Search

Information on boiling point (BP) is a crucial metric for defining petroleum streams. Understanding the BP distribution range of hydrocarbon products is crucial for selecting an appropriate way to process feedstocks, controlling the process, identifying impurities, and developing new tests. To evaluate BP range rapidly, the refinery employs simulated distillation (SimDis) by gas chromatography (GC) paired with a flame ionization detector (FID) and a capillary column. This method is used to examine the level of contamination in petroleum products. Jet A-1 fuel is an essential product whose specifications can be altered by diesel contamination. Some producers utilize the same distribution line for both products, contaminating the Jet fuel that is shipped. We conducted research to determine the lowest level of diesel contamination in jet A-1 fuel. The study consists of varying proportions of diesel (0.5%, 2%, and 5% mass) blended with jet A-1 to determine the impact on standard specifications DEF STAN 91-91/12 and ASTM D1655. Among those methods, SimDis by GC-FID was the most successful method for identifying a little level of diesel contamination. Properties of jet fuel, such as thermal stability, water separation, and electrical conductivity, are particularly sensitive to trace contamination and can be altered by it. [ABSTRACT FROM AUTHOR]

Key Takeaways: As the hazards of per‐ and polyfluoroalkyl substances—widely known as PFAS—are better understood, regulations and guidelines for addressing them will continue to evolve. Water utilities play a significant role in PFAS mitigation by incorporating detection, monitoring, and treatment techniques into their operations. Many methods for PFAS analysis are in place. A detailed explanation and comparison of each can help utilities determine the best approaches for their particular circumstances. [ABSTRACT FROM AUTHOR]

Copyright of Romanian Journal of Family Medicine / Revista Română de Medicina Familiei is the property of Media DOM Express 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.)

The inclusion of quantitative nuclear magnetic resonance (qNMR) spectroscopy in industry has historically been stifled by a lack of accessibility, caused in‐part by the large costs of traditional high‐field spectrometers, the maintenance required for these, and the expertise necessary to manage and use them. In recent years, the emergence of benchtop NMR technology, an accessible, affordable, and automatable alternative, has led to a more feasible incorporation of NMR into quality control spaces, an area traditionally reserved for other techniques such as gas chromatography and liquid chromatography, which are routinely combined with detection techniques such as mass spectrometry. While these techniques are commonly used in analyzer‐type applications using gold standard methods of analysis, wherein an instrument is dedicated to performing specific assays, this remains uncommon for NMR. Herein, we perform a full method verification using benchtop qNMR on a population of benchtop NMR instruments according to the ASTM designation E691–22, a standard used to determine the precision of a test method. To our knowledge, this is the first published example of this type of study for benchtop NMR spectroscopy. For this work, a total of five analysts performed assays on 23 different benchtop NMR instruments for the analysis of hydroxypropyl betadex according to the USP–NF method, and the results are compared using a variety of statistical methods. The results of this work demonstrate that benchtop NMR technology is effective and robust under repeatability and reproducibility conditions and is a powerful tool for these types of routine quality control analyses. [ABSTRACT FROM AUTHOR]

Highlights: What are the main findings? The removal of caustic impurities by means of an ion exchange resin can be attractive as it does not use water as a rinse in the final bioturbosine washes. Ultrasonic radiation used as an energy source in the transesterification reaction can help to reduce production times; What is the implication of the main finding? Bio-jet fuel from biomass can replace a portion of jet fuel; Jet fuel production is a key element in the aviation industry's strategy to reduce operating costs and environmental impacts. Alternatives are required, and bioturbosine obtained from biomass can replace significant amounts of jet fuel. In this investigation, the properties of the production of bioturbosine from coconut oil and mixtures of B5, B10, B20, B1OO, bottom, and jet fuel were measured according to the ASTM standards. A transesterification reaction between coconut oil and methanol was carried out using ultrasound, resulting in 99.93% conversion of triglycerides into bioturbosine at room temperature for 10 min, with a 6:1 molar ratio of methanol and oil. The catalyst concentration was 1.0 g/100 g of oil, and purification was carried out without water using an ion-exchange resin to remove impurities. The results obtained for density and viscosity were within the regulations. The temperature of the clogging point for a cold filter in the mixtures was up to −30 °C. The average caloric values of mixtures B5, B10, and B20 were 45,042, 44,546, and 43,611 MJ/Kg, respectively. In a copper corrosion test, the result for all samples was class 1A. It is expected that the results of this research may influence the use of bioturbosine in the aviation industry. [ABSTRACT FROM AUTHOR]

