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A variety of organic and inorganic pollutants in water environments pose threats to human health. Therefore, it is critical to develop effective techniques to determine and monitor the levels of water contamination. Compared to traditional detection methods, electrochemical sensors have the advantages of high sensitivity, low detection limits, and good selectivity. In this review, we summarize the progress made from 2000 to 2020 regarding the development of electrochemical sensors capable of detecting typical pollutants in different water environments. Since the concentrations of typical organic contaminants (antibiotics and pesticides) in water environments are often very low (generally at the nmol level), further improvements to the electrode sensitivity and detection limit will be necessary. We also found that more detailed cost analysis of electrode materials is needed to support future production and applications. When we apply the electrode to detect real water samples, the anti-interference and electrochemical sensor componentization need to be further enhanced. Besides, although groundwater serves as the main, or only, source of drinking water in many areas, current studies on the electrochemical detection of groundwater pollutants are limited. We hope that this review will provide new ideas for the future development of electrochemical water contaminant sensors.Nephropathy or kidney disease involves the deterioration of kidney functions, causing severe diseases, such as proteinuria, chronic kidney diseases, and kidney failure. Currently, nephropathy that develops into kidney failure is increasing globally, as indicated by the increasing number of patients undergoing hemodialysis. Some developed analytical methods for nephropathy using albumin, creatinine, uric acid, and the urinary albumin-to-creatine ratio biomarkers, including spectrophotometry, turbidimetric immunoassay, and ELISA, have been reported so far, providing good accuracy and precision. However, WHO has established guidelines for developing diagnostic tools that meet several criteria Affordable, Sensitive, Specific, User-friendly, Rapid and Robust, Equipment-free, Delivered to those who need it. This means that nephropathy detection can be carried out using a simple method compatible with point-of-care that allows independent urine analysis by patients. For this purpose, the use of paper-based analytical devices (PADs) as an alternative platform for the detection of albumin, creatinine, uric acid, and the urinary albumin-to-creatine ratio were reviewed.Potentiometric sensors based on ion-selective membrane electrodes have continued to get great attention from the scientific community. These sensors have been employed in several applications including medicine, forensic analysis, environmental assessment, industry, agriculture, and pharmaceutical drug analysis. Indeed, these sensors possess several advantages, for example, simple design, fabrication, and manipulation, rapid response time, good selectivity, applicability to colored and turbid solutions, and possible interfacing with automated and computerized systems. On the other hand, therapeutic drug monitoring and the detection of pharmaceutical drugs in their pharmaceutical formulations and biological matrices are highly significant from a medical point of view, especially for drugs with a narrow therapeutic index, such as anticancer drugs, which can cause fatal side effects for patients. Interestingly, potentiometric sensors have been broadly employed as one of the most important electrochemical approaches for pharmaceutical drug analysis. Moreover, the breakthroughs in potentiometric sensors based on ion-selective electrodes (ISEs) make them superior to the other reported methods for pharmaceutical drug analysis in terms of many performance parameters, such as sensitivity, selectivity, low detection limit, and low cost. In this review, we try to offer a summary prologue to the applicability and merits of potentiometric sensors that have been employed for pharmaceutical drug analysis while emphasizing their application for the assay of pharmaceutical drugs in their dosage forms and the in-vivo assay of pharmaceutical drugs in different biological samples such as milk, water, plasma, and urine.Hormones are essential chemical messengers that modulate body homeostasis and regulate appetite, mood, reproduction, and metabolism in the human body. Its dysregulation in the body can cause diabetes, Alzheimer’s disease, and autism. The detection of hormone levels in biological fluids, including serum samples, could facilitate the precaution, diagnosis, and cure of diseases. Voltammetric sensing devices exhibiting significant sensitivity, selectivity, as well as facile, cost-effective fabrication, are one of the promising methods for detecting hormone levels. Thus, this review briefly highlights recent advances toward developing voltammetric sensors for a wide spectrum of amino acid-derived, peptide, and lipid-derived hormones alongside their applications to the analyses of human serum samples. Furthermore, several challenging issues and the prospects of voltammetric hormone-sensing devices in clinical diagnostic applications are discussed.Gold nanoparticles (AuNPs) have been used as colorimetric biosensors by utilizing the difference in color between the dispersed (red) and aggregated (blue) states. We previously developed a biosensor that converts sandwich-type thrombin recognition to RNA amplification and color difference of AuNPs. But the sensitivity was insufficient because of the linear signal amplification mechanism. In this study, we designed an exponential signal amplification