Hybrid Membrane Composed of Nickel Diselenide Nanosheets with Carbon Nanotubes for Catalytic Conversion of Polysulfides in Lithium-Sulfur Batteries.

Lithium-sulfur batteries demonstrate enormous energy density are promising forms of energy storage. Unfortunately, the slow redox kinetics and polysulfides shuttle effect are some of the factors that prevent the its development. To address these issues, the hybrid membrane with combination of nickel diselenide nanosheets modified carbon nanotubes (NSN@CNTs) and utilized Li2 S6 catholyte for lithium sulfur battery. The conductive CNTs facilitates fast electronic/ionic transport, while the polarity of NSN as a strong affinity to lithium polysulfides, effectively anchoring them, facilitating the redox conversion of polysulfide species, and effectively diminishing reaction barriers. The cell with NSN@CNTs delivers the first discharge capacity of 1123.8 mAh g-1 and maintains 786.5 mAh g-1 after 300 cycles (0.2 C) at the sulfur loading 5.4 mg. Its rate capability is commendable, enabling it to sustain a capacity of 559.8 mAh g-1 even at a high discharge rate of 2 C. In addition, its initial discharge capacity can remain 8.33 mAh even at 10.8 mg for duration of 100 cycles. This research indicates the potential application of NSN@CNTs hybrid materials in lithium-sulfur batteries.

Transcatheter Closure of Large Coronary-Cameral Fistulas Using the Patent Ductus Arteriosus Occluder or Amplatzer Vascular Plugs.

Transcatheter closure (TCC) has emerged as the first-line treatment for coronary artery fistulas. However, limited data exist regarding the long-term outcomes and technical aspects of this procedure. We aimed to report the long-term outcomes and technical aspects of TCC of large coronary-cameral fistulas (CCFs).All patients with large CCFs who underwent attempted TCC using the patent ductus arteriosus (PDA) occluder or Amplatzer vascular plug (AVP), from June 2002 to December 2017, were retrospectively reviewed. A total of 23 patients with large CCFs underwent attempted TCC using the PDA occluder or AVP. Most CCFs originated from the right coronary artery and drained predominantly into the right heart chamber. Procedural success was achieved in 21 (91.3%) patients. Devices were deployed using the arteriovenous loop in 15, transarterial approach in 4, and arterio-artery loop approach in 2 patients. Procedural complications included coronary spasm in one and side branch occlusion in one patient. Among these 21 patients with successful device implantation, follow-up angiograms or computed tomography angiograms were obtained in 14 (66.7%) patients at a median of 11.0 (range, 9.8-16.3) months. Late complications included thrombosis of residual fistula segment without myocardial infarction (MI) in one, coronary thrombosis resulting in MI in one, and recanalization necessitating re-intervention in one patient. No death and device embolization occurred.TCC of large CCFs using the PDA occluder or AVP is an effective therapy in anatomically suitable candidates, with favorable long-term outcomes. Given that potentially hazardous complications may occur late after the procedure, long-term periodic evaluation is mandatory.

Immobilisation of sulphur on cathodes of lithium-sulphur batteries via B-doped atomic-layer carbon materials.

Developing new host materials for cathodes and exploring their binding mechanisms in lithium-sulphur batteries are crucial issues since the present host materials exhibit low sulphur entrapment properties, thus resulting in the rapid decay of overall performance. In this work, we systematically investigated B-doped atomic-layer carbon materials as the cathode hosts of lithium-sulphur batteries via density functional theory calculations. Based on the analysis of optimised molecular structures, binding energies and surface charge densities, we found that B-doping can help materials suppress the dissolution of sulphides during cycles, further improving the performance of lithium-sulphur batteries. Additionally, we concluded that the internal interactions among multiple Li2Sn-adsorbed structures facilitate the capture of Li2Sn. Furthermore, we found that B-doped graphdiyne is a promising host material since it exhibits a stronger attraction to Li2Sn than other selected materials and an outstanding sulphur loading of ∼70 wt%.

Enhanced Electrochemical Performance of Simple Electrospun Non-Woven Nickel/Carbon Nanofibers as a Functional Interlayer for Lithium-Sulfur Batteries.

