Towards high-energy, high-resolution computed tomography via a laser driven micro-spot gamma-ray source

Computed Tomography (CT) is a powerful method for non-destructive testing (NDT) and metrology awakes with expanding application fields. To improve the spatial resolution of high energy CT, a micro-spot gamma-ray source based on bremsstrahlung from a laser wakefield accelerator was developed. A high energy CT using the source was performed, which shows that the resolution of reconstruction can reach 100 μm at 10% contrast. Our proof-of-principle demonstration indicates that laser driven micro-spot gamma-ray sources provide a prospective way to increase the spatial resolution and toward to high energy micro CT. Due to the advantage in spatial resolution, laser based high energy CT represents a large potential for many NDT applications.

High power single-mode delivery of mid-infrared sources through chalcogenide fiber

Mechanically robust and low loss single-mode arsenic sulfide fibers are used to deliver high power mid-infrared sources. Anti-reflection coatings were deposited on the fiber facets, enabling 90% transmission through 20 cm length fibers. 10.3 W was transmitted through an anti-reflection coated fiber at 2053 nm, and uncoated fibers sustained 12 MW/cm² intensities on the facet without failure. A Cr:ZnSe laser transmitted >1 W at 2520 nm, and a Fe:ZnSe laser transmitted 0.5 W at 4102 nm. These results indicate that by improving the anti-reflection coatings and using a high beam quality mid-infrared source, chalcogenide fibers can reliably deliver ≥10 W in a single mode, potentially out to 6.5 µm.

[Effects of different concentrations of MgSiF(6) as electrolyte for micro-arc oxidation on the bond strength between titanium and porcelain]

Objective: To investigate the effects of different concentrations of MgSiF(6) as electrolyte on the bond strength between titanium and porcelain after micro-arc oxidation (MAO) treatment and screen the suitable concentration of MgSiF(6) that can improve the bond strength between titanium and porcelain. Methods: Four different concentrations of MgSiF(6) (10, 20, 30, 40 g/L) were chosen as MAO reaction solutions. Sandblasting treatment was selected as a control group. After porcelain was fused to each specimen, titanium-porcelain bond strengths were evaluated by the three-point bending test according to ISO 9693. Scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) were adopted to evaluate the morphologies and elemental compositions of both the MAO coatings and the interfaces of the titanium-porcelain restoration. Results: The surface of titanium specimen in the control group was sharp and rough, while specimens in both 10 g/L group and 20 g/L group were porous and homogeneous. However, the pores found on the specimens in the latter group were larger in diameter (approximately 1.0-2.0 μm) than those on the former one (0.2-0.5 μm). The bond strengths of the control group and the experimental groups (10, 20, 30, 40 g/L MgSiF(6)) were (27.08±3.16), (38.18±2.65), (44.75±2.21), (36.44±2.04), (31.04±2.59) MPa, respectively. All the experimental groups showed higher bond strengths than the control group did (P<0.05), and the bond strength of 20 g/L MgSiF(6) group was significantly higher than those of the other groups (P<0.05). Besides, the interfaces between titanium and porcelain were tight and compact in the 20 g/L group, while different amounts of pores and cracks were visible in the other groups. Additionally, after the three-point bending test, few residual porcelains could be observed on the surfaces of specimens in the control group. Conclusions: MAO treatment with 20 g/L MgSiF(6) on titanium can improve bonding strength between titanium and porcelain.

The State of Lipid Control in Patients with Diabetes in a Public Health Care Centre

