DISCOVERY OF RR LYRAE STARS IN THE NUCLEAR BULGE OF THE MILKY WAY

Indexación: Web of ScienceGalactic nuclei, such as that of the Milky Way, are extreme regions with high stellar densities, and in most cases, the hosts of a supermassive black hole. One of the scenarios proposed for the formation of the Galactic nucleus is merging of primordial globular clusters. An implication of this model is that this region should host stars that are characteristically found in old Milky Way globular clusters. RR Lyrae stars are primary distance indicators, well known representatives of old and metal-poor stellar populations, and therefore are regularly found in globular clusters. Here we report the discovery of a dozen RR Lyrae type ab stars in the vicinity of the Galactic center, i.e., in the so-called nuclear stellar bulge of the Milky Way. This discovery provides the first direct observational evidence that the Galactic nuclear stellar bulge contains ancient stars (>10 Gyr old). Based on this we conclude that merging globular clusters likely contributed to the build-up of the high stellar density in the nuclear stellar bulge of the Milky Way.http://iopscience.iop.org/article/10.3847/2041-8205/830/1/L14/meta;jsessionid=2531FBFFF06C9ECBA4852FB9D1F89851.c1.iopscience.cld.iop.or

A review of the current use of commercial wearable technology and smartphone apps with application in monitoring individuals following total hip replacement surgery

The advent of commercially available wearable activity monitors and smartphone apps allows objective digital monitoring of daily activities of patients before and after THR surgery. A wide variety of wearable activity monitors and smartphone apps are being marketed to assist with enhancing physical activity following surgery. A systematic review of commercial wearable tech- nology and smartphone apps was undertaken to assess the evidence supporting their efficacy in assisting rehabilitation and patient monitoring following THR. A search was conducted using the electronic databases including Medline, CINAHL, Cochrane, PsycARTICLES and PubMed of studies from January 2000 to January 2019. Five studies met the eligibility criteria. A review of the studies found very little evidence to support long term efficacy of the technology in enhancing rehabilitation and patient monitoring post THR. Future work is required to establish which commercially available monitoring technology is most valuable to patients, which ones improve clinical outcomes post THR, and what are the best economical models for their deployment

Evaluation of the effect of different wheats and xylanase supplementation on performance, nutrition and energy utilisation in broiler chicks

The aim of this study was to evaluate the performance, nutrient utilisation and energy metabolism of broiler chicks fed 8 different wheat samples, supplemented or not with xylanase. Seven-hundred sixty eight male broilers (1-day-old) were distributed to 16 experimental treatments (6 replicates per treatment). The treatments were in a factorial arrangement with 8 different wheats and 2 levels of xylanase (0 or 16,000 BXU/kg). The predicted apparent metabolisable energy (AME) of the wheat samples ranged from 13.0 to 13.9 MJ/kg and all diets were formulated to contain the same amount of wheat. Body weight gain (BWG) and feed intake (FI) were measured at 21 d, as was jejunal digesta viscosity, and feed conversion ratio (FCR) calculated. On day 24, one representative bird per pen was selected to calculate whole body energetics. At 21 d, 3 chicks per replicate were randomly allocated to metabolism cages for energy and nutrient utilisation determinations, and were continued on the experimental diets until 24-d-old. No interactions were observed for any performance response variables, ileal nutrient utilisation or digesta viscosity. Xylanase improved BWG and reduced FCR and digesta viscosity (P < 0.05). Wheat influenced dry matter (DM) utilisation and xylanase increased ileal digestible energy (P = 0.04). Xylanase also improved (P < 0.05) DM and nitrogen retention. Apparent metabolisable energy and AME corrected for nitrogen (AMEn) were subject to an interaction whereby wheats 2 and 6, which returned the lowest AME and AMEn values, responded to xylanase supplementation and the remainder did not. Net energy for production and the efficiency of energy use for production were not influenced by xylanase, but were affected by wheat (P < 0.05). Despite the significant differences between wheats with regards to their nutrient utilisation and energy metabolism in birds, xylanase removed this variance and resulted in more homogeneous performance

Under-five mortality: spatial-temporal clusters in Ifakara HDSS in South-eastern Tanzania.

