576 research outputs found
Selfâconsistent molecular orbital methods. XXIII. A polarizationâtype basis set for secondârow elements
The 6â31G* and 6â31G** basis sets previously introduced for firstârow atoms have been extended through the secondârow of the periodic table. Equilibrium geometries for oneâheavyâatom hydrides calculated for the twoâbasis sets and using HartreeâFock wave functions are in good agreement both with each other and with the experimental data. HF/6â31G* structures, obtained for twoâheavyâatom hydrides and for a variety of hypervalent secondârow molecules, are also in excellent accord with experimental equilibrium geometries. No large deviations between calculated and experimental single bond lengths have been noted, in contrast to previous work on analogous firstârow compounds, where limiting HartreeâFock distances were in error by up to a tenth of an angstrom. Equilibrium geometries calculated at the HF/6â31G level are consistently in better agreement with the experimental data than are those previously obtained using the simple splitâvalance 3â21G basis set for both normalâ and hypervalent compounds. Normalâmode vibrational frequencies derived from 6â31G* level calculations are consistently larger than the corresponding experimental values, typically by 10%â15%; they are of much more uniform quality than those obtained from the 3â21G basis set. Hydrogenation energies calculated for normalâ and hypervalent compounds are in moderate accord with experimental data, although in some instances large errors appear. Calculated energies relating to the stabilities of single and multiple bonds are in much better accord with the experimental energy differences
Effect of a LowâResource-Intensive Lifestyle Modification Program Incorporating Gymnasium-Based and Home-Based Resistance Training on Type 2 Diabetes Risk in Australian Adults
OBJECTIVEâThe purpose of this study was to assess the effectiveness of a lowâresource-intensive lifestyle modification program incorporating resistance training and to compare a gymnasium-based with a home-based resistance training program on diabetes diagnosis status and risk
A Network-Individual-Resource Model for HIV Prevention
HIV is transmitted through dyadic exchanges of individuals linked in transitory or permanent networks of varying sizes. A theoretical perspective that bridges key individual level elements with important network elements can be a complementary foundation for developing and implementing HIV interventions with outcomes that are more sustainable over time and have greater dissemination potential. Toward that end, we introduce a Network-Individual-Resource (NIR) model for HIV prevention that recognizes how exchanges of resources between individuals and their networks underlies and sustains HIV-risk behaviors. Individual behavior change for HIV prevention, then, may be dependent on increasing the supportiveness of that individualâs relevant networks for such change. Among other implications, an NIR model predicts that the success of prevention efforts depends on whether the prevention efforts (1) prompt behavior changes that can be sustained by the resources the individual or their networks possess; (2) meet individual and network needs and are consistent with the individualâs current situation/developmental stage; (3) are trusted and valued; and (4) target high HIV-prevalence networks
QualitĂ e grado di conservazione del paesaggio vegetale del litorale sabbioso del Veneto (Italia settentrionale).
Puberty is a complex physiological event by which animals mature into an adult capable of sexual reproduction. In order to enhance our understanding of the genes and regulatory pathways and networks involved in puberty, we characterized the transcriptome of five reproductive tissues (i.e. hypothalamus, pituitary gland, ovary, uterus, and endometrium) as well as tissues known to be relevant to growth and metabolism needed to achieve puberty (i.e., longissimus dorsi muscle, adipose, and liver). These tissues were collected from pre- and post-pubertal Brangus heifers (3/8 Brahman; Bos indicus x 5/8 Angus; Bos taurus) derived from a population of cattle used to identify quantitative trait loci associated with fertility traits (i.e., age of first observed corpus luteum (ACL), first service conception (FSC), and heifer pregnancy (HPG)). In order to exploit the power of complementary omics analyses, pre- and post-puberty co-expression gene networks were constructed by combining the results from genome-wide association studies (GWAS), RNA-Seq, and bovine transcription factors. Eight tissues among pre-pubertal and post-pubertal Brangus heifers revealed 1,515 differentially expressed and 943 tissue-specific genes within the 17,832 genes confirmed by RNA-Seq analysis. The hypothalamus experienced the most notable up-regulation of genes via puberty (i.e., 204 out of 275 genes). Combining the results of GWAS and RNA-Seq, we identified 25 loci containing a single nucleotide polymorphism (SNP) associated with ACL, FSC, and (or) HPG. Seventeen of these SNP were within a gene and 13 of the genes were expressed in uterus or endometrium. Multi-tissue omics analyses revealed 2,450 co-expressed genes relative to puberty. The pre-pubertal network had 372,861 connections whereas the post-pubertal network had 328,357 connections. A sub-network from this process revealed key transcriptional regulators (i.e., PITX2, FOXA1, DACH2, PROP1, SIX6, etc.). Results from these multi-tissue omics analyses improve understanding of the number of genes and their complex interactions for puberty in cattle
