1,141 research outputs found
OSL surface exposure dating of a lithic quarry in Tibet: Laboratory validation and application
Preeclampsia is associated with compromized maternal synthesis of long chain polyunsaturated fatty acids leading to offspring deficiency
Obesity and excessive lipolysis are implicated in preeclampsia (PE). Intrauterine growth restriction is associated with low maternal body mass index and decreased lipolysis. Our aim was to assess how maternal and offspring fatty acid metabolism is altered in mothers in the third trimester of pregnancy with PE (n=62) or intrauterine growth restriction (n=23) compared with healthy pregnancies (n=164). Markers of lipid metabolism and erythrocyte fatty acid concentrations were measured. Maternal adipose tissue fatty acid composition and mRNA expression of adipose tissue fatty acid–metabolizing enzymes and placental fatty acid transporters were compared. Mothers with PE had higher plasma triglyceride (21%, P<0.001) and nonesterified fatty acid (50%, P<0.001) concentrations than controls. Concentrations of major n−6 and n−3 long-chain polyunsaturated fatty acids in erythrocytes were 23% to 60% lower (all P<0.005) in PE and intrauterine growth restriction mothers and offspring compared with controls. Subcutaneous adipose tissue Δ−5 and Δ−6 desaturase and very long-chain fatty acid elongase mRNA expression was lower in PE than controls (respectively, mean [SD] control 3.38 [2.96] versus PE 1.83 [1.91], P=0.030; 3.33 [2.25] versus 1.03 [0.96], P<0.001; 0.40 [0.81] versus 0.00 [0.00], P=0.038 expression relative to control gene [square root]). Low maternal and fetal long-chain polyunsaturated fatty acid concentrations in PE may be the result of decreased maternal synthesis
Improved Method of Neutron Activation Analysis for Microleakage Studies
Improvements in the neutron activation technique for studying microleakage were achieved by selecting more suitable tracers and by using a more accurate method for evaluation of the activation data. Dysprosium was the most suitable tracer; it provided the least variation in the results and allowed the fastest activation and counting procedure.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66594/2/10.1177_00220345740530022901.pd
Climate and environmental changes of the Lategacial transition and Holocene in northeastern Siberia: Evidence from diatom oxygen isotopes and assemblage composition at Lake Emanda
Indexación ScopusA new dataset from Lake Emanda provides insights into climate and environmental dynamics in an extreme continental setting in northeastern Siberia. The δ18Odiatom record is supported by diatom assemblage analysis, modern isotope hydrology and atmospheric circulation patterns. The data reveal a relatively cold oligotrophic freshwater lake system persisting for the last ∼13.2 cal ka BP. Most recent δ18Odiatom (+21.5‰) combined with present-day average δ18Olake (−16.5‰) allows calculating Tlake (∼21 °C), reflecting summer conditions. Nonetheless, the δ18Odiatom variability is associated with changes in δ18Olake rather than with Tlake. An obvious shift of ∼2‰ in the δ18Odiatom record at 11.7–11.5 cal ka BP accompanied by significant changes in diatom assemblages reflects the onset of the Holocene. Relatively high δ18Odiatom during the Early Holocene suggests relatively warm and/or dry climate with associated evaporation effects. The absolute maximum in δ18Odiatom of +27.7‰ consistent with high values of diatom indices at ∼7.9–7.0 cal ka BP suggests a Mid Holocene Thermal Maximum. A continuous depletion in δ18Odiatom since ∼5.0 cal ka BP is interpreted as Middle to Late Holocene cooling reaching the absolute minimum at 0.4 cal ka BP (i.e. the Little Ice Age). An overall cooling trend (∼0.3‰ 1000 yr−1) throughout the Holocene follows decreasing solar insolation. The pattern of the Lake Emanda δ18Odiatom record is similar to that obtained from Lake El'gygytgyn suggesting a common “eastern” regional signal in both records, despite their hydrological differences. Presently, atmospheric moisture reaches the study region from the west and east with ∼40% each, as well as ∼20% from the north. © 2021 The Author(s)https://www-sciencedirect-com.recursosbiblioteca.unab.cl/science/article/pii/S0277379121001128?via%3Dihu
Comparative toxicity and effectiveness of trastuzumab-based chemotherapy regimens in older women with early-stage breast cancer
