Influence of sintering atmosphere on the microstructure and water durability of SnO–MgO–P<Subscript>2</Subscript>O<Subscript>5</Subscript> glass

Effects of sintering atmosphere (Ar, air, and O₂) on the sinterability and crystallization at 380–470 °C of 60SnO, 10MgO, 30P₂O₅ (mol%) glass powder, and the water durability of the sintered glass were investigated. Increasing the oxygen partial pressure (P_\textO2 ) (P_{{{\text{O}}_{2} }} ) in the sintering atmosphere enhanced the oxidation tendency of Sn²⁺ to Sn⁴⁺ near the surface region of the glass particles. Therefore, the glass viscosity was increased, resulting in the increase in both the temperature of densification and the temperature at which crystalline phases developed. Phase assemblage and the amounts of crystalline phases were also affected by P_\textO2 . P_{{{\text{O}}_{2} }} . The water durability of the sintered glasses is discussed in terms of the above microstructural parameters.     

Taurine ameliorates alcoholic steatohepatitis via enhancing self-antioxidant capacity and alcohol metabolism

Chronic alcohol consumption or alcohol abuse is the main cause of alcoholic steatohepatitis or further cirrhosis. This study was to exam if the antioxidant capacity and alcohol metabolism in livers of chronic alcohol-fed rats were improved by supplementing taurine (Tau). Rats were randomly divided into four groups with five times per week of treatment: 1) isocaloric solution; 2) 3 g alcohol/kg BW/day; 3) 3 g alcohol/kg BW/day + 1 g taurine (Tau)/kg BW/day; and 4) 3 g alcohol/kg BW/day + 2 g Tau/kg BW/day. A 6-week alcohol consumption resulted in lower (p < 0.05) body weight gain and self-antioxidant capacities, as well as increased (p < 0.05) liver size, serum/hepatic lipids, and AST and ALT values. However, alcohol-fed rats co-treated with Tau have decreased (p < 0.05) liver lipid levels via increasing fecal lipid output and cholesterol metabolism. Besides, co-treatment of Tau also enhanced (p < 0.05) self-antioxidant capacities and alcohol metabolism in livers via enhancing GSH contents, CAT, GSH-Px, ADH, and ALDH activities, but decreasing MDA contents. In a histological examination of rat liver, microvesicular steatosis and necrotic cells were observed in alcohol-fed rats without Tau while largely suppressed microvesicular steatosis and no necrotic cells were observed in alcohol-fed rat supplemented with Tau. Therefore, Tau could be an effective hepatoprotective agent against alcohol-induced damage via enhancing self-antioxidant capacity and alcohol metabolism.     

Influence of heating atmosphere on the properties of stannous phosphate glass

A low-viscosity 60 SnO–40 P₂O₅ (mol%) glass was reheated at 280 °C (about 45 °C above the glass-transition temperature) for 20 min in various atmospheres (Ar, air, and O₂), then the structure- and surface-related properties were examined. It was found that increase in \textP_{\textO 2} {\text{P}}_{{{\text{O}}_{ 2} }} increases surface hardness, reduces optical transmittance, and improves chemical durability. The above phenomena are explained in terms of the increased oxidation tendency of Sn²⁺ to Sn⁴⁺ on the glass surface during reheating in increased \textP_{\textO 2} {\text{P}}_{{{\text{O}}_{ 2} }} .     

Evaluation of a haptics-based virtual reality temporal bone simulator for anatomy and surgery training

Introduction

Virtual reality simulation training may improve knowledge of anatomy and surgical skills. We evaluated a 3-dimensional, haptic, virtual reality temporal bone simulator for dissection training.

Methods

The subjects were 7 otolaryngology residents (3 training sessions each) and 7 medical students (1 training session each). The virtual reality temporal bone simulation station included a computer with software that was linked to a force-feedback hand stylus, and the system recorded performance and collisions with vital anatomic structures. Subjects performed virtual reality dissections and completed questionnaires after the training sessions.

Results

Residents and students had favorable responses to most questions of the technology acceptance model (TAM) questionnaire. The average TAM scores were above neutral for residents and medical students in all domains, and the average TAM score for residents was significantly higher for the usefulness domain and lower for the playful domain than students. The average satisfaction questionnaire for residents showed that residents had greater overall satisfaction with cadaver temporal bone dissection training than training with the virtual reality simulator or plastic temporal bone. For medical students, the average comprehension score was significantly increased from before to after training for all anatomic structures. Medical students had significantly more collisions with the dura than residents. The residents had similar mean performance scores after the first and third training sessions for all dissection procedures.

