Cytokinesis in many organisms requires a plasma membrane anchored actomyosin ring, whose contraction facilitates cell division. In yeast and fungi, actomyosin ring constriction is also coordinated ...with division septum assembly. How the actomyosin ring interacts with the plasma membrane and the plasma membrane-localized septum synthesizing machinery remains poorly understood. In Schizosaccharomyces pombe, an attractive model organism to study cytokinesis, the β-1,3-glucan synthase Cps1p / Bgs1p, an integral membrane protein, localizes to the plasma membrane overlying the actomyosin ring and is required for primary septum synthesis. Through a high-dosage suppressor screen we identified an essential gene, sbg1+ (suppressor of beta glucan synthase 1), which suppressed the colony formation defect of Bgs1-defective cps1-191 mutant at higher temperatures. Sbg1p, an integral membrane protein, localizes to the cell ends and to the division site. Sbg1p and Bgs1p physically interact and are dependent on each other to localize to the division site. Loss of Sbg1p results in an unstable actomyosin ring that unravels and slides, leading to an inability to deposit a single contiguous division septum and an important reduction of the β-1,3-glucan proportion in the cell wall, coincident with that observed in the cps1-191 mutant. Sbg1p shows genetic and / or physical interaction with Rga7p, Imp2p, Cdc15p, and Pxl1p, proteins known to be required for actomyosin ring integrity and efficient septum synthesis. This study establishes Sbg1p as a key member of a group of proteins that link the plasma membrane, the actomyosin ring, and the division septum assembly machinery in fission yeast.
Background
Motor control issues are common for people with intellectual disabilities (PWID), resulting in difficulties with basic activities of daily living, including eating. Mastication, which is ...crucial for digestion and overall health, is poorly understood in this population. PWID shows frailty similar to older people, highlighting the importance of comparing masticatory motor control with older adults. This study compared the neuromuscular control of the masticatory muscles in middle‐aged, PWID and older adults.
Methods
A cross‐sectional analytical design was used. During the mastication task of a carrot piece (2 cm in diameter and weighing 0.5 g), surface electromyography was used to record muscle activity patterns from the right and left masseter and temporalis muscles. Principal component analysis (PCA) was used to assess neuromuscular control. A z‐score normalisation of the first component's variance from PCA to identify those individuals with altered neuromuscular control. A mixed ANOVA was performed to assess the interaction between principal components, groups and body composition.
Results
Thirty PWIDs (aged 35–55 years), middle‐aged adults and 32 older adults were recruited. PWID and older adults showed decreased neuromuscular control of the masticatory muscles compared to middle‐aged control adults (P < 0.05). PWID had the highest proportion of individuals with altered neuromuscular control of the masticatory muscle (53%) compared to older adults (19%) and middle‐aged adults (0%) (P < 0.05).
Conclusions
Our results indicate that PWID and older adults have reduced neuromuscular control compared to middle‐aged adults. Notably, a significant proportion of the PWID showed altered masticatory muscle control compared to older adults. Further research is needed to explore the potential benefits of masticatory muscle training for PWID.
We analyze the transport of light in the bulk and at the edge of photonic Lieb lattices, whose unique feature is the existence of a flat band representing stationary states in the middle of the band ...structure that can form localized bulk states. We find that transport in bulk Lieb lattices is significantly affected by the particular excitation site within the unit cell, due to overlap with the flat band states. Additionally, we demonstrate the existence of new edge states in anisotropic Lieb lattices. These states arise due to a virtual defect at the lattice edges and are not described by the standard tight-binding model.
•This ESMO Clinical Practice Guideline provides key recommendations and algorithms for managing metastatic breast cancer.•It covers diagnosis, staging, risk assessment, treatment, disease monitoring, ...palliative care and the patient perspective.•ESMO-MCBS and ESCAT scores are given to describe the levels of evidence for treatment choices.•The authors comprise an international expert group, with recommendations based on available evidence and expert opinion.•In clinical practice, all recommendations provided need to be discussed with patients in a shared decision-making approach.
