Bifurcation and Chaos in Coupled Ratchets exhibiting Synchronized Dynamics

The bifurcation and chaotic behaviour of unidirectionally coupled deterministic ratchets is studied as a function of the driving force amplitude ($a$) and frequency ($\omega$). A classification of the various types of bifurcations likely to be encountered in this system was done by examining the stability of the steady state in linear response as well as constructing a two-parameter phase diagram in the ($a -\omega$) plane. Numerical explorations revealed varieties of bifurcation sequences including quasiperiodic route to chaos. Besides, the familiar period-doubling and crises route to chaos exhibited by the one-dimensional ratchet were also found. In addition, the coupled ratchets display symmetry-breaking, saddle-nodes and bubbles of bifurcations. Chaotic behaviour is characterized by using the sensitivity to initial condition as well as the Lyapunov exponent spectrum; while a perusal of the phase space projected in the Poincar$\acute{e}$ cross-section confirms some of the striking features.Comment: 7 pages; 8 figure

Effect of Two Cowpea (Vigna unguiculata) Fodder Cultivars as Supplements on Voluntary Intake; Milk Yield and Manure Production of Bunaji Cows

The feeding value of fodder from two cowpea cultivars to a basal maize stover diet was investigated using fifteen lactating White Fulani (Zebu) cows. The two cultivars were IT-716 and 994-DP. Diet was constituted as 50g DM/kg live weight and each of the cultivars was supplemented at 50% of the daily dry matter requirement of individual animals. The experimental design was a complete randomize. The parameters measured included feed intake, milk yield and composition and manure production. In a separate trial, dry matter degradation of the fodder was assessed. There were no significant differences in dry matter intake of the supplements. However, the dry matter intake of stover in the control diet was higher than those on the supplemented groups. The milk yields ranged from 887 to 1378 ml/day. Milk yield differed among treatments. Supplementation did not affect (P 0.05) fat, protein, total solids and ash contents of the milk across the treatments. Manure productions were not significantly different among the treatments. Similarly, content of N, P and K in manure were comparable among the treatments except for N that was lower (P 0.05) in the control group. The dry matter degradation was influenced by the fodder cultivars. The feeding of dual-purpose forage legumes residues could enhance milk production in lactating Zebu cows. This may be further increased by exploring other ways of improving feed residue utilization in the dry season

Effect of Manure Application on Herbage Yield, Nutritive Value and Performance of Wad Sheep Fed Panicum maximum

Effect of types of manure on herbage yield, nutritive value and performance of WAD Sheep fed native Panicum maximum was investigated. The experiment was laid out in a randomized complete block design with each plot replicated thrice. Poultry manure and sheep - goat manure were applied through broadcasting to an established Panicum maximum stand to supply 200kgN/ha and 0kgN/ha (control). Grass herbage harvested from experiment plot were fed as sole diets to West African dwarf sheep to determine feed intake (g/h/d), nutrient digestibility (%) and weight gain (g/h/d). Results showed that Panicum maximum fertilized with poultry manure produced (P<0.05) higher values for biomass yield, number of tillers, tiller height, leaf length and leaf width. The chemical composition of Panicum maximum fertilized with poultry manure produced (P<0.05) higher CP and GE compared to sheep-goat manure. Similar trend of result was observed on mineral composition of Panicum maximum fertilized with poultry manure produced (P<0.05) higher values for P, K, Ca, Mg, Fe, Zn and Cu compared to sheep-goat manure. The feed intake (g/h/d), nutrient digestibility (%) and weight gain of the animals fed Panicum maximum fertilized with poultry manure produced higher values compared to its counterpart. It was concluded based on data obtained from this study that poultry manure application will promote higher yield and nutritive value for the Panicum maximum. Animals fed with this as sole diet and as short feeding regime experienced high weight gain. Keywords: Poultry manure, sheep - goat manure, herbage yield, Panicum maximum, WAD Shee

Effect of Manure Application on Herbage Yield, Nutritive Value and Performance of Wad Sheep Fed Panicum maximum

