Effective HPLC method development

High Pressure Liquid Chromatography (HPLC) method development plays an important role in the discovery, development and manufacture of pharmaceutical products and day to day quality work in the laboratory. This article focuses on the effective method development of HPLC. It highlights pertinent conditions and other important perspectives during method development.  A sequence of events required for effective method development is described. The steps involved in developing a stability-indicating HPLC method influences the analysis of degradation products/impurities in stability study and its validation demonstrate the suitability for its intended purpose. Keywords: Method development, High Pressure Liquid Chromatography (HPLC), analytes

Forage Options for Tanzania Southern Highlands: Preliminary Assessment

In adequate quality and quantity, forages curtail animal production in sub-Saharan Africa. As such, the potential of livestock agriculture to contribute to household nutrition and incomes is usually compromised, against an increasing consumption of animal source foods. The growing consumption deserve forage interventions that can address the feeding gap, and contribute to improved livestock production, and subsequently livestock keepers’ prosperity. Using “Targeting Tools”, a web GIS system, we mapped the suitability of a wide array of grass and forage legumes for southern highlands. Using the maps, we selected context-specific varieties and procured available seeds/planting materials for pilot trials. Following farmers’ participatory approach, we established forage trials in three districts namely, Mufindi, Njombe and Rugwe of southern Tanzania highlands comprising of fourteen forage treatments. The test forages included; two Cenchrus purpureus (Syn. Pennisetum purpureum) cultivars, two Urochloa (Syn. Brachiaria) hybrids and Chloris gayana. Where applicable, we intercropped the grasses with three forage legumes- Lablab purpureus, Stylosanthes guianensis, and Desmodium intortum, while Tripsacum andersonii (Syn. Tripsacum laxum), a grass, was planted as a local check. We observed clear differences amongst the three districts and treatments. Dry matter accumulation (t ha−1) in the districts, and across the various forage treatments was in the order Rugwe>Mufindi>Njombe, even when accumulation kg DM day−1 was considered, in the early harvests. Most DM accumulation was by Napier grass intercropped with Lablab purpureus that was closely comparable to Chloris gayana-Desmodium intercrop. Further observations across more cuttings, farmer’ preference rankings and quality analysis are under way to inform reliable conclusions. The results would be applicable elsewhere with similar agricultural context and ecologies

Livestock Feeds Assessment in Southern Highlands in Tanzania

Importance of livestock in smallholder farms in Africa continue to be significant in households’ nutrition, incomes and for socio-cultural reasons. However, the sector faces various challenges including management, diseases and feeding among others. With the estimated doubling of demand for animal source foods especially in sub-Saharan Africa, due to rise in human population, efforts for improving livestock productivity are needed. Amongst the costs involved in cattle production, the feeding component takes 70% suggesting greater attention is required in feeding interventions for success to be realised. In an effort to contribute to improvement of livestock production in Southern Tanzania highlands, current feeding status was assessed in 3 districts (Mufindi, Njombe, Rugwe) following Feeds Assessment Tool protocol (FEAST https://www.ilri.org/feast). Information captured entailed; land size categories, livestock species reared, feed resources and seasonality, contribution of livestock to household incomes and most suited interventions were elucidated. In the three districts, dairy remains most prevalent amongst livestock species kept, and livestock in general is important for household incomes. Analysis suggest interventions on feeds and forages addressing protein and energy supply would be crucial, including forages suitable under cut and carry context, prevalent under smallholder farmers settings. Dry seasons are Characterized by inadequate feed resources. The information will guide selection of forage options to be tested through farmer participation, under Climate Smart Dairy Project (2019-2021) in the three districts. Identified farmer acceptable and productive forages will be recommended for the areas other similar ecologies, and by extension support forage development in Tanzania

Inelastic π--p Interactions in the Energy Region of 310 to 454 MeV

Differential cross sections for positive pions, protons, and neutrons resulting from inelastic π--p collisions have been measured from 310- to 454-MeV incident-pion kinetic energy. The data were obtained with electronic counter systems, which measured the energy distribution of the final-state particle of interest at a series of fixed angles. The results have been interpreted in terms of the final states π+π-n, π0π0n, and π-π0p. The total cross sections for these three modes as a function of incident pion energy are in qualitative agreement with the predictions by Schnitzer. A preference is shown for his set of π-π scattering lengths; a0=0.65, a1=0.07, and a2=-0.14μ-1. The observed neutron distributions correspond to a strong preference for low c.m.-system neutron energies in both the π+π-n and π0π0n final states. The effect is not present in the observed proton distributions from the π-π0p reaction, which suggests that it is due to a I=0, π-π interaction. The π+ data show the formation of the (3,3) isobar combination of the π--n system in the π+π-n final state. Analysis in terms of an isobar model indicates the predominance of I=1/2 incident state

Facial Emotion Recognition with Sparse Coding Descriptor

With the Corona Virus Disease 2019 (COVID-19) global pandemic ravaging the world, all sectors of life were affected including education. This led to many schools taking distance learning through the use of computer as a safer option. Facial emotion means a lot to teacher’s assessment of his performance and relation to his students. Researchers has been working on improving the face monitoring and human machine interface. In this paper we presented different types of face recognition methods which include: Principal component analysis (PCA); Speeded Up Robust Features (SURF); Local binary pattern (LBP); Gray-Level Co-occurrence Matrix (GLCM) and also the group sparse coding (GSC) and come up with the fusion of LBP, PCA, SURF GLCM with GSC. Linear Kernel Support Vector Machine (LSVM) Classifier out-performed Polynomial, RBF and Sigmoid kernels SVM in the emotion classification. Results obtained from experiments indicated that, the new fusion method is capable of differentiating different types of face emotions with higher accuracy compare with the state-of-the-art methods currently available

Lack of Macrolide Resistance in Chlamydia trachomatis after Mass Azithromycin Distributions for Trachoma

We investigated antimicrobial drug resistance in ocular Chlamydia trachomatis 18 months after 4 biannual communitywide distributions of antimicrobial drugs in a region of Ethiopia where ocular strains of C. trachomatis are highly endemic. We found no significant differences in susceptibilities to azithromycin and doxycycline in 6 posttreatment and 4 pretreatment samples

Pion production by negative pions

The reaction π- + p → π- + π+ + n, for T π incident = 365 Mev and 432 Mev, was studied. In a previous experiment Perkins et al. investigated this reaction.(1

Pi±-p total cross sections in the range 450 Mev to 1650 Mev

A series of counter experiments is being carried out at the Berkeley Bevatron and 184-inch cyclotron to measure total and differential scattering cross sections for pions at energies above the first resonance. (1-3) In this Letter we report the results of measurements of the total cross section for positive and negative pions on protons in the energy range from 450-Mev to 1650-Mev pion kinetic energy (lab)

Positive-pion production in inelastic π-p interactions between 500 and 1300 MeV

The momentum distributions of the π+ in the reaction π-p→π+π-n were measured at several π+ angles for incident π- beam energies of 516, 550, 599, 667, and 715 MeV; π-n mass spectra were calculated from the π+ momentum distributions. Partial data were also obtained at higher energies. The π- beam was obtained from the Berkeley Bevatron. The momenta of the π+ were measured with a magnetic spectrometer consisting of a C magnet and thin-walled aluminum spark chambers to display the trajectory of the particle entering and leaving the magnet. An array of scintillation counters was used to detect the occurrence of an event. An electronic time-of-flight system was used to distinguish positive pions from protons that passed through the spectrometer. The measured spectra can not be adequately explained by any of the several models with which we tried to fit our spectra, including an isobar model, although production of the (3,3) isobar is prominent