High Electrochemical Performance Silicon Thin-Film Free-Standing Electrodes Based on Buckypaper for Flexible Lithium-Ion Batteries

Recently, applications for lithium-ion batteries (LIBs) have expanded to include electric vehicles and electric energy storage systems, extending beyond power sources for portable electronic devices. The power sources of these flexible electronic devices require the creation of thin, light, and flexible power supply devices such as flexile electrolytes/insulators, electrode materials, current collectors, and batteries that play an important role in packaging. Demand will require the progress of modern electrode materials with high capacity, rate capability, cycle stability, electrical conductivity, and mechanical flexibility for the time to come. The integration of high electrical conductivity and flexible buckypaper (oxidized Multi-walled carbon nanotubes (MWCNTs) film) and high theoretical capacity silicon materials are effective for obtaining superior high-energy-density and flexible electrode materials. Therefore, this study focuses on improving the high-capacity, capability-cycling stability of the thin-film Si buckypaper free-standing electrodes for lightweight and flexible energy-supply devices. First, buckypaper (oxidized MWCNTs) was prepared by assembling a free stand-alone electrode, and electrical conductivity tests confirmed that the buckypaper has sufficient electrical conductivity (10⁻⁴(S m⁻¹) in LIBs) to operate simultaneously with a current collector. Subsequently, silicon was deposited on the buckypaper via magnetron sputtering. Next, the thin-film Si buckypaper freestanding electrodes were heat-treated at 600 °C in a vacuum, which improved their electrochemical performance significantly. Electrochemical results demonstrated that the electrode capacity can be increased by 27/26 and 95/93 μAh in unheated and heated buckypaper current collectors, respectively. The measured discharge/charge capacities of the USi_HBP electrode were 108/106 μAh after 100 cycles, corresponding to a Coulombic efficiency of 98.1%, whereas the HSi_HBP electrode indicated a discharge/charge capacity of 193/192 μAh at the 100th cycle, corresponding to a capacity retention of 99.5%. In particular, the HSi_HBP electrode can decrease the capacity by less than 1.5% compared with the value of the first cycle after 100 cycles, demonstrating excellent electrochemical stability.     

Effect of vancomycin loading dose on clinical outcome in critically ill patients with methicillin-resistant Staphylococcus aureus pneumonia

BackgroundVancomycin is the treatment of choice for serious methicillin-resistant Staphylococcus aureus (MRSA) infections. Current guidelines recommend giving an initial loading dose (LD) of 25–30 mg/kg to rapidly increase the serum concentration. However, high-quality evidence for the clinical benefit of LD is lacking. Herein, we aim to examine the association between vancomycin LD and clinical outcome.MethodsA retrospective cohort study was conducted on adult patients treated for MRSA pneumonia with vancomycin in medical intensive care units from April 2016 to August 2018. MRSA pneumonia was defined by the Centers for Disease Control and National Healthcare Safety Network definition. The primary outcome was the clinical cure of pneumonia. Secondary outcome measures included time to pharmacokinetic (PK) target attainment, microbiological cure, acute kidney injury, and all-cause mortality.ResultsA total of 81 patients were included; of these 22 (27.2%) received LD. The mean initial dose was significantly higher in the LD group. Clinical cure was similar in both groups (68.2% vs. 66.1% in the LD and non-LD groups, respectively; P=0.860). No significant difference was observed in the microbiological cure, all-cause mortality, and incidence of acute kidney injury. Furthermore, no difference was observed in terms of time to PK target attainment (69.2 vs. 63.4 h in the LD and non-LD groups, respectively; P=0.624). Vancomycin minimum inhibitory concentration of <2 mg/L was identified as an independent predictive factor for clinical cure in multivariable analysis, whereas vancomycin LD was not.ConclusionsInitial LD is not associated with better clinical outcome or rapid pharmacological target attainment in critically ill patients with MRSA pneumonia. Further studies are warranted to provide better evidence for this widely recommended practice.     

The tertiary structure and domain organization of coagulation factor VIII

Factor VIII (fVIII) is a serum protein in the coagulation cascade that nucleates the assembly of a membrane-bound protease complex on the surface of activated platelets at the site of a vascular injury. Hemophilia A is caused by a variety of mutations in the factor VIII gene and typically requires replacement therapy with purified protein. We have determined the structure of a fully active, recombinant form of factor VIII (r-fVIII), which consists of a heterodimer of peptides, respectively containing the A1-A2 and A3-C1-C2 domains. The structure permits unambiguous modeling of the relative orientations of the 5 domains of r-fVIII. Comparison of the structures of fVIII, fV, and ceruloplasmin indicates that the location of bound metal ions and of glycosylation, both of which are critical for domain stabilization and association, overlap at some positions but have diverged at others.     

