The production technology of mineral soda alumina glass: A perspective from microstructural analysis of glass beads in Iron Age Taiwan.

Mineral soda alumina (m-Na-Al) glass is a common glass production group found around the Indo-Pacific region. In Iron Age Taiwan, its presence dates back to the early 1st millennium AD. This research discusses m-Na-Al glass beads excavated from Iron Age sites in Taiwan. No production sites for m-Na-Al have been found, but microstructural analysis suggests m-Na-Al glass appears to originate around South Asia and is exchanged widely. SEM-EDS and EPMA were used to analyse red, orange, yellow, green and blue m-Na-Al glass. The microstructure of the glass shows the presence of plagioclase and alkali feldspar relics in the glass, suggesting a low manufacturing temperature. Copper-based colourants are identified in red, orange, blue and green glass, while lead tin oxide is used in yellow and green glass. It appears that various types of copper-containing raw materials were procured by craftspeople, and a self-reduction process for producing red and orange glass is tentatively proposed. Additionally, the microstructure of yellow glass reveals different colouring paths were used. These results increase our understanding of the selection of raw materials, and provide an impetus for further research on the cross craft interaction between glass and copper production.

SARS-CoV-2 Survival on Surfaces and the Effect of UV-C Light.

The aim of this study was to establish the persistence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on inanimate surfaces such as plastic, stainless steel, and glass during UV-C irradiation which is a physical means commonly utilized in sanitization procedures. The viral inactivation rate, virus half-life, and percentage of titer reduction after UV-C irradiation were assessed. Infectivity was maintained on plastic and glass until 120 h and on stainless steel until 72 h. The virus half-life was 5.3, 4.4, and 4.2 h on plastic, stainless steel, and glass, respectively. In all cases, titer decay was >99% after drop drying. UV-C irradiation efficiently reduced virus titer (99.99%), with doses ranging from 10.25 to 23.71 mJ/cm2. Plastic and stainless steel needed higher doses to achieve target reduction. The total inactivation of SARS-CoV-2 on glass was obtained with the lower dose applied. SARS-CoV-2 survival can be long lasting on inanimate surfaces. It is worth recommending efficient disinfection protocols as a measure of prevention of viral spread. UV-C can provide rapid, efficient and sustainable sanitization procedures of different materials and surfaces. The dosages and mode of irradiation are important parameters to consider in their implementation as an important means to fight the SARS-CoV-2 pandemic.

Evaluation of Stoffenmanager and a New Exposure Model for Estimating Occupational Exposure to Styrene in the Fiberglass Reinforced Plastics Lamination Process.

This study aims to evaluate occupational exposure models by comparing model estimations of Stoffenmanager, version 8.2, and exposure scores calculated using a new exposure model with personal exposure measurements for styrene used in the fiberglass-reinforced plastic (FRP) lamination processes in Korea. Using the collected exposure measurements (n = 160) with detailed contextual information about the type of process, working conditions, local exhaust ventilation, respiratory protections, and task descriptions, we developed a new model algorithm to estimate the score for occupational exposures on situation level. We assumed that the source of exposure originates from the near field only (within the breathing zone of workers). The new model is designed as a simple formula of multiplying scores for job classification, exposure potential, engineering controls, chemical hazard, and exposure probability and then dividing the score for workplace size. The final score is log-transformed, ranging from 1 to 14, and the exposure category is divided into four ratings: no exposure (1), low (2), medium (3), and high (4) exposures. Using the contextual information, all the parameters and modifying factors are similarly entered into the two models through direct translation and coding processes with expert judgement, and the exposure estimations and scores using the two models are calculated for each situation. Overall bias and precision for Stoffenmanager are -1.00 ± 2.07 (50th) and -0.32 ± 2.32 (90th) for all situations (n = 36), indicating that Stoffenmanager slightly underestimated styrene exposures. Pearson's correlation coefficients are significantly high for Stoffenmanager (r = 0.87) and the new model (r = 0.88), and the correlation between the two models is significantly high (r = 0.93) (p < 0.01). Therefore, the model estimations using Stoffenmanager and the new model are significantly correlated with the styrene exposures in the FRP lamination process. Further studies are needed to validate and calibrate the models using a larger number of exposure measurements for various substances in the future.

Ultrathin glass fiber microprobe for electroporation of arbitrary selected cell groups.