Non-woven nickel/carbon nanofibers (NW(Ni/C)NFs) are developed using a facile one-pot electrospinning method as a functional interlayer for rechargeable lithium-sulfur (Li-S) batteries. The functional interlayer of NW(Ni/C)NFs is sandwiched between a sulfur cathode and the separator and acts as a shuttle inhibitor to sulfur and polysulfides. Because of the sandwiched structure and the nickel additive, the Li-S cell shows better performance in terms of capacity utilization and reversibility. When the NW(Ni/C)NFs were calcined at 900 °C with 1 g of nickel salt additive, the discharge capacity of the cells was the best, and the initial discharge capacity was 1062 mAh g-1. With 200 charge-discharge cycles at 1 C, the discharge capacity of the cells remained above 910 mAh g-1, which is about 85.7% of its initial capacity. The improvement to the cells' electrochemical performance is attributed to the 3D architecture of the NW(Ni/C)NFs as a functional interlayer and to the appropriate amount of nickel addition. This provides a good conductive network with structural stability and the migrating polysulfide reduces the "shuttling phenomenon" during the charge-discharge processes.

Electrospun LiFePO4/C Composite Fiber Membrane as a Binder-Free, Self-Standing Cathode for Power Lithium-Ion Battery.

A LiFePO4/C composite fiber membrane was fabricated by the electrospinning method and subsequent thermal treatment. The thermal decomposition process was analyzed by TG/DSC, the morphology, microstructure and composition were studied using SEM, TEM, XRD, Raman, respectively. The results indicated that the prepared LiFePO4/C composite fibers were composed of nanosized LiFePO4 crystals and amorphous carbon coatings, which formed a three dimensional (3D) long-range networks, greatly enhanced the electronic conductivity of LiFePO4 electrode up to 3.59× 10-2 S · cm-2. The 3D LiFePO4/C fiber membrane could be directly used as a binder-free, self-standing cathode for lithium-ion battery, and exhibited an improved capacity and rate performance. The LiFePO4/C composite electrode delivered a discharge capacity of 116 mAh·g-1, 109 mAh·g-1, 103 mAh·g-1, 91 mAh·g-1, 80 mAh·g-1 at 0.1 C, 0.5 C, 1 C, 3 C, 5 C, respectively. And a stable cycling performance was also achieved that the specific capacity could retain 75 mA·g-1 after 500 cycles at 5 C. Therefore, this LiFePO4/C composite fiber membrane was promising to be used as a cathode for power lithium ion battery.

Tunable Synthesis, Characterization and Magnetic Properties of Core­Shell Cu@M (M = Co or Ni) Nanowires.

The ultralong Cu@M (M = Co or Ni) nanowires (NWs) with core­shell structure were fabricated by a simple method by using the prepared Cu NWs as template. The crystal phases of Cu@M (M = Co or Ni) NWs were confirmed by X-ray diffraction (XRD). The morphology and microstructure of NWs were characterized by scanning electro microscopy (SEM) and transmission electro microscopy (TEM). Different diameters of Cu@M (M = Co or Ni) NWs varying from 120 to 550 nm with length about 10 µm were obtained via controlling the amounts of cobalt (nickel) nitrates in the reduction process. The magnetic properties of samples were measured using vibrating sample magnetometer (VSM). Results revealed that Cu NWs has a characteristic of paramagnetism after coating Co or Ni. The coercivity (H(c)) values of Cu@ Ni and Cu@Co NWs were 114.6 and 102.5 Oe, respectively. Possible formation mechanism for Cu@M (M = Co or Ni) NWs was preliminarily proposed.

Effect of Nickel Coated Multi-Walled Carbon Nanotubes on Electrochemical Performance of Lithium-Sulfur Rechargeable Batteries.

