207 research outputs found
In vitro antiviral effects of Peganum harmala seed extract and its total alkaloids against Influenza virus
This research was aimed to evaluate the in vitro antiviral effect and the mechanism of the effect of
Peganum. harmala seeds extract against influenza A virus infection using Madin-Darby canine kidney
(MDCK) cells. In this research, ethyl alcohol extract of P. harmala seeds and its total alkaloids was prepared.
The potential antiviral activity of the extract and its total alkaloids against influenza A/Puerto Rico/
8/34 (H1N1; PR8) virus was assessed. The mode of action of the extract to inhibit influenza replication
was investigated using virucidal activity, hemagglutination inhibition assay, time of addition assays, RNA
replication, western blot analysis and RNA polymerase blocking assay. The crud extract of P. harmala seed
and its total alkaloids showed the best inhibitory effect against influenza A virus replication in MDCK
cells using MTT assay, TCID50 method and hemagglutination assay. Our results indicated that the extract
inhibits viral RNA replication and viral polymerase activity but did not effect on hemagglutination inhibition
and virucidal activity. This study showed that, in vitro antiviral activity of P. harmala seed extract
against influenza virus is most probably associated with inhibiting viral RNA transcription. Therefore, this
extract and its total alkaloid should be further characterized to be developed as anti-influenza A virus
agent
Comparing the effect of Toll-like receptor agonist adjuvants on the efficiency of a DNA vaccine
We have investigated whether poly(I:C) Toll-like receptor 3 (TLR3) and resiquimod Toll-like receptor 7 (TLR7) agonists can serve as vaccine adjuvants and promote the efficiency of therapeutic DNA vaccination against tumors expressing the human papilloma virus 16 (HPV-16) E7 protein. For this purpose, C57BL/6 mice were inoculated with 2 × 105 TC-1 cells, and they were then immunized with HPV-16 E7 DNA vaccine alone or with 50 μg of resiquimod or poly(I:C) individually. We found that poly(I:C) and resiquimod could induce more antigen-specific lymphocyte proliferation and cytolytic activity compared to vaccination with E7 DNA alone. While E7 DNA had no significant inhibitory effect on tumor growth, co-administration of poly(I:C) and resiquimod with E7 DNA induced significant tumor regression. Peripheral and local cytokine assays demonstrated that co-administration of poly(I:C) and resiquimod with E7 DNA induced circulating antigen-specific IFN-γ and nonspecific intratumoral IL-12. TLR3 and TLR7 agonists can be used to enhance the immune response to DNA vaccine immunogens. Taken together, these data indicate that combined vaccination with DNA encoding HPV-16 E7 plus TLR agonists provides a strategy for improving the efficacy of a vaccine as a possible immunotherapeutic strategy for cervical cancer. © 2014 Springer-Verlag Wien
Local Electricity Markets for Electric Vehicles: An Application Study Using a Decentralized Iterative Approach
Local electricity markets are emerging solutions to enable local energy trade for the end users and provide grid support services when required. Various models of local electricity markets (LEMs) have been proposed in the literature. The peer-to-peer market model appears as a promising structure among the proposed models. The peer-to-peer market structure enables electricity transactions between the players in a local energy system at a lower cost. It promotes the production from the small low–carbon generation technologies. Energy communities can be the ideal place to implement local electricity markets as they are designed to allow for larger growth of renewable energy and electric vehicles, while benefiting from local transactions. In this context, a LEM model is proposed considering an energy community with high penetration of electric vehicles in which prosumer-to-vehicle (P2V) transactions are possible. Each member of the energy community can buy electricity from the retailer or other members and sell electricity. The problem is modeled as a mixed-integer linear programing (MILP) formulation and solved within a decentralized and iterative process. The decentralized implementation provides acceptable solutions with a reasonable execution time, while the centralized implementation usually gives an optimal solution at the expense of reduced scalability. Preliminary results indicate that there are advantages for EVs as participants of the LEM, and the proposed implementation ensures an optimal solution in an acceptable execution time. Moreover, P2V transactions benefit the local distribution grid and the energy community
Local Electricity Markets for Electric Vehicles: An Application Study Using a Decentralized Iterative Approach
Local electricity markets are emerging solutions to enable local energy trade for the end
users and provide grid support services when required. Various models of local electricity
markets (LEMs) have been proposed in the literature. The peer-to-peer market model appears
as a promising structure among the proposed models. The peer-to-peer market structure
enables electricity transactions between the players in a local energy system at a lower cost. It
promotes the production from the small low–carbon generation technologies. Energy
communities can be the ideal place to implement local electricity markets as they are
designed to allow for larger growth of renewable energy and electric vehicles, while
benefiting from local transactions. In this context, a LEM model is proposed considering
an energy community with high penetration of electric vehicles in which prosumer-to-vehicle
(P2V) transactions are possible. Each member of the energy community can buy electricity from
the retailer or other members and sell electricity. The problem is modeled as a mixed-integer
linear programing (MILP) formulation and solved within a decentralized and iterative process. The
decentralized implementation provides acceptable solutions with a reasonable execution time,
while the centralized implementation usually gives an optimal solution at the expense of reduced
scalability. Preliminary results indicate that there are advantages for EVs as participants of the
LEM, and the proposed implementation ensures an optimal solution in an acceptable execution
