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The widespread proliferation of water hyacinth (Eichhornia crassipes) in aquatic ecosystems has raised significant ecological, environmental, and socioeconomic concerns globally. These concerns include reduced biodiversity, impeded water transportation and recreational activities, damage to marine infrastructure, and obstructions in power generation dams and irrigation systems. This review critically evaluates the challenges posed by water hyacinth (WH) and investigates potential strategies for converting its biomass into value-added agricultural products, specifically nanonutrients-fortified, biochar-based, green fertilizer. The review examines various methods for producing functional nanobiochar and green fertilizer to enhance plant nutrient uptake and improve soil nutrient retention. These methods include slow or fast pyrolysis, gasification, laser ablation, arc discharge, or chemical precipitation used for producing biochar which can then be further reduced to nano-sized biochar through ball milling, a top-down approach. Through these means, utilization of WH-derived biomass in economically viable, eco-friendly, sustainable, precision-driven, and smart agricultural practices can be achieved. The positive socioeconomic impacts of repurposing this invasive aquatic plant are also discussed, including the prospects of a circular economy, job creation, reduced agricultural input costs, increased agricultural productivity, and sustainable environmental management. Utilizing WH for nanobiochar (or nano-enabled biochar) for green fertilizer production offers a promising strategy for waste management, environmental remediation, improvement of waterway transportation infrastructure, and agricultural sustainability. To underscore the importance of this work, a metadata analysis of literature carried out reveals that an insignificant section of the body of research on WH and biochar have focused on the nano-fortification of WH biochar for fertilizer development. Therefore, this review aims to expand knowledge on the upcycling of non-food crop biomass, particularly using WH as feedstock, and provides crucial insights into a viable solution for mitigating the ecological impacts of this invasive species while enhancing agricultural productivity.

In this study, managanese dioxide nanoparticles (MnO2-NP) was synthesized. Raphia hookeri seed was used as a bioreductant for the synthesis of MnO2-NPs. The biosynthesized MnO2-NPs was investigated for their reaction, structure and morphology. The MnO2-NPs was characterized using the UV-Visible spectrophotometry, Fourier Transform Infrared Spectrophotometry (FTIR), Energy Dispersive Spectrometry (EDX), Powdered X-ray Diffractometry (PXRD), Scanning electron microscpopy (SEM) and Transmission Electron Microscopy (TEM). UV-Visible spectra revealed that MnO2-NPs showed maximum 421nm respectively. FTIR results showed prominent reactive functional groups for hydroxyl (-OH) and carbonyl (-C=O). The EDX results revealed the elemental composition in percentages of the elements in the nanoparticles. PXRD revealled that the manganese dioxide nanoparticle is in a crystaline state. The morphology of the synthesized nanoparticle was found irregular and with porous surface for SEM. The average particle size of the nanoparticles as characterized by TEM was found to be 3.92 nm.

A combination of rapid population growth, climate change, and environmental degradation have placed immense pressure on global food sources and increased food security concerns especially in developing economies like those of African countries. Notably, efforts to produce food for the rising human population have continued to burden arable lands across the globe, necessitating heavy use of chemical fertilizers to increase crop yield. While the widespread use of conventional fertilizers has indeed enhanced crop productivity, its sustainability is threatened by rapid soil degradation and rising environmental concerns resulting from chemical compound accumulation across several ecosystems. The invention of nanotechnology, which is the synthesis and manipulation of materials at the nanometer (1 to 100 nm) range, promises potential solutions to these agricultural sustainability challenges. Specifically, theoretical, and experimental research on nanofertilizers have highlighted significant potential for their employment in sustainable farming practices. The current review examines the benefits conferred by the delivery of nutrients to plants at the nanoscale, outlining the progress, challenges, and opportunities for adopting this emerging technology by African countries, and highlighting future perspectives and areas of possible collaborations globally.