The effect of unidirectional and cross rolling on the corrosion rate, texture, tensile properties and hemolysis of the Mg-0.375Ga and Mg-0.750Ga alloys was evaluated. Pure Mg and as-cast alloys were ...processed by unidirectional and cross rolling at 400°C to obtain a total thickness reduction of 50%. The corrosion rate was measured by the weight loss method in simulated body fluid. Determination of the hemolysis percentage was carried out by direct contact of specimens with diluted blood. After hot rolling, the mechanical properties of the alloys were improved. The cross-rolled Mg-0.750Ga alloy showed the highest grain refinement (55 μm) and the highest ultimate tensile strength (240 MPa), however, lower elongation (13.9%) than the rolled Mg-0.375Ga alloy. While unidirectional rolling creates a strong basal texture, cross rolling weakens considerably this texture. The Ga addition weakens the basal texture. Corrosion rate of the Mg-Ga alloys was significantly reduced (<1 mm/yr) after heat treatment and hot rolling due the homogenization of the microstructure and the presence of gallium as alloying element. The cross-rolled samples showed higher corrosion than the heat-treated and unidirectionally rolled samples. After rolling, alloys showed hemolysis percentages between 7.1 and 9.3%, values lower than those presented by pure magnesium (>22.7%) and as-cast alloys (>24.2%); however, the alloys are still hemolytic (>5%).
Variability in NGC 3201 Giant Stars Cortés, C. C.; Llancaqueo Albornoz, Á.; Villanova, S. ...
The Astronomical journal,
09/2023, Volume:
166, Issue:
3
Journal Article
Peer reviewed
Open access
Abstract
We present the analysis of 510 light curves in
V
and
I
bands of 255 giant stars in the globular cluster NGC 3201. Our aim is to expand the sample of new types of variables reported in a ...previous study. These variables show a short period (
P
V
< 0.6 day) and a low amplitude (
A
(
V
) < 0.06 mag.). We first searched for variability using the generalized Lomb–Scargle and phase dispersion minimization periodograms of the sample, discarding 167 stars as non-variables. We then applied the significance test and reduced the sample to 88 giants, of which we classified 18 as possible variables, 11 as dubious, 41 as non-variables, and 18 as variables. We finally determined the cluster membership of this sample and grouped each star based on their light-curve shape. The discovered variables show periods in the range 0.2440 <
P
V
< 0.5868 days and amplitudes between 0.010 <
A
(
V
) < 0.064 mag. Within the sample of 18 variable stars, we report the discovery of an object with a period
P
V
= 0.3603 ± 0.0012 and amplitude
A
(
V
) = 0.703 ± 0.029 mag that shows a RR Lyrae ab-type light curve. Additionally, we report two RR Lyrae ab and c types with ultralow amplitude.
Background
Alterations in oral health have a negative impact on the quality of life of persons with intellectual disabilities (PwIDs). Chewing is a process that influences and determines optimal oral ...health. However, little is known about how intellectual disability (ID) affects masticatory performance. This study aimed to analyse the differences in masticatory performance between young adults with IDs, young adults without IDs and older adults without IDs.
Methods
A cross‐sectional analytical design was used. The masticatory performance was evaluated with a chewing gum validated instrument. In addition, the labial and tongue strength was assessed with the Iowa Oral Performance Instrument. We compared the masticatory performance between groups using one‐way analysis of covariance. Body mass index, muscle mass, missing teeth, lip strength and tongue strength were included as separate covariates. A multivariate regression analysis was performed to identify which independent variables could explain masticatory performance in each group.