A new type of ultrathin fiber microprobe for selective electroporation is reported. The microprobe is 10 cm long and has a diameter of 350 µm. This microprobe is a low cost tool, which allows electroporation of an arbitrary selected single cell or groups of cells among population with use of a standard microscope and cell culture plates. The microprobe in its basic form contains two metal microelectrodes made of a silver-copper alloy, running along the fiber, each with a diameter of 23 µm. The probe was tested in vitro on a population of normal and cancer cells. Successful targeted electroporation was observed by means of accumulation of trypan blue (TB) dye marker in the cell. The electroporation phenomenon was also verified with propidium iodide and AnnexinV in fluorescent microscopy.

Beach litter distribution along the western Mediterranean coast of Spain.

The amount and composition of beach litter was assessed, during spring 2018, at 56 sites along the coast of Alicante Province, on the western Mediterranean Sea. Selected sites covered "natural" (19), "village" (17) and "urban" (20) bathing areas and a total of 10,101 litter items was counted in an area of 201,686 m2. Plastic represented the dominant material with 8345 items, i.e. 82.6% of all debris; paper and cardboard numbered 566 items (i.e. 5.6%); pottery and ceramics 348 (3.4%); metal 325 (3.2%); cloth 231 (2.3%); glass 147 (1.5%); rubber 64 (0.6%); wood 46 (0.5%) and other materials summed 29 items, i.e. 0.3% of all debris. Cigarette butts, 45.6% of total items, were observed at different coastal sites: i.e. 1028 units at natural, 1148 at village and 2431 at urban sites. Despite the efforts of local administrations, which enforced cleaning operations at most sites, litter items were essentially related to beachgoers followed by wastewater discharges and fishing activities.

Plastic Pirates sample litter at rivers in Germany - Riverside litter and litter sources estimated by schoolchildren.

Rivers are an important source of marine anthropogenic litter, but the particular origins of riverine litter itself have not been well established. Here we used a citizen science approach where schoolchildren examined litter at riversides and identified possible sources at over 250 sampling spots along large and small rivers in Germany, during autumn 2016 and spring 2017. Litter densities have an overall median of 0.14, interquartile range 0-0.57 items m-2 and an overall average (±standard deviation) of 0.54 ±â€¯1.20 litter items m-2. Litter quantities differed only little by sampling year. The principal litter types found were plastics and cigarette butts (31% and 20%, respectively), followed by glass, paper, and metal items, indicating recreational visitors as the principal litter source. At many sites (85%), accumulations of litter, consisting principally of cigarettes and food packaging, have been found. At almost all sampling sites (89%), litter potentially hazardous to human health has been observed, including broken glass, sharp metal objects, used personal hygiene articles and items containing chemicals. In the search for litter sources, the schoolchildren identified mainly people who use the rivers as recreational areas (in contrast to residents living in the vicinity, illegal dumping, or the river itself depositing litter from upstream sources). These results indicate the urgent need for better education and policy measures in order to protect riparian environments and reduce input of riverine litter to the marine environment.

Evaluation of the effects of initial water temperature and curing time on fiberglass cast strength.

OBJECTIVE: To determine the effects of water temperature and cure time on cast strength. STUDY DESIGN: Prospective randomized experimental study. METHODS: Two water temperatures were tested, 23°C (cold) and 42°C (warm). Cast constructs were made of 4-inch fiberglass casting material over a rubber mandrel. Each construct was divided into 3 segments and tested in 4-point bending at 0.5, 1, and 24 hours. Stiffness and bending moment, cumulative energy, and angular deformation at yield and failure were recorded and analyzed by using repeated measures ANOVA. RESULTS: Mean time ± SD to complete the construct was 2.2 ± 0.8 and 2.3 ± 0.6 minutes for warm and cold water, respectively. Warm water and longer cure times produced constructs with greater stiffness (23.05 vs 20.88 newton-meter degrees [Nm°] at 0.5 hours), bending moment (121.75 vs 107.31 Nm° at 0.5 hours), and cumulative energy (557.33 vs 428.89 Nm° at 1 hour) at yield and failure. Longer cure time significantly increased angular deformation of rods at failure; however, water temperature did not. In general, the strongest casts were produced with warm water and after curing for 24 hours. CONCLUSION: Fiberglass casts continued to gain strength for at least 24 hours. Use of warm water increased the rate of curing, resulting in stronger constructs at earlier time points. CLINICAL SIGNIFICANCE: Use of warm water is recommended to initiate fiberglass cast curing, especially if the casted limb will be loaded soon after cast application.

