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The carbon oxides (CO2 and CO) in the insulating oil of power transformers come from the thermal aging of cellulosic insulating paper; the CO2/CO ratio can reflect the aging state of cellulosic insulating paper. At present, the formation mechanisms of CO2 and CO in oil-immersed power transformers are still unclear. In this article, the ReaxFF reaction force field is used to simulate the thermal aging process of cellulosic insulating paper, and the main reaction pathways of CO2 and CO molecules formed by cellulose pyrolysis are obtained. The study finds that the amount of CO2 and CO generated is related to temperature. When the pyrolysis temperature continues to rise, the amount of CO2 generated shows a downward trend, while the amount of CO generated continues to increase, and the CO2/CO ratio continues to decrease. The simulation results are consistent with the previous experimental results. Through pathway tracking, it is found that the CO2 and CO molecules are mainly derived from certain specific atoms of cellulose molecules. The COSMO-RS module is used to analyze the change trend of the solubility of CO2 and CO in insulating oil with temperature. The results show that the solubility of CO2 and CO decreases with the increase of insulating oil temperature, which provides theoretical support for accurate application of carbon oxides aging evaluation index at different temperatures. [ABSTRACT FROM AUTHOR]

In this work, different alternatives to conventional tertiary treatment of pulp and paper (P&P) wastewater (WW), i.e., physicochemical coagulation-flocculation, were investigated to enhance the environmental and economic sustainability of industrial wastewater treatment. In particular, following a preliminary characterization of secondary effluents, cloth filtration and adsorption were studied, the former by pilot-scale tests, while the latter at laboratory scale. An economic analysis was finally accomplished to verify the full-scale applicability of the most promising technologies. Cloth filtration showed excellent total suspended solids (TSS) removal efficiency (mean 81% removal) but a very limited influence on chemical oxygen demand (COD) (mean 10% removal) due to the prevalence of soluble COD on particulate COD. Adsorption, instead, led to a good COD removal efficiency (50% abatement at powdered activated carbon—PAC—dosage of 400 mg/L). The economic analysis proved that adsorption would be convenient only if a local low-cost (100 €/ton) adsorbent supply chain was established. Ultrafiltration was considered as well as a potential alternative: its huge capital cost (19 M€) could be recovered in a relatively short timeframe (pay-back time of 4.7 years) if the ultrafiltrated effluent could be sold to local industries. [ABSTRACT FROM AUTHOR]

Creatinine is a biochemical waste that is disseminated continually inside human blood. A synthetic polymer is developed in this study using Molecularly Imprinted Polymerization (MIP) technology with the precipitation polymerization method. The MIP polymer is used for finding the levels of creatinine from human serum samples with different creatinine concentrations. The MIP polymer is very selective to the specific adsorption of the molecules of creatinine. The produced MIP polymer is suitable for evaluating creatinine concentrations until 50 parts per million (ppm) that is thrice greater than the standard. The fabrication of chip-sized Micro-Electro-Mechanical-Systems (MEMS)-based interdigital (ID) sensors is described. The operation of the MEMS sensor is verified using the technique of Electrochemical Impedance Spectroscopy (EIS). The presented details of the development of MEMS ID sensor and creatinine specific MIP polymer are for detecting raised biotoxic waste levels, i.e. creatinine management is part of our research. The raised levels need monitoring by frequent pathological visits to those patients who have impaired kidney functioning. The complete system will be helpful for creatinine management at any time from home at a low cost. While early detection of an increase in creatinine and monitoring of kidney health to prevent further health-related complications are the goal of this research, results of up to 50 ppm are accessed. Until 50 ppm of MIP functionality is checked for confirming the MIP polymer adsorption of creatinine and the results are shown, which helps establish the sensing technology even if used for a patient with a high creatinine level. [ABSTRACT FROM AUTHOR]

Titanium tetrachloride (TiCl4) is a well-known source of titanium (Ti) for the formation of titanium nitride (TiN) barrier material in the semiconductor interconnection process; however, the reaction of by-products with airborne molecules can cause unexpected pump trips and equipment breakdown from the by-product powder build-up. Plasma scrubbers are used to decompose by-products, but hydrogen chloride (HCl) and nitrogen oxides are produced during and after the process. The process mechanisms change when the temperature and applied power of the heat source change. In this paper, we study the influence of the reactor temperature and applied power to the heat source on the decomposition capacity of TiCl4 in a plasma pretreatment system (PPS). We examine the effect of the temperature and heat source power to understand the reaction mechanisms for the composition and decomposition of gaseous species with chemical reactions through simultaneous methods. We analyzed the system with computational fluid dynamics (CFD) and chemical kinetic simulation to investigate the changes of the system mechanism. Subsequently, we achieved results for the correlation between the temperature of the reactor, power applied to the heat source, composition and decomposition of species, and chemical reaction mechanisms. [ABSTRACT FROM AUTHOR]

