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Weighted shift operators, orthogonal polynomials and chain sequences.
No full textThe main purpose of this paper is to use chain sequences to study spectral properties of weighted shift operators A and of tridiagonal operators ReA. Characterizations of chain sequences and relations to Haar sequences are derived. We use these results to compare the spectral radius, the numerical radius and the norm of A and ReA. As an example we study orthogonal polynomials defined by a recursion formula with almost constant coefficients
Powers of the Dirichlet kernel with respect to orthogonal polynomials and related operators.
No full textLet { P n } ∞ n =0 be an orthogonal polynomial sequence on the real line with respect to a probability measure μ with compact and infinite support and D N = ∑ N n =0 P n h n the N th element of the Dirichlet kernel, where h n = ( ∫ P 2 n dμ ) − 1 . We are investigating the r th integer power D r N and prove for special orthogonal polynomials that in the case r ∈ N { 1 } the sequence { D r N } ∞ N =0 gives rise to an approximate identity. This applies for example for Jacobi polynomials
Genetic heterogeneity and subtypes of major depression.
No full textMajor depression (MD) is a heterogeneous disorder; however, the extent to which genetic factors distinguish MD patient subgroups (genetic heterogeneity) remains uncertain. This study sought evidence for genetic heterogeneity in MD. Using UK Biobank cohort, the authors defined 16 MD subtypes within eight comparison groups (vegetative symptoms, symptom severity, comorbid anxiety disorder, age at onset, recurrence, suicidality, impairment, and postpartum depression; N ~ 3000-47000). To compare genetic component of these subtypes, subtype-specific genome-wide association studies were performed to estimate SNP-heritability, and genetic correlations within subtype comparison and with other related disorders/traits. The findings indicated that MD subtypes were divergent in their SNP-heritability, and genetic correlations both within subtype comparisons and with other related disorders/traits. Three subtype comparisons (vegetative symptoms, age at onset, and impairment) showed significant differences in SNP-heritability; while genetic correlations within subtype comparisons ranged from 0.55 to 0.86, suggesting genetic profiles are only partially shared among MD subtypes. Furthermore, subtypes that are more clinically challenging, e.g., early-onset, recurrent, suicidal, more severely impaired, had stronger genetic correlations with other psychiatric disorders. MD with atypical-like features showed a positive genetic correlation (+0.40) with BMI while a negative correlation (-0.09) was found in those without atypical-like features. Novel genomic loci with subtype-specific effects were identified. These results provide the most comprehensive evidence to date for genetic heterogeneity within MD, and suggest that the phenotypic complexity of MD can be effectively reduced by studying the subtypes which share partially distinct etiologies
Reduced metabolic efficiency in sedentary eucaloric conditions predicts greater weight regain in adults with obesity following sustained weight loss.
No full textBACKGROUND: Successful long-term weight loss maintenance after caloric restriction (CR) is rarely achieved. Besides known metabolic, behavioural, and cognitive factors, 24-hour energy expenditure (24hEE) relative to body size (i.e., metabolic efficiency) might influence subsequent weight loss maintenance. METHODS: Eleven participants with obesity (BMI = 39.0 ± 8.7 kg/m2, body fat = 36.1 ± 6.4%) had 24hEE measured in a whole-room indirect calorimeter during eucaloric conditions and weight stability prior to starting a 6-week inpatient CR study (50% of daily energy needs). Twenty-four-hour energy expenditure was adjusted via regression analysis for fat free mass (FFM) and fat mass (FM) by DXA. Body composition was reassessed at the end of CR and after 1-year follow-up. Free-living weight was assessed by monthly weight measurements during 12 months. RESULTS: After 6-week CR, participants lost 8.5 ± 2.7% weight (FFM: -6.3 ± 3.6 kg, FM: -3.4 ± 1.2 kg) but regained 5.1 ± 8.0% 1 year following CR, which was mostly due to FFM regain (+5.7 ± 5.5 kg) and unchanged FM. A relatively higher 24hEE by 100 kcal/day prior to CR was associated with an average greater rate of weight regain by +0.3 kg/month during follow-up and a greater final weight regain by +5.1 kg after 1 year of follow-up. CONCLUSION: These results suggest that reduced metabolic efficiency in 24hEE during eucaloric, sedentary conditions may predict greater weight regain after CR-induced weight loss
Longitudinal association of built environment pattern with DXA-derived body fat in elderly Hong Kong Chinese: A latent profile analysis.
