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Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) 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.)

Abstract Background Classic vitrification methods are not appropriate when there are minimal numbers of viable sperm, and the new methods emphasize the low semen volumes in these cases. The aim was to assess the efficacy of the cryotech as a device for freezing low sperm volume, through the two methods of open (OVS) and closed (CVS) vitrification systems. Methods Testicular biopsy samples from 30 men with obstructive azoospermia (OA) were assigned to three groups fresh control (FC), OVS, and CVS. Testicular sperms were selected using an ICSI injection pipette and vitrified on the cryotech straws, containing one droplet of freezing medium. After warming, sperm head morphometric characterizations were evaluated with the MSOME technique. Sperm motility, membrane integrity, chromatin quality assessment including DNA fragmentation, Chromomycine A3 staining (CMA3), and Aniline Blue (AB) were assessed. Fluorescein isothiocyanate-conjugated Pisum sativum agglutinin (FITC-PSA) was done to examine sperm acrosome integrity. Results The mean sperm motility, viability, and sperm with intact acrosome reduced after vitrification, in both methods of CVS, and OVS, but the results were more promising in the closed method (p

Bu çalışmada üzüm posası hem inert hem de oksijenli atmosferlerde karbonizasyon davranışının incelenmesi amaçlanmıştır. Herhangi bir biyokütlenin torrefaksiyon koşullarında oluşturacağı ürünlerin miktarı, öncelikle biyokütlenin temel bileşenlerine bağlıdır. Çünkü temel bileşenlerin yapısal farklılıkları termal davranışlarının da farklı olmasına neden olmaktadır. Bu yüzden meydana gelen değişimlerin ve ortaya çıkan ürünlerin anlaşılması açısından şüphesiz oldukça önemlidir. Lignoselülozik maddelerin yapısında yaklaşık olarak %80 uçucu bileşen ve %20 sabit karbon bulundu. Karbonizasyon prosesi boyunca biyokütlenin elementsel oksijen oranı sıcaklıkla önemli oranda azaldı. 200-350˚C aralığında uçucu bileşenlerin bir kısmı biyokütleden ayrıldı ve böylece biyokütlenin yapısı daha sert ve kırılgan bir hale geldi. Büyük oranda hemiselülozların bozunması ve daha az oranda selüloz moleküllerinin bozunması suretiyle orijinal biyokütlenin fiber yapısı parçalandı. Bu durum biyokütle yapısının daha kırılgan bir hale gelmesine ve daha kolay öğütülmesine yardımcı olmaktadır. Uçucu bileşenler uzaklaştırıldıktan sonra biyokütlenin elementsel oksijen oranı azaldı ve buna bağlı olarak ısı değeri kademeli olarak 19 MJ. kg-1 den 21- 23 MJ. kg-1 değerine yükseldi.

NASA's Perseverance and ESA's Rosalind Franklin rovers have the scientific goal of searching for evidence of ancient life on Mars. Geochemical biosignatures that form because of microbe-mineral interactions could play a key role in achieving this, as they can be preserved for millions of years on Earth, and the same could be true for Mars. Previous laboratory experiments have explored the formation of biosignatures under closed systems, but these do not represent the open systems that are found in natural martian environments, such as channels and lakes. In this study, we have conducted environmental simulation experiments using a global regolith simulant (OUCM-1), a thermochemically modelled groundwater, and an anaerobic microbial community to explore the formation of geochemical biosignatures within plausible open and closed systems on Mars. This initial investigation showed differences in the diversity of the microbial community developed after 28 days. In an open-system simulation (flow-through experiment), the acetogenic Acetobacterium (49% relative abundance) and the sulfate reducer Desulfosporomusa (43% relative abundance) were the dominant genera. Whereas in the batch experiment, the sulfate reducers Desulfovibrio, Desulfomicrobium, and Desulfuromonas (95% relative abundance in total) were dominant. We also found evidence of enhanced mineral dissolution within the flow-through experiment, but there was little evidence of secondary deposits in the presence of biota. In contrast, SiO2 and Fe deposits formed within the batch experiment with biota but not under abiotic conditions. The results from these initial experiments indicate that different geochemical biosignatures can be generated between open and closed systems, and therefore, biosignature formation in open systems warrants further investigation. [ABSTRACT FROM AUTHOR]