Copyright of Traditional Chinese Drug Research & Clinical Pharmacology is the property of Traditional Chinese Drug Research & Clinical Pharmacology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Mechanochemistry and oleochemistry and their combination have been known for centuries. Nevertheless, bioeconomy and circular economy concepts is much more recent and has motivated a regain of interest of dedicated research to improve alternative technologies for the valorization of biomass feedstocks. Accordingly, this review paper aims essentially at outlining recent breakthroughs obtained in the field of mechanochemistry and oleochemicals such as triglycerides, fatty acids, and glycerol derivatives. The review discusses advances obtained in the production of small chemicals derived from oils with a brief overview of vegetable oils, mechanochemistry and the use of mechanochemistry for the synthesis of biodiesel, lipidyl-cyclodextrine, dimeric and labelled fatty acids, calcium diglyceroxide, acylglycerols, benzoxazine and solketal. The paper also briefly overviews advances and limits for an industrial application. [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFAS) are a large class of synthetic compounds, many of which are persistent, mobile and toxic (PMT). The sheer number of PFAS makes a substance-by-substance based approach to regulating this group unfeasible. Given the known risks of many PFAS, a precautionary approach (i.e., the Essential Use Concept; EUC) has been called for, whereby any substance is assumed to be harmful and should be phased out, unless it is shown that: (a) the use of this substance is necessary for health and safety, or is critical for the functioning of society and (b) there are no available technically and economically feasible alternatives. While experts, including chemists and toxicologists, are well-placed to assess the second criteria, determining what is necessary for the "functioning of society" requires a wider consideration of societal beliefs and preferences and greater involvement of various interested and affected parties, especially those whose voices are less heard but may be most vulnerable. The aim of the current paper is to provide a preliminary framework and research agenda outlining why and at what points in the essential use decision-making process broader societal perspectives are required, and how such 'social data' can be collected. The ultimate goal is to improve chemicals management by supporting citizens in becoming more informed and engaged participants in relevant debates and policies, including in how to operationalise the EUC. [ABSTRACT FROM AUTHOR]

The formation of hydrogen sulfide (H2S) in petroleum reservoirs by anaerobic microbial activity (through sulfate-reducing microorganisms, SRMs) is called biogenic souring of reservoirs and poses a risk in the petroleum industry as the compound is extremely toxic, flammable, and corrosive, causing devastating damage to reservoirs and associated surface facilities. In this paper, we present a workflow and the tools to assess biogenic souring from a pragmatic engineering perspective. The retention of H2S in the reservoir due to the reactions with iron-bearing rock minerals (e.g., siderite) is shown in a theoretical approach here and supported with literature data. Cases are provided for two fields under secondary (waterflooding) and tertiary flooding with microbial enhanced oil recovery (MEOR). The use of the Monte Carlo method as a numerical modeling tool to incorporate uncertainties in the measured physical/chemical/biochemical data is demonstrated as well. A list of studies conducted with different chemicals alone or in combination with various biocides to mitigate biogenic souring provides an overview of potential inhibitors as well as possible applications. Furthermore, the results of static and dynamic inhibition tests using molybdate are presented in more detail due to its promising mitigation ability. Finally, a three-step workflow for the risk assessment of biogenic souring and its possible mitigation is presented and discussed. [ABSTRACT FROM AUTHOR]

Copyright of Contributions to Tobacco & Nicotine Research is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper describes a straightforward modeling procedure to derive 'expected risk' (ER) of chemical substances. Starting from proposed use volumes, intended uses, physical and chemical substance properties and toxicity information, the procedure combines multimedia environmental fate modeling with species sensitivity modeling to derive the probability that exposure concentrations exceed critical effect concentrations. The procedure was tested on 1977 so-called mono-constituent organic chemicals that had been registered to be marketed in the EU, after 'possibility to be used safely' had been demonstrated by showing that the possible Risk Quotients (RQ) defined as PEC/PNEC ratios (Predicted Exposure Concentration & Predicted No Effect Concentration) were expected to remain below the value of 1, as required by REACH. It appears from this study that (i) RQ and ER of chemicals can be calculated readily, reliably, transparently and reproducibly, that (ii) both RQ and ER can be used to assess whether a new chemical may exceed a chosen acceptability level, but that (iii) in addition ER can be straightforwardly used to rank chemicals according to expected environmental safety. In conclusion, the paper states that modeling ER of chemicals (instead of estimating RQ values), could strengthen the scientific basis of environmental risk assessment for use in REACH. The paper further recommends that more robust environmental risk calculation can be done by using acute EC50, instead of chronic NOEC as critical effect concentration. [ABSTRACT FROM AUTHOR]

