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Monolayer transition metal dichalcogenides offer an appropriate platform for developing advanced electronics beyond graphene. Similar to two-dimensional molecular frameworks, the electronic properties of such monolayers can be sensitive to perturbations from the surroundings; the implied tunability of electronic structure is of great interest. Using scanning tunneling microscopy/spectroscopy, we demonstrated a bandgap engineering technique in two monolayer materials, MoS

Palladium diselenide (PdSe2), a peculiar noble metal dichalcogenide, has emerged as a new two-dimensional material with high predicted carrier mobility and a widely tunable band gap for device applications. The inherent in-plane anisotropy endowed by the pentagonal structure further renders PdSe2 promising for novel electronic, photonic, and thermoelectric applications. However, the direct synthesis of few-layer PdSe2 is still challenging and rarely reported. Here, we demonstrate that few-layer, single-crystal PdSe2 flakes can be synthesized at a relatively low growth temperature (300 °C) on sapphire substrates using low-pressure chemical vapor deposition (CVD). The well-defined rectangular domain shape and precisely determined layer number of the CVD-grown PdSe2 enable us to investigate their layer-dependent and in-plane anisotropic properties. The experimentally determined layer-dependent band gap shrinkage combined with first-principle calculations suggest that the interlayer interaction is weaker in few-layer PdSe2 in comparison with that in bulk crystals. Field-effect transistors based on the CVD-grown PdSe2 also show performances comparable to those based on exfoliated samples. The low-temperature synthesis method reported here provides a feasible approach to fabricate high-quality few-layer PdSe2 for device applications.

Palladium diselenide (PdSe

Two dehydroacetic acid (DHA, L1H) related imine ligands, L2H and L3H were obtained in moderate yields by reacting DHA with 2,4,6-trimethylaniline and phenylhydrazine, respectively. Refluxing [Ru (η6-p-cymene)Cl2]2 with two equivalents of L1Na, L2H and L3H in methanol generated ruthenium compounds [Ru (η6-p-cymene)Cl (L1)] (1), [Ru (η6-p-cymene)Cl (L2)] (2), [Ru (η6-p-cymene)Cl (L3)] (3), respectively. The chloride atom of 2 and 3 was substituted by ambidentate ligands N3, NCO and NCS to generate a series of ruthenium compounds 4a-4c and 5a-5b. All of these ligands and ruthenium compounds were characterized by 1H and 13C NMR spectroscopy. Compounds 1–3, 4a-4c, and 5a were also structural determined by single crystal X-ray crystallography showing a three-legged piano stool geometry with the p-cymene acting as the seat plane. Anti-proliferative activity study using these ruthenium complexes against PC-3 and DU-145 cell-lines shows that compounds 2 and 4a-4c have the best activity than other ruthenium compounds. The results indicate that the ruthenium p-cymene compounds with large steric hindrance of dehydroacetic acid imine derivative ligands exhibit higher anti-proliferative activity against PC-3 and DU-145 cell-lines.

To study the feasibility and quality of recycled glass phosphor waste for LED packaging, the experiments were conducted to compare optical characteristics between fresh color conversion layer and that made of recycled waste. The fresh color conversion layer was fabricated through sintering pristine mixture of Y.A.G. powder [yellow phosphor (Y3AlO12 : Ce3+). Those recycled waste glass phosphor re-melted to form Secondary Molten Glass Phosphor (S.M.G.P.). The experiments on such low melting temperature glass results showed that transmission rates of S.M.G.P. are 9% higher than those of first-sintered glass phosphor, corresponding to 1.25% greater average bubble size and 36% more bubble coverage area in S.M.G.P. In the recent years, high power LED modules and laser projectors have been requiring higher thermal stability by using glass phosphor materials for light mixing. Nevertheless, phosphor and related materials are too expensive to expand their markets. It seems a right trend and research goal that recycling such waste of high thermal stability and quality materials could be preferably one of feasible cost-down solutions. This technical approach could bring out brighter future for solid lighting and light source module industries.

The high-temperature operation of glass based phosphor-converted warm-white light-emitting diodes (PC-WWLEDs) is demonstrated. The fabrication and characteristics of low-temperature phosphor (Yollow:Ce:3+:YAG, Greed:Tb3+:YAG, Red:CaAlClSiN3:Eu2+) doped glass applied to high color rendering indices warm-white-light-emitting diodes was presented. In this property is color coordinates (x, y) = (0.32, 0.28), quantum yield (QY) = 55%, color rending index (CRI) =85, correlated color temperature (CCT) =3900K. The result showed the PC-WLEDs maintained good thermal stability at the high temperature operation. The QY decay, CRI attenuation and chromaticity shift in glass and silicone based high-power PC-WLEDs under thermal aging at 150°C and 250°C are also presented and compared. The result indicated that the glass based PC-WLEDs exhibited better thermal stability than the silicone. And the color rendering indices (CRI) glass phosphor may have potential used as a phosphor layer for high-performance and low-cost PCWLEDs used in next-generation indoors solid-state lighting applications.