Are glass fiber particles released during the use of electronic cigarettes? Development of a semi-quantitative approach to detect glass particle emission due to vaping.

This study investigated the emission characteristics of glass particles resulting from smoking electronic cigarettes (ECs). First, the most suitable filter for the collection of glass particles was explored by examining the performance (reliability) of various types of filters. A polycarbonate filter was determined as the optimum choice to collect glass particles in EC aerosol. A cartomizer was filled with EC refill solution composed of an equal volume of propylene glycol (PG) and vegetable glycol (VG). To simulate the potential conditions for glass particle emission, EC vaped aerosols were collected at three distinctive puffing intervals: (1) 0-10 puffs, (2) 101-110 puffs, and (3) 201-210 puffs (flow rate of 1 L min-1, 2 s per puff, and 10 puffs per sample). Glass particles were observed as early as after 100 times puffing from certain products, while after 200 from others. Thus, glass particles were generated by increasing the number of puffs and usage of the EC cartomizer. The analysis of glass particles collected onto polycarbonate filters by scanning electron microscopy (SEM)/energy dispersive X-ray spectroscopy (EDS) confirmed the presence of glass particles in samples collected after puffing 100-200 times. The study demonstrated that the possibility of glass particle emissions from the EC device increased considerably with the increasing number of total puffs.

Development of an HPLC/UV method for the evaluation of extractables and leachables in plastic: Application to a plastic-packaged calcium gluconate glucoheptonate solution.

Calcium gluconate glucoheptonate (GGCa) is known to interact with glass containers, leading to the leaching of aluminum from the glass into the solution at toxic level. Therefore, plastic containers seem to be a preferable packaging alternative. Nevertheless, plastics contain potentially toxic additives which could be released into the solution. In order to study content container interaction between GGCa and two plastic containers (polypropylene PP and polyethylene PE containers), an HPLC-PDA method was developed to separate, detect and quantify eleven additives commonly found in plastic materials, with good limit of detection and quantification. This method was then applied to evaluate the compatibility between GGCa and the two plastic containers. After 3 months of storage at 25 °C, none of the eleven additives were detected in GGCa solutions. The safety concern threshold (SCT) and of the analytical evaluation threshold (AET) were evaluated to discriminate the need to identify and qualify unknown peaks.

Avaliação histométrica e histoquímica de vidro bioativo no processo de reparação óssea / Histométrica assessment and histochemistry of bioactive glass in the process of bone repair

