRNAs closely associated with inflammation and immunity and excavated their lncRNA-mRNA regulatory network based on a comprehensive analysis. Notably, our preliminary analysis suggested that four lncRNAs (NONMMUT102943, ENSMUST00000160309, NONMMUT083044, and NONMMUT126468), eight miRNAs (miR-34a-5p, miR-22-5p, miR-302a/b-3p, miR-340-5p, miR-376a/b-5p, and miR-487b-5p), and four mRNAs (C1qa, Cd68, Ctss, and Slc11a1) may play pivotal roles in orchestrating immune and inflammatory responses during the early stages of AD. Our study has unveiled age-related AD risk genes, and provided an analytical framework for constructing lncRNA-mRNA networks using time series data and correlation analysis. Most notably, we have successfully constructed a comprehensive regulatory ceRNA network comprising genes intricately linked to inflammatory and immune functions in AD.

4.
Ying Yong Sheng Tai Xue Bao ; 33(10): 2743-2752, 2022 Oct.
Artículo en Chino | MEDLINE | ID: mdl-36384610

RESUMEN

In this study, we examined plant C:N:P stoichiometry of herbaceous plants in different sections (stable area, unstable area and deposition area) of the unstable slope on both shade and sunny aspects of dry-hot valley with different soil properties. The results showed that C concentration (320.59 g·kg-1), N concentration (12.15 g·kg-1), and N:P ratio (25.37) of shoot on the unstable slope were significantly higher than those of root, with 254.01 g·kg-1, 6.12 g·kg-1 and 13.43, respectively. The average value of the C:N ratio was significantly higher in root (43.09) than shoot (31.90). The C content and N:P ratio of shoot and root in stable and unstable areas were significantly higher than in deposition area, whereas the N content in unstable area was significantly higher than that in deposition area on the sunny slope. In addition, the N and P contents of shoot and the root P content in deposition area were significantly higher than in stable and unstable areas, whereas the C content of root in stable and unstable areas were significantly higher than in deposition area on the shade slope. Moreover, the shoot growth of plants was mainly limited by P, whereas root growth was mainly limited by N and the limitation gradually increased as the section goes down. Soil water content (SWC) was an important factor controlling the C, N, and P contents change of shoot with the relative influence ratios of 28.8%, 20.8%, and 19.9%, respectively. Soil organic carbon (SOC) had a significant impact on the C and P contents of root with the relative influence ratios of 49.5% and 22.1%. The change of root N content was mainly affected by soil pH (24.3%). Our results revealed that nutrient allocation of plant was significantly affected by slope aspects, sections and soil factors, which were mainly constituted by SWC, SOC, and soil pH.


Asunto(s)
Carbono , Suelo , Suelo/química , Plantas , Agua , Nutrientes
5.
Nano Lett ; 21(18): 7761-7768, 2021 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-34460270

RESUMEN

Hot carrier harvest could save 30% energy loss in solar cells. So far, however, it is still unreachable as the photoexcited hot carriers are short-lived, ∼1 ps, determined by a rapid relaxation process, thus invalidating any reprocessing efforts. Here, we propose and demonstrate a feasible route to reserve hot electrons for efficient collection. It is accomplished by an intentional mix of cubic zinc-blend and hexagonal wurtzite phases in III-V semiconductor nanowires. Additional energy levels are then generated above the conduction band minimum, capturing and storing hot electrons before they cool down to the band edges. We also show the superiority of core/shell nanowire (radial heterostructure) in extracting hot electrons. The strategy disclosed here may offer a unique opportunity to modulate hot carriers for efficient solar energy harvest.

6.
Anal Methods ; 12(41): 4996-5003, 2020 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-33021259

RESUMEN

Different valence states of chromium ions possess huge differences in toxicity. Hence, it is an innovative idea to design a reasonable probe to detect Cr according to the toxicity characteristics of different valence states. We report a novel, rapid, simple and accurate probe for the detection of Cr3+ and Cr6+ ions. As a probe, gold nanoparticles (Au NPs) are successfully modified using tartaric acid (TA) and 2-[4-(2-hydroxyethyl)-1-piperazinyl] ethanesulfonic acid (HEPES) via a two-step modification; the probe shows an increase in the sensitivity towards Cr6+ and decreases towards Cr3+, which is consistent with their toxicity characteristics, benefiting the assessment of total Cr toxicity. The proposed probe achieves considerable two-channel (ultraviolet absorption spectrum and naked eye vision) detection of Cr3+ and Cr6+ providing wide linearity regions and low detection limits. Meanwhile, the results of the interference experiments and analysis of the real samples showed high selectivity and accuracy of the proposed method. With popularization, this method possesses great potential in environmental monitoring and control.


