685 research outputs found

    Sustained Robust Exciton Emission in Suspended Monolayer WSe_2 within the Low Carrier Density Regime for Quantum Emitter Applications

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    The development of semiconductor optoelectronic devices is moving toward low power consumption and miniaturization, especially for high-efficiency quantum emitters. However, most of these quantum sources work at low carrier density region, where the Shockley-Read-Hall recombination may dominant and seriously reduce the emission efficiency. In order to diminish the affection of carrier trapping and sustain a strong photoluminescence emission under low power pumping condition, we investigated on the influence of Suspending to monolayered tungsten diselenide, novel two-dimensional quantum material. Not only the PL intensity, but also the fundamental photoluminescence quantum yield has exhibited a huge, order-scale enhancement through suspending, even surprisingly, we found the PLQY improvement revealed far significantly under small pumping power and came out an exponential increase tendency toward even lower carrier density region. With its strong excitonic effect, suspended WSe_2 offers a solution to reduce carrier trapping and participate in non-radiative processes. Moreover, in the low-power range where SRH recombination dominates, suspended WSe_2 exhibited remarkably higher percentage of excitonic radiation compared to contacted WSe_2. Herein, we quantitatively demonstrate the significance of suspended WSe_2 monolayer at low carrier density region, highlighting its potential for developing compact, low-power quantum emitters in the future

    Apoptosis Induction in Primary Human Colorectal Cancer Cell Lines and Retarded Tumor Growth in SCID Mice by Sulforaphane

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    We have investigated the anticancer effects of the dietary isothiocyanate sulforaphane (SFN) on colorectal cancer (CRC), using primary cancer cells lines isolated from five Taiwanese colorectal cancer patients as the model for colorectal cancer. SFN-treated cells accumulated in metaphase (SFN 6.25 μM) and subG1 (SFN 12.5 and 25 μM) as determined by flow cytometry. In addition, treated cells showed nuclear apoptotic morphology that coincided with an activation of caspase-3, and loss of mitochondrial membrane potential (ΔΨm). Incubations at higher SFN doses (12.5 and 25 μM) resulted in cleavage of procaspase-3 and elevated caspase-2, -3, -8, and -9 activity, suggesting that the induction of apoptosis and the sulforaphane-induced mitosis delay at the lower dose are independently regulated. Daily SFN s.c. injections (400 micromol/kg/d for 3 weeks) in severe combined immunodeficient mice with primary human CRC (CP1 to CP5) s.c. tumors resulted in a decrease of mean tumor weight by 70% compared with vehicle-treated controls. Our findings suggest that, in addition to the known effects on cancer prevention, sulforaphane may have antitumor activity in established colorectal cancer

    Seismic behavior of pile in liquefiable soil ground by centrifuge shaking table tests

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    Dramatic failure of pile foundations caused by the soil liquefaction was founded and leading to many studies on the seismic behavior of pile. The failures were often accompanied with settlement, lateral displacement and tilting of superstructures. Therefore soil-structure interaction effects must be properly considered in the design of pile. Two centrifuge models were conducted by shaking table at an acceleration field of 80 g. The purpose of this study was to investigate the seismic response of piles attached with different tip mass and embedded in liquefied or non-liquefied deposits. From the results, it was found that the maximum bending moment of pile occurs at the depth of 4 m and 5 m for dry sand and saturated sand models, respectively. The more tip mass leads to the more permanent lateral displacement and the more residual bending moment

    Difference in the regulation of IL-8 expression induced by uropathogenic E. coli between two kinds of urinary tract epithelial cells

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    Bacterial adherence to epithelial cells is a key virulence trait of pathogenic bacteria. The type 1 fimbriae and the P-fimbriae of uropathogenic Escherichia coli (UPEC) have both been described to be important for the establishment of urinary tract infections (UTI). To explore the interactions between the host and bacterium responsible for the different environments of UPEC invasion, we examined the effect of pH and osmolarity on UPEC strain J96 fimbrial expression, and subsequent J96-induced interleukin-8 (IL-8) expression in different uroepithelial cells. The J96 strain grown in high pH with low osmolarity condition was favorable for the expression of type 1 fimbriae; whereas J96 grown in low pH with high osmolarity condition was beneficial for P fimbriae expression. Type 1 fimbriated J96 specifically invaded bladder 5637 epithelial cells and induced IL-8 expression. On the contrary, P fimbriated J96 invaded renal 786-O epithelial cells and induced IL-8 expression effectively. Type 1 fimbriated J96-induced IL-8 induction involved the p38, as well as ERK, JNK pathways, which leads to AP-1-mediated gene expression. P fimbriated J96-induced augmentation of IL-8 expression mainly involved p38-mediated AP-1 and NF-κB transcriptional activation. These results indicate that different expression of fimbriae in J96 trigger differential IL-8 gene regulation pathways in different uroepithelial cells

    Idiopathic young-onset Fahr’s disease with schizophrenia-like presentation: a case report