Purpose Efficient tumor volume delineation by the combined use of PET/CT scanning is necessary for the proper treatment of non-small cell lung cancer (NSCLC). To understand the effect of variation in background intensity on PET-based gross tumor volume (GTV) delineation, we determined the background standard uptake values (SUVs) in normal lung, aorta (blood pool), and liver tissues and determined GTVs using different methods. Methods Thirty-seven previously untreated patients with pathologically confirmed NSCLC underwent PET/CT scanning with 18 F-fluorodeoxyglucose ( 18 F-FDG). To obtain 18 F-FDG uptake values in normal tissues, regions of interest in the lung lobes (left upper, left lower, right upper, right middle, and right lower), aorta, and liver zones (left, intermediate, and right) were measured. The coefficient of variation (CV) of the SUV was measured for each normal structure. The CT-based GTV (GTV CT ) was considered as the standard to which all PET-based GTVs were compared, and the correlation coefficient was analyzed to compare GTV obtained by the various delineation methods. Linear and logarithmic regression analyses were used to determine the relationship between GTV CT and GTV PET . Results Normal lung tissue showed a significantly lower SUV and less stability than tissue of the aorta or liver. For the lung, aorta, and liver, the maximum SUV (SUV max ) was 0.82±0.32, 2.35±0.37, and 3.24±0.50 (CV: 38.79%, 15.82%, and 15.30%) and average SUV (SUV ave ) was 0.49±0.18, 1.68±0.32, and 2.34±0.36 (CV: 36.38%, 18.92%, and 15.44%), respectively. The SUVs of the lung varied from lobe to lobe. The GTV delineation method using the SUV ave of the lung lobe in which the tumor was found as background in the source-to-background ratio (SBR) method showed the best correlation with the volume of CT-based GTV ( r =0.81). Conclusions Our results show vast variation in the SUV among normal tissues, as well as in the different lung lobes. The tumor volume delineated using the SBR method correlated well with the CT-based tumor volume. We conclude that it is reasonable and precise to contour GTV in patients with NSCLC after taking into account the background intensity of the lung lobe in which the tumor is found.

To observe the therapeutic effect of local antibiotic injection into the female prostate on female urethral syndrome (FUS), and search for an effective treatment for this disease.This study included 163 FUS patients treated in the out-patient department between July 2009 and December 2010. According to the visiting order, the patients were randomly assigned to Groups A (n = 58), B (n = 55) and C (n = 50). All underwent routine treatment. Inaddition Group A received local injection of 2 ml of 80 000 U gentamycin + 2 ml of lidocaine, and Group B 2 ml of normal saline + 2 ml of lidocaine, both injected into the distal segment of the urethral back wall where the female prostate is located, twice a week for 3 weeks. The therapeutic effects were evaluated according to the changes of the patients' independent symptom scores at 2 and 4 weeks after the treatment. Disappearance of the symptoms was considered as "curative" ,1/2 reduction in the symptom score as "obviously effective", 1/2 -1/4 reduction in the symptom score as "effective", and1/4 reduction or increase in the symptom score as "ineffective".At 2 weeks after the treatment, the total effectiveness rate was significantly higher in Group A (77.5%) than in B (67.3%) and C (68.0%) (P0.05), but with no statistically significant difference between B and C (P0.05). At 4 weeks, the total effectiveness rate of Group A was slightly decreased, but still remarkably higher than that of group B or C (P0.05).Local injection of gentamycin into the female prostate is effective for the treatment of female urethral syndrome.

To investigate the relationship between gene polymorphism of CYP2E1, CYP1A1, IL-4 and susceptibility of medicamentosa-like dermatitis induced by trichloroethylene (TCE).35 patients with medicamentosa-like dermatitis induced by TCE were chosen as the patient group, and 35 healthy workers as control group. The real-time quantitative polymerase chain reaction (PCR) with TaqMan minor groove binding (MGB) probes was used to test single nucleotide polymorphisms (SNP) of CYP2E1, CYP1A1 and IL-4 in the patients with medicamentosa-like dermatitis as well as in the control. The genotypes and the frequency of genotype or allele were compared between the patients and control with statistical analysis.The frequency of allele G within CYP1A1 gene (rs1048943) was significantly higher in TCE patients (37.1%) than that in control (P0.05); the frequency of allele T within CYP2E1-1053 C/T was significantly higher in TCE patients (41.4%) than that in control (P0.01); the frequency of T/T within IL-4-588 C/T (rs2243250) was significantly higher in TCE patients (75.0%) than that in control (P0.01), and the frequency of allele T within IL-4-588 C/T (rs2243250) was also significantly higher in TCE patients (87.5%) than that in control (P0.01).The gene polymorphism of CYP2E1, CYP1A1, IL-4 is probably associated with hypersensitivity for the TCE patients with medicamentosa-like dermatitis, and could be one of the genetic factors related to the individual susceptibility to TCE exposure.

Cognitive impairments severely affect the quality of life of patients who undergo brain irradiation, and there are no effective preventive strategies. In this study, we examined the therapeutic potential of electroacupuncture (EA) administered immediately after brain irradiation in rats. We detected changes in cognitive function, neurogenesis, and synaptic density at different time points after irradiation, but found that EA could protect the blood-brain barrier (BBB), inhibit neuroinflammatory cytokine expression, upregulate angiogenic cytokine expression, and modulate the levels of neurotransmitter receptors and neuropeptides in the early phase. Moreover, EA protected spatial memory and recognition in the delayed phase. At the cellular/molecular level, the preventative effect of EA on cognitive dysfunction was not dependent on hippocampal neurogenesis; rather, it was related to synaptophysin expression. Our results suggest that EA applied immediately after brain irradiation can prevent cognitive impairments by protecting against the early changes induced by irradiation and may be a novel approach for preventing or ameliorating cognitive impairments in patients with brain tumors who require radiotherapy.

Objective quality assessment has been widely used in image processing for decades and many researchers have been studying the objective quality assessment method based on human visual system (HVS). Recently the structural similarity (SSIM) is proposed, under the assumption that the HVS is highly adapted for extracting structural information from a scene, and simulation results have proved that it is better than PSNR (or MSE), By deeply studying the SSIM, we find it fails in measuring the badly blurred images. Based on this, we develop an improved method which is called gradient-based structural similarity (GSSIM). Experiment results show that GSSIM is more consistent with HVS than SSIM and PSNR especially for blurred images.