Effect of types of manure on herbage yield, nutritive value and performance of WAD Sheep fed native Panicum maximum was investigated. The experiment was laid out in a randomized complete block design with each plot replicated thrice. Poultry manure and sheep - goat manure were applied through broadcasting to an established Panicum maximum stand to supply 200kgN/ha and 0kgN/ha (control). Grass herbage harvested from experiment plot were fed as sole diets to West African dwarf sheep to determine feed intake (g/h/d), nutrient digestibility (%) and weight gain (g/h/d). Results showed that Panicum maximum fertilized with poultry manure produced (P<0.05) higher values for biomass yield, number of tillers, tiller height, leaf length and leaf width. The chemical composition of Panicum maximum fertilized with poultry manure produced (P<0.05) higher CP and GE compared to sheep-goat manure. Similar trend of result was observed on mineral composition of Panicum maximum fertilized with poultry manure produced (P<0.05) higher values for P, K, Ca, Mg, Fe, Zn and Cu compared to sheep-goat manure. The feed intake (g/h/d), nutrient digestibility (%) and weight gain of the animals fed Panicum maximum fertilized with poultry manure produced higher values compared to its counterpart. It was concluded based on data obtained from this study that poultry manure application will promote higher yield and nutritive value for the Panicum maximum. Animals fed with this as sole diet and as short feeding regime experienced high weight gain

Conjunctivitis in dupilumab clinical trials

Background Dupilumab blocks the shared receptor component for interleukin (IL)-4 and IL-13. It is approved in the U.S.A. for patients aged ≥ 12 years with moderate-tosevere atopic dermatitis (AD) uncontrolled by topical prescription medicines or who cannot use topical medicines, for patients in Japan whose AD is uncontrolled with existing therapies, for patients with moderate-to-severe AD in Europe who are candidates for systemic therapy and for patients aged ≥ 12 years for maintenance treatment of moderate-to-severe asthma uncontrolled with their current medicines. AD trials have reported increased incidence of conjunctivitis for dupilumab vs. placebo. Objectives To characterize further the occurrence and risk factors of conjunctivitis in dupilumab clinical trials. Methods We evaluated randomized placebo-controlled trials of dupilumab in AD (n = 2629), asthma (n = 2876), chronic rhinosinusitis with nasal polyps (CRSwNP) (n = 60) and eosinophilic oesophagitis (EoE) (n = 47). Results In most AD trials, dupilumab-treated patients had higher conjunctivitis incidence than placebo controls. Higher baseline AD severity and previous history of conjunctivitis were associated with increased conjunctivitis incidence. Conjunctivitis was mostly mild to moderate. Most cases recovered or resolved during the treatment period; two patients permanently discontinued dupilumab due to conjunctivitis or keratitis. Common treatments included ophthalmic corticosteroids, antibiotics, and antihistamines or mast cell stabilizers. Most cases were diagnosed by the investigators. In asthma and CRSwNP trials, the incidence of conjunctivitis was lower for both dupilumab and placebo than in AD trials; dupilumab did not increase the incidence compared with placebo. In the EoE trial, no patients had conjunctivitis. Conclusions Conjunctivitis was more frequent with dupilumab treatment in most AD trials. In dupilumab trials in other type 2 diseases, incidence of conjunctivitis was overall very low, and was similar for dupilumab and placebo. In AD, the incidence of conjunctivitis was associated with AD severity and prior history of conjunctivitis. The aetiology and treatment of conjunctivitis in dupilumab-treated patients require further study

Effects of cotton seed cake supplementation on the dry season performance of white Borno goats

No Abstract

Effect of Three Species of Stylosanthes on The Performance of West African Dwarf Sheep

An experiment was conducted to determine the effect of feeding three species of Stylosanthes as supplements to a basal diet consisting of Cyonodon dactylon on the performance of West African dwarf sheep. The three treatments imposed were: Treatment 1, a basal diet consisting of poor quality grass (Cyondon dactylon) and Stylosanthes scabra in the ratio of 70:30. Treatment 2, the basal diet added with Stylosanthes guianensis (70:30); and Treatment 3,the basal diet with Stylosanthes hamata (70:30). The study lasted for 24 days, a 10 day adjustment period and a 14- day data collection, using 3 rams of comparable age and weight. Data were analyzed as a 3 x 3 Latin square. Animals supplemented with S. guianensis had the highest DM intake while S. scabra was least consumed by sheep (p<0.05). Digestibility of crude protein and DM however showed that animals on S. guianensis performed better. It could be concluded that sheep can be supplemented with Stylosanthes guianensis in the savannah zone of Nigeria. Keywords: Stylosanthes guianensis; Stylosanthes scabra; Stylosanthes hamate; West African Dwarf sheep; crude protein digestibilit

CAUSAL EFFECT OF CREDIT AND TECHNOLOGY ADOPTION ON FARM OUTPUT AND INCOME: THE CASE OF CASSAVA FARMERS IN SOUTHWEST NIGERIA