Discussion

The virtual reality temporal bone simulator provided satisfactory training for otolaryngology residents and medical students.     

Hepatoprotection of silymarin against thioacetamide-induced chronic liver fibrosis

BACKGROUND: Liver fibrosis is chronic liver damage usually caused by alcohol, viruses or other toxins and is characterised by an excessive accumulation of extracellular matrix proteins such as collagen. The aim of this study was to establish an animal model of chronic liver damage and investigate molecular mechanisms of silymarin hepatoprotective effects. RESULTS: Thioacetamide (TAA; 100 mg kg^?1 intraperitoneal (i.p.) injection three times weekly) effectively induced chronic liver fibrosis in male ICR mice. Then 24 ICR mice were randomly divided into four groups: (1) saline (i.p.) + water (gavage); (2) saline (i.p.) + 150 mg kg^?1 silymarin (gavage); (3) 100 mg kg^?1 TAA (i.p.) + water (gavage); (4) 100 mg kg^?1 TAA (i.p.) + 150 mg kg^?1 silymarin (gavage). Eight weeks of TAA treatment resulted in lower body weight, serum cholesterol and triglycerides as well as increased liver size, ALT, AST and LDH values (P < 0.05). These TAA‐induced effects were attenuated by silymarin (P < 0.05); therefore silymarin also ameliorated TAA‐induced liver lesions. Effects of silymarin on TAA‐induced chronic liver damage may be attributed to down‐regulation of hepatic MMP‐2, MMP‐13, TIMP‐1, TIMP‐2, AP‐1, KLF6, TGF‐β1, α‐SMA and COL‐α1. CONCLUSION: A mouse model of chronic liver fibrosis was successfully established by injecting 100 mg kg^?1 TAA three times weekly in male ICR mice. Meanwhile, silymarin showed hepatoprotection against TAA‐induced damage. Copyright © 2011 Society of Chemical Industry     

Direct percutaneous ethanol instillation for treatment of venous malformation in the face and neck

Venous malformations of the face and neck involve multiple anatomical spaces and encase critical neuromuscular structures, making surgical treatment difficult; high recurrence rates and high morbidity are well documented. Various methods of treatment of uncertain value and risk of complications have been advocated. We present our experience in treating five patients with venous malformation in the face and neck by using direct percutaneous ethanol sclerotherapy. Four patients had large lesions (≥3 cm; one patient had two large lesions in the low eyelid), and the other had a mid-sized lesion (1.5–3 cm). Under general or local anaesthesia, one-third to one-quarter cavity volume of ethanol was injected percutaneously, directly into the malformation with under fluoroscopy [de Lorimier AA. Sclerotherapy for venous malformations. J Pediatr Surg 1995;30:188–93; Johnson PL, Eckard DA, Brecheisen MA, Girod DA, Tsue TT. Percutaneous ethanol sclerotherapy of venous malformations of the tongue. Am J Neuroradiol 2002;23:779–82; Pappas DC Jr, Persky MS, Berenstein A. Evaluation and treatment of head and neck venous vascular malformations. Ear Nose Throat J 1998;77:914–22; Lee CH, Chen SG. Direct percutaneous ethanol sclerotherapy for treatment of a recurrent venous malformation in the periorbital region. ANZ J Surg. 2004;74(12):1126–7. ^{[1] , [2] , [3] and [4]} ]. Four patients required two injections. All patients had remission and alleviation of their symptoms, with no major complications. Direct percutaneous injection of absolute ethanol provides a simple and reliable alternative treatment for venous malformation in the face and neck.     

The design of a hand-held K-factor meter using an air-core currenttransformer

This paper describes in detail the design of a portable microcontroller-based K-factor meter, or transformer harmonic derating factor meter. This innovative instrument is based on the recently developed time domain method for K-factor determination. K-factor is measured from the ratio of the rms value of the time derivative of a current to the rms value of this same current. The meter employs the properties of an air-core current transformer, or Rogowski coil, to acquire the time derivative of a current and then numerical integration, of this digitized signal, to obtain the current waveform itself. This method avoids the noise of the numeric differentiation, characteristic of the time domain approach to K-factor measurement, as well as the computational effort of the fast Fourier transform in the frequency domain approach. In addition, the instrument incorporates thermal demand models for both K-factor and rms current to assess transformer harmonic heating over a user selected time interval. A prototype meter, using a MC68HC16 microcontroller, was built and tested with a variety of actual and synthesized power system waveforms     

