Leaching of metals and metalloids from highway marking glass beads and the potential environmental impact

Glass beads are embedded in pavement markings to obtain retroreflectivity which plays a crucial role in the lighting-up effect needed for safe driving. Elevated metal and metalloid concentrations of As, Sb, and Pb have recently been observed in imported glass beads. The main objective of this research was to assess the environmental impact associated with applying these imported glass beads in highway markings. To achieve this objective, total metal concentrations were measured using two techniques: hydrofluoric acid digestion followed by inductively coupled plasma mass spectroscopy (HF/ICP-MS), and field portable x-ray fluorescence (FP-XRF) spectroscopy. A number of leaching studies were conducted and included two standard United States Environmental Protection Agency (U.S. EPA) methods: the toxicity characteristic leaching procedure (TCLP) and the synthetic precipitation leaching procedure (SPLP). In addition, a factorial study was conducted to determine the impact of environmentally relevant factors such as pH, chemicals applied on roadways, particle size, and time on metal and metalloid leaching. To compare results among the three types of studies (TCLP, SPLP, and factorial study), a select batch of glass beads with elevated concentrations was used. FP-XRF was observed to be as reliable a tool for measuring total metal and metalloid concentrations and is recommended over the use of HF/ICP-MS. Results demonstrated that the most important factors affecting leaching were pH and time. For anions such as HAsO42- and SbO3-, leaching increased with increasing pH, while for cations including Pb2+, it increased as pH decreased. Sequential extraction was conducted as well to better understand the form of metals and metalloids associated with the glass beads. While 3% were extracted in the exchangeable (As, Mn, and Ba) and the oxidizable forms (Pb), greater than 97% of metals and metalloids were associated with the glass matrix. Further studies to assess leaching as a function of total concentration in the imported batch were conducted for 30 days. Non-parametric statistics were applied to test concentrations that resulted in excess of the groundwater quality criteria. Results demonstrated that the New Jersey Default Leachate Groundwater limits for As were exceeded for 98% of the samples tested. In case of Pb, these limits were exceeded for 58% of the samples and with Sb 15%. These results suggest a potential environmental impact to groundwater used as a drinking water source when either storing glass beads in bulk or disposing of the roadway marking material in bulk

In vitro evaluation of commercial probiotic products used for marine shrimp cultivation in Thailand

The objective of this study was to evaluate the effectiveness of 12 commercial probiotic products in Thailand, used in marine shrimp cultivation, based on two criteria namely, accuracy of the information on product labels as regards the number and types of microorganisms and acceptability of the number of probiotic microorganisms at 10,sup>6 colony forming unit (CFU)/g in the products. Of the 12 products sampled, only two of them provided adequate information on the number and composition of microorganisms and their proper dosage. In addition, none of the probiotic products possessed the correct number and composition of microorganisms or qualitative extracellular enzymes, declared on their labels nor did they show any in vitro inhibitory activity on shrimp pathogenic Vibrio harveyi. However, a few products were capable of biosynthesis of amylase, protease and lipase with high capacities.Key words: Commercial probiotic product, marine shrimp, Vibrio harveyi, amylase, protease, lipase

Mechanisms of DNA damage, repair, and mutagenesis

Living organisms are continuously exposed to a myriad of DNA damaging agents that can impact health and modulate disease-states. However, robust DNA repair and damage-bypass mechanisms faithfully protect the DNA by either removing or tolerating the damage to ensure an overall survival. Deviations in this fine-tuning are known to destabilize cellular metabolic homeostasis, as exemplified in diverse cancers where disruption or deregulation of DNA repair pathways results in genome instability. Because routinely used biological, physical and chemical agents impact human health, testing their genotoxicity and regulating their use have become important. In this introductory review, we will delineate mechanisms of DNA damage and the counteracting repair/tolerance pathways to provide insights into the molecular basis of genotoxicity in cells that lays the foundation for subsequent articles in this issue. Environ. Mol. Mutagen. 58:235–263, 2017 © 2017 Wiley Periodicals, Inc.National Institute of Environmental Health Sciences (Grant ES-015818

Online professional development programmes : reflections

The COVID-19 pandemic has brought a mixed bag of experiences with respect to teacher professional development programmes. While it has enabled many more persons to access training programmes at very low costs, it has also extensively changed the dynamics of the programmes, not necessarily for the better

