Snap evaporation of droplets on smooth topographies

Droplet evaporation on solid surfaces is important in many applications including printing, micro-patterning and cooling. While seemingly simple, the configuration of evaporating droplets on solids is difficult to predict and control. This is because evaporation typically proceeds as a “stick-slip” sequence—a combination of pinning and de-pinning events dominated by static friction or “pinning”, caused by microscopic surface roughness. Here we show how smooth, pinning-free, solid surfaces of non-planar topography promote a different process called snap evaporation. During snap evaporation a droplet follows a reproducible sequence of configurations, consisting of a quasi-static phase-change controlled by mass diffusion interrupted by out-of-equilibrium snaps. Snaps are triggered by bifurcations of the equilibrium droplet shape mediated by the underlying non-planar solid. Because the evolution of droplets during snap evaporation is controlled by a smooth topography, and not by surface roughness, our ideas can inspire programmable surfaces that manage liquids in heat- and mass-transfer applications

Equivalence classes of the second order ODEs with the constant Cartan invariant

Second order ordinary differential equations that possesses the constant invariant are investigated. Four basic types of these equations were found. For every type the complete list of nonequivalent equations is issued. As the exampes the equivalence problem for the Painleve II equation, Painleve III equation with three zero parameters, Emden equations and for some other equations is solved

Early High-Dose Vitamin D3 for Critically Ill, Vitamin D-Deficient Patients

BACKGROUND: Vitamin D deficiency is a common, potentially reversible contributor to morbidity and mortality among critically ill patients. The potential benefits of vitamin D supplementation in acute critical illness require further study. METHODS: We conducted a randomized, double-blind, placebo-controlled, phase 3 trial of early vitamin D3 supplementation in critically ill, vitamin D-deficient patients who were at high risk for death. Randomization occurred within 12 hours after the decision to admit the patient to an intensive care unit. Eligible patients received a single enteral dose of 540,000 IU of vitamin D3 or matched placebo. The primary end point was 90-day all-cause, all-location mortality. RESULTS: A total of 1360 patients were found to be vitamin D-deficient during point-of-care screening and underwent randomization. Of these patients, 1078 had baseline vitamin D deficiency (25-hydroxyvitamin D level,[50 nmol per liter]) confirmed by subsequent testing and were included in the primary analysis population. The mean day 3 level of 25-hydroxyvitamin D was 46.9±23.2 ng per milliliter (117±58 nmol per liter) in the vitamin D group and 11.4±5.6 ng per milliliter (28±14 nmol per liter) in the placebo group (difference, 35.5 ng per milliliter; 95% confidence interval [CI], 31.5 to 39.6). The 90-day mortality was 23.5% in the vitamin D group (125 of 531 patients) and 20.6% in the placebo group (109 of 528 patients) (difference, 2.9 percentage points; 95% CI, -2.1 to 7.9; P = 0.26). There were no clinically important differences between the groups with respect to secondary clinical, physiological, or safety end points. The severity of vitamin D deficiency at baseline did not affect the association between the treatment assignment and mortality. CONCLUSIONS: Early administration of high-dose enteral vitamin D3 did not provide an advantage over placebo with respect to 90-day mortality or other, nonfatal outcomes among critically ill, vitamin D-deficient patients. METHODS: We conducted a randomized, double-blind, placebo-controlled, phase 3 trial of early vitamin D3 supplementation in critically ill, vitamin D-deficient patients who were at high risk for death. Randomization occurred within 12 hours after the decision to admit the patient to an intensive care unit. Eligible patients received a single enteral dose of 540,000 IU of vitamin D3 or matched placebo. The primary end point was 90-day all-cause, all-location mortality

Current CONtrolled Transmit And Receive Coil Elements (C2ONTAR) for Parallel Acquisition and Parallel Excitation Techniques at High-Field MRI

A novel intrinsically decoupled transmit and receive radio-frequency coil element is presented for applications in parallel imaging and parallel excitation techniques in high-field magnetic resonance imaging. Decoupling is achieved by a twofold strategy: during transmission elements are driven by current sources, while during signal reception resonant elements are switched to a high input impedance preamplifier. To avoid B0 distortions by magnetic impurities or DC currents a resonant transmission line is used to relocate electronic components from the vicinity of the imaged object. The performance of a four-element array for 3 T magnetic resonance tomograph is analyzed by means of simulation, measurements of electromagnetic fields and bench experiments. The feasibility of parallel acquisition and parallel excitation is demonstrated and compared to that of a conventional power source-driven array of equivalent geometry. Due to their intrinsic decoupling the current-controlled elements are ideal basic building blocks for multi-element transmit and receive arrays of flexible geometry

The septic milieu triggers expression of spliced tissue factor mRNA in human platelets: Sepsis induces platelet tissue factor mRNA

Activated platelets have previously-unrecognized mechanisms of post-transcriptional gene expression that may influence hemostasis and inflammation. A novel pathway involves splicing of pre-mRNAs in resting platelets to mature, translatable mRNAs in response to cellular activation

Hydrodynamics of the VanA-type VanS histidine kinase: an extended solution conformation and first evidence for interactions with vancomycin

VanA-type resistance to glycopeptide antibiotics in clinical enterococci is regulated by the VanSARA two-component signal transduction system. The nature of the molecular ligand that is recognised by the VanSA sensory component has not hitherto been identified. Here we employ purified, intact and active VanSA membrane protein (henceforth referred to as VanS) in analytical ultracentrifugation experiments to study VanS oligomeric state and conformation in the absence and presence of vancomycin. A combination of sedimentation velocity and sedimentation equilibrium in the analytical ultracentrifuge (SEDFIT, SEDFIT-MSTAR and MULTISIG analysis) showed that VanS in the absence of the ligand is almost entirely monomeric (molar mass M = 45.7 kDa) in dilute aqueous solution with a trace amount of high molar mass material (M ~ 200 kDa). The sedimentation coefficient s suggests the monomer adopts an extended conformation in aqueous solution with an equivalent aspect ratio of ~ (12+2). In the presence of vancomycin over a 33% increase in the sedimentation coefficient is observed with the appearance of additional higher s components, demonstrating an interaction, an observation consistent with our circular dichroism measurements. The two possible causes of this increase in s – either a ligand induced dimerization and/or compaction of the monomer are considered