This study aimed to compare the impact of CAD/CAM closed systems and open systems on the marginal gap of monolithic zirconia-reinforced lithium silicate (ZLS) ceramic crowns, as both systems are used in everyday dentistry, both chair-side and laboratory. For the closed system, 20 plastic teeth were scanned by a Primescan intra-oral scanner (IOS), and for the open system, the same number of plastic teeth were scanned by Trios 4 IOS. For the closed system, CEREC software was used, and for the open system, EXOCAD software was used. All 40 ZLS crowns were grinded by the same four-axis machine and cemented with Temp-bond, followed by self-adhesive resin cement. For each type of cement, an evaluation of the marginal gap was conducted by scanning electron microscopy (SEM). Before comparisons between the groups, a Kolmogorov–Smirnov test was performed on the study variables showing a normal distribution (p > 0.05). Independent T tests (α = 0.05) and paired-sample T tests (α = 0.05) were used. The independent T test found no significant mean marginal gap differences in the zirconia-reinforced lithium silicate crowns bonded with Temp-bond and scanned by Primescan (28.09 μm ± 3.06) compared to Trios 4 (28.94 μm ± 3.30) (p = 0.401), and there was no significant mean marginal gap differences in zirconia-reinforced lithium silicate crowns bonded with self-adhesive resin cement (Gcem ONE) and scanned by Primescan (46.70 μm ± 3.80) compared to Trios 4 (47.79 μm ± 2.59) (p = 0.295). Paired-sample T tests showed significantly higher mean marginal gaps with Gcem ONE compared to Temp-bond for the total mean marginal gap when scanning with Primescan (p = 0.0005) or Trios 4 (p = 0.0005). In everyday dentistry, both closed systems (Primescan with Cerec) and open systems (Trios 4 with Exocad) can be used to achieve an acceptable (<120 µm) marginal gap for ZLS CELTRA® DUO single crowns. There is a significant difference between cementation with Temp-bond and Gcem ONE self-adhesive resin cement (p < 0.05). [ABSTRACT FROM AUTHOR]

This study has proposed that organic matter transfer and transformation into and through a peatland is dominated by preferential loss of carbohydrates and the retention of lignin-like molecules. Here we used elemental analysis and thermogravimetric analysis to analyse the biomass, litter, peat soil profile, particulate organic matter, and dissolved organic matter fluxes sampled from a continental raised bog in comparison a maritime blanket bog. The macromolecular composition and thermodynamic analysis showed that in the raised bog there had been little or no transformation of the organic matter and the accumulation was rapid with comparatively little transformation with only 13% loss of cellulose by 1 m depth compared to 92% removal of cellulosic material in the blanket bog. The lack of transformation is reflected in a difference in long term carbon accumulation rates between raised and blanket bog sites. We propose that raised bogs, with their lack of a stream outfall, have high stable water tables that mean the pore water become thermodynamically closed and reactions cease higher in the peat profile than in a blanket bog where sloping sites mean a frequent flushing of pore water and discharge of water leading to fluctuating water tables, flushing of reaction products and pore spaces remaining open. [ABSTRACT FROM AUTHOR]

Diurnal freeze–thaw process occurs in the Lianghekou area in winter, which will affect the construction progress and quality of the project. In this paper, the compressibility of clay experiencing the freeze–thaw (F-T) cycles under different impacting factors was investigated. A series of unidirectional F-T tests were carried out in a closed system, and the compressibility tests were carried out for the same specimens underwent F-T cycles to study the compressibility along the specimen height. The experimental results demonstrate that the initial moisture content of specimens, the cooling temperature, and the number of F-T cycles affect the compressibility of specimens. As the cooling temperature decreases, the initial moisture content or the number of F-T cycles increases, the compressive strain of the affected zone of specimens increases under the same vertical pressure, while the confined compressive modulus decreases. The variation of the compressibility for the unaffected zone is different from that for the affected zone. For the same impacting factor, the compressive strain of the affected zone is greater than that of the unaffected zone, while the confined compressive modulus of the former is less than that of the latter. The change of compressibility is mainly affected by the characteristics of cryostructure and moisture migration of the specimen after F-T. This research may provide some guidance for the engineering construction process in winter in the seasonally frozen ground region. [ABSTRACT FROM AUTHOR]

This paper describes the design, operation and test results of a simple microprocessor-based device for measuring slow liquid flows. The device uses a module of 30 digital optical sensors to track the movement of a single air bubble inserted into a tube of flowing liquid. During a measurement session, the air bubble remains within the sensor module at all times, allowing the instrument to take measurements for any length of time. The liquid whose flow rate is being measured moves only in the closed tube system, without contact with other components of the device. The test of the device itself was carried out using a tube with an inner diameter of less than 1 mm, where the device is capable of measuring flow rates on the order of microliters per minute. Tests of the device showed good agreement between the measured volumetric flow rate and the reference flow rates of the infusion pump over the entire measurement range. The advantages and limitations of the device are discussed, as well as the prospects for developing the method. [ABSTRACT FROM AUTHOR]

