The Covid-19 Pandemic: Limited Water Access and the Precarity of Women Fishers at Lake Kariba, Zimbabwe

Man-made reservoirs are constructed to meet certain purposes and Lake Kariba, Zimbabwe, was designed for hydroelectric power generation. However, it has developed other multiple uses, and the growth of fisheries on the lake has had a significant impact on the livelihoods of local communities. The declaration of Covid-19 as a pandemic in Zimbabwe in March 2020 was quickly followed by the imposition of national lockdowns with varying levels of severity up to the present day. This was done to curtail the spread of the disease, meanwhile enhancing the nation’s capacity in terms of acquiring testing kits, constructing more admission and quarantine centres as well as educating the people about ways to keep safe. In response to the calls by the government to monitor the movement of people and compliance of the lockdown rules, the Zimbabwe National Parks and Wildlife Management Authority (ZNPWMA), the governing body of the Lake Kariba fisheries, imposed rules that have significantly impacted the fishing communities at Lake Kariba. Both gillnet fishers and rod and line fishers have been impacted, but our focus here is on women rod and line fishers. Using the precarious livelihoods conceptual frameworks, we show how the changes in water management during the Covid-19 pandemic lockdowns has generated high levels of precariousness on the livelihoods of women at Kariba. We define precariousness as the condition of uncertainties brought to the women fishers by changes in water restrictions. The precarity of women was induced by several factors. For instance, the women fishers reported that restrictions to accessing fish in areas with high catches impacted them. They are also now obliged to pay exorbitant fishing fees in a way to discourage them to fish; they were frequently chased away from the Lake by ZNPWMA officers; they had limited amount of time to fish due to curfews; and failure to comply results in heavy fines imposed on them among other challenges. We show how these challenges interact with the current Zimbabwe socio-economic crisis to worsen the precariousness and vulnerability of women fishers at Lake Kariba. Data presented in this manuscript are based on participant observation and interviews with women fishers at Lake Kariba.

Applications of Chitosan-Alginate-Based Nanoparticles—An Up-to-Date Review

Chitosan and alginate are two of the most studied natural polymers that have attracted interest for multiple uses in their nano form. The biomedical field is one of the domains benefiting the most from the development of nanotechnology, as increasing research interest has been oriented to developing chitosan-alginate biocompatible delivery vehicles, antimicrobial agents, and vaccine adjuvants. Moreover, these nanomaterials of natural origin have also become appealing for environmental protection (e.g., water treatment, environmental-friendly fertilizers, herbicides, and pesticides) and the food industry. In this respect, the present paper aims to discuss some of the newest applications of chitosan-alginate-based nanomaterials and serve as an inception point for further research in the field.

The Engagement of Nineteenth-Century Scholars with Jirmānūs Farḥāt’s Baḥth al-Maṭālib: An Early Modern Textbook for Ottoman Schools

This article focuses on the engagement of three scholars of the nineteenth century, later to be called scholars of the nahḍa, with an Arabic grammar manual titled Baḥth al-maṭālib wa-ḥathth al-ṭālib (“The Pursuit of the Questions and the Encouragement of the Student”), supposedly written in 1705 by the Maronite monk Jibrīl (later Jirmānūs) Farḥāt (1670–1732). The scholars considered in this contribution are Aḥmad Fāris al-Shidyāq (d. 1887), Buṭrus al-Bustānī (d. 1883), and Saʿīd al-Khūrī al-Shartūnī (d. 1912). They engaged with this text by editing and printing it, and by making it available for use in Ottoman public schools. Through a close reading of representative excerpts from their printed editions, this article explores the three scholars’ philological engagement with Baḥth al-maṭālib and its multiple uses in nineteenth-century schools. The ways in which they worked on the text, it is argued, illustrate their different pedagogical approaches towards the teaching of the Arabic language.

Water quality analysis of Ribeirão São João in the Municiply of Porto Nacional – Tocantins / Análise da qualidade da água do Ribeirão São João no Município de Porto Nacional - Tocantins

Water is the source of life and an indispensable element of nature for human survival. Over the centuries, the available water resources have undergone constant crisis processes, especially when it comes to water pollution that affects its effectiveness for consumption. The monitoring of the water quality offers qualitative information about the water based on the parameters adopted in the CONAMA Resolution nº. 357/2005 and the calculation IQA NSF of the National Sanitation Foundation (APHA, 2005). The study about the water quality index aims to obtain information about the quality of the hydric resource available in Ribeirão São João in Porto Nacional - Tocantins, which has multiple uses such as: public supply, fishing, leisure, among others. The analysis undertaken to verify the quality of the water adopted procedures for analyzing the parameters of temperature, oxygen, pH, total nitrogen, total phosphorus, fecal coliforms, total solids and turbidity that occurred between the months of August and September 2021. The collection and analysis of water samples showed that the Ribeirão presents acceptable levels within the parameters established by the literature studied and infer that the water quality is considered average for the purposes of capitation and human consumption.