Aim: The aim of this study was to investigate the association of serum total Hcy (tHcy) levels with various demographic, clinical and genetic characteristics in healthy Greek adults. Methods: Anthropometric characteristics (height, weight), systolic and diastolic blood pressure, complete blood count and biochemical assessments, were recorded and measured among 383 Greek adults (199 men). Serum folate, Cobalamin (Cbl) and tHcy levels were determined using immunoassays methods. The MTHFR C677T and A1298C gene polymorphisms were genotyped using polymerase chain reaction and reverse hybridization. Results: MTHFR C677T gene polymorphism, serum folate and Cbl levels were correlated with serum tHcy levels independently. The individuals with 677TT genotype had significantly higher serum tHcy levels than individuals with 677 CC or CT genotypes. Regarding the MTHFR C677T gene polymorphism, the existence of the T allele was associated with statistically significantly lower serum folate and higher serum tHcy levels than C allele. Regarding the MTHFR A1298C gene polymorphism, the existence of the C allele was associated with statistically significant lower serum tHcy levels than A allele. Furthermore, there was no significant correlation between the serum tHcy levels and demographic (except age) or clinical characteristics (sex, BMI, smoking status, SBP, DBP, HGB, HCT, TC, TG, HDL-C, LDL-C, TC/HDL-C). Conclusions: Serum tHcy levels are influenced by the existence of MTHFR C677T gene polymorphism (mainly 677TT genotype), serum folate and Cbl levels. Individuals with hyperhomocysteinemia should be further investigated for the existence of MTHFR C677T gene polymorphism, with the aim to determine the suitable treatment.

Autoimmune diseases, which affect approximately 5% of human population, are a range of diseases in which the immune response to self-antigens results in damage or dysfunction of tissues. Recent genome wide association studies (GWAS) have successfully identified novel autoimmune disease-associated loci, with many of them shared by multiple disease-associated pathways but much of the genetics and pathophysiological mechanisms remain still obscure. Considering that most of the potential causal variants are still unknown, many studies showed that the missense variant rs35667974 at interferon-induced with helicase C domain 1 (IFIH1) gene is protective for type 1 diabetes (T1D), psoriasis (PS) and psoriatic arthritis (PsA). Recently, this variant was found to be also associated with ankylosing spondylitis (AS), Crohn’s disease (CD) and ulcerative colitis (UC). The IFIH1 gene encodes a cytoplasmic RNA helicase otherwise known as melanoma differentiation-associated 5 (MDA5) that recognizes viral RNA and is involved in innate immunity through recognition of viral RNA. In the present study we sought to investigate the association of the rare rs35667974 variant of IFIH1 gene, which resides in exon 14 and changes a conserved isoleucine at position #923 to valine, in the development of various autoimmune diseases and give a reason for the selectivity affecting different autoimmune diseases. Evolutionary studies and three-dimensional (3 D) homology modelling were employed on the MDA5 protein product, through its association with dsRNA, recognition factor controlling cytokine and chemokine signalling, to investigate the protective role of the MDA5 variant for certain autoimmune diseases.

