The urban poor residents in South Africa are over time known for imbalance and inadequate housing amidst recent concern of shock in food production. In studying this peculiar problem, this study investigates the cointegration and long-run equilibrium relationship of population growth, crop production, and the housing price in the country. Empirically, a quarterly data from 1975:Q1 to 2015:Q4 is employed using the conventional Autoregressive Distributed Lag. The investigation shows strong significant evidence of cointegration and a quarterly speed of adjustment of 17.2% to long run in the system. Also, as the population grows, a decline in house price index is experienced in the long run. Although unusual, adequate and sustainable housing plan, demand-supply dynamics, in respect to a country’s population expansion could posit observation. But, in the short run, a strongly significant positive association is observed. It shows further that positively short-run and long-run relationships significantly exist between crop production and house price index. In reality, caution is essential in the introduction of land redistribution policy to avoid hampering the housing policies and 2030 housing target of the government.

Freshwater lakes provide critical ecological services to the local ecosystem. However, many of them are facing serious challenges, such as ecosystem degradation and water contamination, due to irrational water utilization and a lack of effective management. Under such a circumstance, it is crucial to examine the ecosystem services of freshwater lakes and uncover the driving forces so that appropriate protection policies can be raised. This study aims to fill such a research gap by employing an emergy accounting method. A case study of Erhai Lake (the second largest freshwater lake in Yunnan province, southwest China) was conducted for the period of 2001–2015. Driving forces that affect ecosystem services were analyzed by using Logarithmic Mean Divisia Index (LMDI). Results show that the total ecosystem services of Erhai Lake were reduced from 334.03E + 18 sej in 2001 to 274.37E + 18 sej in 2015. This was caused by the obvious decline of regulating services and supporting services, far exceeding the increase of provisioning services and cultural services. In 2015, two types of increased services that benefit human life in the market became the primary services of Erhai Lake. And their proportions were far beyond the two reduced ones that were overlooked due to their public and free attributes. The key driving forces include economic scale factor (∆EES), the fast and intensive economic activities. This development was at the cost of environmental degradation based upon the analysis of emergy benefit factor (∆EEB). Finally, several suggestions are presented. This study provides valuable insights to understand ecosystem services of freshwater lakes so that a sustainable development pathway can be found to protect such freshwater lakes.

In the present study, the influence of cadmium, copper, and lead on two enzymes often used as biomarkers in toxicological analysis was investigated. Bees were fed with 1 M sucrose solution containing 10-fold serial dilutions of CuCl₂ (1000 mg L⁻¹, 100 mg L⁻¹, and 10 mg L⁻¹), CdCl₂ (0.1 mg L⁻¹, 0.01 mg L⁻¹, and 0.001 mg L⁻¹), or PbCl₂ (10 mg L⁻¹, 1 mg L⁻¹, and 0.1 mg L⁻¹) during 48 h. Our results showed that the total glutathione S-transferase activity was not changed under the influence of cadmium and lead, and it was decreased with the highest concentration of copper. The level of gene expression of the three analyzed classes of glutathione S-transferase was significantly increased with increasing concentrations of copper and cadmium. Lead did not cause significant changes in glutathione S-transferase activity and gene expression, while it showed biphasic effect on acetylcholinesterase activity: lower concentration of lead, 0.1 mg L⁻¹ inhibited and higher dose, 10 mg L⁻¹ induced acetylcholinesterase activity in honey bees. Furthermore, our results showed a significant decrease of the acetylcholinesterase activity in honey bees treated with 0.001 and 0.01 mg L⁻¹ CdCl₂. Our results indicate the influence of cadmium, copper, and lead on GST and AChE in the honey bees. These results form the basis for future research on the impact of metallic trace element pollution on honey bees.

Bioconcentration factors (BCF) for regulatory purposes are usually determined by fish flow-through tests according to technical guidance document OECD 305. Fish bioconcentration studies are time consuming, expensive, and use many laboratory animals. The aim of this study was to investigate whether the freshwater amphipod Hyalella azteca can be used as an alternative test organism for bioconcentration studies. Fourteen substances of different hydrophobicity (log Kₒw 2.4–7.6) were tested under flow-through conditions to determine steady state and kinetic bioconcentration factors (BCFₛₛ and BCFₖ). The results were compared with fish BCF estimates for the same substances described in the literature to show the relationship between both values. Bioconcentration studies with the freshwater amphipod H. azteca resulted in BCF estimates which show a strong correlation with fish BCF values (r² = 0.69). Hyalella BCF values can be assessed in accordance with the regulatory B criterion (BCF > 2000, i.e., REACH) and thereby enable the prediction of B or non-B classification in the standard fish test. Therefore, H. azteca has a high potential to be used as alternative test organism to fish for bioconcentration studies.