Kink, singular soliton and periodic solutions to class of nonlinear equations

In this paper, we extend the ordinary differential Duffing equation into a partial differential equation. We study the traveling wave solutions to this model by using the G\u27/G expansion method. Then, based on the obtained results given for the Duffing equation, we generate kink, singular soliton and periodic solutions for a coupled integrable dispersionless nonlinear system. All the solutions given in this work are verified

Government initiatives towards the ‘training’ of teachers: principles and implementation

The teacher is central to all educational reform – this is the underlying principle of change in educational processes. Hence, an initiative to capacitate teachers is generally an adjunct to most government initiatives in education. The word adjunct is chosen with care – while the intent is to capacitate teachers to create change, somehow the teacher becomes a supplementary rather than a key player. A case in point is the implementation of continuous and comprehensive evaluation across States. A reinforcement of good pedagogy became a ‘programme’ with fixed templates and close monitoring in most states. From trust in the teacher and autonomy for her to help her students learn, we moved to what was resented as additional paperwork. While the reasons for a lack of trust in the teacher are many, ranging from systematic downgrading of the status of the teacher through top-down percolation of curricula, materials and processes, to the lack of facilitation within the ecosystem in which the teacher works, one manifestation is the perpetuation of outdated practices in our classrooms with ever worsening learning outcomes. The situation becomes even more ironical when one considers the multiple initiatives the government has created for the professional development of teachers, including the setting up of decentralised structures devoted entirely to this purpose. While these structures are meant to facilitate both pre- and in-service professional development of teachers, this article will restrict itself to initiatives related to in-service professional development or ‘training’, the term commonly used for formal activities involving learning in teachers

Seeking common ground – some debates related to education policy in India

Certain areas in education policy are subject to debate more than others. This article attempts to present a broad overview of the debates around investment in education, use of technology in teaching-learning, vocational education, teacher accountability and the no detention policy

Antibacterial activity of bacteriocin produced by Bacillus velezensis BUU004, herb extracts and their combination for controlling spoilage and pathogenic bacteria in dried, seasoned and crushed squid

Biopreservation is an attractive measure to maintain the quality and safety of food products simultaneously with fit in healthy lifestyle of consumers. This study aimed to evaluate biopreservative potential of bacteriocin produced by Bacillus velezensis BUU004, a mixture of lemongrass and hot pepper extracts, and their combination for controlling growths of spoilage bacteria and foodborne pathogens in dried, seasoned and crushed squid. The squid samples were treated with 1) sterile distilled water (control), 2) nisin solution, 3) semi-purified preparation containing bacteriocin from B. velezensis BUU004 (SPP-BV), 4) a mixture of lemongrass and hot pepper extracts, and 5) a combination of the SPP-BV and the mixed herb extracts. During 28-day storage, the three types of additives were as effective as commercial nisin for securing biosafety of the dried squid evident by a significant (p<0.05) reduction in total viable count, compared to the control. Administration of the tested additives every 14 days was more effective against spoilage bacteria in dried squid than a single treatment. Then, the tested additives were investigated their antibacterial activity against pathogenic E. coli, Salmonella Typhimurium and Bacillus cereus. The strongest inhibitory effect on all tested pathogens was observed with the combined addition of the SPP-BV and the mixed herb extracts in dried squid. SEM analysis revealed that the three additives had bactericidal activity through destruction of the bacterial cell walls. This study suggested that all tested additives had potential as an alternative for controlling food spoilage and pathogenic bacteria and enhancing the safety of dried seafood products

Design Web Based Ticketing System, for Menara Alor Star

Web based is the most famous portable technology, the WEB solution services can be obtained easily at any time in anywhere. That provides the crowed with the ticket for visit the Menara without losing time and effort. Web based allows to the users to use the Information Technology without being bound to a single location; it provides the users with the flexibility. In this study focused only to the development of a prototype for the Menara Alor Star e-ticketing. Reservation system comprises of a database that is built using MySQL database application software, Apache server as the web server and JSP as its application server. The methodology used is General Methodology using the Unified Modeling Language-UA Approach

