Intermetallic Cobalt Indium Nanoparticles as Oxygen Evolution Reaction Precatalyst: A Non-Leaching p-Block Element.

Merely all transition-metal-based materials reconstruct into similar oxyhydroxides during the electrocatalytic oxygen evolution reaction (OER), severely limiting the options for a tailored OER catalyst design. In such reconstructions, initial constituent p-block elements take a sacrificial role and leach into the electrolyte as oxyanions, thereby losing the ability to tune the catalyst's properties systematically. From a thermodynamic point of view, indium is expected to behave differently and should remain in the solid phase under alkaline OER conditions. However, the structural behavior of transition metal indium phases during the OER remains unexplored. Herein, are synthesized intermetallic cobalt indium (CoIn3 ) nanoparticles and revealed by in situ X-ray absorption spectroscopy and scanning transmission microscopy that they undergo phase segregation to cobalt oxyhydroxide and indium hydroxide. The obtained cobalt oxyhydroxide outperforms a metallic-cobalt-derived one due to more accessible active sites. The observed phase segregation shows that indium behaves distinctively differently from most p-block elements and remains at the electrode surface, where it can form lasting interfaces with the active metal oxo phases.

Challenges for Hybrid Water Electrolysis to Replace the Oxygen Evolution Reaction on an Industrial Scale.

To enable a future society based on sun and wind energy, transforming electricity into chemical energy in the form of fuels is crucial. This transformation can be achieved in an electrolyzer performing water splitting, where at the anode, water is oxidized to oxygen-oxygen evolution reaction (OER)-to produce protons and electrons that can be combined at the cathode to form hydrogen-hydrogen evolution reaction (HER). While hydrogen is a desired fuel, the obtained oxygen has no economic value. A techno-economically more suitable alternative is hybrid water electrolysis, where value-added oxidation reactions of abundant organic feedstocks replace the OER. However, tremendous challenges remain for the industrial-scale application of hybrid water electrolysis. Herein, these challenges, including the higher kinetic overpotentials of organic oxidation reactions compared to the OER, the small feedstock availably and product demand of these processes compared to the HER (and carbon dioxide reduction), additional purifications costs, and electrocatalytic challenges to meet the industrially required activities, selectivities, and especially long-term stabilities are critically discussed. It is anticipated that this perspective helps the academic research community to identify industrially relevant research questions concerning hybrid water electrolysis.

Clinical implantation of 92 VACStents in the upper gastrointestinal tract of 50 patients-applicability and safety analysis of an innovative endoscopic concept.

Introduction: Endoscopic vacuum therapy (EVT) has emerged as a promising treatment option for upper gastrointestinal wall defects, offering benefits such as evacuation of secretions and removal of wound debris by suction, and reduction and healing of wound cavities to improve clinical outcomes. In contrast, covered stents have a high rate of migration and lack functional drainage, while endoluminal EVT devices obstruct the GI tract. The VACStent is a novel device that combines the benefits of EVT and stent placement. Its design features a fully covered Nitinol-stent within a polyurethane sponge cylinder, enabling EVT while maintaining stent patency. Methods: This study analyzes the pooled data from three different prospective study cohorts to assess the safe practicality of VACStent placement, complete leak coverage, and effective suction-treatment of esophageal leaks. By pooling the data, the study aims to provide a broader base for analysis. Results: In total, trans-nasal derivation of the catheter, suction and drainage of secretion via vacuum pump were performed without any adversity. In the pooled study cohort of 92 VACStent applications, the mean stent indwelling time was 5.2 days (range 2-8 days) without any dislocation of the device. Removal of the VACStent was done without complication, in one case the sponge was lost but subsequently fully preserved. Minor local erosions and bleeding and one subsequent hemostasis were recorded unfrequently during withdrawal of the device (5.4%, 5/92) but no perforation or pressure ulcer. Despite a high heterogeneity regarding primary disease and pretreatments a cure rate of 76% (38/50 patients) could be achieved. Discussion: In summary, insertion and release procedure was regarded as easy and simple with a low potential of dislocation. The VACStent was well tolerated by the patient while keeping the drainage function of the sponge achieving directly a wound closure by continuous suction and improving the healing process. The implantation of the VACStent provides a promising new procedure for improved clinical treatment in various indications of the upper gastrointestinal wall, which should be validated in larger clinical studies.Clinical Trial Registration: Identifier [DRKS00016048 and NCT04884334].

