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Social media sites like Twitter (now X) are increasingly used to create health behavior metrics for public health surveillance. Yet little is known about social norms that may bias the content of posts about health behaviors. Social norms for posts about four health behaviors (smoking tobacco, drinking alcohol, physical activity, eating food) on Twitter/X were evaluated. This was a randomized experiment delivered via web-based survey to adult, English-speaking Twitter/X users in three Michigan, USA, counties from 2020 to 2022 (n =559). Each participant viewed 24 posts presenting experimental manipulations regarding four health behaviors and answered questions about each post's social acceptability. Principal component analysis was used to combine survey responses into one perceived social acceptability measure. Linear mixed models with the Benjamini–Hochberg correction were implemented to test seven study hypotheses in 2023. Supporting six hypotheses, posts presenting healthier (CI: 0.028, 0.454), less stigmatized behaviors (CI: 0.552, 0.157) were more socially acceptable than posts regarding unhealthier, stigmatized behaviors. Unhealthy (CI: −0.268, −0.109) and stigmatized behavior (CI: −0.261, −0.103) posts were less acceptable for more educated participants. Posts about collocated activities (CI: 0.410, 0.573) and accompanied by expressions of liking (CI: 0.906, 1.11) were more acceptable than activities undertaken alone or disliked. Contrary to one hypothesis, posts reporting unusual activities were less acceptable than usual ones (CI: −0.472, 0.312). Perceived social acceptability may be associated with the frequency and content of health behavior posts. Users of Twitter/X and other social media platform posts to estimate health behavior prevalence should account for potential estimation biases from perceived social acceptability of posts. [ABSTRACT FROM AUTHOR]

In many regions of the world, land conversion of native plant communities to non-native pastures is usually associated with significant changes in soil nutrient contents. In Mexico, more than one million hectares of drylands have been converted to non-native pastures, with little knowledge on the biogeochemical consequences. We investigated the effects of non-native buffelgrass ( Pennisetum ciliare ) pasture conversion on soil carbon (C), nitrogen (N) and phosphorus (P) dynamics to understand the effects of disturbance on soil nutrient in a region of the state of Sonora. Eleven sites that formed a gradient (1–44 years) of buffelgrass establishment history where buffelgrass establishment has been practiced for at least 50 years, were studied. Soil organic C, total N and P, microbial biomass C, extractable P, and mineral N contents and basal soil respiration, were measured in samples collected during the dry and rainy seasons in buffelgrass pastures and undisturbed thornscrub. Conversion to buffelgrass pastures decreased mineral N content and basal soil respiration. Extractable P decreased in older pastures (>10 years), suggesting a potential P-limitation for the permanence of long-term buffelgrass pastures in Sonora. In contrast, we did not detect a significant reduction of soil organic C, total N and P in older pastures. This study suggests that P limitation may serve as important controls on ecosystem nutrient cycling in natural vegetation and recovery of these thornscrubs after buffelgrass pasture establishment for cattle ranching. [ABSTRACT FROM AUTHOR]

Abstract: Background: T-wave alternans (TWA) is associated with prognosis after myocardial infarction (MI), however its link to the extent of ischemic injury has not been clarified. We analyzed the course of TWA and its relation to myocardial damage in experimental myocardial infarction. Methods: In 21 pigs, infarction was induced by 40-minute long balloon inflation in LAD under continuous 12-lead ECG monitoring. TWA was assessed in a 32-beat sliding window, using periodic component analysis and the Laplacian Likelihood Ratio method. Myocardium at risk (MaR) and infarct size (IS) were evaluated by SPECT and magnetic resonance imaging respectively. Results: TWA appeared at 7.2±4.5minutes of occlusion, reached its maximum at 12.7±6.3 and lasted until 26.5±9.2minutes. The maximal level of TWA was associated with both MaR (r=0.499, p=0.035) and IS (r=0.65, p=0.004). Conclusion: TWA magnitude is associated with both MaR and IS in experiment, which encourages further studies in clinical settings. [Copyright &y& Elsevier]

