Nomenclatural notes on some species of Arthothelium (Lichenized Ascomycotina)

Nomenclatural changes are presented for eleven species of the genus Arthothelium, resulting in four new combinations and five new synonyms. The new combinations are: Arthothelium subbessale (Nyl.) comb. nov., Cyclographina circumscissa (Vain.) comb. nov., Minksia angolensis (Nyl.) comb. nov. and Thelotrema puniceum (Müll. Arg.) comb. nov. In addition, a new species is described, Arthothelium endoaurantiacum

Application of Fourier Transform Infrared Spectroscopy (FTIR) for assessing biogenic silica sample purity in geochemical analyses and palaeoenvironmental research

The development of a rapid and non-destructive method to assess purity levels in samples of biogenic silica prior to geochemical/isotope analysis remains a key objective in improving both the quality and use of such data in environmental and palaeoclimatic research. Here a Fourier Transform Infrared Spectroscopy (FTIR) mass-balance method is demonstrated for calculating levels of contamination in cleaned sediment core diatom samples from Lake Baikal, Russia. Following the selection of end-members representative of diatoms and contaminants in the analysed samples, a mass-balance model is generated to simulate the expected FTIR spectra for a given level of contamination. By fitting the sample FTIR spectra to the modelled FTIR spectra and calculating the residual spectra, the optimum best-fit model and level of contamination is obtained. When compared to X-ray Fluorescence (XRF) the FTIR method portrays the main changes in sample contamination through the core sequence, permitting its use in instances where other, destructive, techniques are not appropriate. The ability to analyse samples of <1 mg enables, for the first time, routine analyses of small sized samples. Discrepancies between FTIR and XRF measurements can be attributed to FTIR end-members not fully representing all contaminants and problems in using XRF to detect organic matter external to the diatom frustule. By analysing samples with both FTIR and XRF, these limitations can be eliminated to accurately identify contaminated samples. Future, routine use of these techniques in palaeoenvironmental research will therefore significantly reduce the number of erroneous measurements and so improve the accuracy of biogenic silica/diatom based climate reconstructions

Picosecond ionization dynamics in femtosecond filaments at high pressures

We investigate the plasma dynamics inside a femtosecond-pulse-induced filament generated in an argon gas for a wide range of pressures up to 60 bar. At higher pressures, we observe ionization immediately following a pulse, with up to a threefold increase in the electron density within 30 ps after the filamentary propagation of a femtosecond pulse. Our study suggests that this picosecond evolution can be attributed to collisional ionization including Penning and associative ionizations and electron-impact ionization of excited atoms generated during the pulse. The dominance of excited atoms over ionized atoms at the end of the pulse also indicates an intrapulse inhibition of avalanche ionization. This delayed ionization dynamics provides evidence for diagnosing atomic and molecular excitation and ionization in intense laser interaction with high-pressure gases

Mechanistic understanding of pore evolution enables high performance mesoporous silicon production for lithium-ion batteries

The cycling of silicon anodes within a lithium-ion battery (LIB) leads to degradation and capacity fade due to the 280% volume change of silicon. Many avenues of silicon synthesis have been explored to produce nanostructures which can withstand this change in volume. Magnesiothermic Reduction (MgTR) shows significant promise over other syntheses in scalability, economic and environmental aspects for producing porous silicon nanostructures. The problem with MgTR is a lack of understanding regarding the pore evolution of porous silicon based on reduction parameters and precursor material, which in turn limits predictive design for desired applications. Here we show that the pore structure of porous silicon is strongly related to the interconnectivity of silicon crystallites. We show that the MgTR is a thermodynamically driven equilibria which determines the purity of the silicon product. Higher temperatures also cause sintering of silicon nanocrystallites. We show that it is the interconnectivity of these crystallites that determine the pore size and distribution within porous silicon. These findings apply to a wide variety of porous silica precursors and we show this mechanism is true for the introduction of pores into nonporous quartz after MgTR. Further, we show that by exploiting this mechanism, mesoporous silicon can be produced which has excellent promise for LIB applications with a capacity of 2170 mAh/g after 100 cycles. The findings herein can be taken forward to design optimal materials for LIB applications. These results strongly support the potential for reduction in silicon costs for LIB in both economic and environmental terms as well as for a reverse engineering approach to design specific porous silicon for desired applications even beyond LIB

