Operando study of mechanical integrity of high-volume expansion Li-ion battery anode materials coated by Al2O3.

Group IV elements and their oxides, such as Si, Ge, Sn and SiO have much higher theoretical capacity than commercial graphite anode. However, these materials undergo large volume change during cycling, resulting in severe structural degradation and capacity fading. Al2O3coating is considered an approach to improve the mechanical stability of high-capacity anode materials. To understand the effect of Al2O3coating directly, we monitored the morphology change of coated/uncoated Sn particles during cycling using operando focused ion beam-scanning electron microscopy. The results indicate that the Al2O3coating provides local protection and reduces crack formation at the early stage of volume expansion. The 3 nm Al2O3coating layer provides better protection than the 10 and 30 nm coating layer. Nevertheless, the Al2O3coating is unable to prevent the pulverization at the later stage of cycling because of large volume expansion.

Effect of low androgen levels on transient receptor potential channels expression in rat penile corpus cavernosum tissue and its relationship with erectile function.

The exact mechanism by which testosterone deficiency causes ED has not yet been elucidated. TRPC is involved in the process of smooth muscle cell contraction and relaxation. The effect of androgens on TRPCs and their relationship with erectile function are currently unclear. Thirty male SD rats were randomly divided into six groups: control group, castration group, castration + testosterone (T) group (cast + T), control + transfection group (control + trans), control + empty transfection group and castration + transfection group (cast + trans). The transfection group rats were given with lentivirus (1 × 108 TU/mL, 15 µl) carrying the siRNA targeting TRPC4 gene in the rat penile cavernous tissue at 4 weeks after castration. The tests were performed at 5 weeks after castration. Comparing the cast group with the control, the ICPmax/MAP, p-eNOS/eNOS and NO levels in the rat penile tissue were significantly lower (p < 0.01) and the level of TRPC3, TRPC4 and TRPC6 in the rat penile tissue was significantly increased (p < 0.01). When the cast + trans group was compared to the cast group, ICPmax/MAP was markedly higher (p < 0.05), and the level of the TRPC4 was remarkably lower (p < 0.05). Low androgen levels might inhibit an erectile function through up-regulation of the expression of TRPC3, TRPC4 and TRPC6 in rat penile cavernous tissue. Inhibition the level of TRPC4 in rat penile tissue may improve the erectile function in low androgen levels.

Effect of Cationic (Na+) and Anionic (F-) Co-Doping on the Structural and Electrochemical Properties of LiNi1/3Mn1/3Co1/3O2 Cathode Material for Lithium-Ion Batteries.

Elemental doping for substituting lithium or oxygen sites has become a simple and effective technique to improve the electrochemical performance of layered cathode materials. Compared with single-element doping, this work presents an unprecedented contribution to the study of the effect of Na+/F- co-doping on the structure and electrochemical performance of LiNi1/3Mn1/3Co1/3O2. The co-doped Li1-zNazNi1/3Mn1/3Co1/3O2-zFz (z = 0.025) and pristine LiNi1/3Co1/3Mn1/3O2 materials were synthesized via the sol-gel method using EDTA as a chelating agent. Structural analyses, carried out by X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy, revealed that the Na+ and F- dopants were successfully incorporated into the Li and O sites, respectively. The co-doping resulted in larger Li-slab spacing, a lower degree of cation mixing, and the stabilization of the surface structure, which substantially enhanced the cycling stability and rate capability of the cathode material. The Na/F co-doped LiNi1/3Mn1/3Co1/3O2 electrode delivered an initial specific capacity of 142 mAh g-1 at a 1C rate (178 mAh g-1 at 0.1C), and it maintained 50% of its initial capacity after 1000 charge-discharge cycles at a 1C rate.

Accurate Sybil Attack Detection Based on Fine-Grained Physical Channel Information.

