The use of computed tomography (CT) scan is essential for making diagnoses for trauma patients in emergency medicine. Numerous studies have been conducted on guiding medical examinations in light of ...advances in machine learning, leading to more accurate and rapid diagnoses. The present study aims to propose a machine learning-based method to help emergency physicians prevent performance of unnecessary CT scans for chest trauma patients.
A dataset of 1000 samples collected in nearly two years was used. Classification methods used for modeling included the support vector machine (SVM), logistic regression, Naïve Bayes, decision tree, multilayer perceptron (four hidden layers), random forest, and K nearest neighbor (KNN). The present work employs the decision tree approach (the most interpretable machine learning approach) as the final method.
The accuracy of 7 machine learning algorithms was investigated. The decision tree algorithm was of higher accuracy than other algorithms. The optimal tree depth of 7 was chosen using the training data. The accuracy, sensitivity and specificity of the final model was calculated to be 99.91% (95%CI: 99.10% - 100%), 100% (95%CI: 99.89% - 100%), and 99.33% (95%CI: 99.10% - 99.56%), respectively.
Considering its high sensitivity, the proposed model seems to be sufficiently reliable for determining the need for performing a CT scan.
The object of this research is to compare the behavior of floating and end bearing stone columns made of recycled aggregates of building debris with natural aggregate. To do so, both types of stone ...columns were constructed by crushed concrete and crushed brick as recycled aggregates and compared with the same models made of gravel as natural aggregates. All the columns were constructed with the same size, density, and grading in a clay bed. To evaluate the initial quality of materials of the stone columns, the index tests were performed. The results of such tests illustrated the less resistance of recycled materials in comparison to the natural materials; On the contrary, according to the results of the index tests, crushed bricks are not recommended to construct stone columns. Despite the index tests, results of loading on a floating column filed with natural and recycled aggregate were approximately the same, but the bearing capacity of the end bearing column made of natural aggregates was higher than the same model made of recycled aggregates.
The cryopreservation of spermatozoa was introduced in the 1960s as a route to fertility preservation. Despite the extensive progress that has been made in this field, the biological and biochemical ...mechanisms involved in cryopreservation have not been thoroughly elucidated to date. Various factors during the freezing process, including sudden temperature changes, ice formation and osmotic stress, have been proposed as reasons for poor sperm quality post-thaw. Little is known regarding the new aspects of sperm cryobiology, such as epigenetic and proteomic modulation of sperm and trans-generational effects of sperm freezing. This article reviews recent reports on molecular and cellular modifications of spermatozoa during cryopreservation in order to collate the existing understanding in this field. The aim is to discuss current freezing techniques and novel strategies that have been developed for sperm protection against cryo-damage, as well as evaluating the probable effects of sperm freezing on offspring health.
Avian spermatozoa are highly susceptible to reactive oxygen species (ROS) produced during the cryopreservation. The aim of the current study was to investigate the antioxidant effects of resveratrol ...(RSV) during rooster semen cryopreservation. Changes in expression of AMP-activated protein kinase as a possible mechanism behind the beneficial effects of resveratrol were also evaluated. Semen samples were collected from ten Ross broiler breeders (52-wk) using abdominal massage, then divided into 4 equal aliquots and cryopreserved in Beltsville extender that contained different concentrations (0 µM, 0.01µM, 0.1µM, and 1µM) of RSV. higher percentage (P < 0.05) of total motility and membrane integrity was observed in RSV-0.1 compared to the other frozen groups. Moreover, higher percentage of sperm mitochondrial activity was observed in the RSV-0.01 and RSV-0.1 compared to the frozen control (P < 0.05). The lowest percentage of apoptotic like changes was found in the RSV-0.1 in comparison to the other groups (P < 0.05). RSV-0.01 and RSV-1 groups produced the lowest levels of H2O2 and O2− compared to the other frozen groups, respectively. Malondialdehyde (MDA) concentration, velocity average path (VAP), and linearity (LIN) were not affected by different concentrations of RSV (P > 0.05). We observed a dose-dependent increase in AMP-activated protein kinase expression in groups exposed to RSV. Thus, RSV-1 increased AMP-activated protein kinase phosphorylation but had no positive effects on post thaw sperm parameters. Our findings suggest that RSV-0.1 improve thawed sperm functions, and these effects might be mediated through activation of AMP-activated protein kinase.