Os enxertos de origem autógena são osteogênicos e possuem como vantagens a produção de tecido ósseo originário do próprio organismo. A sua limitação é a grande morbidade cirúrgica. O biovidro é uma cerâmica bioativa com disponibilidade ilimitada que leva a uma cirurgia com menor morbidade. O presente estudo teve como objetivo avaliar o biovidro teste durante o reparo ósseo e compará-lo com outros substitutos ósseos, em defeitos cirúrgicos experimentais em tíbia de ratos. O biovidro teste (CEELBIO, Belo Horizonte, Brasil), previamente caracterizado foi comparado com o Biogran® (Biomet 3i Inovattions Inc., Palm Beach Gardens, USA), através de espectroscopia na região do infravermelho, microscopia eletrônica de varredura (MEV), espectroscopia de dispersão em energia (EDS) e fluorescência de Rx. Após as análises estruturais, deu-se início ao estudo in vivo. Foram utilizados 120 ratos (rattus norvegicus albinus, Wistar) machos, com aproximadamente 7 a 8 semanas. Os defeitos ósseos foram realizados na tíbia direita dos animais e preenchidos de acordo com a seguinte divisão: Grupo I- controle negativo, sem preenchimento; Grupo II- foi preenchido por Biogran®; Grupo III- preenchido por biovidro teste; Grupo IVcontrole positivo, com preenchimento com osso autógeno. Nos períodos de 7, 14, 21, 28, 49 e 70 dias pós-operatório, os animais foram eutanasiados e os processos de mineralização óssea e reparo foram analisados através de histomorfometria (% de osso neoformado no sítio do defeito). Níveis de BMP-2 foram mensurados através de ensaio de ELISA. Análise estatística foi realizada utilizando programa SPSS (versão 20.0, SPSS Inc., Chicago, USA). Os resultados da análise histológica demonstraram que, no controle negativo, houve neoformação óssea até os 14 dias (20,40%, p<0,001) e depois houve reabsorção em até 21 dias (6,60%, p<0,001). No grupo de Biogran®, houve uma neoformação óssea junto aos grãos em 7 dias (34,20%, p= 0,019) e que se manteve enquanto o material estava presente nos defeitos em 70 dias (15,67%, p= 0,048). O biovidro teste foi reabsorvido totalmente até 21 dias e os picos de osso neoformado foram observados em 7 (21,00%, p= 0,019) e 49 dias (15,60%, p= 0,036). Nesse grupo, células semelhantes a macrófagos, dispostas em lençol, foram visualizadas junto a tecido ósseo neoformado. Quanto ao controle positivo, o osso autógeno foi totalmente reabsorvido em até 14 dias e o pico de formação óssea se deu nesse 9 mesmo momento, em 14 dias, (40,80%, p<0,001), mostrando-se, nos tempos subsequentes, similar ao controle negativo. Células gigantes multinucleadas foram encontradas em áreas de remodelação óssea, junto ao Biogran® e ao biovidro teste. Os níveis de BMP-2 no grupo controle negativo se mostraram maiores nos tempos de 7 (418,80pg/mL, p= 0,871) e 28 dias (346,36 pg/mL, p= 0,035). No grupo Biogran® o pico de BMP-2 se deu em 7 dias (471,95 pg/mL, p= 0,871). O biovidro teste teve seu pico de liberação de BMP-2 em 7 dias também (471,39 pg/mL, p= 0,871). Já o controle positivo apresentou nível de BMP-2 em maior quantidade nos tempos de 7 (346,55 pg/mL, p= 0,871) e 21 dias (407,57 pg/mL, p= 0,300). O biovidro é um material degradável, e com características biológicas de osteoindução e osteocondução

The autogenous origin grafts are osteogenic and have the advantage of producing bone tissue originated from the body itself. Its limitation is the great surgical morbidity. The bioglass is a bioactive ceramic with unlimited availability that leads to a surgery with less morbidity. This study aimed to evaluate the bioglass test during bone repair and to compare it with other bone substitutes in experimental surgical defects in the tibia of rats. The bioglass test (CEELBIO, Belo Horizonte, Brazil), has been characterized and compared to the Biogran® (Biomet 3i Inovattions Inc., Palm Beach Gardens, USA) by spectroscopy in the infrared, scanning electron microscopy (SEM), EDS spectroscopy and Rx fluorescence. The study in vivo has been started after the structural analysis. 120 rats (Rattus norvegicus albinus, Wistar rats), with approximately 7 to 8 weeks, were used. The bone defects were performed in the right tibia of animals and filled according to the following breakdown: Group I- negative control without filling; Group II- filled by Biogran®; Group III- filled with bioglass test; IV- positive control group, with filling of autogenous bone. At 7, 14, 21, 28, 49 and 70 postoperative days, the animals were euthanized and bone mineralization processes and repair were analyzed by histomorphometry (% of newly formed bone in the defect site). BMP-2 levels were measured by ELISA assay. Statistical analysis was performed using SPSS (version 20.0, SPSS Inc., Chicago, USA). The results of the histological analysis showed that in the negative control there was no bone growth up to 14 days (20.40%, p <0.001) and after reabsorption, within 21 days (6.60%, p <0.001). In Biogran® group, there was new bone formation along the grain in 7 days (34.20%, p = 0.019) and that was maintained as the material was present in shortcomings in 70 days (15.67%, p = 0.048) . The test bioglass was completely reabsorbed within 21 days; new bone formation and peaks were observed in 7 (21.00%, p = 0.019) and 49 days (15.60%, p = 0.036). In this group, macrophage-like cells arranged in sheets, were viewed with the newly formed bone. On the positive control, autologous bone was completely reabsorbed within 14 days, and the peak bone formation occurred at the same moment, within 14 days (40.80%, p <0.001), showing, in subsequent occasions, similar to control negative. Multinucleated giant cells were found in areas of bone remodeling, with the Biogran® and test bioglass. BMP-2 levels in the negative control group were higher in 7 (418,80pg / ml, p = 11 0.871) and 28 days (346.36 pg / ml, p = 0.035). In Biogran® group peak BMP-2 occurred within 7 days (471.95 pg / ml, p = 0.871). The test bioglass had its peak BMP-2 release in 7 days as well (471.39 pg / ml, p = 0.871). The positive control showed BMP-2 level in greater quantities in 7 (346.55 pg / ml, p = 0.871) and 21 days (407.57 pg / ml, p = 0.300). The test bioglass is a biodegradable material, with biological characteristics of osteoinduction and osteoconduction

Evaluation of fiber reinforced cement using digital image correlation.

