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Double diffusion refers to a variety of turbulent processes in which potential energy is released into kinetic energy, made possible in the ocean by the difference in molecular diffusivities between salinity and temperature. Here, we present a new method for estimating the kinetic energy dissipation rates forced by double‐diffusive convection using temperature and salinity data alone. The method estimates the up‐gradient diapycnal buoyancy flux associated with double diffusion, which is hypothesized to balance the dissipation rate. To calculate the temperature and salinity gradients on small scales we apply a canonical scaling for compensated thermohaline variance (or 'spice') on sub‐measurement scales with a fixed buoyancy gradient. Our predicted dissipation rates compare favorably with microstructure measurements collected in the Chukchi Sea. Fine et al. (2018), https://doi.org/10.1175/jpo-d-18-0028.1, showed that dissipation rates provide good estimates for heat fluxes in this region. Finally, we show the method maintains predictive skill when applied to a sub‐sampling of the Conductivity, Temperature, Depth (CTD) data. Plain Language Summary: Understanding the transport of heat in the Arctic Ocean is vital for predicting the fate of sea‐ice in the decades to come. Small‐scale turbulence is an important driver of heat transport and one of the major forms of this turbulence is known as 'double‐diffusive convection'. This is where gradients in temperature and salinity drive turbulence. It is only possible because salinity diffuses significantly slower than temperature, hence the name 'double‐diffusive'. The most direct measurements of ocean mixing require sampling velocity or temperature gradients on scales <1 mm, so‐called microstructure measurements. Here we present a new method for estimating the energy dissipated by double‐diffusive convection using temperature and salinity measurements on larger scales (100s–1000s of metres). We apply the method to a high‐resolution survey of temperature and salinity through a subsurface Arctic eddy and compare the results with simultaneous microstructure measurements. The new technique can reproduce up to 72% of the observed dissipation rates to within the measurement uncertainty. This suggests the method could be used to estimate the dissipation and so heat fluxes associated with double‐diffusive convection in regions without microstructure measurements. The method also performs well when applied to data sub‐sampled on larger scales. Key Points: We develop a method for estimating dissipation rates due to double‐diffusive convection from temperature and salinity data using an energetic argumentThe method reproduces the patterns and magnitude of dissipation rates and heat fluxes from microstructure measurements across an arctic eddyThe technique performs well even when applied to lower resolution Conductivity, Temperature, Depth (CTD) data [ABSTRACT FROM AUTHOR]

Objectives: To review studies that used direct observation (i.e., videotaping or audiotaping) methods in palliative/end-of-life care communication research. Design: Descriptive thematic analysis. Setting: Multinational studies were conducted in both the outpatient and inpatient setting. Measurements: Extensive bibliographic searches (January 1, 1998 to July 31, 2009) of English-language literature involving physician-patient (or physician-family) interactions were conducted and augmented by reviews of reference listings. Three investigators independently abstracted key information from each article. Results: Of the 20 retained articles, most enrolled young-old participants (mean age, 60 years) who were white and had a cancer diagnosis. Patient/family participation rates ranged from 68% to 89% demonstrating feasibility of this approach when studying palliative/end-of-life care communication issues. Four common themes were identified: (1) physicians focus on medical/technical and avoid emotional/quality of life issues; (2) sensitive topics are perceived by physicians to take longer to discuss and often do take longer to discuss; (3) physicians dominate discussions; and (4) patient/family satisfaction is associated with supportive physician behaviors. Conclusions: This study demonstrates that direct observation methods can be feasibly used when studying physician-patient/physician-family communication in palliative/end-of-life care, but few investigations have utilized this approach. This article highlights areas that need improvement, including physicians' ability to address patient/family emotional issues and provide what patients and families find most satisfying (participation and support). A particular focus on older patients and patients with end-stage or late-stage chronic (noncancer) illness, the adaptation/application of existing communication measurement tools to capture palliative care communication issues, and development of corresponding outcome measures to assess impact is now needed. [ABSTRACT FROM AUTHOR]

