Well incorporation of carbon nanodots with silicon nanowire arrays featuring excellent photocatalytic performances.

Recently, silicon (Si) nanowires have been intensively applied for a wide range of optoelectronic applications. Nevertheless, rare explorations considering the photodegradation of organic pollutants based on Si nanowires were performed, and they still require vast improvement, in particular for their degradation efficiency. In this study, broad-band and high efficiency photocatalytic systems were demonstrated through the good incorporation of Si nanowires with highly fluorescent carbon nanodots. The photodegradation rate of these intriguing heterostructure arrays under a 580 nm light illumination is approximately 6 times higher than that of sole Si nanowires, and more than 3.6 and 4.5 times higher than that of Si nanowire incorporated with silver and gold nanoparticles, respectively. Optimizing the luminescent behaviors of carbon nanodots leads to the involvement of multiple light sources that activate the photoexcitation of carriers within the Si nanowires. This feature was further elucidated by examining the corresponding photocurrents under light illumination, which presents currents 1.9 times higher than those with the sole Si nanowires. In combination with excellent wettability with dye solutions, the present heterostructured nanowire arrays have promised the robust photocatalytic capability with retained efficiency after cycling uses, which may open up unique opportunities for future pollutant detoxification and wastewater treatment.

Reactive oxygen species mediate Terbufos-induced apoptosis in mouse testicular cell lines via the modulation of cell cycle and pro-apoptotic proteins.

Terbufos (S-t-butylthiomethyl-O,O-diethyl phosphorodithioate) is a highly toxic organophosphate which is extensively used as an insecticide and nematicide. Chronic exposure to terbufos causes neuronal injury and predisposes to neurodegenerative diseases. Accumulating evidence has shown that the exposure to terbufos, as an occupational risk factor, may also cause reproductive disorders. However, the exact mechanisms of reproductive toxicity remain unclear. The present study aimed to investigate the toxic effect of terbufos on testicular cells and to explore the mechanism of toxicity on a cellular level. The cytotoxic effects of terbufos on mouse immortalized spermatogonia (GC-1), spermatocytes (GC-2), Leydig (TM3), and Sertoli (TM4) cell lines were assessed by MTT assays, caspase activation, flow cytometry, TUNEL assay, Western blot, and cell cycle analysis. The exposure to different concentrations of terbufos ranging from 50 to 800 µM for 6 h caused significant death in all the used testicular cell lines. Terbufos increased reactive oxygen species (ROS) production, reduced mitochondrial membrane potential, and initiated apoptosis, which was confirmed by a dose-dependent increase in the number of TUNEL-positive apoptotic cells. Blocking ROS production by N-acetyl cysteine (NAC) protected GC-1 cells from terbufos-induced cell death. The results demonstrated that terbufos induces ROS, apoptosis, and DNA damage in testicular cell lines and it should be considered potentially hazardous to testis. Together, this study provided potential molecular mechanisms of terbufos-induced toxicity in testicular cells and suggests a possible protective measure. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1888-1898, 2016.

Silver-assisted chemical etching on silicon with polyvinylpyrrolidone-mediated formation of silver dendrites.

Metal-assisted chemical etching (MaCE) on silicon (Si)-mediated by polyvinylpyrrolidone (PVP)-is systematically investigated herein. It is found that the morphologies and crystallographic natures of the grown silver (Ag) dendrites can be significantly modulated, with the presence of PVP in the MaCE process leading to the formation of faceted Ag dendrites preferentially along the (111) crystallographic phase, rather than along the (200) phase. Further explorations of the PVP-mediated effect on Si etching are also revealed. In contrast to the aligned Si nanowires formed by MaCE without PVP addition, only distributed nanopores with sizes of 200 to 400 nm appear on the Si surfaces in the presence of PVP. The origin of surface polishing on Si in the PVP-mediated MaCE process can be attributed to the distinct transport pathway of holes supplied by the Ag(+) ions, where the holes are injected directly into the primary Ag seeds, rather than through Ag dendrites, thus leading to the isotropic etching of the Si surface.

Efficacy and safety of acupuncture for dizziness and vertigo in emergency department: a pilot cohort study.