The process of development is intricate and couple-dependent phenomenon. Accordingly, the study of molecular and cellular biology-based developmental toxicology biomarkers increasingly is becoming an important part of risk assessment and management of chemicals for detection of health outcomes and/or biological endpoint like cytotoxicity, cell death, etc. Since, the evolution of developmental toxicology field a number of tools/markers have been developed or addressed to deal with developmental outcomes, which can ultimately be used for the development of adverse outcome pathways (AOPs) of developmental toxicants. As a result, this paper provides an overview of the current state of developmental toxicology biomarkers and describes the strategies used in the selection and evaluation of such biomarkers in the context of developmental toxicity studies. Here, we discuss about the biological markers that are directly linked to developmental toxicity with respect to future revolutionary perspectives. Additionally, this chapter will address different associated outcomes of developmental exposure by intriguing advance techniques. The discussion focuses on the challenges associated with the development of biomarkers for developmental toxicity and highlights some of the recent advances in this area. Finally, the chapter concludes with a brief discussion of the future prospects for the use of molecular and cellular biology-based developmental toxicity biomarkers. Hope the present state of the art will provide a succinct summary of recent developments of biomarkers of developmental toxicology. [ABSTRACT FROM AUTHOR]

For most Indian families, rice (Oryza sativa L.) is a nutritious staple. It is also considered India's and the World's primary food source. Cultivation of rice in India is confronted with variegated agro-climatic conditions, various soil types, and multiple biotic and abiotic factors. Among the various biotic constraints, blast disease caused by fungi Magnaporthe oryzae (anamorph Pyricularia oryzae) is shown to be responsible for significant yield losses every year. In India, blast epidemic occurs due to various races of the pathogen, resulting in resistance breakdown within a very short period, causing severe damage. The pathogen is an ascomycetes fungi which infect rice seedlings up to the adult stage of the crop. The control can be achieved through several approaches, including cultural, nutritional, chemical, and biocontrol methods. This review paper aims to provide a precise view of the various methods that can be used to control blast diseases caused by M. oryzae (anamorph P. oryzae). [ABSTRACT FROM AUTHOR]

The objective of this study is to enhance the longevity of damaged or defective components through necessary repairs. In corrosive environments, stainless steels, such as 304 and 316NG austenitic stainless steel (SS), are preferred due to their chemical composition. Notably, 316SS contains a higher molybdenum content, resulting in improved resistance to pitting and crevice corrosion. The simulation of intergranular stress corrosion cracking (IGSCC) in SS piping relies on factors like applied and residual stresses, environmental conditions, and sensitization degree. To understand crack growth rates and times-to-initiation for each material, "damage parameters (DPs)" are utilized. These DPs consolidate the individual influences of various parameters. To estimate the DPs an artificial neuronal network (ANN) is proposed in this work. The ANN serves as a tool for predicting the DPs based on the given inputs. The obtained results are then utilized in numerical simulations to assess crack growth rates, times-to-initiation, and reliability for damaged 304SS and 316SS. Finally, this paper investigates the impact of replacing old 304 material with new 316NG material on piping reliability. By examining the effects of this replacement, the study aims to provide insights into how the reliability of the piping can be improved through material upgrades. [ABSTRACT FROM AUTHOR]

Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Over the past decades, Chemical-induced Disease (CID) relations have attracted extensive attention in biomedical community, reflecting wide applications in biomedical research and healthcare field. However, prior efforts fail to make full use of the interaction between local and global contexts in biomedical document, and the derived performance needs to be improved accordingly. In this paper, we propose a novel framework for document-level CID relation extraction. More specifically, a stacked Hypergraph Aggregation Neural Network (HANN) layers are introduced to model the complicated interaction between local and global contexts, based on which better contextualized representations are obtained for CID relation extraction. In addition, the CID Relation Heterogeneous Graph is constructed to capture the information with different granularities and improve further the performance of CID relation classification. Experiments on a real-world dataset demonstrate the effectiveness of the proposed framework. [ABSTRACT FROM AUTHOR]

