Detection of atrial fibrillation in ECG hand-held devices using a random forest classifier

Atrial Fibrillation (AF) is characterized by chaotic electrical impulses in the atria, which leads to irregular heartbeats and can develop blood clots and stroke. Therefore, early detection of AF is crucial for increasing the success rate of the treatment. This study is focused on detection of AF rhythm using hand-held ECG monitoring devices, in addition to three other classes: normal or sinus rhythm, other rhythms, and too noisy to analyze. The pipeline of the proposed method consists of three major components: preprocessing and feature extraction, feature selection, and classification. In total, 491 hand-crafted features are extracted. Then, 150 features are selected in a feature ranking procedure. The selected features are from time, frequency, time-frequency domains, and phase space reconstruction of the ECG signals. In the final stage, a random forest classifier is used to classify the selected features into one of the four aforementioned ECG classes. Using the scoring mechanism provided by PhysioNet/Computing in Cardiology (CinC) Challenge 2017, the overall score (mean±std) of 81.9±2.6% is achieved over the training dataset in 10-fold cross-validation. The proposed algorithm tied for the first place in the PhysioNet/CinC Challenge 2017 with an overall score of 82.6% (rounded to 83%) on the unseen test dataset.Scopu

The Association Between Personality Disorder Traits and Suicidality Following Sudden Bereavement: A National Cross-Sectional Survey

Personality disorder is associated with increased risk of suicidal behavior. The authors aimed to investigate the association between number of personality disorder traits and suicidality risk following sudden bereavement. A secondary analysis of cross-sectional data on 3,167 young adults in the United Kingdom who had experienced sudden bereavement investigated the association between number of traits (measured using a standardized screening instrument) and postbereavement suicide attempt and suicidal ideation. Using multivariable logistic regression, the authors found a linear relationship between number of traits and suicide attempt (adjusted odds ratio [AOR] = 1.36, 95% CI [1.23, 1.49]) and suicidal ideation (AOR = 1.31, 95% CI [1.25, 1.38]) following bereavement. This represented an increase in odds by 36% and 31%, respectively, for each additional personality trait. The authors suggest that individuals with a greater number of traits suggestive of a personality disorder diagnosis are at increased risk of suicidality after a negative life event

Multi-criteria decision making (MCDM) model for seismic vulnerability assessment (SVA) of urban residential buildings

© 2018 by the authors. Earthquakes are among the most catastrophic natural geo-hazards worldwide and endanger numerous lives annually. Therefore, it is vital to evaluate seismic vulnerability beforehand to decrease future fatalities. The aim of this research is to assess the seismic vulnerability of residential houses in an urban region on the basis of the Multi-Criteria Decision Making (MCDM) model, including the analytic hierarchy process (AHP) and geographical information system (GIS). Tabriz city located adjacent to the North Tabriz Fault (NTF) in North-West Iran was selected as a case study. The NTF is one of the major seismogenic faults in the north-western part of Iran. First, several parameters such as distance to fault, percent of slope, and geology layers were used to develop a geotechnical map. In addition, the structural construction materials, building materials, size of building blocks, quality of buildings and buildings-floors were used as key factors impacting on the building’s structural vulnerability in residential areas. Subsequently, the AHP technique was adopted to measure the priority ranking, criteria weight (layers), and alternatives (classes) of every criterion through pair-wise comparison at all levels. Lastly, the layers of geotechnical and spatial structures were superimposed to design the seismic vulnerability map of buildings in the residential area of Tabriz city. The results showed that South and Southeast areas of Tabriz city exhibit low to moderate vulnerability, while some regions of the north-eastern area are under severe vulnerability conditions. In conclusion, the suggested approach offers a practical and effective evaluation of Seismic Vulnerability Assessment (SVA) and provides valuable information that could assist urban planners during mitigation and preparatory phases of less examined areas in many other regions around the world

Heat induction in two-dimensional graphene–Fe3O4 nanohybrids for magnetic hyperthermia applications with artificial neural network modeling

