Time Of Sample Research Articles

The Effects of Modified Atmosphere Packaging on the Quality Properties of Water Buffalo Milk's Concentrated Cream.

Concentrated cream (CC) is a dairy product containing more than 60% milk fat. CC has a very short shelf life because it is made from unripe cream. The present study aims to determine how packaging with reducing gas (H2) and nitrogen (N2) affects the quality properties and shelf life of CC. For this purpose, lipolysis, oxidation, color, microbiological, and free fatty acid development and the fatty acid composition of modified atmosphere packaged (MAP) CC samples were studied for 28 days. For MAP1, 96% N2 + 4% H2 was used, and for MAP2, 100% N2 and air was used for the control group. During storage, MAP1 samples remained at lower lipolysis (ADV and FFA) and oxidation levels than MAP2 and the control group. The MAP1 and MAP2 methods preserved the color of the samples and reduced the microbial growth rate. A lower formation of free fatty acids was observed in the samples packed with MAP1 and MAP2 than in the control group. The results showed that hydrogen gas positively affected the quality and storage time of samples.

Effects of storage temperature and relative humidity on cooking time and moisture uptake of selected common bean ( Phaseolus vulgaris L.) varieties grown in Ethiopia

Common beans (Phaseolus vulgaris L) are important legumes rich in nutrients. However, the defect to cook or hard-to-cook (HTC) defect is among the challenges of legume crops during storage. Hence, this study aimed to determine the effects of storage temperature and relative humidity (RH) on cooking quality and moisture uptake of the selected recently released common bean varieties. Different storage conditions combinations were used for the analysis: ambient storage at 25°C and 65% RH as control storage; storage conditions of 35°C and 75% RH; and 35°C and 85% RH were explored. Zoasha, Nasir, Awash Weten and control bean varieties show reduced moisture uptake and increment in cooking time. The moisture uptake of Zoasha reduced from 127% immediately measured after harvesting to 79% (45°C/85%RH). Nasir, Awash Weten and the control sample varieties of beans reduced their moisture uptake from 121% to 74%, 124% to 75% and 142% to 90%, respectively. Those results show that accelerated storage conditions had a significant (P ≤ 0.01) effect on the moisture uptake. The initial cooking time of Zoasha, Nasir, Awash Weten and control samples were 101 minutes, 104 minutes, 101 minutes and 89 minutes, respectively. But, at accelerated storage conditions, the cooking time increased significantly (P ≤ 0.01) by 120%, 117%, 95% and 115%, respectively, for Zoasha, Nasir, Awash Weten and control sample varieties. At accelerated storage condition, the control sample should have the lower energy consumption by decreasing the cooking time by 25%, 22% and 20% from Zoasha, Nasir and Awash weten, respectively. The result could give an insight for food processors, breeders and policymakers to consider the hard-to-cook effects for the aforementioned common bean varieties.

Experimental Study of the Effect of Different Air Gap Orientations on Performance of Fire Protective Clothing

The effect of both horizontal and vertical air gap orientations on the heat transport through the fabric-air gap arrangement and on the thermal protective performance of the clothing is analyzed experimentally using two different setups, Horizontal Thermal Protective Performance Tester, and Vertical Thermal Protective Performance Tester. The fabric ensembles are exposed to a direct flame exposure of 60 kW/m2 for an exposure period of 10 s. Variation of temperature rise with time is determined for single and multilayer fabric ensembles for both orientations at different air gap widths. Burn time and thermal protective performance of the fabric samples is evaluated for the same. Effect of using different fabrics on the performance of fire protective ensemble is also discussed. Both repeatability and uncertainty analysis has been performed for the setups to ensure the reliability of the data.

Numerical simulation study on suppression effect of water mist on PMMA combustion under external radiant heat flux

Numerical model was built with fire dynamic simulator and theocratical simulation was carried out to investigate the suppression effect of water mist on ignition and combustion process of typical solid material polymethyl methacrylate under external radiant heat flux. Characteristic parameters such as ignition time, surface temperature, heat release rate and temperature distribution of flame central plane during ignition and combustion process under different thermal radiant fluxes were obtained and compared with experimental results. The suppression effect of spray droplets on ignition and combustion process was analyzed and discussed. The results show the theoretical calculations of combustion characteristic parameters are in good agreement with experimental measurements. Water mist droplets can effectively delay the ignition time. Quantitative data proves that the water mist flow rate at 0.9 L/(min·m2) can delay the ignition time of samples by about 1,100 s while the radiant heat flux is 50 kW/m2. The simulation results can provide theoretical support and data reference for typical solid material fire prevention and fire extinguishment in practice.

