V-doped activated Ru/Ti2.5V0.5C2 dual-active center accelerate hydrogen production from ammonia borane.

Designing and constructing the active center of Ru-based catalysts is the key to efficient hydrolysis of ammonia borane (NH3BH3, AB) for hydrogen production. Herein, V-doped Ru/Ti2.5V0.5C2 dual-active center catalysts were synthesized, showing excellent catalytic ability for AB hydrolysis. The corresponding turnover frequency value was 1072 min-1 at 298 K, and the hydrolysis rate rB of AB was 235 × 103 mL·min-1·gRu-1. X-ray photoelectron spectroscopy results indicated that the interaction between V-doped Ti3C2 and catalytic metal Ru transfers electrons from Ti to Ru, resulting in electron-rich Ru species. According to density functional theory calculations, the activation energy and reaction dissociation energy of the reactants AB and H2O on V-doped catalysts were lower than those of Ru/Ti3C2, thus optimizing the catalytic kinetics of AB hydrolysis. The modification strategy of V-doped Ti3C2 provides a new pathway for the development of high-performance catalysts for AB hydrolysis.

Valproate-related hyperammonemic encephalopathy with generalized suppression EEG: a case report.

BACKGROUND: Valproic acid (VPA) is a prevalent antiseizure medication (ASM) used to treat epilepsy. Valproate-related hyperammonemic encephalopathy (VHE) is a type of encephalopathy that can occur during neurocritical situations. In VHE, the electroencephalogram (EEG) displays diffuse slow waves or periodic waves, and there is no generalized suppression pattern. CASE PRESENTATION: We present a case of a 29-year-old female with a history of epilepsy who was admitted for convulsive status epilepticus (CSE), which was controlled by intravenous VPA, as well as oral VPA and phenytoin. The patient did not experience further convulsions but instead developed impaired consciousness. Continuous EEG monitoring revealed a generalized suppression pattern, and the patient was unresponsive. The patient's blood ammonia level was significantly elevated at 386.8 µmol/L, indicating VHE. Additionally, the patient's serum VPA level was 58.37 µg/ml (normal range: 50-100 µg/ml). After stopping VPA and phenytoin and transitioning to oxcarbazepine for anti-seizure and symptomatic treatment, the patient's EEG gradually returned to normal, and her consciousness was fully restored. DISCUSSION: VHE can cause the EEG to display a generalized suppression pattern. It is crucial to recognize this specific situation and not to infer a poor prognosis based on this EEG pattern.

Supported Nanostructured MoxC Materials for the Catalytic Reduction of CO2 through the Reverse Water Gas Shift Reaction.

MoxC-based catalysts supported on γ-Al2O3, SiO2 and TiO2 were prepared, characterized and studied in the reverse water gas shift (RWGS) at 548-673 K and atmospheric pressure, using CO2:H2 = 1:1 and CO2:H2 = 1:3 mol/mol reactant mixtures. The support used determined the crystalline MoxC phases obtained and the behavior of the supported nanostructured MoxC catalysts in the RWGS. All catalysts were active in the RWGS reaction under the experimental conditions used; CO productivity per mol of Mo was always higher than that of unsupported Mo2C prepared using a similar method in the absence of support. The CO selectivity at 673 K was above 94% for all the supported catalysts, and near 99% for the SiO2-supported. The MoxC/SiO2 catalyst, which contains a mixture of hexagonal Mo2C and cubic MoC phases, exhibited the best performance for CO production.

Design and Optimization of a Pressure Sensor Based on Serpentine-Shaped Graphene Piezoresistors for Measuring Low Pressure.

This thesis describes a novel microelectromechanical system (MEMS) piezoresistive pressure sensor based on serpentine-shaped graphene piezoresistors paired with trapezoidal prisms under the diaphragm for measuring low pressure. The finite element method (FEM) is utilized to analyze the mechanical stress and membrane deflection to enhance the degree of stress concentration in this unique sensor. The functional relationship between mechanical performance and dimension variables is established after using the curve fitting approach to handle the stress and deflection. Additionally, the Taguchi optimization method is employed to identify the best dimensions for the proposed structure. Then, the suggested design is compared to the other three designs in terms of operating performance. It is revealed that the recommended sensor can significantly improve sensitivity while maintaining extremely low nonlinearity. In this study, three different types of serpentine-shaped graphene piezoresistors are also designed, and their sensing capability is compared to silicon. The simulation results indicate that the pressure sensor with Type 2 graphene piezoresistors has a maximum sensitivity of 24.50 mV/psi and ultra-low nonlinearity of 0.06% FSS in the pressure range of 0-3 psi.

