Different decompositions (sum rules) for the proton mass have been proposed in the literature. All of them are related to the energy-momentum tensor in quantum chromodynamics. We review and revisit ...these decompositions by paying special attention to recent developments with regard to the renormalization of the energy-momentum tensor. The connection between the sum rules is discussed as well. We present numerical results for the various terms of the mass decompositions up to three loops in the strong coupling, and consider their scheme dependence. We also elaborate on the role played by the trace anomaly and the sigma terms.
Within the collinear twist-3 framework, we study the single-spin asymmetry (SSA) in collisions between unpolarized protons and transversely polarized protons with focus on the fragmentation term. The ...fragmentation mechanism must be analyzed in detail in order to unambiguously determine the impact of various contributions to SSAs in hadron production. Such a distinction may also settle the “sign mismatch” between the transverse SSA in proton–proton collisions and the Sivers effect in semi-inclusive deep inelastic scattering. We calculate terms involving quark–quark and quark–gluon–quark correlators, which is an important step in such an investigation.
Research efforts during the past decades have provided intriguing evidence suggesting that stressful experiences during pregnancy exert long-term consequences on the future mental wellbeing of both ...the mother and her baby. Recent human epidemiological and animal studies indicate that stressful experiences in utero or during early life may increase the risk of neurological and psychiatric disorders, arguably via altered epigenetic regulation. Epigenetic mechanisms, such as miRNA expression, DNA methylation, and histone modifications are prone to changes in response to stressful experiences and hostile environmental factors. Altered epigenetic regulation may potentially influence fetal endocrine programming and brain development across several generations. Only recently, however, more attention has been paid to possible transgenerational effects of stress. In this review we discuss the evidence of transgenerational epigenetic inheritance of stress exposure in human studies and animal models. We highlight the complex interplay between prenatal stress exposure, associated changes in miRNA expression and DNA methylation in placenta and brain and possible links to greater risks of schizophrenia, attention deficit hyperactivity disorder, autism, anxiety- or depression-related disorders later in life. Based on existing evidence, we propose that prenatal stress, through the generation of epigenetic alterations, becomes one of the most powerful influences on mental health in later life. The consideration of ancestral and prenatal stress effects on lifetime health trajectories is critical for improving strategies that support healthy development and successful aging.
The gestational state is a period of particular vulnerability to diseases that affect maternal and fetal health. Stress during gestation may represent a powerful influence on maternal mental health ...and offspring brain plasticity and development. Here we show that the fetal transcriptome, through microRNA (miRNA) regulation, responds to prenatal stress in association with epigenetic signatures of psychiatric and neurological diseases. Pregnant Long-Evans rats were assigned to stress from gestational days 12 to 18 while others served as handled controls. Gestational stress in the dam disrupted parturient maternal behaviour and was accompanied by characteristic brain miRNA profiles in the mother and her offspring, and altered transcriptomic brain profiles in the offspring. In the offspring brains, prenatal stress upregulated miR-103, which is involved in brain pathologies, and downregulated its potential gene target Ptplb. Prenatal stress downregulated miR-145, a marker of multiple sclerosis in humans. Prenatal stress also upregulated miR-323 and miR-98, which may alter inflammatory responses in the brain. Furthermore, prenatal stress upregulated miR-219, which targets the gene Dazap1. Both miR-219 and Dazap1 are putative markers of schizophrenia and bipolar affective disorder in humans. Offspring transcriptomic changes included genes related to development, axonal guidance and neuropathology. These findings indicate that prenatal stress modifies epigenetic signatures linked to disease during critical periods of fetal brain development. These observations provide a new mechanistic association between environmental and genetic risk factors in psychiatric and neurological disease.
This study compared the relationship of parenting styles to the career decision-making of adolescents from a Western and an Eastern context. Specifically, 575 French high school students and 613 ...South Korean high school students completed a questionnaire assessing perceived parenting style, career decision-making difficulties, and career decision self-efficacy. The Korean adolescents had lower career decision self-efficacy beliefs and higher career decision-making difficulties than the French adolescents. The authoritarian parenting style was associated with higher scores on career decision self-efficacy and lower scores on a measure of career decision-making difficulties in the Korean sample while the authoritative parenting style was associated with higher scores on career decision self-efficacy and lower scores on a measure of career decision-making difficulties in the French sample. Results showed significant effects for gender and parenting style on the career decision-making outcomes of both samples.
•Parenting style can significantly impact career decision-making variables.•Parenting style may differ for students raised in a Western and an Eastern context.•Korean students reported more career decision difficulties than French students.•Authoritative parenting style correlated positively with CDSE for French students.•Authoritarian parenting style correlated positively with CDSE for Korean students.
Ice retreat in West Antarctica and Antarctic Peninsula has led to important changes in seafloor communities and gains in benthic blue carbon. In most of the Antarctic, however, sea ice increased ...between the 1970s and 2014, but its effects on the benthos remain largely unexplored. Here, we provide a 1988-2014 record of macro- and megafauna from the north-eastern Weddell Sea shelf, where benthic biomass decreased by two thirds and composition shifted from suspension feeders to deposit feeders. Concomitant increases in sea-ice cover suggest a reduced flux of primary production to the benthos. As benthic communities are major repositories for Antarctic biodiversity and play an important role in biogeochemical cycling, the observed changes have far-reaching consequences for the Antarctic ecosystem and its feedback to the climate system. The findings underscore the importance of long-term ecological monitoring in a region vulnerable to warming and ice-shelf collapse.
