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The purpose of this research is to provide a conceptual overview on published studies and articles related to social media and information systems as two independent, continuous and interdepend-ent concepts. The research data is from the survey for two social media keywords and information systems from the Scopus site, which is one of the main scientific search engines. Due to a large number of findings, the study area was limited to 6 major areas of social sciences, business management, economics, arts and humanities, psychology and decision-making sciences, and 5185 articles were found. To investigate and analyze the findings, the Romethometrics and bibliometrics library of R Studio software were used. Biblimetrix was a method for studying and evaluating quantitative scientific texts using mathematical and statistical methods. The data obtained from this research is useful for scholars, researchers, decision-makers and those interested in social media and information networks in the political, economic, social and cultural spheres.

Brucellosis is known as an important public health problem for humans around the world and is one of the most prevalent zoonotic disease as well. Brucella spp. is a Gram negative rod, facultative intracellular pathogenic and non motile bacteria. The aim of this study were to determine the frequency and biotyping of Brucella spp. isolated from sheep and goats from south eastern part of Iran. 700 samples (raw milk) from sheep and goats (90) flocks were collected randomly, from January to July 2015, samples were transferred packed in ice to microbiology lab in Kerman University, immediately. Samples were inoculated on Brucella agar which contains antibiotic and inactivated horse serum and incubate for 5 days. Gram smears were prepared from suspected colonies followed by oxidize and biochemical tests. Polymerase Chain Reaction (PCR) were used for confirmation. All positive samples were biotyped by phage typing. Nine milk samples out of 700 (1.28%) collected were positive by bacteriological method and all of them were Brucella melitensis Biotype 1 and one out of 700 samples was Brucella ovis. In relation to the National vaccination program in these areas the most contaminated region was Rabor, Rayen, Bardsir and Baft, respectively.

Ticks are obligatory bloodsucking arthropods, and probably the most harmful ectoparasites that may cause some tick born diseases. The main objective of this study was to determine the prevalence, diversity and seasonal distribution of ticks and using a nested Trans PCR to identify Coxiella burnetii in ticks collected from small ruminants in Sistan and Balouchestan province, southeast Iran. A total 1305 ticks were collected from 272 Sheep and 253 Goats during May 2014 to April 2015. Prevalence of ixodid tick infestation in small ruminants was 58.4%. Of all examined ticks, nine tick species were identified as follow: Hyalomma anatolicum anatolicum (30.3%), Rhipicephalus sanguineus (21%), Hyalomma anatolicum excavatum (19%), Rhipicephalus turanicus (9%), Rhipicephalus bursa (6.7%), Hyalomma detritum (4.7%), Hyalomma dromedarii (4.4%), Hyalomma asiaticum asiaticum (4.4%) and Hyalomma marginatum (0.5%). The nested Trans PCR examination of ixodid ticks revealed that Hyalomma anatolicum anatolicum and Rhipicephalus sanguineus were infected with C. burnetii. The results of the present study revealed that ixodid ticks infestation was widespread and shows their role as putative vectors and reservoirs for this pathogenic agent in southeast Iran. Hence; Q fever should be considered a significant public health threat in this region.

Two systems of polypropylene (PP), poly(lactic acid) (PLA) and ethylene vinyl alcohol copolymer (EVOH) ternary blends having different compositions were extruded in a co-rotating twin screw extruder. The first system was PP/PLA (75/25) with various EVOH contents, the second one was PP/EVOH (75/25) having various PLA contents. The effects of composition on the morphology and the tensile and impact properties of the blends were investigated. There were increases in the tensile modulus and tensile strength with an increase in the EVOH and PLA contents in the first and second systems, respectively. A molecular dynamics (MD) simulation was used to investigate the compatibility between the components. Prediction of the miscibility of the blends was carried out by determining the interaction parameters (χ), mixing energies (ΔHmix), phase diagrams and Gibbs free energies. The MD simulation showed a UCST behavior for the components. Moreover, the simulation results showed a compatibilizer effect for the EV...

AIMS Inappropriate use of antibiotics is one of the most important factors contributing to the emergence of drug resistant pathogens. The purpose of this study was to measure the clinical impact of antimicrobial stewardship programme (ASP) interventions on hospitalized patients at the Intensive care unit at Palestinian Medical Complex. METHODS A prospective audit with intervention and feedback by ASP team within 48-72 h of antibiotic administration began in September 2015. Four months of pre-ASP data were compared with 4 months of post-ASP data. Data collected included clinical and demographic data; use of antimicrobials measured by defined daily doses, duration of therapy, length of stay, readmission and all-cause mortality. RESULTS Overall, 176 interventions were made the ASP team with an average acceptance rate of 78.4%. The most accepted interventions were dose optimization (87.0%) followed by de-escalation based on culture results with an acceptance rate of 84.4%. ASP interventions significantly reduces antimicrobial use by 24.3% (87.3 defined daily doses/100 beds vs. 66.1 defined daily doses/100 beds P