The development of the use of natural fiber as a constituent material for FFP as an external concrete retrofit that is environmentally friendly and affordable price has been quite developed. One plant that grows massively in Indonesia and can be extracted into fiber is water hyacinth. This plant will be extracted into fiber through three variations, namely mechanical, boiling, and natural alkali, by using bio-resin to produce WHBR (Water Hyacinth and Bio-Resin) FRP in the form of rope and weave. The tensile behavior of the obtained WHBR FRP will be investigated against ASTM A931-18 and ASTM D3039 requirements. The results of the investigation are compliance with failure criteria, the impact of the tensile test result on compliance with failure criteria, and the impact of pattern-delignification on tensile strength performance. In this study, it has been found that the boiling treatment-plain woven variation of WHBR FRP has the best properties and it is recommended as an external concrete retrofit material for future studies. [ABSTRACT FROM AUTHOR]

Copyright of Structural Integrity & Life / Integritet i vek Konstrukcija is the property of University of Belgrade, Faculty of Mechanical Engineering 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.)

The radial strength of balloon expandable stents represents a key property for a successful recanalization of sclerotic blood vessels. This study focuses on the most commonly used method for investigation of radial strength and radial stiffness via segmented head test setup. A custom made user software was used for evaluation of the radial force curves considering requirements of international standards such as ASTM F3067. Contributing factors during measurement such as friction and test setup deformation as well as the single cycle and multi cycle approach were addressed and discussed.

Bio-diesel has proven to be a better alternative to fossil diesel due to its eco-friendly, ease of production, high cetane rating and sustainability (renewable) which are the major drawback of fossil fuel. In this study, a non-edible avocado seed oil was used to formulate biodiesel. The avocado seed oil was extracted using cold press mill. The seed oil was then subjected to esterification to reduce the acidic value to <1mgKOH/g using sulphuric acid catalyst (H2SO4). Subsequently, the optimisation of the transesterification process was carried out by investigating the effect of different blend of molarity of oil to methanol (1: 6, 1.5:6, 2: 5, and 2.5:4.5) concentration of KOH catalyst % weight (0.5, 1, 1.5 and 2), reaction time in minutes (55, 65, 75, and 85) and reaction temperature (55,60,65 and 70) °C on the yield of ASO biodiesel (%). The study revealed that highest ASO biodiesel yield (%) was observed with KOH 1% weight concentration; 75 min reaction time, 650C and 1: 6 molarity of oil to methanol. The physicochemical parameters of ASO biodiesel assessed were in conformity with ASTM standard and with literature. The assessment revealed that ASO biodiesel has some improved properties over fossil diesel. Therefore, it can be used solely or as a blend in diesel engine. [ABSTRACT FROM AUTHOR]

Editor's Note: This is a response to "Why a Workplace Barrier Face Covering is a Bad Idea" by Mark Nicas. DOI: 10.1177/10482911231193771 A commentary mischaracterizes the paper "Barrier Face Coverings for Workers." The American Society for Testing and Materials (ASTM) Barrier Face Covering (BFC) F3502-21 standard established performance criteria for face coverings as source control. While the standard states that BFCs may offer some personal protection, this was never its primary goal. We described a proposal for BFCs to be worn in low-risk (nonhealth care) workplaces for the purpose of source control, not respiratory protection. We did not recommend BFCs as respiratory protection for any worker in any workplace. A BFC is not "another term for a cloth mask"; many higher performing products are based on nonwoven high-efficiency filter media. Our "time to infectious dose" table was included to illustrate the impact of different degrees of inward and outward leakage, not to describe a dose-response relationship, which includes time and airborne particle concentration. [ABSTRACT FROM AUTHOR]