Copyright of Knowledge: International Journal is the property of Institute for Knowledge Management and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In recent years, food safety caused by foodborne pathogens and spoilage bacteria has become a major public health problem worldwide. Bacteriocins are a kind of antibacterial peptide synthesized by microbial ribosomes, and are widely used as food preservatives. However, when used individually bacteriocins may have limitations such as high cost of isolation and purification, narrow inhibitory spectrum, easy degradation by enzymes, and vulnerability to complex food environments. Numerous studies have demonstrated that co-treatment with bacteriocins and a variety of chemical substances can have synergistic antibacterial effects on spoilage microorganisms and foodborne pathogens, effectively prolonging the shelf life of food and ensuring food safety. Therefore, this paper systematically summarizes the synergistic bacteriostatic strategies of bacteriocins in combination with chemical substances such as essential oils, plant extracts, and organic acids. The impacts of bacteriocins when used individually and in combination with other chemical substances on different food substrates are clarified, and bacteriocin–chemical substance compositions that enhance antibacterial effectiveness and reduce the potential negative effects of chemical preservatives are highlighted and discussed. Combined treatments involving bacteriocins and different kinds of chemical substances are expected to be a promising new antibacterial method and to become widely used in both the food industry and biological medicine. [ABSTRACT FROM AUTHOR]

The aim of the BrineRIS project is to explore brines in RIS countries potential for critical metal extraction In the frame of this project the concentration of mineral brines in three geothermal wells located in the Beiuş Basin (northwestern Romania) was determined by analyzing the water from the wells. Until recently no reliable trace element data were available from Beiuş basin. Following the new analyses, the geothermal water extracted by TRANSGEX SA company from wells F-3001H, F-3003H, and F-3005H revealed exceptionally low concentrations of associated chemical compounds. The Liconcentration is only ~ 22 -- 32 µg/l. Zn, I, Rb and As present in similar concentrations, while other trace elements (e.g. Co, V, Ti) are below detection limit. The Sr (~ 540 -- 680 µg/l), Ba (~ 170 -- 200 µg/l) and B (~ 70 -- 100 µg/l) concentrations are slightly elevated, but still low. Therefore, the water in this "geothermal reservoir" can be classified as relatively potable, but it is not appropriate for critical metal extraction. In this paper, some documented concentrations from previous years have been compared to recent concentrations. In addition, the relationship between geology and water chemistry is emphasized in order to determine the reason for the absence of solutes that were expected to be found in this water. [ABSTRACT FROM AUTHOR]

Featured Application: The L-FDM technique enables the direct introduction of chemicals, dyes, radioactive substances, pesticides, antibiotics, nanoparticles, trace elements, fertilizers, phosphors, monomers for polymerization, proteins, peptides, and active ingredients in the direct printing process from a polymer material with a typical FDM printer. With the proposed technology, it is now possible to introduce chemical substances into polymer filaments that were previously impossible to apply due to undergoing physical or chemical transformations during previous processing processes. This article discusses methods that eliminate the need for costly and energy-consuming processing equipment. These methods can be utilized in any laboratory by users without access to specialized devices. A novel L-FDM technique that builds upon the fundamentals of the FDM additive manufacturing process has been developed. It includes a mechanism that directly incorporates a chemical substance and alters polymer fibers throughout the fine process. This method eliminates the need for additional extrusion operations and compounding equipment to introduce chemical additives and solvents. This advancement opens up new opportunities for printers to be used in chemical labs to test new or known chemical substances. The paper outlines the technological assumptions, potential applications, and practical examples of direct filament modification using the L-FDM technique. The modifications made to the mechanical properties of the printed objects were confirmed through thermal analysis techniques (DSC), water contact angle measurements, electron microscopy (SEM-EDS), and mechanical analysis. [ABSTRACT FROM AUTHOR]

A growing body of evidence suggests that chemicals interfere with the age of onset of menarche. We conducted a review in order to demonstrate the relationship between several categories of chemicals and menarche. We searched for English language papers using the Medline/PubMed database until April 2023. The chemical factors found to affect menarche were prenatal and antenatal smoke, phthalates, phenols, organochlorines, perfluoroalkyls and polyfluoroalkyls, metals, air pollutants and polybrominated diphenyl ethers. Low or high exposure to each chemical compound could affect the age of menarche, leading to early or delayed menarche. Furthermore, the results show that intrauterine exposure may have a different impact from antenatal exposure. There is evidence that endocrine-disrupting chemicals affect the age of menarche, but more research needs to be conducted. [ABSTRACT FROM AUTHOR]

Existing structures may suffer from resistance deterioration due to repeated attacks. The modeling of resistance deterioration is a critical ingredient in the reliability assessment and service life prediction of these degraded structures. In this paper, an explicit compound Poisson process-based model is developed to describe the shock deterioration of structural resistance, where the magnitude of each shock deterioration increment is modeled by a Gamma-distributed random variable. The moments (mean value and variance) and the distribution function of the cumulative shock deterioration are derived in a closed form, based on a proposed W-function. A method for the efficient calculation of the W-function is presented, which reduces to the Bessel type I function if the shock deterioration increment is exponentially distributed (a special case of Gamma distribution). The proposed shock deterioration model is applicable to either a stationary or a nonstationary Poisson process of random jumps. Subsequently, the overall resistance deterioration is modeled as the linear combination of gradual and shock deteriorations, based on which the proposed model can be used in the time-dependent reliability assessment of aging structures efficiently. A numerical example is presented to demonstrate the applicability of the proposed deterioration model by estimating the time-dependent reliability of an aging bridge. It is found that a smaller threshold for the degraded resistance leads to greater mean value and standard deviation of the time to failure, and this effect is enhanced by a smaller occurrence rate of the shock deterioration. [ABSTRACT FROM AUTHOR]