Color is the most important characteristic of the ornamental fish. The use of pigments for changing the color of skin and carcasses has become more prominent in recent years. In the present study, the effects of astaxanthin pigment on skin color and tissue of parrotfish were studied using RGB and Lab techniques. Sixty parrotfish (with the average weight of 26.5±1.87 g) were distributed in different 50-liter volumetric aquariums (30×40×60 cm) and five dietary treatments with 3 replications for each treatment were considered. Treatments including the control (non-pigmented diet) and diets containing 0.2, 0.5, 1 and 1.5% of astaxanthin were prepared. After eight weeks of feeding fish with various treatments, four fish were taken from each treatment and their back muscles were used for the preparation of identical fillets. RGB and Lab techniques were used for the evaluation of the color of skin and muscle of fish. The results showed that change of color in the carcass texture in terms of the L component in all fish fed with the diets containing pigments were significantly decreased as compared to that of the control group (P

Measures of statistical divergence are used to assess mutual similarities between distributions of multiple variables through a variety of methodologies including Shannon entropy and Csiszar divergence. Modified measures of statistical divergence are introduced throughout the present article. Those modified measures are related to the Lin–Wong (LW) divergence applied on the past lifetime data. Accordingly, the relationship between Fisher information and the LW divergence measure was explored when applied on the past lifetime data. Throughout this study, a number of relations are proposed between various assessment methods which implement the Jensen–Shannon, Jeffreys, and Hellinger divergence measures. Also, relations between the LW measure and the Kullback–Leibler (KL) measures for past lifetime data were examined. Furthermore, the present study discusses the relationship between the proposed ordering scheme and the distance interval between LW and KL measures under certain conditions.

The dream of building machines that can do science has inspired scientists for decades. Remarkable advances have been made recently; however, we are still far from achieving this goal. In this paper, we review different machine learning techniques used in scientific discovery with their limitations. We survey and discuss the main principles driving the scientific discovery process. These principles are used in different fields and by different scientists to solve problems and discover new knowledge. We provide many examples of the use of these principles in different fields such as physics, mathematics, and biology. We also review AI systems that attempt to implement some of these principles. We argue that building science discovery machines should be guided by these principles as an alternative to the dominant approach of current AI systems that focuses on narrow objectives. Building machines that fully incorporate these principles in an automated way might open the doors for many advancements.

Морские водоросли вырабатывают вторичные метаболиты, обладающие антиоксидантной активностью и терапевтическим эффектом. Целью исследования было оценить антиоксидантную активность экстрактов этилацетата и метанола из трех видов водорослей: Nannochloropsis oculata (Droop) D.J. Hibberd, Enteromorpha sp., и Polysiphonia scopulorum Harvey. Marine algae produce secondary metabolites with antioxidant activity and therapeutic effects. The aim of this study was to evaluate the antioxidant activity of ethyl acetate and methanolic extracts of three algal species: Nannochloropsis oculata (Droop) D.J. Hibberd, Enteromorpha sp., and Polysiphonia scopulorum Harvey.

In the present work, impact of a Newtonian drop on horizontal thin fibers with circular cross section is simulated in 2D views. The numerical simulations of the phenomena are carried out using volume of fluid (VOF) method for tracking the free surface motion. Impacting of a Newtonian droplet on a circular thin fiber ( 350 μ m radius) investigated numerically. The main focus of this simulation is to acquire threshold radius and velocity of a drop which is entirely captured by the fiber. The model agrees well with the experiments and demonstrates the threshold radius decreased generally with the increase of impact velocity. In other words, for velocity larger than threshold velocity of capture perhaps only a small portion of fluid is stuck on the solid and the rest of the drop is ejected for impact velocity smaller than critical velocity the drop is totally captured. This threshold velocity has been determined when the impact is centered.

Thermal performance of a novel sintered wick heat pipe was investigated in this study. Two types of sintered wick heat pipes were fabricated and tested at different filling ratios of water, and their thermal resistances in different modes were compared. In the first type, wick was sintered annularly (conventional type), and in the other one (novel type of sintered wick) it was sintered only in one third of cross-section. Results showed that dry-out occurs at higher heat input by an increase in the filling ratio. Moreover, the best filling ratio is 20% for both heat pipes. Thermal resistances of the partly sintered wick heat pipe are approximately 28%, 17% and 47% lower than those of the annularly sintered one at 20% filling ratio in the vertical, horizontal and reverse-vertical modes, respectively. Gravity has a slight effect on partly sintered wick heat pipe performance in the horizontal mode. This novel type of sintered wick heat pipe has simpler structure, and its manufacturing is more affordable compared with the annularly sintered wick. Hence, the use of this type of novel heat pipe (partly sintered wick) rather than the conventional type (annularly sintered one) is recommended in most applications, especially in space conditions where the gravity is negligible. In addition, experimental results were compared with numerical ones, and it was shown that the Florez orthorhombic and Alexander models can provide reasonable predictions for the effective thermal conductivity of water-saturated sintered powder-metal wicks.

