Analysis of observations of the middle atmosphere from satellites

Satellite data are being used to investigate problems in middle atmosphere chemistry and dynamics. Efforts have been focused primarily on studies to determine the quality of observed distributions of trace species and derived dynamical quantities. Those data have been used as diagnostics for model-derived constituent profiles and fields and for improving our understanding of some of the fundamental processes occurring in the middle atmosphere. Temperatures and derived winds from Nimbus 7 Limb Infrared Monitoring of the Stratosphere (LIMS) data were compared with long-time series of rawinsonde data at Invercargill, New Zealand, and Berlin, West Germany, and the results are excellent for both quantities. It was also demonstrated that more highly-derived dynamical quantities can be obtained reliably from those LIMS fields. Furthermore, both the diabatic and residual-mean circulations derived using LIMS data agree qualitatively with changes in the distribution of trace species determined independently with the Nimbus 7 SAMS and LIMS experiments. Subsequently, an examination of LIMS data at mid to high latitudes of the Southern Hemisphere has revealed a synoptic-scale, upper stratospheric instability during late autumn that is associated with the development of the stratospheric polar jet. Investigation of this phenomenon continues with Stratospheric Sounding Unit (SSU) data sets

Syncope and Early Repolarization: A Benign or Dangerous ECG Finding?

Early repolarization is a well-described, common electrocardiographic variant. It was initially felt to be benign, but in the last twenty years a suggested a link between specific types of early repolarization and sudden cardiac death has emerged. This association was has been termed the J wave syndrome and includes both the high risk early repolarization and Brugada ECG patterns. The odds of early repolarization change being associated with poor outcomes are still exceedingly small. Nevertheless, the association of a fairly ubiquitous ECG finding with fatal or near fatal clinical outcomes has raised concern. How can we identify the truly high-risk patients? If a patient has a significant clinical event with a concerning ECG repolarization pattern, what should be done next? The authors of this review present current information regarding the Early Repolarization and Brugada Syndromes and how to proceed with diagnosis, management, and risk stratification when early repolarization change is observed on ECG

EVERYTHING COUNTS: Building a Control Regime for Nonstrategic Nuclear Warheads in Europe

Before the Russian invasion of Ukraine, the Biden administration insisted in arms control talks with Russia that a follow-on agreement to the New Strategic Arms Reduction Treaty (New START) should cover all nuclear weapons and that such an agreement should focus on the nuclear warheads themselves. This would represent a significant change from previous agreements, which focused on delivery vehicles, such as missiles. The United States has been particularly interested in potential limits on nonstrategic nuclear warheads (NSNW). Such weapons have never been subject to an arms control agreement. Because Russia possesses an advantage in the number of such weapons, the US Senate has insisted that negotiators include them in a future agreement, making their inclusion necessary if such an accord is to win Senate approval and ultimately be ratified by Washington. In the wake of Russian nuclear threats in the Ukraine conflict, such demands can only be expected to grow if and when US and Russian negotiators return to the negotiating table

The Subcutaneous Implantable Cardioverter-Defibrillator: A Practical Review and Real-World Use and Application

The subcutaneous implantable cardioverter-defibrillator (ICD) is a novel technology using a subcutaneous (extrathoracic) system for treatment of potential lethal ventricular arrhythmias. It avoids many of the risks of transvenous ICD implantation. It may be considered in patients having an ICD indication who do not have a pacing and/or cardiac resynchronization therapy indication, and who are unlikely to benefit from antitachycardia pacing therapy. We review patient selection, system components, the implantation technique, and screening considerations for subcutaneous ICD implantation. Its uses in specific patient populations, including children, patients with congenital heart disease, hypertrophic cardiomyopathy, or end-stage renal disease, and patients with preexisting pacemakers, are highlighted. Areas of future investigation are reviewed, including potential use with leadless pacing and magnetic resonance imaging

Principles of Arrhythmia Management During Pregnancy

This paper reviews current recommendations on the appropriate evaluation and management of cardiac arrhythmias in the pregnant patient. Most arrhythmias during pregnancy are benign and require no intervention. When required, the decision to treat should be based on symptom severity and the associated risk to mother and fetus posed by potentially recurring arrhythmia episodes throughout the pregnancy. Any treatment strategy in this patient population has inherent risk to both mother and unborn child. Before the initiation of any intervention, documentation of a clinical arrhythmia and correlation with clinical symptoms should be obtained. There is no role for empiric therapy