BACKGROUND: Dizziness and vertigo account for roughly 4% of chief symptoms in the emergency department (ED). Pharmacological therapy is often applied for these symptoms, such as vestibular suppressants, anti-emetics and benzodiazepines. However, every medication is accompanied with unavoidable side-effects. There are several research articles providing evidence of acupuncture treating dizziness and vertigo but few studies of acupuncture as an emergent intervention in ED. We performed a pilot cohort study to evaluate the efficacy and safety of acupuncture in treating patients with dizziness and vertigo in ED. METHODS: A total of 60 participants, recruited in ED, were divided into acupuncture and control group. Life-threatening conditions or central nervous system disorders were excluded to ensure participants' safety. The clinical effect of treating dizziness and vertigo was evaluated by performing statistical analyses on data collected from questionnaires of Dizziness Handicap Inventory (DHI), Visual Analog Scale (VAS) of dizziness and vertigo, and heart rate variability (HRV). RESULTS: The variation of VAS demonstrated a significant decrease (p-value: 0.001 and p-value: 0.037) between two groups after two different durations: 30 mins and 7 days. The variation of DHI showed no significant difference after 7 days. HRV revealed a significant increase in high frequency (HF) in the acupuncture group. No adverse event was reported in this study. CONCLUSION: Acupuncture demonstrates a significant immediate effect in reducing discomforts and VAS of both dizziness and vertigo. This study provides clinical evidence on the efficacy and safety of acupuncture to treat dizziness and vertigo in the emergency department. TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT02358239 . Registered 5 February 2015.

Exploring the kinetics of ordered silicon nanowires with the formation of nanogaps using metal-assisted chemical etching.

Actual dimension control of silicon (Si) nanowire arrays was conducted using metal-assisted chemical etching on Si patterned by electron beam lithography. The appearance of nanogaps at the edge of each nanowire provides the diffusion pathways of reactants for Si dissolution, predominantly causing distinct etching rates that depend upon the spacings of nanogaps.

Fluorinated photoreduced graphene oxide with semi-ionic C-F bonds: An effective carbon based photocatalyst for the removal of volatile organic compounds.

There is much interest in developing metal-free halogenated graphene such as fluorinated graphene for various catalytic applications. In this work, a fluorine-doped graphene oxide photocatalyst was investigated for photocatalytic oxidation (PCO) of a volatile organic compound (VOC), namely gaseous methanol. The fluorination process of graphene oxide (GO) was carried out via a novel and facile solution-based photoirradiation method. The fluorine atoms were doped on the surface of the GO in a semi-ionic C-F bond configuration. This presence of the semi-ionic C-F bonds induced a dramatic 7-fold increment of the hole charge carrier density of the photocatalyst. The fluorinated GO photocatalyst exhibited excellent photodegradation up to 93.5% or 0.493 h-1 according pseudo-first order kinetics for methanol. In addition, 91.7% of methanol was mineralized into harmless carbon dioxide (CO2) under UV-A irradiation. Furthermore, the photocatalyst demonstrated good stability in five cycles of methanol PCO. Besides methanol, other VOCs such as acetone and formaldehyde were also photodegraded. This work reveals the potential of fluorination in producing effective graphene-based photocatalyst for VOC removal.

Prevalence of uveitis in syphilis patients in Taiwan.

Few population-based studies have looked at the risk of uveitis among syphilis patients. Our study addresses the knowledge gap by reporting on uveitis risk in syphilis patients through a retrospective cohort study. The Taiwan National Health Insurance database was used for this study, covering the period from January 1st, 2009, to December 31st, 2020. We created a 1:4 propensity score matched cohort between the syphilis patients and controls, which accounted for gender, age, and comorbidities. The primary endpoint was the incidence of newly recorded uveitis. The assessment of uveitis risk in syphilis patients included the use of the Kaplan-Meier method and multivariate Cox proportional hazard model. A total of 31,597 syphilis patients and 126,379 matched comparisons were recruited. The uveitis incidence rate from our syphilis patients was 1.25 per 1000 person-years. The uveitis incidence rate from our non-syphilis group was 0.8 per 1000 person-years. After matching, the syphilis group was found to have a higher risk of developing uveitis (adjusted hazard ratio (aHR) [95% CI]: 1.57 [1.36-1.81], P < .001). Among males and individuals aged 20-34 years, subgroup analysis showed an increased risk of uveitis in the presence of syphilis infection. The Kaplan-Meier survival curve showed a significant difference in uveitis incidence between syphilis and non-syphilis groups (log-rank test P < .001). In summary, our study revealed that Taiwanese syphilis patients were at a higher risk of developing uveitis. These results highlight the need for regular ocular monitoring and screening in individuals with syphilis.