Quantitative structure-activity relationship (QSAR) is important for safe, rapid and effective risk assessment of chemicals. In this study, two QSAR models were established with 1230 chemicals to predict toxicity towards Tetrahymena pyriformis using multiple linear regression (MLR) method. The topological(T)-QSAR model was developed by using topological-norm descriptors generated from the topological structure, and the spatial(S)-QSAR model were built with spatial-norm descriptors obtained from the three-dimensional structure of molecules and topological-norm descriptors. The r2training and r2test are 0.8304 and 0.8338 for the T-QSAR model, and 0.8485 and 0.8585 for the S-QSAR model, which means that T-QSAR model and S-QSAR model can be used to predict toxicity quickly and accurately. In addition, we also conducted validation on the developed models. Satisfying validation results and statistical parameters demonstrated that QSAR models based on the topological-norm descriptors and spatial-norm descriptors proposed in this paper could be further utilized to estimate the toxicity of chemicals towards Tetrahymena pyriformis. [ABSTRACT FROM AUTHOR]

The manufacture and production of industrial chemicals continues to increase, with hundreds of thousands of chemicals and chemical mixtures used worldwide, leading to widespread population exposures and resultant health impacts. Low-wealth communities and communities of color often bear disproportionate burdens of exposure and impact; all compounded by regulatory delays to the detriment of public health. Multiple authoritative bodies and scientific consensus groups have called for actions to prevent harmful exposures via improved policy approaches. We worked across multiple disciplines to develop consensus recommendations for health-protective, scientific approaches to reduce harmful chemical exposures, which can be applied to current US policies governing industrial chemicals and environmental pollutants. This consensus identifies five principles and scientific recommendations for improving how agencies like the US Environmental Protection Agency (EPA) approach and conduct hazard and risk assessment and risk management analyses: (1) the financial burden of data generation for any given chemical on (or to be introduced to) the market should be on the chemical producers that benefit from their production and use; (2) lack of data does not equate to lack of hazard, exposure, or risk; (3) populations at greater risk, including those that are more susceptible or more highly exposed, must be better identified and protected to account for their real-world risks; (4) hazard and risk assessments should not assume existence of a "safe" or "no-risk" level of chemical exposure in the diverse general population; and (5) hazard and risk assessments must evaluate and account for financial conflicts of interest in the body of evidence. While many of these recommendations focus specifically on the EPA, they are general principles for environmental health that could be adopted by any agency or entity engaged in exposure, hazard, and risk assessment. We also detail recommendations for four priority areas in companion papers (exposure assessment methods, human variability assessment, methods for quantifying non-cancer health outcomes, and a framework for defining chemical classes). These recommendations constitute key steps for improved evidence-based environmental health decision-making and public health protection. [ABSTRACT FROM AUTHOR]

Modern industrial development is accompanied by the increasingly frequent occurrence of accidental release atmospheric dispersion events, causing extremely serious human and property losses and environmental pollution, in which rapid and accurate prediction of atmospheric dispersion is an important task to mitigate the unexpected consequences. In this paper, we take the case of previous years as the starting point, firstly, the occurred hazardous chemical atmospheric dispersion accidents in the past five years are shown, and the related concepts of hazardous chemical atmospheric dispersion are given. Then, the current state of atmospheric dispersion research is reviewed, well-known experiments on atmospheric dispersion of hazardous chemicals are summarized, and correspondingly the existing atmospheric dispersion prediction models are classified into simplified-experience models, mechanism- and rule-driven models and data-driven models. In particular, for the purpose of rapid atmospheric dispersion prediction, some research on atmospheric detection and identification are analyzed in detail. Moreover, the relevant professional software for atmospheric dispersion prediction are introduced, and also their calculation adaptabilities regarding time-consumption and output accuracy are discussed. Thereinafter, according to the shortcomings of existing atmospheric dispersion prediction models in research and application fields, the development trend of atmospheric dispersion prediction research and technology is foreseen, and some feasible future research directions are proposed as follows: (1) the fusion of image processing techniques, the establishment of a database of historical accident scene information and meteorological information, (2) new correction algorithms, and (3) an emergency response system for full-scene atmospheric dispersion prediction. [ABSTRACT FROM AUTHOR]