The primary aim of this systematic analysis is to highlight opportunities to improve the environmental impact of advanced therapy medicinal products (ATMP) manufacturing. We have compared the Greenhouse Gas (GHG) emissions expressed in CO2eq of a classic clean room open system (AinB) Cell Factory versus a comparable closed system equipped with isolators (AinD). We have therefore outlined a theoretical situation to simulate the use of a closed system with an equivalent production output to that obtained in the Cell Factory (CF) of the Regina Margherita Children's Hospital. Open and closed systems for ATMPs have been compared as regards energy requirements, ecological footprints, and costs by analyzing a hypothetic cell production cycle of 21 days. The results demonstrate energy saving and a reduction of 52% in GHG emissions using closed systems per process cycle. Moreover, a reduction in production costs in an isolator setting is also evident. This study shows that the closed system solution has evident advantages compared with the open one. [ABSTRACT FROM AUTHOR]

Background and Objectives: A fully closed system solution to manufacture serum eye drops using diluted serum has remained elusive, necessitating production steps to mitigate bacterial contamination risks in a clean suite environment, hampering production efficiency amid growing demand. We describe our recent implementation of a fully closed manufacturing process at New Zealand Blood Service. Materials and Methods: A dockable format for sterile saline manufactured to custom specifications configured with a 15‐cm tubing to enable sterile connections was sourced from a local pharmaceutical manufacturer. Results: From a total of 30,168 eye drop vials manufactured since implementation, the average production time was reduced by up to 45% performed in the general laboratory environment, attributed to eliminating processes performed in a clean suite. No bacterial contamination was observed, demonstrating robust sterile connections. Conclusion: Dockable saline takes serum eye drops manufactured from a functionally closed system to a fully closed system, thereby enhancing patient safety, significantly reducing manufacturing time and cost and transforming production from a highly restrictive process into a portable workflow that is simple, practical and effective. [ABSTRACT FROM AUTHOR]

Energy, cost, and environmental concerns play a vital role in understanding governing parameters of distributor design in falling film evaporators. Distributor design is a hidden parameter in many experimental papers. The uniform distribution of liquid refrigerant over the tube bundle mostly depends on two‐phase liquid refrigerant and vapor refrigerant. This work conducted experiments with two distribution systems with and without separation of liquid‐vapor refrigerant after expansion valve for the same evaporator capacity with R134a as a refrigerant. Results reveal that; separating vapor refrigerant has a positive impact on the approach of the evaporator with an open system distributor arrangement. The highest delta T and lowest practice are found at a heat flux of 13.97 kW/m2 with an available system distributor compared to a closed system with a heat flux of 14.25 kW/m2. The open system arrangement in the distributor is the novel parameter for distributor design, ensuring uniform distribution with minimum pressure drop and dry suction. An open system distributor has an average 16.1% capacity increase over a closed system. The experimental analysis helps to understand different parameters for the design of distributors in falling film evaporators for uniform distribution. [ABSTRACT FROM AUTHOR]

Background: Manufacturing methods for dimethyl sulfoxide (DMSO)‐cryopreserved platelets (CPPs) are manual and labor intensive. Thawing and prepare‐for‐transfusion steps are in an open system that requires transfusion within 4 h. A fill‐and‐finish system (CUE) can automate the manufacturing process. A newly configured bag system allows freezing, thawing, and use of resuspension solutions while maintaining the functionally closed system, and extending the post‐thaw shelf life beyond 4 h. Our objective is to evaluate the feasibility of the CUE system and the functionally closed bag system. Study design and Methods: DMSO was volumetrically added to double‐dose apheresis platelets, concentrated, and delivered to a 50‐ or 500‐mL ethylene‐vinyl acetate (EVA) bag by the CUE (n = 12). The functionally closed bag system contained 25 mL platelet additive solution 3 (PAS‐3) in a 50‐mL EVA bag. Control CPP (n = 2) were manually prepared. PAS‐3 and CPP were thawed together. CPP were stored up to 98 h (20–24°C) and tested using a standard assay panel. Results: CUE prepared CPP met the design targets: volume, platelet content, and DMSO concentration. CUE CPP P‐selectin was high. CD42b, phosphatidylserine (PS) expression, and live cell percentage were favorable compared to controls and favorably maintained over storage. The thrombin generation potency was slightly reduced compared to controls. The 50 mL EVA bag maintained pH for up to 30 h, and the 500 mL EVA bag beyond 76 h. Discussion: The CUE system presents a technically feasible method to prepare CPP. A functionally closed bag system with resuspension solution was successful and can extend the post‐thaw storage time of CPP. [ABSTRACT FROM AUTHOR]

