99 research outputs found

    Analysis of Cowpea (Vigna unguiculata) Marketing and Price Trends in Selected Markets of Argungu Local Government Area, Kebbi State, Nigeria

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    The study analyzed cowpea marketing and price trends in selected rural and urban markets of Argungu Local Government Area, Kebbi State, Nigeria. A single-stage sampling technique was used for sample selection. The samples were collected from purposively selected Kara markets in Argungu (reference market), Felande, Gulma, Lailaba and Sauwa (supplying markets) from the selected Districts. Primary data were obtained from a sample of 100 marketers with the aid of the structured questionnaire. Descriptive statistics and spatial price model were employed in analyzing the data. Results of the analysis shows an average age of marketers to be 34 years, 69% were married and 62% have formal education with an average household size of 8 persons. However, 73% were discovered not join any cooperative association while 79% of them do not have access to credit to finance their business. Analysis of spatial aspects of pricing efficiency showed that the positive price spread is slightly high, even after considering plausible levels of unmeasured transaction costs. The trend in price revealed higher price per bag during the off-season (N27, 000/bag) in July and August and low (N15, 000) during harvest (October,November, December and January). Temporal aspects showed considerable risk was involved in storage operations to achieve high profits. The marketing channels identified in the study area were; Farmers, Village merchants, Wholesalers, Retailers, Processors and finally the Consumers. The constraints identified in the study area were lack of access to credit (25.69%), inadequate market information (24.59%), inadequate market infrastructure (22.65%), provision of quality product (16.02%) and poor storage facilities (11.05%). It is recommended that sellers should form cooperatives that can support them in provision of physical facilities and better dissemination of market intelligence and facts. Accordingly, to alleviate the problem of access to credit in the study area, awareness campaign and provision of such credit facilities at affordable level by the relevant stakeholders (State and Local Government authorities) could be an excellent  performance in enhancing the marketing activities in the study area

    Synthesis of New Series of Pyrazoline, and Study their Kinetics and Reaction Mechanism

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    A new series of novel pyrazoline compounds were synthesized by addition of thiosemicarbazide to the 2,6-dibenzylidenecyclohexanone (Chalcone) and its para substituted derivatives. This study was conducted for four purposes. Firstly, a series of five membered ring pyrazoline compounds were synthesized and the structure of all new products obtained are supported by spectral data (1H-NMR, 13CNMR, IR and UV-Vis.), and the effect of substituents were studied. Secondly, the reaction kinetics of the new synthesized compounds were studied to investigate the reaction mechanism pathway and order of the reaction; it was found that, the reaction undergoes via Claisen route of mechanism with first-order reaction. Thirdly, the thermodynamics of the reaction were studied, the rate of the reaction, Arrhenius parameters (A), and thermodynamic parameters for activation includes (free energies (Ea), entropies (ΔS#), and Gibbs free energy (ΔG#) were estimated. Finally, the compensation effect was also studied, and found the same pathway for all of the synthesized pyrazoline compounds

    Large microwave generation from d.c. driven magnetic vortex oscillators in magnetic tunnel junctions

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    Spin polarized current can excite the magnetization of a ferromagnet through the transfer of spin angular momentum to the local spin system. This pure spin-related transport phenomena leads to alluring possibilities for the achievement of a nanometer scale, CMOS compatible and tunable microwave generator operating at low bias for future wireless communications. Microwave emission generated by the persitent motion of magnetic vortices induced by spin transfer effect seems to be a unique manner to reach appropriate spectral linewidth. However, in metallic systems, where such vortex oscillations have been observed, the resulting microwave power is much too small. Here we present experimental evidences of spin-transfer induced core vortex precessions in MgO-based magnetic tunnel junctions with similar good spectral quality but an emitted power at least one order of magnitude stronger. More importantly, unlike to others spin transfer excitations, the thorough comparison between experimental results and models provide a clear textbook illustration of the mechanisms of vortex precessions induced by spin transfer