Leptospirosis is a neglected disease of man and animals that affects nearly half a million people annually and causes considerable economic losses. Current human vaccines are inactivated whole-cell preparations (bacterins) of Leptospira spp. that provide strong homologous protection yet fail to induce a cross-protective immune response. Yearly boosters are required, and serious side-effects are frequently reported so the vaccine is licensed for use in humans in only a handful of countries. Novel universal vaccines require identification of conserved surface-exposed epitopes of leptospiral antigens. Outer membrane β-barrel proteins (βb-OMPs) meet these requirements and have been successfully used as vaccines for other diseases. We report the evaluation of 22 constructs containing protein fragments from 33 leptospiral βb-OMPs, previously identified by reverse and structural vaccinology and cell-surface immunoprecipitation. Three-dimensional structures for each leptospiral βb-OMP were predicted by I-TASSER. The surface-exposed epitopes were predicted using NetMHCII 2.2 and BepiPred 2.0. Recombinant constructs containing regions from one or more βb-OMPs were cloned and expressed in Escherichia coli. IMAC-purified recombinant proteins were adsorbed to an aluminium hydroxide adjuvant to produce the vaccine formulations. Hamsters (4-6 weeks old) were vaccinated with 2 doses containing 50 – 125 μg of recombinant protein, with a 14-day interval between doses. Immunoprotection was evaluated in the hamster model of leptospirosis against a homologous challenge (10 – 20× ED50) with L. interrogans serogroup Icterohaemorrhagiae serovar Copenhageni strain Fiocruz L1-130. Of the vaccine formulations, 20/22 were immunogenic and induced significant humoral immune responses (IgG) prior to challenge. Four constructs induced significant protection (100%, P < 0.001) and sterilizing immunity in two independent experiments, however, this was not reproducible in subsequent evaluations (0 – 33.3% protection, P > 0.05). The lack of reproducibility seen in these challenge experiments and in other reports in the literature, together with the lack of immune correlates and commercially available reagents to characterize the immune response, suggest that the hamster may not be the ideal model for evaluation of leptospirosis vaccines and highlight the need for evaluation of alternative models, such as the mouse.

Ternary Cu2SnS3 (CTS) nanostructures were prepared via a simple solvothermal method using copper(II) dithiocarbamate and organotin(IV) dithiocarbamate as precursor complexes, and oleic acid as the capping agent at 220 °C. The concentration of the copper complex was varied in order to investigate the effect of the change in the concentration of the complex on the structural, morphological and optical properties of CTS particles. The nanoparticles were characterized by optical and structural techniques. Pure phase monoclinic Cu2SnS3 nanoparticles were obtained at equimolar concentration of the precursor complexes and mixed phases of Cu2SnS3 and Cu4SnS4 as the concentration of the copper complex increased. The nanoparticles (NPs) showed agglomerated spherical morphology and band gap energies in the range 1.0–1.5 eV. The redox responses of the CTS NPs modified screen plate carbon electrode (SPCE) was studied and the electrochemical parameters revealed that they possessed good electro-catalytic properties, indicating the potential of the material for further study in sensor applications.

Abstract Background Retinal diseases are common in dogs. Some hereditary retinal dystrophies in dogs are important not only because they lead to vision loss but also because they show strong similarities to the orthologous human conditions. Advances in in vivo non-invasive retinal imaging allow the capture of retinal cross-section images that parallel low power microscopic examination of histological sections. Spectral domain - optical coherence tomography (SD-OCT) allows the measurement of retinal layer thicknesses and gives the opportunity for repeat examination to investigate changes in thicknesses in health (such as changes with maturation and age) and disease (following the course of retinal degenerative conditions). The purpose of this study was to use SD-OCT to measure retinal layer thicknesses in the dog during retinal maturation and over the first year of life. SD-OCT was performed on normal beagle cross dogs from 4 weeks of age to 52 weeks of age. To assess changes in layer thickness with age, measurements were taken from fixed regions in each of the 4 quadrants and the area centralis (the region important for most detailed vision). Additionally, changes in retinal layer thickness along vertical and horizontal planes passing through the optic nerve head were assessed. Results In the four quadrants an initial thinning of retinal layers occurred over the first 12 to 15 weeks of life after which there was little change in thickness. However, in the area centralis there was a thickening of the photoreceptor layer over this time period which was mostly due to a lengthening of the photoreceptor inner/outer segment layer. The retina thinned with greater distances from the optic nerve head in both vertical and horizontal planes with the dorsal retina being thicker than the ventral retina. Most of the change in thickness with distance from the optic nerve head was due to difference in thickness of the inner retinal layers. The outer retinal layers remained more constant in thickness, particularly in the horizontal plane and dorsal to the optic nerve head. Conclusions These measurements will provide normative data for future studies.