This study aimed to compare the impact of CAD/CAM closed systems and open systems on the marginal gap of monolithic zirconia-reinforced lithium silicate (ZLS) ceramic crowns, as both systems are used in everyday dentistry, both chair-side and laboratory. For the closed system, 20 plastic teeth were scanned by a Primescan intra-oral scanner (IOS), and for the open system, the same number of plastic teeth were scanned by Trios 4 IOS. For the closed system, CEREC software was used, and for the open system, EXOCAD software was used. All 40 ZLS crowns were grinded by the same four-axis machine and cemented with Temp-bond, followed by self-adhesive resin cement. For each type of cement, an evaluation of the marginal gap was conducted by scanning electron microscopy (SEM). Before comparisons between the groups, a Kolmogorov–Smirnov test was performed on the study variables showing a normal distribution (p > 0.05). Independent T tests (α = 0.05) and paired-sample T tests (α = 0.05) were used. The independent T test found no significant mean marginal gap differences in the zirconia-reinforced lithium silicate crowns bonded with Temp-bond and scanned by Primescan (28.09 μm ± 3.06) compared to Trios 4 (28.94 μm ± 3.30) (p = 0.401), and there was no significant mean marginal gap differences in zirconia-reinforced lithium silicate crowns bonded with self-adhesive resin cement (Gcem ONE) and scanned by Primescan (46.70 μm ± 3.80) compared to Trios 4 (47.79 μm ± 2.59) (p = 0.295). Paired-sample T tests showed significantly higher mean marginal gaps with Gcem ONE compared to Temp-bond for the total mean marginal gap when scanning with Primescan (p = 0.0005) or Trios 4 (p = 0.0005). In everyday dentistry, both closed systems (Primescan with Cerec) and open systems (Trios 4 with Exocad) can be used to achieve an acceptable (® DUO single crowns. There is a significant difference between cementation with Temp-bond and Gcem ONE self-adhesive resin cement (p < 0.05).

To better predict the timely variation of algal blooms and other vital factors for safer drinking water production, a new AI scanning–focusing process was investigated for improving the simulation and prediction of algae counts. With a feedforward neural network (FNN) as a base, nerve cell numbers in the hidden layer and the permutation and combination of factors, etc., were fully scanned to select the best models and highly correlated factors. All the factors involved in the modeling and selection included the date (year/month/day), sensor data (temperature, pH, conductivity, turbidity, UV254-dissolved organic matter, etc.), lab measurements (algae concentration) and calculated CO2 concentration. The new AI scanning–focusing process resulted in the best models with the most suitable key factors, which are named closed systems. In this case study, models with highest prediction performance are the (1) date–algae–temperature–pH (DATH) and (2) date–algae–temperature–CO2 (DATC) systems. After the model selection process, the best models from both DATH and DATC were used to compare the other two methods in the modeling simulation process: the simple traditional neural network method (SP), where only date and target factor as inputs, and a blind AI training process (BP), which considers all available factors as inputs. Validation results show that all methods except BP had comparable results for algae prediction and other water quality factors, such as temperature, pH and CO2, among which DATC displayed an obviously poorer performance through curve fitting with original CO2 data compared to that of SP. Therefore, DATH and SP were selected for the application test, where DATH outperformed SP due to the uncompromised performance after a long training period. Our AI scanning–focusing process and model selection showed the potential for improving water quality prediction by identifying the most suitable factors. This provides a new method to be considered in the enhancing of numerical prediction for the factors in water quality prediction and broader environment-related areas. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Shenyang Agricultural University is the property of Journal of Shenyang Agricultural University Editorial Department 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.)

Industrial robots are widely used in the painting industry, such as automobile manufacturing and solid wood furniture industry. An important problem is how to improve the efficiency of robot programming, especially in the current furniture industry with multiple products, small batches and increasingly high demand for customization. In this work, we propose an outer loop adaptive control scheme, which allow users to realize the practical application of the zero-moment lead-through teaching method based on dynamic model without opening the inner torque control interface of robots. In order to accurately estimate the influence of joint friction, a friction model is established based on static, Coulomb and viscous friction characteristics, and the Sigmoid function is used to represent the transition between motion states. An identification method is used to quickly identify the dynamic parameters of the robot. The joint position/speed command of the robot's inner joint servo loop is dynamically generated based on the user-designed adaptive control law. In addition, the zero-moment lead-through teaching scheme based on the dynamic model is applied to a spray-painting robot with closed control system. In order to verify our method, CMA GR630ST is used to conduct experiments. We identified the parameters of the dynamic model and carried out the zero-moment lead-through teaching experiment to track the target trajectory. The results show that the proposed method can realize the application of modern control methods in industrial robot with closed control systems, and achieve a preliminary exploration to improve the application scenarios of spray-painting robots. [ABSTRACT FROM AUTHOR]

Sago grows in lowland and peat swamp regions that are relatively isolated due to limited basic infrastructures, including energy supply, especially electricity. These limitations constraining the development of sago starch production and industry. The sago starch production process generates by-products such as sago bark waste, pith waste, and wastewater which are potentially used as an energy source. This paper discusses a closed system model of an energy-independent sago starch production process from the utilization of by-products and wastewater. A mass balance model was developed to calculate the energy potency of by-products and waste to construct a closed system for the sago starch production process. The model's output showed that the by-product from processing 1,000 tons of sago stems per day with an optimal yield of 14% potentially generates 90,562 kWh of energy. This energy potency can meet the 26,070 kWh energy needed for sago starch production, making it possible to develop into a closed production system. Further research is needed to determine the site-specific aspects that affect energy sufficiency.

