Electronic, dielectric and optical properties of two dimensional and bulk ice: a multi-scale simulation study

The intercalated water into nanopores exhibits anomalous properties such as ultralow dielectric constant.~Multi-scale modeling and simulations are used to investigate the dielectric properties of various crystalline two-dimensional ices and bulk ices. Although, the structural properties of two-dimensional (2D-) ices have been extensively studied, much less is known about their electronic and optical properties. First, by using density functional theory (DFT) and density functional perturbation theory (DFPT), we calculate the key electronic, optical and dielectric properties of 2D-ices. Performing DFPT calculations, both the ionic and electronic contributions of the dielectric constant are computed. The in-plane electronic dielectric constant is found to be larger than the out-of-plane dielectric constant for all the studied 2D-ices. The in-plane dielectric constant of the electronic response is found to be isotropic for all the studied ices. Secondly, we determined the dipolar dielectric constant of 2D-ices using molecular dynamics simulations (MDS) at finite temperature. The total out-of-plane dielectric constant is found to be larger than 2 for all the studied 2D-ices. Within the framework of the random-phase approximation (RPA), the absorption energy ranges for 2D-ices are found to be in the ultraviolet spectra. For the comparison purposes, we also elucidate the electronic, dielectric and optical properties of four crystalline ices (ice VIII, ice XI, ice Ic and ice Ih) and bulk water

Structurally Tunable pH-responsive Phosphine Oxide Based Gels by Facile Synthesis Strategy

Design and synthesis of nanostructured responsive gels have attracted increasing attention, particularly in the biomedical domain. Polymer chain configurations and nanodomain sizes within the network can be used to steer their functions as drug carriers. Here, a catalyst-free facile one-step synthesis strategy is reported for the design of pH-responsive gels and controlled structures in nanoscale. Transparent and impurity free gels were directly synthesized from trivinylphosphine oxide (TVPO) and cyclic secondary diamine monomers via Michael addition polymerization under mild conditions. NMR analysis confirmed the consumption of all TVPO and the absence of side products, thereby eliminating post purification steps. The small-angle X-ray scattering (SAXS) elucidates the nanoscale structural features in gels, that is, it demonstrates the presence of collapsed nanodomains within gel networks and it was possible to tune the size of these domains by varying the amine monomers and the nature of the solvent. The fabricated gels demonstrate structure tunability via solvent–polymer interactions and pH specific drug release behavior. Three different anionic dyes (acid blue 80, acid blue 90, and fluorescein) of varying size and chemistry were incorporated into the hydrogel as model drugs and their release behavior was studied. Compared to acidic pH, a higher and faster release of acid blue 80 and fluorescein was observed at pH 10, possibly because of their increased solubility in alkaline pH. In addition, their release in phosphate buffered saline (PBS) and simulated body fluid (SBF) matrix was positively influenced by the ionic interaction with positively charged metal ions. In the case of hydrogel containing acid blue 90 a very low drug release (<1%) was observed, which is due to the reaction of its accessible free amino group with the vinyl groups of the TVPO. In vitro evaluation of the prepared hydrogel using human dermal fibroblasts indicates no cytotoxic effects, warranting further research for biomedical applications. Our strategy of such gel synthesis lays the basis for the design of other gel-based functional materials

Second-generation colon capsule endoscopy for detection of colorectal polyps: A meta-analysis

Background: Colorectal cancer counts as the third prevalent type of cancer and the fourth cause of death worldwide. The second-generation colon capsule endoscopy (CCE-2) is a new technology for the diagnosis of colon cancer. The aim of this review was to provide information on the diagnostic accuracy (diagnostic effectiveness) of the second-generation colon capsule endoscopy compared to colonoscopy for the diagnosis of colon cancer and disorders. Methods: A systematic review of literature in PubMed, Scopus, Science Direct, and Cochrane Library and Iranian databases, such as MagIran, SID, Irandoc, the grey literature (via Google Scholar) was conducted on February 30, 2018. QUADAS-2 was used to assess the quality of the studies. MetaDiSc 2.0 software was used for the meta-analysis. Results: In this review, 480 records were identified. Eight prospective cohort articles were included among which 7 included in the meta-analysis. For the diagnosis of colorectal polyps with a diameter of 6-10 mm, the pooled sensitivity and specificity were 84 (95 CI, 80 -88) and 88 (95CI, 85 -90). For the diagnosis of 10 mm or bigger colorectal polyps, the pooled sensitivity and specificity were 84 (95 CI, 76-89) and 96 (95 CI, 94 -97). The sensitivity and specificity of the capsule in the detection of any size polyps were 93 (95 CI, 97-84) and 66 (95 CI, 48-81), respectively. Conclusion: There is little evidence to show the accuracy of CCE-2. Nevertheless, this review showed that the second-generation colon capsule endoscopy has good accuracy in the detection of polyps and colorectal cancer among high- and middle-risk patients. © 202