Oxygen Evolution Activity of Amorphous Cobalt Oxyhydroxides: Interconnecting Precatalyst Reconstruction, Long-Range Order, Buffer-Binding, Morphology, Mass Transport, and Operation Temperature.

Nanocrystalline or amorphous cobalt oxyhydroxides (CoCat) are promising electrocatalysts for the oxygen evolution reaction (OER). While having the same short-range order, CoCat phases possess different electrocatalytic properties. This phenomenon is not conclusively understood, as multiple interdependent parameters affect the OER activity simultaneously. Herein, a layered cobalt borophosphate precatalyst, Co(H2 O)2 [B2 P2 O8 (OH)2 ]·H2 O, is fully reconstructed into two different CoCat phases. In contrast to previous reports, this reconstruction is not initiated at the surface but at the electrode substrate to catalyst interface. Ex situ and in situ investigations of the two borophosphate derived CoCats, as well as the prominent CoPi and CoBi identify differences in the Tafel slope/range, buffer binding and content, long-range order, number of accessible edge sites, redox activity, and morphology. Considering and interconnecting these aspects together with proton mass-transport limitations, a comprehensive picture is provided explaining the different OER activities. The most decisive factors are the buffers used for reconstruction, the number of edge sites that are not inhibited by irreversibly bonded buffers, and the morphology. With this acquired knowledge, an optimized OER system is realized operating in near-neutral potassium borate medium at 1.62 ± 0.03 VRHE yielding 250 mA cm-2 at 65 °C for 1 month without degrading performance.

Effect of Surface-Adsorbed and Intercalated (Oxy)anions on the Oxygen Evolution Reaction.

As the kinetically demanding oxygen evolution reaction (OER) is crucial for the decarbonization of our society, a wide range of (pre)catalysts with various non-active-site elements (e.g., Mo, S, Se, N, P, C, Si…) have been investigated. Thermodynamics dictate that these elements oxidize during industrial operation. The formed oxyanions are water soluble and thus predominantly leach in a reconstruction process. Nevertheless, recently, it was unveiled that these thermodynamically stable (oxy)anions can adsorb on the surface or intercalate in the interlayer space of the active catalyst. There, they tune the electronic properties of the active sites and can interact with the reaction intermediates, changing the OER kinetics and potentially breaking the persisting OER *OH/*OOH scaling relations. Thus, the addition of (oxy)anions to the electrolyte opens a new design dimension for OER catalysis and the herein discussed observations deepen the understanding of the role of anions in the OER.

Evolving Highly Active Oxidic Iron(III) Phase from Corrosion of Intermetallic Iron Silicide to Master Efficient Electrocatalytic Water Oxidation and Selective Oxygenation of 5-Hydroxymethylfurfural.

In a green energy economy, electrocatalysis is essential for chemical energy conversion and to produce value added chemicals from regenerative resources. To be widely applicable, an electrocatalyst should comprise the Earth's crust's most abundant elements. The most abundant 3d metal, iron, with its multiple accessible redox states has been manifold applied in chemocatalytic processes. However, due to the low conductivity of FeIII Ox Hy phases, its applicability for targeted electrocatalytic oxidation reactions such as water oxidation is still limited. Herein, it is shown that iron incorporated in conductive intermetallic iron silicide (FeSi) can be employed to meet this challenge. In contrast to silicon-poor iron-silicon alloys, intermetallic FeSi possesses an ordered structure with a peculiar bonding situation including covalent and ionic contributions together with conducting electrons. Using in situ X-ray absorption and Raman spectroscopy, it could be demonstrated that, under the applied corrosive alkaline conditions, the FeSi partly forms a unique, oxidic iron(III) phase consisting of edge and corner sharing [FeO6 ] octahedra together with oxidized silicon species. This phase is capable of driving the oxyge evolution reaction (OER) at high efficiency under ambient and industrially relevant conditions (500 mA cm-2 at 1.50 ± 0.025 VRHE and 65 °C) and to selectively oxygenate 5-hydroxymethylfurfural (HMF).