Abstract: Objective: In acute myocardial ischemia changes within the QRS complex can add valuable information to that from the repolarization phase. This study evaluates three angles obtained from the main slopes of the R-wave within the QRS complex to assess acute myocardial ischemia. Methods: The QRS angles, denoted by ØR (R-wave angle), ØU (up-stroke angle) and ØD (down-stroke angle), were evaluated in 12-lead electrocardiogram (ECG) recordings of 79 patients before and during coronary occlusion by elective percutaneous coronary intervention (PCI). In a subset of 38 patients, ischemia was quantified by myocardial scintigraphy. Results: At baseline the QRS angles presented low variations. During occlusion, ØU and ØD developed a fast and abrupt change, whereas ØR showed a smaller and gradual change. There were significant correlations between both maximal and sum of positive change in ØR and ischemia: r=0.67; p<0.001 and r=0.78; p<0.001, for extent, and r=0.60; p<0.001 and r=0.73; p<0.001, for severity, respectively. Prediction of extent and severity of ischemia increased by 50% by adding ØR changes to ST-segment changes, for LCX occlusions, whereas increased by 12.1% and 24.6% for LAD and RCA occlusions, respectively. No significant correlation was seen between ØU and ØD angles and ischemia. Conclusions: Evaluation of QRS angles from the standard 12-lead ECG represents a sensitive marker for detection of acute myocardial ischemia, whereas, ØR changes can be used for prediction of its extent and severity. [Copyright &y& Elsevier]

Abstract: Objective: This study evaluates depolarization changes in acute myocardial ischemia by analysis of QRS slopes. Methods: In 38 patients undergoing elective percutaneous coronary intervention, changes in upward slope between Q and R waves and downward slope between R and S waves (DS) were analyzed. In leads V1 to V3, upward slope of the S wave was additionally analyzed. Ischemia was quantified by myocardial scintigraphy. Also, conventional QRS and ST measures were determined. Results: QRS slope changes correlated significantly with ischemia (for DS: r = 0.71, P < .0001 for extent, and r = 0.73, P < .0001 for severity). Best corresponding correlation for conventional electrocardiogram parameters was the sum of R-wave amplitude change (r = 0.63, P < .0001; r = 0.60, P < .0001) and the sum of ST-segment elevation (r = 0.67, P < .0001; r = 0.73, P < .0001). Prediction of extent and severity of ischemia increased by 12.2% and 7.1% by adding DS to ST. Conclusions: The downward slope between R and S waves correlates with ischemia and could have potential value in risk stratification in acute ischemia in addition to ST-T analysis. [Copyright &y& Elsevier]

Telomeric DNA – the short, tandemly repeated sequences at the ends of chromosomes – is synthesized by telomerase, a ribonucleoprotein enzyme that copies a specific template sequence within its integral RNA moiety. The error-prone telomerase from the ciliate Paramecium tetraurelia stereotypically misincorporates TTP at telomerase RNA templating nucleotide C52, accounting for the 30% TTTGGG repeats randomly distributed in wild-type telomeres. Paramecium tetraurelia telomerase has been isolated from macronuclear extracts and characterized with respect to the extension of telomeric primers in vitro. Unlike telomerase activities from other species, the predominant pause during telomeric repeat synthesis by P. tetraurelia telomerase does not occur at the 5′ end of the templating domain (templating nucleotide C49). Instead, the pause by P. tetraurelia telomerase is at templating nucleotide C53, immediately prior to incorporation of dGTP (or TTP) at C52. The configuration of the catalytic site at this template position during telomere synthesis is most likely responsible for the high incidence of misincorporation of TTP at C52. The gene for the P. tetraurelia telomerase catalytic subunit, telomerase reverse transcriptase (TERT), has been cloned and sequenced. A comparative analysis of the P. tetraurelia TERT with homologs from other species, including that from another Paramecium species that does not make a high percentage of misincorporation errors, has been initiated. This study may delineate those TERT structural elements that contribute to telomerase fidelity. [Copyright &y& Elsevier]

