200 research outputs found
Photooxidative Removal of p-Nitrophenol by UV/H2O2 Process in a Spinning Disk Photoreactor: Influence of Operating Parameters
In this paper, spinning disk photoreactor (SDP) has been used for the removal of a refractory pollutant, namely p-nitrophenol (PNP), in UV/H2O2 process. The effect of various parameters such as the plate type in the SDP, concentration of oxidant (H2O2), fluid volume, initial concentration of PNP, distance of the lamps from the spinning disk, distance of the lamps from each other, pH, and rotation speed of the spinning disk in the removal efficiency has been investigated. The results indicated that the use of scrobiculate disc instead of flat disc significantly increased the removal percentage of PNP from 46 to 100 % for the irradiation time of 20 min; it also increased with increasing H2O2 concentration, but the increase in fluid volume and the initial concentration of PNP reduced the removal percentage of PNP in the SDP. The increase in the distance of UV lamps from each other and from disc surface in the SDP reduced the removal percentage of PNP. However, the increase in pH to 5.5 increased removal efficiency while increasing pH above 5.5 reduced PNP removal efficiency. The disk rotation speed from 0 to 90 rpm increased the removal percentage from 49 to 70 % for the irradiation time of 5 min, but increasing the rotation speed to more than 90 rpm reduced the removal efficiency.
This work is licensed under a Creative Commons Attribution 4.0 International License
Use of HPC to Analyze Changes in Gene Expression during Fruit Fly Spermiogenesis
In the fruit fly, Drosophila melanogaster, JAK/STAT signaling during spermiogenesis is known to play a crucial role in the maintenance of stem cells of the testis. Recent studies in our lab have shown that activation of the JAK/STAT pathway in somatic cyst cells is also required for the later stages of spermiogenesis like individualization.
The main goal of this project is to characterize the events downstream of JAK/STAT signaling in spermiogenesis and more specifically to determine the mechanism by which JAK/STAT activation regulates individualization, a later stage in spermiogenesis where 64 individual spermatids are formed from a 64-interconnected spermatid bundle.
This study has compared transcriptional profiles of testes in which JAK/STAT signaling has been genetically arrested prior to individualization to testes from wild type flies using RNA-seq methods
Sol–Gel Synthesis of Iron-Doped Sepiolite as a Novel Humidity-Sensing Material
Nowadays, humidity sensors are attracting a great deal of attention, and there are many studies focusing on enhancing their performances. Nevertheless, their fabrication through facile methods at reasonable cost is a significant factor. In this article, a new magnesium silicate nanopowder was successfully synthesized using a simple and low-cost sol–gel method. Subsequently, modified sepiolite was achieved by the substitution of iron ions in the synthesized nanopowders. The specimens were then characterized by X-ray diffraction, field emission–scanning electron microscopy, X-ray photoelectron spectroscopy, thermogravimetric–differential thermal analysis, infrared spectroscopy, and nitrogen adsorption. Furthermore, humidity sensors were manufactured by screen printing the prepared powders on alumina substrates with interdigitated Pt electrodes. The results showed that the fabricated sensors with modified sepiolite exhibited interesting characteristics for humidity detection
Fabrication and characterization of the modified ev31-based metal matrix nanocomposites
Metal matrix nanocomposites (MMNCs) with high specific strength have been of interest for numerous researchers. In the current study, Mg matrix nanocomposites reinforced with AlN nanoparticles were produced using the mechanical stirring-assisted casting method. Microstructure, hardness, physical, thermal and electrical properties of the produced composites were characterized in this work. According to the microstructural evaluations, the ceramic nanoparticles were uniformly dispersed within the matrix by applying a mechanical stirring. At higher AlN contents, however, some agglomerates were observed as a consequence of a particle-pushing mechanism during the solidification. Microhardness results showed a slight improvement in the mechanical strength of the nanocomposites following the addition of AlN nanoparticles. Interestingly, nanocomposite samples were featured with higher electrical and thermal conductivities, which can be attributed to the structural effect of nanoparticles within the matrix. Moreover, thermal expansion analysis of the nanocomposites indicated that the presence of nanoparticles lowered the Coefficient of Thermal Expansion (CTE) in the case of nanocomposites. All in all, this combination of properties, including high mechanical strength, thermal and electrical conductivity, together with low CTE, make these new nanocomposites very promising materials for electro packaging applications
Improving Decision Support Systems with Machine Learning: Identifying Barriers to Adoption
Precision agriculture (PA) has been defined as a “management strategy that gathers, processes and analyzes temporal, spatial and individual data and combines it with other information to support management decisions according to estimated variability for improved resource use efficiency, productivity, quality, profitability and sustainability of agricultural production.” This definition suggests that because PA should simultaneously increase food production and reduce the environmental footprint, the barriers to adoption of PA should be explored. These barriers include: 1) the financial constraints associated with adopting DSS, 2) the hesitancy of farmers to change from their trusted advisor to a computer program often behaves as a black box, 3) questions about data ownership and privacy, and 4) the lack of a trained workforce to provide the necessary training to implement DSSs on individual farms. This paper also discusses the lessons learned from successful and unsuccessful efforts to implement DSSs, the importance of communication with end-users during DSS development, and potential career opportunities that DSSs are creating in PA
Coherent State for a Relativistic Spinless Particle
The Klein-Gordon equation with scalar potential is considered. In the
Feshbach-Villars representation the annihilation operator for a linear
potential is defined and its eigenstates are obtained. Although the energy
levels in this case are not equally-spaced, depending on the eigenvalues of the
annihilation operator, the states are nearly coherent and squeezed. The
relativistic Poschl-Teller potential is introduced. It is shown that its energy
levels are equally-spaced. The coherence of time evolution of the eigenstates
of the annihilation operator for this potential is evaluated.Comment: 12 pages, 11 figures, to appear in Phys. lett.