Asunto(s)
Colorimetría , Nanopartículas del Metal , Cromo/toxicidad , Oro , Iones , Límite de Detección , Nanopartículas del Metal/toxicidad
7.
Opt Express ; 28(22): 33556-33563, 2020 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-33115015

RESUMEN

The performance of high-operating-temperature (HOT) longwavelength infrared (LWIR) HgCdTe avalanche photodiodes (APDs) is significantly limited by the increasing dark current related to temperature. In this paper, a novel barrier-blocking LWIR pBp-APD structure is proposed and studied, and the results show that the dark current of pBp-APD is significantly restricted compared with conventional APD without sacrificing the gain at high temperature. Furthermore, the reduction of avalanche dark current is found to be the key points of the significant suppression of dark current. The physical essence of this reduction is revealed to be the depletion of carriers in the absorption region, and the feasibility of the improved structure is further confirmed by the analysis of its energy band and electric field distribution. In addition, the reduction of gain-normalized dark current (GNDC) does not need to sacrifice the gain. The proposed LWIR pBp-APD paves the way for development of high operation temperature infrared APDs.

8.
Adv Mater ; 32(45): e2005037, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32985021

RESUMEN

Low-symmetry 2D materials with unique anisotropic optical and optoelectronic characteristics have attracted a lot of interest in fundamental research and manufacturing of novel optoelectronic devices. Exploring new and low-symmetry narrow-bandgap 2D materials will be rewarding for the development of nanoelectronics and nano-optoelectronics. Herein, sulfide niobium (NbS3 ), a novel transition metal trichalcogenide semiconductor with low-symmetry structure, is introduced into a narrowband 2D material with strong anisotropic physical properties both experimentally and theoretically. The indirect bandgap of NbS3 with highly anisotropic band structures slowly decreases from 0.42 eV (monolayer) to 0.26 eV (bulk). Moreover, NbS3 Schottky photodetectors have excellent photoelectric performance, which enables fast photoresponse (11.6 µs), low specific noise current (4.6 × 10-25 A2 Hz-1 ), photoelectrical dichroic ratio (1.84) and high-quality reflective polarization imaging (637 nm and 830 nm). A room-temperature specific detectivity exceeding 107 Jones can be obtained at the wavelength of 3 µm. These excellent unique characteristics will make low-symmetry narrow-bandgap 2D materials become highly competitive candidates for future anisotropic optical investigations and mid-infrared optoelectronic applications.

9.
Access Microbiol ; 2(7): acmi000133, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32974596

RESUMEN

The studies of coronavirus disease 2019 (COVID-19) have mainly focused on epidemiological and clinical features of patients, but transmission dynamics of SARS-CoV-2 virus after patients have recovered is still poorly understood. Here we report a case with prolonged viral shedding of COVID-19 in Kaohsiung, Taiwan. This patient started to show myalgia and malaise in Wuhan, and the onset of the fever was on days 7-14 of the illness. All clinical and radiological results returned to normal after day 26, however, viral shedding was still evident 14 days later. Sequence analysis of the genome of the Taiwanese SARS-CoV-2 isolate from this patient reveals new mutations in viral replicase and ORF3a, indicating that COVID-19 evolves very quickly. Prolonged viral shedding and new mutations in the viral genome could potentially complicate the control of the COVID-19 pandemic.