Influences of textured substrates on the heart rate of developing zebrafish embryos.

Identification of the effects of different textured substrates on zebrafish (Danio rerio) embryos provides insights into the influence of external stimuli on normal cardiovascular functions in the developmental stages of the embryos. This knowledge can be used in numerous genetic studies using zebrafish as an animal model as well as in bioanalytical assays using digital microfluidics. In this study, zebrafish embryos were systematically positioned and in vivo imaged on four types of silicon substrates. These substrates exhibited surface textures and surface wettability that were well modulated by wet chemical etching. The heart rate of the developing embryos significantly increased by 9.1% upon exposure to textured Si substrates with nanostructured surfaces compared with bare Si substrates. Modulation of surface wettability in the tested substrates also responded to the increase in the heart rate of the embryo; however, the effect of surface wettability on heart rate was slight compared with the effect of texture. In-depth experimental and statistical investigations of heart rate under the effects of substrate textures imply a pathway through which the inner mass of the embryo reacts to external stimuli. These findings contribute to zebrafish-related studies and suggest other factors to consider in the design of nanostructure-based microfluidics and other biomedical devices.

Balance of photon management and charge collection from carbon-quantum-dot layers as self-powered broadband photodetectors.

Semiconductor colloidal quantum dots (QDs) have been regarded as promising fluorescent materials for chemical sensing, bio-detection and optical communications; yet it still remains challenging to bring out self-powered photodetectors based solely on QDs because the excited charges within QDs are extremely immobile due to their reduced dimensionalities and they hardly form effective photocurrents. Hence, we have attempted to decouple the light-absorption and charge-transport criteria in order to feature highly-sensitive, rapid-response and self-driven photodetectors based on single-layer carbon QD layers (CQDLs) via facile in situ self-assembling deposition with fine control over thickness. We show explicit dark-current suppression by visualizing charge blocking phenomena and screen effects due to layered CQDL structures, which alleviate the movement of leakage carriers crossing over the CQD interlayers. By examining the distribution of electric fields within CQDLs under light excitation, the spatial dependence of the light-trapping effect within CQDLs was confirmed. These features are strongly associated with the thickness tuning of CQDLs, while 65 nm of CQDL thickness could manifest remarkable photoresponsivity above 9.4 mA W-1 and detectivity above 5.9 × 1012 under broadband light illumination. These results demonstrate the insights gained from an understanding of broadband optoelectronics, which might potentially pave the way for further employment in functional photodetection.

Delaminated MnPS3 with Multiple Layers Coupled with Si Featuring Ultrahigh Detectivity and Environmental Stability for UV Photodetection.

Silicon (Si), the dominant semiconductor in microelectronics yet lacking optoelectronic functionalities in UV regions, has been researched extensively to make revolutionary changes. In this study, the inherent drawback of Si on optoelectronic functionalities in UV regions is potentially overcome through heterostructure coupling of delaminated p-type MnPS3, having bulk, multiple-layer, and few-layer features, with n-type Si. By artificially mimicking the architectures of shrubs with unique UV shading phenomena, the revolutionary multiple-layer MnPS3 structures with staggered stacking configurations trigger outstanding UV photosensing performances, displaying an average EQE value of 1.1 × 103%, average photoresponsivity of 3.1 × 102 A/W, average detectivity of 1.9 × 1014 cm Hz1/2W1-, and average on/off ratio of 1.8 × 103 under 365 nm light. To the best of our knowledge, this is the first attempt toward realizing gate-free MnPS3-based UV photodetectors, while all of the photodetection outcomes are better than those of more sophisticated field-effect transistor (FET) designs, which have remarkable impacts on the practicality and functionality of next-generation UV optoelectronics.