SARS-CoV-2 is primarily a respiratory virus that can potentially be transmitted through fomites. Sodium hypochlorite (NaOCl) and peracetic acid (PAA) are widely used disinfectants on surfaces in diverse settings such as hospitals and food production facilities. The objectives of this study were to investigate the virucidal efficacy of NaOCl and PAA against SARS-CoV-2 using the ASTM standard methods. In the suspension assay, NaOCl and PAA (5, 50, and 200 ppm) were tested against SARS-CoV-2 in the presence/absence of soil load after 1 min of contact time. In the carrier assay, NaOCl and PAA were tested at 200, 400, 600, and 1,000 ppm for 1 min and 200 and 1,000 ppm for 5 and 10 min. Stainless steel (SS) and high-density polyethylene (HDPE) disks were used as carriers. The virus was suspended in soil load and the disinfectants were prepared in 300 ppm of hard water. Virus quantification was done by TCID50 assay using Vero-E6 cell line. NaOCl and PAA were effective (> 3 log reduction in infectious virus) at 50 ppm in the absence of soil load. However, in the presence of soil load, 200 ppm was required for > 3 log reduction in virus infectivity. In contrast, NaOCl and PAA at 200 ppm and with a 1-min contact time were not effective against SARS-CoV-2 on either SS or HDPE surfaces. PAA at 200 ppm for 10 min was effective against SARS-CoV-2 on SS and HDPE surfaces, whereas NaOCl required 1,000 ppm for 10 min to be effective against SARS-CoV-2 on both surfaces. [ABSTRACT FROM AUTHOR]

In the modern world, energy and fuels are of utmost importance. Rapid characterization of petroleum and other hydrocarbon‐based fuel is a well‐researched field. Gas chromatography has traditionally been used to separate the different species and characterize the chemical content in fuels. Ideally, every molecule would be separated and characterized, but due to the complexity of the petroleum matrix, many compounds coelute. With the help of different detectors, more information can be gained, but there does not exist a single detector that can unambiguously differentiate and identify every compound. Vacuum ultraviolet spectroscopy (VUV) is a relatively new detector that can alleviate many limitations of other detectors. Based on spectroscopic absorption, VUV detection can provide qualitative and quantitative information regarding the composition of different fuels. It also provides certain advantages, allowing the deconvolution of coeluting peaks and differentiation between constitutional isomers. VUV has been used to classify the range of chemical components in many diverse fuel samples. Here, the contributions of VUV detection to petrochemical analysis to date are reviewed. [ABSTRACT FROM AUTHOR]

Jet fuel production is a key element in the aviation industry’s strategy to reduce operating costs and environmental impacts. Alternatives are required, and bioturbosine obtained from biomass can replace significant amounts of jet fuel. In this investigation, the properties of the production of bioturbosine from coconut oil and mixtures of B5, B10, B20, B1OO, bottom, and jet fuel were measured according to the ASTM standards. A transesterification reaction between coconut oil and methanol was carried out using ultrasound, resulting in 99.93% conversion of triglycerides into bioturbosine at room temperature for 10 min, with a 6:1 molar ratio of methanol and oil. The catalyst concentration was 1.0 g/100 g of oil, and purification was carried out without water using an ion-exchange resin to remove impurities. The results obtained for density and viscosity were within the regulations. The temperature of the clogging point for a cold filter in the mixtures was up to −30 °C. The average caloric values of mixtures B5, B10, and B20 were 45,042, 44,546, and 43,611 MJ/Kg, respectively. In a copper corrosion test, the result for all samples was class 1A. It is expected that the results of this research may influence the use of bioturbosine in the aviation industry.

Fourier transform infrared (FTIR) spectroscopy is a well-established primary qualitative screening tool for Condition Monitoring (CM) of in-service lubricants, with three key determinative ASTM methods often used to accept their continued use or condemn them. These include Acid Number (AN), Base Number (BN) and moisture (H2O), all tedious and environmentally problematic titrimetric methods. The latter have been developed into FTIR quantitative methods through the use of targeted stoichiometric reactions to produce infrared-active products readily and accurately quantified. FTIR CM is discussed in the context of these methods, their tribological significance and the basic analytical concepts examined and compared. The evolution of new FTIR qualitative and quantitative methodology is reviewed from its origins in edible oil analysis to the high-throughput analytical FTIR systems used by commercial CM laboratories to produce ASTM-comparable data in lieu of titration. Comparisons of chemometric vs. stoichiometric approaches are made, including implementation, applications, and instrumentation. Commercial implementation and performance of proprietary quantitative FTIR/IR systems are discussed with a focus on the stoichiometric approach. Current developments include generic, manual FTIR methods combining simplicity, universality, and practical environmental benefits in being able to serve as alternatives to titrimetric procedures. A new methodological approach that could unify the three deterministic FTIR methods under a single, IR-active reaction product is also presented.