Abstract: A novel score-level fusion strategy based on Bayesian adaptation for user-dependent multimodal biometric authentication is presented. In the proposed method, the fusion function is adapted for each user based on prior information extracted from a pool of users. Experimental results are reported using on-line signature and fingerprint verification subsystems on the MCYT real bimodal database. The proposed scheme outperforms both user-independent and user-dependent standard approaches. As compared to non-adapted user-dependent fusion, relative improvements of and are obtained for small and large training set sizes, respectively. [Copyright &y& Elsevier]

Cervical vestibular evoked myogenic potentials (cVEMPs) are surface-recorded responses that reflect saccular function. Analysis of cVEMPs has focused, nearly exclusively, on time-domain waveform measurements such as amplitude and latency of response peaks, but synchrony-based measures have not been previously reported. Time-frequency analyses were used to apply an objective response-detection algorithm and to quantify response synchrony. These methods are new to VEMP literature and have been adapted from previous auditory research. Air-conducted cVEMPs were elicited using a 500 Hz tone burst in twenty young, healthy participants. Time-frequency characteristics of cVEMPs and time-frequency boundaries for response energy were established. An inter-trial coherence analysis approach revealed highly synchronous responses with representative inter-trial coherence values of approximately 0.7. Inter-trial coherence measures were highly correlated with conventional amplitude measures in this group of young, healthy adults (R 2 = 0.91 – 0.94), although the frequencies at which these measures had their largest magnitude were unrelated (R 2 =.02). Conventional measures of peak-to-peak amplitude and latency were consistent with previous literature. Interaural asymmetry ratios were comparable between amplitude- and synchrony-based measures. Synchrony-based time-frequency analyses were successfully applied to cVEMP data and this type of analysis may be helpful to differentiate synchrony from amplitude in populations with disrupted neural synchrony. • Cervical vestibular evoked myogenic potentials (cVEMPs) reflect otolith function. • cVEMPs were elicited with transient tonebursts. • intertrial coherence were applied to measure response synchrony. • cVEMPs were revealed to be highly synchronous. • intertrial coherence is a feasible analysis for cVEMPs. [ABSTRACT FROM AUTHOR]

Abstract: This paper develops a Rewriting Logic framework for the automatic specification and verification of Web applications that considers the critical aspects of concurrent Web interactions, browser navigation features (e.g., forward/back-ward navigation, page refresh, and new window/tab opening), and Web script evaluation. By encompassing the main features of the most popular Web scripting languages (e.g., PHP, ASP, and Java Servlets), our scripting language is powerful enough to model the dynamics of complex Web applications, where the interactions among Web servers and Web browsers are formalized through a landmark communicating protocol that abstracts HTTP. We provide a detailed characterization of browser actions via rewrite rules and show how our models can be naturally model-checked by using the Linear Temporal Logic of Rewriting (LTLR), which is a Linear Temporal Logic that is specifically designed for model-checking rewrite theories. The framework has been completely implemented in Maude, and we report on some successful experiments that we conducted using the Maude LTLR model-checker. [Copyright &y& Elsevier]