With the development of the Internet-of-Things (IoT), wireless network security has more and more attention paid to it. The Sybil attack is one of the famous wireless attacks that can forge wireless devices to steal information from clients. These forged devices may constantly attack target access points to crush the wireless network. In this paper, we propose a novel Sybil attack detection based on Channel State Information (CSI). This detection algorithm can tell whether the static devices are Sybil attackers by combining a self-adaptive multiple signal classification algorithm with the Received Signal Strength Indicator (RSSI). Moreover, we develop a novel tracing scheme to cluster the channel characteristics of mobile devices and detect dynamic attackers that change their channel characteristics in an error area. Finally, we experiment on mobile and commercial WiFi devices. Our algorithm can effectively distinguish the Sybil devices. The experimental results show that our Sybil attack detection system achieves high accuracy for both static and dynamic scenarios. Therefore, combining the phase and similarity of channel features, the multi-dimensional analysis of CSI can effectively detect Sybil nodes and improve the security of wireless networks.

Hard X-ray-induced damage on carbon-binder matrix for in situ synchrotron transmission X-ray microscopy tomography of Li-ion batteries.

The electrode of Li-ion batteries is required to be chemically and mechanically stable in the electrolyte environment for in situ monitoring by transmission X-ray microscopy (TXM). Evidence has shown that continuous irradiation has an impact on the microstructure and the electrochemical performance of the electrode. To identify the root cause of the radiation damage, a wire-shaped electrode is soaked in an electrolyte in a quartz capillary and monitored using TXM under hard X-ray illumination. The results show that expansion of the carbon-binder matrix by the accumulated X-ray dose is the key factor of radiation damage. For in situ TXM tomography, intermittent X-ray exposure during image capturing can be used to avoid the morphology change caused by radiation damage on the carbon-binder matrix.

A new medical device applied in a case of acute fecal impaction with overflow diarrhea: a case report.

BACKGROUND: Fecal impaction is a digestive system disease, that is most common in the elderly population and becomes more prevalent with increasing age. Manual removal can successfully remove the impaction in 80% of fecal impaction cases. In severe cases, endoscopy and surgery may be necessary. CASE PRESENTATION: A 78-year-old Han Chinese man living in a nursing home was diagnosed with fecal impaction; his initial symptom was overflow diarrhea, which is a rare occurrence with regard to fecal impaction. Nevertheless, we were able to effectively treat this situation by employing a new medical device that presents a novel method for addressing fecal impaction. CONCLUSION: Early identification of fecal impaction with atypical symptoms is crucial to provide proper emergency management. A safe and noninvasive treatment method, especially for elderly patients with fecal impaction, should be chosen.

Low testosterone state inhibits erectile function by downregulating the expression of GIT1 in rat penile corpus cavernosum.

Background: The mechanism of erectile dysfunction (ED) caused by a low androgen level is still not clear. Aim: To explore the influence of the low testosterone state on G protein-coupled receptor kinase interactor 1 (GIT1) and its contact to erectile function. Methods: Thirty male Sprague-Dawley rats aged 8 weeks were distributed at random into 5 groups: control (sham operated), castration, testosterone supplement after castration, castration + vacant lentiviral transfection, and castration + lentiviral transfection. The testis and epididymis were removed through a scrotal incision to develop castrated rats. Four weeks after castration, a lentivirus carrying the GIT1 gene was injected into the middle of rat penile corpus cavernosum. One week after transfection, maximum intracavernous pressure/mean arterial pressure (ICPmax/MAP), serum testosterone, nitric oxide, GIT1, endothelial nitric oxide synthase (eNOS), phospho-eNOS (p-eNOS), p-eNOS/eNOS, and the interaction between eNOS and GIT1 were assessed in the rats. Outcomes: The levels of GIT1 in the penile cavernous tissue of castrated rats are significantly lower than that of controls. Results: GIT1 was expressed in the cytoplasm and cell membrane of vascular endothelial cells and smooth muscle cells in rat penile tissue. In comparison with normal rats, the castrated rats showed lower levels of GIT1 expression, GIT1 and eNOS interaction, p-eNOS/eNOS, nitric oxide, and ICPmax/MAP (P < .01). Overexpression of GIT1 can intensively enhance the expression level of GIT1, the interaction between GIT1 and eNOS, p-eNOS/eNOS, nitric oxide, and ICPmax/MAP in rats (P < .01). Clinical Translation: Modulating the interaction between eNOS and GIT1 might be a novel method of treating ED caused by a low androgen level. Strengths and Limitations: The impact of GIT1 phosphorylation on the activity of eNOS and its possible mechanisms affecting erectile function require further study. Conclusion: A low testosterone state inhibits erectile function in rats by reducing the expression of GIT1 and the protein interaction between GIT1 and eNOS.