BACKGROUND\ud \ud Childhood mortality remains an important subject, particularly in sub-Saharan Africa where levels are still unacceptably high. To achieve the set Millennium Development Goals 4, calls for comprehensive application of the proven cost-effective interventions. Understanding spatial clustering of childhood mortality can provide a guide in targeting the interventions in a more strategic approach to the population where mortality is highest and the interventions are most likely to make an impact.\ud \ud METHODS\ud \ud Annual child mortality rates were calculated for each village, using person-years observed as the denominator. Kulldorff's spatial scan statistic was used for the identification and testing of childhood mortality clusters. All under-five deaths that occurred within a 10-year period from 1997 to 2006 were included in the analysis. Villages were used as units of clusters; all 25 health and demographic surveillance sites (HDSS) villages in the Ifakara health and demographic surveillance area were included.\ud \ud RESULTS\ud \ud Of the 10 years of analysis, statistically significant spatial clustering was identified in only 2 years (1998 and 2001). In 1998, the statistically significant cluster (p < 0.01) was composed of nine villages. A total of 106 childhood deaths were observed against an expected 77.3. The other statistically significant cluster (p < 0.05) identified in 2001 was composed of only one village. In this cluster, 36 childhood deaths were observed compared to 20.3 expected. Purely temporal analysis indicated that the year 2003 was a significant cluster (p < 0.05). Total deaths were 393 and expected were 335.8. Spatial-temporal analysis showed that nine villages were identified as statistically significant clusters (p < 0.05) for the period covering January 1997-December 1998. Total observed deaths in this cluster were 205 while 150.7 were expected.\ud \ud CONCLUSION\ud \ud There is evidence of spatial clustering in childhood mortality within the Ifakara HDSS. Further investigations are needed to explore the source of clustering and identify strategies of reaching the cluster population with the existing effective interventions. However, that should happen alongside delivery of interventions to the broader population

FindFoci: a focus detection algorithm with automated parameter training that closely matches human assignments, reduces human inconsistencies and increases speed of analysis

Accurate and reproducible quantification of the accumulation of proteins into foci in cells is essential for data interpretation and for biological inferences. To improve reproducibility, much emphasis has been placed on the preparation of samples, but less attention has been given to reporting and standardizing the quantification of foci. The current standard to quantitate foci in open-source software is to manually determine a range of parameters based on the outcome of one or a few representative images and then apply the parameter combination to the analysis of a larger dataset. Here, we demonstrate the power and utility of using machine learning to train a new algorithm (FindFoci) to determine optimal parameters. FindFoci closely matches human assignments and allows rapid automated exploration of parameter space. Thus, individuals can train the algorithm to mirror their own assignments and then automate focus counting using the same parameters across a large number of images. Using the training algorithm to match human assignments of foci, we demonstrate that applying an optimal parameter combination from a single image is not broadly applicable to analysis of other images scored by the same experimenter or by other experimenters. Our analysis thus reveals wide variation in human assignment of foci and their quantification. To overcome this, we developed training on multiple images, which reduces the inconsistency of using a single or a few images to set parameters for focus detection. FindFoci is provided as an open-source plugin for ImageJ

Estimating bank default with generalised extreme value regression models

The paper proposes a novel model for the prediction of bank failures, on the basis of both macroeconomic and bank-specific microeconomic factors. As bank failures are rare, in the paper we apply a regression method for binary data based on extreme value theory, which turns out to be more effective than classical logistic regression models, as it better leverages the information in the tail of the default distribution. The application of this model to the occurrence of bank defaults in a highly bank dependent economy (Italy) shows that, while microeconomic factors as well as regulatory capital are significant to explain proper failures, macroeconomic factors are relevant only when failures are defined not only in terms of actual defaults but also in terms of mergers and acquisitions. In terms of predictive accuracy, the model based on extreme value theory outperforms classical logistic regression models

Risk Factors for Primary Clostridium difficile Infection; Results From the Observational Study of Risk Factors for Clostridium difficile Infection in Hospitalized Patients With Infective Diarrhea (ORCHID)

