A novel method for preparing BiOI nanoplates and their use as precursors to synthesize porous BiVO4 water oxidation photocatalysts.

In this work, we report an innovative method for synthesizing BiOI nanoplate powder by a slow basification of an aqueous solution constituted of Bi(NO3)3 and KI. The basification was done with NH3 vapor which was naturally generated on top of an NH4OH solution kept in a closed space. The impact of the basification rate on the morphology and crystallinity of the BiOI product was investigated. Herein, we also report on the use of newly produced BiOI nanoplate powder together with the VO(acac)2 precursor for fabricating BiVO4 photoanodes for solar driven water splitting applications. We also discuss how the morphology of BiOI nanoplates and their orientation on a fluorine doped tin oxide substrate will affect the morphology, topology and photocatalytic performance of the electrode. The BiVO4 photoanode showed a photocatalytic current density of 0.55 mA cm-2 at 1.23 V vs. the Reversible Hydrogen Electrode (RHE) when assayed in a pH 7 phosphate buffer electrolyte and under 1 sun illumination.

Fabrication of inverse opal molybdenum sulfide and its use as a catalyst for H2 evolution.

Amorphous molybdenum sulfide (MoSx) and crystalline molybdenum disulfide (MoS2) are attractive noble-metal-free electrocatalysts for the H2 evolution reaction from water. Their actual activities depend on the quantity of active sites which are exposed to the electrolyte, which in turn, is influenced by their specific electrochemical surface area. Herein we report on the fabrication of regular inverse opal MoSx and MoS2 films by employing polystyrene nanoparticles with diameters in the range of 30-90 nm as hard templates. The use of these catalysts for the H2 evolution reaction in an acidic electrolyte solution is also presented. Impacts of the regular porous structure, the film thickness as well as the chemical nature of the catalyst (MoS2versus MoSx) are discussed. It shows a catalytically-effective-thickness of ca. 300 nm where the electrolyte can fully penetrate the catalyst macropores, thus all the catalytic active sites can be exposed to the electrolyte to achieve the maximal catalytic operation.

[Mo2 S12 ]2- Complex as a Precursor for In-situ Generation of Molybdenum Sulfide Catalyst During the H2 Evolution.

For decades, the sulfido molybdenum complexes like [MoS4 ]2- , [Mo2 S12 ]2- , [Mo3 S13 ]2- have gained great attention because of their chemical versatility as well as their structural similarity to the edge-plan of the molybdenum disulfide (MoS2 ) which shows promising catalytic ability for the H2 generation. In this work, we report on the investigation of the dinuclear complex [Mo2 S12 ]2- in both organic and aqueous solution. We demonstrate that [Mo2 S12 ]2- is not intact during the H2 evolution catalysis when it is assayed as a homogeneous catalyst in an electrolyte solution (e. g. in DMF or water solvent) nor when it is immobilized on an electrode surface (e. g. mesoporous carbon black). It transforms into the polymeric amorphous molybdenum sulfide [MoS] which subsequently acts as an actual catalyst. We discuss on the possible [Mo2 S12 ]2- to [MoS] transformation mechanism by employing an arsenal of electrochemical analysis, spectroscopic analyses and microscopic analyses. Effects of the electrochemical operating conditions to the [Mo2 S12 ]2- to [MoS] transformation as well as to the chemical nature and the catalytic performance of the [MoS] product are also emphasized.

Water-Splitting Artificial Leaf Based on a Triple-Junction Silicon Solar Cell: One-Step Fabrication through Photoinduced Deposition of Catalysts and Electrochemical Operando Monitoring.

Solar hydrogen generation via water splitting using a monolithic photoelectrochemical cell, also called artificial leaf, could be a powerful technology to accelerate the transition from fossil to sustainable energy sources. Identification of scalable methods for the fabrication of monolithic devices and gaining insights into their operating mode to identify solutions to improve performance and stability represent great challenges. Herein, we report on the one-step fabrication of a CoWO|ITO|3jn-a-Si|Steel|CoWS monolithic device via the simple photoinduced deposition of CoWO and CoWS as oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) catalyst layers, respectively, onto an illuminated ITO|3jn-a-Si|Steel solar cell using a single-deposition bath containing the [Co(WS4)2]2- complex. In a pH 7 phosphate buffer solution, the best device achieved a solar-to-hydrogen conversion yield of 1.9%. Evolution of the catalyst layers and that of the 3jn-a-Si light-harvesting core during the operation of the monolithic device are examined by conventional tools such as scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and inductively coupled plasma optical emission spectroscopy (ICP-OES) together with a bipotentiostat measurement. We demonstrate that the device performance degrades due to the partial dissolution of the catalyst. Still, this degradation is healable by simply adding [Co(WS4)2]2- to the operating solution. However, modifications on the protecting indium-doped tin oxide (ITO) layer are shown to initiate irreversible degradation of the 3jn-a-Si light-harvesting core, resulting in a 10-fold decrease of the performances of the monolithic device.