How Can We Identify Hijacked Journals?
By developing research and academic centers, the number of performed research articles has also increased. On the other hand, publishing the results of these articles in scientific journals shall also grow. In the meantime, researchers are trying to publish the findings of their research in journals which have been approved by one or more International indices so that such findings can be seen. In order to enhance the academic standards of Universities, proper journal choice will be of interest to researchers, especially those that are indexed in websites such as Thomson Reuters. However, certain forgery frauds researchers by launching fake Web sites that have been named by academic journal titles. In this paper, we introduce an approach to identify this type of journals that will be applicable by researchers in various academic disciplines
Promoting C–C Bond Coupling of Benzyne and Methyl Ligands in Electron-Deficient (triphos)Pt–CH 3 + Complexes
In situ generated benzyne reacts at room temperature with (triphos)Pt-CH3 (+) to form a five-coordinate π-complex (2) that is isolable and stable in solution. Thermolysis of 2 at 60 °C generates (triphos)Pt(o-tolyl)(+) (3), which is the product of formal migratory insertion of CH3 (-) onto the coordinated benzyne. The reaction of 2 with the acid Ph2NH2 (+) yields toluene at room temperature over the course of 8 h, while the same reaction with 3 only proceeds to 40% conversion over 2 days. These data indicate that the protonolysis of 2 does not proceed by CH3 migration onto benzyne to form 3 followed by protodemetalation. Instead, the data suggest either that protonation of 2 is first and is followed by H migration to yield a Pt(IV)Ph(Me) dication or that this latter species is generated by direct protonolysis of coordinated benzyne prior to reductive elimination of toluene
Negative Effects of “Predatory” Journals on Global Health Research
Se analiza el efecto perjudicial que ocasionan en la investigación en salud las revistas conocidas como "Depredadoras".Predatory journals (PJ) exploit the open-access model promising high acceptance rate and fast track publishing without proper peer review. At minimum, PJ are eroding the credibility of the scientific literature in the health sciences as they actually boost the propagation of errors. In this article, we identify issues with PJ and provide several responses, from international and interdisciplinary perspectives in health sciences. Authors, particularly researchers with limited previous experience with international publications, need to be careful when considering potential journals for submission, due to the current existence of large numbers of PJ. Universities around the world, particularly in developing countries, might develop strategies to discourage their researchers from submitting manuscripts to PJ or serving as members of their editorial committees
Relationship between the severity of endometriosis symptoms (dyspareunia, dysmenorrhea and chronic pelvic pain) and the spread of the disease on ultrasound
Objectives: About 10�15 of women of childbearing age have endometriosis. The present study aimed to investigate the relationship between the severity of symptoms of endometriosis and the spread as well as the stage of the disease on ultrasonography. The present cross-sectional study evaluates the relationship between the severity of endometriosis symptoms and the spread of disease on ultrasonography in patients with endometriosis. Results: Considering different analyses, the cumulative size of posterior deep infiltrative endometriosis (DIE) (less than 1 cm) is significantly correlated with minimal severity of dyspareunia and chronic pelvic pain. The incidence of dyspareunia was more prevalent in patients with complete stenosis of Douglas pouch than those with incomplete stenosis. Furthermore, the incidence of severe and very severe pain in patients with Douglas pouch stenosis is relatively higher than that in patients without stenosis. Only dyspareunia is related to the stage of endometriosis, and patients with dyspareunia are five times more at risk of a higher stage of the disease. The severity of dyspareunia is related to the stage of endometriosis and the severity of Douglas pouch stenosis. The results showed a correlation between chronic pelvic pain and r-ASRM score (revised American Society for Reproductive Medicine score). © 2020, The Author(s)
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