Evaporation-induced cavitation in nanofluidic channels

Cavitation, known as the formation of vapor bubbles when liquids are under tension, is of great interest both in condensed matter science as well as in diverse applications such as botany, hydraulic engineering, and medicine. Although widely studied in bulk and microscale-confined liquids, cavitation in the nanoscale is generally believed to be energetically unfavorable and has never been experimentally demonstrated. Here we report evaporation-induced cavitation in water-filled hydrophilic nanochannels under enormous negative pressures up to -7 MPa. As opposed to receding menisci observed in microchannel evaporation, the menisci in nanochannels are pinned at the entrance while vapor bubbles form and expand inside. Evaporation in the channels is found to be aided by advective liquid transport, which leads to an evaporation rate that is an order of magnitude higher than that governed by Fickian vapor diffusion in macro- and microscale evaporation. The vapor bubbles also exhibit unusual motion as well as translational stability and symmetry, which occur because of a balance between two competing mass fluxes driven by thermocapillarity and evaporation. Our studies expand our understanding of cavitation and provide new insights for phase-change phenomena at the nanoscale.     

Lipoprotein(a), interleukin-10, C-reactive protein, and 8-year outcome after percutaneous coronary intervention

Background:

This prospective study investigated the association between preprocedural biomarker levels and incident major adverse cardiac events (MACE) in complex patients undergoing percutaneous coronary intervention (PCI) with sirolimus‐eluting stenting.

Hypothesis:

Lipoprotein(a) (Lp[a]), interleukin‐10 (IL‐10), and high‐sensitivity C‐reactive protein (CRP) have long‐term prognostic value in patients undergoing PCI.

Methods:

Between April 2002 and February 2003, 161 patients were included in the study. Blood was drawn before the procedure, and biomarkers were measured. Patients were followed‐up for MACE (death, nonfatal myocardial infarction, and repeat revascularization). Cox proportional hazard models were used to determine risk of MACE for tertiles of biomarkers. Both 1‐year and long‐term follow‐up (median, 6 years; maximum, 8 years) were evaluated.

Results:

Mean age was 59 years, and 68% were men. During long‐term follow‐up, 72 MACE occurred (overall crude cumulative incidence: 45% [95% confidence interval (CI): 37%‐52%]). Lp(a) was associated with a higher 1‐year risk of MACE, with an adjusted hazard ratio (HR) of 3.1 (95% CI: 1.1‐8.6) for the highest vs the lowest tertile. This association weakened and lost significance with long‐term follow‐up. IL‐10 showed a tendency toward an association with MACE. The 1‐year HR was 2.1 (95% CI: 0.92‐5.0). Long‐term follow‐up rendered a similar result. The association of CRP with MACE did not reach statistical significance at 1‐year follow‐up. However, CRP was associated with long‐term risk of MACE, with an HR of 1.9 (95% CI: 1.0‐3.5).

Conclusions:

In this prospective study, preprocedural Lp(a) level was associated with short‐term prognosis after PCI. The preprocedural CRP level was associated with long‐term prognosis after PCI. Clin. Cardiol. 2012 DOI: 10.1002/clc.21988 The authors have no funding, financial relationships, or conflicts of interest to disclose.     

Thigh-length versus knee-length compression stockings for deep vein thrombosis prophylaxis in the inpatient setting

Deep vein thrombosis may be a complication of extended length hospital stays. Immobilized patients, such as patients in the postoperative period, are at particularly high risk of developing a deep vein thrombosis, which can be associated with high levels of morbidity and mortality. Due to this, prevention of deep vein thrombosis is of great importance in the inpatient setting. Compression stockings have proven to play an important role in prophylaxis and may be used in their knee-length or thigh-length variety. Although randomized trials have studied the efficacy of both varieties in prevention of deep vein thrombosis, selection is often made without regard to evidence. This meta-analysis pools the findings of current studies comparing knee-length and thigh-length compression stockings for deep vein thrombosis prophylaxis. A fixed effects model was used for this study with a two-sided α-error less than 0.05 considered to be statistically significant. When both varieties of compression stockings are compared, thigh-length stockings offer a risk reduction in deep vein thrombosis development when compared with knee-length (odds ratio 1.197, confidence interval 0.983-1.458). This, however, is an insignificant finding. This analysis concludes that current data does not favor either thigh-length or knee-length compression stockings when it comes to prophylaxis of deep vein thrombosis.     

Strategies for Molecular Classification of Asthma Using Bipartite Network Analysis of Cytokine Expression

Asthma is a chronic inflammatory disease of the airways that leads to various degrees of recurrent respiratory symptoms affecting patients globally. Specific subgroups of asthma patients have severe disease leading to increased healthcare costs and socioeconomic burden. Despite the overwhelming prevalence of the asthma, there are limitations in predicting response to therapy and identifying patients who are at increased risk of morbidity. This syndrome presents with common clinical signs and symptoms; however, awareness of subgroups of asthma patients with distinct characteristics has surfaced in recent years. Investigators attempt to describe the phenotypes of asthma to ultimately assist with diagnostic and therapeutic applications. Approaches to asthma phenotyping are multifold; however, it can be partitioned into 2 essential groups, clinical phenotyping and molecular phenotyping. Innovative techniques such as bipartite network analysis and visual analytics introduce a new dimension of data analysis to identify underlying mechanistic pathways.     

Posterior Scrotal Artery Flap to Cover a Groin Defect: A New Technique

Commonly, a groin defect is reconstructed with flaps from ipsilateral thigh or lower abdomen. Here we present a case report of use of a pedicled flap from the posterior scrotum based on posterior scrotal artery to cover a groin defect exposing femoral vessels. Posterior scrotal artery, to best of our knowledge, has not been described in the literature to cover a groin defect.     

Dsteosynthesis with long volar locking plates for meta- physeal-diaphyseal fractures of the distal radius

Objective：Metaphyseal-diaphyseal fractures of the distal radius are a major treatment dilemma and orthopaedic surgeons have to pay due consideration to restoration of anatomy of distal radius together with rotation of the radial shaft and maintenance of radial bow and interosseous space.We performed this study to evaluate the clinic-radiological outcome of metaphyseal-diaphyseal fractures of the distal radius treated with long volar locking plates.Methods：This prospective study involved 27 patients （22 males and 5 females） with metaphyseal-diaphyseal fracture of the distal radius.Their mean age was （30.12±11.48） years （range 19-52 years） and the follow-up was 26.8 months （range 22-34 months）.All patients underwent open reduction and internal fixation with a long volar locking plate.According to AO/OTA classification,there were 7 type A3,13 type C2 and 7 type C3 fractures.Subjective assessment was done based on the disabilities of the arm,shoulder and hand （DASH） questionnaire.Functional evaluation was done by measuring grip strength and range of motion around the wrist and the radiological determinants included radial angle,radial length,volar angle and ulnar variance.The final assessment was done according to Gartland and Werley scoring system.Results：Postoperative radiological parameters were well maintained throughout the trial,and there was significant improvement in the functional parameters from 6 weeks to final follow-up.The average DASH scores improved from 37.5 at 6 weeks to 4.2 at final follow-up.Final assessment using Gartland and Werley scoring system revealed 66.67%（n=l8） excellent and 33.33% （n=9） good results.There was one case of superficial infection which responded to antibiotics and another carpel tunnel syndrome which was managed conservatively.Conclusion：Volar locking plate fixation for metaphyseal-diaphyseal fractures of distal radius is associated with excellent to good functional outcome,early rehabilitation and minimal complications.