This study examined credit accessibility, technology adoption and the impact on output and income of cassava farming households in Southwest Nigeria. Data were collected using structured questionnaire through a multi-stage sampling procedure. Ondo and Ogun states were randomly selected from the six States in Southwest, Nigeria. The next stage involved the random selection of four Local Government Areas from each State. Finally, a total of five hundred and forty cassava farmers were randomly selected from both States. Propensity Score Matching, descriptive statistics and Tobit regression model were employed in the analysis. There were 387 respondents with similar characteristics. Majority of the farmers were males with mean household size of six members. Average area of land cultivated was about 1 hectare. Credit accessibility was higher among the adopters. Credit access had a positive and significant (p<0.01) influence on level of adoption. Cassava yield and income (14.92 tonnes/ha and ₦321,758.00 respectively) of adopters with credit was higher than their counterparts (13.06 tonnes/ha and ₦287,110.90) without credit access. The impact of technology adoption was higher among adopters with credit access. Technology adoption increased cassava yield and income of adopters with credit access by 4.68tonnes/ha and ₦64,945.19 respectively compared with 2.57 tonnes/ha and ₦33,964.79 for those without access. This suggests that access to credit and technology adoption have the potential to transform smallholder agriculture in Nigeria. The study recommends that government should invest more on technology advancement and dissemination among smallholder farmers. Policy measures should also be oriented towards the improvement of rural credit

Commercialization of Urban Farming: The Case of Vegetable Farmers in Southwest Nigeria

Markets and improved market access are critical for improving urban incomes, particularly in Africa. Despite this, participation of farmers in domestic and regional markets in southwest Nigeria remains low due to a range of constraints. One of the limiting constraints faced by farmers is linked to poor market access. This paper analyses the determinants of commercialization of urban vegetable farming in southwest Nigeria. Primary data were collected for the purpose of this study using structured questionnaire. A multi-stage sampling technique was employed for the study. Oyo and Lagos states were randomly selected from the six states in the southwest Nigeria. The next stage was random selection of two urban Local Government Areas from the selected states. Two hundred and thirty (230) vegetable farmers were randomly selected from both states. The data were analysed using descriptive statistics and Tobit model. Mean age and household size of farmers in the area was 41.9 years and six members respectively. Vegetable farmers are smallholders with average farm size of 0.05ha. Average market participation index of urban vegetable farmers was 0.73. Result of Tobit regression showed that age, age squared, farm size, membership of association, years of education, distance to market, heterogeneity index, cost of fertilizer, cost of chemicals and decision making index influenced extent of commercialization. Social capital significantly affects market participation. The study recommends that governments, non-governmental organizations and other development partners should take a pro-active role in facilitating the formation of smallholder vegetable farmer’s organizations and linking then to markets

Alpha amylase inhibition and antioxidant activities of bicyclic diterpenoid lactones from Andrographis paniculata

Andrographis paniculata is an important medicinal plant reported for its efficacy in the treatment and management of various medical conditions in different parts of the world. This study evaluates the α-amylase inhibitory and antioxidant activities of the crude extracts, solvent fractions and isolated compounds from aerial parts of A. paniculata. Chromatographic fractionation of the aqueous methanol fraction led to isolation of 14-deoxyandrographolide (1) and andrographolide (2). The isolated compounds were characterized by set of spectroscopic techniques such as nuclear magnetic resonance (NMR), infrared (IR) spectroscopy, mass spectrometry (MS) and their structures were confirmed by x-ray crystallography and by comparison of data with literature. The extract, fractions and isolated compounds were evaluated for anti-diabetic and antioxidant activities. Aqueous methanol fraction displayed the highest amount of total phenolic (TPC) and flavonoid content (TFC) of 9.42 ± 0.95 mg gallic acid equivalent/g (mg GAE/g) and 40.08 ± 17.93 mg quercetin equivalent/g (mg QUE/g) respectively amongst the extract and fractions. The aqueous methanol fraction, crude methanol extract and nhexane fraction exhibited better α-amylase inhibitory activity with an inhibitory concentration (IC50) of 0.057 ± 0.012, 0.0610 ± 0.035 and 0.080 ± 0.021 mg/mL respectively than acarbose, a standard reference drug with an IC50 value of 0.127 ± 0.013 mg/mL. Compound 1 and 2 exhibited a lower inhibitory activity with an (IC50) values of 0.637 ± 0.003 and 0.761 ± 0.013 mg/mL respectively. The results of these study on A. paniculata may justify its traditional use in the management of diabetes mellitus.http://link.springer.com/journal/11250pm2022Chemistr