Purpose The combination of chemotherapy and trastuzumab is the standard of care for adjuvant treatment of human epidermal growth factor receptor 2-positive breast cancer. Two regimens have been widely adopted in the United States: doxorubicin, cyclophosphamide, paclitaxel, and trastuzumab (ACTH) and docetaxel, carboplatin, and trastuzumab (TCH). No head-to-head comparison of these regimens has been conducted in a clinical trial, and existing trial data have limited generalizability to older patients. Methods We used SEER-Medicare data from 2005 to 2013 to compare outcomes of ACTH versus TCH among patients age older than 65 years. Propensity score matching was used to balance cohort characteristics between treatment arms. Outcomes included toxicity-related hospitalization, survival, and trastuzumab completion. Data from 1,077 patients receiving ACTH or TCH were analyzed, and the propensity-matched subsample included 416 women. Results There was a significant shift toward TCH over time, with 88% of patients receiving ACTH in 2005 compared with 15% by 2011. Among propensity score-matched patients, we found no difference between regimens in health care use overall or for chemotherapy-related adverse events (ACTH, 34% v TCH, 36.5%; P = .46). Patients receiving TCH were significantly more likely to complete trastuzumab (89% v 77%; P = .001). There was no difference in 5-year breast cancer-specific survival (ACTH, 92% v TCH, 96%; hazard ratio, 2.08; 95% CI, 0.90 to 4.82) or overall survival. Conclusion Among a matched sample of older patients, ACTH compared with TCH was not associated with a higher rate of serious adverse events or hospitalizations, but it was associated with less completion of adjuvant trastuzumab.Wedid not detect a difference in 5-year survival outcomes for ACTH compared with TCH. In the context of limited evidence in older patients, selection between these two regimens on the basis of concerns about differential toxicity or efficacy may not be appropriate
The Importance of Time Congruity in the Organisation.
In 1991 Kaufman, Lane, and Lindquist proposed that time congruity in terms of an individual's time preferences and the time use methods of an organisation would lead to satisfactory performance and enhancement of quality of work and general life. The research reported here presents a study which uses commensurate person and job measures of time personality in an organisational setting to assess the effects of time congruity on one aspect of work life, job-related affective well-being. Results show that time personality and time congruity were found to have direct effects on well-being and the influence of time congruity was found to be mediated through time personality, thus contributing to the person–job (P–J) fit literature which suggests that direct effects are often more important than indirect effects. The study also provides some practical examples of ways to address some of the previously cited methodological issues in P–J fit research
Swiss Frailty Network and Repository: protocol of a Swiss Personalized Health Network's driver project observational study.
Early identification of frailty by clinical instruments or accumulation of deficit indexes can contribute to improve healthcare for older adults, including the prevention of negative outcomes in acute care. However, conflicting evidence exists on how to best capture frailty in this setting. Simultaneously, the increasing utilisation of electronic health records (EHRs) opens up new possibilities for research and patient care, including frailty.
The Swiss Frailty Network and Repository (SFNR) primarily aims to develop an electronic Frailty Index (eFI) from routinely available EHR data in order to investigate its predictive value against length of stay and in-hospital mortality as two important clinical outcomes in a study sample of 1000-1500 hospital patients aged 65 years and older. In addition, we will examine the correlation between the eFI and a test-based clinical Frailty Instrument to compare both concepts in Swiss older adults in acute care settings. As a Swiss Personalized Health Network (SPHN) driver project, our study will report on the characteristics and usability of the first nationwide eFI in Switzerland connecting all five Swiss University Hospitals' Geriatric Departments with a representative sample of patients aged 65 years and older admitted to acute care.
The study protocol was approved by the competent ethics committee of the Canton of Zurich (BASEC-ID 2019-00445). All acquired data will be handled according to SPHN's ethical framework for responsible data processing in personalised health research. Analyses will be performed within the secure BioMedIT environment, a national infrastructure to enable secure biomedical data processing, an integral part of SPHN.
NCT04516642
On the Potts model partition function in an external field
We study the partition function of Potts model in an external (magnetic)
field, and its connections with the zero-field Potts model partition function.
Using a deletion-contraction formulation for the partition function Z for this
model, we show that it can be expanded in terms of the zero-field partition
function. We also show that Z can be written as a sum over the spanning trees,
and the spanning forests, of a graph G. Our results extend to Z the well-known
spanning tree expansion for the zero-field partition function that arises
though its connections with the Tutte polynomial
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