We report the synthesis and characterization of graphene functionalized with iron (Fe3+) oxide (G-Fe3O4) nanohybrids for radio-frequency magnetic hyperthermia application. We adopted the wet chemical procedure, using various contents of Fe3O4 (magnetite) from 0–100% for making two-dimensional graphene–Fe3O4 nanohybrids. The homogeneous dispersal of Fe3O4 nanoparticles decorated on the graphene surface combined with their biocompatibility and high thermal conductivity make them an excellent material for magnetic hyperthermia. The morphological and magnetic properties of the nanohybrids were studied using scanning electron microscopy (SEM) and a vibrating sample magnetometer (VSM), respectively. The smart magnetic platforms were exposed to an alternating current (AC) magnetic field of 633 kHz and of strength 9.1 mT for studying their hyperthermic performance. The localized antitumor effects were investigated with artificial neural network modeling. A neural net time-series model was developed for the assessment of the best nanohybrid composition to serve the purpose with an accuracy close to 100%. Six Nonlinear Autoregressive with External Input (NARX) models were obtained, one for each of the components. The assessment of the accuracy of the predicted results has been done on the basis of Mean Squared Error (MSE). The highest Mean Squared Error value was obtained for the nanohybrid containing 45% magnetite and 55% graphene (F45G55) in the training phase i.e., 0.44703, which is where the model achieved optimal results after 71 epochs. The F45G55 nanohybrid was found to be the best for hyperthermia applications in low dosage with the highest specific absorption rate (SAR) and mean squared error values

Effect of artemia density on cyst yields of fertilized ponds

One of the effective factors in cyst production on Artemia culture ponds is the number of oviparous females and density of biomass in view of adult's weight per liter of ponds water. In this study, the effect of oviparous female's abundance (Reproductive Females lit^-1) on daily cyst yields with using the ANOVA and correlation Analytical method were assayed. The result indicated that, with presence the small number of oviparous females (less than five Ind lit^-1) and Artemia density (between 0/1 to 0/2g/ lit) on culture ponds, the cyst yields at first sixty days culture period (160 Kg.dw/ha) were more than yields that harvested at three months later (47 Kg.dw/ha) and on the second three months of cultural period despite of presence the larger number of oviparous females (more than twenty Ind/lit) and presence the same Artemia population density, the daily cyst yields was declined.(Sig=0.000)

Study on feasibility of rearing integrated native fish of Shizotorax zarudnyi with chianies carp on Sistan area

Present study carried out in 6 earthen ponds (3500 m^2 each) at the Zahak fish propagation and cultivation center. In July 2005 ponds were prepared and stocked with 1100 fish specimens with 40 g average weight. Stocking normative in two ponds (1 and 4) were 220 common carp, 110 grass carp, 715 silver carp, and 55 big head specimens. In the next two ponds (5 and 6) common carp reduced to 50% and Shizotorax zarudnyi was replaced. In the rest two ponds (7 and 8) common carp reduced to zero and totally replaced with Shizotorax zarudnyi. Manure and inorganic fertilizer were used during cultivation period. Carp was fed by concentrated food and grass carp was fed by alfalfa. At the end of the cultivation period (16 months) mean weights of common carp, grass carp, silver carp, big head, and Shizotorax zarudnyi reached 1201 g, 1572 g, 313 g, 486 g, 531 g respectively. Mean daily growth were 2.41 g, 3.19 g, 0.56 g, 0.92 g, 1 g respectively. Survival rate during cultivation period were 97.57%, 68.3%, 94%, 85.45%, 46.85% respectively. Biological parameters were recorded once a month. Other chemical and physical parameters such as air and water temperatures, oxygen, pH, twice per day and factors such as nitrite, nitrate, Ammoniac, transparency, salinity and phosphate were measured and recorded once per week. During cultivation period average pH was 7-10.34, water temperature was 0.5-33 °C, transparency was 12-115cm, salinity was 1.1-5 mg/l, oxygen was 2-10 mg/l, nitrite was 0.86-0.16 mg/l, nitrate was 0.06- 2.21 mg/l, and phosphate was 0.1-1.8 mg/l. Average total yields in the ponds 1 and 4 with standard normative for the region were 554, and 623 kg. In the ponds 5 and 6 with 50% Shizotorax zarudnyi were 514 and 518 kg, and in the ponds 7 and 8 with total Shizotorax zarudnyi replacement were 533 and 386 kg