The protection of human sperm during cryopreservation is of great importance to infertility. Recent studies have shown that this area is still a long way from its ultimate aim of maintaining the ...maximum viability of sperm in cryopreservation. The present study used trehalose and gentiobiose to prepare the human sperm freezing medium during the freezing-thawing. The freezing medium of sperm was prepared with these sugars, and the sperm were then cryopreserved. The viable cells, sperm motility parameters, sperm morphology, membrane integrity, apoptosis, acrosome integrity, DNA fragmentation, mitochondrial membrane potential, reactive oxygen radicals, and malondialdehyde concentration was evaluated using standard protocols. A higher percentage of the total and progressive motility, rate of viable sperm, cell membrane integrity, DNA and acrosome integrity, and mitochondrial membrane potential were observed in the two frozen treatment groups compared to the frozen control. The cells had less abnormal morphology due to treatment with the new freezing medium than the frozen control. The higher malondialdehyde and DNA fragmentation were significantly observed in the two frozen treatment groups than in the frozen control. According to the results of this study, the use of trehalose and gentiobiose in the sperm freezing medium is a suitable strategy for sperm freezing to improve its motion and cellular parameters.
Although semen cryopreservation is an important, widely used technique for long-term sperm storage, it not only induces partially irreversible damages to sperm but might also deteriorate anatomical, ...biochemical, and structural organelles. These cellular and epigenetic modifications are the main reasons underlying the decline in sperm motility and fertility during the freeze-thaw process. Using the two Lake and Beltsville semen extenders, the present study aims to evaluate the epigenetic patterns (DNA methylation and histone modification), cellular parameters (e.g., membrane integrity, viability, DNA stability, mitochondria activity, and apoptosis status), and fertility potential of rooster semen collected from six mature roosters before and after cryopreservation according to a standard protocol. The results show that cryopreservation leads to significantly (P < 0.05) reduced values of the parameters examined when compared with those of fresh sperms. While the extenders used exhibit no difference with respect to DNA methylation (DNMT), the Lake extender leads to significant reductions (P < 0.05) in H3K9 acetylation (17.4 ± 1.8) and H3K4 methylation (42 ± 2.3) compared to the Beltsville (9.2 ± 1.8 and 23 ± 2.3, respectively). Compared to the Beltsville extender, the Lake one is also observed to yield a significantly (P < 0.05) superior sperm quality in terms of total motility (TM; 77.2 ± 1.6 vs. 68.3 ± 1.6), average path velocity (VAP; 71 ± 1.4 vs. 53 ± 1.4), and straight-line velocity (VSL; 52 ± 1.5 vs. 34 ± 1.5) as well as significantly (P < 0.05) higher viability (60 ± 1.69 vs. 51 ± 1.69) and membrane functionality (55 ± 3.2 vs. 46 ± 3.2). The Lake extender is also found to outperform the Beltsville one due to its significantly (P < 0.05) higher fertility rate (59.5% vs. 47.2%). The two extenders, however, exhibit no differences in DNA fragmentation, mitochondrial activity, or hatchability rate. The Beltsville extender showed to be superior to the Lake one due to its significantly greater reactive oxygen species percentage (ROS; 45.9 ±.3.2 vs. 28.5 ± 3.2) and apoptosis (29 ± 2.3 vs. 27 ± 2.3). It may be concluded that the Lake extender is capable of improving the cellular and epigenetic parameters of rooster sperms during cryopreservation due to the crucial roles it plays in the protection of sperms against cryo-damages.
•Semen was cryopreserved in Lake and Beltsville Extenders.•Epigenetic patterns of sperm was changed post thawing.•Lake had the lower histone modifications rather than Beltsville.•The higher quality of post-thaw semen was obtained in Lake.