Satellite rainfall products for landslide early warning prediction have been spotlighted by several researchers, in the last couple of decades. This study investigates the use of TRMM and ERA-Interim data, for the determination of rainfall thresholds and the prediction of precipitation, respectively, to be used for landslide early warning purposes at the Bogowonto catchment, Central Java, Indonesia. A landslide inventory of 218 landslides for the period of 2003–2016 was compiled, and rainfall data were retrieved for the landslide locations, as given by 6 ground stations, TRMM, and ERA-Interim data. First, rainfall data from the three different sources was compared in terms of correlation and extreme precipitation indices. Second, a procedure for the calculation of rainfall thresholds for landslide occurrence was followed consisting of four steps: i) the TRMM-based rainfall data was reconstructed for selected dates and locations characterized by landslide occurrence and non-occurrence; ii) the antecedent daily rainfall was calculated for 3, 5, 10, 15, 20 and 30 days for the selected dates and locations; iii) two-parameter daily rainfall-antecedent rainfall thresholds were calculated for the aforementioned dates; after analysis of the curves the optimum number of antecedent rainfall days was selected; and (iv) empirical rainfall thresholds for landslide occurrence were determined. The procedure was repeated for the entire landslide dataset, differentiating between forested and built-up areas, and between landslide occurrence in four temporal periods, in relation to the monsoon. The results indicated that TRMM performs well for the detection of very heavy precipitation and can be used to indicate the extreme rainfall events that trigger landslides. On the contrary, as ERA-Interim failed to detect those events, its applicability for LEWS remains limited. The 15-day antecedent rainfall was indicated to mostly affect the landslide occurrence in the area. The rainfall thresholds vary for forested and built-up areas, as well as for the beginning, middle and end of the rainy season.

Three Schiff base compounds, N1,N2-bis(3-nitrobenzylidene)phenylene diamine (NBBA), 2-methyl-N-(3-nitrobenzylidene)aniline (MNBA) and N-(2-chlorobenzylidene)-4-nitroaniline (CBNA) were synthesized, characterised and applied for the first time as potential mild steel (MS) corrosion inhibitors in 1 M HCl at 30 °C. Fourier transform infra-red (FTIR), 1H, 13C Nuclear magnetic resonance (NMR) and Mass spectrometry (MS) were used for the characterisation of the compounds. The electrochemical studies and evaluation of corrosion inhibition potency were achieved using potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) techniques. Density functional theory (DFT) calculations were further employed to describe the electronic distribution on the molecules and potential sites that aided corrosion inhibition. The results of the employed characterisation techniques confirmed the proposed structures of the compounds with the MS revealing the exact molecular mass of the compounds. Electrochemical results showed that the trend in inhibition efficiency of the three compounds was in the order: MNBA > NBBA > CBNA. MNBA recorded the highest inhibition efficiency at 100 ppm. Corrosion kinetics of the set of inhibitors was found to prefer the Langmuir adsorption isotherm with both physisorption and chemisorption mechanisms as revealed by ΔG values. In an effort to develop efficient corrosion inhibitors with non-toxic effect, low cost and multiple adsorption centres, these Schiff bases are presented.

Nutrient deficiency in food crops is seriously affecting human health, especially those in the rural areas, and nanotechnology may become the most sustainable approach to alleviating this challenge. There are several ways of fortifying the nutrients in food such as dietary diversification, use of drugs and industrial fortification. However, the affordability and sustainability of these methods have not been completely achieved. Plants absorb nutrients from fertilizers, but most conventional fertilizers have low nutrient use and uptake efficiency. Nanofertilizers are, therefore, engineered to be target oriented and not easily lost. This review surveys the effects of the addition of macro- and nanonutrients to soil, the interaction, and the absorption capability of the plants, the environmental effect and food content of the nutrients. Most reports were obtained from recent works, and they show that plants nutrients could be enriched by applying nanoparticulate nutrients, which are easily absorbed by the plant. Although there are some toxicity issues associated with the use of nanoparticles in crop, biologically synthesized nanoparticles may be preferred for agricultural purposes. This would circumvent the concerns associated with toxicity, in addition to being pollution free. This report, therefore, offers more understanding on the application of nanotechnology in biofortification of plant nutrients and the future possibilities offered by this practice. It also highlights some of the ills associated with the introduction of nanomaterials into the soil for crop’s improvement.

