Modification of graphene oxide film properties using KrF laser irradiation

Modification of various properties of graphene oxide (GO) films on SiO₂/Si substrate under KrF laser radiation was extensively studied. X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy and the electrical resistance measurements were employed to correlate the effects of laser irradiation on structural, chemical and electrical properties of GO films under different laser fluences. Raman spectroscopy shows reduced graphene oxide patterns with increased I_2D/I_G ratios in irradiated samples. X-ray photoelectron spectroscopy shows a high ratio of carbon to oxygen atoms in the reduced graphene oxide (rGO) films compared to the pristine GO films. X-ray diffraction patterns display a significant drop in the diffraction peak intensity after laser irradiation. Finally, the electrical resistance of irradiated GO films reduced by about four orders of magnitudes compared to the unirradiated GO films. Simultaneously, reduction and patterning of GO films display promising fabrication technique that can be useful for many graphene-based devices.

Modification of various properties of graphene oxide (GO) films on SiO₂/Si substrate under KrF laser radiation was extensively studied.     

Insomnia treatment in the third trimester of pregnancy reduces postpartum depression symptoms: A randomized clinical trial

Mental health is an important medical issue in perinatal care, and there is increasing evidence that insomnia during pregnancy is associated with postpartum depression (PPD). Therefore, the present study evaluated the effect of insomnia treatment during the third trimester of pregnancy on PPD symptoms. Fifty-four pregnant women with insomnia were randomly assigned to trazodone, diphenhydramine, or placebo treatment. Sleep quality was measured by actigraphy at baseline, and after 2 and 6 weeks of treatment. In addition, depression was assessed 2 and 6 weeks after delivery. Trazodone and diphenhydramine improved sleep profile compared to placebo after 6 weeks of treatment. Further, depressive symptoms were reduced 2 and 6 weeks after delivery in trazodone and diphenhydramine groups compared to placebo. No differences in depressive symptoms were observed between the trazodone and diphenhydramine groups. These findings indicate that insomnia treatment with trazodone or diphenhydramine during the third trimester of pregnancy may prevent PPD.     

Good outcome after liver transplantation for ALD without a 6 months abstinence rule prior to transplantation including post‐transplant CDT monitoring for alcohol relapse assessment – a retrospective study

Alcoholic liver disease (ALD) is the second most common indication for liver transplantation (LT). The utility of fixed intervals of abstinence prior to listing is still a matter of discussion. Furthermore, post‐LT long‐term observation is challenging, and biomarkers as carbohydrate‐deficient transferrin (CDT) may help to identify alcohol relapse. We retrospectively analyzed data from patients receiving LT for ALD from 1996 to 2012. A defined period of alcohol abstinence prior to listing was not a precondition, and abstinence was evaluated using structured psychological interviews. A total of 382 patients received LT for ALD as main (n = 290) or secondary (n = 92) indication; median follow‐up was 73 months (0–213). One‐ and five‐year patient survival and graft survival rates were 82% and 69%, and 80% and 67%, respectively. A total of 62 patients (16%) experienced alcohol relapse. Alcohol relapse did not have a statistically significant effect on patient survival (P = 0.10). Post‐transplant CDT measurements showed a sensitivity and specificity of 84% and 85%, respectively. In conclusion, this large single‐center analysis showed good post‐transplant long‐term results in patients with ALD when applying structured psychological interviews before listing. Relapse rates were lower than those reported in the literature despite using a strict definition of alcohol relapse. Furthermore, post‐LT CDT measurement proved to be a useful supplementary tool for detecting alcohol relapse.     