Cladopsammia gracilis (Dendrophylliidae), an ahermatypic coral inhabits the northern Red Sea. Two color morphs (pink and orange) are found aggregated in caves devoid of hermatypic corals, associated with crustose coralline algae (CCA). Sequencing the rDNA ITS region revealed a separate clustering of members of each color morph. Both morphs grow in shallow waters, with orange corals limited to the upper 4 m, while some pink coral aggregates thrive deeper than 30 m. Planulae were released between June and December. Pink planulae treated with antibiotics and exposed at different intervals to CCA, were competent and metamorphosed even 110 days after release. Maximal competency period for orange planulae was 70 days. All planulae were enhanced to metamorphose in presence of CCA. The mean age at metamorphosis of pink and orange planulae treated with CCA differed significantly. Most orange planulae settled directly on the CCA while most pink planulae settled on the wall of the experiment vial. The morphs differed significantly in the calyx cross-section area of primary polyps. Despite being considered a single species according to skeletal based taxonomy, the significant ecological and molecular differences between pink and orange C. gracilis specimens suggest that they may belong to separate species. [ABSTRACT FROM AUTHOR]

The sponge Tetilla sp. (Tetractinomorpha: Tetillidae) is a common species in the eastern Mediterranean. This sponge inhabits four different habitat types differing in wave impact and irradiance levels. Two of these habitats (a shallow cave and deep water) are characterized by relatively calm water, whereas the other two (shallow exposed site and tide pools) are in turbulent water with high energy flow. The present study examined the influence of physical (depth, illumination and water motion) and biotic factors on morphology, skeletal plasticity and reproductive traits among the four spatially separated populations. Sponges from tidal pools had significantly larger body volume than sponges from deep water and from shallow caves (ANOVA: tidal-deep P<0.0001; tidal-shallow caves P<0.05). Sponges from exposed habitats were significantly larger than deep-water sponges (ANOVA: P=0.01). In addition, individuals from tide pools and from the exposed habitat had a significantly higher proportion of structural silica than sponges from the calmer deep water and from the cave sites. Oxea spicules in sponges from the calm habitats were significantly shorter than in those from the tidal pools and the exposed habitats. The percentage of spicules out of a sponge’s dry weight in individuals transplanted from deep (calm) to shallow (turbulent) water significantly increased by 21.9±12.9%. The new spicule percentage did not differ significantly from that of sponges originally from shallow water. Oocyte diameter differed significantly between habitats. The maximal size of mature eggs was found in deep-water sponges in June (97±5 μm). In the shallow habitats, a smaller maximal oocyte diameter was found in the cave, in May (56.5±3 μm). Furthermore, oocyte density in shallow-water sponges was highest in May and decreased in June (with 88.2±9 and 19.3±9 oocytes mm−2, respectively). At the same time (June), oocyte density of deep-water sponges had just reached its maximum (155±33.7 oocytes mm−2). The difference in oocyte size and density between deep- and shallow-water individuals indicates an earlier gamete release in the shallow sponge population. The results suggest that plasticity in skeletal design of this sponge indicates a trade off between spicule production and investment in reproduction. [ABSTRACT FROM AUTHOR]

Deals with a study which synthesized a biomaterial whose surface inhibits non-specific protein and cell attachment. Materials and methods; Results and discussion; Conclusion.

Six weeks after varicose vein surgery, a patient presented with an intensely irritating, florid, purple, papular rash. This matched the line of long saphenous vein stripping and avulsions perfectly. A diagnosis of lichen planus was made by a consultant dermatologist and confirmed histologically by biopsy. Treatment with topical corticosteroids resulted in a dramatic improvement and the rash healed to leave pigmentation. [ABSTRACT FROM AUTHOR]

We propose a system for observing the correlated phase dynamics of two mesoscopic ensembles of atoms through their collective coupling to an optical cavity. We find a dynamical quantum phase transition induced by pump noise and cavity output coupling. The spectral properties of the superradiant light emitted from the cavity show that at a critical pump rate the system undergoes a transition from the behavior of two independent oscillators to the phase locking that is the signature of quantum synchronization. [ABSTRACT FROM AUTHOR]

Abstract: Postoperative myocardial ischaemia is the leading cause of life expectancy impairment after high cardiac risk surgical procedures. Preoperative identification of patients at high risk for such complication helps reducing its postoperative incidence through therapeutic adjustments. The former relies upon preoperative selection of patients who are candidates for cardiac testing using dobutamine stress echocardiography, according to ACC/AHA guidelines. This exam evaluates echographic myocardial response to a pharmacological stress induced by dobutamine infusion. Its aim is to reproduce part of the stress the myocardium will undergo during surgical procedure. A stress induced myocardial ischaemia suggests such a complication could occur postoperatively. A positive dobutamine stress echocardiography justifies to prescribe preoperative anti-ischaemic treatment in order to reduce the cardiac risk of the further surgical procedure. Moreover, it justifies clear definition of perioperative haemodynamic objectives. Whatever the result of the dobutamine stress echocardiography, cardiac ischaemia should be monitored up to the third postoperative day on the basis of a daily 12-lead electrocardiogram recording and daily plasmatic troponin Ic measurement. [Copyright &y& Elsevier]