10.
Nanotechnology ; 31(29): 294004, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32235081

RESUMEN

In recent years, quasi-1D semiconductor nanowires have attracted significant research interest in the field of optoelectronic devices. Indium arsenide (InAs) nanowire, a III-V compound semiconductor structure with a narrow band gap, shows high electron mobility and high absorption from the visible to the mid-wave infrared (MWIR), holding promise for room-temperature high-performance infrared photodetectors. Therefore, the material growth, device preparation and performance characteristics have attracted increasing attention, enabling high-sensitivity InAs nanowire photodetector from the visible to the MWIR at room temperature. This review starts by discussing the growth process of the low-dimensional structure and elementary properties of the material, such as the crystalline phase, mobility, morphology, surface states and metal contacts. Then, three solutions, including the visible-light-assisted infrared photodetection technology, vertical nanowire-array technology and band engineering by the growth of InAsSb nanowires with increasing Sb components, are elaborated to obtain longer cut-off wavelength MWIR photodetectors based on single InAs nanowire and its heterojunction structure. Finally, the potential and challenges of the state-of-the-art optoelectronic technologies for InAs nanowire MWIR photodetectors are summarized and compared, and preliminary suggestions for the technical development route and prospects are presented. This review mainly delineates the research progress of material growth, device fabrication and performance characterization of InAs nanowire MWIR photodetectors, providing a reference for the development of the next-generation high-performance photodetectors over a wide spectrum range.

11.
ScientificWorldJournal ; 2013: 931980, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24348195

RESUMEN

The effect of donor-like surface traps on two-dimensional electron gas (2DEG) and drain current collapse of AlGaN/GaN high electron mobility transistors (HEMTs) has been investigated in detail. The depletion of 2DEG by the donor-like surface states is shown. The drain current collapse is found to be more sensitive to the addition of positive surface charges. Surface trap states with higher energy levels result in weaker current collapse and faster collapse process. By adopting an optimized backside doping scheme, the electron density of 2DEG has been improved greatly and the current collapse has been greatly eliminated. These results give reference to the improvement in device performance of AlGaN/GaN HEMTs.


Asunto(s)
Compuestos de Aluminio , Electrones , Galio , Transistores Electrónicos
12.
Zhonghua Gan Zang Bing Za Zhi ; 21(10): 747-52, 2013 Oct.
Artículo en Chino | MEDLINE | ID: mdl-24331632

RESUMEN

OBJECTIVE: To investigate the effects and mechanism of intracellular 4-hydroxynonenal (4-HNE) accumulation on tumor necrosis factor (TNF)-induced hepatotoxicity in alcoholic liver disease (ALD). METHODS: An ALD model was established in male C57BL/6 mice (6-8 weeks old) by feeding an ethanol-containing diet for 5 weeks; mice given regular (non-ethanol) diet served as controls. ALD-related changes in 4-HNE and TNF levels were detected by western blotting. The underlying mechanisms of this molecular effect were examined by pre-treating HepG2 cells with 4-HNE followed by exposure to various concentrations of TNF. Effects on cell death were evaluated by MTT assay. Effects on TNF-mediated upstream factors' expression were detected by ELISA, western blotting, and real-time PCR. Effects on the TNF-induced inhibitor of NF-kB (IkBa) activity (phosphorylation status) and its formation of adducts were detected by western blotting and immunoprecipitation. RESULTS: ALD mice showed increased hepatic 4-HNE and TNF levels, and the increases were associated with extent of liver injury. Cell culture studies revealed that 4-HNE, at non-toxic concentrations, sensitized hepatocytes to TNF killing, which was associated with suppressed NF-kB trans activity. Furthermore, 4-HNE prevented phosphorylation of IkBa without affecting upstream IkB kinase activity. The ALD-enhanced 4-HNE content was found to associated with increased formation of 4-HNE-IkBa adduction for both the 4-HNE - treated hepatocytes in culture and in the livers of ALD mice. CONCLUSION: Alcohol-induced increase in 4-HNE accumulation represents a potent and clinically relevant mechanism of sensitizing hepatocytes to TNF-induced toxicity. These data support the notion that decreasing or eliminating accumulated intracellular 4-HNE can serve as a potential therapeutic option for ALD.


Asunto(s)
Aldehídos/metabolismo , Hepatopatías Alcohólicas/metabolismo , Transducción de Señal , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Etanol/toxicidad , Células Hep G2 , Humanos , Proteínas I-kappa B/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , FN-kappa B/metabolismo
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