Conventional lithium-sulfur batteries suffer from severe capacity fade, which is induced by low electron conductivity and high dissolution of intermediated polysulfides. Recent studies have shown the metal (Pt, Au, Ni) as electrocatalyst of lithium polysulfides and improved the performance for lithium sulfur batteries. In this work, we present the nickel coated multi-walled carbon nanotubes (Ni-MWNTs) as additive materials for elemental sulfur positive electrodes for lithium-sulfur rechargeable batteries. Compared with MWNTs, the obtained Ni-MWNTs/sulfur composite cathode demonstrate a reversible specific capacity approaching 545 mAh after 200 cycles at a rate of 0.5C as well as improved cycling stability and excellent rate capacity. The improved electrochemical performance can be attributed to the fact the MWNTs shows a vital role on polysulfides adsorption and nickel has a catalytic effect on the redox reactions during charge­discharge process. Meanwhile, the Ni-MWNTs is a good electric conductor for sulfur cathode.

Pharyngoesophageal Reconstruction With the Medial Sural Artery Perforator Flap After Total Laryngopharyngectomy: A New Method.

BACKGROUND: The medial sural artery perforator (MSAP) flap has become a popular target in head and neck reconstruction. This flap has many advantages compared with other free flaps but has not yet been used in the reconstruction of circumferential haryngoesophageal defects. METHODS: Reconstruction of pharyngoesophageal circumferential defects using the MSAP flap was performed in 4 patients. The design of the flap was based on the perforators, which were confirmed by endoscopy. The MSAP flap was tubed and anastomosed end to end to the esophagus. The artery was anastomosed to the superior thyroid arteries, whereas the vein was anastomosed to the internal jugular vein. RESULTS: All the flaps survived. All 4 patients gained acceptable speech and swallow function. One patient developed an infection at the donor site, a second developed fistulas, and a third experienced stricture. All complications were successfully treated. CONCLUSIONS: Here, we demonstrated the use of the MSAP flap in reconstruction of circumferential pharyngoesophageal defects. Further application and follow-up studies should be performed.

[Clinical value of ADMA in patients with pulmonary arterial hypertension combination with congenital heart disease].

OBJECTIVE: To study the concentration of the asymmetrical dimethyl-L-arginine (ADMA) in patients with pulmonary arterial hypertension (PAH) commbination with congenital heart disease (CHD) and its clinical value as a biomaker for diagnosis and prognosis.
 Methods: A total of 100 patients with CHD and 25 healthy adult subjects were recruited. CHD patients were divided into three groups: normal pulmonary arterial pressure group (group A, n=25), mild-to-moderate PAH group (group B, n=25), severe PAH group (group C, n=50). Twenty patients in Group C were treated with sildenafil and followed up for 6 months. The clinical data, including echocardiographic measurements, hemodynamic parameters and ADMA levels, for all subjects were collected.
 Results: The ADMA concentrations in patients with CHD-PAH significantly increased compared with that in the CHD patients without PAH or the health controls, and the ADMA concentrations in CHD patients with severe PAH were significantly higher than that in the CHD patients with mild-to-moderate PAH; serum ADMA concentration was correlated with mean pulmonary arterial pressure (mPAP) (r=0.61, P<0.001) and pulmonary vascular resistance (PVR) (r=0.417, P<0.001) in CHD patients; when using AMDA>0.485 µmol/L as criteria for diagnosis of CHD-PAH, the specificity was 82.7% and the sensitivity was 92.0%; the pulmonary arterial pressure significantly decreased after sildenafil therapy for 6 months, same as the ADMA levels.
 Conclusion: Plasma ADMA could be used as a biomarker to identify PAH in patients with CHD and as a prognosic index to reflect the sildenafil treatment effect.

Structural and optical characteristics of the hexagonal ZnO films grown on cubic MgO (001) substrates.

In this Letter, we report on the structural and optical characteristics of ZnO films with a wurtzite structure grown on MgO (001) substrates with cubic structures. The ZnO films were prepared through the molecular beam epitaxy method, and growth orientation transformation from [0001] to [10-10] direction was observed with the change of growth temperature and thickness. The x-ray diffraction pole figures and in situ RHEED patterns demonstrated that the rotational relationship among grains within the ZnO films appeared in a typical two-fold rotation of about 30° for the [0001] growth orientation and four-fold rotation of about 30° or 60° for the [10-10] growth orientation, respectively. Last, we investigated their optical properties through measuring the transmission and photoluminescence spectra of the ZnO films, which showed the bulk-like bandgap feature of the ZnO films in spite of the existing growth orientation transformation.