Background: There are inconsistent data on the risk factors for Clostridium difficile infection (CDI) in the literature. Aims: To use two C. difficile infection (CDI) case-control study groups to compare risk factors in hospitalized patients with diarrhea across different countries. Methods: A multi-center group of CDI cases/controls were identified by standardized testing from seven countries from the prior EUropean, multi-center, prospective bi-annual point prevalence study of CLostridium difficile Infection in hospitalized patients with Diarrhea (EUCLID). A second group of CDI cases/controls was identified from a single center in Germany [parallel study site (PSS)]. Data were extracted from the medical notes to assess CDI risk factors. Univariate analyses and multivariate logistic regression models were used to identify and compare risk factors between the two groups. Results: There were 253 and 158 cases and 921 and 584 controls in the PSS and EUCLID groups, respectively. Significant variables from univariate analyses in both groups were age ≥65, number of antibiotics (OR 1.2 for each additional antibiotic) and prior hospital admission (all p < 0.001). Congestive heart failure, diabetes, admission from assisted living or Emergency Department, proton pump inhibitors, and chronic renal disease were significant in PSS (all p < 0.05) but not EUCLID. Dementia and admitted with other bacterial diseases were significant in EUCLID (p < 0.05) but not PSS. Following multivariate analyses, age ≥ 65, number of antibiotics and prior hospital admission were consistently identified as CDI risk factors in each individual group and combined datasets. Conclusion: Our results show that the same CDI risk factors were identified across datasets. These were age ≥ 65 years, antibiotic use and prior hospital admission. Importantly, the odds of developing CDI increases with each extra antibiotic prescribed

Screening for antimicrobial activity of ten medicinal plants used in Colombian folkloric medicine: A possible alternative in the treatment of non-nosocomial infections

BACKGROUND: The antimicrobial activity and Minimal Inhibitory Concentration (MIC) of the extracts of Bidens pilosa L., Bixa orellana L., Cecropia peltata L., Cinchona officinalis L., Gliricidia sepium H.B. & K, Jacaranda mimosifolia D.Don, Justicia secunda Vahl., Piper pulchrum C.DC, P. paniculata L. and Spilanthes americana Hieron were evaluated against five bacteria (Staphylococcus aureus, Streptococcus β hemolític, Bacillus cereus, Pseudomonas aeruginosa, and Escherichia coli), and one yeast (Candida albicans). These plants are used in Colombian folk medicine to treat infections of microbial origin. METHODS: Plants were collected by farmers and traditional healers. The ethanol, hexane and water extracts were obtained by standard methods. The antimicrobial activity was found by using a modified agar well diffusion method. All microorganisms were obtained from the American Type Culture Collection (ATCC). MIC was determined in the plant extracts that showed some efficacy against the tested microorganisms. Gentamycin sulfate (1.0 μg/ml), clindamycin (0.3 μg/ml) and nystatin (1.0 μg/ml) were used as positive controls. RESULTS: The water extracts of Bidens pilosa L., Jacaranda mimosifolia D.Don, and Piper pulchrum C.DC showed a higher activity against Bacillus cereus and Escherichia coli than gentamycin sulfate. Similarly, the ethanol extracts of all species were active against Staphylococcus aureus except for Justicia secunda. Furthermore, Bixa orellana L, Justicia secunda Vahl. and Piper pulchrum C.DC presented the lowest MICs against Escherichia coli (0.8, 0.6 and 0.6 μg/ml, respectively) compared to gentamycin sulfate (0.9 8g/ml). Likewise, Justicia secunda and Piper pulchrum C.DC showed an analogous MIC against Candida albicans (0.5 and 0.6 μg/ml, respectively) compared to nystatin (0.6 μg/ml). Bixa orellana L, exhibited a better MIC against Bacillus cereus (0.2 μg/ml) than gentamycin sulfate (0.5 μg/ml). CONCLUSION: This in vitro study corroborated the antimicrobial activity of the selected plants used in folkloric medicine. All these plants were effective against three or more of the pathogenic microorganisms. However, they were ineffective against Streptococcus β hemolytic and Pseudomonas aeruginosa. Their medicinal use in infections associated with these two species is not recommended. This study also showed that Bixa orellana L, Justicia secunda Vahl. and Piper pulchrum C.DC could be potential sources of new antimicrobial agents

Enhancing lepton flavour violation in the supersymmetric inverse seesaw beyond the dipole contribution

In minimal supersymmetric models the $Z$-penguin usually provides sub-dominant contributions to charged lepton flavour violating observables. In this study, we consider the supersymmetric inverse seesaw in which the non-minimal particle content allows for dominant contributions of the $Z$-penguin to several lepton flavour violating observables. In particular, and due to the low-scale (TeV) seesaw, the penguin contribution to, for instance, \Br(\mu \to 3e) and $\mu-e$ conversion in nuclei, allows to render some of these observables within future sensitivity reach. Moreover, we show that in this framework, the $Z$-penguin exhibits the same non-decoupling behaviour which had previously been identified in flavour violating Higgs decays in the Minimal Supersymmetric Standard Model.Comment: 29 pages, 9 figures, 4 tables; v2: minor corrections, version to appear in JHE