The choice of ASTM D638 versus ASTM D3039 test specimen shape is usually based on the perceived susceptibility of ASTM D638 test specimens to failure within the fillet radius. For test results to be accepted, specimens should fall inside the narrow length (i.e., ASTM D638) or outside of the grips (i.e., ASTM D3039), according to ASTM polymer and plastic tensile test standards. The choice of ASTM test specimen shape has received little published research, particularly for plastic FRP materials. Through a comparison of the mechanical performance and failure acceptance rates of test specimen geometries manufactured using plastic straw waste FRP, ASTM D3039, and ASTM D638 test specimens, this study offers evidence-based guidance to offer recommendations for using current ASTM polymer testing standards for plastic FRP. According to the results, using ASTM D3039 instead of specimens from ASTM D638 has inherent advantages. Due to the rectangular shape of the test specimen, ASTM D3039 test specimens consistently fall within the gauge length of the test specimen. According to the results, there will be variations in the tensile test results depending on the different cross-sectional areas of the test specimen geometries, just like with traditionally manufactured polymer composites. [ABSTRACT FROM AUTHOR]

Asthma is a chronic inflammatory airway disease, with an increasing prevalence in children, up to 10-15%. This is a presentation of a clinical case of a 7-year-old boy which helps us understand more easily the clinical manifestations, particularly in young children, how to diagnose asthma at this age, and the case management difficulties. The presentation of hereditary factors and of the asthma trigers, the clinical manifestations and the investigations we can use and recommend to support our diagnosis help us to understand the patient with bronchial asthma and to establish the monitoring plan. The correct treatment of asthma in children leads to the disappearance of symptoms in adulthood and to the avoidance of future complications. [ABSTRACT FROM AUTHOR]

Asthma is the most common chronic noncommunicable disease, having a complex determinism. Early exposure to various environmental factors such as caesarean delivery, use of antibiotics during the neonatal period and formula fed in the first months of life are all associated with an increase in the prevalence of asthma. Also, the intestinal and lung microbiota can have an impact on the association with asthma through changes in the immunomodulatory cells, in the composition of microbiota, but also through changes in the metabolites of the intestinal microflora. The gut microbiome also impacts systemic immunity. There is also evidence which suggests that changes in gut microbiota may play a role in obesityrelated asthma. [ABSTRACT FROM AUTHOR]

In this article we propose a model of recommendation of experimental protocols based on the user's context of use. As a case study, 107 experiments related to 5 experimental protocols of the soil mechanics laboratory tests of the Civil Engineering in the ASTM (American Society for Testing and Materials) standards are analyzed. Starting from the formal specification of the experimental protocol, a representation model is proposed. This model allows to describe the entities that converge in this scientific product, contributing to the formalization of the experimental protocol in a domain of knowledge that has been little explored from this perspective. With the previous result, a recommendation model is presented. This model takes advantage of the concept of the context of use to highlight within the experimental protocol, the entities that characterize the context in which a user performs a new experiment, reproduces, repeats or audits previously performed experiments. This also contributes to considering the recommendation of this type of products that is not yet visible in the repositories of experimental protocols explored in this research. With two previous models, a software prototype is built and using test cases, the representation model and the recommendation model are validated with satisfactory results in a content-based strategy to achieve a recommendation to the user. [ABSTRACT FROM AUTHOR]

This work presents the experimental and finite element (FE) simulations to investigate the behavior of both unstiffened and anisogrid composite cylindrical shells subjected to low‐velocity axial impact. Impact damage has been an epidemic problem for composite structures. Even subjected to a low‐velocity impact, thin‐walled composite structures may sacrifice its load‐carrying capacity considerably due to various modes of failure. A low cost, reliable and innovative manufacturing process is proposed for the production of anisogrid cylindrical lattice structures. Initially, test coupons are fabricated as per American Society for Testing of Materials (ASTM) standards and inspected using infrared (IR) thermography to find the imperfections incurred during fabrication. The test coupons without defects were only taken into account for material characterization. FE simulations were carried out on both the unstiffened and anisogrid shells using LS‐DYNA® for a series of low‐velocity impacts. Also these shell structures were subjected to impact loading experimentally for the validation of the numerical results. The results of these studies indicate that the anisogrid model presented in this work possesses a great load‐carrying capacity than an unstiffened shell under dynamic loading conditions, also the weight of the structure has been reduced up to 51.27%. Numerical simulation results are in good agreement with the experimental data, having less than 11.56% of maximum deviation on the energy absorption value. [ABSTRACT FROM AUTHOR]