Association of serum cystatin C levels with myocardial perfusion and cardiac functional recovery in patients with anterior wall ST elevation myocardial infarction treated with primary coronary intervention.

This study sought to investigate the association of baseline serum cystatin C levels with myocardial perfusion and cardiac functional recovery in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI). 108 patients with a first anterior STEMI who underwent PPCI were enrolled. Serum cystatin C was measured by immunoturbidimetric method. Patients were divided into two groups according to the median cystatin C levels on admission: group 1 (≥median, n = 54) and group 2 (

Formation Mechanism of alpha-Fe2O3 Nanotubes via Electrospinning and Their Adsorption Characteristics of BSA and DNA.

The alpha-Fe2O3 nanotubes with diameters of 400-700 nm have been prepared via the sol-gel assisted electrospinning and subsequent one-step heat treatment with ferric nitrate, ethanol and poly(vinyl pyrrolidone) as starting regents. The resultant alpha-Fe2O3 nanotubes were characterized by XRD, SEM, TEM, and VSM techniques. The hollow structure is mainly influenced by the water content in the gel precursor and the heating rate, and the hollow formation mechanism of alpha-Fe2O9 nanotubes is discussed. Adsorption of BSA onto the as-prepared alpha-Fe2O3 nanotubes exhibits a good capacity of 56.5 mg/g with the initial BSA concentration of 1.0 mg/mL, which demonstrates their feasibility in delivery of biomacromolecules. Subsequently, the adsorption characteristics of DNA onto the alpha-Fe2O3 nanotubes were investigated, and the adsorbance of DNA can achieve a maximum value of 4.19 microg/g when the initial DNA concentration is 50 microg/mL. The adsorption process of DNA onto alpha-Fe2O3 nanotubes can be described well by the pseudo-first-order kinetic model at room temperature according to the correlation coefficient R2 = 0.9978.

Immobilization and Characterization of Penicillin G Acylase (PGA) Immobilized on Magnetic Ni0.5Zn0.5Fe2O4 Nanoparticles.

Magnetic Ni0.5Zn0.5Fe2O4 nanoparticles were prepared via the solution combustion process and their microstructure and magnetic properties were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM). The as-prepared magnetic Ni0.5Zn0.5Fe2O4 nanoparticles are characterized with average grain size of about 20 nm and magnetization of 90.3 Am²/kg. The surface of magnetic Ni0.5Zn0.5Fe2O4 nanoparticles was modified by use of sodium silicate and N-(3-Dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride, and the penicillin G acylase (PGA) was successfully immobilized on the surface-modified magnetic Ni0.5Zn0.5Fe2O4 nanoparticles. The results show that the activity for the immobilized PGA is affected less by pH and temperature than that for the free PGA, and the immobilized PGA exhibits a high effective activity, good stability of enzyme catalyst. This immobilized PGA on magnetic Ni0.5Zn0.5Fe2O4 nanoparticles can be separated from the solution by the external magnetic field for cyclic utilization, and they could retain about 70% of initial enzyme activity after 11 consecutive operations. The kinetic parameters (Km and Vmax) were determined, and the value of Km for the immobilized PGA (204.53 mmol/L) is higher than that of the free enzyme (3.50 mmol/L), while Vmax (1.93 mmol/min) is also larger than that of the free enzyme (0.838 mmol/min).

Surgically treated solitary giant gluteal and retroperitoneal neurofibroma: a case report.

BACKGROUND: Giant neurofibromas in patients with neurofibromatosis type 1 involve multiple regions and are often difficult to surgically extirpate. However, surgical intervention is the most effective means for improving quality of life. The case reported herein is unique in that it involves a giant neurofibroma, involving the patient's peritoneal and pelvic cavities, retroperitoneal space, and buttock, which was causing compressive displacement of abdominal and pelvic organs. A challenging surgical intervention was required to accomplish near-total resection to relieve organ compression while preserving visceral and genitoanal function. CASE PRESENTATION: The case reported is of a patient presenting with a solitary giant retroperitoneal neurofibroma that threatened to obliterate both peritoneal and pelvic cavities and protruded conspicuously into the right gluteal region. The enormous dumbbell-shaped mass was surgically removed in three parts. Postoperative pathology studies confirmed a diagnosis of neurofibroma. Follow-up computed tomography images taken three months postoperatively revealed residual tumor in the perianal region. The patient's quality of life had measurably improved on follow-up at eight months. CONCLUSIONS: Surgical intervention in such extraordinary circumstances of a giant neurofibroma causing compressive displacement of critical organs reduces tumor burden, restores appearance and function of patient's body and internal organs, and improves the patient's quality of life.