Technologies of communication condition human sense-making. They do so by creating the social environment we inhabit and extending their structural biases and logics through human use. As such, this essay inquires into the prevailing habits of mind in the digital era. Employing a media ecology of communication, I argue that digital computers and microprocessors are defined by three structural properties and, hence, underlying logics: digitization (binary code), algorithmic execution (input/output), and efficiency (machine logic). Repeated exposure to these logics cultivates a digital mind, a model of thinking, communicating, and sense-making characterized by intransigence, impertinence, and impulsivity. I conclude the essay by exploring the broader implications of a digital mind, paying particular attention to the challenges it poses to democratic politics. [ABSTRACT FROM AUTHOR]

The research on the experimental growth of Oreochromis aureus at different photoperiods in a closed system was carried out in Trujillo, Peru at the Aquaculture Laboratory of the Universidad Nacional Trujillo. The seed was obtained from the La Balsa Module and the experimental growth of O. aureus was evaluated with three photoperiod treatments T1-24: 0, T2-12: 12, and T3- natural photoperiod in an indoor closed system. The growth in length and the average weight of the tilapia was 106,28 mm and 23,18 g in T1, in T2 102,69 mm and 21,55 g, and T3 102,69 mm and 21,55 g in 128 days of aging. It is concluded that the growth of O. aureus was slightly higher in the photoperiod of T1-24: 0 without presenting significant differences in the treatments. [ABSTRACT FROM AUTHOR]

This paper presents mechanical properties and biological durability properties against soft-rot (soil bed test) and subterranean termites (grave-yard test) of the wood modified with a vinylic derivative of glycerol or polyglycerol and maleic anhydride at different curing conditions. Wood modification was performed through impregnation of European beech (Fagus sylvatica) with an aqueous solution of polyglycerol maleate, glycerol maleate, or maleic anhydride at 10 or 20% w/w concentration, followed with curing under oven heating (OHT) in an open system (120°C, 150°C, or 220°C) or under heat pressurised steam (HPS) at 150°C in a closed system. Results revealed that almost all modified wood presented higher modulus of elasticity (MOE) values than untreated wood, however, modulus of rupture (MOR) and work to maximum load in bending (WMLB) decreased considerably. Biological durability in the soil bed test against soft-rot indicated that almost all modified wood was specified as "durable" to "very durable". However, among the treatments, the wood modified with polyglycerol maleate/glycerol maleate/maleic anhydride at 20% under OHT 150°C or the wood modified at lower additive concentration (10%) under OHT 220°C presented excellent durability against subterranean termites within a period of 328 days in the field. [ABSTRACT FROM AUTHOR]

The conversion from natural ecosystems to intensive agriculture can promote different changes due to constant fertilization. Fertilizations provoke high dependency on nutrient inputs and produce changes in nutrient dynamics, microbial activity, and the composition of soil microbial communities. However, few studies evaluate the high dependency on nutrient inputs with biogeochemical, and enzymatic variables and link the results with nutrient stoichiometry analyses to understand the effect on nutrients availability, microbial activity and biogeochemical cycling. The aim of this work was to analyse the effect of agricultural land use and fertilization with organic and inorganic P on soil nutrient dynamics (C, N and P) in Andosols. We divided the article into three sections, the first one that identifies the effect of land use change on biogeochemical, enzymatic activities, and ecological stoichiometry variables and identifies the dominant processes in each plot to answer: does the sites work as open or closed systems in terms of nutrient exchange and energy? The second section uses the results obtained in section one in order to identify the stability of the biogeochemical variables individually due to the change in land use, calculates resistance and resilience indices, and finally, the third section, covers an incubation experiment on soils from an agricultural site and a pine-oak site, which were fertilized with organic and inorganic compounds with the same concentration of P. At the end of this experiment, the changes in microbial activity and biogeochemical and ecological stoichiometric variables, such as threshold element ratio (TER) were identified, contributing with our data to increase the knowledge about the effects of the changes in soil elemental stoichiometry associated to fertilization, on resistance and resilience of soil organic matter transformation, soil nutrients availability and enzymes synthesis. With the variables analysed in these sections we aim to answer the following questions: will organic agriculture modify the stability of soil nutrient transformation, organic nutrient stores and activity of enzymes that degrade organic matter? and, what effects will fertilization have on the enzymatic activities linked to phosphorus? Our results suggest that the availability of PO 4 3− and NO 3 − are the variables that explain most of the variance that affects the nutrient dynamics in the agricultural plot, concluding that this site depends on nutrient inputs and acts as an open system. We identified that most of the variables are highly resistant; however, the nitrification process shows high vulnerability (less resistance, lower than 0.5) and is affected by the change in land use. In the final section, we found that both types of fertilization (inorganic and organic) negatively affected the activity of the β-glucosidase (BG) enzyme (0.068 μmolPNP g−1 h−1 for the control versus 0.010 and 0.007 μmolPNP g−1 h−1 for each fertilization respectively in the agricultural site). We identified N limitation induced by organic fertilization (Log e DOC:DON = 3.61 ± 0.4, Log e TER C: N = 0.6 ± 0.85; p = 0.02) and C limitation due to inorganic fertilization (Log e DOC:DOP = 2.66 ± 0.5, Log e TER C: P = 3.7 ± 1.3; p = 0.02). In conclusion, our results showed that the change in land use and organic and inorganic fertilizations with P modify processes related not only to P but also to C and N dynamics with changes in microbial activity. This study shows how land use change modify soil nutrients and energy flows in the ecosystem, quantified the vulnerability of soil microbial processes and provides information about the relevance of knowing the nutrient stoichiometry of fertilizer before to be applied. [ABSTRACT FROM AUTHOR]