In this paper we use fractal method for detection and diagnosis of abnormalities in mammograms. We have used 168 images that were carefully selected by a radiologist and their abnormalities were also confirmed by biopsy. These images included asymmetric lesions, architectural distortion, normal tissue and mass lesion where in case of mass lesion they included circumscribed benign, ill-defined and spiculated malignant masses. At first, by using wavelet transform and piecewise linear coefficient mapping, image enhancement were done. Secondly detection of lesions was done by fractal method as a ROI. Since in investigation of breast cancer, it is important that fibroglandular tissues in both breasts be symmetric and for each asymmetric density, evaluation for malignancy is necessary, we define new fractal features based on extracting asymmetric information from lesions. The fractal features were evaluated on 5 data sets using SVM classifier which enabled to achieve high accuracy in classification of mammograms and diagnostic results. We have also investigated the performance of image enhancement in classification of each data set which shows different effects of enhancement on different lesion types.

This study was conducted with the aim of investigating phosphorus release from pomace or solid olive waste in the presence of phosphorus solubilizing Pseudomonas bacteria. A multi-level factorial experiment with complete randomized design was employed in three replications. A calcareous soil was mixed with 2 and 4 g pomace per 100 g soil (W2 and W4, respectively) and inoculated with indicator and soil isolated Pseudomonas sp. (106 cell g−1) (Pf and Pi, respectively). Soil without pomace and Pseudomonads were also included as control (W0Pn). Mixtures incubated in sterile and non-sterile conditions for 4 months. Sampling was carried out at 0, 2, 7, 14, 28, 42, 56, 86 and 120 days and some soil biochemical properties were measured. The effects of pomace, bacteria, incubation time and their interactions were significant on pH, EC, basal respiration, organic carbon (OC), available phosphorus (Pava) and phosphatase activity (p ≤ 0.01). Pomace increased soil OC content in both non-sterile and sterile conditions. The maximum amount of Pava in non-sterile mixtures was observed in W4Pi (133.25 mg kg−1). Pomace and phosphorus solubilizing bacteria addition to soil increased phosphatase activity. Although Pava concentration was highest in W4 treatments during the incubation period, its trend was ascending in W2 treatments. It seems that 2 g pomace per 100 g soil is enough for improving biological properties and phosphorus availability. Overall, the application of pomace with P-solubilizing bacteria can be a solution to increase soil available P level, reduce dependency on chemical P fertilizers and sustainable management of such solid wastes.

Hybrid-reinforced metals are novel composite materials in which nano-phases including nanoparticles and nanotubes/nanosheets are used simultaneously to reinforce metals or alloys to enhance physical, mechanical, wear and other properties. In this research, Cu/(CNT-SiC) hybrid nanocomposite was synthesized using flake powder metallurgy and spark plasma sintering method and the effects of hybrid reinforcements on microstructural, wear and corrosion properties of the developed material were investigated and compared with those of copper. Microstructural characterization showed reduction of average grain size from 419 to 307 nm and increase of low angle grain boundaries with the introduction and homogeneous dispersion of hybrid reinforcements. Mechanical tests indicated that the addition of hybrid SiC and CNT reinforcements substantially increased microhardness and reduced wear rate and friction coefficient of the Cu. Also, polarization and EIS tests revealed the suppressing of the anodic dissolution of the matrix, hindering the oxygen reduction reaction and 62.5% improvement of corrosion rate for the composite material. The effects of hybrid nano-reinforcements are presented and discussed.

The eye shape is of the most characteristics in the face and has been proven to have specific characteristics in some races. The aim of the current research is to study the gender and racial characteristics of the eye shape among the- Malaysian population (Malay/Chinese/Indian). This study included a total of 242 persons (121 males and 121 females) with age ranging from 18 to 40 years old, from the three main Malaysian races (Malay, Chinese and Indians (82, 80 and 80 respectively), without any craniofacial or oculofacial anomaly, disease or trauma. The eye width and intercanthal distance were measured to be used for determination of the shape of the eye. The studied measurements included interpupillary distance (IPD), inner intercanthal distance (ICD) and outer intercanthal distance (OCD). The mean measurements of OCD, ICD and IPD among Malaysian population are (89.06 mm, 85.89 mm), (32.27 mm, 31.25 mm) and (59.25 mm, 58.77 mm) in males and females respectively. There are significant intra-racial gender variations in the three Malaysian races in all measurements except the IPD that did not show significant gender variation. There are significant inter-racial gender variations in all measurements except the female IPD. It was concluded that in Malaysian races, the OCD and ICD are having significant inter-racial variation in both gender and also having a significant intra-racial gender variation while the IPD showed significant inter-racial variations only in males not in females and no intra-racial gender variation. These findings can be can be used for forensic identification purposes.