Receipt of Chemotherapy Among Medicare Patients With Cancer by Type of Supplemental Insurance
Medicare beneficiaries with cancer bear a greater portion of their health care costs, because cancer treatment costs have increased. Beneficiaries have supplemental insurance to reduce out-of-pocket costs; those without supplemental insurance may face barriers to care. This study examines the association between type of supplemental insurance coverage and receipt of chemotherapy among Medicare patients with cancer who, per National Comprehensive Cancer Network treatment guidelines, should generally receive chemotherapy
Selfâconsistent molecular orbital methods. XXIII. A polarizationâtype basis set for secondârow elements
The 6â31G* and 6â31G** basis sets previously introduced for firstârow atoms have been extended through the secondârow of the periodic table. Equilibrium geometries for oneâheavyâatom hydrides calculated for the twoâbasis sets and using HartreeâFock wave functions are in good agreement both with each other and with the experimental data. HF/6â31G* structures, obtained for twoâheavyâatom hydrides and for a variety of hypervalent secondârow molecules, are also in excellent accord with experimental equilibrium geometries. No large deviations between calculated and experimental single bond lengths have been noted, in contrast to previous work on analogous firstârow compounds, where limiting HartreeâFock distances were in error by up to a tenth of an angstrom. Equilibrium geometries calculated at the HF/6â31G level are consistently in better agreement with the experimental data than are those previously obtained using the simple splitâvalance 3â21G basis set for both normalâ and hypervalent compounds. Normalâmode vibrational frequencies derived from 6â31G* level calculations are consistently larger than the corresponding experimental values, typically by 10%â15%; they are of much more uniform quality than those obtained from the 3â21G basis set. Hydrogenation energies calculated for normalâ and hypervalent compounds are in moderate accord with experimental data, although in some instances large errors appear. Calculated energies relating to the stabilities of single and multiple bonds are in much better accord with the experimental energy differences
PKA phosphorylation activates the calcium release channel (ryanodine receptor) in skeletal muscle: defective regulation in heart failure
The type 1 ryanodine receptor (RyR1) on the sarcoplasmic reticulum (SR) is the major calcium (Ca2+) release channel required for skeletal muscle excitationâcontraction (EC) coupling. RyR1 function is modulated by proteins that bind to its large cytoplasmic scaffold domain, including the FK506 binding protein (FKBP12) and PKA. PKA is activated during sympathetic nervous system (SNS) stimulation. We show that PKA phosphorylation of RyR1 at Ser2843 activates the channel by releasing FKBP12. When FKB12 is bound to RyR1, it inhibits the channel by stabilizing its closed state. RyR1 in skeletal muscle from animals with heart failure (HF), a chronic hyperadrenergic state, were PKA hyperphosphorylated, depleted of FKBP12, and exhibited increased activity, suggesting that the channels are âleaky.â RyR1 PKA hyperphosphorylation correlated with impaired SR Ca2+ release and early fatigue in HF skeletal muscle. These findings identify a novel mechanism that regulates RyR1 function via PKA phosphorylation in response to SNS stimulation. PKA hyperphosphorylation of RyR1 may contribute to impaired skeletal muscle function in HF, suggesting that a generalized EC coupling myopathy may play a role in HF
Validity, Reliability, and Differential Item Functioning of English and French Versions of the 10-Item Connor-Davidson Resilience Scale in Systemic Sclerosis: A Scleroderma Patient-Centered Intervention Network Cohort Study
Objective
Some individuals with systemic sclerosis (SSc) report positive mental health, despite severe disease manifestations, which may be associated with resilience, but no resilience measure has been validated in SSc. This study was undertaken to assess the validity, reliability, and differential item functioning (DIF) between English- and French-language versions of the 10-item Connor-Davidson Resilience Scale (CD-RISC-10) in SSc.
