2,852 research outputs found
Atmospheric Parameters and Metallicities for 2191 stars in the Globular Cluster M4
We report new metallicities for stars of Galactic globular cluster M4 using
the largest number of stars ever observed at high spectral resolution in any
cluster. We analyzed 7250 spectra for 2771 cluster stars gathered with the VLT
FLAMES+GIRAFFE spectrograph at VLT. These medium resolution spectra cover by a
small wavelength range, and often have very low signal-to-noise ratios. We
attacked this dataset by reconsidering the whole method of abundance analysis
of large stellar samples from beginning to end. We developed a new algorithm
that automatically determines the atmospheric parameters of a star. Nearly all
data preparation steps for spectroscopic analyses are processed on the
syntheses, not the observed spectra. For 322 Red Giant Branch stars with we obtain a nearly constant metallicity, ( = 0.02). No difference in the metallicity at the level of
is observed between the two RGB sequences identified by
\cite{Monelli:2013us}. For 1869 Subgiant and Main Sequence Stars we
obtain ( = 0.09) after fixing the
microturbulent velocity. These values are consistent with previous studies that
have performed detailed analyses of brighter RGB stars at higher spectroscopic
resolution and wavelength coverage. It is not clear if the small mean
metallicity difference between brighter and fainter M4 members is real or is
the result of the low signal-to-noise characteristics of the fainter stars. The
strength of our approach is shown by recovering a metallicity close to a single
value for more than two thousand stars, using a dataset that is non-optimal for
atmospheric analyses. This technique is particularly suitable for noisy data
taken in difficult observing conditions.Comment: 17 pages, 20 figures, 3 tables. Accepted for publication in The
Astronomical Journa
Bosentan in the treatment of pulmonary arterial hypertension with the focus on the mildly symptomatic patient
Pulmonary arterial hypertension (PAH) is a progressive disease with poor survival outcomes. Bosentan is an oral endothelin-1 receptor antagonist (ERA) that has been shown in a large randomized placebo-controlled trial (BREATHE-1) to be effective at improving exercise tolerance in patients with PAH in functional class III and IV. Further studies have been conducted showing: benefit in smaller subgroups of PAH, eg, congenital heart disease, efficacy in combination with other PAH therapies, eg, sildenafil, improved long-term survival compared with historical controls. More recently, controlled trials of new ERAs have included patients with milder symptoms; those in functional class II. Analysis of the functional class II data is often limited by small numbers. These trials have generally shown a similar treatment effect to bosentan, but there are no controlled trials directly comparing these new ERAs. The EARLY trial exclusively enrolled functional class II patients and assessed hemodynamics at 6 months. Though significant, the reduction in pulmonary vascular resistance is merely a surrogate marker for the intended aim of delaying disease progression. Significant adverse effects associated with bosentan include edema, anemia and transaminase elevation. These may preclude a long duration of treatment. Further studies are required to determine optimum treatment strategy in mild disease
Hubungan Indeks Massa Tubuh dengan Kejadian Kanker Prostat dan Gleason Score di Rumah Sakit Siloam Kupang
Prostate cancer can be termed as the most commonly diagnosed cancer in men. The risk of prostate cancer increases with age. Knowing whether there is a relationship between Body Mass Index (BMI) with prostate cancer and gleason score at Siloam Hospital Kupang. Methods, qualitative research method with cross sectional design and using secondary data from medical records with consecutive sampling technique. Results, patients diagnosed with prostate cancer at Siloam Hospital for the 2017-2021 period were 80 cases and 60 cases were not prostate cancer. The BMI in the group of prostate cancer patients was 54 people (67.5%) in the non-obese group and 34 people (56.67%) in non-prostate cancer. The most cases of prostate cancer with histopathological degrees of High Gleason Score were 45 cases (56.25%), and histopathological degrees of Low Grade Score were 35 cases (43.75). The chi square analysis, it is known that there is no relationship between BMI and the incidence of prostate cancer having a p value = 0.189 (p > 0.05) and the Gleason Score has a p value = 0.764 (p > 0.05). Conclusion there was no relationship between BMI and the incidence of prostate cancer and gleason score at Siloam Hospital Kupang.Kanker prostat dapat disebut sebagai kanker yang umum didiagnosis pada pria. Risiko kanker prostat meningkat seiring bertambahnya usia. Tujuan penelitian ini untuk mengetahui apakah adanya hubungan antara Indeks Massa Tubuh (IMT) dengan kanker prostat dan gleason score di Rumah Sakit Siloam Kupang. Metode penelitian kualitatif dengan desain cross sectional dan menggunakan data sekunder rekam medik dengan teknik consecutive sampling. Hasil penelitian, Pasien dengan diagnosa kanker prostat di Rumah Sakit Siloam Kupang periode 2017-2021 sebanyak 80 kasus dan bukan kanker prostat sebanyak 60 kasus. Indeks Massa Tubuh pada kelompok pasien kanker prostat terbanyak pada non obesitas sebanyak 54 orang (67,5%) dan pada bukan kanker prostat sebanyak 34 orang (56,67%). Kasus kanker prostat terbanyak dengan derajat histopatologi High Gleason Score sebanyak 45 kasus (56,25%), dan derajat histopatologi Low Grade Score sebanyak 35 kasus (43,75). Berdasarkan hasil analisis dengan chi square, diketahui bahwa tidak ada hubungan antara Indeks Massa Tubuh dengan Kejadian Kanker Prostat memiliki nilai p = 0,189 (p > 0,05) dan dengan Gleason Score memiliki nilai p = 0,764 (p > 0,05) Simpulan, Tidak terdapat hubungan antara Indeks Massa Tubuh dengan kejadian kanker prostat dan gleason score di Rumah Sakit Siloam Kupang
Including older fish in fisheries management: A new age-based indicator and reference point for exploited fish stocks
Larger and older fish contribute disproportionately to spawning and play an important role in the replenishment of exploited stocks. Fishing often removes specific size- and age-classes, with direct impacts on stock productivity and population resilience. Despite this, fisheries advice is commonly based on estimates of spawning stock biomass (SSB) and fishing mortality (F) and makes little reference to the importance of size and/or age structure. Consequently, there is a need for indicators of size and/or age structure to better inform fisheries management and help assess global sustainability goals. Here, we introduce a new age-based indicator ABI(MSY) that monitors age structure relative to the equilibrium age structure at F-MSY. We apply this new indicator to 72 commercially important stocks in the Northeast Atlantic, covering 26 species, which collectively contributed 86% of all commercial catches in the region in 2019. We estimate that 62% (45 stocks) currently have proportionally fewer older fish relative to F-MSY conditions, whereas 38% (27 stocks) have proportionally more older fish; we also note patterns with respect to geographic area and taxonomic family. Simulation testing demonstrated that ABI(MSY) is responsive to overfishing and generally tracks (with high sensitivity and specificity) a common measure of stock depletion, SSB relative to B-MSY. Throughout, we show that ABI(MSY) provides information on the age structure of exploited stocks that is complementary to conventional reference points for SSB and F. Further, the framework used to estimate ABI(MSY )make it well placed for integration into current advisory frameworks on fisheries management
Are task representations gated in macaque prefrontal cortex?