biosensor based on transcription-reverse transcription concerted (TRC) reaction.Sharks are top predators and play an important role in the regulation of marine ecosystems at lower trophic position. Mustelus californicus, Sphyrna zygaena, and Isurus oxyrinchus prove to be important fishery resources along the western coast of Baja California Sur and cohabit the same coastal areas, probably sharing resources. However, our knowledge about ecological dynamics of multiple species coexisting and sharing similar habitat resources is still limited, particularly for predators such as sharks. Therefore, this study focuses on the analysis of trophic ecology of the sharks species, using carbon (13C) and nitrogen (15N) stable isotope values in muscle tissues coupled with trace element concentration (Hg, Se, and Cd) in muscle and hepatic tissues of sharks. The values of δ13C (M. californicus -17.3 ± 1.1‰, S. zygaena -17.9 ± 0.5‰, and I. oxyrinchus -18.3 ± 0.3‰) and δ15N (M. californicus 18.2 ± 1.1‰, S. zygaena 18.4 ± 0.9‰, and I. oxyrinchus 17.8 ± 1.1‰) indicated that these species feed in the Gulf of Ulloa all throughout the year, and for extended periods with similar habitat use and trophic niche. The above-mentioned statement is also a conclusion supported by the significant correlation between isotopic and trace element concentrations in the muscular tissues in all studied species. Thus, the results of the present study emphasize the habitat and niche characteristics of three sympatric sharks off the coast of Baja California Sur, Mexico.Distinguishing the significance of business environments for technical small and medium-sized enterprises (SMEs), this study examines the connection between business environments, GDP growth, and SMEs’ financing choices in Vietnam. The study considered the agency theory as a theoretical base to explain how information asymmetry between SMEs and lenders influences SMEs’ financing choices and encompasses the effects on business environment and GDP growth of Vietnam. For this binary logistic regression, text is applied. Global Entrepreneurship Monitor and World Bank data were analyzed. The findings of the study are robust and showed that SME financing (e.g., formal and informal) under the financial infrastructure and tax regulation may enhance formal credit choice and reduce informal credit choice. This enhances the depth in the business environment of technical SMEs and found significant effects on GDP growth. For the first time, this research examines the impact of information asymmetry and agency theory on restaurant financing choices. The research has significance for industry practitioners and governments interested in SMEs’ financial viability. On the recent topicality, study also presents policy implications for key stakeholders.Since markets are undergoing severe turbulent economic periods, this study investigates the information transmission of energy stock markets of five regions including North America, South America, Europe, Asia, and Pacific where we differentiated the regional energy markets based on their developing and developed state of economy. We employed time-frequency domain from Jan 1995 to May 2021 and found that energy stocks of developed regions are highly connected. The energy markets of North America, South America, and Europe are the net transmitters of spillovers, whereas the Asian and Pacific energy markets are the net receivers of spillovers. The results also reveal that the connectedness of regional energy markets is time and frequency dependent. Regional energy stocks were highly connected following the Asian financial crisis (AFC), global financial crisis (GFC), European debt crisis (EDC), shale oil revolution (SOR), and COVID-19 pandemic. Time-dependent results reveal that high spillovers formed during stress periods and frequency domain show the higher connectedness of regional energy stock markets in the short run followed by an extreme economic condition. These results have significant implications for policymakers, regulators, investors, and regional controlling bodies to adopt effective strategies during short run to avoid economic downturns and information distortions.The world faces tremendous challenges and environmental crises due to the rising strength of wastewater. The conventional technologies fail to achieve the quality water that can be reused after treatment means “zero effluent” discharge of the industrial effluent. Therefore, now the key challenge is to develop improved technologies which will have no contribution to secondary pollution and at the same time more efficient for the socio-economic growth of the environment. Sustainable technologies are needed for wastewater treatment, reducing footprint by recycling, reusing, and recovering resources. Advanced oxidation process (AOP) is one of the sustainable emerging technologies for treating refractory organic contaminants present in different industrial wastewaters like textile, paper and pulp, pharmaceuticals, petrochemicals, and refineries. This critical review emerges details of advanced oxidation processes (AOPs), mentioning all possible permutations and combinations of components like ozone, UV, the catalyst used in the process. Non-conventional AOP systems, microwave, ultrasound, and plasma pulse assisted are the future of the oxidation process. This review aims to enlighten the role of AOPs for the mineralization of refractory organic contaminants (ROC) to readily biodegradable organics that cannot be either possible by conventional treatment. The integrated AOPs can improve the biodegradability of recalcitrant organic compounds and reduce the toxicity of wastewater, making them suitable for further biological treatment.