Comparison of automated total nucleated cell counts vs manual cell counts in the amniotic fluid for the classification of disease status in healthy and diseased pigs.

BACKGROUND: An increase in the total nucleated cell count (TNCC) of amniotic fluid can detect inflammation in the amniotic cavity. Traditionally, a manual count is employed, but the technique suffers from inaccuracy and is labor intensive. Automated cell counting could enhance precision and timeliness. OBJECTIVES: We aimed to analyze the cell counts in the amniotic fluid of preterm pigs using an automated method and compared the results with manual cell counts. We also tested if increased TNCC is associated with an inflammatory group in a porcine model of chorioamnionitis. METHODS: Amniotic fluids from 34 preterm pigs were analyzed blindly using two automatic settings of the ADVIA 2120i hematology analyzer (whole blood [WB] and cell poor [CP] settings) and manually by two observers using Neubauer chambers. Inter- and intra-variability were calculated. The correlation analysis of TNCC/µL in amniotic fluid was determined between the methods, including Deming and Bland-Altman analyses. Fischer's exact tests compared the known health status of the pigs to the outcomes of the automatic and manual TNCC. RESULTS: Inter- and intra-observer variability of the manual TNCC were high, although the correlation of TNCC between (r = .95, P < .0001) and within observers (r = .98, P < .0001; r = .89, P < .0001) was good. Correlation between the manual and CP TNCC was moderate and significant (r = .50, P = .014). Manual and WB TNCC were not correlated. The CP (P = .003) and manual (P = .0001) analyses accurately classified the disease state of the pigs. CONCLUSIONS: An acceptable correlation between automatic CP TNCC and manual counting was demonstrated. Both methods could accurately classify the disease state of the pigs.

Gold nanoparticles as an outstanding catalyst for the hydrogen evolution reaction.

An electrode made of Au nanoparticles, ca. 13 nm in diameter, displays outstanding catalytic activity for the hydrogen evolution reaction in water. At an overpotential of 200 mV it operates with a catalytic rate TOF of 0.3 s-1, which is among the best performances ever achieved for a Pt-free H2-evolving catalyst.

Disulfide-Bridged (Mo3S11) Cluster Polymer: Molecular Dynamics and Application as Electrode Material for a Rechargeable Magnesium Battery.

Exploring novel electrode materials is critical for the development of a next-generation rechargeable magnesium battery with high volumetric capacity. Here, we showed that a distinct amorphous molybdenum sulfide, being a coordination polymer of disulfide-bridged (Mo3S11) clusters, has great potential as a rechargeable magnesium battery cathode. This material provided good reversible capacity, attributed to its unique structure with high flexibility and capability of deformation upon Mg insertion. Free-terminal disulfide moiety may act as the active site for reversible insertion and extraction of magnesium.

[Intracranial haemorrhage due to decompensationof hypertension in severe preeclampsia with the needof a hysterectomy - case report]. / Intrakraniální krvácení v dusledku dekompenzace hypertenze pri závazné preeklampsii s nutností provedení hysterektomie - kazuistika.

OBJECTIVE: To present a case of intracranial haemorrhage due to decompensated hypertension in case of severe preeclampsia which resulted in acute caesarean section followed by hysterectomy. DESIGN: Case report. SETTING: Department of Obstetrics and Gynaecology, Hospital Kladno. CASE REPORT: We report the case of a 36-year old multiparous woman in the 35th week of pregnancy with no prenatal care. According to her medical history, she had a caesarean section three years earlier and six previous spontaneous deliveries without complications (including spontaneously delivered twins). She underwent three abortions and one spontaneous miscarriage. This patient arrived to our department in serious condition with critical values of blood pressure, strong headache, impaired vision, dysarthria and right hemiparesis. In cooperationwith a neurologist we performed an acute native brain CT which revealed an acute intracranial haemorrhage. According to the neurosurgeon, this finding was not suitable for neurosurgical intervention. The patient was indicated for acute caesarean section. Due to heavy bleeding during the caesarean section, a hysterectomy was performed. CONCLUSION: In presenting this serious case of preeclampsia, the authors want to emphasize the need for early diagnosis, interdisciplinary cooperation, sufficient treatment and knowledge of surgical interventions such as abdominal hysterectomy, as a final solution for a life-threatening perinatal haemorrhage.