A recent paper (Flesch et al, 2022) describes behavioural and neural data
suggesting that task representations are gated in the prefrontal cortex in both
humans and macaques. This short note proposes an alternative explanation for
the reported results from the macaque data
The SOD2 C47T polymorphism influences NAFLD fibrosis severity: evidence from case-control and intra-familial allele association studies.
AIMS:
Non-alcoholic fatty liver disease (NAFLD) is a complex disease trait where genetic variations and environment interact to determine disease progression. The association of PNPLA3 with advanced disease has been consistently demonstrated but many other modifier genes remain unidentified. In NAFLD, increased fatty acid oxidation produces high levels of reactive oxygen species. Manganese-dependent superoxide dismutase (MnSOD), encoded by the SOD2 gene, plays an important role in protecting cells from oxidative stress. A common non-synonymous polymorphism in SOD2 (C47T; rs4880) is associated with decreased MnSOD mitochondrial targeting and activity making it a good candidate modifier of NAFLD severity.
METHODS:
The relevance of the SOD2 C47T polymorphism to fibrotic NAFLD was assessed by two complementary approaches: we sought preferential transmission of alleles from parents to affected children in 71 family trios and adopted a case-control approach to compare genotype frequencies in a cohort of 502 European NAFLD patients.
RESULTS:
In the family study, 55 families were informative. The T allele was transmitted on 47/76 (62%) possible occasions whereas the C allele was transmitted on only 29/76 (38%) occasions, p=0.038. In the case control study, the presence of advanced fibrosis (stage>1) increased with the number of T alleles, p=0.008 for trend. Multivariate analysis showed susceptibility to advanced fibrotic disease was determined by SOD2 genotype (OR 1.56 (95% CI 1.09-2.25), p=0.014), PNPLA3 genotype (p=0.041), type 2 diabetes mellitus (p=0.009) and histological severity of NASH (p=2.0×10(-16)).
CONCLUSIONS:
Carriage of the SOD2 C47T polymorphism is associated with more advanced fibrosis in NASH
Climate Change Impacts on Microbiota in Beach Sand and Water : Looking Ahead
Beach sand and water have both shown relevance for human health and their microbiology have been the subjects of study for decades. Recently, the World Health Organization recommended that recreational beach sands be added to the matrices monitored for enterococci and Fungi. Global climate change is affecting beach microbial contamination, via changes to conditions like water temperature, sea level, precipitation, and waves. In addition, the world is changing, and humans travel and relocate, often carrying endemic allochthonous microbiota. Coastal areas are amongst the most frequent relocation choices, especially in regions where desertification is taking place. A warmer future will likely require looking beyond the use of traditional water quality indicators to protect human health, in order to guarantee that waterways are safe to use for bathing and recreation. Finally, since sand is a complex matrix, an alternative set of microbial standards is necessary to guarantee that the health of beach users is protected from both sand and water contaminants. We need to plan for the future safer use of beaches by adapting regulations to a climate-changing world.Peer reviewe
Chimeric streptavidins as host proteins for artificial metalloenzymes
The
streptavidin scaffold was expanded with well-structured naturally
occurring motifs. These chimeric scaffolds were tested as hosts for
biotinylated catalysts as artificial metalloenzymes (ArM) for asymmetric
transfer hydrogenation, ring-closing metathesis and anion−π
catalysis. The additional second coordination sphere elements significantly
influence both the activity and the selectivity of the resulting hybrid
catalysts. These findings lead to the identification of propitious
chimeric streptavidins for future directed evolution efforts of artificial
metalloenzymes
The Discrete Representation of Continuously Moving Indeterminate Objects
AbstractTo incorporate indeterminacy in spatio-temporal database systems, grey modeling method is used for the calculations of the discrete models of indeterminate two dimension continuously moving objects. The Grey Model GM (1, 1) model generated from the snapshot sequence reduces the randomness of discrete snapshot and generates the holistic measure of object's movements. Comparisons to traditional linear models show that when information is limited this model can be used in the interpolation and near future prediction of uncertain continuously moving spatio-temporal objects
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