Achieving treatment targets has been difficult in treating diabetic patients. This cross-sectional study describes the lipid profiles of patients with diabetes mellitus at a public primary health care centre in Sarawak, Malaysia. The targets for lipid control were based on the International Diabetes Federation recommendation (2002). 1031 patients (98% Type 2 Diabetes) were studied. Fasting lipid profiles were available in 990 (96%) patients. The mean total cholesterol was 5.3 ± 1.0 mmol/L, Triglycerides 1.90 ± 1.26 mmol/L, HDL-C 1.28 ± 0.33 mmol/ L and LDL-C 3.2 ± 0.9 mmol/L. Overall, 22% of patients achieved the treatment target for LDL-C level <2.6mmol/L. 67% of patients had HDL-C > 1.1 mmol/L and 42% of patients had a target TG level below 1.5 mmol/L. Of the 40% of patients who received lipid-lowering drug, 17% achieved LDL-C target, 50% had LDL-C 2.6-4.4mmol/ L and 33% have LDL-C > 4.0 mmol/L. For the remaining 60% not receiving any lipid lowering therapy, 68% had LDL-C between 2.6-4.0 mmol/L and 7% had LDL-C level > 4 mmol/L. Dyslipidemia is still under-treated despite the availability of effective pharmacological agents and the greatly increased risk of cardiovascular diseases in diabetic patients. Asia Pac J Public Health 2007; 19(3): 16-21.

Outbreak Investigation of NADC30-Like PRRSV in South-East China

Epidemiological outbreak investigations were conducted on NADC30-like porcine reproductive and respiratory syndrome virus (PRRSV) to investigate the prevalence of the disease in south-east China in 2015. Two more provinces were found to have NADC30-like PRRSV circulating besides previously reported six provinces. Phylogenetic analysis showed that these virus isolates were clustered in an independent branch and shared high nucleotide similarity to NADC30, a type 2 PRRSV that has been isolated in Unite States in 2008. One NADC30-like PRRSV strain from Henan province was successfully isolated on porcine alveolar macrophages and was tested on 6-week-old specific pathogen-free pigs for pathogenic study. The virus-inoculated pigs showed typical PRRSV clinical symptoms, but all pigs survived throughout the study with a period of 14 days. At necropsy, the lungs of infected pigs developed PRRSV-specific interstitial pneumonia, and virus antigen was detected in lung samples. Therefore, our results indicated NADC30-like PRRSV has widely spread in China and could cause clinical disease on pigs.

The role of organisational support in teleworker wellbeing: a socio-technical systems approach

The prevalence of telework and other forms of mobile working enabled by digital technology is increasing markedly. Following a socio-technical systems approach, this study aims to examine the role of organisational social support and specific support for teleworkers in influencing teleworker wellbeing, the mediating role of social isolation, potentially resulting from a person-environment mismatch in these relationships, and possible differences in these relationships between low-intensity and hybrid teleworkers. Teleworkers' (n = 804) perceptions of support and telework outcomes (psychological strain, job satisfaction, and social isolation) were collected using an on-line survey of teleworking employees distributed within 28 New Zealand organisations where knowledge work was undertaken. Organisational social support and teleworker support was associated with increased job satisfaction and reduced psychological strain. Social isolation mediated the relationship between organisational social support and the two outcome variables, and some differences were observed in the structural relationships for hybrid and low-intensity teleworker sub-samples. These findings suggest that providing the necessary organisational and teleworker support is important for enhancing the teleworker-environment fit and thereby ensuring desirable telework outcomes.

Inhibition of transforming growth factor β (TGF-β) signaling can substitute for Oct4 protein in reprogramming and maintain pluripotency

Mouse pluripotent stem cells (PSCs), such as ES cells and induced PSCs (iPSCs), are an excellent system to investigate the molecular and cellular mechanisms involved in early embryonic development. The signaling pathways orchestrated by leukemia inhibitor factor/STAT3, Wnt/β-catenin, and FGF/MEK/ERK play key roles in the generation of pluripotency. However, the function of TGF-β signaling in this process remains elusive. Here we show that inhibiting TGF-β signaling with its inhibitor SB431542 can substitute for Oct4 during reprogramming. Moreover, inhibiting TGF-β signaling can sustain the pluripotency of iPSCs and ES cells through modulating FGF/MEK/ERK signaling. Therefore, this study reveals a novel function of TGF-β signaling inhibition in the generation and maintenance of PSCs.

Hypercalcemic crisis - a fatal case of primary hyperparathyroidism

The scapula is a flat, triangular bone overlying the posterior chest wall and forming the posterior aspect of the shoulder girdle. To the best of our knowledge, there is no previous description of a notch of the medial aspect of the superior border of the scapula in the literature. The imaging findings of a supero-medial scapula border notch mimicking a bone tumour are presented in this case report.