The effect of short fiber reinforcements on the mechanical properties of cement has been examined using a splitting tensile - digital image correlation (DIC) measurement method. Three short fiber reinforcement materials have been used in this study: fiberglass, nylon, and polypropylene. The method outlined provides a simple experimental setup that can be used to evaluate the ultimate tensile strength of brittle materials as well as measure the full field strain across the surface of the splitting tensile test cylindrical specimen. Since the DIC measurement technique is a contact free measurement this method can be used to assess sample failure.

A Ni-free ZrCuFeAlAg bulk metallic glass with potential for biomedical applications.

The mechanical properties and biocompatibility of an Ni-free Zr-based bulk metallic glass (BMG) Zr60.14Cu22.31Fe4.85Al9.7Ag3 were investigated in detail to evaluate its potential as a biomaterial. The BMG was found to have a low Young's modulus of 82±1.9GPa, a high strength of 1720±28MPa and a high fracture toughness of 94±19MPam(1/2), as well as good fatigue strength over 400MPa. The corrosion behavior of the alloy was investigated in simulated body fluid (SBF) by electrochemical measurements, which indicates that the Zr-based BMG has a better corrosion resistance than pure Zr and Ti6Al4V. X-ray photoelectron spectroscopy analysis revealed that the passive film formed on the BMG surface is enriched in Al- and Zr-oxides, which could account for the good corrosion resistance of the BMG. On the other hand, metal ion release of the BMG in SBF was determined by inductively coupled plasma mass spectrometry after the BMG was immersed in SBF at 37°C for 30days, showing a ppb (ngml(-1)) level of metal ion release. The in vitro test via cell culture indicates that the BMG exhibits a cytotoxicity of Grade 0-1, which is as good as Ti6Al4V alloy. Cell adhesion morphological analysis shows that the cells were flattened and well spread out on the surfaces of the BMG, showing that the BMG had good biocompatibility. The combination of good mechanical properties and biocompatibility demonstrates that the Ni-free Zr-based BMG studied in this work is a good candidate for a new type of load-bearing biomedical material.

Evaluation of decontamination efficacy of cleaning solutions on stainless steel and glass surfaces contaminated by 10 antineoplastic agents.

OBJECTIVES: The handling of antineoplastic agents results in chronic surface contamination that must be minimized and eliminated. This study was designed to assess the potential of several chemical solutions to decontaminate two types of work surfaces that were intentionally contaminated with antineoplastic drugs. METHODS: A range of solutions with variable physicochemical properties such as their hydrophilic/hydrophobic balance, oxidizing power, desorption, and solubilization were tested: ultrapure water, isopropyl alcohol, acetone, sodium hypochlorite, and surfactants such as dishwashing liquid (DWL), sodium dodecyl sulfate (SDS), Tween 40, and Span 80. These solutions were tested on 10 antineoplastic drugs: cytarabine, gemcitabine, methotrexate, etoposide phosphate, irinotecan, cyclophosphamide, ifosfamide, doxorubicin, epirubicin, and vincristine. To simulate contaminated surfaces, these molecules (200ng) were deliberately spread onto two types of work surfaces: stainless steel and glass. Recovered by wiping with a specific aqueous solvent (acetonitrile/HCOOH; 20/0.1%) and an absorbent wipe (Whatman 903®), the residual contamination was quantified using high-performance liquid chromatography (HPLC) coupled to mass spectrometry. To compare all tested cleaning solutions, a performance value of effectiveness was determined from contamination residues of the 10 drugs. RESULTS: Sodium hypochlorite showed the highest overall effectiveness with 98% contamination removed. Ultrapure water, isopropyl alcohol/water, and acetone were less effective with effectiveness values of 76.8, 80.7, and 40.4%, respectively. Ultrapure water was effective on most hydrophilic molecules (97.1% for cytarabine), while on the other hand, isopropyl alcohol/water (70/30, vol/vol) was effective on the least hydrophilic ones (85.2% for doxorubicin and 87.8% for epirubicin). Acetone had little effect, whatever the type of molecule. Among products containing surfactants, DWL was found effective (91.5%), but its formulation was unknown. Formulations with single surfactant non-ionics (tween 40 and span 80) or anionic (SDS) were also tested. Finally, solutions containing 10(-2) M anionic surfactants and 20% isopropyl alcohol had the highest global effectiveness at around 90%. More precisely, their efficacy was the highest (94.8%) for the most hydrophilic compounds such as cytarabine and around 80.0% for anthracyclines. Finally, the addition of isopropyl alcohol to surfactant solutions enhanced their decontamination efficiency on the least hydrophilic molecules. Measured values from the stainless steel surface were similar to those from the glass one. CONCLUSION: This study demonstrates that all decontamination agents reduce antineoplastic contamination on work surfaces, but none removes it totally. Although very effective, sodium hypochlorite cannot be used routinely on stainless steel surfaces. Solutions containing anionic surfactant such as SDS, with a high efficiency/safety ratio, proved most promising in terms of surface decontamination.