Stabilized cobalt-based nanofilm catalyst prepared using an ionic liquid/water interfacial process for hydrogen generation from sodium borohydride.

The design and construction of transition metal catalysts with high performance and low-cost characteristics are imperative for liquid hydrogen storage materials. In this study, we prepared ultrathin carbon-stabilized Co-doped CoxOy nanofilms (C-Co/CoxOy NFs) using an ionic liquid/water interface strategy for sodium borohydride (NaBH4) hydrolysis. Owing to its two-dimensional (2D) NF structure and the protective effects of the composite carbon, the C-Co/CoxOy NF catalyst exhibited remarkable activity and durability for hydrogen generation from NaBH4 hydrolysis. The hydrogen generation rate reached 8055 mL·min-1·gCo-1 (5106 mL·min-1·gCat-1) and the catalyst could be recycled more than 20 times, surpassing most reported metal-based catalysts under comparable conditions. In addition, the exceptional 2D Co-based NF structures, with numerous active sites, assisted in the activation of NaBH4 and water molecules, promoting hydrogen production. Thus, these results provided an in-depth understanding of hydrogen generation from NaBH4 hydrolysis, and an effective strategy for rationally designing highly active and durable 2D NF catalysts.

Enhancing Effect of Fe2+ Doping of Ni/NiO Nanocomposite Films on Catalytic Hydrogen Generation.

Highly active and stable non-noble metal catalysts are expected to play a critical role in future hydrogen storage and conversion applications. The design of active sites with composite oxides provides a new approach for developing high-performance catalysts. In this study, an Fe-doped Ni/NiO nanocomposite film was constructed on an ionic liquid/water interface to promote hydrogen generation. The optimized Ni/FeNiOx-25 catalyst showed excellent catalytic activity toward ammonia borane hydrolysis, with a turnover frequency of 72.3 min-1. The enhancing effect of Fe2+ doping on Ni/NiO films was confirmed by the improved intrinsic activity and theoretical simulations. Fe ion doping stabilized NiO and prevented NiO from becoming Ni. The interfacial Ni-Fe2+ dual active sites on the FeNiOx and Ni interfaces participated in the targeted adsorption and effective activation of water and NH3BH3 molecules, respectively. The sufficiently exposed plane surface of the nanofilms provided abundant active sites for catalytic reactions. This significant advance will inspire development in the ambient liquid hydrogen storage field.

Application of back-propagation artificial neural network and curve estimation in pharmacokinetics of losartan in rabbit.

In order to develop pharmacokinetic model, a well-known multilayer feed-forward algorithm back-propagation artificial neural networks (BP-ANN) was applied to the pharmacokinetics of losartan in rabbit. The plasma concentrations of losartan in twelve rabbits, which were divided into two groups and given losartan 2 mg/kg by intravenous (Iv) and intragastrical (Ig) administration, were determined by LC-MS. The BP-ANN model included one input layer, hidden layers, and one output layer was constructed and compared with curve estimation based on the time-concentration data of losartan. The results showed the BP-ANN model had high goodness of fit index and good coherence (R > 0.99) between forecasted concentration and measured concentration both in Iv and Ig administration. The residuals of each concentrations generated by BP-ANN model were all smaller than Curve estimation. The pharmacokinetic result showed there was no significant difference between measured and simulated pharmacokinetic parameters including AUC(0-t), AUC(0-∞), MRT(0-t), MRT(0-∞), T1/2 V and Cmax (P > 0.05). In conclusion, the BP-ANN model has remarkably accurate predictions ability, which better than Curve estimation, and can be used as a utility tool in pharmacokinetic experiment.

Enhancing field emission performance of aligned Si nanowires via in situ partial oxidization.

Partially oxidized Si nanowire (NW) arrays have been achieved via a combinatorial process of selectively etching Si wafer to obtain vertically aligned single crystalline Si NW arrays and subsequent in situ partially oxidizing the as-etched bare Si NWs. The resultant Si products are Si-SiOx nanocable-like structures consisting of single-crystalline Si NW inner cores and outer shells of insulating SiOx. Field emission measurements demonstrate that surface partial oxidization enhances the field emission current of the as-etched bare Si NWs effectively, which can be ascribed to the outer shell of insulating SiOx that has small electron affinity (0.6-0.8 eV) and can protect Si NW inner cores. The results indicate that the partially oxidized Si NW arrays would act as the excellent field emitters in the future vacuum micro- and nano-electronic devices.