Intermetallic Fe6Ge5 formation and decay of a core-shell structure during the oxygen evolution reaction.

Herein, we report on intermetallic iron germanide (Fe6Ge5) as a novel oxygen evolution reaction (OER) precatalyst with a Tafel slope of 32 mV dec-1 and an overpotential of 272 mV at 100 mA cm-2 in alkaline media. Furthermore, we uncover the in situ formation of a core-shell like structure that slowly collapses under OER conditions.

Facile Access to an Active γ-NiOOH Electrocatalyst for Durable Water Oxidation Derived From an Intermetallic Nickel Germanide Precursor.

Identifying novel classes of precatalysts for the oxygen evolution reaction (OER by water oxidation) with enhanced catalytic activity and stability is a key strategy to enable chemical energy conversion. The vast chemical space of intermetallic phases offers plenty of opportunities to discover OER electrocatalysts with improved performance. Herein we report intermetallic nickel germanide (NiGe) acting as a superior activity and durable Ni-based electro(pre)catalyst for OER. It is produced from a molecular bis(germylene)-Ni precursor. The ultra-small NiGe nanocrystals deposited on both nickel foam and fluorinated tin oxide (FTO) electrodes showed lower overpotentials and a durability of over three weeks (505 h) in comparison to the state-of-the-art Ni-, Co-, Fe-, and benchmark NiFe-based electrocatalysts under identical alkaline OER conditions. In contrast to other Ni-based intermetallic precatalysts under alkaline OER conditions, an unexpected electroconversion of NiGe into γ-NiIII OOH with intercalated OH- /CO3 2- transpired that served as a highly active structure as shown by various ex situ methods and quasi in situ Raman spectroscopy.

A soft molecular 2Fe-2As precursor approach to the synthesis of nanostructured FeAs for efficient electrocatalytic water oxidation.

An unprecedented molecular 2Fe-2As precursor complex was synthesized and transformed under soft reaction conditions to produce an active and long-term stable nanocrystalline FeAs material for electrocatalytic water oxidation in alkaline media. The 2Fe2As-centred ß-diketiminato complex, having an unusual planar Fe2As2 core structure, results from the salt-metathesis reaction of the corresponding ß-diketiminato FeIICl complex and the AsCO- (arsaethynolate) anion as the monoanionic As- source. The as-prepared FeAs phase produced from the precursor has been electrophoretically deposited on conductive electrode substrates and shown to act as a electro(pre)catalyst for the oxygen evolution reaction (OER). The deposited FeAs undergoes corrosion under the severe anodic alkaline conditions which causes extensive dissolution of As into the electrolyte forming finally an active two-line ferrihydrite phase (Fe2O3(H2O) x ). Importantly, the dissolved As in the electrolyte can be fully recaptured (electro-deposited) at the counter electrode making the complete process eco-conscious. The results represent a new and facile entry to unexplored nanostructured transition-metal arsenides and their utilization for high-performance OER electrocatalysis, which are also known to be magnificent high-temperature superconductors.

Individual invitation letters lead to significant increase in attendance for screening colonoscopies: Results of a pilot study in Northern Hesse, Germany.

BACKGROUND: Colorectal cancer (CRC) is the second most common cancer in Germany. Screening colonoscopies are considered an effective tool for early detection and prevention of CRC and are recommended in Germany for citizens over the age of 55. To increase the participation rate for screening colonoscopies, an invitation procedure was initiated in parts of Germany for patients between the ages of 55 and 75 who had never undergone a screening colonoscopy before. METHODS: We examined the number of participating patients before, during, and after the invitation procedure and compared the number of the participating patients who received a cover letter with the participating patients from the control group. Additionally, we classified the findings of the colonoscopies including CRC, advanced adenomas, and polyps. RESULTS: During the invitation period, the participation rate of the invitation group increased from 220 patients to 531 patients compared to 1256 to 1693 in the control group. The increase was significantly greater in patients with cover letters (+141% vs.+35%, p < 0.0001). Also, significantly more polyps and adenomas were found in patients from the invitation letter group (254 (+102%) vs. 679 (-9%), p < 0.0001). CONCLUSIONS: Our study clearly indicates that personal invitation letters are an effective measure to increase overall participation rates in screening colonoscopies.