Food safety is a global concern in today's world, and harnessing food safety in Sub-Saharan Africa, especially Nigeria and Ghana are momentous. This review presents an insight into the situation of food safety in Nigeria and Ghana. Using a desktop review technique, research papers were evaluated to find major sources of food safety concerns. It was revealed that many studies reported on food contamination at the consumption level whereas few reported on the healthiness of the production chain. Improper handling of food at the local markets, vending sites hygiene practices of food vendors, and bad transportation and packing systems have all been implicated. Inadequate education is a major cause of food contamination, especially at the consumption level. Again, etiologic agents responsible for food-borne illness in Ghana and Nigeria range from viruses, fungi, parasites, and protozoans to bacteria. They include rotavirus, hepatitis A virus, Lassa fever (LHF), human noroviruses (HNoV), Aspergillus parasiticus, Aspergillus flavus, Aspergillus niger, Taenia solium, Ascaris spp., Toxoplasma gondii, Cryptosporidium spp. Enterobacter spp., Pseudomonas spp., Campylobacter spp., Escherichia coli. Staphylococcus spp., Salmonella spp., Vibrio cholerae and Listeria monocytogenes. Their toxins are responsible for numerous food contaminants. Some foods are contaminated with chemicals including pesticide residues, lead, mercury, etc. Laws of food safety are not well enforced leading to complications in the food production chain. Rigorous monitoring and evaluation coupled with surveillance and education to harness the situation and detect issues that compromise the right process is a necessity. Finally, intentional enforcement of regulations by regulatory agencies will go a long way to curb food contamination and food-borne illnesses within the region. [ABSTRACT FROM AUTHOR]

The major portion of the marine area is polluted with waste of marine organism that creates severe environmental problems. This includes oyster, snail, mollusca, prawn, crab, shrimp, lobster, crab shell, mussels to name a few. This waste material, is a rich source of nutrients and chemicals, such as proteins, amino acids, minerals, enzymes, chitin, carotenoids, calcium, calcium carbonate. Unfortunately, these resources are underutilized and they are discarded into the environment. However, there are many ways to treat these marine resources to extract valuable chemicals and food, as well as pharmaceutical, nutraceuticals and biomedical agents. This paper is focused on the extraction and usage of value-added products originating from marine resources. [ABSTRACT FROM AUTHOR]

The paper shows the method of making the equations of the mathematical model that describes the dependence of several mechanical and casting properties on the chemical composition of the cast irons of the second fusion and on the casting conditions. The chemical composition taken into account refers to the contents of C, Si and Mn and the casting conditions analysed were: casting temperature, superheating time and superheating temperature. After performing the specific mathematical calculations, the specific mathematical equations were obtained that describe the dependence of the studied properties according to the parameters of the casting process taken into account. [ABSTRACT FROM AUTHOR]

This paper provides updated odour detection threshold values (ODTV) for fifty-two (52) pure compounds. In 2014, the first updated odour threshold data (Bokowa, 2014) was presented for twenty-four (24) pure compounds. Over the past eight (8) years, more studies were performed, and another twenty-eight (28) compounds were chosen for odour threshold studies. There have only been a few publications with odour detection threshold values for pure chemicals, and most of these publications have not been updated and are therefore not current. Between 1960 and 1990, different methodologies for determining odour thresholds were used. In the 1960 and the 1970s, the common approach for defining ODTV was to determine the odour threshold value by smelling a syringe filled with different chemical concentrations. This, of course, was highly inaccurate and did not rely on scientific analysis, but rather on estimation. In the late 1970s when dynamic olfactometry was introduced, new ODTVs were developed based on the dynamic olfactometry method. However, at this time, it was unknown that the flows from the sniffing ports play an important role in the evaluation process, and, therefore, in the final results. In the late 1980s, flows at the sniffing ports of the olfactometer were too low, and actual samples were diluted with ambient air during evaluations resulting in much higher odour detection threshold values (actual lower results). In 2003 with a newly developed European Standard, and armed with the knowledge that sniffing flows during evaluations should be around 20 L/min in order not to dilute the sample during analysis, there was a need to update the ODTV. This study is based on the evaluation of fifty-two compounds for odour detection threshold values. These values were compared with those previously developed for those chemicals or any other available resources. Odour offensiveness and complaint threshold values are also determined for these compounds. [ABSTRACT FROM AUTHOR]

Currently, DNA strand displacement is often used to build neural networks or solve logical problems. While there are few studies on the use of DNA strand displacement to solve the higher order equations. In this paper, the catalysis, degradation, annihilation and adjusted reaction modules are built through DNA strand displacement. The chemical reaction networks of the corresponding higher order equations and simultaneous equations are established through these modules, and these chemical reaction networks can be used to build analog circuits to solve binary primary simultaneous equations and binary quadratic simultaneous equations. Finally, through Visual DSD software verification, this design can realize the solution of binary primary simultaneous equations and binary quadratic simultaneous equations, which provides a reference for DNA computation in the future. [ABSTRACT FROM AUTHOR]