Effects of N-acetylcysteine on microalbuminuria and organ failure in acute severe sepsis: results of a pilot study.

STUDY OBJECTIVE: The level of microalbuminuria is thought to reflect the severity of inflammation-induced systemic vascular permeability and may have prognostic value with regard to organ dysfunction and survival. N-acetylcysteine (NAC) has been shown to decrease capillary leakage in experimental sepsis. The present study investigated the effect of early treatment with NAC on microalbuminuria and organ dysfunction in severe clinical sepsis. DESIGN: Prospective, randomized, placebo-controlled study. SETTING: A 24-bed multidisciplinary ICU in a university teaching hospital. PATIENTS: Thirty-five patients included within 4 h of fulfilling consensus criteria of severe sepsis. INTERVENTIONS: Patients were randomly assigned to receive either NAC (continuous infusion starting with 50 mg/kg/4 h followed by 100 mg/kg/24 h for 44 h; n = 18) or placebo (n = 17) in addition to standard therapy. MEASUREMENTS AND RESULTS: Urine samples for measurement of microalbuminuria/creatinine ratio (MACR) were collected on inclusion and after 4 h, 24 h, and 48 h. Severity of illness and degree of organ failure were determined by using, respectively, the APACHE (acute physiology and chronic health evaluation) II score and the sequential organ failure assessment (SOFA) score. The MACR did not differ over time between the placebo- and the NAC-treated groups. SOFA scores were comparable between both treatment groups at baseline (6.2 +/- 3.9 vs 6.5 +/- 2.7, NAC vs placebo; p = 0.6) and increased during treatment in the NAC-treated patients but not in the placebo group (7.9 +/- 3.7 vs 5.9 +/- 2.5, p = 0.09 and 7.7 +/- 3.8 vs 5.1 +/- 2.1, p < 0.05; NAC vs placebo, respectively, at 24 h and at 48 h). The cardiovascular SOFA score progressively increased during NAC treatment, reaching higher values as compared to time-matched scores in the placebo group. CONCLUSIONS: Early NAC administration does not influence the course of MACR in severe clinical sepsis, suggesting that NAC might not attenuate endothelial damage in this condition. NAC treatment even aggravated sepsis-induced organ failure, in particular cardiovascular failure.

The evolution of serum astroglial S-100 beta protein in patients with cardiac arrest treated with mild hypothermia.

OBJECTIVE: To study the effects of mild hypothermia on the 24h concentration of serum astroglial of S-100 beta protein in patients who survived cardiac arrest (CA). DESIGN: A prospective, randomised, clinical study in a university teaching hospital. PATIENTS: Sixty-one resuscitated patients were randomised into two prospective studies, known as the short study period (SSP) (n = 33 patients) and the long study period (LSP) (n = 28 patients). In the SSP study, patients older than 18 years of age and surviving asystole or pulseless electrical activity were included. In the LSP study, patients with ventricular fibrillation (VF) or non-perfusing ventricular tachycardia (VT) aged between 18 and 75 years were included. In each of the study groups, the patients were further randomised into either normothermic or hypothermic subgroups. The standard supportive therapy was similar, only the devices used to reduce the body temperature and the period of hypothermia were different. Serum samples for the measurement of astroglial S-100 beta protein were collected at admission and 24h later. RESULTS: During the first 24h after the cardiac arrest, the concentration of astroglial serum S-100 beta protein decreased significantly in the hypothermic cohort. In the normothermic cohort, the decrease of serum astroglial S-100 beta protein was less pronounced and even increased in the normothermic LSP group. CONCLUSION: Induced mild hypothermia reduced the 24h astroglial serum S-100 beta protein concentration and might play a neuroprotective effect after cardiac arrest.