time. Moreover, P2V transactions benefit the local distribution grid and the energy community.This work has received funding from FEDER Funds through COMPETE program and from National Funds through (FCT) under the projects CENERGETIC (PTDC/EEI-EEE/28983/2017), CEECIND/02814/2017 (JS grant), SFRH/BD/133086/2017 (RF PhD grant). We also acknowledge the work facilities and equipment provided by GECAD research center (UIDB/00760/2020) to the project team. Brazilian Federal Agency for Support and Evaluation of Graduate Education (CAPES), in the scope of the Program CAPES-PrInt, process number 88887.310463/2018-00, International Cooperation Project number 5-P2-1479.info:eu-repo/semantics/publishedVersio
Preoperative 99mTc-sestamibi scintigraphy in patients with primary hyperparathyroidism and concomitant nodular goiter: Comparison of SPECT-CT, SPECT, and planar imaging
Background: Investigations using a hybrid single photon emission computed tomography/computed tomography (SPECT-CT) scanning technique have been carried out in limited studies and have shown mixed results. However, the assessment of this technique for the detection of parathyroid adenoma in patients with a nodular goiter was performed in only one study with a small sample size. The aim of this prospective study was to assess the role of Tc-sestamibi parathyroid SPECT-CT scans for localization of parathyroid adenomas with a concomitant nodular goiter using Tc-methoxyisobutyl isonitrile (MIBI) scintigraphy and to compare it with SPECT and planar imaging. Methods: This study was conducted on 48 patients with primary hyperparathyroidism and nodular goiter, who were candidates for parathyroid surgery and had been referred for parathyroid scintigraphy. The patients underwent an early set of planar Tc-MIBI scanning procedures first, followed by SPECT and CT scannings, and finally a delayed set of planar Tc-MIBI scannings. Sensitivity, specificity, negative and positive predictive values, and accuracy were determined on a per-parathyroid-gland basis for each scanning method, as defined by histology and follow-up. Results: The surgery was successful in 48 out of 50 patients with primary hyperparathyroidism concomitant with thyroid nodularity, and data were completed for 80 sites in 48 patients. The accuracy of SPECT-CT in correctly identifying a parathyroid adenoma was 85.00, versus 75.00% for SPECT (P=0.01, significant). The sensitivity and specificity for SPECT-CT were 77.55 and 96.77%, respectively, versus 67.34 and 87.09%, respectively, for SPECT (P=0.12 and 0.12, not significant). There were nine sites that showed better localization on SPECT-CT scans relative to SPECT images, of which five sites were located in the ectopic regions. Conclusion: The results of our study indicate that SPECT-CT is more accurate than sestamibi planar imaging and SPECT for the preoperative identification of parathyroid lesions in patients with primary hyperparathyroidism concomitant with thyroid nodularity. Also, we would recommend the use of SPECT-CT for a workup of all patients with ectopic glands who are scheduled for minimally invasive parathyroid surgery. © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Interlaminar Fracture Toughness Evaluation in Glass/Epoxy Composites Using Acoustic Emission and Finite Element Methods
© 2014, ASM International. Delamination is one of the most common modes of failure in laminated composites and it leads to the loss of structural strength and stiffness. In this paper, mode I, mode II, and mixed of these pure modes were investigated using mechanical data, Finite Element Method (FEM) and Acoustic Emission (AE) signals. Experimental data were obtained from insitu monitoring of glass/epoxy laminated composites with different lay-ups when subjected to different modes of failure. The main objective was to investigate the behavior of delamination propagation and to evaluate the critical value of the strain energy which is required for onset of the delamination (GC). For the identification of interlaminar fracture toughness of the specimens, four methods were used: (a) ASTM standard methods, (b) FEM analysis, (c) AE method, and (d) sentry function method which is a function of mechanical and AE behaviors of the specimens. The results showed that the GC values obtained by the sentry function method and FEM analysis were in a close agreement with the results of nonlinearity methods which is recommended in the ASTM standards. It was also found that the specimens under different loading conditions and various lay-up have different GC values. These differences are related to different stress components distribution in the specimens which induce various damage mechanisms. Accordingly, stress components distribution obtained from FEM analyses were in agreement with SEM observations of the damaged surfaces of the specimens
Recommended from our members
A comprehensive review of nanocomposite PVDF as a piezoelectric material: evaluating manufacturing methods, energy efficiency and performance
Given the escalating concerns surrounding high energy consumption during manufacturing and the environmental impact of piezoelectric materials, the pursuit of sustainable alternatives has emerged as a critical challenge in shaping our technological future. In light of this imperative, this review paper investigates the domain of polymeric piezoelectric materials, with a specific focus on Polyvinylidene fluoride (PVDF) as a promising avenue for sustainable piezoelectric materials with a low-energy production process. The primary objective of this investigation is to conduct a comprehensive assessment of the existing research on the manufacturing processes of polymeric piezoelectric materials to enhance piezoelectric properties while minimizing energy-intensive production techniques. Through rigorous evaluation, the effectiveness of each manufacturing method is scrutinized, enabling the identification of the most energy-efficient approaches. This review paper paves the way for sustainable development and advancement of piezoelectric technologies
CASPER: A Hypermedia Departmental Information System
ABSTRACT: In this paper we discuss the design and development of CASPER (Computer Assisted Studies Planning and Educational Resources). CASPER is a hypermedia information system which allows students to find up to date information on courses, instructors, announcements, transfer credit, and frequently asked questions. One of the most important features of CASPER is its capability to assist students in planning their course selections for future terms. Because CASPER is an on-line system, additional human counselors are free to deal personally with students on less routine matters
- …