No full textBACKGROUND: One major limitation of prior studies regarding the associations between built environment (BE) and obesity has been the use of anthropometric indices (e.g., body mass index [BMI]) for assessing obesity status, and there has been limited evidence of associations between BE and body fat. This study aimed to explore the longitudinal association between BE and body fat in a cohort of elderly Hong Kong Chinese and examine whether the BE-body fat associations differed by BMI categories. METHODS: Between 2001 and 2003, 3944 participants aged 65-98 years were recruited and followed for a mean of 6.4 years. BE characteristics were assessed via Geographic Information System. Body fat (%) at whole body and regional areas (trunk, limbs, android, and gynoid) were assessed by dual energy X-ray absorptiometry at baseline and three follow-ups. Latent profile analysis was used to derive BE class, and linear mixed-effects models were used to investigate the associations of BE class with changes in body fat. Stratified analyses by BMI categories were also conducted. RESULTS: Three BE classes were identified. Participants in Class 2 (characterized by greater open space and proportion of residential land use) had a slower increase in whole body fat (B = -0.403, 95% confidence interval [CI]: -0.780, -0.014) and limbs fat (-0.471, 95% CI: -0.870, -0.071) compared with participants in Class 1 (characterized by high proportion of commercial land use). There were significant interactions of BE class with BMI, and participants in Class 2 had a slower increase in whole body fat and regional fat compared with participants in Class 1 (B ranging from -0.987 [limbs] to -0.523 [gynoid]) among overweight and obese participants only. CONCLUSIONS: We found that those who resided in the areas characterized by greater open space and proportion of residential land use had a slower body fat increase
Not just passengers, but co-pilots! Non-rhizobial nodule-associated bacteria promote cowpea growth and symbiosis with (brady)rhizobia.
No full textAIMS: To isolate and characterize non-rhizobial nodule-associated bacteria (NAB) from cowpea root-nodules regarding their performance of plant-growth-promoting mechanisms and their ability to enhance cowpea growth and symbiosis when co-inoculated with bradyrhizobia. METHODS AND RESULTS: Sixteen NAB were isolated, identified, and in vitro evaluated for plant growth promotion traits. The ability to promote cowpea growth was analyzed when co-inoculated with Bradyrhizobium pachyrhizi BR 3262 in sterile and non-sterile substrates. The 16S rRNA gene sequences analysis revealed that NAB belonged to the genera Chryseobacterium (4), Bacillus (3), Microbacterium (3), Agrobacterium (1), Escherichia (1), Delftia (1), Pelomonas (1), Sphingomonas (1), and Staphylococcus (1). All strains produced different amounts of auxin siderophores and formed biofilms. Twelve out of the 16 strains carried the nifH, a gene associated with nitrogen fixation. Co-inoculation of NAB (ESA 424 and ESA 29) with Bradyrhizobium pachyrhizi BR 3262 significantly promoted cowpea growth, especially after simultaneous inoculation with the three strains. CONCLUSIONS: NAB are efficient cowpea growth promoters and can improve the efficiency of the symbiosis between cowpea and the N2-fixing microsymbiont B. pachyrhizi BR 3262, mainly under a specific triple microbial association
TET1 promotes growth of T-cell acute lymphoblastic leukemia and can be antagonized via PARP inhibition.