Background Context: Cage subsidence remains a serious complication after spinal fusion surgery. Novel porous designs in the cage body or endplate offer attractive options to improve subsidence and osseointegration performance.Purpose: To elucidate the relative contribution of a porous design in each of the two major domains (body and endplates) to cage stiffness and subsidence performance, using standardized mechanical testing methods, and to analyze the fusion progression via an established ovine interbody fusion model to support the mechanical testing findings.Study Design/setting: A comparative preclinical study using standardized mechanical testing and established animal model.Methods: To isolate the subsidence performance contributed by each porous cage design feature, namely the stress-optimized body lattice (vs. a solid body) and microporous endplates (vs. smooth endplates), four groups of cages (two-by-two combination of these two features) were tested in: (1) static axial compression of the cage (per ASTM F2077) and (2) static subsidence (per ASTM F2267). To evaluate the progression of fusion, titanium cages were created with a microporous endplate and internal lattice architecture analogous to commercial implants used in subsidence testing and implanted in an endplate-sparing, ovine intervertebral body fusion model.Results: The cage stiffness was reduced by 16.7% by the porous body lattice, and by 16.6% by the microporous endplates. The porous titanium cage with both porous features showed the lowest stiffness with a value of 40.4±0.3 kN/mm (Mean±SEM) and a block stiffness of 1976.8±27.4 N/mm for subsidence. The body lattice showed no significant impact on the block stiffness (1.4% reduction), while the microporous endplates decreased the block stiffness significantly by 24.9% (p<.0001). All segments implanted with porous titanium cages were deemed rigidly fused by manual palpation, except one at 12 weeks, consistent with robotic ROM testing and radiographic and histologic observations. A reduction in ROM was noted from 12 to 26 weeks (4.1±1.6° to 2.2±1.4° in lateral bending, p<.05; 2.1±0.6° to 1.5±0.3° in axial rotation, p<.05); and 3.3±1.6° to 1.9±1.2° in flexion extension, p=.07). Bone in the available void improved with time in the central aperture (54±35% to 83±13%, p<.05) and porous cage structure (19±26% to 37±21%, p=.15).Conclusions: Body lattice and microporous endplates features can effectively reduce the cage stiffness, therefore reducing the risk of stress shielding and promoting early fusion. While body lattice showed no impact on block stiffness and the microporous endplates reduced the block stiffness, a titanium cage with microporous endplates and internal lattice supported bone ingrowth and segmental mechanical stability as early as 12 weeks in ovine interbody fusion.Clinical Significance: Porous titanium cage architecture can offer an attractive solution to increase the available space for bone ingrowth and bridging to support successful spinal fusion while mitigating risks of increased subsidence. [ABSTRACT FROM AUTHOR]

Asthma is the most common chronic lung disorder and affects approximately 15-20% of the population in developed countries, whereas the rate is around 2-4% in less developed countries. The incidence rates are much higher in children, with roughly 40% of children reporting having a wheezing episode which can turn at some point into asthma. Understanding pathogenesis can help to better treat those patients. The release of these inflammatory mediators is the primary cause of the key feature of asthma – chronic airway inflammation. This in turn leads to the airway remodeling phenomenon, which is seen by the thickened airway walls and hence the narrowing of the air passages, ultimately having a profound impact on the course and chronicity of the condition. [ABSTRACT FROM AUTHOR]

Foreign metallographic standards are updated every 2–5 years and include an image analyzer, which was used for the first time more than 20 years ago. All valid modern standards are based on quantitative metallography methods, since visual estimation using the rating charts method contrary to direct stereological measurement by means of an image analyzer cannot provide unity of measurements. The status of State Standard GOST 1778–70 has been analyzed; until now, it is used in the revision of 1970, and high-priority problems of its improvement are formulated with allowance for the world experience of development of standard practice for determining the nonmetallic inclusions in steel. Herewith, the use of an automatic image analyzer should be available for all estimation methods described in State Standard GOST 1778–70 together with the visual estimation by methods Sh and manual measurements using methods K, P, and L. The practice of direct stereological measurements of the volume fraction, size, number, shape, and distribution of nonmetallic inclusions in steel should become one of the methods of State Standard GOST 1778. The names of rating charts (OT (DO = dot oxides), SN (NDS = non-deformable silicates), SKh (BS = brittle silicates), etc.) should be considered conditional, since optical metallography cannot estimate the chemical composition of the complex multiphase deoxidation products retained in the finished metal after secondary steelmaking. Interlaboratory round-robin tests, which are required for objective assessment during acceptance tests performed by the manufacturers and consumers of metal products, should become regular practice for provision of measurements unity. [ABSTRACT FROM AUTHOR]