Silver Nanocoating of LiNi0.8Co0.1Mn0.1O2 Cathode Material for Lithium-Ion Batteries.

Surface coating has become an effective approach to improve the electrochemical performance of Ni-rich cathode materials. In this study, we investigated the nature of an Ag coating layer and its effect on electrochemical properties of the LiNi0.8Co0.1Mn0.1O2 (NCM811) cathode material, which was synthesized using 3 mol.% of silver nanoparticles by a facile, cost-effective, scalable and convenient method. We conducted structural analyses using X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy, which revealed that the Ag nanoparticle coating did not affect the layered structure of NCM811. The Ag-coated sample had less cation mixing compared to the pristine NMC811, which could be attributed to the surface protection of Ag coating from air contamination. The Ag-coated NCM811 exhibited better kinetics than the pristine one, which is attributed to the higher electronic conductivity and better layered structure provided by the Ag nanoparticle coating. The Ag-coated NCM811 delivered a discharge capacity of 185 mAh·g-1 at the first cycle and 120 mAh·g-1 at the 100th cycle, respectively, which is better than the pristine NMC811.

Effects of various catheter fix sites on catheter-associated lower urinary tract symptoms.

The present study aimed to compare the effects of various catheter fix sites on catheter-associated lower urinary tract symptoms (CALUTS) in 450 patients who underwent surgical removal of upper urinary calculi 24 h earlier. All patients had 16 French Foley catheters inserted and the balloons were filled. In group A, the catheters were fixed on the top one-third of the thigh. In group B, the catheters were fixed on the abdominal wall. Patients in whom the catheters were neither fixed on the thigh nor abdominal wall were designated as controls. There were 150 patients in each group. CALUTS, such as frequency, urgency, burning during micturition, odynuria, bladder pain and other symptoms, including urethral discharge, a red and swollen external urethral orifice, catheter traction or blockage and catheter-associated discomfort were recorded. Patients in group A compared with the control group had a significantly lower incidence of frequency, urgency, odynuria, urethral discharge, catheter traction and catheter-associated discomfort (P<0.05). Patients in group B were observed to have a significantly lower incidence of urgency, urethral discharge, catheter traction and catheter-associated discomfort compared with the control group (P<0.05), but a higher incidence of odynuria, urethral pain, urethral discharge and a red and swollen external urethral orifice compared with group A (P<0.05). An additional catheter fixation site for bedridden patients was necessary and an additional fix site on the thigh was preferred to the abdominal wall, which may further reduce catheter-associated lower urinary tract symptoms.

In-Situ Characterization of Dynamic Morphological and Phase Changes of Selenium-doped Germanium Using a Single Particle Cell and Synchrotron Transmission X-ray Microscopy.

The dynamic information of lithium-ion battery active materials obtained from coin cell-based in-situ characterizations might not represent the properties of the active material itself because many other factors in the cell could have impacts on the cell performance. To address this problem, a single particle cell was developed to perform the in-situ characterization without the interference of inactive materials in the battery electrode as well as the X-ray-induced damage. In this study, the dynamic morphological and phase changes of selenium-doped germanium (Ge0.9 Se0.1 ) at the single particle level were investigated via synchrotron-based in-situ transmission X-ray microscopy. The results demonstrate the good reversibility of Ge0.9 Se0.1 at high cycling rate that helps understand its good cycling performance and rate capability. This in-situ and operando technique based on a single particle battery cell provides an approach to understanding the dynamic electrochemical processes of battery materials during charging and discharging at the particle level.

Nanostructured Molybdenum-Oxide Anodes for Lithium-Ion Batteries: An Outstanding Increase in Capacity.