The association between oxidative stress, activator protein-1, inflammatory, total antioxidant status and artery stiffness and the efficacy of olmesartan in elderly patients with mild-to-moderate essential hypertension.

This study investigated the change of oxidative stress, activator protein-1 (AP-1), inflammatory, total antioxidant status (TAS) and artery stiffness, and explored the relationship between these characteristics and the efficacy of olmesartan intervention in elderly patients with mild-to-moderate essential hypertension (EH). In total, 386 elderly patients with EH and 353 normotensive controls were recruited. All study subjects had oxidative stress markers, AP-1, inflammatory factors, TAS and brancial-ankle artery pulse wave velocity (ba-PWV) measured. In total, 193 elderly patients with EH were randomized to olmesartan and were matched with 193 normotensive controls to observe the change of index above mentioned before and after the treatment. Compared with the controls, superoxide dismutase (SOD) and TAS were significantly reduced in patients with EH, and malondialdehyde (MDA), AP-1, high-sensitivity C-reactive protein (Hs-CRP), Monocyte Chemoattractant Protein-1 (MCP-1), heart rate， endothelin-1 (ET-1), TAS and ba-PWV were significantly increased (P < 0.01 for all). Pearson's correlation analysis showed that SOD and TAS were negatively related to AP-1 (P < 0.05 for all), and that blood pressure (BP), age, MDA, Hs-CRP, MCP-1, ET-1 were positively related to AP-1 (P < 0.01 for all). Multivariate linear regression analysis showed that BP, SOD, MDA, AP-1, Hs-CRP, MCP-1, ET-1, TAS, heart rate and age were independent risk factors for ba-PWV. After treatment with olmesartan, SOD and TAS were increased, while BP, heart rate, AP-1 and inflammatory factors were reduced with significant improvement in ba-PWV (P < 0.05 for all). More increase of arterial stiffness was reported in elderly hypertensive patients with greater oxidative stress, inflammatory, AP-1, heart rate, and lower TAS. Higher oxidative stress, AP-1 and inflammatory may predict higher arterial stiffness. Olmesartan may increase TAS, yet inhibit oxidative stress, AP-1, inflammatory, and heart rate with improved artery stiffness in elderly hypertensive patients.

Severe Mechanical Hemolysis After Transcatheter Closure of a Traumatic Ventricular Septal Defect Using the Amplatzer Atrial Septal Occluder.

Traumatic ventricular septal defect (VSD) resulting from chest trauma, either penetrating or blunt, is a relatively rare occurrence. Herein, we describe the case of a previously healthy 26-year-old man who presented with congestive heart failure, which was secondary to a large traumatic VSD following violent blunt chest trauma. The traumatic VSD was initially closed percutaneously using an Amplatzer atrial septal defect occluder. Post-device closure, however, the patient developed severe intravascular hemolysis refractory to medical treatment. The patient subsequently underwent surgical removal of the Amplatzer device, with concomitant VSD patch closure.

Improvement in efficiency of micromorph tandem silicon solar cells by designing proper interfaces.

Efficient light management for micromorph tandem solar cells is achieved in this Letter by the combined application of TiO(2) and SiO(x) interlayers. Here, TiO(2) is incorporated into a ZnO/a-Si interface as an antireflection layer and SiO(x) is incorporated into an a-Si/µc-Si interface as an intermediate reflecting layer. Solar cells with such architecture not only increase the light absorption but also reduce the mismatch losses of current between the top and bottom cells. The key results, as evidenced by the spectral response measurements, are that the total photocurrent increases from 22.62 to 24.35 mA/cm(2), as well as the short circuit current density of the two component cells is reached to a delicate balance. The influences of the interlayer thickness and morphology on the improvement have been investigated using an electromagnetic simulation in order to take full advantage of this design.