Evaluation of a Cross-Conductance Sensor for Cement Paste Hydration Monitoring and Setting Time Measurement

In this article, a sensor for monitoring hydration and detecting initial and final setting timings of freshly mixed cement paste is presented. It is a new application of a cross-conductance sensor and possesses the advantages of the cross-conductance approach, i.e., the output is sensitive only to the conductivity of the medium other than the length of the electrode. The new sensor overcomes several limitations of the conventional Vicat apparatus (VA) and other existing impedance-based schemes. The cross-conductance sensor cell is designed with the help of finite element analysis. The cell has four conductive electrodes separated by small gaps. It is fabricated using inexpensive but reliable materials. A simple measurement circuit is developed to obtain an output due to a change in the conductance of the sensor cell. The output of the sensor unit gives the conductance versus time response of the sample. From the rate of change of this output, the setting time of the cement paste samples is determined. The proposed sensor is simple to realize and it does not require calibration. The repeatability of the prototype sensor unit is found to be 1.5%. With the help of the fabricated sensor, the initial and the final setting timings of the cement paste samples are measured with an accuracy of ±2%.

SnS2/AuNPs surface-enhanced Raman scattering sensor for rapid and selective quantification of methimazole in serum and meat samples

Rapid and selective quantification is a great challenge for on-site analysis and point-of-care detection. Herein, we developed a SnS2/AuNPs sensor for quick and selective surface-enhanced Raman scattering (SERS) determination of methimazole in clinic serum and meat samples. SnS2/AuNPs hybrid with adjustable size, electromagnetic field enhancement, and surface plasmon resonance was facilely prepared by ultrasonic assistance. The SnS2/AuNPs sensor exhibited good SERS sensing performances for methimazole detection: a high enhancement factor of 4.5 × 107, good intra-batch uniformity with RSD of 6.1 % (n = 27), good batch-to-batch stability with RSD of 6.6 % (n = 15), and good selectivity to thyroid antagonists possibly due to the lowest energy charge transfer. Subsequently, a rapid SERS sensing method was established for quantitative analysis of methimazole ranging from 5 to 1000 µg/L with a detection limit down to 2.7 µg/L. Clinic serum samples from eight patients were accurately found with concentrations of 86.5–345.9 µg/L, recoveries of 89.7–104.7 % and RSDs of 2.1–8.8 %. The whole analysis time of clinic serum samples could be finished in 10 min without any pretreatment. The sensor with good sensitivity, reproducibility, and selectivity possessed great values for rapid food safety analysis and point-of-care detection in clinic diagnosis.

Ejecta cloud distributions for the statistical analysis of impact cratering events onto asteroids’ surfaces: A sensitivity analysis

This work presents the model of an ejecta cloud distribution to characterise the plume generated by the impact of a projectile onto asteroids surfaces. A continuum distribution based on the combination of probability density functions is developed to describe the size, ejection speed, and ejection angles of the fragments. The ejecta distribution is used to statistically analyse the fate of the ejecta. By combining the ejecta distribution with a space-filling sampling technique, we draw samples from the distribution and assigned them a number of representative fragments so that the evolution in time of a single sample is representative of an ensemble of fragments. Using this methodology, we analyse the fate of the ejecta as a function of different modelling techniques and assumptions. We evaluate the effect of different types of distributions, ejection speed models, coefficients, etc. The results show that some modelling assumptions are more influential than others and, in some cases, they influence different aspects of the ejecta evolution such as the share of impacting and escaping fragments or the distribution of impacting fragments on the asteroid surface.