This work aimed at synthesizing MoO3 and MoO2 by a facile and cost-effective method using extract of orange peel as a biological chelating and reducing agent for ammonium molybdate. Calcination of the precursor in air at 450 °C yielded the stochiometric MoO3 phase, while calcination in vacuum produced the reduced form MoO2 as evidenced by X-ray powder diffraction, Raman scattering spectroscopy, and X-ray photoelectron spectroscopy results. Scanning and transmission electron microscopy images showed different morphologies and sizes of MoOx particles. MoO3 formed platelet particles that were larger than those observed for MoO2. MoO3 showed stable thermal behavior until approximately 800 °C, whereas MoO2 showed weight gain at approximately 400 °C due to the fact of re-oxidation and oxygen uptake and, hence, conversion to stoichiometric MoO3. Electrochemically, traditional performance was observed for MoO3, which exhibited a high initial capacity with steady and continuous capacity fading upon cycling. On the contrary, MoO2 showed completely different electrochemical behavior with less initial capacity but an outstanding increase in capacity upon cycling, which reached 1600 mAh g-1 after 800 cycles. This outstanding electrochemical performance of MoO2 may be attributed to its higher surface area and better electrical conductivity as observed in surface area and impedance investigations.

Crack-Free Silicon Monoxide as Anodes for Lithium-Ion Batteries.

The volume expansion of Si and SiO particles was investigated using a single-particle battery assembled with a focused ion beam and scanning electron microscopy (FIB-SEM) system. Single Si and SiO particles were galvanostatically charged and discharged as in real batteries. Microstructural changes of the particles were monitored in situ using FIB-SEM from two different angles. The results revealed that the volume expansion of micrometer size particle SiO was not only much smaller than that of Si, but it also kept its original shape with no sign of cracks. This isotropic mechanical property of a SiO particle can be attributed to its microstructure: nanosized Si domains mixed with SiO2 domains. The nanosized Si domains can mitigate the anisotropic swelling caused by the orientation-dependent lithium-ion insertion; the surrounding SiO2 domains can act as a buffer to further constrain the localized anisotropic swelling.

General power-law temporal scaling for unequal-size microbubble coalescence.

We systematically study the effects of liquid viscosity, liquid density, and surface tension on global microbubble coalescence using lattice Boltzmann simulation. The liquid-gas system is characterized by Ohnesorge number Oh≡η_{h}/sqrt[ρ_{h}σr_{F}] with η_{h},ρ_{h},σ, and r_{F} being viscosity and density of liquid, surface tension, and the radius of the larger parent bubble, respectively. This study focuses on the microbubble coalescence without oscillation in an Oh range between 0.5 and 1.0. The global coalescence time is defined as the time period from initially two parent bubbles touching to finally one child bubble when its half-vertical axis reaches above 99% of the bubble radius. Comprehensive graphics processing unit parallelization, convergence check, and validation are carried out to ensure the physical accuracy and computational efficiency. From 138 simulations of 23 cases, we derive and validate a general power-law temporal scaling T^{*}=A_{0}γ^{-n}, that correlates the normalized global coalescence time (T^{*}) with size inequality (γ) of initial parent bubbles. We found that the prefactor A_{0} is linear to Oh in the full considered Oh range, whereas the power index n is linear to Oh when Oh<0.66 and remains constant when Oh>0.66. The physical insights of the coalescence behavior are explored. Such a general temporal scaling of global microbubble coalescence on size inequality may provide useful guidance for the design, development, and optimization of microfluidic systems for various applications.

Risk factors for the fever after percutaneous nephrolithotomy: a retrospective analysis.