Estimation of past radon exposure to indoor radon from embedded (210)Po in household glass.

In the present investigation, the surface-deposited polonium activities were measured in houses in the Ukhimath region of Garhwal Himalaya, India. The surface-deposited (210)Po activity concentrations were found to vary from 0.7 to 15.40 Bq m(-2) with an average of 5.95 Bq m(-2). The radon concentration estimated on the basis of (210)Po activity was found to vary from 0.29 to 700 Bq m(-3) with an average value 242 Bq m(-3). The contemporary radon concentration in the area was found to vary from 13 to 181 Bq m(-3) with an average of 46 Bq m(-3). The annual effective dose due to (210)Po activity in houses in the Garhwal Himalaya region was found to vary from 0.61 to 13.33 mSv with an average of 5.15 mSv. Some worldwide studies have shown the relation between the increased risk of lung cancer and smoking habits. Data on smoking have also been collected from the same dwellings. The significance of this work is also discussed in detail from a radiation protection point of view.

Influência da velocidade no torque de remoção de tampas plásticas rosqueáveis para produtos farmacêuticos / Influence of the speed on the removal torque of plastic screw caps for pharmaceutical products

O estudo teve por objetivo avaliar a influência da velocidade empregada durante a determinação do torque de aplicação e remoção de tampas plásticas rosqueáveis de polipropileno (PP), com vedante interno, aplicadas em frascos de vidro e de poli(tereftalato de etileno) (PET) para produtos farmacêuticos, com diâmetros de terminação de 24 e 28 mm. Foi verificada também a influência do material de embalagem (vidro ou PET) e do diâmetro da terminação no torque de retenção estático e dinâmico (após simulação de transporte) em intervalos de tempo após 24 e 48 horas e após 7, 14 e 28 dias da aplicação dos respectivos sistemas de fechamento. Verificou-se que a velocidade não apresenta influência no torque de aplicação desde que o valor máximo seja controlado durante o processo de fechamento da tampa. No torque de remoção imediato, entretanto, a velocidade influencia significativamente nos resultados, sendo recomendado, sempre que possível, a utilização de uma velocidade constante. Foi estabelecido para o estudo a velocidade de 5 rpm para evitar a influência desse parâmetro nos resultados de torque obtidos. O material de embalagem e o diâmetro da terminação evidenciaram influência significativa nos resultados de torque de retenção estático e dinâmico, sendo observados valores superiores para os frascos de vidro comparativamente aos frascos de PET. Esse desempenho pode estar associado às diferenças nas propriedades viscoelásticas e na força de fricção ou atrito entre os materiais da tampa com vedante e a embalagem.

The objective of this study was to ascertain the influence on the measured torque of the speed employed during the tightening and removal of polypropylene (PP) screw caps, with internal liners, used on glass and polyethylene terephthalate (PET) bottles for pharmaceutical products, with mouth diameters of 24 and 28 mm. The influence of the packaging material (glass or PET) and mouth diameter on the static and dynamic torque retention was observed (after transport simulation) at time intervals after 24 and 48 hours and after 7, 14 and 28 days of torque application to each closure system. It was found that the speed did not influence the tightening torque since the torque is controlled during the closing process. However, the speed significantly influenced the immediate removal torque and it is preferable to use a constant speed whenever possible. It was found that a speed of 5 rpm was best, to prevent this parameter affecting the torque results. The packaging material and mouth diameter exerted a significant influence on the retention torque, both in the static and dynamic tests, and higher torques were observed for glass than for PET bottles. This performance may be related to viscoelastic properties and the friction between the lined cap and the packaging material.

