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In this study, the effects were investigated of salinity, foliar and soil applications of humic substances on the growth and mineral nutrients uptake of Corn (Hagein, Fardy10), and the comparison was carried out of the soil and foliar applications of humic acid treatments at different NaCl levels. Soil organic contents are one of the most important parts that they directly affect the soil fertility and textures with their complex and heterogenous structures although they occupy a minor percentage of the soil weight. Humic acids are an important soil component that can improve nutrient availability and impact on other important chemical, biological, and physical properties of soils. The effects of foliar and soil applications of humic substances on the plant growth and some nutrient elements uptake of Corn (Hagein, Fardy10) grown at various salt concentrations were examined. Sodium chloride was added to the soil to obtain 20 and 60mM saline conditions. Solid humus was applied to the soil one month before planting and liquid humic acids were sprayed on the leaves twice on 20th and 40th day after seedling emergence. The application doses of solid humus were 0, 2 and 4 g/kg and those of liquid humic acids were 0, 0.1 and 0.2%. Salinity negatively affected the growth of corn; it also decreased the dry weight and the uptake of nutrient elements except for Na and Mn. Soil application of humus increased the N uptake of corn while foliar application of humic acids increased the uptake of P, K, Mg,Na,Cu and Zn. Although the effect of interaction between salt and soil humus application was found statistically significant, the interaction effect between salt and foliar humic acids treatment was not found significant. Under salt stress, the first doses of both soil and foliar application of humic substances increased the uptake of nutrients.

Current concern for soil quality has stimulated research on soil organic matter (OM). Humic substances (HS) of different origin were compared applying ultraviolet-visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), “steady-state” fluorescence spectroscopy, and 13C nuclear magnetic resonance (13C NMR). Sodium humates samples were isolated from soil (Gleyic Luvisol), compost, and South-Moravian lignite from the mine Mír in Mikulčice. Sodium humates (SH) were extracted by a conventional procedure recommended by the International Humic Substances Society (IHSS). Results showed that the presence of O-containing functional groups (carbonyl in aldehydes and ketones, carboxyl in carboxylic acids, ester and ether groups) are in the order of compost > soil > lignohumate > lignite. Further, results of FTIR, fluorescence spectroscopy, and 13C NMR suggested that samples of sodium humates isolated from soil, compost, and lignite were a more polycondensed, oxidized, unsaturated, humified, and aromatic structure. On the other hand, commercial lignohumate (LH) had very simple structural components and wide molecular heterogeneity. Furthermore, a small molecular size and weight, low degree of aromatic polycondensation, low level of conjugated chromophores and fluorophores, and low humification degree were characteristic for commercial LH. It should be noted that the sample of commercial LH was characterized by 13C NMR analysis with a slightly higher value of aromaticity α in comparison with the sample of compost. The application of non-destructive analytical methods such as UV-VIS, FTIR, 13C NMR, and fluorescence spectroscopy help us to provide main characteristics of selected humic substances.

In North Africa, the parasite Echinococcus granulosus is transmitted in a synanthropic cycle evolving mainly between dogs (DH) and sheep (IH), but other animals like cattle are most often found to be more infested with hydatid cysts but their potential role in human contamination via dogs is unknown. The purpose of this study is to assess the prevalence and fertility rates of hydatid cysts in ruminants (cattle and sheep) in two slaughterhouses in central and eastern Algeria. Determining the frequency and fertility of cysts in cattle will assess the degree of involvement of this species, alongside sheep, in the epidemiological cycle of E. granulosus in Algeria. In the present study, prevalence rates were estimated at 4.9% and 10% in slaughtered ruminants, all species combined at the slaughterhouses of El Harrach and Souk Ahras, respectively. The distribution of the prevalence by species indicates higher infestation rates in cattle compared to sheep: 6% vs 3.9% and 37% vs 4.7% in the slaughterhouses of El Harrach and Souk Ahras, respectively. The survey results showed relatively low cyst fertility rates in cattle compared to sheep: 13.8% vs 43.7% and 33.3% vs 71.4% in the two slaughterhouses, El Harrach and Souk Ahras, respectively. The low fertility rate of cysts in cattle can be explained by a poor adaptation of the species, E. granulosus sensu stricto, previously identified by molecular analysis in all samples of hydatid cysts collected from cattle in Algeria. In conclusion, cattle infested with E. granulosus sensu stricto, with low fertility rates, play a minor role in the epidemiology of cystic echinococcosis in Algeria. It is rather an indicator of the persistence of cystic echinococcosis infection in endemic regions.