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bstract
Different decompositions of the nucleon mass, in terms of the masses and energies of the underlying constituents, have been proposed in the literature. We explore the corresponding sum ...rules in quantum electrodynamics for an electron at one-loop order in perturbation theory. To this aim we compute the form factors of the energy-momentum tensor, by paying particular attention to the renormalization of ultraviolet divergences, operator mixing and scheme dependence. We clarify the expressions of all the proposed sum rules in the electron rest frame in terms of renormalized operators. Furthermore, we consider the same sum rules in a moving frame, where they become energy decompositions. Finally, we discuss some implications of our study on the mass sum rules for the nucleon.
Stress is among the primary causes of mental health disorders, which are the most common reason for disability worldwide. The ubiquity of these disorders, and the costs associated with them, lends a ...sense of urgency to the efforts to improve prediction and prevention. Down-stream metabolic changes are highly feasible and accessible indicators of pathophysiological processes underlying mental health disorders. Here, we show that remote and cumulative ancestral stress programs central metabolic pathways linked to mental health disorders. The studies used a rat model consisting of a multigenerational stress lineage (the great-great-grandmother and each subsequent generation experienced stress during pregnancy) and a transgenerational stress lineage (only the great-great-grandmother was stressed during pregnancy). Urine samples were collected from adult male F4 offspring and analyzed using
1
H NMR spectroscopy. The results of variable importance analysis based on random variable combination were used for unsupervised multivariate principal component analysis and hierarchical clustering analysis, as well as metabolite set enrichment analysis (MSEA) and pathway analysis. We identified distinct metabolic profiles associated with the multigenerational and transgenerational stress phenotype, with consistent upregulation of hippurate and downregulation of tyrosine, threonine, and histamine. MSEA and pathway analysis showed that these metabolites are involved in catecholamine biosynthesis, immune responses, and microbial host interactions. The identification of metabolic signatures linked to ancestral programming assists in the discovery of gene targets for future studies of epigenetic regulation in pathogenic processes. Ultimately, this research can lead to biomarker discovery for better prediction and prevention of mental health disorders.
Stress is one of the most critical determinants of lifetime health and increases the risk of chronic non-communicable diseases. To gain insight into underlying environment-gene interactions, we ...analyzed the cardiorenal metabolome of adult mice exposed to multidimensional early-life transportation stress. Using proton nuclear magnetic resonance (
H NMR) spectroscopy, we show that early life stress permanently programs metabolic pathways in somatic organs linked to cardiorenal and mental health disorders in later life. Heart and kidneys of stressed mice revealed robust metabolic markers linked to abnormal energy metabolism, branched-chain amino acid biosynthesis and degradation, methylhistidine metabolism, arginine and proline metabolism, glycine and serine metabolism, and aminoacyl-tRNA biosynthesis. These markers were strongly associated with anxiety-like behaviours. Dysregulation of energy and protein metabolism suggests an increased risk of metabolic diseases like insulin resistance, cardiorenal syndrome, diabetes, and obesity. These findings provide novel insights into the direct effects of early life stress on cardiorenal metabolism and are consistent with prior observations of increased non-communicable disease risk in stressed populations. Thus, stress-associated metabolic signatures in somatic organs may provide early predictors of health risks in later life and reveal new candidates for peripheral biomarker detection with diagnostic value.
Endoscopic mucosal resection (EMR) for large colonic laterally spreading tumors (LSTs) is a safe, efficacious, and cost-effective treatment. The most common serious complication is delayed bleeding, ...which reduces these advantages, but consensus guidelines for large-polyp EMR do not exist.
Data from two large prospective intention-to-treat studies of EMR for colonic LSTs 20 mm or greater in size were analyzed. Data collection was comprehensive, and included patient and lesion characteristics. EMR technique and cessation of anticoagulant and antiplatelet therapy was standardized. Clinically significant delayed bleeding was defined as that requiring hospital admission.
EMR was performed on 302 lesions in 288 patients. There was clinically significant delayed bleeding in 21 cases (7 %). Ten underwent colonoscopy. One required angiography. One required surgery after perforation following hemostatic clip placement. There were no deaths. Risk factors for bleeding on multivariate analysis were right colon location adjusted odds ratio (OR) 4.4, P = 0.01, use of aspirin (OR 6.3, P = 0.005), and age (OR per decade of age 1.70). All bleeds occurred before aspirin was restarted. Patient characteristics, including ASA grade and co-morbidity type, were not predictive. Despite requiring more complex EMR, larger lesion size ( P = 0.2), multiple excisions rather than en bloc resection ( P = 0.1), polyp morphology ( P = 0.2), and previous attempts ( P = 0.5), were not associated with increased risk.
Proximal lesion location is a highly significant risk for clinically significant delayed bleeding following colonic EMR, and this knowledge could form the basis of a targeted therapeutic trial. Recent aspirin use also increases bleeding risk--specific consensus guidelines in this area are required for colonic EMR.
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