Competence development among nurses: the process of constant interaction

BACKGROUND: The importance of competence to nursing practice was the motivation for this study, which explored nurses' experience in developing their competence as they progress through their careers. METHODS: In accordance with grounded theory method, data collection and data analysis were performed simultaneously using the constant comparative method. RESULTS: Data revealed that nurses developed competence through an iterative process called "the process of constant interaction." This five-stage process was found to be a complex, ongoing interpersonal dynamic between the nurse and the surrounding world. CONCLUSIONS: Although the nurse is the key player in the process of his or her own competence development, employers have a pivotal responsibility in facilitating the nurse's progress toward ongoing professional competence, which is a key element of the quality of care.     

Fe3O4@Au core–shell hybrid nanocomposite for MRI-guided magnetic targeted photo-chemotherapy

Lasers in Medical Science - The combination of multiple therapeutic and diagnostic functions is fast becoming a key feature in the area of clinical oncology. The advent of nanotechnology promises...     

Enhancement of third order nonlinear optical responses via alteration of the density of states of electrons: VS2–NiS2 hybrid nanostructure

We successfully synthesized VS₂–NiS₂ hybrid nanostructures via a one-pot hydrothermal technique. Microstructural characterizations were carried out by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), UV-visible spectroscopy, and Fourier transform infrared spectroscopy (FTIR). The optical indexes such as n, k, and ε were assessed based on the reflectance spectra data and Kramers–Kronig method. By adding varying amounts of the NiS₂ phase in the hybrid nanostructure, the morphology of the hybrid nanostructures is altered to produce microflowers, nanoflakes, and nanoflowers. These changes affect the nonlinear optical properties. The third order nonlinear optical parameters (n₂, β) were analyzed via a simple and accurate Z-scan technique using different laser powers. The two-photon absorption phenomenon has a significant enhancement effect on the nonlinear absorption process, but the nonlinear refractive behaviour of the different hybrid nanostructures changes from self-defocusing to self-focusing due to the alteration of the electronic state alignment and morphology. The magnitudes of n₂ and β are in the order of 10⁻⁹ cm² W⁻¹ and 10⁻³ cm W⁻¹, respectively. The increasing of the density of states of electrons leads to the improvement of the nonlinear optical responses of the VS₂–NiS₂ hybrid nanostructures in comparison with the pure VS₂ structure. This study demonstrates the great potential of this hybrid nanostructure for optical limiters and modulators as well as photonic devices.

Increasing of the density of states of electrons is an important criterion in nonlinear optical phenomena. The hybridization of VS₂ with NiS₂ leads to the improvement of nonlinear optical properties using in the optical and photonic applications.     

Thyroglobulin increment after thyroid hormone withdrawal is a reliable indicator for the detection of significant remnants or metastases in patients with differentiated thyroid carcinoma

Serum thyroglobulin (Tg) measurement has a pivotal role in the management of differentiated thyroid carcinoma (DTC). Serum Tg increment after thyroid hormone discontinuation seems to be a better predictor of tumor recurrence, however, minimal Tg increment may not be a specific marker. This study tries to evaluate the importance of different levels of Tg increment after thyroid hormone discontinuation. Fifty-five patients (46 females and 9 males with mean age of 41.40 yrs) with DTC, treated with total or subtotal thyroidectomy and radioiodine-131 ((131)I) were studied. Ninety-one per cent of the patients had papillary carcinoma. Serum Tg and thyroid stimulating hormone (TSH) were measured using high sensitive IRMA assays during thyroxine (T4) suppression and after discontinuation of T4 treatment. The mean time interval between Tg on T4 and off T4 was 110.29+/-53.43 days and less than 180 days in all patients. Serum Tg level was increased >or= 1 ng/ml in 25 patients after discontinuation of T4. Of these patients, 17 had metastatic disease or a detectable thyroid remnant. Of 16 patients with unchanged Tg (-1or= 7 ng/ml had residual disease or metastases. If DeltaTg was unchanged or decreased, the negative predictive value was 83.3%. The sensitivity of WB(131)IS was 63.6% for the detection of thyroid remnant or metastases. Our study indicates that DeltaTg is a more reliable indicator of remnant disease than on T4-Tg or off T4-Tg levels.