Performance enhancement in a-Si:H/µc-Si:H tandem solar cells with periodic microstructured surfaces.

Here we report on an efficient light-coupling scheme with a periodic microstructured surface to enhance the performance of thin film silicon solar cells. The centerpiece of the surface structure is the hemispherical pit arrays (HPAs), which are fabricated using an inexpensive and scalable process. The integration of HPAs into micromorph tandem thin film silicon solar cells leads to superior broadband reflection suppression properties. With this design, the reflection losses of the tandem cell are reduced to only 1.5%. We demonstrate an efficiency increase from 11.67% to 12.23% compared to a conventional cell with a flat surface, with a 4.6% increase in short circuit current density. The surface microstructures reported here can be applied to a variety of photovoltaic devices to further improve their performance.

Asymmetric Dimethyl-L-Arginine is a Biomarker for Disease Stage and Follow-Up of Pulmonary Hypertension Associated with Congenital Heart Disease.

This study investigated the clinical value of plasma asymmetrical dimethyl-L-arginine (ADMA) level in the diagnosis, staging, and treatment response in congenital heart disease (CHD) patients with pulmonary arterial hypertension (PAH). This was a single-center prospective observational study in 80 CHD patients. Plasma ADMA levels were measured by enzyme-linked immunosorbent assay. Plasma ADMA levels were significantly increased in CHD patients with PAH compared with CHD patients without PAH (P < 0.01) and healthy controls (P < 0.001). In CHD patients with severe PAH, plasma ADMA levels were significantly higher in patients with Eisenmenger's syndrome (ES) than in patients exhibiting low pulmonary vascular resistance (P < 0.001). The plasma ADMA levels significantly correlated with pulmonary arterial pressure (P < 0.001) and pulmonary vascular resistance (P < 0.001) in patients with CHD. Severe PAH was identified by plasma ADMA with a cutoff value of 0.485 µmol/L (P < 0.001) with a specificity of 82.8 % and a sensitivity of 90 %. ES was identified by plasma ADMA with a cutoff value of 0.85 µmol/L (P < 0.05) with a specificity of 85.2 % and a sensitivity of 64.3 %. ADMA levels were significantly decreased after sildenafil therapy for 6 months compared with before therapy levels (0.91 ± 0.22 vs. 0.57 ± 0.30, P < 0.01). Our study suggests that plasma ADMA level may be used as a biomarker for identifying PAH in patients with CHD, assessing pulmonary vascular remodeling, and evaluating the treatment response of CHD patients with PAH to sildenafil.

Long-term outcomes of transcatheter closure of ruptured sinus valsalva aneurysms using patent ductus arteriosus occluders.

BACKGROUND: Transcatheter closure (TCC) of ruptured sinus of Valsalva aneurysm (RSVA) is an alternative strategy to surgery, but there is a lack of long-term outcome data. METHODS AND RESULTS: From 2004 to 2012, 17 patients (8 males, 9 females) were treated with patent ductus arteriosus (PDA) occluders by antegrade venous approach and were followed for 18-102 months. Of the 17 patients, transthoracic echocardiography revealed rupture of the right coronary sinus into the right ventricle in 9 and into the right atrium in 4, and noncoronary sinus rupture into the right ventricle in 3 and into the right atrium in 1. Most (10/17) were in New York Heart Association (NYHA) functional class III or IV. Aortography showed that the size of the defect was 7.71±2.84 mm (4-15 mm). TCC was attempted using PDA occluders 2-5 mm larger than the aortic end of the defects. The device sizes ranged from 8/6 to 18/16 mm (median, 10/8 mm). The procedure was successful in 16 (94.1%), and all of them had complete occlusion at discharge. On a median follow-up of 42 months, 14 patients were in NYHA class I and 2 were in class II, and there was no residual shunt, device embolization, infective endocarditis, or aortic regurgitation. CONCLUSIONS: TCC of RSVA is a safe and effective alternative to surgery with favorable long-term follow-up results.