    Current-induced microwave excitation of a domain wall confined in a magnetic wire with bi-axial anisotropy

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    We studied the current-induced magnetization dynamics of a domain wall confined in a magnetic wire with bi-axial anisotropy. We showed that above the threshold current density, breathing-mode excitation, where the thickness of the domain wall oscillates, is induced by spin-transfer torque. We found that the breathing-mode can be applied as a source of microwave oscillation because the resistance of the domain wall is a function of the domain wall thickness. In a current sweep simulation, the frequency of the breathing-mode exhibits hysteresis because of the confinement.Comment: 5 pages 4 figure

    Adoptive T-cell therapy improves treatment of canine non–Hodgkin lymphoma post chemotherapy

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    Clinical observations reveal that an augmented pace of T-cell recovery after chemotherapy correlates with improved tumor-free survival, suggesting the add-back of T cells after chemotherapy may improve outcomes. To evaluate adoptive immunotherapy treatment for B-lineage non-Hodgkin lymphoma (NHL), we expanded T cells from client-owned canines diagnosed with NHL on artificial antigen presenting cells (aAPC) in the presence of human interleukin (IL)-2 and IL-21. Graded doses of autologous T cells were infused after CHOP chemotherapy and persisted for 49 days, homed to tumor, and significantly improved survival. Serum thymidine kinase changes predicted T-cell engraftment, while anti-tumor effects correlated with neutrophil-to-lymphocyte ratios and granzyme B expression in manufactured T cells. Therefore, chemotherapy can be used to modulate infused T-cell responses to enhance anti-tumor effects. The companion canine model has translational implications for human immunotherapy which can be readily exploited since clinical-grade canine and human T cells are propagated using identical approaches

    Intraperitoneal drain placement and outcomes after elective colorectal surgery: international matched, prospective, cohort study

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    Despite current guidelines, intraperitoneal drain placement after elective colorectal surgery remains widespread. Drains were not associated with earlier detection of intraperitoneal collections, but were associated with prolonged hospital stay and increased risk of surgical-site infections.Background Many surgeons routinely place intraperitoneal drains after elective colorectal surgery. However, enhanced recovery after surgery guidelines recommend against their routine use owing to a lack of clear clinical benefit. This study aimed to describe international variation in intraperitoneal drain placement and the safety of this practice. Methods COMPASS (COMPlicAted intra-abdominal collectionS after colorectal Surgery) was a prospective, international, cohort study which enrolled consecutive adults undergoing elective colorectal surgery (February to March 2020). The primary outcome was the rate of intraperitoneal drain placement. Secondary outcomes included: rate and time to diagnosis of postoperative intraperitoneal collections; rate of surgical site infections (SSIs); time to discharge; and 30-day major postoperative complications (Clavien-Dindo grade at least III). After propensity score matching, multivariable logistic regression and Cox proportional hazards regression were used to estimate the independent association of the secondary outcomes with drain placement. Results Overall, 1805 patients from 22 countries were included (798 women, 44.2 per cent; median age 67.0 years). The drain insertion rate was 51.9 per cent (937 patients). After matching, drains were not associated with reduced rates (odds ratio (OR) 1.33, 95 per cent c.i. 0.79 to 2.23; P = 0.287) or earlier detection (hazard ratio (HR) 0.87, 0.33 to 2.31; P = 0.780) of collections. Although not associated with worse major postoperative complications (OR 1.09, 0.68 to 1.75; P = 0.709), drains were associated with delayed hospital discharge (HR 0.58, 0.52 to 0.66; P < 0.001) and an increased risk of SSIs (OR 2.47, 1.50 to 4.05; P < 0.001). Conclusion Intraperitoneal drain placement after elective colorectal surgery is not associated with earlier detection of postoperative collections, but prolongs hospital stay and increases SSI risk

    Biology and Impacts of Pacific Island Invasive Species. 6. Prosopis pallida

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