Avaliação de meios para armazenagem de resíduos de amálgama de prata

The purpose of this study was to evaluate the shown efectiveness by different ways of storage of amalgam residues, to reduce the liberation of mercury from such residues to the air ambience and to compare with lhe highest value established by the NR-15 (regulation norm number 15) from the decroe number 3214, of the brazilian labor ministry, dated from june, 8 h of 1978. As mercury source, amalgam in capsules of the brand Dispersalloy (Dentsplay) was used after grinding, in the mechanic amalgamizer varimix II (caulk), the quantity of amalgam in cach capsule was collected from a sieve that had a mesh with mm of width to standardize lhe fragmentation. The fragmented amalgam was stored in jars made of transparent polypropylene, that could store 5()() ml; one of the jars was kept in a dry atmosphere (group l), and the others were immersed in distilled water (group 2), in glycerin (group 3) and in a solution of dentistry x-ray fixer (group 4). These jars were kept tightly shut, and put inside a bigger polypropylene recipient, during the time they were stored. Thirty minutes after the storage of the fragments, the jars were opened and air samples were collected around each of the four jars. The same procedure was performed 30 days after the initial storage. A Pump Sampler of Air manufactured by SKCâ was used to do the air collection. The air samples were analyzed by a spectrophotorneter of atomic absorption, to determinate the quantity of mercury. This analysis showed the following mercury concentration rates in the air samples, from the first and the second collection of the four groups, in the following order: group I 6,100 mg/m3 and 0,816 mg/m3 ; group 2 - 0,252 mg/rn3 and 0,157 mg/m 3 ; group 3 — 0,071 mg/m3 and 0,005 mg/m3 ; groui) 4 — 0,256 mg/m3 and 0,005 mg/m3. The results showed that glycerin is the safest way to store amalgam residues, since the quantity of mercuor vapor found in the air, in both collections: the first one and the other 30 days after, never surpassed the highest value established by NR-15 (Regulation Norm number 15), also demonstrating, bigger security, since the initial period of storage of these residues.

Arugula and pre-converted arugula extract as natural Nitrate/Nitrite sources for heat-treated sausages

The aim of this study was to investigate using arugula or pre-converted extracts as nitrite alternatives in heat-treated fermented sausages. Sausages with nitrite, 150 mg/kg of NaNO2, 1.2% arugula extract, and 1.5% pre-converted arugula extract were formulated. Natural nitrate sources added resulted in significantly lower oxidation content compared to negative control groups at initial storage. The addition of natural nitrate sources influenced colour, pigments, and conversion rate of sausages. Pre-converted arugula extract showed little effect on the residual nitrite content. The result of colour, oxidation, and nitrite analysis suggest pre-converted arugula is a potential nitrite replacer, but arugula as a nitrate source is limited to provide the functions of nitrite.

Comparison between two generalized Nash models with a same non-zero initial condition

Initial condition can impact the forecast precision especially in a real-time forecasting stage. The discrete linear cascade model (DLCM) and the generalized Nash model (GNM), though expressed in different ways, are both the generalization of the Nash cascade model considering the initial condition. This paper investigates the relationship and difference between DLCM and GNM both mathematically and experimentally. Mathematically, the main difference lies in the way to estimate the initial storage state. In the DLCM, the initial state is estimated and not unique, while that in the GNM is observed and unique. Hence, the GNM is the exact solution of the Nash cascade model, while the DLCM is an approximate solution and it can be transformed to the GNM when the initial storage state is calculated by the approach suggested in the GNM. As a discrete solution, the DLCM can be directly applied to the practical discrete streamflow data system. However, the numerical calculation approach such as the finite difference method is often used to make the GNM practically applicable. At last, a test example obtained by the solution of the Saint-Venant equations is used to illustrate this difference. The results show that the GNM provides a unique solution while the DLCM has multiple solutions, whose forecast precision depends upon the estimate accuracy of the current state.

Evaluation of Irrigation Safety by Operation Management of Water Supply from Large Scale Agricultural Reservoirs

Due to recent climate change, droughts occur frequently, thereby causing a shortage of agricultural water. However, supplies to most agricultural reservoirs have been designed assuming that droughts occur at a frequency of 10 years. Therefore, continuous drought has led to low storage rates. Thus, in this study, a water balance analysis was performed on the Naju reservoir, and the changes in the water shortage according to the minimum storage rate restriction management to cope with drought were evaluated. As a result, a higher management storage rate level results in a higher initial storage rate in the next year, thereby decreasing the annual average shortage. In addition, it shows that a decrease in the frequency of drought and its intensity can be reduced according to the minimum storage management during wet years.