Reduction in weight and energy consumption is among the most concerning subjects in the automotive industry. To date, advanced high-strength steel (AHSS) has been one of the best solutions to reach ...this objective. However, this material involves high chemical composition and production processing costs. This paper introduces a new grade of third-generation medium Mn AHSS with extraordinary mechanical properties. Regarding its product of strength and elongation (PSE), i.e., 86 GPa%, this is the highest value of PSE of an AHSS reported until now to the best of the author's knowledge. Also, because of using 13 wt% of Mn, lower Mn has been used than conventional twinning-induced plasticity (TWIP) steels, and mechanical properties have been improved. The samples were fabricated using a vacuum induction furnace (VIM) and heat-treated at four different temperatures to perform austenite reversion transformation (ART). The best sample (i.e., the one with the highest PSE) was microstructurally evaluated and compared to the as-rolled one. In addition, the effect of different heat treatment temperatures on mechanical properties was observed. The difference in mechanical properties is mainly related to different austenite stabilities and fractions. Intercritical annealing formed lamellar austenite layers with varying levels of stability. These layers caused the TRIP to stay active during the whole deformation process. Since this structure can also delay necking, high elongation was achieved along with high strength.
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Three different solidification routes (slow, accelerated and fast) and a two-step heat treatment process were applied to a FeCrNiBSi alloy system to introduce new candidates for ...advanced high-strength steels (AHSSs). The evolution of the microstructure after hot roll, heat treatment, and tensile deformation was characterized using optical and electron microscopy techniques, as well as hardness and room temperature uniaxial tensile tests. The increase in the initial strain-hardening rate (strain incompatibility of microstructure components) due to grain refinement as a consequence of fast casting cooling rate results in higher mechanical properties in fast-cooling specimens with a formability index of 18.00–37.80 GPa%. Deformation-induced precipitation in the as-rolled fast-cooling specimen and transformation-induced plasticity, microband formation, and austenite grain rotation in the heat-treated fast-cooling specimen are the main dissipation energy mechanisms. The heat-treated accelerated-cooling and slow-cooling specimens with formability index of 4.75–25.50 and 2.34–14.60 GPa%, respectively, are competitive with transformation-induced plasticity, dual-phase, and complex-phase AHSSs.
Cryopreservation is a way to preserve germplasm with applications in agriculture, biotechnology, and conservation of endangered animals. Cryopreservation has been available for over a century, yet, ...using current methods, only around 50% of spermatozoa retain their viability after cryopreservation. This loss is associated with damage to different sperm components including the plasma membrane, nucleus, mitochondria, proteins, mRNAs, and microRNAs. To mitigate this damage, conventional strategies use chemical additives that include classical cryoprotectants such as glycerol, as well as antioxidants, fatty acids, sugars, amino acids, and membrane stabilizers. However, clearly current protocols do not prevent all damage. This may be due to the imperfect function of antioxidants and the probable conversion of media components to more toxic forms during cryopreservation.
ABSTRACT
An excessive amount of aromatase enzyme reduces reproductive performance in aging roosters. Testosterone metabolism by aromatase enzyme is one of the reasons for reduced testosterone and ...lower fertility of aging roosters. The purpose of this study was to determine the effects of Exemestane (EX), as a steroidal aromatase inhibitor, on the seminal parameters and reproductive hormones of aging roosters. A total of 20 roosters (45 wk of age) were housed in individual cages and received a standard basal diet and oral EX capsules for 60 D at the daily doses per rooster (mg/rooster) in the following experimental groups: 0 mg (CTRL), 0.25 mg (Ex-0.25), 0.5 mg (Ex-0.5), and 1.5 mg (Ex-1.5). Sperm samples were obtained on days 1, 20, 40, and 60 of experiment. Blood samples were taken on days 1 and 60. The results indicated that different EX dosages affected semen parameters (P < 0.05) other than semen volume, morphology, apoptosis, and acrosome integrity. Various semen characteristics were significant (P < 0.05) during different times of the experiment, with the exception of semen volume, total motility, membrane integrity, morphology, apoptosis, and acrosome integrity. Roosters that received 0.5 mg of EX had higher percentages of sperm concentration, total motility, progressive motility, membrane integrity, viability, and mitochondrial activity (P < 0.05). There were lower concentrations of malondialdehyde in the CTRL (0 mg) and Ex-0.25 groups (P < 0.05). Although there was no significant difference in hormones at day 0 of the experiment (P > 0.05), roosters in the Ex-0.5 had higher concentration of testosterone as well as lower of aromatase activity at day 60 (P < 0.05). It can be concluded that EX improved semen parameters and testosterone, which ultimately can increase fertility in the aging broiler breeder roosters.
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