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The application of Zn compounds as buffer layers was recently extended to wide-gap CuInS2 (CIS) based thin-film solar cells. Using an alternative chemical deposition route for the buffer preparation aiming at the deposition of a single-layer, nominal ZnS buffer without the need for any toxic reactants such as hydrazine has helped us to achieve a similar efficiency as respective CdS-buffered reference devices. After identifying the deposited Zn compound, as ZnS/Zn(S,O) bilayer buffer in former investigations [M. Bär et al., J. Appl. Phys. 99, 123503 (2006)], this time the focus lies on potential diffusion/intermixing processes at the buffer/absorber interface possibly, clarifying the effect of the heat treatment, which drastically enhances the device performance of respective final solar cells. The interface formation was investigated by x-ray photoelectron and x-ray excited Auger electron spectroscopy. In addition, photoelectron spectroscopy (PES) measurements were also conducted using tunable monochromatized synchrotron radiation in order to gain depth-resolved information. The buffer side of the buffer/absorber heterointerface was investigated by means of the characterization of Zn(S,O)/ZnS/CIS structures where the ZnS/Zn(S,O) bilayer buffer was deposited successively by different deposition times. In order to make the (in terms of PES information depth) deeply buried absorber side of the buffer/absorber heterointerface accessible for characterization, in these cases the buffer layer was etched away by dilute HClaq. We found indications that while (out-leached) Cu from the absorber layer forms together with the educts in the chemical bath a [Zn(1-Z),Cu2Z]S-like interlayer between buffer and absorber, Zn is incorporated in the uppermost region of the absorber. Both effects are strongly enhanced by postannealing the Zn(S,O)/ZnS/CIS samples. However, it was determined that the major fraction of the Cu and Zn can be found quite close to the heterointerface in the buffer and absorber layer, respectively. Due to this limited (in the range of one monolayer) spatial extent, these “diffusion” mechanisms were rather interpreted as a chemical bath deposition induced and heat-treatment promoted Cu-Zn ion exchange at the buffer/absorber interface. Possible impacts of this intermixing on the performance of the final solar cell devices will also be discussed. [ABSTRACT FROM AUTHOR]

A set of samples, where an alternate Zn-compound buffer is deposited during different deposition times on CuIn[S.sub.2] (CIS)/Mo/glass absorber substrates, are characterized by x-ray photoelectron spectroscopy (XPS) and x-ray excited Auger electron spectroscopy (XAES) in order to investigate the growth mechanism of the buffer in terms of its composition. No major changes of the findings after a postannealing of the buffer/CIS sample series and recharacterization are identified.

Bacterial endosymbionts of eukaryotic hosts typically experience massive genome reduction, but the underlying evolutionary processes are often obscured by the lack of free-living relatives. Endomicrobia, a family-level lineage of host-associated bacteria in the phylum Elusimicrobiota that comprises both free-living representatives and endosymbionts of termite gut flagellates, are an excellent model to study evolution of intracellular symbionts. We reconstructed 67 metagenome-assembled genomes (MAGs) of Endomicrobiaceae among more than 1,700 MAGs from the gut microbiota of a wide range of termites. Phylogenomic analysis confirmed a sister position of representatives from termites and ruminants, and allowed to propose eight new genera in the radiation of Endomicrobiaceae . Comparative genome analysis documented progressive genome erosion in the new genus Endomicrobiellum , which comprises all flagellate endosymbionts characterized to date. Massive gene losses were accompanied by the acquisition of new functions by horizontal gene transfer, which led to a shift from a glucose-based energy metabolism to one based on sugar phosphates. The breakdown of glycolysis and many anabolic pathways for amino acids and cofactors in several subgroups was compensated by the independent acquisition of new uptake systems, including an ATP/ADP antiporter, from other gut microbiota. The putative donors are mostly flagellate endosymbionts from other bacterial phyla, including several, hitherto unknown lineages of uncultured Alphaproteobacteria , documenting the importance of horizontal gene transfer in the convergent evolution of these intracellular symbioses. The loss of almost all biosynthetic capacities in some lineages of Endomicrobiellum suggests that their originally mutualistic relationship with flagellates is on its decline.IMPORTANCEUnicellular eukaryotes are frequently colonized by bacterial and archaeal symbionts. A prominent example are the cellulolytic gut flagellates of termites, which harbor diverse but host-specific bacterial symbionts that occur exclusively in termite guts. One of these lineages, the so-called Endomicrobia, comprises both free-living and endosymbiotic representatives, which offers the unique opportunity to study the evolutionary processes underpinning the transition from a free-living to an intracellular lifestyle. Our results revealed a progressive gene loss in energy metabolism and biosynthetic pathways, compensated by the acquisition of new functions via horizontal gene transfer from other gut bacteria, and suggest the eventual breakdown of an initially mutualistic symbiosis. Evidence for convergent evolution of unrelated endosymbionts reflects adaptations to the intracellular environment of termite gut flagellates., Competing Interests: The authors declare no conflict of interest.