Addition of oxygenated additives with gasoline is one of the recent methods to enhance the properties of gasoline and further improve performance of the engines. N-Butanol and Di Isopropyl Ether (DIPE) are having favorable fuel properties and these can be blended with gasoline. In this paper the properties oxygen, density, volatility, octane number and calorific value of the blends obtained from experimental study are discussed in detailed. Oxygenates N-Butanol and DIPE are blended with gasoline individually in a ratio of 10, 20 and 30%vol and named as N10, N20, N30, D10, D20 and D30 respectively. The properties of gasoline-oxygenates blends shows, the use of blends will enhance the combustion process in the engine. Compared to N-Butanol blends, DIPE blends produced higher calorific value and octane number. DIPE shows better gasoline blending properties and it may be used as an oxygenate in petroleum refineries. [ABSTRACT FROM AUTHOR]

Anxiety is a comorbidity among patients with chronic respiratory diseases such as asthma, COPD and COPD-asthma. Anxiety disorders in this population have a considerable influence on asthma management, because they influence the perception of symptoms, and anxiety related to treatment can influence compliance. Patient noncompliance with treatment for chronic respiratory diseases compromises the success of treatment and the patient's quality of life, while increasing medical costs. Therefore, the aim of our study was to provide patientcentered care and determine which dimension of anxiety is associated with asthma, COPD and COPD-asthma in the general population after controlling age, background and sex. In order to obtain information on the response to treatment, questionnaires on symptom control (Asthma Control Test (ACT), COPD Assessment Test (CAT)) and asses anxiety using the ASQ questionnaire. The result obtained indicates that no compliant person presented a high score of the dimensions of anxiety (somatic, behavioral and cognitive dimension.) and predominates a low overall score. The symptoms associated with anxiety have a low, medium overall score but also a high score on the first visit. The first and second age categories have a low score in both the behavioral and somatic dimensions. In the age category 3 and 4 are people with low score and medium score behavioral dimension and cognitive dimension. In conclusion we can say that through repetitive control we obtained increased treatment compliance was achieved, leading to improved lung function, symptoms control and therefore reduced anxiety in the case of patients with asthma, COPD and COPD-asthma. [ABSTRACT FROM AUTHOR]

În decembrie 2019, OMS a identificat un nou coronavirus care a dus la un sindrom de detresă respiratorie acută severă (SARS-CoV-2). COVID-19, boala produsă de noul coronavirus, pare să afecteze mai puțin copiii și să fie mai puțin severă ca la adult, fiind asociată cu o rată de fatalitate redusă. Astmul și fibroza chistică (FC) sunt cele mai frecvente boli cronice care afectează copiii și adolescenții. Nu este bine stabilit dacă există un risc crescut de evoluție nefavorabilă datorată infecției cu SARS-CoV-2. Cercetări care au demonstrat că receptorul angiotensinei 2 (ACE2) necesar pentru recunoașterea coronavirusului și infectarea cu acesta ar putea fi mai puțin exprimate în căile aeriene ale copiilor atopici au condus către un paradox care situează astmul ca fiind o afecțiune protectoare pentru COVID-19. Pacienții cu FC manifestă disfuncție citokinică și inflamaţie cronică menținută de diversitatea de patogeni din căile respiratorii, mecanisme care se suprapun cu cele fiziopatologice din COVID-19. Date internaționale sugerează că un număr foarte restrâns de pacienți cu FC au avut simptome și complicații datorate COVID-19 şi, dacă boala este mai ușoară decât s-a anticipat în cazul FC, aceasta ar putea fi ca urmare a unei protecții rezultate din efectul celular al mutațiilor CFTR asociate cu procesarea virală. Luate împreună, astmul și fibroza chistică, boli cronice cu impact semnificativ asupra morbidității și mortalității la copil și la adult, pot constitui un model de factori care ar putea reduce impactul SARS-CoV-2, ceea ce creează oportunități pentru cercetări ulterioare.