BACKGROUND: It's very common to see the onset of fever after percutaneous nephrolithotomy (PCNL), it's necessary to analyze the risk factors for the fever following PCNL, and to provide evidence for infection prevention after PCNL. METHODS: A total of 546 adult PCNL patients were included as study subjects and retrospective studies were performed. We collected clinical data of patients using a prospectively designed database. Univariate and multivariate logistic regression analyses were performed to identify the potential risk factors for the fever after PCNL. RESULTS: Of the included 546 PCNL patients, there were 82 fever patients and 464 no-fever patients following PCNL. Escherichia coli and Proteus mirabilis are the two most common infectious bacteria. Preoperative urinary tract infection (OR =4.38, 95% CI: 1.15-9.53), multiple access (OR =5.31, 95% CI: 1.23-10.75), diabetes (OR =4.97, 95% CI: 1.37-9.86), length of operation ≥60 min (OR =5.67, 95% CI: 2.24-13.42), estimated blood loss in PCNL ≥500 mL (OR=2.78, 95% CI: 2.32-3.61) were the independent risk factors associated with postoperative infection. CONCLUSIONS: Effective control of urinary tract infection, reduction of access number, strict control of blood glucose, length of operation control, reduction of intraoperative bleeding should be considered as measures to prevent postoperative fever for patients with PCNL.

Blade-Type Reaction Front in Micrometer-Sized Germanium Particles during Lithiation.

To investigate the lithium transport mechanism in micrometer-sized germanium (Ge) particles, in situ focused ion beam-scanning electron microscopy was used to monitor the structural evolution of individual Ge particles during lithiation. Our results show that there are two types of reaction fronts during lithiation, representing the differences of reactions on the surface and in bulk. The cross-sectional SEM images and transmission electron microscopy characterizations show that the interface between amorphous LixGe and Ge has a wedge shape because of the higher Li transport rate on the surface of the particle. The blade-type reaction front is formed at the interface of the amorphous LixGe and crystalline Ge and is attributed to the large strain at the interface.

In Situ Focused Ion Beam Scanning Electron Microscope Study of Microstructural Evolution of Single Tin Particle Anode for Li-Ion Batteries.

Tin (Sn) is a potential anode material for highenergy density Li-ion batteries because of its high capacity, safety, abundance and low cost. However, Sn suffers from large volume change during cycling, leading to fast degradation of the electrode. For the first time, the microstructural evolution of micrometer-sized single Sn particle was monitored by focused-ion beam (FIB) polishing and scanning electron microscopy (SEM) imaging during electrochemical cycling by in situ FIB-SEM. Our results show the formation and evolution of cracks during lithiation, evolution of porous structure during delithiation and volume expansion/contraction during cycling. The electrochemical performance and the microstructural evolution of the Sn microparticle during cycling are directly correlated, which provides insights for understanding Sn-based electrode materials.

A Three-Gene Classifier Associated With MicroRNA-Mediated Regulation Predicts Prostate Cancer Recurrence After Radical Prostatectomy.

BACKGROUND AND OBJECTIVE: After radical prostatectomy (RP), prostate cancer (PCa) patients may experience biochemical recurrence (BCR) and clinical recurrence, which remains a dominant issue in PCa treatment. The purpose of this study was to identify a protein-coding gene classifier associated with microRNA (miRNA)-mediated regulation to provide a comprehensive prognostic index to predict PCa recurrence after RP. METHODS: Candidate classifiers were constructed using two machine-learning algorithms (a least absolute shrinkage and selector operation [LASSO]-based classifier and a decision tree-based classifier) based on a discovery cohort (n = 156) from The Cancer Genome Atlas (TCGA) database. After selecting the LASSO-based classifier based on the prediction accuracy, both an internal validation cohort (n = 333) and an external validation cohort (n = 100) were used to examined the classifier using survival analysis, time-dependent receiver operating characteristic (ROC) curve analysis, and univariate and multivariate Cox proportional hazards regression analyses. Functional enrichment analysis of co-expressed genes was carried out to explore the underlying moleculer mechanisms of the genes included in the classifier. RESULTS: We constructed a three-gene classifier that included FAM72B, GNE, and TRIM46, and we identified four upstream prognostic miRNAs (hsa-miR-133a-3p, hsa-miR-222-3p, hsa-miR-1301-3p, and hsa-miR-30c-2-3p). The classifier exhibited a remarkable ability (area under the curve [AUC] = 0.927) to distinguish PCa patients with high and low Gleason scores in the discovery cohort. Furthermore, it was significantly associated with clinical recurrence (p < 0.0001, log rank statistic = 20.7, AUC = 0.733) and could serve as an independent prognostic factor of recurrence-free survival (hazard ratio: 1.708, 95% CI: 1.180-2.472, p < 0.001). Additionally, it was a predictor of BCR according to BCR-free survival analysis (p = 0.0338, log rank statistic = 4.51). CONCLUSIONS: The three-gene classifier associated with miRNA-mediated regulation may serve as a novel prognostic biomarker for PCa patients after RP.