Ultra-Broadband High-Entropy Oxide Absorber Layer for Enhanced Photodetector Performance.

A novel light-absorbing material of high-entropy oxide (HEO) has been synthesized using the hydrothermal method. The HEO has six metals, namely, Fe, Ni, Mn, Cr, Mg, and Cu. The obtained HEO light absorber is demonstrated to show unprecedented broadband absorption, ranging from 310 to 1400 nm. The photodetector having a structure of Ag/HEO/n-Si has been evaluated for its performance. Under the illumination of various light wavelengths, the photodetector exhibits a remarkably wide range of photoresponse from 365 to 1050 nm, giving wide-spectrum photocurrent densities in the order of 1 mA/cm2, a responsibility as high as 3.5 A/W (850 nm), and an external quantum efficiency (EQE) of more than 700% (850 nm), outperforming all of the reported oxide-based photodetectors. The superior device performance is attributed to the excellent light absorbance and EQE of the oxygen vacancy-containing HEO. Moreover, a number of tests, including the abrasion test, temperature endurance, acidic resistance, on-off switching cycling, and 3 dB bandwidth measurement, show the excellent reliability of the obtained HEO-based photodetector.

Acupuncture for ventilator-dependent patients at a hospital-based respiratory care center: A randomized controlled trial.

Background: In intensive care units, mechanical ventilation is an important therapy to help patients with dyspnea. However, long-term ventilator dependence would consume huge medical resources and increase the risk of morbidity and mortality. The aim of the study was to examine the efficacy of the acupuncture combined with western medical care on ventilator parameters in ventilator-dependent patients. Methods: In this clinical trial, 80 ventilator-dependent patients aged 20 to 80 years old were randomly assigned to acupuncture group and control group in the respiratory care center (RCC) of Changhua Christian Hospital. Besides regular medical care and therapy, participants in the acupuncture group received acupuncture therapy at the same 17 acu-points for 20 minutes once a day, a total of 12 sessions. The ventilator parameters were recorded to evaluate the respiratory efficiency for all participants. The primary outcome was rapid shallow breathing index (RSBI), and secondary outcomes were respiratory rate (RR), tidal volume (TV) and ventilation per minute (MV). Results: Though there was no significant difference in the parameter between the acupuncture group and the control group, we found the trend of decreasing RSBI in the acupuncture group. In subgroup analyses, the mean of RSBI significantly decreased 16.02 (with the SD in 60.84) in acupuncture group, while it increased 17.84 (with the SD in 39.38) in control group (p=0.036) after 12 sessions. Conclusion: Acupuncture treatment can improve breathing ability of patients with respirator dependence in respiratory care center.

Association between immune checkpoint inhibitor medication and uveitis: a population-based cohort study utilizing TriNetX database.

Objective: To explore the associations between the use of immune checkpoint inhibitors (ICIs) and the risk of developing uveitis among cancer patients. Methods: Cancer patients who received ICI therapy and a comparison group of cancer patients who did not receive ICI therapy were retrospectively recruited from the TriNetX electronic heath-record registry. The outcome of interest was the development of new-onset uveitis. Propensity score matching based on a 1:1 ratio was conducted in order to reduce bias. Multi-variate cox proportional hazard models and Kaplan Meier method were also utilized to assess for the risk of uveitis among cancer patients who received ICI therapy. Results: 71931 cancer patients (54.7% male; 76.5% white; mean age at index 63.6 ± 12.2 years) who received ICI treatment (ICI group) and 71931 cancer patients (54.7% male; 77% white; mean age at index 63.5 ± 12.4 years) who never received ICI (comparison group) were recruited. Associated Kaplan-Meier curves showed significantly increased uveitis risk among the ICI group for all follow-up years (p<0.001). The risk of uveitis was also higher among the ICI group during the 144-month follow-up period with a hazard ratio (HR) of 2.39 (95% CI: 2.07-2.75). Increased risk for specific uveitis diseases, such as iridocyclitis, chorioretinal inflammation, retinal vasculitis, unspecified purulent endophthalmitis, pan-uveitis and sympathetic uveitis were found. Subgroup analysis demonstrated an elevated hazard ratio for the development of uveitis among ICI recipients, spanning individuals below the age of 65 as well as those aged 65 and older. The elevated hazard ratio for uveitis development among ICI recipients was also observed across all genders, among those of white and Asian ethnicities, those with smoking history, and those with comorbid conditions such as hypertension and dyslipidemia, in comparison to their non-ICI counterparts. An additional subgroup analysis on monotherapy versus combinatory ICI regimens was also conducted. Individuals who received monotherapy from the class of anti-PD-1 (HR:1.98 [CI: 1.65-2.37]) and anti-CTLA-4 (HR:5.86 [CI:1.99-17.24]) exhibited elevated hazard ratios for uveitis development compared to their non-ICI comparators. Those exposed to combinatory ICI regimens, specifically a combination of anti-PD-1 and anti-CTLA4 (HR: 5.04 [CI:3.55-7.16]), showed increased hazard ratios for uveitis development compared to their non-ICI comparators. In contrast, individuals exposed to a combination of anti-PD-1 and anti-PD-L1 (HR: 2.47 [CI:0.81-7.50]) did not demonstrate an increased risk for uveitis compared to their non-ICI comparators. Conclusion: A significantly increased risk for uveitis diseases was found among the ICI group from the first year of follow-up. Increased awareness should be promoted on the occurrence of uveitis among cancer patients receiving ICI therapy.