Objective: This article is aimed to explore the influence of closed/open conditions on the flavor compounds of Maillard reaction. Methods: The species and amounts of flavor compounds produced from Tyrosine-based Maillard reactions under closed/open conditions in different solvents and reaction temperatures were determined by GC-MS. Results: The results showed that the species and contents of flavor products are quite different under closed and open conditions. The amounts of alcohol flavor compounds were higher in closed system, while the amount of esters and ketones were higher inopensystem. Conclusion: The amounts of active oxygen and intermediates produced during the reactions likely result in the difference between closed and opensystems from the proposed mechanisms.

The hydrocarbon generation of Jurassic crude oil and kerogen samples from Sichuan Basin was simulated under two different linear heating procedures of 20°C/h and 2°C/h in a confined closed system (sealed gold tubular-autoclave-system). The experimental data was recorded in detail during the experiment. The hydrocarbon generation behavior of crude oil and kerogen was described based on the gaseous hydrocarbon component data obtained in the experiment, and the similarities and differences in hydrocarbon generation evolution were analyzed. The results show that the hydrocarbon generation process of different source rocks can be divided into three parts. The hydrocarbon generation range of kerogen is wider, the hydrocarbon generation range of crude oil cracking gas is more concentrated, and the main gas generation stage of crude oil is later than that of kerogen. Through the comparative analysis of hydrocarbon generation process of crude oil and kerogen, this paper aims to deepen the understanding of hydrocarbon generation of crude oil and kerogen under the condition of deep burial and hope to provide reference for the study of gas accumulation in over-mature areas. [ABSTRACT FROM AUTHOR]

ABSTRACT We assessed the effect of stocking density on physiological parameters (blood lactate, glucose, cortisol, hematocrit), water quality (temperature, dissolved oxygen, pH, unionized ammonia, carbon dioxide), and survival during the transportation of fingerling (24.5 ± 4.7 g) and juvenile (615.8 ± 122.2 g) pirarucu (Arapaima gigas) for six hours in plastic bags. The tested densities were 65, 80, 95, 110 and 125 g L-1 for fingerlings, and 50, 80, 110, 140 and 170 g L-1 for juveniles (three replicates each). Parameters were measured prior to and immediately after transportation, and at 24 and 96 hours recovery after transportation. No mortality was observed, except for fingerlings (< 3%) at densities of 110 and 125 g L-1 during recovery. All the water quality parameters were significantly altered after the transportation of fingerlings and juveniles. Water temperature, dissolved oxygen, carbon dioxide and unionized ammonia increased, but pH decreased. Only carbon dioxide and unionized ammonia differed among densities. Cortisol levels did not increase over time, except for the juveniles at 170 g L-1, which still had high cortisol after 96 hours. Glucose significantly increased after transportation for all the treatments and returned to the initial values during the recovery period. Conversely, the lactate values were still high after 96 hours. Hematocrit was assessed only for juveniles and was significantly lower after transportation. We conclude that fingerling and juvenile pirarucu can be safely transported at densities up to 95 g L-1 and 140 g L-1, respectively.

Abstract Environmental DNA metabarcoding has been widely touted as a powerful tool for monitoring biodiversity in marine ecosystems. However, this method still requires thorough validation and standardization before it can be widely applied for ecological monitoring. The potential utility of environmental DNA metabarcoding is greatest in systems with high levels of diversity, yet environmental DNA metabarcoding has typically been validated in closed systems with relatively low levels of diversity. Additionally, the use of a multiple marker approach has been minimally explored under controlled, closed systems in the literature. Using a pilot study, we assess the ability of eDNA metabarcoding to capture biodiversity in a highly diverse closed system at the Ripley's Aquarium of Canada in Toronto, Ontario. Our pilot study highlights several key knowledge gaps that must be addressed before metabarcoding can be employed for widespread use in ecological monitoring. We found that environmental DNA metabarcoding recovered just over 50% of target species and 80% of target genera within a closed marine system containing 107 species and 44 genera using previously published markers for COI, 12S, and 16S. Additionally, COI and 12S were found to identify fewer target species than 16S, with COI generating the most off‐target identifications, but maximum detection success was achievable by combining all three markers. We discuss numerous key limitations which currently present barriers to the application of eDNA metabarcoding for studying highly diverse marine systems. These include marker selection, data validation and confidence, and the complexity of abundant and diverse novel systems. This study highlights important, yet incompletely resolved, challenges of environmental DNA metabarcoding for the detection of marine fishes in a diverse closed system environment using a multiple marker approach.