The impact of changing attitudes, norms, and self-efficacy on health-related intentions and behavior: a meta-analysis

Objective: Several health behavior theories converge on the hypothesis that attitudes, norms, and self-efficacy are important determinants of intentions and behavior. Yet inferences regarding the relation between these cognitions and intention or behavior rest largely on correlational data that preclude causal inferences. To determine whether changing attitudes, norms, or self-efficacy leads to changes in intentions and behavior, investigators need to randomly assign participants to a treatment that significantly increases the respective cognition relative to a control condition, and test for differences in subsequent intentions or behavior. The present review analyzed findings from 204 experimental tests that met these criteria. Methods: Studies were located using computerized searches and informal sources and meta-analyzed using STATA Version 11. Results: Experimentally induced changes in attitudes, norms, and self-efficacy all led to medium-sized changes in intention (d+ = .48, .49, and .51, respectively), and engendered small to medium-sized changes in behavior (attitudes-d+ = .38; norms-d+ = .36; self-efficacy-d+ = .47). These effect sizes generally were not qualified by the moderator variables examined (e.g., study quality, theoretical basis of the intervention, methodological characteristics, features of the targeted behavior), although effects were larger for interventions designed to increase (vs. decrease) behavioral performance. Conclusion: The present review lends novel, experimental support for key predictions from health behavior theories, and demonstrates that interventions that modify attitudes, norms, and self-efficacy are effective in promoting health behavior change

Effect of vitamin D supplementation on blood pressure:a systematic review and meta-analysis incorporating individual patient data

D-PRESSURE Collaboration: et al.[Importance]: Low levels of vitamin D are associated with elevated blood pressure (BP) and future cardiovascular events. Whether vitamin D supplementation reduces BP and which patient characteristics predict a response remain unclear.[Objective]: To systematically review whether supplementation with vitamin D or its analogues reduce BP.[Data Sources]: We searched MEDLINE, CINAHL, EMBASE, Cochrane Central Register of Controlled Trials, and http://www.ClinicalTrials.com augmented by a hand search of references from the included articles and previous reviews. Google was searched for gray literature (ie, material not published in recognized scientific journals). No language restrictions were applied. The search period spanned January 1, 1966, through March 31, 2014.[Study Selection]: We included randomized placebo-controlled clinical trials that used vitamin D supplementation for a minimum of 4 weeks for any indication and reported BP data. Studies were included if they used active or inactive forms of vitamin D or vitamin D analogues. Cointerventions were permitted if identical in all treatment arms.[Data Extraction and Synthesis]: We extracted data on baseline demographics, 25-hydroxyvitamin D levels, systolic and diastolic BP (SBP and DBP), and change in BP from baseline to the final follow-up. Individual patient data on age, sex, medication use, diabetes mellitus, baseline and follow-up BP, and 25-hydroxyvitamin D levels were requested from the authors of the included studies. For trial-level data, between-group differences in BP change were combined in a random-effects model. For individual patient data, between-group differences in BP at the final follow up, adjusted for baseline BP, were calculated before combining in a random-effects model.[Main Outcomes and Measures]: Difference in SBP and DBP measured in an office setting.[Results]: We included 46 trials (4541 participants) in the trial-level meta-analysis. Individual patient data were obtained for 27 trials (3092 participants). At the trial level, no effect of vitamin D supplementation was seen on SBP (effect size, 0.0 [95% CI, −0.8 to 0.8] mm Hg; P = .97; I2 = 21%) or DBP (effect size, −0.1 [95% CI, −0.6 to 0.5] mm Hg; P = .84; I2 = 20%). Similar results were found analyzing individual patient data for SBP (effect size, −0.5 [95% CI, −1.3 to 0.4] mm Hg; P = .27; I2 = 0%) and DBP (effect size, 0.2 [95% CI, −0.3 to 0.7] mm Hg; P = .38; I2 = 0%). Subgroup analysis did not reveal any baseline factor predictive of a better response to therapy.[Conclusions and Relevance]: Vitamin D supplementation is ineffective as an agent for lowering BP and thus should not be used as an antihypertensive agent.Peer reviewe