Molecular Imaging and Preclinical Studies of Radiolabeled Long-Term RGD Peptides in U-87 MG Tumor-Bearing Mice

The Arg–Gly–Asp (RGD) peptide shows a high affinity for α_vβ₃ integrin, which is overexpressed in new tumor blood vessels and many types of tumor cells. The radiolabeled RGD peptide has been studied for cancer imaging and radionuclide therapy. We have developed a long-term tumor-targeting peptide DOTA-EB-cRGDfK, which combines a DOTA chelator, a truncated Evans blue dye (EB), a modified linker, and cRGDfK peptide. The aim of this study was to evaluate the potential of indium-111(¹¹¹In) radiolabeled DOTA-EB-cRGDfK in α_vβ₃ integrin-expressing tumors. The human glioblastoma cell line U-87 MG was used to determine the in vitro binding affinity of the radiolabeled peptide. The in vivo distribution of radiolabeled peptides in U-87 MG xenografts was investigated by biodistribution, nanoSPECT/CT, pharmacokinetic and excretion studies. The in vitro competition assay showed that ¹¹¹In-DOTA-EB-cRGDfK had a significant binding affinity to U-87 MG cancer cells (IC₅₀ = 71.7 nM). NanoSPECT/CT imaging showed ¹¹¹In-DOTA-EB-cRGDfK has higher tumor uptake than control peptides (¹¹¹In-DOTA-cRGDfK and ¹¹¹In-DOTA-EB), and there is still a clear signal until 72 h after injection. The biodistribution results showed significant tumor accumulation (27.1 ± 2.7% ID/g) and the tumor to non-tumor ratio was 22.85 at 24 h after injection. In addition, the pharmacokinetics results indicated that the ¹¹¹In-DOTA-EB-cRGDfK peptide has a long-term half-life (T_1/2λz = 77.3 h) and that the calculated absorbed dose was safe for humans. We demonstrated that radiolabeled DOTA-EB-cRGDfK may be a promising agent for glioblastoma tumor imaging and has the potential as a theranostic radiopharmaceutical.     

Neuro-fuzzy speed control of traveling-wave type ultrasonic motor drive using frequency and phase modulation

This paper presents a Fuzzy Neural Network (FNN) control system for a traveling-wave ultrasonic motor (TWUSM) driven by a dual mode modulation non-resonant driving circuit. First, the motor configuration and the proposed driving circuit of a TWUSM are introduced. To drive a TWUSM effectively, a novel driving circuit, that simultaneously employs both the driving frequency and phase modulation control scheme, is proposed to provide two-phase balance voltage for a TWUSM. Since the dynamic characteristics and motor parameters of the TWUSM are highly nonlinear and time-varying, a FNN control system is therefore investigated to achieve high-precision speed control. The proposed FNN control system incorporates neuro-fuzzy control and the driving frequency and phase modulation to solve the problem of nonlinearities and variations. The proposed control system is digitally implemented by a low-cost digital signal processor based microcontroller, hence reducing the system hardware size and cost. The effectiveness of the proposed driving circuit and control system is verified with hardware experiments under the occurrence of uncertainties. In addition, the advantages of the proposed control scheme are indicated in comparison with a conventional proportional-integral control system.     

Formation and properties of SnO–MgO–P<Subscript>2</Subscript>O<Subscript>5</Subscript> glasses

A new glass system SnO–MgO–P₂O₅ with low viscosity has been developed by a melt-quenching method. Formation, thermal properties, and chemical durability of these glasses have been investigated. For a constant P₂O₅ concentration, the glass formation ability is enhanced with the increasing Sn/(Sn + Mg) ratio. The glasses exhibit low glass transition temperature (T _g = 270–400 °C), low dilatometric softening temperature (T _DS = 290–420 °C), and high thermal expansion coefficient (CTE = 110–160 × 10⁻⁷ K⁻¹). With the increasing Sn/(Sn + Mg) ratio, T _g and T _DS decrease, and CTE increases. When Sn/(Sn + Mg) ratio is varied, the relationship between chemical durability and thermal properties of the present glasses is not consistent with what expected in general cases. It is noted that the glasses with 32–32.5 mol% P₂O₅ exhibit excellent chemical durability and tunable T _g, T _DS, and CTE (by varying Sn/(Sn + Mg) ratio).