Objectives: In the present study, we describe the characteristics and examine the anticoagulation levels and safety of subcutaneous enoxaparin in unstable angina (UA)/non-ST-segment elevation myocardial infarction (NSTEMI) patients who would not have been eligible in the Efficacy Safety Subcutaneous Enoxaparin in Non-Q-wave Coronary Events (ESSENCE) and Thrombolysis In Myocardial Infarction (TIMI)-11B trials.Background: It is not known whether the benefit shown with enoxaparin in the selected population of pivotal trials can be extended to the real world.Methods: In our center, all patients with UA/NSTEMI are anticoagulated with subcutaneous enoxaparin adjusted to creatinine clearance. Among 515 consecutive patients, we identified 174 who would not have been eligible for ESSENCE or TIMI-11B ("EP" group for excluded patients). We evaluated cardiovascular death or non-fatal myocardial infarction (MI), as well as major and minor bleeding events, at 30 days in the EP group and in patients without any of the exclusion criteria ("NEP" group for non-excluded patients).Results: This EP group was older, had a higher female/male ratio, and more frequently had a history of MI or a diagnosis of non-Q MI on admission than the NEP group. The distribution of the anti-Xa activity was similar in both groups. The bleeding rates (major and minor) at 30 days were similar in the EP and NEP groups (2.3% vs. 2.9%, respectively, P = NS). On multivariate analysis, the use of glycoprotein IIb/IIIa inhibitors and the presence of hypertension were the only independent predictors of bleeding found in the whole population. Compared with the NEP group, the EP group had a fourfold increased rate of death or MI at 30 days (15.5% vs. 4.1%, p < 0.01). On multivariate analysis, the independent predictors of death or MI at 30 days were NSTEMI on admission, creatinine clearance, and heart failure.Conclusions: Patients who do not fit the enrollment criteria of ESSENCE/TIMI-11B have higher risk baseline characteristics for both bleeding and ischemic events. In these patients, enoxaparin with dose adjustment to creatinine clearance provides adequate anti-Xa levels and no excess of bleeding. [ABSTRACT FROM AUTHOR]

Congenital malformations, including neural tube defects (NTDs), are significantly increased in the offspring of diabetic mothers. We previously reported that in the embryos of a mouse model of diabetic pregnancy, NTDs are associated with reduced expression of the gene Pax-3, which encodes a transcription factor that regulates neural tube development, and that reduced expression of Pax-3 leads to neuroepithelial apoptosis. In this study, we used three approaches to test whether glucose alone could be responsible for these adverse effects of diabetes on embryonic development. First, primary culture of embryo tissue in medium containing 15 mmol/l glucose inhibited Pax-3 expression compared with culture in medium containing 5 mmol/l glucose. Second, inducing hyperglycemia in pregnant mice by subcutaneous glucose administration significantly inhibited Pax-3 expression (P < 0.05), as demonstrated by quantitative reverse transcription-polymerase chain reaction assay of Pax-3 mRNA, and also increased neural tube apoptosis (P < 0.05). NTDs were significantly increased in glucose-injected pregnancies when blood glucose levels were >250 mg/dl (P < 0.002) but not in moderately hyperglycemic pregnancies (150-250 mg/dl, P = 0.37). Third, phlorizin administration to pregnant diabetic mice reduced blood glucose levels and the rate of NTDs. As seen with glucose-injected pregnancies, the rate of NTDs in phlorizin-treated diabetic pregnancies was related to the severity of hyperglycemia, since NTDs were significantly increased in severely hyperglycemic (>250 mg/dl) diabetic pregnancies (P < 0.001) but not in moderately hyperglycemic pregnancies (150-250 mg/dl, P = 0.35). These two findings, that elevated glucose alone can cause the changes in Pax-3 expression observed during diabetic pregnancy and that the NTD rate rises with significant increases in blood glucose levels, suggest that congenital malformations associated with diabetic pregnancy are caused by disruption of regulatory gene expression in the embryo in response to elevated glucose. [ABSTRACT FROM AUTHOR]

Presents a letter to the editor in the April 7, 1989 issue of the 'Journal of the American Medical Association,' noting the risk of injury associated with the use of personal watercraft or personal water vehicles.