The components with molecular communication (MC) functionalities can bring an opportunity for emerging applications in fields from personal healthcare to modern industry. In this paper, we propose the designs of the microfluidic transmitter and receiver with quadruple concentration shift keying (QCSK) modulation and demodulation functionalities. To do so, we first present an AND gate design, and then apply it to the QCSK transmitter and receiver design. The QCSK transmitter is capable of modulating two input signals to four different concentration levels, and the QCSK receiver can demodulate a received signal to two outputs. More importantly, we also establish a mathematical framework to theoretically characterize our proposed microfluidic circuits. Based on this, we first derive the output concentration distribution of our proposed AND gate design, and provide the insight into the selection of design parameters to ensure an exhibition of desired behavior. We further derive the output concentration distributions of the QCSK transmitter and receiver. Simulation results obtained in COMSOL Multiphysics not only show the desired behavior of all the proposed microfluidic circuits, but also demonstrate the accuracy of the proposed mathematical framework. [ABSTRACT FROM AUTHOR]

This paper examines whether laws requiring oil and gas firms to disclose the chemicals used in their fracking operations affect the mortgage lending activity for properties located in nearby areas. I hypothesize and find that the disclosure mandate reduces uncertainty about the value of housing collateral and subsequently increases (1) the probability of obtaining a mortgage by 2.5 percentage points (pp), and (2) loan-to-value by 2.2 pp. My main analyses exploit the variation in the location of properties relative to fracking wells. Cross-sectional tests that exploit heterogeneity in drinking water sources and the content of firm disclosures further substantiate my inferences and mitigate endogeneity concerns. These findings suggest that disclosure regulation for oil and gas firms affects housing collateral values, thereby impacting the mortgage market. JEL Classifications: G14; G21; G32; G38; K22; L71; M41; M48. [ABSTRACT FROM AUTHOR]

The nitrogen-rich pyrolysis is a significant technique to improve the utilization and value addition of biomass. The bio-oil derived from the biomass nitrogen-rich pyrolysis is abundant in high-value nitrogenous compounds. Carbamide-pretreated pine powder was used to produce bio-oil through fast pyrolysis in this paper. Effects of pyrolysis temperature and the concentration of carbamide solution on the product distribution and the content of important compounds (e.g., phenols, amines, indoles, pyrroles) in pine powder–derived bio-oil were investigated. The results showed that the bio-char yield decreased as the concentration of carbamide solution increased. The highest bio-oil yield (51.8%) appeared at a temperature of 400 °C and an impregnated carbamide solution concentration of 10%. The contents of acids, ketones, and aldehydes in the bio-oil obtained by carbamide-impregnated pine powder significantly decreased while the content of phenols observably increased. Compared with the bio-oil derived from raw pine powder, there were various nitrogenous compounds generated in the bio-oil produced by carbamide-impregnated pine powder. As the concentration of carbamide solution increased, the varieties of nitrogenous compounds increased. [ABSTRACT FROM AUTHOR]

This study was quasi-experimental research, and the objectives were to i) study behavior in practice for self-prevention in chemicals use before and after using environmental education processes, ii) compare cholinesterase enzyme in blood of sugarcane farmers before and after using environmental education processes, and iii) compare amount of chemical residues in soil in the sugarcane planting areas before and after using environmental education processes. The sample were the 36 sugarcane farmers whom had cholinesterase enzyme in blood equal to or more than risk level, and were selected by multi-stage sampling. Of these test kit used for the analysis of cholinesterase enzyme in blood with the reactive paper of the Department of Health (1997) and chemical residues in soil based on the standard of the Department of Health (1997) by the method of High-Performance Liquid Chromatography (HPLC) with the unit of mg/kg and reported according to the central laboratory. The comparisons of the behavior in practice for self-prevention in chemicals use revealed that after using environmental education processes, mean higher than before with a statistical significance level of 0.01. The comparisons of cholinesterase enzyme in blood of sugarcane farmers revealed that before trials, the most of them had a cholinesterase enzyme level at risk equal to 27 persons or 75.00 %, but after trials they were at a risk equal to 18 persons or 50.00 % which it was lower than before. The sample soil for the analysis of chemicals residues revealed that before trials found the organophosphate 72.15 mg/kg, carbamate 10.00 mg/kg, glyphosate 9.99 mg/kg, and paraquat 5.21 mg/kg which it was at an unsafe level, but after trials found that the organophosphate, carbamate, glyphosate, and paraquat, were at a safe level or not detected. [ABSTRACT FROM AUTHOR]