Abstract: Understanding the behavior of software is important for the existing software to be improved. In this paper, we present a trace slicing technique that is suitable for analyzing complex, textually-large computations in rewriting logic, which is a general framework efficiently implemented in the Maude language that seamlessly unifies a wide variety of logics and models of concurrency. Given a Maude execution trace and a slicing criterion for the trace (i.e., a piece of information that we want to observe in the final computation state), we traverse from back to front and the backward dependence of the observed information is incrementally computed at each execution step. At the end of the traversal, a simplified trace slice is obtained by filtering out all the irrelevant data that do not impact on the data of interest. By narrowing the size of the trace, the slicing technique favors better inspection and debugging activities since most tedious and irrelevant inspections that are routinely performed during diagnosis and bug localization can be eliminated automatically. Moreover, cutting down the execution trace can expose opportunities for further improvement, which we illustrate by means of several examples that we execute by using iJulienne, a trace slicer that implements our conditional slicing technique and is endowed with a trace querying mechanism that increases flexibility and reduction power. [Copyright &y& Elsevier]

Abstract: Keeping XML data in a consistent state w.r.t. both structure and content is a burdensome task. To maintain the consistency of ever-larger, complex XML repositories, suitable mechanisms that are able to fix every possible inconsistency are needed. In this article, we present a methodology for semi-automatically repairing faulty XML repositories that can be integrated on top of an existing rewriting-based verification engine. As a formal basis for representing consistency criteria, we use a rule-based description formalism that is realized in the language Maude. Then, starting from a categorization of the kinds of errors that can be found during the verification process, we formulate a stepwise transformation procedure that achieves correctness and completeness of the XML repository w.r.t. its Maude formal specification while strictly observing the structure of the XML documents. With the aim of increasing the level of automation of our repair methodology, we also define two correction strategies and two completion strategies that reduce either the amount of information to be changed or the number of repair actions to be executed in order to deliver an XML repository that is both correct and complete. Finally, we describe a prototype implementation of the repairing tool, which we use for an experimental evaluation of our method with good results. [Copyright &y& Elsevier]

Abstract: We analyzed the role of the cannabinoid system in the cognitive deficits caused by developmentally-induced hypothyroidism. We studied in control and hypothyroid rats the effect of a cannabinoid agonist on spatial memory, hippocampal phosphorylation of CREB and expression of early genes. Our results show that, 1-basal hippocampal expression of early genes and spatial learning are decreased in hypothyroid rats; 2-hypothyroid rats are very sensitive to cannabinoid agonists. Low dose of cannabinoid agonist ineffective in controls altered spatial memory, CREB’s phosphorylation and early gene expression in hypothyroids. These effects are not due a change in CB1 receptor (CB1R) content. 3-Treatment of hypothyroid rats with thyroid hormones normalized the biochemical and behavioral responses to cannabinoid agonists but did not correct the low basal levels of early gene transcripts and the deficits in spatial learning. All these data suggest that the hippocampal deregulation of early genes expression could play an important role in the basal cognitive deficits of hypothyroid rats. [Copyright &y& Elsevier]

Background Breast cancer is the main type of cancer that affects women in Colombia. There are still some factors that limit the survival of this population. Describing individuals with advanced disease will allow identifying those factors that influence the course of care for these patients. Methods Descriptive cross-sectional study with patients coming from registers of two oncology centres in northeastern Colombia during the period 2010 - 2017. An analysis of central tendency, univariate and bivariate measures were performed, and comparisons of proportions with Chi-square (p < 0,05) were assessed. Interim Results We included 227 patients with a diagnosis of invasive breast cancer. The average age at diagnosis of cancer and metastasis was 53.7 and 55.9 years, respectively (2.2 years between events). The most frequent sites of metastasis were bone (43%), lung-pleura (20.4%) and liver (10.7%). There was metastasis in skin, ganglia and brain in approximately 7% each. 88%(165) of the patients presented invasive ductal cancer, the average Ki67 was 30%, and the luminal A subtype was present in 41% (68). Non-ductal variants were associated with metastasis from the first consultation. 28% of patients died during the observation period (7 years). Conclusion this is the first description of the behaviour of metastatic breast cancer in a large group of patients in Colombia. The ductal variant, luminal A, high grade, high proliferative index and bone metastasis were the most common characteristics found in women with advanced disease included in this study. [ABSTRACT FROM AUTHOR]