Multiplex PCR for Identification of Vibrio cholerae Genes

Cholera has re-emerged as a major infectious disease in the recent past, with a global increase in its incidence. This study was focused on Prevalence of ace, tcpA, zot and ctxA genes in Vibrio cholerae strains associated cholera epidemic in 2005, Iran. Number of Thirty-nine strains of Vibrio cholerae Mated to cholera epidemic obtained from different provinces in 2005 in Iran. All the isolates identified by using standard bacteriological methods. Multiplex Polymerase Chain Reaction performed for identification of ctxa,tcpa,ace,zot. All the isolates were inaba O1, Of thirty nine inaba 100 were positive for ace and zot,89.74 presented ctxa and 84.61 showed tcpA. It was found that zot and ace genes in all strains, ctxA genes was found in 89/74 per cent and tcpA genes in 84.6 per cent of strains. It has been suggested that the control of cholera epidemics is too big a task for a national diarrheal diseases control programmed. Although this may be true in the case of extensive epidemics, it should not be forgotten that large outbreaks of this kind are often the result of initial delays in detection and containment. A properly organized national control programmed provides the framework for quick detection and prompt containment and is the best means of ensuring preparedness for cholera control

Equilibrium sorption of crude oil by expanded perlite using different adsorption isotherms at 298.15 k

During the past decades, a significant increase occurred in accidental oil spill in the aquatic environments. In this regard, oil spill in Marine freshwater is still considered as a major environmental hazard. In this research, the experimental data on the sorption capacity of expanded perlite to crude oil were correlated with the equilibrium isotherm of Langmuir, Freudlich, Tempkin and the three parameter Redlich-Peterson isotherms. The results obtained from each specified isotherms were compared and accuracy of the models were favorably discussed. Accuracy of each model using the error function were evaluated. Moreover, the effect of type of objective function on the final results was investigated. To bring up the idea; the sum of square of the average squares of the errors, the sum of the squares of the errors, the hybrid fractional error function, Marquardt&apos;s percent standard deviation and Chi-Square objective function were used and the accuracy was obtained using each objective function. The results showed that the Redlich-Peterson model can better represent the equilibrium isotherm data for the crude oil to be up taken on the expanded perlite

Efficacy of single-dose ceftriaxone versus multiple-dose enrofloxacin in dogs with uncomplicated lower urinary tract infection: A randomised clinical trial

WOS: 000396336300002eDogs with uncomplicated lower urinary tract infection (LUTI) are usually treated with appropriate antibiotics for 10-14 days. In humans, a single dose of ceftriaxone is employed in the treatment of uncomplicated LUTI. The purpose of the current study was to compare the efficacy of a single dose of ceftriaxone with multiple dose (14 days) enrofloxacin administration in dogs with uncomplicated LUTI. Forty-seven non-pregnant client-owned dogs with LUTI signs were enrolled in this prospective, controlled, randomised, blinded clinical trial. The inclusion criteria were the presence of at least one type of bacteria greater than or equal to 1000 CFU/ml in each urine sample. Dogs were assigned randomly to Group ENR (n = 23) enrofloxacin treatment (5 mg/kg, s.c., s.i.d., for 14 days) and Group CEF (n = 20) ceftriaxone treatment (25 mg/kg, i.v., once). The time needed for disappearance of clinical signs ranged from 4-9 days and 1-5 days for Group ENR and Group CEF, respectively. Clinical signs significantly improved earlier in Group CEF than in Group ENR (P < 0.0001). Urine culture with less than or equal to 1000 CFU/ml was achieved on Days 17-21 after the first day of treatment in all dogs. Although a single dose of ceftriaxone can be considered as an alternative treatment to alleviate the signs of uncomplicated LUTI in dogs, its status as drug of last resort is a limiting factor for its extensive use in clinical practice

Prevalence of depression in patients with cancer in Iran: A systematic review and meta-analysis

Introduction: It is generally accepted that depression, affecting the quality of life, is a serious and common complication in patients with cancer. Given that there is no integrated study on this topic in Iran, the present study sought to investigate the prevalence of depression in patients with cancer by a systematic review and meta-analysis. Methods: To meet the study objectives, all English and Persian papers published from 2000 to January 2018 were systematically collected and the data were extracted for analysis. Results: There were 14 studies which were selected on the basis of the inclusion and exclusion criteria. A total number of 2831 patients with cancer had participated in the studies. The prevalence of depression among Iranian patients with cancer was 35 (95 CI 16 to 70) based on random effects model. Among various types of cancer, the highest prevalence of depression appeared to patients suffering from breast cancer. Conclusion: The prevalence of depression among patients with cancer in Iran was higher than the developed countries. As depression affects the quality of life of patients with cancer, the results can help policymakers and service providers in planning to reduce the prevalence of depression. © Author(s) (or their employer(s)) 2019. No commercial re-use. See rights and permissions. Published by BMJ