The effect of apigenin on pharmacokinetics of imatinib and its metabolite N-desmethyl imatinib in rats.

The purpose of this study was to determine the effect of apigenin on the pharmacokinetics of imatinib and N-desmethyl imatinib in rats. Healthy male SD rats were randomly divided into four groups: A group (the control group), B group (the long-term administration of 165 mg/kg apigenin for 15 days), C group (a single dose of 165 mg/kg apigenin), and D group (a single dose of 252 mg/kg apigenin). The serum concentrations of imatinib and N-desmethyl imatinib were measured by HPLC, and pharmacokinetic parameters were calculated using DAS 3.0 software. The parameters of AUC(0-t), AUC(0-∞), Tmax, V(z)/F, and CL(z)/F for imatinib in group B were different from those in group A (P < 0.05). Besides, MRT(0-t) and MRT(0-∞) in groups C and D differed distinctly from those in group A as well. The parameters of AUC(0-t) and Cmax for N-desmethyl imatinib in group C were significantly lower than those in group A (P < 0.05); however, compared with groups B and D, the magnitude of effect was modest. Those results indicated that apigenin in the short-term study inhibited the metabolism of imatinib and its metabolite N-desmethyl imatinib, while in the long-term study the metabolism could be accelerated.

Effect of hypoglycemic anti-deafness capsules in diabetic patients with deafness and toxicological assessment in rats.

OBJECTIVE: Through experiment on animals and clinical trials to explore the safety and efficacy of hypoglycemic anti-deafness capsules on diabetic patients with deafness. METHODS: Total 296 patients with non-insulin dependent diabetes mellitus (NIDDM) were randomly divided into two groups. A treatment group of 164 patients (208 ears) was treated with hypoglycemic anti-deafness capsules based on TCM syndrome differentiation. A control group of 132 patients (184 ears) was treated with glibenclamide and conventional drug treatment for deafness. The following were observed: hearing, fasting plasma glucose (FPG), 2 h postprandial plasma glucose (2hPG), 24 h urine glucose (24hUG), improvement of main symptoms, platelet function, and changes in superoxide dismutase (SOD) and lipid peroxide (LPO) levels. In animal studies, Kunming mice, weighing 18-22 g were used. Half of the mice were males and half were females. Wistar rats, weighing 80-120 g were used. Half of the rats were males and half were females. Male Wistar rats, weighing 200-220 g, were also used. Their acute and chronic toxicity was studied. RESULTS: The hearing improvement was 56.7% in the treatment group and 26.6% in the control group. FPG, 2hPG, and 24hUG were improved significantly (P < 0.05, P < 0.01, P < 0.01, respectively) in the treatment group and 2hPG and 24hUG improved significantly in the control group (P < 0.05, P < 0.05). The improvement in 2hPG and 24hUG in the treatment group was significantly greater than that in the control group P < 0.01).There was no significant difference in FPG between the two groups (P < 0.05). Main symptoms in the treatment group were significantly more improved than those in the control group (P < 0.05, P < 0.01). In the treatment group, platelet adhesion and aggregation, SOD, and LPO were all significantly improved from before treatment (P < 0.05, P < 0.01). However, in the control group, except LOP (P < 0.05), there were no significant differences from before treatment to after (P < 0.05). In animal studies, no obvious acute or long-term toxicity was observed from capsule administration. CONCLUSION: Through experiment on animals and clinical trials, we can found that hypoglycemic anti-deafness capsules could decrease blood glucose and serum triglycerides of alloxan-induced diabetic rats. This herbal capsule is effective for safely treating diabetic patients with deafness.

Can contrast effects regulate emotions? A follow-up study of vital loss decisions.

Although many studies focus on the how contrast effects can impact cognitive evaluations, the question of whether emotions are regulated by such contrast effects is still the subject of considerable debate, especially in the study of loss-related decisions. To address this gap in the literature, we designed three decision making loss conditions: (i) both losses are trivial (TT), (ii) one loss is trivial and the other loss is vital (TV), or (iii) one loss is trivial and the other loss is routine (TR). In study 1, which compared the difference between the negative emotion ratings in TT and TV, we found that negative emotions were affected by the contrast effects. In study 2, which compared the difference between the importance of trivial options in TT and TV, we found that the contrast effects differentially changed the importance of trivial options in the two conditions, which in turn down-regulated negative emotions. In study 3, the impact of decision difficulty was controlled by predetermining the items to be lost. In this study, we found that, when comparing the differences between the negative emotions of losing trivial options in TV and TR, the contrast effects still modulated the loss-related emotions. We concluded that the contrast effects could down-regulate emotions. To our knowledge, this is the first demonstration that contrast effects can alleviate negative affect in loss-related decision making. This study will enrich and extend the literature on emotion regulation theory, and it will provide a new cost-effective mitigation strategy for regulating negative emotions.

