Comment on "Novel Convective Instabilities in a Magnetic Fluid"

Comment on the paper "Novel Convective Instabilities in a Magnetic Fluid" by W. Luo, T. Du, and J. Huang, Phys. Rev. Lett., v.82, p.4134 (1999).Comment: 1 page, 1 figure, To appear in Phys. Rev. Lett. (2001

Reconstruction of eolian bed forms and paleocurrents from cross-bedded strata at Victoria Crater, Meridiani Planum, Mars

Outcrop exposures imaged by the Opportunity rover at Victoria Crater, a 750 m diameter crater in Meridiani Planum, are used to delineate sedimentary structures and further develop a dune-interdune depositional model for the region. The stratigraphy at Victoria Crater, observed during Opportunity's partial traverse of its rim, includes the best examples of meter-scale eolian cross bedding observed on Mars to date. The Cape St. Mary promontory, located at the southern end of the rim traverse, is characterized by meter-scale sets of trough cross bedding, suggesting northward migrating sinuous-crested bed forms. Cape St. Vincent, which is located at the opposite end of the traverse, shows tabular-planar stratification indicative of climbing bed forms with meter- to decameter-scale dune heights migrating southward. Promontories located between Cape St. Mary and Cape St. Vincent contain superposed stratigraphic units with northward and southward dipping beds separated by outcrop-scale bounding surfaces. These bounding surfaces are interpreted to be either reactivation and/or superposition surfaces in a complex erg sea. Any depositional model used to explain the bedding must conform to reversing northward and southward paleomigration directions and include multiple scales of bed forms. In addition to stratified outcrop, a bright diagenetic band is observed to overprint bedding and to lie on an equipotential parallel to the preimpact surface. Meter-scale cross bedding at Victoria Crater is similar to terrestrial eolian deposits and is interpreted as a dry dune field, comparable to Jurassic age eolian deposits in the western United States

Biobehavioral Indices of Emotion Regulation Relate to School Attitudes, Motivation, and Behavior Problems in a Low-Income Preschool Sample

Effective emotion regulation may promote resilience and preschool classroom adjustment by supporting adaptive peer interactions and engagement in learning activities. We investigated how hypothalamus-pituitary-adrenal axis (HPA) regulation, cardiac reactivity, and classroom emotion displays related to adjustment among low-income preschoolers attending Head Start. A total of 62 four-year-olds completed a laboratory session including a baseline soothing video; emotion-eliciting slides/video clips, and recovery. Salivary cortisol, heart rate, and vagal tone were measured throughout. Independent coders used handheld computers to observe classroom emotion expression/regulation. Teachers rated child motivation, persistence/attention, learning attitudes, and internalizing/externalizing symptoms. Results reveal associations between biobehavioral markers of regulatory capacity and early school adjustment.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73847/1/annals.1376.043.pd

Hepatosplenic Gamma/Delta T-Cell Lymphoma Masquerading as Alcoholic Hepatitis and Methadone Withdrawal

Hepatosplenic gamma/delta T-cell lymphoma is a rare neoplasm of mature gamma/delta T-cells with sinusoidal infiltration of spleen, liver, and bone marrow. Patients are predominantly adolescent and young adult males and usually present with marked hepatosplenomegaly. Pancytopenia is another common finding. Despite an initial response to treatment, patients have a median survival of one to two years. In this report, we document a case of alcoholic hepatitis and methadone withdrawal masquerading unsuspected, hepatosplenic gamma/delta T-cell lymphoma with unusual CD20 positivity

Prognostic implications of left ventricular global longitudinal strain in heart failure patients with narrow QRS complex treated with cardiac resynchronization therapy: a subanalysis of the randomized EchoCRT trial

Aim: Left ventricular (LV) global longitudinal strain (GLS) reflects LV systolic function and correlates inversely with the extent of LV myocardial scar and fibrosis. The present subanalysis of the Echocardiography Guided CRT trial investigated the prognostic value of LV GLS in patients with narrow QRS complex. Methods and results: Left ventricular (LV) global longitudinal strain (GLS) was measured on the apical 2-, 4- and 3-chamber views using speckle tracking analysis. Measurement of baseline LV GLS was feasible in 755 patients (374 with cardiac resynchronization therapy (CRT)-ON and 381 with CRT-OFF). The median value of LV GLS in the overall population was 7.9%, interquartile range 6.2–10.1%. After a mean follow-up period of 19.4 months, 95 patients in the CRT-OFF group and 111 in the CRT-ON group reached the combined primary endpoint of all-cause mortality and heart failure hospitalization. Each 1% absolute unit decrease in LV GLS was independently associated with 11% increase in the risk to reach the primary endpoint (Hazard ratio 1.11; 95% confidence interval 95% 1.04–1.17, P < 0.001), after adjusting for ischaemic cardiomyopathy and randomization treatment among other clinically relevant variables. When categorizing patients according to quartiles of LV GLS, the primary endpoint occurred more frequently in patients in the lowest quartile (<6.2%) treated with CRT-ON vs. CRT-OFF (45.6% vs. 28.7%, P = 0.009) whereas, no differences were observed in patients with LV GLS ≥6.2% treated with CRT-OFF vs. CRT-ON (23.7% vs. 24.5%, respectively; P  = 0.62). Conclusion: Low LV GLS is associated with poor outcome in heart failure patients with QRS width <130 ms, independent of randomization to CRT or not. Importantly, in the group of patients with the lowest LV GLS quartile, CRT may have a detrimental effect on clinical outcomes

The sensory feedback mechanisms enabling couples to walk synchronously: An initial investigation

The inattentive eye often will not notice it, but synchronization among human walking partners is quite common. In this first investigation of this phenomenon, we studied its frequency and the mechanisms that contribute to this form of "entrainment." Specifically, by modifying the available communication links between two walking partners, we isolated the feedback mechanisms that enable couples to synchronize their stepping pattern when they walk side-by-side. Although subjects were unaware of the research aims and were not specifically asked to walk in synchrony, we observed synchronized walking in almost 50% of the walking trials, among couples who do not usually walk together. The strongest in-phase synchrony occurred in the presence of tactile feedback (i.e., handholding), perhaps because of lower and upper extremity coupling driven in part by arm swing. Interestingly, however, even in the absence of visual or auditory communication, couples also frequently walked in synchrony while 180 degrees out-of-phase, likely using different feedback mechanisms. These findings may partially explain how patients with certain gait disorders and disturbed rhythm enhance their gait when they walk with a partner and suggest alternative interventions that might improve the stepping pattern. Further, this preliminary investigation highlights the relatively ubiquitous nature of an interesting phenomenon that has not previously been studied and suggests that further work is needed to better understand the mechanisms that entrain the gait of two walking partners and allows couples to walk in synchrony with minimal or no conscious effort