Potencial de remineralización ultraestructural del vidrio bioactivo versus fluoruro estañoso / Ultrastructural remineralization potential of stannous fluoride versus bioactive glass

Esta investigación fue determinar el potencial de remineralización a nivel ultraestructural del vidrio bioactivo (VBio) en comparación al producido por el fluoruro estañoso (FSn). Se recolectaron 10 molares humanos del servicio CAMIULA. Se dividieron en 4 partes con sierra de precisión: Grupo A (Superficie no tratada control), Grupo B (Superficie desmineralizada control), Grupo C (Superficie con VBio), Grupo D (Superficie con FSn). Los grupos B, C, D fueron sometidos a desmineralizaron en una solución acuosa de metilcelulosa al 8% (1500cP, 63 kDa) cubierta con un volumen igual de 0.1 mol/1 de acido láctico, pH ajustado con KOH; por un periodo de 5 días a un pH de 4.6 a 37 ºC. Posteriormente el Grupo C fue sometido a régimen de remineralización con Biogran® (Biomet 3iTM) a una concentración de 5wT% 2 veces al día por 15 días; igualmente el Grupo D se sometió de fluoruro estañoso Gel Kam (Colgate Palmolive®) al 0,4% 2 veces al día por 15 días. Las muestras de cada grupo fueron preparadas para SEM y para el análisis de elementos mediante EDS (O, P, Ca, Sn y Si). Los datos del EDS se analizaron con ANOVA Univariante para la diferencia en el porcentaje de elementos en 2 niveles (Elementos, Tratamiento). Los datos del SEM para las variables disminución de poros (DP) y espacios (DE) en función del tratamiento con prueba del chi-cuadrado (X2) , del paquete estadístico SPSS 19. El valor de alfa fue establecido en 0.05. La diferencia en el porcentaje de elementos promedio de cada elemento y la desviación estándar (±SD) se muestran a continuación: Grupo VBio: O= -0,89 (6,19); P= -0,39 (1,26); Ca 0,99 (5,19); Si 0,07 (0,09) y Grupo FSn: O= -5,97 (8,4); P= -1,16 (1,4); Ca -5,14 (3,95); Sn 12,19 (5,66). El ANOVA, nivel Tratamiento p= 0,977, sin diferencias significativas. El nivel Elementos el valor de p= 0,000, con diferencias significativas. La variable DP con IC: 95%= 34,65 - 93,5% en ambos tratamientos, el X2 p=1 sin diferencias significativas...

To determine the potential for remineralization at an ultraestructural level of Bioactive glass (VBio) when compared to stannous fluoride (FSn). 10 human molars were collected from CAMIULA (a dentistry service of the University of Los Andes, Venezuela). The teeth were divided in four parts with a precision saw: Group (untreated surface - control), Group B (demineralized surface - control), Group C (Surface with VBio), Group D (Surface with FSn). Groups B, C and D were submitted to demineralization in a 8% metilcelulose aqueous solution (1500cP, 63 kDa) covered with an equal volume of 0.1 mol/1 of lactic acid, with an adjusted pH with KOH at 4.6 a 37 ºC for a 5-days period. Later, Group C was exposed to a remineralization regime with Biogran® (Biomet 3iTM) at a 5wT% concentration twice a day 2 for 15 days. Likely, Group D was exposed to a regime with stannous fluoride Gel Kam (Colgate Palmolive®) at 0,4% 2 twice a day for 15 days. The samples from each group were prepared for SEM and the elements analysis through EDS (O, P, Ca, Sn y Si). Data from EDS were analyses with Univariant ANOVA for the difference in the percentage of elements at two levels (Elements, Treatment). Data from SEM for the variables porosity diminish and spaces (DP and DE, respectively) in relation to treatment with Chi Squared X2 , by using the statistics package SPSS 19. Significance level was established at 0.05. Differences in the percentage of average elements of each element and standard deviation (±SD) were as follow: VBio Group: O= -0,89 (6,19); P= -0,39 (1,26); Ca 0,99 (5,19); if 0,07 (0,09) and FSn Group: O= -5,97 (8,4); P= -1,16 (1,4); Ca -5,14 (3,95); Sn 12,19 (5,66). ANOVA results showed treatment level p= 0,977, with no statistically significant differences. The Elements there were statistically significant differences (p= 0,000). The variable DP with IC: 95%= 34, 65 - 93,5% for both treatment; X2 p=1 showed no statistically significant differences....