Results
Thirty‐two PwIDs, 31 young adults without IDs and 32 older adults without IDs were recruited. PwIDs showed poorer masticatory performance compared with older adults (mean difference: −3.06, 95% confidence interval: −3.87 to −2.26) and healthy controls (mean difference: −2.38, 95% confidence interval: −3.19 to −1.57). The analysis of covariance showed significant difference between groups in the masticatory performance (F = 47.35, P < 0.001, ηp2 = 0.507). Missing teeth (P < 0.001), right lip strength (P = 0.025) and tongue strength (P = 0.007) as covariables showed a significant interaction with the model. In the PwID group, lip strength and lack of teeth explained 58% of the variance in masticatory performance (R2 = 0.580, standard error = 1.12, P < 0.001).
Conclusions
Persons with intellectual disabilities have a poorer masticatory performance than adults without IDs. Our findings indicate that the primary determinants of optimal masticatory function in PwIDs are the strength of the lip seal and the number of missing teeth.
Intestinal microbiota changes are associated with the development of obesity. However, studies in humans have generated conflicting results due to high inter-individual heterogeneity in terms of ...diet, age, and hormonal factors, and the largely unexplored influence of gender. In this work, we aimed to identify differential gut microbiota signatures associated with obesity, as a function of gender and changes in body mass index (BMI). Differences in the bacterial community structure were analyzed by 16S sequencing in 39 men and 36 post-menopausal women, who had similar dietary background, matched by age and stratified according to the BMI. We observed that the abundance of the Bacteroides genus was lower in men than in women (P<0.001, Q = 0.002) when BMI was > 33. In fact, the abundance of this genus decreased in men with an increase in BMI (P<0.001, Q<0.001). However, in women, it remained unchanged within the different ranges of BMI. We observed a higher presence of Veillonella (84.6% vs. 47.2%; X2 test P = 0.001, Q = 0.019) and Methanobrevibacter genera (84.6% vs. 47.2%; X2 test P = 0.002, Q = 0.026) in fecal samples in men compared to women. We also observed that the abundance of Bilophila was lower in men compared to women regardless of BMI (P = 0.002, Q = 0.041). Additionally, after correcting for age and sex, 66 bacterial taxa at the genus level were found to be associated with BMI and plasma lipids. Microbiota explained at P = 0.001, 31.17% variation in BMI, 29.04% in triglycerides, 33.70% in high-density lipoproteins, 46.86% in low-density lipoproteins, and 28.55% in total cholesterol. Our results suggest that gut microbiota may differ between men and women, and that these differences may be influenced by the grade of obesity. The divergence in gut microbiota observed between men and women might have a dominant role in the definition of gender differences in the prevalence of metabolic and intestinal inflammatory diseases.
Abstract
In this paper we study stellar variability in the globular cluster NGC 3201 in the magnitude range
V
= 16–17, corresponding to the subgiant branch and blue stragglers region of the cluster. ...Our aim is to expand the sample of new type of variables with low amplitude and a short period found in previous papers. We used observations obtained at the Complejo Astronómico El Leoncito. We applied statistical tests and analyzed periodograms obtained by generalized Lomb–Scargle and phase dispersion minimization methods. We found five stars considered as variables and one as a possible variable. According to their periods (fluctuating between 0.33 and 0.57 days), amplitudes (between 0.03 and 0.87
V
magnitudes), the position in the color–magnitude diagram, and the shape of their phased light curves, they do not resemble any known variable star. Because stellar variability could be produced by more than one process, we propose to complement this work with a spectroscopic analysis to confirm our results.
Abstract
We present the light-curve period analysis of 36 Beta Lyrae stars from the OMC Archive. We check the reference period of the sample by applying the phase dispersion minimization periodogram. ...From our research, we determine the orbital period of five stars in the sample. One of them is CP Psc, showing a prominent hump in the light curve before the deeper eclipse, and revealing a period of 0.6847936 day. Additionally, we improved the previously published orbital period for 27 stars. Within this sample, we discovered three stars with the O’Connell effect, and we identified a system with a second period known as II Per, with an orbital period of 0.4798512 day and a long period 9.2724776 days. The light curve of V 747 Cen can be reproduced with a dark spot of temperature about 70% its surroundings, which covers one of the poles of the more massive star.
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