[Gender differences and inflammatory bowel disease]. / Geschlechtsspezifische Unterschiede in der Behandlungsrealität von Patientinnen und Patienten mit chronisch-entzündlichen Darmerkrankungen (CED).

This review focuses on the gender and sex dimorphic disease profile and treatment reality of patients suffering from inflammatory bowel diseases (IBD). It provides an overview of gender-specific differences in the disease course, medical and surgical therapy as well as psychosocial aspects of IBD.

Titanium-catalyzed reductive umpolung reactions with a metal-free terminal reducing agent.

A new method for titanium-catalyzed reductive umpolung reactions is reported that overcomes the traditional requirement for a stoichiometric metallic reductant. With N,N'-disilylated tetramethyldihydropyrazine as a potent organic reducing agent, reductive carbonyl-nitrile, enone-acrylonitrile and pinacol coupling reactions can be achieved in good yields and stereoselectivities. [Cp2TiI2] is a superior catalyst to [Cp2TiCl2], which is rationalized by a faster generation of the active catalyst [Cp2TiI]. A mechanism is proposed that is in agreement with the experimental results.

Subspectacular nematodiasis caused by a novel Serpentirhabdias species in ball pythons (Python regius).

Subspectacular nematodiasis was diagnosed in three captive-bred juvenile ball pythons (Python regius) from two unrelated facilities within a 6-month period. The snakes were presented with similar lesions, including swelling of facial, periocular and oral tissues. Bilaterally, the subspectacular spaces were distended and filled with an opaque fluid, which contained nematodes and eggs. Histopathology showed nematodes throughout the periocular tissue, subspectacular space and subcutaneous tissue of the head. The nematodes from both facilities were morphologically indistinguishable and most closely resembled Serpentirhabdias species. Morphological characterization and genetic sequencing indicate this is a previously undescribed rhabdiasid nematode.

Increased levels of anti-glycan antibodies in patients with cystic fibrosis.

BACKGROUND: The prevalence of Crohn's disease (CD) is increased in patients with cystic fibrosis (CF). Anti-Saccharomyces cerevisiae antibodies (ASCA) have been suggested as a screening tool to detect CD in CF. Recently, several new anti-glycan antibodies have been reported in CD. - MATERIALS AND METHODS: The sera of 119 CF patients of various age groups were prospectively screened for ASCA type IgG (gASCA), anti-laminaribioside carbohydrate IgG antibodies (ALCA), anti-chitobioside carbohydrate IgA antibodies (ACCA), and anti-mannobioside carbohydrate IgG antibodies (AMCA). The frequency of these anti-glycan antibodies was then compared in patients with CD, ulcerative colitis, rheumatoid arthritis and healthy volunteers. - RESULTS: A significant number of CF patients were positive for gASCA (51.3% (41.6-60.6)) and up to three other anti-glycan antibodies concurrently. Serum levels of anti-glycan antibodies in CF and CD were not related to parameters of inflammation. Despite the well-documented difference in clinical course between male and female CF patients no gender difference of anti-glycan antibodies was found. In contrast, there was a significant positive correlation between anti-glycan markers and age in CF patients. - CONCLUSIONS: Our findings demonstrate for the first time the increased frequency of a panel of anti-glycan antibodies in CF and provide a link between the presence of these serological biomarkers and patient's age. Anti-glycan antibody profiling may therefore become a valuable tool in the care of patients with CF.

Interfragmentary compression forces of scaphoid screws in a sawbone cylinder model.