Designing healthcare facilities and their processes is a complex task which influences the quality and efficiency of healthcare services. The ongoing demand for healthcare services and cost burdens necessitate the application of analytical methods to enhance the overall service efficiency in hospitals. However, the variability in healthcare processes makes it highly complicated to accomplish this aim. This study addresses the complexity in the patient transport service process at a German hospital, and proposes a method based on process mining to obtain a holistic approach to recognise bottlenecks and main reasons for delays and resulting high costs associated with idle resources. To this aim, the event log data from the patient transport software system is collected and processed to discover the sequences and the timeline of the activities for the different cases of the transport process. The comparison between the actual and planned processes from the data set of the year 2020 shows that, for example, around 36% of the cases were 10 or more minutes delayed. To find delay issues in the process flow and their root causes the data traces of certain routes are intensively assessed. Additionally, the compliance with the predefined Key Performance Indicators concerning travel time and delay thresholds for individual cases was investigated. The efficiency of assignment of the transport requests to the transportation staff are also evaluated which gives useful understanding regarding staffing potential improvements. The research shows that process mining is an efficient method to provide comprehensive knowledge through process models that serve as Interactive Process Indicators and to extract significant transport pathways. It also suggests a more efficient patient transport concept and provides the decision makers with useful managerial insights to come up with efficient patient-centred analysis of transportation services through data from supporting information systems., (© 2022 The Authors. The International Journal of Health Planning and Management published by John Wiley & Sons Ltd.)

We show that platinum displays a self-adjusting surface that is active for the hydrogenation of acetone over a wide range of reaction conditions. Reaction kinetics measurements under steady-state and transient conditions at temperatures near 350 K, electronic structure calculations employing density-functional theory, and microkinetic modeling were employed to study this behavior over supported platinum catalysts. The importance of surface coverage effects was highlighted by evaluating the transient response of isopropanol formation following either removal of the reactant ketone from the feed, or its substitution with a similarly structured species. The extent to which adsorbed intermediates that lead to the formation of isopropanol were removed from the catalytic surface was observed to be higher following ketone substitution in comparison to its removal, indicating that surface species leading to isopropanol become more strongly adsorbed on the surface as the coverage decreases during the desorption experiment. This phenomenon occurs as a result of adsorbate-adsorbate repulsive interactions on the catalyst surface which adjust with respect to the reaction conditions. Reaction kinetics parameters obtained experimentally were in agreement with those predicted by microkinetic modeling when the binding energies, activation energies, and entropies of adsorbed species and transition states were expressed as a function of surface coverage of the most abundant surface intermediate (MASI, C 3 H 6 OH*). It is important that these effects of surface coverage be incorporated dynamically in the microkinetic model (e.g., using the Bragg-Williams approximation) to describe the experimental data over a wide range of acetone partial pressures., Competing Interests: Competing interest statement: J.A.D. and J.Q.B. hold patents in common. The patents are unrelated to this work.

An atomic-level understanding of dioxygen activation on metal oxides remains one of the major challenges in heterogeneous catalysis. By performing a thorough surface-science study of all three low-index single-crystal surfaces of ceria, probably the most important redox catalysts, we provide a direct spectroscopic characterization of reactive dioxygen species at defect sites on the reduced ceria (110) and (100) surfaces. Surprisingly, neither of these superoxo and peroxo species was found on ceria (111), the thermodynamically most stable surface of this oxide. Applying density functional theory, we could relate these apparently inconsistent findings to a sub-surface diffusion of O vacancies on (111) substrates, but not on the less-closely packed surfaces. These observations resolve a long standing debate concerning the location of O vacancies on ceria surfaces and the activation of O 2 on ceria powders., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Ceria (CeO 2 ) has recently been found to be a promising catalyst in the selective hydrogenation of alkynes to alkenes. This reaction occurs primarily on highly dispersed metal catalysts, but rarely on oxide surfaces. The origin of the outstanding activity and selectivity observed on CeO 2 remains unclear. In this work, we show that one key aspect of the hydrogenation reaction-the interaction of hydrogen with the oxide-depends strongly on the presence of O vacancies within CeO 2 . Through infrared reflection absorption spectroscopy on well-ordered CeO 2 (111) thin films and density functional theory (DFT) calculations, we show that the preferred heterolytic dissociation of molecular hydrogen on CeO 2 (111) requires H 2 pressures in the mbar regime. Hydrogen depth profiling with nuclear reaction analysis indicates that H species stay on the surface of stoichiometric CeO 2 (111) films, whereas H incorporates as a volatile species into the volume of partially reduced CeO 2-x (111) thin films (x ∼ 1.8-1.9). Complementary DFT calculations demonstrate that oxygen vacancies facilitate H incorporation below the surface and that they are the key to the stabilization of hydridic H species in the volume of reduced ceria.