Functional and folding constraints impose interdependence between interacting sites along the protein chain that are envisaged through protein sequence evolution. Studying the influence of structure in phylogenetic models requires detailed and reliable structural models. Polysaccharide deacetylases (PDAs), members of the carbohydrate esterase family 4, perform mainly metal-dependent deacetylation of O- or N-acetylated polysaccharides such as peptidoglycan, chitin and acetylxylan through a conserved catalytic core termed the NodB homology domain. Genomes of Bacillus anthracis and its relative Bacillus cereus contain multiple genes of putative or known PDAs. A comparison of the functional domains of the recently determined PDAs from B. anthracis and B. cereus and multiple amino acid and nucleotide sequence alignments and phylogenetic analysis performed on these closely related species showed that there were distinct differences in binding site formation, despite the high conservation on the protein sequence, the folding level and the active site assembly. This may indicate that, subject to biochemical verification, the binding site-forming sequence fragments are under functionally driven evolutionary pressure to accommodate and recognize distinct polysaccharide residues according to cell location, use, or environment. Finally, we discuss the suggestion of the paralogous nature of at least two genes of B. anthracis, ba0330 and ba0331, via specific differences in gene sequence, protein structure, selection pressure and available localization patterns. This study may contribute to understanding the mechanisms under which sequences evolve in their structures and how evolutionary processes enable structural variations.

El espacio en cabina de una aeronave influye directamente en las capacidades de la tripulación a la hora de realizar su trabajo. La comodidad, el ambiente, Ia iluminacion, la forma en que se presenta toda Ia información de la aeronave en los instrumentos son algunos de los factores que son considerados en toda situación de vuelo. La metodología de diseiio preliminar de este espacio de cabina y su interacción con la tripulacion basada en procesos de diseño centrados en el ser humano, sera el principal topico de este artículo.

Synthesis of metallic and semiconductor nanoparticles through physical and chemical routes has been extensively reported. However, green synthesized metal nanoparticles are currently in the limelight due to the simplicity, cost-effectiveness and eco-friendliness of their synthesis. This study explored the use of aqueous leaf extract of Costus afer in the synthesis of silver nanoparticles (CA-AgNPs). The optical and structural properties of the resulting silver nanoparticles were studied using UV-visible spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Fourier transform infra–red spectrophotometer (FTIR). TEM images of the silver nanoparticles confirmed the existence of monodispersed spherical nanoparticles with a mean size of 20 nm. The FTIR spectra affirmed the presence of phytochemicals from the Costus afer leaf extract on the surface of the silver nanoparticles. The electrochemical characterization of a CA-AgNPs/multiwalled carbon nanotubes (MWCNT)-modified electrode was carried out to confirm the charge transfer properties of the nanocomposites. The comparative study showed that the CA-AgNPs/MWCNT-modified electrode demonstrated faster charge transport behaviour. The anodic current density of the electrodes in Fe(CN)6]4−/[Fe(CN)6]3− redox probe follows the order: GCE/CA-Ag/MWCNT (550 mA/cm2) > GCE/MWCNT (270 mA/cm2) > GCE (80 mA/cm2) > GCE/CA-Ag (7.93 mA/cm2). The silver nanoparticles were evaluated for their antibacterial properties against Gram negative (Escherichia coli, Klebsiella pneumonia, Pseudomonas aeruginosa) and Gram positive (Bacillus subtilis and Staphylococcus aureus) pathogens. The nanoparticles exhibited better inhibition of the bacterial strains compared to the precursors (leaf extract of Costus afer and silver nitrate). Furthermore, the ability of the nanoparticles to scavenge DPPH radicals at different concentrations was studied using the DPPH radical scavenging assay and compared to that of the leaf extract and ascorbic acid. The nanoparticles were better DPPH scavengers compared to the leaf extract and their antioxidant properties compared favorably the antioxidant results of ascorbic acid. The green approach to nanoparticles synthesis carried out in this research work is simple, non-polluting, inexpensive and non-hazardous.