Endocrine disruptors in bottled mineral water: estrogenic activity in the E-Screen.

Human exposure to endocrine disruptors is well documented by biomonitoring data. However, this information is limited to few chemicals like bisphenol A or phthalate plasticizers. To account for so-far unidentified endocrine disruptors and potential mixture effects we employ bioassays to detect endocrine activity in foodstuff and consequently characterize the integrated exposure to endocrine active compounds. Recently, we reported a broad contamination of commercially available bottled water with estrogenic activity and presented evidence for the plastic packaging being a source of this contamination. In continuation of that work, we here compare different sample preparation methods to extract estrogen-like compounds from bottled water. These data demonstrate that inappropriate extraction methods and sample treatment may lead to false-negative results when testing water extracts in bioassays. Using an optimized sample preparation strategy, we furthermore present data on the estrogenic activity of bottled water from France, Germany, and Italy: eleven of the 18 analyzed water samples (61.1%) induced a significant estrogenic response in a bioassay employing a human carcinoma cell line (MCF7, E-Screen). The relative proliferative effects ranged from 19.8 to 50.2% corresponding to an estrogenic activity of 1.9-12.2 pg estradiol equivalents per liter bottled water. When comparing water of the same spring that is packed in glass or plastic bottles made of polyethylene terephthalate (PET), estrogenic activity is three times higher in water from plastic bottles. These data support the hypothesis that PET packaging materials are a source of estrogen-like compounds. Furthermore, the findings presented here conform to previous studies and indicate that the contamination of bottled water with endocrine disruptors is a transnational phenomenon.

Radiological implications of the use of uranium in vaseline glass.

Uranium oxides have been used as colourants in glassware since the 19th century and this type of glass is commonly referred to as vaseline glass. There are many collectors of vaseline glass in the UK who obtain pieces from the UK antiques market or from abroad. Dose rate measurements were made for a number of items of vaseline glass, and the uranium content of one item was measured. Potential doses to collectors were considered, along with implications for trade and transport due to the uranium content of the glassware. It was concluded that generally items of vaseline glass could give rise to low skin doses from beta radiation, though frequent wearing of necklaces made from vaseline glass may lead to doses in excess of the HPA (Health Protection Agency) dose criterion for consumer products that are not related to safety. Registration under the Radioactive Substances Act will not be required and almost all items of vaseline glass should be suitable for sending through the Royal Mail. For those items not accepted by Royal Mail, it is understood that the transport regulations for radioactive materials would not apply.

The recycling of comminuted glass-fiber-reinforced resin from electronic waste.

The reuse of comminuted glass-fiber-reinforced resin with various granularities gathered from printed circuit manufacturing residues was investigated. As fillers, these residues were converted into polymeric composite board by an extrusion and injection process using polypropylene as a bonding agent. The mechanical properties of the reproduced composite board were examined by considering the effects of mass fraction and glass-fiber distribution. Interfacial-layer micrograph analysis of the composite material fracture surface was used to study the fiber reinforcement mechanism. Results showed that using comminuted glass-fiber-reinforced resin as a filler material greatly enhanced the performance properties of the composite board. Although the length and diameter of filler varied, these variations had no appreciable effect on the mechanical properties of the processed board. Maximum values of 48.30 MPa for flexural strength, 31.34 MPa for tensile strength, and 31.34 J/m for impact strength were achieved from a composite board containing mass fractions of 30, 10, and 20% glass-fiber-reinforced resin waste, respectively. It was found that the maximum amount of recyclate that could be added to a composite board was 30% of weight. Beyond these percentages, the materials blend became unmanageable and the mixture less amenable to impregnation with fiber. Presented studies indicated that comminuted glass-fiber-reinforced resin waste-filled polypropylene composites are promising candidates for structural applications where high stiffness and fracture resistance are required.