Rhythmic oscillation is crucial for information transmission and neural communication among different brain areas. Stochastic resonance (SR) can evoke different patterns of neural oscillation. However, the characteristics of network resonance and underlying dynamical mechanisms are still unclear. In this paper, a biological model of cortical network is established and its dynamical response to external periodic stimulation is investigated. We explore the oscillatory resonance of excitatory and inhibitory populations in cortical network. It is found that the intrinsic parameters of neural populations determine the extent of resonant activity, indicating that the firing rate exhibits coherent oscillation when the frequency of external stimulation is close to intrinsic frequency of neural population. In addition, the nonlinear dynamics of cortical network in oscillatory resonance can be represented by helical manifolds in low-dimensional state space. The geometry of neural manifolds reveals the periodic dynamics and state transition in oscillatory resonance. Moreover, time delay in chemical synapses can induce multiple resonances, which appear intermittently at integer multiples of the period of input signal. The dynamical response of neural population achieves maximal periodically, due to the transition of network states induced by time delay. Furthermore, mean-field theory is applied to analyze theoretical dynamic of cortical networks with time delay and demonstrate the effective transmission of stimulation information via oscillatory resonance in the brain. Consequently, the obtained results contribute to the improvement of neuromodulation for neurological disease from the viewpoint of the neural basis. [ABSTRACT FROM AUTHOR]

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As nanotechnology advances, it is possible to build nanomachines to conduct tasks on the nano-scale. Since the EM wave, the traditional communication medium does not apply in nano-scale, Molecular Communication (MC) has been recently given increasing attention for its excellent biocompatibility and low energy consumption within the human body. Diffusion channel-based MC(DbMC) is mainly studied in the aquatic environment. However, due to the randomness of diffusion, DbMC suffers high losses, low propagation speed, and limited communication range. Directional Molecular Communication(DMC) is proposed by introducing chemotaxis. DMC can significantly improve the efficiency of molecular communication because it keeps molecules moving along a predetermined path. It is particularly suitable in the scenario of target tracking related to some applications such as drug delivery. In this paper, we have proposed a novel massive beacon coordinates system model to aid target tracking. Beacons in this system navigate nanomachines, and the beacon system can uniquely determine their position coordinates. Each nanomachine carries a lot of bacteria carrier (E.coli) to share information. Information is encoded in DNA molecules and transferred to other nanomachines by bacteria carriers. With the help of bacteria carriers, nanomachines can share their current position information with others to realize cooperated fast target tracking. We have evaluated its performance in target tracking through simulation by comparison with the diffusion-based model. Some key factors that may influence target tracking are also taken into consideration. [ABSTRACT FROM AUTHOR]

Dendrobium is the second biggest genus in the Orchidaceae family, some of which have both ornamental and therapeutic values. Alkaloids are a group of active chemicals found in Dendrobium plants. Dendrobine has emerged specific pharmacological and therapeutic properties. Although Dendrobium alkaloids have been isolated and identified since the 1930s, the composition of alkaloids and their biosynthesis pathways, including metabolic intermediates, alkaloid transporters, concrete genes involved in downstream pathways, and associated gene clusters, have remained unresolved scientific issues. This paper comprehensively reviews currently identified and tentative alkaloids from the aspect of biogenic pathways or metabolic genes uncovered based on the genome annotations. The biosynthesis pathways of each class of alkaloids are highlighted. Moreover, advances of the high-throughput sequencing technologies in the discovery of Dendrobium alkaloid pathways have been addressed. Applications of synthetic biology in large-scale production of alkaloids are also described. This would serve as the basis for further investigation into Dendrobium alkaloids. [ABSTRACT FROM AUTHOR]

In semiconductor manufacturing processes, yield analysis aims to increase the yield by determining and managing the causes of low yield. The variable data collected from semiconductor manufacturing processes, in which hundreds of unit processes are implemented according to specific conditions and sequences, are interdependent, and the variables related to previous processes influence the variables in subsequent processes. Therefore, the order of processes should be considered when building a model that searches for the causes of low yield. However, there have been few studies in this area. This paper proposes a low-yield root cause search method considering the order of processes using a long short-term memory with attention mechanism (LSTM-AM) model. Specifically, the LSTM-AM model is applied to data classified according to the process structure of semiconductor products, and the causes of low yield are determined considering the order of processes by extracting attention weights. Experiments are conducted to verify the suitability of the proposed method using real yield data from a semiconductor company. The experimental results confirm that the proposed method outperforms the existing low yield root cause search methods in terms of low yield prediction. [ABSTRACT FROM AUTHOR]