Evaluation silo (Cylindrical) fish tanks as an applicable method for aquaculture of rainbow trout (Oncorhynchus mykiss)

This investigation conducted for evaluation Silo (Cylindrical) Fish Tanks as an applicable method for aquaculture of Rainbow trout (Oncorhynchus mykiss). Current research was designed in two practical phases as accidental experiments through 3 treatments and repeats of which stocked by three Rainbow trout (375 gr) densities as 75, 100 and 125 fish/m^3 in 9 silo fish tanks (2 m^3). For better understandings of the silo performance method, concrete circular fish tanks (similar volume) considered as controls and stocked as similar fish densities as silo tanks. The duration of the first phase of experiment was 150 days. The second phase of the experiment was determined for evaluating two proposed silo type (Inlet and outlet in bottom side / Inlet from bottom and outlet in upper side). In this stage, proposed silos (stocked by fish of 294 gr weigh) tested for rearing trout for 30 days. Water supplied from two surface wells after some aeration operations. Stocked fish were fed by pellets made by Fish Feed Chineh Company (Ltd) in Iran. Feeding operation conducted according to the recognized manuals by consideration of water temperature, fish weight and biomass. Meanwhile, biometry operation conducted in 10 days intervals while fish were anaesthetized. In addition, water quality was determined by daily measurements. According to the results of the first phase of experiment, there were significant variations on Growth rate, survival rate, FCR, FCE and SGR through the cultured organisms in silo tanks compared to the circular tanks. Meanwhile, according the results of an economic study on this survey, the fish culture in silo tanks showed significant economical and profitable in compare to controls. In additions, the second phase of experiment showed better aeration conditions in silo tanks when inlet water supply from bottom side and outlet located in upper side. Because of the fine distribution of fish in silo tanks and more usage of depth by this method, fish culture would be an applicable and profitable technique in narrow lands and slopes through the mountains area. The maximum stocking rate recorded more than 100 Kg fish/m^3 in silo tanks

An insight into the effect of rough surfaces and contact orientation on the fretting characteristics of quenched and tempered steel

The effect of a rough, textured surface and contact orientations on the fretting behavior of self-mated martensitic 34CrNiMo6 +QT steel was examined via a large annular flat-on-flat contact. A friction study accompanied by microscopy analyses was performed to provide a clear insight into fretting characteristics. In gross sliding, the rough surface revealed a lower delayed friction peak and the same steady-state friction as the fine-ground smooth one. In partial slip, the stable friction threshold was around 0.5 for both surfaces. The oxidation-abrasion and its combination with adhesion were observed as wear mechanisms in partial slip and gross sliding, respectively.Peer reviewe

Sperm bank creation of Caspian Sea trout (Salmo trutta caspius) breeders

The Caspian Sea trout (Salmo trutta caspius) is distributed in southern basin of the sea and the natural stocks of this fish is critically endangered. The present study was conducted through the breeding seasons of Caspian Sea trout in January 2012. Estimation of sperm male potential was carried on samples collected from a total of 12 male spawners which included 8 samples (caught 3 years ago) and 4 samples (freshly caught). Semen samples were collected after anesthetized with clove powder for 10 minutes at water temperature of 9-9.4 °C. The differences of mean semen volumes, sperm motility time, sperm density and the percentage of sperm motility from freshly caught spawners (5.5±3.4 ml, 35.5±8.7 sec, 4.3±0.7×109 ml^-1, 32.5 ± 8.5% respectively) were significantly higher than 3 years caught spawners (1.5±0.93 ml, 26.5± 2.8 sec, 1.98±1.6×109 ml^-1, 25.7±9.7 % respectively) (P0.05)