Occurrence of Multidrug Resistant Methicillin-Resistant Staphylococcus aureus and Methicillin-Susceptibility Staphylococcus aureus in Chon Buri Province

บทคัดย่อ การศึกษาครั้งนี้มีจุดประสงค์เพื่อศึกษาความไวและแบบแผนการดื้อยาต้านจุลชีพของ Methicillin-resistant Staphylococcus aureus (MRSA) จำนวน 103 ไอโซเลท และ Methicillin-susceptibility Staphylococcus aureus (MSSA) จำนวน 136 ไอโซเลท ที่แยกได้จากผู้ป่วยในโรงพยาบาลชลบุรี และโรงพยาบาลสมเด็จพระบรมราชเทวี ณ ศรีราชา จังหวัดชลบุรี พบว่า พบว่า MSSA ทุกไอโซเลทมีความไวต่อยาต้านจุลชีพ Oxacillin, Cefoxitin, Cefuroxime และ Vancomycin และเกือบทุกไอโซเลทดื้อต่อ Penicillin G และ Ampicillin ยกเว้น MSSA ที่แยกได้จากโรงพยาบาลชลบุรี คิดเป็น 2.88% เท่ากัน ส่วน MRSA ทุกไอโซเลทที่แยกได้จากทั้ง 2 โรงพยาบาล มีความไวต่อ Vancomycin และดื้อต่อ Penicillin G, Ampicillin, Oxacillin และ Cefoxitin ส่วนแบบแผนการดื้อยาหลายชนิดของ MRSA ที่แยกได้จากโรงพยาบาลสมเด็จพระบรมราชเทวี ณ ศรีราชา และโรงพยาบาลชลบุรี พบว่ามีแบบแผนการดื้อยาต้านจุลชีพมากกว่า 6 ชนิดขึ้นไปมากที่สุด คิดเป็น 94.74% และ 97.62% ตามลำดับ และ MSSA มีแบบแผนการดื้อต่อยาต้านจุลชีพ 3 ชนิดมากที่สุด คิดเป็น 71.87% และ 60.58% ตามลำดับ จากการศึกษาครั้งนี้ชี้ให้เห็นว่าทั้ง MRSA และ MSSA ที่คัดแยกมาจากจังหวัดชลบุรีมีการดื้อต่อยาต้านจุลชีพหลายชนิด  โดยเฉพาะอย่างยิ่ง MRSA ดื้อต่อยาต้านจุลชีพในกลุ่มเบต้าแลคแตมมากที่สุด คำสำคัญ: Methicillin-resistant Staphylococcus aureus (MRSA)Methicillin-susceptibility Staphylococcus aureus (MSSA) ความไวต่อยาต้านจุลชีพ การดื้อยาปฏิชีวนะหลายชนิด ABSTRACTThe aim of this study was to investigate the antimicrobial susceptibility and pattern of multidrug resistance of methicillin-resistant Staphylococcus aureus (MRSA; 103 isolates) and methicillin-susceptibility Staphylococcus aureus (MSSA; 136 isolates) recovered from the patients in Chon Buri Hospital and Queen Savang Vadhana Memorial Hospital in Chon Buri Province. All isolates of MSSA were susceptible to oxacillin, cefoxitin, cefuroxime and vancomycin. Almost all MSSA isolates were resistant to penicillin G and ampicillin, except 2.88% MSSA isolated from Chon Buri Hospital. All MRSA isolates recovered from both hospitals exhibited susceptibility to vancomycin and were resistant to penicillin G, ampicillin, oxacillin and cefoxitin. In case of antimicrobial resistant pattern of S. sureus isolated from Queen Savang Vadhana Memorial Hospital and Chon Buri Hospital, MRSA showed the highest resistance to more than 6 types of antimicrobial agents (94.74% and 97.62%, respectively) while MSSA presented the highest resistance to 3 types of those agents (71.87% and 60.58%, respectively). This finding indicated that both MRSA and MSSA collected from hospitals in Chon Buri Province were resistant to multiple antimicrobial agents, particularly, beta-lactam antibiotics resistance of MRSA.Keywords: Methicillin-resistant Staphylococcus aureus (MRSA), Methicillin-susceptibility Staphylococcus aureus (MSSA), Antimicrobial susceptibility, Multidrug resistan