Venous dynamics in leg lymphedema

To determine whether there is anatomical and/or functional impairment to venous return in patients with lymphedema, we examined venous dynamics in 41 patients with unilateral leg lymphedema. A Volometer was used for computer analysis of leg volume, a color Duplex Doppler scanner was used to determine deep vein patency and skin thickness, and Air-plethysmography was used to assess ambulatory venous pressure, venous volume, venous filling index and the ejection fraction. In the lymphedematous leg, volume and skin thickness were uniformly increased (126.4 +/- 21.3% and 156.9 +/- 44.5%) (mean +/- S.D.), respectively. The ambulatory venous pressure was also increased (134 +/- 60.7%) as was the venous volume (124.5 +/- 37.5%), and the venous filling index (134.5 +/- 50.5%). The ejection fraction was decreased (94.9 +/- 26.1%). Greater leg volume correlated with increased venous volume and venous filling index (values = 0.327, 0.241, respectively) and decreased ejection fraction (r = -0.133). Increased subcutaneous thickness correlated with increased venous filling index and venous volume (r = 0.307, 0.126, respectively) and decreased ejection fraction (r = -0.202). These findings suggest that soft tissue edema from lymphatic stasis gradually impedes venous return which in turn aggravates the underlying lymphedema.     

Oncogenic osteomalacia associated with mesenchymal tumour detected by indium-111 octreotide scintigraphy

In a 40-year-old man who had suffered from vague and generalized bone pains for 7 years due to oncogenic osteomalacia, the causative tumour was finally detected by Indium-111 octreotide scintigraphy. Some characteristics of the tumour associated with oncogenic osteomalacia, such as its size, growth rate, location and origin, often make the diagnosis difficult. However, the recent discovery of somatostatin receptors in mesenchymal tumours, which are the most common cause of oncogenic osteomalacia, has raised the possibility of early detection of this devastating disorder. Here, we report that radiolabelled octreotide scintigraphy has a potential role as a diagnostic tool in oncogenic osteomalacia. However, the exact role of somatostatin receptors in tumours associated with oncogenic osteomalacia still remains elusive.     

Outcomes of gynecologic oncology patients undergoing robotic-assisted laparoscopic procedures in a university setting

This study evaluated intraoperative complications and postoperative outcomes of gynecologic oncology patients undergoing robotic-assisted (RA) laparoscopic procedures in a university setting. A retrospective chart review evaluated all gynecologic oncology patients at the University of Alabama at Birmingham who underwent attempted RA procedures between August 2006 and October 2011. Patient demographics, medical/surgical history, intraoperative complications, postoperative outcomes, conversion rates, readmission rates, and length of stay were examined. Total complication rates were assessed over time for each surgeon. 681 patients underwent planned RA procedures by seven gynecologic oncologists. The mean body mass index was 33.5 kg/m² (range 16.6–71.0 kg/m²). 61.4 % were diagnosed with malignancy. The most common procedure was RA hysterectomy with unilateral/bilateral salpingo-oophorectomy (37.2 %). Robotic staging was performed in 291 patients (45.1 %). Mean estimated blood loss was 75 ml (range 5–700 ml). 36 patients (5.3 %) were converted to laparotomy. The most common reason for conversion was adhesions (30.1 %), followed by uterine size (22.2 %). In 107 cases, a surgical modification was required for specimen removal including mini-laparotomy (24), extension of accessory port (36), morcellation (9), and difficult vaginal delivery (38). 3.7 % had intraoperative complications; 6 patients had a cystotomy and 5 had a vascular injury. Postoperatively, 20 patients had a febrile episode, 9 had wound complications, and 3 had a vaginal cuff dehiscence. 27 (4.2 %) patients were readmitted within 30 days. Complication rates and conversion rates were similar per surgeon. Total complication rates for evaluable surgeons were similar between the first 10 cases and subsequent 50 cases. Although patients undergoing RA procedures in a university setting are high risk, the conversion rate to laparotomy is low and intraoperative and postoperative complications are acceptable. Total complication rates for each surgeon were not impacted by the number of cases performed.     

Carvacrol effectively protects demyelination by suppressing transient receptor potential melastatin 7 (TRPM7) in Schwann cells

Anatomical Science International - Peripheral neurodegenerative processes are essential for regenerating damaged peripheral nerves mechanically or genetically. Abnormal neurodegenerative processes...