The advent of civilization has made humans dependent on plants for food and medicine, leading to the intensification of agricultural production. The intense cultivation of crops has resulted in the ...depletion of available nutrients from soil, thereby demanding the application of excess nutrients to soil to improve yield. Thus, mineral fertilizer discovery and application have, in many ways, contributed greatly to meeting global food demands. However, aside from the positive effects of mineral fertilizers, their excessive application to soil produces large amounts of pollutants that affect environmental sustainability. This necessitates the study of the major mineral fertilizer elements (nitrogen (N), phosphorus (P), and potassium (K)), the forms in which they are applied to soil, and their chemistry/reactions in soil. Here, we reviewed the forms of different N, P, and K mineral fertilizers to provide current knowledge on their constituents, the chemistry of N, P, and K in soil to understand the reactions they undertake in soil, the efficient methods of fertilizer application for environmental sustainability, the effects of mineral fertilizer loss to the environment, and improved fertilization technologies for environmental sustainability. Nanofertilizers are a promising technology for sustainable agricultural production and are discussed in detail in this review.
The elucidation of the ideal coordination environment of a catalytic site has been at the heart of catalytic applications. Herein, we show that the water oxidation activities of catalytic cobalt ...sites in a Prussian blue (PB) structure could be tuned systematically by decorating its coordination sphere with a combination of cyanide and bidentate pyridyl groups. K0.1Co(bpy)2.9Fe(CN)62 (Cobpy–Fe), K0.2Co(phen)2.8Fe(CN)62 (Cophen–Fe), {Co(bpy)23Fe(CN)62}Fe(CN)61/3 (Cobpy2–Fe), and {Co(phen)23Fe(CN)62}Fe(CN)61/3 Cl0.11 (Cophen2–Fe) were prepared by introducing bidentate pyridyl groups (phen: 1,10-phenanthroline, bpy: 2,2′-bipyridine) to the common synthetic protocol of Co–Fe Prussian blue analogues. Characterization studies indicate that Cobpy2–Fe and Cophen2–Fe adopt a pentanuclear molecular structure, while Cobpy–Fe and Cophen–Fe could be described as cyanide-based coordination polymers with lower-dimensionality and less crystalline nature compared to the regular Co–Fe Prussian blue analogue (PBA), K0.1Co2.9Fe(CN)62 (Co–Fe). Photocatalytic studies reveal that the activities of Cobpy–Fe and Cophen–Fe are significantly enhanced compared to those of Co–Fe, while molecular Cobpy2–Fe and Cophen2–Fe are inactive toward water oxidation. Cobpy–Fe and Cophen–Fe exhibit upper-bound turnover frequencies (TOFs) of 1.3 and 0.7 s–1, respectively, which are ∼50 times higher than that of Co–Fe (1.8 × 10–2 s–1). The complete inactivity of Cobpy2–Fe and Cophen2–Fe confirms the critical role of aqua coordination to the catalytic cobalt sites for oxygen evolution reaction (OER). Computational studies show that bidentate pyridyl groups enhance the susceptibility of the rate-determining Co(IV)-oxo species to the nucleophilic water attack during the critical O–O bond formation. This study opens a new route toward increasing the intrinsic water oxidation activity of the catalytic sites in PB coordination polymers.
High food demand for the world's teeming population necessitates the intensification of crop production in modern agriculture, which requires the extensive use of synthetic fertilizers for higher ...crop yield. The excessive use of chemical fertilizers, despite the high nutrients contents and ability to grow crops faster, discovered to be dangerous to the health and environment besides polluting the groundwater and atmosphere in the future. The alternative to these, biofertilizers arose today due to their attributes towards eco-friendly, cost-effective, and easy to apply in the agricultural field. Biofertilizers are a batch of diverse microorganisms, which can induce plant growth-promotion activities along with soil health, even under abiotic stress conditions. Biofertilizers maybe plant growth-promoting rhizobacteria, arbuscular mycorrhizal fungi, and as well as the consortia of other beneficial microbes. Biofertilizers can sustain plant growth performance, even in a challenging environment. The performance of perfect-candidate-biofertilizer in the agricultural field depends on crop type, properties of inoculants, technical background, and environmental condition. Biofertilizers can, directly or indirectly, help in attaining food security compared to the harmful effect of chemical fertilizers. A direct mechanism of Biofertilizers refers to phyto-stimulation and nutrient mobility, while an indirect mechanism poses bio-control activity. Direct mechanisms involve phytohormone production and phosphate, potassium, zinc, etc. solubilization. While, indirect-mechanism is HCN production, siderophore production, antibiotic production, etc. The present review elucidates the diversity of microbial inoculants (biofertilizers), their impacts on agricultural production through rising soil fertility, and overall crop yield. In line with related literature worked out by different researchers.
