390 research outputs found
Kinetic simulation of the sheath dynamics in the intermediate radio-frequency regime
The dynamics of temporally modulated plasma boundary sheaths is studied in
the intermediate radio frequency regime where the applied radio frequency and
the ion plasma frequency are comparable. Two kinetic simulation codes are
employed and their results are compared. The first code is a realization of the
well-known scheme, Particle-In-Cell with Monte Carlo collisions (PIC/MCC) and
simulates the entire discharge, a planar radio frequency capacitively coupled
plasma (RF-CCP) with an additional heating source. The second code is based on
the recently published scheme Ensemble-in-Spacetime (EST); it resolves only the
sheath and requires the time resolved voltage across and the ion flux into the
sheath as input. Ion inertia causes a temporal asymmetry (hysteresis) of the
sheath charge-voltage relation; also other ion transit time effects are found.
The two codes are in good agreement, both with respect to the spatial and
temporal dynamics of the sheath and with respect to the ion energy
distributions at the electrodes. It is concluded that the EST scheme may serve
as an efficient post-processor for fluid or global simulations and for
measurements: It can rapidly and accurately calculate ion distribution
functions even when no genuine kinetic information is available
On the identifiability of steady-state induction machine models using external measurements
A common practice in induction machine parameter identification techniques is to use external measurements of voltage, current, speed, and/or torque. Using this approach, it has been shown that it is possible to obtain an infinite number of mathematical solutions representing the machine parameters. This paper examines the identifiability of two commonly used induction machine models, namely the T-model (the conventional per phase equivalent circuit) and the inverse Γ-model. A novel approach based on the alternating conditional expectation (ACE) algorithm is employed here for the first time to study the identifiability of the two induction machine models. The results obtained from the proposed ACE algorithm show that the parameters of the commonly employed T-model are unidentifiable, unlike the parameters of the inverse Γ-model which are uniquely identifiable from external measurements. The identifiability analysis results are experimentally verified using the measured operating characteristics of a 1.1-kW three-phase induction machine in conjunction with the Levenberg-Marquardt algorithm, which is developed and applied here for this purpose
Molecular Characterization, Developmental Expression and Immunolocalization of Clathrin Heavy Chain in the Ovary of the American Cockroach, Periplaneta Americana During Oogenesis
Clathrin is the principal protein involved in receptor mediate endocytosis and the main component of the coated vesicles. It is composed of three identical clathrin heavy chains (CHC), each with an attached light chain. We characterized the deduced amino acid sequence of the partial cDNA clone of the American cockroach, Periplaneta americana (Pam) CHC. The analysis showed that this sequence is represented as multiple alpha helical repeats occurred in the arm region of the CHC and displayed a high level of identity and similarity to mosquitoes and Drosophila melanogaster CHCs. This is the first report on CHC from a hemimetabolous insect. The amplified CHC probe could hybridize two CHC transcripts in the current preparations, 6.3 kb and 7.3 kb. The Northern blot analysis confirmed that a 6.3 kb transcript is specifically expressed in ovarian tissues at high levels throughout the ovarian development, especially in previtellogenic ovaries (Days 1-4) but dropped during the vitellogenic period (days 5-7) and ultimately no transcript was detected in fully vitellogenic ovaries (days 9-13). Immunoblot analysis detected an ovary specific CHC protein of ~175 kDa that was present in previtellogenic ovaries on the day of female emergence and after initiation of vitellogenesis and onset of Vg uptake. Immunocytochemistry localized CHC protein to germ-line derived cells, oocytes, and revealed that CHC translation begins very early during oocyte differentiation in the germarium. The present work suggested a possible role for clathrin in the early fluid phase endocytosis (pinocytosis) in addition to its role in receptor-mediated endocytosis
The partially alternating ternary sum in an associative dialgebra
The alternating ternary sum in an associative algebra, , gives rise to the partially alternating ternary sum in an
associative dialgebra with products and by making the
argument the center of each term: . We use computer algebra to determine the polynomial identities in
degree satisfied by this new trilinear operation. In degrees 3 and 5 we
obtain and ; these identities define a new variety of partially alternating ternary
algebras. We show that there is a 49-dimensional space of multilinear
identities in degree 7, and we find equivalent nonlinear identities. We use the
representation theory of the symmetric group to show that there are no new
identities in degree 9.Comment: 14 page
Ligand-based design, synthesis, computational insights, and in vitro studies of novel N-(5-Nitrothiazol-2-yl)-carboxamido derivatives as potent inhibitors of SARS-CoV-2 main protease
The global outbreak of the COVID-19 pandemic provokes scientists to make a prompt development of new effective therapeutic interventions for the battle against SARS-CoV-2. A new series o
Efficacy and safety of Elagolix in the treatment of endometriosis associated pain: a systematic review and network meta-analysis
Background: Endometriosis commonly presents with dysmenorrhea, non-menstrual pelvic pain, and infertility. Elagolix is an oral, short-acting, gonadotropin-releasing hormone antagonist acting through complete estrogen suppression.
Objective: To evaluate the evidence from published randomized controlled trials (RCTs) about the efficacy and safety of Elagolix in the treatment of endometriosis associated pain.
Search strategy: Electronic databases containing articles published between January 2000 and February 2020 were searched using the MeSH terms (Elagolix OR gonadotropin-releasing hormone antagonist OR GnRH antagonist OR antigonadotropin) AND (endometriosis) AND (pelvic pain).
Selection criteria: All RCTs assessing the efficacy of Elagolix in the treatment of pain associated with endometriosis were considered for this network meta-analysis, where five studies were deemed eligible for this review.
Data collection and analysis: The mean difference (MD) and confidence intervals (95% CI) for continuous outcomes including analgesic use, dysmenorrhea, non-menstrual pelvic pain, and quality of life were calculated.
Main results: Elagolix 250 mg reduced dysmenorrhea significantly, as compared to placebo, (MD = -0.41, 95% CI [-0.7, -0.13]) at 12 weeks, while Elagolix 200 mg reduced dysmenorrhea significantly (MD= -1.2, 95% CI [-1.9, -0.57]) compared to placebo after 24 weeks of treatment.
Conclusions: Elagolix 200 mg seems to be an effective drug with fewer side effects when used to reduce dysmenorrhea and non-menstrual pelvic pain after 24 weeks of treatment in patients with endometriosis
Longitudinal transcriptomic and genetic landscape of radiotherapy response in canine melanoma
Canine malignant melanoma (MM) is a highly aggressive tumour with a low survival rate and represents an ideal spontaneous model for the human counterpart. Considerable progress has been recently obtained, but the therapeutic success for canine melanoma is still challenging. Little is known about the mechanisms beyond pathogenesis and melanoma development, and the molecular response to radiotherapy has never been explored before. A faster and deeper understanding of cancer mutational processes and developing mechanisms are now possible through next generation sequencing technologies. In this study, we matched whole exome and transcriptome sequencing in four dogs affected by MM at diagnosis and at disease progression to identify possible genetic mechanisms associated with therapy failure. According to previous studies, a genetic similarity between canine MM and its human counterpart was observed. Several somatic mutations were functionally related to MAPK, PI3K/AKT and p53 signalling pathways, but located in genes other than BRAF, RAS and KIT. At disease progression, several mutations were related to therapy effects. Natural killer cell-mediated cytotoxicity and several immune-system-related pathways resulted activated opening a new scenario on the microenvironment in this tumour. In conclusion, this study suggests a potential role of the immune system associated to radiotherapy in canine melanoma, but a larger sample size associated with functional studies are needed
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