The present study describes the experimental and numerical analysis of the combustion and emission characteristics of CI engine operated with diesel-butanol blends. Experiments were carried with neat diesel fuel (i.e., Bu00) and its blends of n-butanol, 10%, 20% and 30% by volume (Bu10, Bu20 and Bu30) at a constant speed and rated load. From the experimental results, it is observed that CO, NOₓ and smoke emissions decreased, whereas the unburned hydrocarbon (UBHC) emission increased with increasing butanol content, as compared to Bu00. From the experimental analysis, it is also observed that Bu20 blend gives higher brake thermal efficiency (BTE) and lower brake specific energy consumption (BSEC) as compared to Bu00, Bu10 and Bu30, but produces higher UBHC. In order to decrease the UBHC emission, different piston bowl geometries were analysed using simulation studies. The combustion and emission characteristics of the CI engine operating with Bu20 blend for three different piston bowl geometries viz., hemispherical combustion chamber (HCC), shallow combustion chamber (SCC) and toroidal combustion chamber (TCC), were studied using CONVERGE CFD code. The simulation model was validated with experimental results of the baseline engine configuration (HCC) for diesel fuel as well as Bu20 blend. The results showed that there is a significant reduction in UBHC and improvement of performance for SCC and TCC piston geometry compared to HCC piston geometry. However, a slight increment of NOₓ emissions was observed.

Hydroponic experiments were conducted to investigate the role of different root plaque formation on oxytetracycline (OTC) uptake/translocation by rice seedlings (Oryza sativa L.) and solution–OTC elimination at two initial OTC concentrations (10 and 30 mg L⁻¹). The results indicated OTC accumulation in rice was always in the order root surface > shoot > inside root whether plaques were formed or not. It demonstrated that Fe–Mn–Mt (montmorillonite) treatment was easier to promote significantly (p < 0.05) OTC accumulation in the underground part (root surface and inside root) and decrease significantly (p < 0.05) OTC translocation from the root to the shoot in rice compared to no plaque treatments (CK), especially for OTC 30 mg L⁻¹ level with the lowest shoot–OTC accumulation in Fe–Mn–Mt treatment. Plaque treatments increased half-life of solution–OTC elimination in the order Fe–Mn–Mt > Fe–Mn > Fe > CK, which was caused mainly by OTC degradation from Fe²⁺-binding influence in solution, not by the enhancement of OTC accumulation on the root surface and inside root. And solution–OTC elimination increased with decreasing initial OTC concentrations, the drop of Fe²⁺ and the increment of Fe³⁺ and pH during the experiment. These findings are useful for reducing OTC accumulation and translocation in rice aboveground parts and eliminating OTC contamination in agricultural environment simultaneously through complicated plaque formation under higher OTC concentration exposure (30 mg L⁻¹) in the future design.

Management of organic biomedical waste is a global quandary, and it is becoming difficult to confront day by day. Conversion of organic biomedical waste into fertilizer is of great concern. In the present research, organic biomedical waste samples (blood swabs, dressing swabs, and used cotton) were collected then after cow dung was collected in sterile container and immediately transported to the laboratory and screened for any gastrointestinal infection by using routine microscopy for intestinal parasitic infection, routine bacterial culture, and fecal occult blood for any intestinal bleeding. Then after, the pure culture of organisms and fungus were prepared, and further samples were subjected to degradation for 288 h by using various organisms and fungus. Then after, the specific quantity of biomedical waste was subjected for incineration. The physicochemical parameters of biomedical waste samples were analyzed. Then treated samples were mixed with soil to confirm a role as potential fertilizer. Then after, tomato plantation was done and phytochemical parameters of tomato plant were analyzed. This study states that organic biomedical waste produces a sanitary and stable fertilizer.