Despite increased emphasis on antiretroviral therapy for HIV infected individuals, issues of fertility and childbearing have received relatively little attention in Ethiopia. This study was conducted to assess socio-demographic, reproductive and HIV related characteristics of fertility intention among women living with HIV in Western Ethiopia. Cross sectional study was conducted from May 1 to May 26, 2012 using structured questionnaire on a sample of 456 women living with HIV who are on follow up care in anti-retroviral therapy clinics. Bivariate and multivariable logistic regression models were fitted to identify significant predictors of fertility desire at 95 CL. Out of 456 respondents 42.1% expressed intention to have children in the future. Educational attainment [AOR (95% CI) = 0.041(0.008 -0.220)], partner fertility desire [AOR (95% CI) = 0.012(0.004-0.034)], number of live children [AOR (95% CI) = 0.344(0.125-0.950)] and partner sero-status [AOR (95% CI) = 6.578 (4.072-10.881)] were significantly associated with fertility intention. A large proportion of HIV-positive women in the study desired more children in future. Interventions to address this problem include integrated access to contraception methods, and counselling on reproductive health decision-making. Malgré l'accent augmenté mis sur la thérapie antirétrovirale pour les personnes infectées par le VIH, les questions de la fertilité et la procréation ont reçu relativement peu d'attention en Ethiopie. Cette étude a été menée pour évaluer les caractéristiques sociodémographiques, la reproduction et la fécondité liées au VIH de l'intention chez les femmes vivant avec le VIH en Ethiopie occidentale. Une étude transversale a été menée du 1 mai au 26 mai 2012 en utilisant ? l'aide d'un questionnaire structuré sur un échantillon de 456 femmes vivant avec le VIH qui sont sur le suivi des soins dans les cliniques de thérapie antirétroviraux. Les modèles de la régression Bi -variées et multi-variées ont été ajustés pour identifier les indices significatifs du désir de fécondité ? 95 CL. Parmi les 456 interrogées 42,1% ont exprimé l'intention d'avoir des enfants ? l'avenir. Le niveau de scolarité [AOR (IC 95%) = 0,041 (0,008 -0,220)], le désir de fertilité chez le partenaire [AOR (IC 95%) = 0,012 (de 0,004 ? 0,034)], nombre d'enfants vivants [AOR (IC ? 95% = 0,344) (0,125 ? 0,950)] et le statut sérologique du partenaire [AOR (IC 95%) = 6,578 (4,072 ? 10,881)] ont été statistiquement associé ? la l'intention de fertilité. Une grande proportion des femmes séropositives dans l'étude ont le désir d'avoir des enfants dans l'avenir. Les programmes ? élaborer devraient aborder un accès intégré aux méthodes de contraception, aux conseils sur la décision liée ? la reproduction ? la grossesse et ? l'accouchement sans risque.

Our aim in this study was to determine how well phenotypic variation in foliar concentrations of carbon-based secondary compounds (CBSCs) in woody plants can be predicted on the basis of two resource-based hypotheses i.e. the carbon-nutrient balance (CNB) and growth-differentiation balance (GDB) hypotheses. We conducted a meta-analysis of literature data with respect to responses of CBSCs, carbohydrates and nitrogen to six types of environmental manipulations (fertilization with nitrogen or phosphorus, shading, CO2 enrichment, drought stress, ozone exposure). Plant responses to nitrogen fertilization, shading and CO2 enrichment in terms of pooled CBSCs and carbohydrates were consistent with predictions made with the two hypotheses. However, among biosynthetically distinct groups of CBSCs only concentrations of phenylpropanoid-derived compounds changed as predicted; hydrolyzable tannins and terpenoids, in particular, were less responsive. Phosphorus fertilization did not affect concentrations of CBSC or primary metabolites. Plant responses to drought and ozone exposure presumably were driven by plant demands for particular types of compounds (osmolites in the case of drought and antioxidants in the case of ozone exposure) rather than by changes in resource availability. Based on the relative importance of the treatment effects, we propose a hierarchical model of carbon allocation to CBSCs. The model implies that CBSC production is determined by both resource availability and specific demand-side responses. However, these two mechanisms work at different hierarchical levels. The domain of the CNB and GDB hypotheses is at the high hierarchical levels, predicting the total amount of carbon that can be allocated to CBSCs. Predicting altered concentrations of individual CBSCs, i.e. low hierarchy levels, probably demands biosynthetically detailed models which also take into account the history of plant interactions with biotic and abiotic factors.