Amount of health care and self-care following a randomized clinical trial comparing flexion-distraction with exercise program for chronic low back pain

BACKGROUND: Previous clinical trials have assessed the percentage of participants who utilized further health care after a period of conservative care for low back pain, however no chiropractic clinical trial has determined the total amount of care during this time and any differences based on assigned treatment group. The objective of this clinical trial follow-up was to assess if there was a difference in the total number of office visits for low back pain over one year after a four week clinical trial of either a form of physical therapy (Exercise Program) or a form of chiropractic care (Flexion Distraction) for chronic low back pain. METHODS: In this randomized clinical trial follow up study, 195 participants were followed for one year after a four-week period of either a form of chiropractic care (FD) or a form of physical therapy (EP). Weekly structured telephone interview questions regarded visitation of various health care practitioners and the practice of self-care for low back pain. RESULTS: Participants in the physical therapy group demonstrated on average significantly more visits to any health care provider and to a general practitioner during the year after trial care (p < 0.05). No group differences were noted in the number of visits to a chiropractor or physical therapist. Self-care was initiated by nearly every participant in both groups. CONCLUSION: During a one-year follow-up, participants previously randomized to physical therapy attended significantly more health care visits than those participants who received chiropractic care

Prevalence of infections among 6-16 years old children attending a semi-rural school in Western Maharashtra, India

Background: Infections are an important cause of morbidity in rural India. Reports on the prevalence of infections in older childrenand their effects on growth are scarce. Objective: The objectives were to determine the prevalence of common infections among6-16 year old school-children in a semi-rural setting in Western India and to assess the influence of infections on the growth status ofthe children. Materials and Methods: This cross-sectional study was conducted in a semi-rural setting in a Zilla Parishad PrimarySchool, Karegaon, Maharashtra. 802 children (boys = 439), 6-16 years of age were assessed. Data on height, weight and infectionrelatedsymptoms reported by children (pre-tested, validated questionnaire) were collected. K-means cluster analysis was used to createthree clusters based on the severity of infections, and one-way analysis of variance with post-hoc Tukey’s multiple comparisons wasused to test the significance of differences in means of various characteristics of the subjects in three clusters. Results: 43% boys and49% girls reported symptoms of respiratory tract infections occasionally, and 28% boys and 27% girls complained of gastrointestinal(GI) infections occasionally. Children with more severe infections were more likely to be shorter and lighter; this was more marked ingirls. Conclusions: Rural school-going children (aged 6-16 years) suffer from high rates of infections, mainly upper respiratory tractinfections followed by GI tract infections

Learning Joint Spatial-Temporal Transformations for Video Inpainting

High-quality video inpainting that completes missing regions in video frames is a promising yet challenging task. State-of-the-art approaches adopt attention models to complete a frame by searching missing contents from reference frames, and further complete whole videos frame by frame. However, these approaches can suffer from inconsistent attention results along spatial and temporal dimensions, which often leads to blurriness and temporal artifacts in videos. In this paper, we propose to learn a joint Spatial-Temporal Transformer Network (STTN) for video inpainting. Specifically, we simultaneously fill missing regions in all input frames by self-attention, and propose to optimize STTN by a spatial-temporal adversarial loss. To show the superiority of the proposed model, we conduct both quantitative and qualitative evaluations by using standard stationary masks and more realistic moving object masks. Demo videos are available at https://github.com/researchmm/STTN.Comment: Accepted by ECCV202