Learner discipline is a problem in South African schools. The most serious aspect is addressing learner-discipline problems. Research has shown that teachers are at a loss for effective methods for maintaining discipline. The literature that does exist pertaining to methods of maintaining discipline, invariably enumerates a host of techniques in a ‘bag of tricks’ fashion: behaviouristic, like treating symptoms, that is, the behavioural manifestation rather than addressing the causes of that behaviour, paying no attention to the psychic dynamics and social context behind poor discipline. This is at variance with the fact that learner-discipline problems have a causal base which reaches far beyond the individual teacher–individual learner interaction. At the levels of the school, family and society, as well as at the level of the spiritual and social functioning of the child and how that might result in discipline problems, and how that should be taken into account when addressing learner discipline problems, a host of literature has been published in recent years. This article surveys this literature, synthesising it in a systematic way that shows a broader and more extensive way of approaching the issue of the problems of addressing learner discipline in South African schools. Although the problem of ill discipline in schools is not limited to or absent from schools that educate on biblical principles, the discussion in the literature occasionally ventures into a brief mention of how the problem could be approached from a holistic and integrated Christian perspective.

Malignant granular cell tumors are extremely rare, aggressive neoplasms displaying rapid growth and frequent associated metastatic disease. Excision and evaluation for metastatic disease are mandatory. We present a 54-year-old patient with a malignant granular cell tumor, treated with Mohs micrographic surgery. Cutaneous granular cell tumors are uncommon neoplasms, likely of perineural origin. Most follow a benign and uneventful course, with wide local excision being the treatment of choice (Enzinger, 1988). The malignant granular cell tumor is an extremely rare, aggressive variant, which provides a diagnostic challenge and management dilemma, especially with early presentation when it may be mistaken for other entities. There is also controversy regarding surgical management and follow-up of both benign and malignant granular cell tumors.

Thrombophilia, either congenital or acquired, has foremost consequences in the abdominal vessels. We review here the cases of patients admitted with abdominal vessel thrombosis over a five-year period. Our data focused on gender and age at diagnosis, site of thrombosis, previous thromboembolic events, underlying conditions, and family history. Investigations included measurement of protein C, protein S, activated PC resistance, and antithrombin, and screening for factor V Leiden, prothrombin G20210A, the C677T variant of the methylenetetrahydrofolate reductase gene, and V617F JAK2 mutation, r lupus anticoagulant, antiphospholipid antibodies and paroxysmal nocturnal hemospherinouria, and also serum folate, vitamin 12, and total homocysteine concentrations. Twenty-nine patients were admitted and 18 of their family members also underwent the same thrombophilia investigations. Eighteen patients (62.1%) presented with portal vein thrombosis (PVT), five patients (17.2%) with mesenteric vein thrombosis (MVT), four patients (13.8%) with splenic vein thrombosis (SVT), and two (6.9%) patients with hepatic vein thrombosis (HVT). There was a high incidence of congenital thrombophilia (37.9%), acquired thrombophilic conditions (27.6%), or both (20.7%). Sixteen of 18 patients with PVT, four of five patients with MVT, all four patients with SVT, and one of two patients with HVT had one or more thrombophilic risk factors. In 13.8% of the patients no underlying condition was identified. We concluded that thrombophilia may have major implications in the pathogenesis of abdominal vessel thrombosis in adult life, and a thorough thrombophilia investigation should be performed in all these patients.