No full textT-cell acute lymphoblastic leukemia (T-ALL) is an aggressive hematological cancer characterized by skewed epigenetic patterns, raising the possibility of therapeutically targeting epigenetic factors in this disease. Here we report that among different cancer types, epigenetic factor TET1 is highly expressed in T-ALL and is crucial for human T-ALL cell growth in vivo. Knockout of TET1 in mice and knockdown in human T cell did not perturb normal T-cell proliferation, indicating that TET1 expression is dispensable for normal T-cell growth. The promotion of leukemic growth by TET1 was dependent on its catalytic property to maintain global 5-hydroxymethylcytosine (5hmC) marks, thereby regulate cell cycle, DNA repair genes, and T-ALL associated oncogenes. Furthermore, overexpression of the Tet1-catalytic domain was sufficient to augment global 5hmC levels and leukemic growth of T-ALL cells in vivo. We demonstrate that PARP enzymes, which are highly expressed in T-ALL patients, participate in establishing H3K4me3 marks at the TET1 promoter and that PARP1 interacts with the TET1 protein. Importantly, the growth related role of TET1 in T-ALL could be antagonized by the clinically approved PARP inhibitor Olaparib, which abrogated TET1 expression, induced loss of 5hmC marks, and antagonized leukemic growth of T-ALL cells, opening a therapeutic avenue for this disease
Bernstein inequality in L<sup>α</sup> norms.
No full textThe classical Bernstein inequality estimates the derivative of a polynomial at a fixed point with the supremum norm and a factor depending on the point only. Recently, this classical inequality was generalized to arbitrary compact subsets on the real line. That generalization is sharp and naturally introduces potential theoretical quantities. It also gives a hint how a sharp L α Bernstein inequality should look like. In this paper we prove this conjectured Lα Bernstein type inequality and we also prove its sharpness
Radiochirurgie vs. Ganzhirnbestrahlung– mehr Lebensqualität, mehr Leistungsfähigkeit?
No full textHintergrund: Lebensqualität und Neurokognition rückt zunehmend in den klinischen
und wissenschaftlichen Fokus in der Behandlung von Hirnmetastasen.
Ziel: Die vorliegende Arbeit basiert auf einer selektiven Literaturrecherche in der
Datenbank PubMed zum Thema neurokognitive Veränderungen und Lebensqualität
nach zerebraler Radiotherapie. Es wird eine Übersicht über die aktuelle Datenlage
gegeben.
Ergebnisse und Schlussfolgerung: Die technischen Verbesserungen in der
Radioonkologie führen zu schneller und effektiver Hochpräzisionsbestrahlung. Die
potenziell geringere intrakranielle Kontrolle nach stereotaktischer Radiochirurgie
(„stereotactic radiosurgery“, SRS) scheint im Vergleich zur Ganzhirnbestrahlung („whole
brain radiation therapy“, WBRT) keinen relevanten Einfluss auf das Überleben zu haben.
Daher ist die Erhaltung der Neurokognition und der Lebensqualität zentrales Ziel der
Behandlung und Gegenstand der aktuellen Forschung
Investigation of COVID-19-related lockdowns on the air pollution changes in augsburg in 2020, Germany.
No full textThe COVID-19 pandemic in Germany in 2020 brought many regulations to impede its transmission such as lockdown. Hence, in this study, we compared the annual air pollutants (CO, NO, NO2, O3, PM10, PM2.5, and BC) in Augsburg in 2020 to the record data in 2010–2019. The annual air pollutants in 2020 were significantly (p < 0.001) lower than that in 2010–2019 except O3, which was significantly (p = 0.02) higher than that in 2010–2019. In a depth perspective, we explored how lockdown impacted air pollutants in Augsburg. We simulated air pollutants based on the meteorological data, traffic density, and weekday and weekend/holiday by using four different models (i.e. Random Forest, K-nearest Neighbors, Linear Regression, and Lasso Regression). According to the best fitting effects, Random Forest was used to predict air pollutants during two lockdown periods (16/03/2020–19/04/2020, 1st lockdown and 02/11/2020–31/12/2020, 2nd lockdown) to explore how lockdown measures impacted air pollutants. Compared to the predicted values, the measured CO, NO2, and BC significantly reduced 18.21%, 21.75%, and 48.92% in the 1st lockdown as well as 7.67%, 32.28%, and 79.08% in the 2nd lockdown. It could be owing to the reduction of traffic and industrial activities. O3 significantly increased 15.62% in the 1st lockdown but decreased 40.39% in the 2nd lockdown, which may have relations with the fluctuations the NO titration effect and photochemistry effect. PM10 and PM2.5 were significantly increased 18.23% an 10.06% in the 1st lockdown but reduced 34.37% and 30.62% in the 2nd lockdown, which could be owing to their complex generation mechanisms