Methods
Eligible participants were enrolled in the Scleroderma Patient-centered Intervention Network Cohort and completed the CD-RISC-10 between August 2022 and January 2023. We used confirmatory factor analysis (CFA) to evaluate the CD-RISC-10 factor structure and conducted DIF analysis across languages with Multiple Indicators Multiple Causes models. We tested convergent validity with another measure of resilience and measures of self-esteem and depression and anxiety symptoms. We assessed internal consistency and testâretest reliability using Cronbach\u27s alpha and intraclass correlation coefficient (ICC).
Results
A total of 962 participants were included in this analysis. CFA supported a single-factor structure (TuckerâLewis index = 0.99, comparative fit index = 0.99, root mean square error of approximation = 0.08 [90% confidence interval (90% CI) 0.07, 0.09]). We found no meaningful DIF. Internal consistency was high (α = 0.93 [95% CI 0.92, 0.94]), and we found that correlations with other measures of psychological functioning were moderate to large (|r| =â0.57â0.78) and confirmed study hypotheses. The scale showed good 1â2-week testâretest reliability (ICC 0.80 [95% CI 0.75, 0.85]) in a subsample of 230 participants.
Conclusion
The CD-RISC-10 is a valid and reliable measure of resilience in SSc, with score comparability across English and French versions
Oldest pathology in a tetrapod bone illuminates the origin of terrestrial vertebrates
The origin of terrestrial tetrapods was a key event in vertebrate evolution, yet how and when it occurred remains obscure, due to scarce fossil evidence. Here, we show that the study of palaeopathologies, such as broken and healed bones, can help elucidate poorly understood behavioural transitions such as this. Using high-resolution finite element analysis, we demonstrate that the oldest known broken tetrapod bone, a radius of the primitive stem tetrapod Ossinodus pueri from the mid-Viséan (333 million years ago) of Australia, fractured under a high-force, impact-type loading scenario. The nature of the fracture suggests that it most plausibly occurred during a fall on land. Augmenting this are new osteological observations, including a preferred directionality to the trabecular architecture of cancellous bone. Together, these results suggest that Ossinodus, one of the first large (>2m length) tetrapods, spent a significant proportion of its life on land. Our findings have important implications for understanding the temporal, biogeographical and physiological contexts under which terrestriality in vertebrates evolved. They push the date for the origin of terrestrial tetrapods further back into the Carboniferous by at least two million years. Moreover, they raise the possibility that terrestriality in vertebrates first evolved in large tetrapods in Gondwana rather than in small European forms, warranting a re-evaluation of this important evolutionary event
LSST: from Science Drivers to Reference Design and Anticipated Data Products
(Abridged) We describe here the most ambitious survey currently planned in
the optical, the Large Synoptic Survey Telescope (LSST). A vast array of
science will be enabled by a single wide-deep-fast sky survey, and LSST will
have unique survey capability in the faint time domain. The LSST design is
driven by four main science themes: probing dark energy and dark matter, taking
an inventory of the Solar System, exploring the transient optical sky, and
mapping the Milky Way. LSST will be a wide-field ground-based system sited at
Cerro Pach\'{o}n in northern Chile. The telescope will have an 8.4 m (6.5 m
effective) primary mirror, a 9.6 deg field of view, and a 3.2 Gigapixel
camera. The standard observing sequence will consist of pairs of 15-second
exposures in a given field, with two such visits in each pointing in a given
night. With these repeats, the LSST system is capable of imaging about 10,000
square degrees of sky in a single filter in three nights. The typical 5
point-source depth in a single visit in will be (AB). The
project is in the construction phase and will begin regular survey operations
by 2022. The survey area will be contained within 30,000 deg with
, and will be imaged multiple times in six bands, ,
covering the wavelength range 320--1050 nm. About 90\% of the observing time
will be devoted to a deep-wide-fast survey mode which will uniformly observe a
18,000 deg region about 800 times (summed over all six bands) during the
anticipated 10 years of operations, and yield a coadded map to . The
remaining 10\% of the observing time will be allocated to projects such as a
Very Deep and Fast time domain survey. The goal is to make LSST data products,
including a relational database of about 32 trillion observations of 40 billion
objects, available to the public and scientists around the world.Comment: 57 pages, 32 color figures, version with high-resolution figures
available from https://www.lsst.org/overvie
- âŠ