Non-equilibrium electrokinetic micro/nano fluidic mixer.

We propose a new type of micro/nano fluidic mixer based on non-equilibrium electrokinetics and demonstrate its mixing performance. We fabricate the device with two-step reactive ion etching, one for nanochannels and one for microchannels. Mixing is achieved by strong vortex structures formed near the micro/nano channel interface. We expect the proposed device to be beneficial in the development of micro total analysis systems, since it is simple in its design with minimal fabrication complications.

Three-Dimensional Reconstruction and Analysis of All-Solid Li-Ion Battery Electrode Using Synchrotron Transmission X-ray Microscopy Tomography.

A synchrotron transmission X-ray microscopy tomography system with a spatial resolution of 58.2 nm at the Advanced Photon Source was employed to obtain three-dimensional morphological data of all-solid Li-ion battery electrodes. The three-phase electrode was fabricated from a 47:47:6 (wt %) mixture of Li(Ni1/3Mn1/3Co1/3)O2 as active material, Li1.3Ti1.7Al0.3(PO4)3 as Li-ion conductor, and Super-P carbon as electron conductor. The geometric analysis show that particle-based all-solid Li-ion battery has serious contact interface problem which significantly impact the Li-ion transport and intercalation reaction in the electrode, leading to low capacity, poor rate capability and cycle life.

[Application of computed tomographic angiography in repairing skin defect after scalp avulsion with free latissimus dorsi flap transplantation].

OBJECTIVE: To investigate the clinical value of computed tomographic angiography (CTA) and three-dimensional reconstruction technique in repairing scalp avulsion wound with large skull exposure by the free latissimus dorsi flap transplantation. METHODS: Between October 2007 and June 2012, 9 female patients with serious scalp avulsion and large skull exposure were treated, aged 23-54 years (mean, 38 years). The injury causes included machine twist injury in 6 cases, traffic accident injury in 2 cases, and falling from height injury in 1 case. Before admission, 3 patients had scalp necrosis after scalp in situ replantation, and 6 patients underwent debridement and dressing. The time from injury to admission was 8 hours to 7 days (mean, 1 day). The avulsed scalp area ranged from 75% to 90% of the scalp area (mean, 81%); the exposed skull area ranged from 55% to 70% of the scalp area (mean, 63%). Two patients had unilateral auricle avulse. CTA was used to observe the superficial temporal artery and vein, facial artery, external jugular vein, dorsal thoracic artery and vein, and measure the blood vessel diameter before operation. According to the CTA results, the latissimus dorsal skin flaps were desinged to repair wounds in 7 cases, the latissimus dorsal muscle flaps combined with skin graft were used to repair wounds in 2 cases. According to preoperative design, operation was successfully completed in 7 cases; great saphenous vein was used as vascular graft in 2 cases having poor images of superficial temporal vessels. The size of latissimus dorsal skin flaps ranged from 20 cm x 14 cm to 25 cm x 20 cm; the donor site was repaired with skin graft. The size of latissimus dorsal muscle flaps were 23 cm x 16 cm and 16 cm x 10 cm; the donor site was directly sutured. RESULTS: The blood vessel diameter measured during operation was close to the value measured before operation. The operation time was 6-8 hours (mean, 6.5 hours). The latissimus dorsal muscle (skin) flap and skin graft survived, with primary healing of wound or incision at donor site. The patients were followed up 3 months-2 years (mean, 6 months). The flap had soft texture and skin had no ulceration. CONCLUSION: The free latissimus dorsi flaps can repair scalp avulsion with large skull exposure. Preoperative CTA can get the vessel anatomical structure and diameter at donor and recipient sites, which will guide the operation program design and implementation so as to shorten the operation time and improve the accuracy rate of vascular anastomosis.