While antiretroviral therapy (ART) coverage for pregnant women has undergone steady scale-up, Nigeria's final mother- to-child transmission of HIV (MTCT) rate remains unacceptably high at 10%. This ...study aimed to determine final outcomes (MTCT rates) and their correlates among HIV-exposed infants (HEI) in nine states and the Federal Capital Territory, Nigeria.
This retrospective, cross-sectional study was conducted at 96 primary, secondary and tertiary health facilities supported by the Institute of Human Virology Nigeria. Data was abstracted for a birth cohort of HEI born between October 30, 2014 and April 30, 2015 whose 18-24 month final outcome was assessed by October 30, 2016. Only infants with a six-week first DNA PCR result, and a rapid HIV antibody test result at age 18 to 24 months were included. Multivariate logistic regression (adjusted odds ratios aORs) evaluated for predictors of HIV positivity at ≥18 months.
After testing at ≥18 months, 68 (2.8%) of the 2,405 exposed infants in the birth cohort were HIV-positive. After a minimum of 18 months of follow-up, 51 (75%) HIV-positive infants were alive on ART; 7 (10%) had died, 5 (7.3%) were lost to follow-up and 5 (7.3%) were transferred out. Rural maternal residence, lack of maternal ART/ARV prophylaxis, mixed infant feeding and infant birth weight less than 2.5 kg correlated with an HIV-positive status for infant final outcomes.
The final HIV positivity rate of 2.8% is encouraging, but is not population-based. Nevertheless, supported by our findings, we recommend continued programmatic focus on early access to quality prenatal care and maternal ART for pregnant women, especially for women living with HIV in rural areas. Furthermore, implementation of nationwide sensitization and education on six-months' exclusive infant breastfeeding with concurrent maternal ART should be strengthened and sustained to reduce MTCT rates.
Location preference is a repeatedly debated subject in urban land economics. By and large, these deliberations are either empirical or theoretical in nature. A sizeable number of the previous studies ...tackle the question of most favorable location provisional on a certain set of constrictions. Moreover, other studies are dedicated to elucidating the nature (worth) of a real property at a particular location. Nevertheless, the problem of ascertaining the indicators that influence real property price is general to both sets of studies. The current body of knowledge on the impact of transportation infrastructure on real estate prices is diverse in its outcome and result with particular reference to degree or extent of impact as well as bearing, ranging from a negative to an unimportant or a positive effect. On the literature results, multiple spatial lag variables were found to be statistically significant signifying that a number of features or attributes of adjoining residential accommodations have significant influence on the subject residential property's value. Whereas the largest part of earlier hedonic price empirical studies considered only selected factors (such as, positive as well as negative impacts of single transportation mode or means, positive or else negative impacts of multiple transportation modes) into account, the majority of recent empirical studies, however, considered all these key determinants, factors and indicators into consideration for analyzing joint impacts of transportation facility. Through considerable strategy, policy in addition to planning or forecasting implications underlying the association between transit oriented developments and real estate values and the difference between previous studies' outcomes and results, there is a strong necessity and requirement for further study and analysis to ascertain an advanced, reliable in addition to dependable level of conclusiveness.
The effective modelling of high-dimensional data with hundreds to thousands of features remains a challenging task in the field of machine learning. This process is a manually intensive task and ...requires skilled data scientists to apply exploratory data analysis techniques and statistical methods in pre-processing datasets for meaningful analysis with machine learning methods. However, the massive growth of data has brought about the need for fully automated data analysis methods. One of the key challenges is the accurate selection of a set of relevant features, which can be buried in high-dimensional data along with irrelevant noisy features, by choosing a subset of the complete set of input features that predicts the output with higher accuracy comparable to the performance of the complete input set. Kohonen’s self-organising neural network map has been utilised in various ways for this task, such as with the weighted self-organising map (WSOM) approach and this method is reviewed for its efficacy. The study demonstrates that the WSOM approach can result in different results on different runs on a given dataset due to the inappropriate use of the steepest descent optimisation method to minimise the weighted SOM’s cost function. An alternative feature weighting approach based on analysis of the SOM after training is presented; the proposed approach allows the SOM to converge before analysing the input relevance, unlike the WSOM that aims to apply weighting to the inputs during the training which distorts the SOM’s cost function, resulting in multiple local minimums meaning the SOM does not consistently converge to the same state. We demonstrate the superiority of the proposed method over the WSOM and a standard SOM in feature selection with improved clustering analysis.
