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This database compiles comprehensive occurrence information, based on voucher specimens of small-eared shrews, genusCryptotis, that occur from México to Peru. The database integrates the information obtained from four main sources: natural history museums, public databases, fieldwork and scientific literature. It contains 3,639 records from 53 species in 12 countries. Of the total, 83.54% have collecting dates, 51.36% of the specimens are sexed and 84.56% have decimal degrees coordinates. By generating this database and making it publicly available, we hope to improve the biological knowledge of this group of small mammals still poorly studied in the region. It aims to be a valuable resource for students, researchers, conservationists and decision-makers. The dataset contains information on all species of the genusCryptotisin the Neotropical Region (namely from México to Peru), incorporating the most updated taxonomic and nomenclatural changes. The database includes records in regions and countries that are poorly represented in currently available data repositories. Most records have verified temporal and spatial information. 

Abstract Heterotrophic microbes are central to organic matter degradation and transformation in marine sediments. Currently, most investigations of benthic microbiomes do not differentiate between processes in the porewater and on the grains and, hence, only show a generalized picture of the community. This limits our understanding of the structure and functions of sediment microbiomes. To address this problem, we fractionated sandy surface sediment microbial communities from a coastal site in Isfjorden, Svalbard, into cells associated with the porewater, loosely attached to grains, and firmly attached to grains; we found dissimilar bacterial communities and metabolic activities in these fractions. Most (84%–89%) of the cells were firmly attached, and this fraction comprised more anaerobes, such as sulfate reducers, than the other fractions. The porewater and loosely attached fractions (3% and 8%–13% of cells, respectively) had more aerobic heterotrophs. These two fractions generally showed a higher frequency of dividing cells, polysaccharide (laminarin) hydrolysis rates, and per-cell O2 consumption than the firmly attached cells. Thus, the different fractions occupy distinct niches within surface sediments: the firmly attached fraction is potentially made of cells colonizing areas on the grain that are protected from abrasion, but might be more diffusion-limited for organic matter and electron acceptors. In contrast, the porewater and loosely attached fractions are less resource-limited and have faster growth. Their cell numbers are kept low possibly through abrasion and exposure to grazers. Differences in community composition and activity of these cell fractions point to their distinct roles and contributions to carbon cycling within surface sediments. 

A combination of several in situ techniques (XRD, XAS, AP-XPS, and E-TEM) was used to explore links between the structural and chemical properties of a Cu@TiOx catalyst under CO2 hydrogenation conditions. The active phase of the catalyst involved an inverse oxide/metal configuration, but the initial core@shell motif was disrupted during the pretreatment in H2. As a consequence of strong metal–support interactions, the titania shell cracked, and Cu particles migrated from the core to on top of the oxide with the simultaneous formation of a Cu–Ti–Ox phase. The generated Cu particles had a diameter of 20–40 nm and were decorated by small clusters of TiOx (<5 nm in size). Results of in situ XAS and XRD and images of E-TEM showed a very dynamic system, where the inverse oxide/metal configuration promoted the reactivity of the system toward CO2 and H2. At room temperature, CO2 oxidized the Cu nanoparticles (CO2,gas → COgas + Ooxide) inducing a redistribution of the TiOx clusters and big modifications in catalyst surface morphology. The generated oxide overlayer disappeared at elevated temperatures (>180 °C) upon exposure to H2, producing a transient surface that was very active for the reverse water–gas shift reaction (CO2 + H2 → CO + H2O) but was not stable at 200–350 °C. When oxidation and reduction occurred at the same time, under a mixture of CO2 and H2, the surface structure evolved toward a dynamic equilibrium that strongly depended on the temperature. Neither CO2 nor H2 can be considered as passive reactants. In the Cu@TiOx system, morphological changes were linked to variations in the composition of metal-oxide interfaces which were reversible with temperature or chemical environment and affected the catalytic activity of the system. The present study illustrates the dynamic nature of phenomena associated with the trapping and conversion of CO2. 

Explorations on the knowledge and biodiversity of Philippine lichen fungi have progressed recently. However, comparatively little attention has been given to the species composition along a lowland secondary forest ecosystem. Thus, the study aimed to provide information on the occurrence of lichen species in relation to various land use types of Mt. Musuan of Mindanao Island, surrounded by forest fragments and cultivated agricultural areas. A series of transect walks and opportunistic sampling revealed a total of 38 lichen species distributed in 26 genera and 14 families. Among the land use types, the mixed species forest harbors the highest recorded species with 22, followed by teak forest and built-up (peak/summit) with 15 and 14 species, respectively. Lichens with the most represented families were revealed to be Graphidaceae with 10 species; Caliciaceae with six species; Physciaceae, Parmeliaceae, and Arthoniaceae with three species each; and Pyrenulaceae, Collemataceae, Letrouitiaceae, and Trypetheliaceae with two species each. Out of these collections, two species – viz. Letrouitia subvulpina (Nyl.) Hafellner and Pyrenula globifera (Eschw.) Aptroot – were new records in the Philippines. The results of this study will provide information to encourage effective management and biodiversity conservation efforts of various land use types, as lichens are sensitive to anthropogenic threats and pressures from environmental conditions. 