Evaluation of Dentin Microroughness and Composite Bond Strength After Multiple Uses of Diamond Burs

Using a bur multiple times to prepare dental structure may produce a smoother final surface on dentin than a new one. This superficial roughness may affect adhesion with resin-based materials by modifying the substrates’ characteristics. The aim of this study was to evaluate the effect of multiple uses of diamond burs on dentin’s superficial microroughness and bond strength with resin composite when using a self-etch adhesive. Diamond dental burs were used to simulate a preparation (dentin flat surface) on extracted third molars. Samples were distributed into groups according to burs’ number of previous uses as follows: 0, 1, 5 and 10. Scanning electron microscopy images at 70x, 350x, and 1000x were used to illustrate burs’ deformation. Each specimen’s dentin microroughness was measured three times to compare between experimental groups and the micro-shear bond strength test (n=15) was performed for the 0 and 10 uses groups using a universal adhesive in a self-etching mode. Diamond crystals wear and dislodgements were evident among groups where the burs were used more times. As the number of uses increased the mean microroughness of the dentin surface decreased with significant differences between the 0 and 10 uses groups. No statistical differences between experimental groups resulted from bond strength tests. When using a universal adhesive in a self-etching mode, the number of previous uses of a diamond bur seems to have no significant effect on dentin/resin composite bond strength.

Surface profile of different heat-treated nickel-titanium files before and after root canal preparation

The aim of this study was to evaluate surface wear, presence of microcracks and surface irregularities of WaveOne (WO) and WaveOne Gold (WOG) instruments before and after multiple uses. Eight Primary instruments of the WO and WOG systems were evaluated, each one was used to prepare six mesial canals of extracted human mandibular molars. The surface of the instruments was evaluated before use (T0), after instrumentation of three (T1) and six (T2) root canals. Surface wear was analyzed using a three-dimensional optical profiler and the presence of microcracks and surface irregularities were evaluated using a tabletop scanning electron microscopy. The Friedman test was used to assess surface wear and Kruskal-Wallis test to evaluate the presence of microcracks and surface irregularities, with a 5% significance level. There was a significant increase in wear in both groups at T2, compared to T0 (p=0.0003). The surface wear after instrumentation of six canals (T2-T0) was statistically greater in the WOG group, than in the WO group (p=0.02), where the presence of microcracks was significantly greater and increased after multiple uses (p<0.05). The presence of surface irregularities in the cutting blade before and after use was statistically greater in the WOG group than WO group (p<0.05). Wear of the cutting blade, microcracks and surface irregularities were observed on the surface topography of all the instruments after multiple uses. These surface changes may affect the cutting efficiency of WOG files and increase the risk of fracture of WO files.

The medicinal importance of Thyme plant (Thymus vulgaris)

Medicinal and aromatic plants are a group of the oldest plants known and used by man throughout the ages for different fields, as they are used as food and medicine, in the middle and modern ages. The importance of these plants has increased, and their uses varied. The term medicinal plants include different types of plants that have therapeutic activities. These medicinal plants are considered among the sources rich in chemical components that can be used for the treatment of a specific disease or to reduce it if they are used in pure extract or in the form of fresh, dried, or partially extracted vegetable herbs. In addition to its medicinal importance, some plants have great nutritional value. One of the important medicinal plants is the thyme plant which contains many benefits that treat many health conditions. So, this article aimed to explain the most important components of thyme, in addition to its extreme role as a medicinal plant and its multiple uses as food and medicine, as well as its importance in preventing viruses, especially Corona virus.

Do Eco-Friendly Floral Preservative Solutions Prolong Vase Life Better Than Chemical Solutions?

Cut flowers have become an export income in the global floriculture market. They have multiple uses, such as for home beautification, in ceremonies (including weddings and funerals), and as symbols of love, appreciation, respect, etc., in humane society. Each type of cut flower has a different vase life and the longevity of their freshness is linked to preharvest, harvest, and postharvest tools and conditions. The postharvest quality and vase life must be considered in order to obtain the desirable qualities of cut flowers, and factors that affect this are important in the floral industry. The use of floral preservative solutions is good practice for prolonging the vase life of cut flowers. Currently, the eco-friendly solutions, which are used as floral preservatives for extending cut flower vase life, have been discovered to be a low-cost and organic alternative as compared to chemical solutions. However, there are certain problems associated with the use of chemical and eco-friendly solutions. In this review, we summarize several potential approaches to improve flower vase life and discuss the best choices for holding-preservative-solution practices.