Globally, energy crisis focusses on the researchers to explore innovative and alternative sources of energy. This tribulation has acute for the developing countries. Generation of any kind of waste is a vital problem for the environment. Some wastes have the characteristics of producing energy by different thermochemical conversions. Inaugurate of using plastics has curtailed many problems in our daily life. Waste plastics are assessed as harmful things when it is thrown into the landfill because of their non-degradable property. Plastic waste is becoming a tremendous threat to the environment as a little fraction of it is being recycled through plastic re-production. Rest of them are thrown into the landfill or incinerated. To get rid of the environmental problem and to recover fuel, municipal waste plastics were converted into a liquid hydrocarbon by using catalyst at a temperature range of 250–400°C. Aluminium oxide (Al2O3) and zinc oxide (ZnO) were used as a catalyst in this study. The maximum conversion was found 78 ± 2% when the catalyst percentage was 5%. Fuel quality was tested using ASTM standard method and compared with other commercial-grade gasoline and diesel oil. The density and kinematic viscosity of the oil were found as 779 kg/m3 and 2.693 cSt. Research Octane number (RON) of produced oil was 84. Physical properties such that flash points, pour point and cetane index of produced oil were also measured and found as 20°C, less than 3 and 65.5, respectively. The properties of produced oil were much closer to that of diesel oil. It could be concluded that plastic waste may be a potential source of alternative fuels.

Additive manufacturing processes and products are very present in the current productive landscape, and in fact these technologies have been one of the most intensively studied and improved during the last years; however, there is still no defined and homogeneous regulatory context for this field. In this work, a thorough review of the main general and specific regulatory developments in design, materials and processes standards for additive manufacturing has been carried out, with special attention to the standards for mechanical characterization of polymer-based products. In many cases standards developed for other productive contexts are identified as recommended references, and some contradictory trends can be identified when different documents and previous experiences are consulted. Thus, as it is logical considering that all these technologies are involved in an intensive and continuous evolution process, there is a certain lack of clarity regarding the standards to be considered. This work aims to contribute to clarify the current standardization context in additive manufacturing and provide some guidelines for the identification of appropriate standards. The paper also emphasizes that the key for next regulatory developments in mechanical testing is to develop standards that consider particular AM processes along with materials. Moreover, a great gap between available standard about additive technologies based on metallic materials and polymer materials during the last years has been detected. Finally, the provided overview is considered of interest as support for research and practice in additive manufacturing, and both in intensive productive scenarios and for particular users and makers.

In Nepal, the formation of seven provinces has been seen as a driving force in promoting the development of civil engineering structures in remote parts of the nation. Although aimed to promote the livelihoods of people residing in such areas, if aforesaid activities are unplanned and unsustainable they lead to a backlash in the health of the community and the surrounding environment. In our study, bridges in Barjugad, Guigad, Dhangadhi, Kapadi Nadi, Patharaiya, and Thado Khola are taken as references. Some of these bridges are close to the Khaptad National Park. Likewise, the Makarigad Hydropower project is also cited, and the effects of the recommendation made are reviewed. Various American Society for Testing and Materials(ASTM), Indian Standard(IS) codes are validated, and the Environmental Impact Assessment(EIA) is made. The consequences of the boring, field test, groundwater table monitoring, and liquefaction are assessed. Case studies from around the world have also been stated and their health effect over several domains is presented. Potential risks to the health of construction workers based on etiological agents are mentioned, out of which occupational lung diseases are taken further into account. An example of dams and hydropower plants has been taken to explore the long-lasting effects of construction on the health of local residents. Airborne dust, a major hazard, has been identified and described to understand its pathogenicity. An epidemiological triangle, for occupational lung diseases, has been used as a simple model for disease causation. Similarly, four levels of prevention to control dust-related diseases in construction workers have been mentioned. In conclusion, our paper highlights the possible consequences of construction works and also suggests some precautionary measures to mitigate the same.

Background: During Coronavirus disease 2019 pandemic, the general public used any face-worn products they could get to overcome the shortage of N95 respirators and surgical masks. These products, often not meeting any standards, raised concerns about their effectiveness in reducing the spread of respiratory viruses., Methods: This study quantified total outward leakage (TOL) of units from 9 face-worn product categories used by members of the general public. A benchtop system was devised to test 2 units from each category on 2 different-sized headforms with silicone elastomer skin. Each unit was donned 5 times per headform., Results: Both face-worn product category and headform size significantly affected TOL (P value < .05). The TOL of tested face-worn products varied from 10% to 58% depending on both model and headform size. Face-worn products donned on the medium headform had a higher mean TOL compared to those donned on the larger headform., Conclusions: Overall, single-layer cloth masks are the least effective measure for source control due to their highest TOL among the tested face-worn products. Three-layer disposable face masks may be a favorable option for source control among the public. A standard should be developed for face-worn product design and manufacturing to accommodate different facial sizes., (Published by Elsevier Inc.)