Do you know where your fingers have been? Explicit knowledge of the spatial layout of the keyboard in skilled typists.

Two experiments evaluated skilled typists' ability to report knowledge about the layout of keys on a standard keyboard. In Experiment 1, subjects judged the relative direction of letters on the computer keyboard. One group of subjects was asked to imagine the keyboard, one group was allowed to look at the keyboard, and one group was asked to type the letter pair before judging relative direction. The imagine group had larger angular error and longer response time than both the look and touch groups. In Experiment 2, subjects placed one key relative to another. Again, the imagine group had larger angular error, larger distance error, and longer response time than the other groups. The two experiments suggest that skilled typists have poor explicit knowledge of key locations. The results are interpreted in terms of a model with two hierarchical parts in the system controlling typewriting.

Effect of illumination intensity and light application time on secondary organic aerosol formation from the photooxidation of alpha-pinene.

Secondary organic aerosol (SOA) formation from hydroxyl radical (OH*) initiated photooxidation of alpha-pinene was investigated in a home-made smog chamber. The size distribution of SOA particles was measured using aerodynamic particle sizer spectrometer. The effects of illumination intensity and light application time on SOA formation for alpha-pinene were evaluated. Experimental results show that the concentration of SOA particles increased significantly with an increasing of illumination intensity, and the light application time, the concentration, and the size of SOA particles were also increased. In addition, the factors influencing the formation of SOA were discussed. In addition, this article compared the effect of alpha-pinene with that of toluene, and discussed the contribution of alpha-pinene to SOA formation.

Dissociative photoionization of isoprene: experiments and calculations.

Vacuum ultraviolet (VUV) dissociative photoionization of isoprene in the energy region 8.5-18 eV was investigated with photoionization mass spectroscopy (PIMS) using synchrotron radiation (SR). The ionization energy (IE) of isoprene as well as the appearance energies (AEs) of its fragment ions C(5)H(7) (+), C(5)H(5) (+), C(4)H(5) (+), C(3)H(6) (+), C(3)H(5) (+), C(3)H(4) (+), C(3)H(3) (+) and C(2)H(3) (+) were determined with photoionization efficiency (PIE) curves. The dissociation energies of some possible dissociation channels to produce those fragment ions were also determined experimentally. The total energies of C(5)H(8) and its main fragments were calculated using the Gaussian 03 program and the Gaussian-2 method. The IE of C(5)H(8), the AEs for its fragment ions, and the dissociation energies to produce them were predicted using the high-accuracy energy model. According to our results, the experimental dissociation energies were in reasonable agreement with the calculated values of the proposed photodissociation channels of C(5)H(8).

Layout geometry in encoding and retrieval of spatial memory.

Two experiments investigated whether the spatial reference directions that are used to specify objects' locations in memory can be solely determined by layout geometry. Participants studied a layout of objects from a single viewpoint while their eye movements were recorded. Subsequently, participants used memory to make judgments of relative direction (e.g., "Imagine you are standing at X, facing Y, please point to Z"). When the layout had a symmetric axis that was different from participants' viewing direction, the sequence of eye fixations on objects during learning and the preferred directions in pointing judgments were both determined by the direction of the symmetric axis. These results provide further evidence that interobject spatial relations are represented in memory with intrinsic frames of reference.

Chemical composition and size distribution of secondary organic aerosol formed from the photooxidation of isoprene.

Photooxidation of isoprene leads to the formation of secondary organic aerosol (SOA). In this study, the chemical composition of SOA formed from OH-initiated photooxidation of isoprene has been investigated with gas chromatography/mass spectrometry (GC/MS) and a home-made aerosol time-of-flight mass spectrometer. Sampling particles generated in a home-made smog chamber. The size distribution of SOA particles was detected by a TSI 3321 aerodynamic particle size spectrometer in real time. Results showed that SOA created by isoprene photooxidation was predominantly in the form of fine particles, which have diameters less than 2.5 microm. The obtained mass spectra of individual particles show that products of the OH-initiated oxidation of isoprene contain methyl vinyl ketone, methacrolein, formaldehyde, and some other hydroxycarbonyls. The possible reaction mechanisms leading to these products were also discussed.