Many studies on Li-O2 batteries have addressed the chemical and morphological evolution of the device as a function of electrode material, electrolyte, and discharge current density. Here we report that simple operating conditions can also affect discharge product formation. Results show the formation of Li2O2 and LiOH in experiments using continuous O2 flow (open system) and without it (closed system), and an additional more complex chemistry including LiOOH•H2O, Li2O and LiO2 in the closed system. This unexpected difference was also examined during charging of the Li-O2 cell, in which the LiOOH•H2O is preferably reversed in comparison to LiOH. Beside the influence in the reaction routes, the O2 flow and pressure impact on the cell performance. The total discharge capacity varies from 1,459 mA g − 1 to 2,460 mA g − 1 decreasing the O2 flow. In contrast, when using the closed pressurized system, the discharge capacity increased up to 5,851 mA g − 1 with the same electrode in the best result, as the electrolyte loss due to evaporation was avoided.

Sterile fluid transfer between vessels is a key step in cell therapy manufacturing and requires specialised devices to maintain sterility of both vessels before, during and after the transfer. This review introduces two main types of devices for sterile fluid transfer in cell therapy manufacturing, namely single-use sterile connectors and tube welders. While these are excellent devices for infrequent moderate to large volume transfers, a new multiple-use aseptic connector may fill the gap for frequent small volume fluid transfers that are particularly important for autologous cell therapy manufacturing.

African countries, like other countries of the world, possess knowledge systems that are indigenous to them, which are believed by many to have the potential for development. Besides having a coordinated outlet for transferring such knowledge, some claim that Africa is the origin of knowledge or the foundational ideas that rule the world scientifically and technologically. This claim, however, seems to be contradicted by the manifest poor scientific and technological state of African countries. Unravelling the reason(s) for this disconnect, therefore, forms part of the broader aims of this study. In this study, we examine African indigenous knowledge systems in the light of the current scientific and technological development. It is found that, unlike their Western counterparts that operate an open system, African indigenous knowledge systems have some occultic accretions that restrict access to them and preclude their custodians from publicly teaching and demonstrating their underlying principles for the consumption of the public. Relying on the nature and structure of the Egyptian Mystery Temple reputed for being a symbol of knowledge and wisdom in Africa, we argue that owing to their lack of a trial-and-error mechanism that underpins scientific and technological knowledge and development, African indigenous knowledge systems stifle scientific and technological development rather than encourage it. [ABSTRACT FROM AUTHOR]

Water stream flow is the major factor that affects the performance of a spiral solar water collector, it can be maximize the collector performance by decreasing the water stream flow velocity. The water stream flow was in two spiral tube arrangements of length 15 m, diameter 0.012 m, and number of coils (11). The inner surface of the solar collector was coated with matte black paint with a mixture of nanomaterial (thermal dye with 5% TiN). The experimental rig placed in Babylon - Iraq, at longitude (44.4 E) and latitude (32.4 N) in the best experimental conditions for the province during the month's (2,3,4,5). Also, a simulation program was made to extract the results in the case of a single flow, where the geometry was drawn in the Solid Work program and then entered into the ANSYS program, where the same practical cases were applied. The experimental results were compared with the numerical results which gave a good agreement with an error percent of 11% and 8.8% in the closed and opened system, respectively. The experiment included two parts, the first part: the flow of water in four different levels at case of the closed system (1, 1.5, and 2) L/min. The second part: the flow of water was at the same levels but at case of open system. The results showed that a decrease in the mass flow rate leads to increase in exit temperature and thus increase in the temperature difference between (inlet and outlet). The maximum temperature difference in the closed system was 25.2°C for a water flow rate of 1 L/min. The maximum temperature difference in the open system was 12.3°C for the water flow rate of 1 L/min. [ABSTRACT FROM AUTHOR]