Various screws have been developed to stabilise fractures of the scaphoid. Commonly used are the Herbert, the HBS, the 3-mm AO and the Acutrak screws. Not long ago a new screw, the Twin Fix, was introduced. This is cannulated and similar in shape and appearance to the classical Herbert screw. In our test series we compared the maximum achievable compression forces of the Twin Fix screw with that of three other screws (AO, HBS and Acutrak screws). To avoid the variations of density, stiffness and rigidity in natural bone, a polyurethane sawbone-based test setup was used. The test series included 10 screws of each type. The compression force was measured using a special strain gauge. The mean compression force was significantly higher for the Twin Fix screw (8+/-1N) and the Acutrak screw (7.6+/-0.4/0.6N) in relation to the AO screw (6.8+/-1.0/1.4N) and HBS screw (2+/-1N). We found the Twin Fix and Acutrak screws to be promising in the treatment of scaphoid fractures.

Cytotoxic T-cell response against steroidogenic acute regulatory protein using DNA vaccination followed by vaccinia virus infection in a mouse adrenal carcinoma model.

Adrenocortical carcinoma (ACC) is still one of the most devastating human tumors with a five year survival as low as 20 %. In a previous study, we showed that DNA vaccination followed by vaccinia virus was able to break immune tolerance against murine steroidogenic acute regulatory (mStAR). Prophylactic vaccination in syngenic mice resulted in protective immunity against Sp2-0 tumor cells expressing mStAR. However, approximately a third of the animals developed tumors despite vaccination. This prompted us to investigate whether vaccination failure is responsible for this phenomenon. BALB/cBALB/c mice (in groups of 6 - 9 animals) were vaccinated intramuscularly by injection of cDNA expression vectors encoding mStAR three times at weekly intervals. This was followed by a recombinant vaccinia virus (rVV-mStAR) infection to boost immune response. Ten days after the last vaccination, Sp2-mStAR or parental Sp2-0 cells (as controls) were injected s. c. Tumor development was monitored by daily palpation. Approximately two weeks later, the animals were sacrificed and the spleens removed. After restimulation with the cell lines expressing mStAR, the splenocytes were tested for presence of mStAR self-reactive cytotoxic T-lymphocytes using ELISPOT analysis. With this approach, we were able to show that those animals protected from tumor growth had a specific T-cell response against StAR whereas mice without a specific T-cell response developed Sp2-mStAR tumors. Our data demonstrate that vaccination failure, probably due to the low antigenicity of mStAR, is responsible for tumor growth in our model system.

Impact of 131I-SPECT/CT images obtained with an integrated system in the follow-up of patients with thyroid carcinoma.

PURPOSE: The purpose of the study was to determine the diagnostic impact of 131I-SPECT/CT imaging compared with conventional scintigraphic evaluation in the follow-up of patients with thyroid carcinoma. METHODS: Seventy-one patients with thyroid carcinoma underwent concurrent 131I-SPECT/CT, using an integrated imaging system, at various stages of their disease in order to evaluate foci of uptake detected on planar whole-body images. RESULTS: SPECT/CT imaging had an incremental diagnostic value in 57% (41/71) of patients. Uptake in the neck was evaluated in 61 patients, and SPECT/CT imaging in this region had an incremental diagnostic value in 27% of the whole patient population (19/71). Low-resolution integrated CT images allowed for the precise characterization of equivocal neck lesions on planar imaging in 14/17 patients and changed the assessment of the lesion location in five patients as compared with planar studies. Thirty-six patients underwent SPECT/CT for evaluation of foci of uptake distant from the neck. SPECT/CT imaging improved characterization of equivocal foci of uptake as definitely benign in 13% (9/71) of patients. Precise localization of malignant lesions to the skeleton was possible in 17% (12/71) and to the lungs versus the mediastinum in 6% (5/71) of patients. CONCLUSION: Integrated 131I-SPECT/CT was found to have an additional value over planar imaging in patients with thyroid cancer for correct characterization of equivocal tracer uptake seen on planar imaging as well as for precise localization of malignant lesions in the neck, chest, and skeleton. SPECT/CT optimized the localization of 131I uptake to lymph node metastases versus remnant thyroid tissue, to lung versus mediastinal metastases, and to the skeleton. It also had a further clinical impact on patient management by influencing referral for 131I treatment, tailoring of the administered radioiodine dose, and/or the addition of surgery or external radiation therapy when indicated.