Statistically derived allowables are representative for the behavior of a composite material system in a given structural context where data variability needs to be contemplated. In particular, they define the strength of the material as characterized by various coupon tests according to ASTM standard procedure subjected to the actual manufacturing process and layup stacking sequences. The current paper presents a detailed comparison between virtual allowables predictions obtained using MSC Digimat and the experimentally determined values of a certified material backed up by a 3x2x3 (batch/panel/specimen) stochastic approach. Tests generate the required data for building material model ab initio of carbon fibers reinforced epoxide resin in form of 2x2 twill woven fabric used for qualifying an innovative composite wing for the Next Generation Tilt Rotor (NGCTR). Numerical models of in-plane tension, compression and shear test methods have been assembled along with an associated material model allowing numerical predictions to be validated with the coupon level experimental results as final purpose. Standard statistical model has been adopted in order to include material and manufacturing process variabilities to define B-basis allowables. The calibrated statistical FEM method performed for different layup configurations have been used to fully characterize the mechanical behavior of the analyzed CFRP material and to predict performances for thicker laminates. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic that we are still going through continues to bring challenges in the management of many chronic diseases that change their evolutionary course or is the source of pathologies for which not enough information has yet been accumulated for a common diagnostic and therapeutic denominator, in adults and especially in children. Although most children who had SARS-CoV-2 infection had mild to moderate manifestations, there were also cases with severe forms that frequently associated a chronic pathology with little or no therapeutic control. The authors present the case of a patient diagnosed with noncompliant therapeutic asthma, who after a SARS-CoV-2 infection presented spontaneous pneumothorax, a life threatening complication that required emergency surgery. [ABSTRACT FROM AUTHOR]

During the COVID-19 pandemic, American Society for Testing and Materials level 3 and level 2 medical face masks (MFMs) have been used for most health care workers and even for the first responders owing to a shortage of N95 respirators. However, the MFMs lack effective peripheral seal, leading to concerns about their adequacy to block aerosol exposure for proper protection. The purpose of this study was to evaluate the peripheral seal of level 3 and level 2 MFMs with a 3-dimensional (3D-) printed custom frame. Level 3 and level 2 MFMs were tested on 10 participants with and without a 3D-printed custom frame; the efficiency of mask peripheral seal was determined by means of quantitative fit testing using a PortaCount Fit Tester based on ambient aerosol condensation nuclei counter protocol. The 3D-printed custom frame significantly improved the peripheral seal of both level 3 and level 2 MFMs compared with the masks alone (P <.001). In addition, both level 3 and level 2 MFMs with the 3D-printed custom frame met the quantitative fit testing standard specified for N95 respirators. The 3D-printed custom frame over level 3 and level 2 MFMs can offer enhanced peripheral reduction of aerosols when using collapsible masks. With the shortage of N95 respirators, using the 3D-printed custom frame over a level 3 or level 2 MFM is considered a practical alternative to dental professionals. [ABSTRACT FROM AUTHOR]

Astmul este o afecţiune heterogenă caracterizată prin inflamaţia cronică a căilor aeriene. Colesterolul este un factor proinflamator corelat, ȋn unele studii cu inflamaţia din astm. În Spitalul Clinic de Copii „Dr. Victor Gomoiu“, ȋn perioada ianuarie 2016-septembrie 2018, a fost initiat un studiu prospectiv care a inclus 100 de copii ȋn vȃrstă de 5-18 ani, diagnosticaţi cu astm alergic și sensibilizare aeroalergenică. Toţi pacienţii ȋnrolaţi au fost monitorizaţi privind nivelul colesterolului, treapta terapeuticǎ primită şi gradul de control al astmului. Obiectivul studiului a fost să se evalueze dacă există o asociere între valorile colesterolului seric și controlul astmului și între colesterolul seric și treapta de tratament de control (ca indicator al severităţii astmului). Concluzii. În lotul studiat, pacienţii ȋncadraţi ȋn categoriile de astm parţial controlat și necontrolat au fost ȋn procent mai mare cu valori crescute ale colesterolului seric comparativ cu cei cu astm controlat; copiii ȋnregistraţi ȋn categoriile de astm moderat și sever au fost ȋn procent mai mare cu colesterol seric total crescut faţă de cei cu astm uşor.