SISTEM PENGEPAKAN DENGAN METODE SORTASI PENGATURAN KECEPATAN KONVEYOR BERDASARKAN UKURAN KEMASAN MENGGUNAKAN OUTSEAL PLC NANO V.4 DAN HAIWELL SCADA

The production process which is designed is a packaging system for the initial storage of products to be filled in the packaging, in this study a conveyor is designed that can sort objects using a proximity sensor and adjust the speed based on the size of the packaging using pulse width modulation (PWM), and can fill the packaging based on the size of the packaging. The product. Automatic control of packing using Outseal PLC Nano.V.4, the system can be controlled and monitored using Haiwell SCADA software on a PC. Outseal PLC nano V.4 test results can operate based on program commands that have been designed. The use of PWM Outseal PLC Nano V.4 on a 12 volt DC motor as a speed controller works in accordance with the duty cycle and PWM scale values given with an efficiency value of 86,56 % at at a PWM value of 900 and 86,23 % at a PWM value of 1023. HMI system made using Haiwell SCADA to control and monitor a successful packing system. Outseal PLC Nano V.4 can operate optimally with the SCADA system. The overall system test results of all sensor components, product packaging and HMI variables are 100 % successful, with an average processing time of packing size M for 11.62 seconds and size L for 14.58 seconds.

Health risk assessment of heavy metals (Cu, Zn, and Mn) in wild oat grown in soils amended with sediment dredged from the Joumine Dam in Bizerte, Tunisia

The Joumine Dam located in northern Tunisia has lost more than 20% of its initial storage capacity due to sedimentation, meaning that sediment management is necessary. The sediments at the reservoir bottom act as a sink for nutrients and chemicals originating from the upper agricultural lands and take the form of suspended particles. We proposed that the dredged sediments could be used to amend arid to semiarid soils, as this would partially cover the financial burden of dredging works and reduce the volume of these deposits. However, to check the feasibility of using the sediments as a fertilizer, it was necessary to assess the potential health risks from contaminants in the sediments. Therefore, the present study aimed to evaluate the human health risk (i.e., the hazard quotient, HQ) from heavy metals consumed due to the ingestion of Bromus ramosus (wild oat) grown in soil amended with the Joumine Dam sediments. Plant growth was monitored in macrocosm (amendment rate of 1.17%) and microcosm (amendment rate ≤ 10%) bioassays to elucidate the metal concentrations in roots, stems, leaves, and seeds. Zn, Cu, and Mn concentrations were analyzed in the plants grown in the macrocosm experiments, while the follow-up was only performed for Zn in the plants grown in the microcosm experiments. The human exposure to soil pollutants (HESP) evaluation model was adopted to evaluate the health risk (HQ) to humans through direct and indirect oral exposure to heavy metals in wild oat. At the macrocosm scale, Cu was found to be the main source of risk (HQ = 1.86) to children. At the microcosm scale, utilization of the sediment reduced the mobility and bioavailability of copper in the soil, thus decreasing the potential health risk from this metal. Graphic abstract

Effect of interfacial modification on the thermo-mechanical properties of flax reinforced polylactide stereocomplex composites

The flax and equivalent proportion of poly(L-lactic acid)/poly(d-lactic acid) (PLLA/PDLA) were melt compounded and injection molded to prepare flax reinforced polylactide stereocomplex (sc-PLA) bio-composite, and two different coupling agents, hexamethylene diisocyanate (HMDI) and maleic anhydride grafted polypropylene (MAPP), were used to modify the interface of composite, then the influence of different interfacial modification on the structure and properties of composite was investigated. The results showed HMDI modification decreased the total crystallinity of composite but promoted the formation of stereocomplex crystallites (sc), whereas MAPP modification could improve both the total crystallinity and sc crystallinity. HMDI modification significantly improved the interfacial compatibility of composite, and thereby effectively improved the tensile strength and initial storage modulus of composite. By contrast, the interfacial compatibility of flax/sc-PLA composite was weakened by MAPP modification. Although the tensile properties of flax/sc-PLA/MAPP composite decreased, the impact strength of composite was increased by 12.1% than the unmodified composite. Therefore, the tailored flax/sc-PLA composite with varying properties could be prepared by different interfacial modification.

Rapid evidence summary on SARS-CoV-2 survivorship and disinfection, and a reusable PPE protocol using a double-hit process

ABSTRACTIn the COVID-19 pandemic caused by SARS-CoV-2, hospitals are stretched beyond capacity. There are widespread reports of dwindling supplies of personal protective equipment (PPE), which are paramount to protect frontline medical/nursing staff and to minimize further spread of the virus. We carried out a rapid review to summarize the existing evidence on SARS-CoV-2 survivorship and methods to disinfect PPE gear, particularly N95 filtering facepiece respirators (FFR). In the absence of data on SARS-CoV-2, we focused on the sister virus SARS-CoV-1. We propose a two-step disinfection process, which is conservative in the absence of robust evidence on SARS-CoV-2. This disinfection protocol is based on an initial storage of PPE for ≥4 days, followed by ultraviolet light (UVC), dry heat treatment, or chemical disinfection. Importantly, each of the two steps is based on independent disinfection mechanisms, so that our proposed protocol is a multiplicative system, maximising the efficacy of our disinfection process. This method could be rapidly implemented in other healthcare settings, while testing of each method is undertaken, increasing the frontline supply of PPE, and avoiding many of the upstream issues of supply chain disruption currently being faced.