Inducing transparency with large magnetic response and group indices by hybrid dielectric metamaterials.

We present metamaterial-induced transparency (MIT) phenomena with enhanced magnetic fields in hybrid dielectric metamaterials. Using two hybrid structures of identical-dielectric-constant resonators (IDRs) and distinct-dielectric-constant resonators (DDRs), we demonstrate a larger group index (ng~354), better bandwidth-delay product (BDP~0.9) than metallic-type metamaterials. The keys to enable these properties are to excite either the trapped mode or the suppressed mode resonances, which can be managed by controlling the contrast of dielectric constants between the dielectric resonators in the hybrid metamaterials.

Tailoring broadband antireflection on a silicon surface through two-step silver-assisted chemical etching.

Combined nanostructure arrays with tailored structural profiles are presented (see picture, GN: graded nanostructure). These arrays exhibit a sharp decrease in reflectivity when submitted to strong sunlight irradiation, showing great potential for diverse applications, such as optical and electro-optical devices and other antireflection designs.

Photocatalytic decolorization of Remazol Black 5 and Remazol Brilliant Orange 3R by mesoporous TiO2.

Mesoporous TiO2 microparticles (TiO2-11) were prepared through the micelle hydrothermal method using a 1:1 M ratio of 1-tetradecylamine:Ti(OiPr)4. TiO2-11 microparticles exhibited significantly higher decolorization percentage of Remazol Black 5 (RB5) and Remazol Brilliant Orange (3R) dyes than other TiO2 microparticles formed with different molar ratios of 1-tetradecylamine:Ti(OiPr)4, and P25 and anatase TiO2. The results showed that the decolorization of the dyes by the microparticles was affected by the different irradiation wavelengths, catalyst dosages, dye concentrations, initial pH values, as well as electron acceptors. The kinetic experiments with varying initial pH values were in accordance with the second-order model. In addition, the adsorption study of the dyes in the dark fitted well with the Langmuir isotherm model. With the addition of 20 mmol/mL of three electron acceptors, H2O2, KBrO3, and (NH4)2S2O8, the decolorization of the RB5 and 3R dyes increased by 54% and 35%, 59% and 41%, and 36% and 33%, respectively. Hence, this technique for the preparation of the mesoporous TiO2 microparticles can facilitate more efficient decolorization of dyes in an aqueous solution.

Light Trapping of Inclined Si Nanowires for Efficient Inorganic/Organic Hybrid Solar Cells.