Important tasks in the field of improving the quality of concrete and reinforced concrete products, increasing the level and pace of industrial development put serious demands on enterprises in terms of improving technical and economic performance, as well as a clearer and more efficient system of electrical equipment and energy saving. In this regard, the issues of efficient operation of existing equipment and improvement of its technological characteristics become especially important. On the other hand, improving and accelerating the process of construction production, raising it to a new level is possible only with high productivity and reliability of the relevant technological lines. With the growing international requirements for the quality of production processes, there is a need to increase and stabilize it. To do this, currently used high-performance building complexes with the required level of quality of technological operations, which must be interconnected both in terms of productivity and reliability of the element base. Based on this, the presence of a weak mechanism (parts), more often than others fails and thus reducing the reliability of the entire line, is unacceptable in such a set of operations. As a result, measures aimed at ensuring the reliability of the elements of mechanical equipment of technological lines for the production of building materials and products are crucial in this matter. In addition, the issue of regulating the productivity of technological processes or their individual operations becomes important at this stage of development. Such regulation can reduce electricity consumption, improve system reliability and ensure efficient operation of the electric drive with the production mechanism. The dynamic and static modes of operation of the electric drive of the gravitational concrete mixer were investigated, the system of the electric drive of the frequency converter - asynchronous, as a basic variant for the studied object was considered. Modeling of the calculated system is performed and dynamic characteristics are constructed. The stability and quality of the system by frequency criteria are evaluated. [ABSTRACT FROM AUTHOR]

The article considers poverty as a socio-cultural phenomenon through the concept of «poverty culture». Selected concepts of structural poverty, persistent poverty, the underclass or the lower class. The characteristic features and peculiarities of the subculture of poverty are marked. It is determined that the main aspect of poverty culture is inheritance of poverty on the basis of negative norms and values.

Background: This study compared the marginal gap (MG) and absolute marginal discrepancy (AMD) of computer-aided design and computer-aided manufacturing (CAD–CAM) used in open systems (OSs) and closed systems (CSs) for producing monolithic zirconia-reinforced lithium silicate (ZLS) ceramic crowns. Methods: 60 ZLS ceramic crowns were cemented to abutment acrylic teeth; thirty crowns were designed and milled by an OS, and thirty by a CS. All crowns were sectioned for evaluating the marginal gap by scanning electronic microscopy (SEM). To compare the marginal gap between CS and OS techniques, data were analyzed using the independent-samples Mann–Whitney U Test (α = 0.05). Results: AMD was found to be significantly better for the closed system (p < 0.05). Mean AMD values for the CS were 148 µm, and for the OS it was 196 µm. MG was found to be significantly better for the OS (p < 0.05). Mean MG values for the CS were 55 µm, and for the OS they were 38 µm. Conclusions: The marginal gap in relation to AMD was significantly better for CS. However, the marginal gap in relation to MG was significantly better for OS. Both techniques showed clinically acceptable MG values (<120 µm). [ABSTRACT FROM AUTHOR]

The kinetics of reactions between minerals and water vapor or two water phases simultaneously (liquid + vapor) is still understood inadequately poorly, and the absence of these data disable realistic and comprehensive quantitative description of the evolution of hydrothermal system after its fluid heterogenizes. To bridge this gap, we have conducted quenching experiments with quartz crystals and water at 300°C and Psat = 86 bar. In addition to usually applied analytical techniques (ICP-AES, SEM, XRD, and optical microscopy), we used 3d scanning of the crystals, measured their surface areas, and plotted the changes in the crystal sizes because of dissolution and deposition reactions. In the experimental runs with the crystal occurring in the vapor phase, the first ever data were acquired on the rate constant of quartz dissolution for saturated water vapor (Psat = 86 bar) at 300°C (2.7 nmol m–2 s–1). The constant turned out to be 630 times lower than that for pure water. Calculations indicate that equilibrium between quartz and water and vapor is established during comparable time spans, but quartz recrystallization in vapor due to the temperature gradient proceeds two orders of magnitude more slowly than in water. In the runs with the crystal occurring in both water and vapor, not only the stable quartz dissolved, but also metastable cristobalite-tridymite opal was formed. The opal was deposited on the autoclave walls and even on the quartz itself above the water surface, and the silica concentration in the water remained remarkably lower that the quartz solubility. The rate of opal formation (10–7.5 mol m–2 s–1) was 3.5 orders of magnitude higher than the quartz recrystallization rate (which is the only process possible in this system according to the traditional geochemical approach). This disagreement is explained within the framework of the distillation hypothesis, which is based on the preferential evaporation of the thin (<100 nm) solution layer at the meniscus edge. The system is found out to be able to evolve according to two scenarios, which result in the scattered and compact opal deposition because of the different ratios of the ascent velocity of the solution film and the evaporation rate. This phenomenon may explain the asymmetry of naturally occurring crystallization cavities, whose lower parts dissolved, and minerals were deposited in the upper parts. [ABSTRACT FROM AUTHOR]

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Traffic safety is current problem, and it is at the same time an important area for scientific research work, both on the global and from the national level. Traffic safety management is of great importance from the aspect of reducing the number of injured people in traffic accidents. Traffic safety management is possible through appropriate management models. Quality management system provides the possibility to manage in closed systems, or in organizations such as a transport company. This paper presents research on the possibilities of traffic safety management in transport companies based on performance indicators.