Density functional theory is used for periodic models of monomeric vanadia species deposited on the CeO2(111) surface to study dissociative adsorption of methanol and its subsequent dehydrogenation to formaldehyde. Dispersion-corrected PBE+U calculations are performed and compared with HSE and B3LYP results. Dissociative adsorption of methanol at different sites on VO2·CeO2(111) is highly exothermic with adsorption energies of 1.8 to 1.9 eV (HSE+D). Two relevant pathways for desorption of formaldehyde are found with intrinsic barriers for the redox step of 1.0 and 1.4 eV (HSE+D). The calculated desorption temperatures (370 and 495 K) explain the peaks observed in temperature-programmed desorption experiments. Different sites of the supported catalyst system are involved in the two pathways: (i) methanol can chemisorb on the CeO2 surface filling a so-called pseudovacancy and the H atom is transferred to an V-O-Ce interphase bond or (ii) CH3OH may chemisorb at the V-O-Ce interphase bond and form a V-OCH3 species from which H is transferred to the ceria surface, providing evidence for true cooperativity. In both cases, ceria is directly involved in the redox process, as two electrons are accommodated in Ce f states forming two Ce(3+) ions whereas vanadium remains fully oxidized (V(5+)).

By virtue of periodic density functional theory, we investigate structure and thermodynamic stability of (VO)k and (VO2)k (k = 1, 2, 3) clusters deposited on the CeO2(111) surface, which serve as models for the very active sub-monolayer vanadia catalyst on a ceria support. We find V always completely oxidized (oxidation state +5) and coordinated to four O atoms. As a consequence, Ce4+ is (partially) reduced to Ce3+. Thus, localized Ce-4f states are populated, which requires an onsite U-term (PBE+U) to avoid over-delocalization off-electrons. Importantly, trimers of VO2 were found to be extraordinarily stable (agglomeration energy: -1.68 eV), whereas aggregation of VO species on CeO2(111) is thermodynamically clearly unfavourable (agglomeration energy: 3.45 eV). As a consequence a large area of the VnOm phase diagram (for relevant temperatures) is dominated by the VO2 trimer. The latter is less active towards reduction/oxidation than the active monomer and dimer of VO2, which are not present in the phase diagram at all, although directly observed by recent STM measurements. This suggests that kinetic effects hinder VO2 to grow into larger oligomers. The lowest migration energy barrier we found is as high as 1.95 eV, which indicates that adsorbed monomeric VO2 is "kinetically locked" at low temperatures and explains why monomers are stabilized on the ceria surface.

The drug development of new anti-cancer agents is streamlined in response to the urgency of bringing effective drugs to market for patients with limited life expectancy. FDA's regulation of oncology drugs has evolved from the practices set forth in Arnold Lehman's seminal work published in the 1950s through the current drafting of a new International Conference on Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) safety guidance for anti-cancer drug nonclinical evaluations. The ICH combines the efforts of the regulatory authorities of Europe, Japan, and the United States and the pharmaceutical industry from these three regions to streamline the scientific and technical aspects of drug development. The recent development of new oncology drug classes with novel mechanisms of action has improved survival rates for some cancers but also brings new challenges for safety evaluation. Here we present the legacy of Lehman and colleagues in the context of past and present oncology drug development practices and focus on some of the current issues at the center of an evolving harmonization process that will generate a new safety guidance for oncology drugs, ICH S9. The purpose of this new guidance will be to facilitate oncology drug development on a global scale by standardizing regional safety requirements.

Bridging the gap between high-vacuum soft X-ray absorption spectroscopy and real systems under ambient conditions probes chemical reactions in situ during deposition and annealing processes. The origin of highly efficient buffer layers in Zn(S,O) is the complex formation between Zn(2+) and the S=C group of thiourea (see schematic), which allows ligand-to-metal and metal-to-ligand charge transfer (LMCT and MLCT).

Rhinocerebral zygomycosis is usually an aggressive, fulminant and, at times, fatal disease most often affecting poorly controlled diabetics of all ages. We report the case of a 13-month-old white boy, a previously undiagnosed diabetic. He came to our hospital with recurrent epistaxis, decreasing consciousness, and a small visible infection at the inner canthus of the left eye. Initial evaluation revealed that the patient was in diabetic ketoacidosis. Despite aggressive medical and surgical treatment, his condition deteriorated rapidly, including the development of diabetes insipidus, and he died 4 days after admission. At autopsy, he was found to have fungal cerebritis (Rhizopus) with multiple areas of infarction and massive cerebral edema.

A case of dacryocystitis due to Mycobacterium fortuitum is reported with secondary chronic granulomatous abscess of the eyelid. Mycobacterium fortuitum is an atypical Mycobacterium rarely encountered in ophthalmic practice. The clinical course of the abscess caused by Mycobacterium is reviewed and the successful management of this problem by cryotherapy discussed.

For the determination of amylase activity and number of isoamylases in the parotid saliva of persons without diseases of the salivary glands, we investigated the saliva of 90 subjects who had been divided into 3 groups of 30 individuals each (up to 30 years, 31 to 60 years, 61 years and older). Within each group the sex ratio was 1:1. Although the amylase activities reveal no age-dependent differences, the number of isoamylases increases with age, the highest number being found only in the age group over 61 years. The possible diagnostic value of the determination of amylase activity and distribution of isoamylases is discussed.