Flood plains can make a significant contribution to food security due to their rich agricultural and aquaculture potentials but the misuse of pesticides in these ecosystems may seriously threaten their sustainability. We have assessed the risk of commonly used pesticides by rice and vegetable farmers on two major streams in the Ndop flood plain in Cameroon using the PRIMET model. Thirty pesticide formulations were identified containing 17 active ingredients belonging to fungicides (7), herbicides (3), and insecticides (7). Out of these, five posed acute and/or chronic risks to the streams. Chlorpyriphos-ethyl (ETR = 655), chlorothalonil (ETR = 250), and cypermethrin (ETR = 190) posed a definite acute risk to both streams. These pesticides also posed possible chronic risks with cypermethrin also posing a definite chronic risk (ETR = 1658) to fish in one of the streams. Mancozeb (ETR = 2.2) and λ-cyhalothrin (ETR = 2.8) posed a possible acute risk to both streams. It was interesting to note that most pesticides, including some of those that posed a risk, were applied at lower doses than their respective recommended doses. Differences in ETRs were also observed in the two streams with higher values occurring in the stream having a lower concentration of suspended solids. The higher velocity of the Ngwala-Mesaw stream did not affect the acute risk posed by pesticides. Pesticide toxicity was an important determinant in the risk posed and we recommend that appropriate mitigation measures be put in place to reduce the risk of these pesticides such as the implementation of an appropriate buffer zone between the edge of field and water body.

In order to understand the mechanism of the difference of Cd absorption and Cd enrichment in different ryegrass varieties, pot experiment was conducted to study on the response of two varieties of ryegrass (Bond and Abbott) to Cd stress as well as the differences of Cd uptake and expression of MT family genes and NRAMP2. Results showed that root dry weights of two varieties and shoot dry weights of Abbott increased first and then decreased with the increase of Cd level in soil. When exposed to 75 mg kg⁻¹ Cd, shoot dry weight and plant dry weight of Abbott both reached maximum values (10.92 and 12.03 g pot⁻¹), which increased by 11.09 and 10.67% compared with the control, respectively. Shoot dry weight and plant dry weight of Bond decreased with the increase of Cd level in soil. When the Cd level in soil was 75 mg kg⁻¹, shoot Cd concentrations of the two varieties were 111.19 mg kg⁻¹ (Bond) and 133.69 mg kg⁻¹ (Abbott), respectively, both of which exceeded the critical value of Cd hyperaccumulator (100 mg kg⁻¹). The expression of MT gene family and NRAMP2 in the leaf of Bond variety significantly increased at the Cd level of 75 mg kg⁻¹ and reached maximum value (except MT2C) at Cd level of 150 mg kg⁻¹. The expression of MT gene family in the stem of Bond variety showed a double-peak pattern, while the expression of NRAMP2 was a single-peak pattern. The expression of MT gene family and NRAMP2 in Abbott variety was consistent with single-peak pattern. The expression of MT gene family and NRAMP2 in leaf both significantly increased at Cd level of 150 mg kg⁻¹, while that in stem and root significantly increased at Cd level of 75 mg kg⁻¹. For both varieties of ryegrass, the expression amount of MT family genes and Nramp2 in leaf was higher than that in root and stem, indicating the Cd tolerance of ryegrass can be improved by increasing the expression levels of MT family genes and Nramp2 in stem and root. There was significant genotypic difference in the expression of MT gene family and NRAMP2 between the two varieties of ryegrass, and the expression of MT gene family and NRAMP2 in leaves and stems of Bond variety was higher than that in Abbott variety, while the expression of MT gene family and NRAMP2 in roots of Abbott variety was higher than that in Bond variety. The two gene families investigated in this study may be closely related to Cd uptake, but not related to Cd transport from root to leaf and Cd enrichment in shoot.

The present study aimed to determine the level of iron and calcium in the seminal plasma of men with different fertility potentials and to examine its relationship with oxidative stress. Seventy-nine sub-fertile patients with asthenoteratozoospermia (AT), n 27; teratoleucozoospermia (TL), n 20; teratozoospermia (Terato), n 32; and 29 healthy donors were included. The ability of spermatozoa to produce reactive oxygen species (ROS) was evaluated by using nitroblue tetrazolium (NBT) staining. The lipid peroxidation end product, malondialdehyde (MDA), and the trace element levels (iron and calcium) were measured spectrophotometrically. Iron and calcium concentrations in seminal plasma of the patient groups were significantly more elevated than the normal group. Nevertheless, both calcium and iron showed strong negative correlations with the total sperm motility and normal sperm morphology, but only iron was positively and significantly associated with multiple anomalies index and seminal leucocyte concentration. On the other hand, the rates of MDA and ROS production in semen were significantly higher in the three abnormal groups than in controls. These two oxidative stress biomarkers were significantly associated with the percentage of atypical forms in semen. However, only semen ROS level was significantly associated with the decreased sperm motility and the sperm leucocytes concentration. Meanwhile, there are positive correlations between seminal iron and calcium content and the studied oxidative stress biomarkers. Oxidative stress and trace element excess are implicated in low sperm quality. Iron and calcium might be the mediators of the effects of oxidative damage and induces lipid peroxidation.