The effect of maturation conditions on physicochemical and viscoelastic properties of Kashkaval cheese

Abstract The equilibrium stress, decay stress, relaxation time, viscosity, modulus of elasticity, and decay modulus are major characteristics of viscoelastic food materials and therefore a modified mechanical model was used in this current research for the viscoelastic properties’ evaluation of Kashkaval cheese. Also, the chemical composition (fat content, moisture, protein content, water activity, salt, and acidity), and inside-outside color of the Kashkaval cheese were studied. From the analysis of stress relaxation curves the analyzed cheese samples fall into the category of viscoelastic solids with equilibrium stress greater than 0. The decay stress and decay modulus of the maturated unpacked samples showed the highest values of 36.31 kPa and 121.05 kPa, while the relaxation time of cheese samples was greater than 112.35 s. To evaluate the fit of the applied mechanical model to the experimental data the determination coefficient (R2 > 0.937) and the absolute average deviation coefficient were calculated (AAD < 10.324) and the evaluated cheeses’ parameters with the modified Maxwell model were at statistically appropriate levels.

Development of Ultrasonic Kinematic Viscometer Based on Liquid Flow Through Bottom Hole

The development of a kinematic viscometer based on the ultrasonic sensing method is reported in this letter. In the proposed method, an ultrasonic sensor mounted on top of a liquid tank with a small hole at the bottom is used for measuring the viscosity of Newtonian liquid samples. The ultrasonic sensor in association with a data acquisition system is exploited to monitor the level of the flowing liquid through the bottom hole of the liquid tank and to measure the flow time of the liquid samples. The proposed system is utilized for measurement at temperatures of 20 °C, 30 °C, and 40 °C. The experimental result agrees with the results of standard viscosity of the test samples within the percentage error of 0.14%–5.11%. The merits of the proposed system are simple in design, low cost, very precise and repeatable, noninvasive, automatic flow time measurement, and better response time due to the use of the ultrasonic sensor. The proposed system can be employed for measuring the viscosity of all types of Newtonian liquids independent of their transparency or color.

The Effect of Total Laboratory Automation on Urine Culture Result Times in a Consolidated Laboratory.

The Provincial Health Directorate of Istanbul province (Turkey) established a consolidated laboratory network consisting of four regional central laboratories to reduce general laboratory costs and increase laboratory efficiency and quality in all affiliated hospitals. As part of the consolidation project, the Total Laboratory Automation (TLA) system was installed in the microbiology department of the ISLAB-2 central laboratory. In this study, the turnaround time (TAT) of urine samples of a satellite laboratory where the system was not installed and the ISLAB-2 central laboratory were compared to evaluate the effect of consolidation and the TLA. The TAT values of all urine samples processed between March 2021, when the TLA was installed, and October 2021, were retrospectively examined in the laboratory information system. While the TLA was used for the processing and evaluation of samples in the ISLAB-2 central laboratory, manual methods were employed in the satellite laboratory. Both laboratories used MALDI-TOF MS (bioMérieux, France) for bacterial identification and VITEK 2 Compact (bioMérieux, France) for antibiotic sensitivity testing. Kruskal-Wallis test was used to compare TAT between the two laboratories. p < 0.05 was taken as the level of statistical significance. A total of 78,592 urine cultures (71,906 in the central laboratory and 6,686 in the satellite laboratory) were included in the study. Negative samples were reported in 23.5 hours in the central laboratory and 37.1 hours in the satellite laboratory and positive samples in 55 hours and 61.7 hours in the same laboratories, respectively. The mean TAT of both positive and negative urine cultures were found statistically significantly lower in the central laboratory than in the satellite laboratory (p < 0.0001). While 82% of negative urine cultures were completed within the first 24 hours in the central laboratory, only 17% were processed in the satellite laboratory. While 61% of positive samples were processed within the first 48 hours in the central laboratory, 38% were completed in the satellite laboratory. We assume that TLA has a positive effect on the diagnosis and treatment of patients, thanks to its contribution to standardization, efficiency, increased quality, and earlier reporting.