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    This case report describes an exceptionally rare case in which a prior diagnosis of schizophrenia was later determined to be early-onset Fahr’s disease, linked to a genetic mutation in the SLC20A2 gene. Initially, the patient exhibited symptoms resembling schizophrenia, including aggression and hostility, and was highly susceptible to medication side effects such as restlessness and Parkinsonism. Despite maintaining independent activities of daily living, his neurological examinations revealed hidden weakness on the left side. Following adjustments to the medication regimen, stability was achieved with residual psychotic symptoms under treatment with Risperidone 1.5mg/day, Valproic acid 1500mg/day, and Quetiapine 37.5mg/day. This case underscores the importance of conducting comprehensive imaging studies at the time of initial psychiatric diagnosis, regardless of the apparent typicality of the presentation. Additionally, it emphasizes the need for patience and adherence to the “Start Low and Go Slow” approach in medication management to minimize the risk of exacerbating psychiatric symptoms and aggression

    Responsiveness and construct validity of two outcome measures of bilateral upper limb function in patients with chronic stroke

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    BackgroundStroke is a leading cause of long-term disability among stroke survivors. Despite the availability of numerous stroke rehabilitative therapies, such as mirror therapy, bilateral arm training, and robot-assisted therapy, the recovery of motor function after stroke remains incomplete. Bilateral arm function is a key component in stroke patients to perform activities of daily living and to reflect their functional autonomy.ObjectiveThis clinimetric study investigated and compared the construct validity and responsiveness of 2 bimanual activity outcome measures, the Chedoke Arm and Hand Activity Inventory (CAHAI) and the ABILHAND Questionnaire, in individuals receiving stroke rehabilitation.MethodsThe present study is a secondary analysis following the framework of the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN). Individuals with chronic stroke (N = 113) were recruited from outpatient rehabilitation settings. Participants received 18 to 20 sessions of robot-assisted therapy, mirror therapy, combined therapy, or conventional rehabilitation for 4 to 6 weeks. The CAHAI, ABILHAND Questionnaire, and a comparison instrument, the Motor Activity Log (MAL), were administered twice at a 4- to 6-week interval to all participants. ABILHAND scores, in logits, were converted from raw ordinal scores into a linear measure.ResultsThere was medium to large correlation of the CAHAI and the MAL (ρ = 0.60–0.62, p < 0.01) as well as the ABILHAND Questionnaire and the MAL (ρ = 0.44–0.51, p < 0.01). Change scores from the initial measurement to the post-intervention measurement demonstrated small to medium correlation of the CAHAI and the MAL (ρ = 0.27–0.31, p < 0.01) and medium to large correlation of the ABILHAND Questionnaire and the MAL (ρ = 0.37–0.41, p < 0.01). Overall, 7 of 8 hypotheses were supported. The hypothesis testing regarding the construct validity and responsiveness of the CAHAI and ABILHAND Questionnaire was confirmed.ConclusionThe CAHAI and ABILHAND Questionnaire are both responsive and suitable to detect changes in bilateral arm functional daily activities in individuals with chronic stroke. Patient-reported outcome measures are recommended to use along with therapist-rated outcome measures for upper limb capacity evaluation in stroke rehabilitation. Further study with a prospective study design to capture specific clinical features of participants and the use of body-worn sensors, such as the arm accelerometer, is suggested

    Lack of Association between CLEC5A Gene Single-Nucleotide Polymorphisms and Kawasaki Disease in Taiwanese Children

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    Background. Kawasaki disease is characterized by systemic vasculitis of unknown etiology. Previous genetic studies have identified certain candidate genes associated with susceptibility to KD and coronary artery lesions. Host innate immune response factors are involved in modulating the disease outcome. The aim of this study was to investigate CLEC5A (C-type lectin domain family 5) genetic polymorphisms with regards to the susceptibility and outcome of KD. Methods. A total of 1045 subjects (381 KD patients and 664 controls) were enrolled to identify 4 tagging single-nucleotide polymorphisms (tSNPs) of CLEC5A (rs1285968, rs11770855, rs1285935, rs1285933) by using the TaqMan Allelic Discrimination Assay. The Hardy-Weinberg equilibrium was assessed in cases and controls, and genetic effects were evaluated by the chi-square test. Results. No significant associations were noted between the genotypes and allele frequency of the 4 CLEC5A tSNPs between controls and patients. In the patients, polymorphisms of CLEC5A showed no significant association with coronary artery lesion formation and intravenous immunoglobulin treatment response. Conclusions. This study showed for the first time that polymorphisms of CLEC5A are not associated with susceptibility to KD, coronary artery lesion formation, and intravenous immunoglobulin treatment response in a Taiwanese population

    FGF signalling controls the specification of hair placode-derived SOX9 positive progenitors to Merkel cells

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    Merkel cells are innervated mechanosensory cells responsible for light-touch sensations. In murine dorsal skin, Merkel cells are located in touch domes and found in the epidermis around primary hairs. While it has been shown that Merkel cells are skin epithelial cells, the progenitor cell population that gives rise to these cells is unknown. Here, we show that during embryogenesis, SOX9-positive (+) cells inside hair follicles, which were previously known to give rise to hair follicle stem cells (HFSCs) and cells of the hair follicle lineage, can also give rise to Merkel Cells. Interestingly, while SOX9 is critical for HFSC specification, it is dispensable for Merkel cell formation. Conversely, FGFR2 is required for Merkel cell formation but is dispensable for HFSCs. Together, our studies uncover SOX9(+) cells as precursors of Merkel cells and show the requirement for FGFR2-mediated epithelial signalling in Merkel cell specification.Peer reviewe
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