Recent experiments have provided some evidence that loss of biodiversity may impair the functioning and sustainability of ecosystems. However, we still lack adequate theories and models to provide robust generalizations, predictions, and interpretations for such results. Here I present a mechanistic model of a spatially structured ecosystem in which plants compete for a limiting soil nutrient. This model shows that plant species richness does not necessarily enhance ecosystem processes, but it identifies two types of factors that could generate such an effect: (i) complementarity among species in the space they occupy below ground and (ii) positive correlation between mean resource-use intensity and diversity. In both cases, the model predicts that plant biomass, primary productivity, and nutrient retention all increase with diversity, similar to results reported in recent field experiments. These two factors, however, have different implications for the understanding of the relationship between biodiversity and ecosystem functioning. The model also shows that the effect of species richness on productivity or other ecosystem processes is masked by the effects of physical environmental parameters on these processes. Therefore, comparisons among sites cannot reveal it, unless abiotic conditions are very tightly controlled. Identifying and separating out the mechanisms behind ecosystem responses to biodiversity should become the focus of future experiments

Variability in population growth rate is thought to have negative consequences for organism fitness. Theory for matrix population models predicts that variance in population growth rate should be the sum of the variance in each matrix entry times the squared sensitivity term for that matrix entry. I analyzed the stage-specific demography of 30 field populations from 17 published studies for pattern between the variance of a demographic term and its contribution to population growth. There were no instances in which a matrix entry both was highly variable and had a large effect on population growth rate; instead, correlations between estimates of temporal variance in a term and contribution to population growth (sensitivity or elasticity) were overwhelmingly negative. In addition, survivorship or growth sensitivities or elasticities always exceeded those of fecundity, implying that the former two terms always contributed more to population growth rate. These results suggest that variable life history stages tend to contribute relatively little to population growth rates because natural selection may alter life histories to minimize stages with both high sensitivity and high variation.

Studies of tree recruitment are many, but they provide few general insights into the role of recruitment limitation for population dynamics. That role depends on the vital rates (transitions) from seed production to sapling stages and on overall population growth. To determine the state of our understanding of recruitment limitation we examined how well we can estimate parameters corresponding to these vital rates. Our two-part analysis consists of (1) a survey of published literature to determine the spatial and temporal scale of sampling that is basis for parameter estimates, and (2) an analysis of extensive data sets to evaluate sampling intensity found in the literature. We find that published studies focus on fine spatial scales, emphasizing large numbers of small samples within a single stand, and tend not to sample multiple stands or variability across landscapes. Where multiple stands are sampled, sampling is often inconsistent. Sampling of seed rain, seed banks, and seedlings typically span <1 yr and rarely last 5 yr. Most studies of seeding establishment and growth consider effects of a single variable and a single life history stage. By examining how parameter estimates are affected by the spatial and temporal extent of sampling we find that few published studies are sufficiently extensive to capture the variability in recruitment stages. Early recruitment stages are especially variable and require samples across multiple years and multiple stands. Ironically, the longest duration data sets are used to estimate mortality rates, which are less variable (in time) than are early life history stages. Because variables that affect recruitment rates interact, studies of these interactions are needed to assess their full impacts. We conclude that greater attention to spatially extensive and longer duration sampling for early life history stages is needed to assess the role of recruitment limitation in forests.

In order to enhance the mass production of Musca domestica five aspects of its oviposition biology were analyzed. Oviposition substrate and the manner of its presentation, the composition of the diet of the adults, size of the pupae and numbers of flies in a cage were identified as critical. Females preferred to lay eggs on a substrate which was presented within a shelter and with increased linear edges against which the flies could oviposit. Different types of oviposition substrate resulted in comparable yields of eggs. The presence of an oviposition attractant (ammonia) in the manure was found to have a potentially positive effect on female fecundity. Egg yield increased when two protein sources (yeast and milk) were included in the adult diet. However, flies fed a mixture of sugar and yeast laid over 50% fewer eggs than those fed the same proportion of sugar and milk. The fecundity of flies decreased with the increase in the number of flies per cage, but the highest total number of eggs per cage was obtained with the highest density of flies (14.2 cubic cm per fly). The size of the pupae did not significantly affect egg production.