People living with HIV (PLHIV) constantly need to address social issues such as the cost of accessing care, stigma, and lack of social support which impacts on their level of adherence to clinic ...visits or antiretroviral treatment leading to adverse health outcomes. This study examined the social barriers in accessing care by clients who returned to care after transient loss to follow-up.
This study was a cross-sectional survey of PLHIV from 99 US CDC PEPFAR-supported HIV clinics located in 10 of Nigeria's 36 states and Federal Capital Territory, who were momentarily lost to follow-up but returned to care after tracking. Demographic and social factors at bivariate and multivariate level were analyzed to determine the predictors of difficulty in accessing HIV clinics.
Of the 7483 clients tracked, 1386 (18.5%) were confirmed to be in care, 2846 (38.2%) were lost to follow-up (LTFU), 562 (7.5%) returned to care, 843 (11.2%) discontinued care, 827 (11.1%) transferred out to other facilities for care, 514 (6.8%) had died while 505 (6.7%) could not be reached by phone or located at their addresses. 438 out of the 562 (78%) returnee PLHIV gave consent and participated in the study. 216 out of the 438 (50%) clients who returned to care were transiently lost to follow-up because they had difficulty accessing their HIV clinic. Also, 126/438 (29%) of returnee PLHIV were previously lost to follow-up. Difficult access to a HIV clinic was significantly influenced by prior LTFU (OR 2.5 95% CI 1.3-4.8, p = 0.008), history of being stigmatized (OR 2.1 95% CI 1.1-3.8, p = 0.02), lack of social or financial support (OR 2.8 95% CI 1.3-6.0, p = 0.01) and perceived in-adequate healthcare workers support (OR 3.8 95% CI 1.2-11.2, p = 0.02). Age (p = 0.218) and gender (p = 0.771) were not significant determinants of difficult access to an HIV clinic.
Stigma, lack of support and prior loss to follow-up event are essential factors affecting retention in care. Social constructs such as home-based visits, community-based care services, transportation subsidies, and robust strong social systems should be built into HIV service delivery models to improve retention in care of people on HIV treatment. The authors advocate for further studies on how differentiated care models impact on retention of patients in care.
This paper investigates the application of a novel method for classification called Feature Weighted Self Organizing Map (FWSOM) that analyses the topology information of a converged standard Self ...Organizing Map (SOM) to automatically guide the selection of important inputs during training for improved classification of data with redundant inputs, examined against two traditional approaches namely neural networks and Support Vector Machines (SVM) for the classification of EEG data as presented in previous work. In particular, the novel method looks to identify the features that are important for classification automatically, and in this way the important features can be used to improve the diagnostic ability of any of the above methods. The paper presents the results and shows how the automated identification of the important features successfully identified the important features in the dataset and how this results in an improvement of the classification results for all methods apart from linear discriminatory methods which cannot separate the underlying nonlinear relationship in the data. The FWSOM in addition to achieving higher classification accuracy has given insights into what features are important in the classification of each class (left and right-hand movements), and these are corroborated by already published work in this area.
A negative status following confirmatory Early Infant Diagnosis (EID) is the desired pediatric outcome of prevention of Mother to Child Transmission (PMTCT) programs. EID impacts epidemic control by ...confirming non-infected HIV-exposed infants (HEIs) and prompting timely initiation of ART in HIV-infected babies which improves treatment outcomes.
We explored factors associated with EID outcomes among HEI in North-Central Nigeria.
This is a cross-sectional study using EID data of PMTCT-enrollees matched with results of HEI's dried blood samples (DBS), processed for DNA-PCR from January 2015 through July 2017. Statistical analyses were done using SPSS version 20.0 to generate frequencies and examine associations, including binomial logistic regression with p < 0.05 being statistically significant.
Of 14,448 HEI in this analysis, 51.8% were female and 95% (n = 12,801) were breastfed. The median age of the infants at sample collection was 8 weeks (IQR 6-20), compared to HEI tested after 20 weeks of age, those tested earlier had significantly greater odds of a negative HIV result (≤ 6 weeks: OR = 3.8; 6-8 weeks: OR = 2.1; 8-20 weeks: OR = 1.5) with evidence of a significant linear trend (p < 0.001). Similarly, HEI whose mothers received combination antiretroviral therapy (cART) before (OR = 11.8) or during the index pregnancy (OR = 8.4) had significantly higher odds as compared to those whose mothers did not receive cART. In addition, HEI not breastfed had greater odds of negative HIV result as compared to those breastfed (OR = 1.9).
cART prior to and during pregnancy, earlier age of HEI at EID testing and alternative feeding other than breastfeeding were associated with an increased likelihood of being HIV-negative on EID. Therefore, strategies to scale-up PMTCT services are needed to mitigate the burden of HIV among children.
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