Pyrenocarpous lichens are an important component of the forest ecosystem, yet remain understudied. Following the recent field surveys of the lichen biota in Mt. Musuan, four pyrenolichen species previously unreported from the Philippines were collected, namely: Porina exocha, Pyrenula pyrenuloides, P. subsoluta, and Nigrovothelium inspersotropicum. Each species is briefly described with morphology and chemistry, distribution, ecology, notes, and illustrations. These collections underscore the need for expanded research attention to fully catalogue the lichen diversity in the Philippines. 

Abstract A first integrative survey of the genusUsneain the southern Philippines, taking into account morphological, anatomical, chemical and molecular characters, resulted in the recognition of 20 taxa, including three species new to science:Usnea angulataAch.,U. baileyi(Stirt.) Zahlbr.,U. bismolliusculaZahlbr.,U. brasiliensis(Zahlbr.) Motyka,U. confusaAsah.,U. croceorubescensStirt.,U. dasaeaStirt.,U. himalayanaC. Bab.,U. krogianaP. Clerc,U. longissimaAch.,U. nidificaTaylor,U. norsticornutaA. Gerlach & P. Clerc sp. nov. (characterized by a moderately thick cortex and by the presence of norstictic acid),U. paleograndisoraA. Gerlach & P. Clerc sp. nov. (characterized by an orange subcortical pigmentation in the medulla, with enlarging soralia and a moderately thick and shiny cortex),U. pectinataTaylor,U. pygmoidea(Asahina) Y. Ohmura,U. rubicundaStirt.,U. rubrotincta(Stirt.) Zahlbr.,U. spinulifera(Vain.) Motyka,U. subscabrosaMotyka andU. yoshihitoiP. Clerc & A. Gerlach sp. nov. (characterized by a lax medulla with non-conglutinated hyphae).Usnea krogianais a new record for Asia;Usnea brasiliensis,Usnea confusaandU. croceorubescensare new records for the Philippines. This is the first phylogenetic study to include DNA sequences ofUsneafrom the Philippines. Molecular data from the ITS rDNA (76 newly generated sequences) are presented for most taxa except forU. himalayana,U. longissimaandU. subscabrosa. At least six further taxa remain unidentified, awaiting the collection of additional specimens. 

Small nanoparticles of ceria deposited on a powder of CuO display a very high selectivity for the production of methanol via CO2 hydrogenation. CeO2/CuO catalysts with ceria loadings of 5%, 20%, and 50% were investigated. Among these, the system with 5% CeOx showed the best catalytic performance at temperatures between 200 and 350 °C. The evolution of this system under reaction conditions was studied using a combination of environmental transmission electron microscopy (E-TEM), in situ X-ray absorption spectroscopy (XAS), and time-resolved X-ray diffraction (TR-XRD). For 5% CeOx/Cu, the in situ studies pointed to a full conversion of CuO into metallic copper, with a complete transformation of Ce4+ into Ce3+. Images from E-TEM showed drastic changes in the morphology of the catalyst when it was exposed to H2, CO2, and CO2/H2 mixtures. Under a CO2/H2 feed, there was a redispersion of the ceria particles that was detected by E-TEM and in situ TR-XRD. These morphological changes were made possible by the inverse oxide/metal configuration and facilitate the binding and selective conversion of CO2 to methanol. 

Polymeric materials have become an integral part of our society, and their high demand has created a large quantity of polymers that end up in the waste stream. For instance, poly(ethylene terephthalate) (PET) is widely used in a broad range of applications, where the chemical recycling of PET is of growing interest. Most methods focus on the complete depolymerization of PET to the monomer, however pushing the equilibrium reaction to the monomer is time- and energy-intensive. We hypothesize that by intercepting intermediates in the depolymerization, telechelic oligomers can be captured that can also be used as reactants to produce value-added goods. To this end, the effect of reaction type, catalyst loading, reaction time, and temperature on the evolution of the product chain structure and yield of the glycolysis depolymerization of PET is studied. For a heterogeneous reaction at lower temperatures (165 °C), the rate of depolymerization is sufficiently slow to offer access to a broad range of molecular weight products (3000–10 000 Daltons) at a high yield (nearly 100%). At higher heterogeneous reaction temperatures (175 and 185 °C), the reaction rate increases, producing oligomers of a narrower molecular weight range (2000–5000 Daltons) with significant loss of the original PET, up to 40%, as water soluble products. In the heterogeneous reaction, little change was observed when altering the catalyst loading at higher temperatures, but lower temperatures and decreased catalyst loading produce accessible higher molecular weight oligomers. Homogeneous catalysis of the glycolysis reactions increases the rate of depolymerization, such that it is difficult to isolate oligomers with M n > 1000 Daltons. The oligomers from heterogeneous reactions were used as reactants to form block copolymers with ethylene glycol, exemplifying their use as precursors in the production of value-added materials. These experiments, therefore, offer crucial insight into how reaction conditions can be readily tuned to produce target telechelic oligomers of PET. 

Fast microfluidic mixers are a valuable tool for studying solution-phase chemical reaction kinetics and molecular processes with spectroscopy. However, microfluidic mixers that are compatible with infrared vibrational spectroscopy have seen only limited development due to the poor infrared transparency of the current microfabrication material. We describe the design, fabrication, and characterization of CaF2-based continuous flow turbulent mixers, which are capable of measuring kinetics in the millisecond time window with infrared spectroscopy, when integrated into an infrared microscope. Kinetics measurements demonstrate the ability to resolve relaxation processes with 1 millisecond time resolution, and straightforward improvements are described that should result in sub-100 µs time-resolution.