Light/matter interaction of low-dimensional silicon (Si) strongly correlated with its geometrical features, which resulted in being highly critical for the practical development of Si-based photovoltaic applications. Yet, orientation modulation together with apt control over the size and spacing of aligned Si nanowire (SiNW) arrays remained rather challenging. Here, we demonstrated that the transition of formed SiNWs with controlled diameters and spacing from the crystallographically preferred <100> to <110> orientation was realized through the facile adjustment of etchant compositions. The underlying mechanism was found to correlate with the competing reactions between the formation and removal of oxide at Ag/Si interfaces that could be readily tailored through the concentration ratio of HF to H2O2. By employing inclined SiNWs for the construction of hybrid solar cells, the improved cell performances compared with conventional vertical-SiNW-based hybrid cells were demonstrated, showing the conversion efficiency of 12.23%, approximately 1.12 times higher than that of vertical-SiNW-based hybrid solar cells. These were numerically and experimentally interpreted by the involvement of excellent light-trapping effects covering the wide-angle light illuminations of inclined SiNWs, which paved the potential design for next-generation optoelectronic devices.

Day-night active photocatalysts obtained through effective incorporation of Au@CuxS nanoparticles onto ZnO nanowalls.

Photocatalytic degradation of organic dyes has been considered one of the promising solutions that enabled to effectively treat the demanding pollutants in wastewater. Yet, insight into the photocatalytic process under both illumination and dark conditions were hitherto missing. Herein, by virtue of incorporating the core-shell Au@CuxS nanoparticles to the ZnO nanowalls synthesized via all-solution synthesis, the intriguing heterostructures allowed to trigger the extraordinary capability of dye degradation either under light irradiance or dark environment. It was found that the coexistence of bi-constituted Cu2S/CuS shells on Au nanoparticles obtained with turning the concentrations of sulfurization acted as the decisive role on day-night active degradation performance, where the degradation efficiency was more than 8.3 times beyond sole ZnO sheets. The mediation of remarkable visible-light absorption and efficient charge separation due to band alignment of heterojunctions were responsible for the improved photodegradation efficiency under visible illuminations. Moreover, at dark environment, the involving peroxidase-like activity of CuxS shells with the mediation of Au nanoparticles facilitated the catalytic formation of hydroxyl radicals, manifesting the oxidative degradation of MB dye. Such all-day active photocatalysts further displayed the capability for the recycling treatment of MB dye, which offered the pathways to potentially treat the organic wastewater.

Unveiling the detection kinetics and quantitative analysis of colorimetric sensing for sodium salts using surface-modified Au-nanoparticle probes.

Rapid, reliable, and sensitive colorimetric detection has been regarded as a highly potential technique for visually monitoring the cation ions. Yet, insight into detection kinetics and quantitative analysis for colorimetric sensing of sodium ions has rarely been revealed. Herein, in-depth kinetic investigations of colorimetric detection using surface-modified Au-nanoparticle (AuNP) probes were performed for interpreting the correlation of salt concentration, reaction duration, and light absorbance. To envision these undisclosed issues, modification of AuNP surfaces with ascorbic acid was found to be highly essential for boosting the detection sensitivity due to adjusting the zeta potential of AuNP colloids towards a slightly positive value. Next, modeling the light absorbance of AuNPs under various aggregation circumstances was employed, which visually elucidated the color change so that it was visible to the naked eye, due to the intense field localization on the edges of aggregated AuNPs. In addition, the involved activation energy of AuNP aggregation was found to follow the first-order Arrhenius formula, with the extracted value of 22.5 kJ mol-1. Finally, quantitative visualization of colorimetric Na+ ion sensing was realized, and the experimental relation was obtained for explicitly determining the unknown concentration of Na+ ions in a visual manner.

Visual Cu2+ Detection of Gold-Nanoparticle Probes and its Employment for Cu2+ Tracing in Circuit System.

Highly sensitive, simple and reliable colorimetric probe for Cu2+-ion detection was visualized with the L-cysteine functionalized gold nanoparticle (LS-AuNP) probes. The pronounced sensing of Cu2+ with high selectivity was rapidly featured with obvious colour change that enabled to visually sense Cu2+ ions by naked eyes. By employing systemic investigations on crystallinities, elemental compositions, microstructures, surface features, light absorbance, zeta potentials and chemical states of LS-AuNP probes, the oxidation-triggered aggregation effect of LS-AuNP probes was envisioned. The results indicated that the mediation of Cu2+ oxidation coordinately caused the formation of disulfide cystine, rendering the removal of thiol group at AuNPs surfaces. These features reflected the visual colour change for the employment of tracing Cu2+ ions in a quantitative way.