Biodegradation properties of natural fibers for agro textile nonwovens production

The aim of this paper is to investigate biodegradation properties of PLA (as a bio-based polymer), Hemp, Jute (as natural bast fibers) and Viscose (as a cellulose regenerates) for agrotextile nonwovens production. For the purpose of those investigations, an analysis of the biodegradation time of samples were performed by soil burial test (ISO 11721 – Textiles – Determination of resistance of cellulose-containing textiles to microorganisms – Soil burial test) conducted under controlled conditions in laboratory and under real weather conditions. The samples were exposed in the soil for 4, 7, 9 and 11 days. An analysis of mass loss and changes in their mechanical properties, compared to unexposed samples, were determined.

Determination of Physicochemical, Cooking and Milling Characteristics of Four Nigerian Rice Varieties

This research work determined the physicochemical, cooking and milling characteristics of four Nigerian rice varieties namely Illa from Southern, Abakaliki South-East, Jemila North and Ofada from West.The physiochemical, milling and cooking properties of rice are solely determining the preference, choice and economy of rice. The four rice varieties grown in different region in Nigeria were investigated for cooking, milling and physical, cooking and chemical characteristics. The result from axial dimension classified all the studied rice varieties as long grains. Illa rice recorded highest value (43.96 g) of 1000 grain weight while lowest value of 20.46 g was observed in Ofada rice. The variation in grain shape were not significant at (P&amp;gt;0.05) and all the tested varieties fall within the slender shapes. All the tested samples displayed good Milling behavior. Ofada rice elongated more than other varieties. The broken percentage was higher and lower in Illa rice (36.72%) and Abakaliki (28.78%) respectively. There were similarities in milling recovering of rice varieties, but Illa had highest expansion (swelling) capacity while Ofada had lowest swelling power. Amylose and gelatinization temperature showed a good relationship, Ofada rice with higher amylose content had lowest gelatinization temperature. The determined cooking time of the rice sample varied from 5.56 to 6.77 mins, Jemila rice will cook faster than other varieties. Illa rice had highest value (353.76%) of water absorption capacity, followed by Abakaliki rice with 185.76% Water Absorption Capacity and Ofada rice which had 158.62% WAC. The lowest value (155.60%) of Water Absorption Capacity was found in Jemila rice variety.

Rare earth inorganic-organic hybrid compounds based on Keggin-type polyoxometalate {SiW12} with fast-responsive photochromism and switchable luminescence properties

Four rare earth inorganic-organic hybrid compounds based on Keggin-type polyoxometalate {SiW12} with general formula [{RE(DMF)4(H2O)4RE(DMF)6}2{SiW12O40}3] (RE = La(1), Pr(2), Sm(3), Eu(4), DMF = N,N-dimethylformamide) were synthesized by the conventional solution method. Structure analyses indicate that four compounds are isostructural and are all built from three [SiW12O40]4– polyoxoanions and DMF ligands linked by RE3+. Compounds 1–4 are extremely sensitive to UV light and present excellent photochromic properties, in which the coloring and fading time of samples are both no more than 2 min, and the reversible coloring-fading process can be repeated for at least 10 cycles with little fatigue, suggesting that compounds 1–4 can be a series of fast-responsive and durable photochromic materials. Moreover, the solid-state photoluminescence spectra of compounds 3(Sm) and 4(Eu) display strong characteristic emissions of rare earth ions based on f–f transitions. Meanwhile, compound 4(Eu) has a longer fluorescence lifetime up to 566.74 μs. Notably, compounds 3(Sm) and 4(Eu) exhibit the switchable luminescence behavior induced by photochromism, which allows them to be used as potential molecular switches.

Second trimester cytokine profiles associated with gestational diabetes and hypertensive disorders of pregnancy.

Healthy pregnancy requires a coordinated immune response, yet complications can arise, putting both the mother's and child's health at risk. Hypertensive disorders of pregnancy (HDP) and gestational diabetes mellitus (GDM) are pregnancy-related complications that account for most maternal morbidity and mortality. Cytokines are proteins released as part of the immune response to disease or infection and regulate inflammation. Certain pregnancy complications cause localized and systemic inflammation; however, cytokine profiles specific to such complications are not well understood. This study aims to examine associations between pregnancy complications of HDP and GDM and cytokine profiles in the second trimester of pregnancy. Data was obtained from the All Our Families birth cohort in Calgary, Alberta, Canada. The cohort collected questionnaires at the time of participant enrollment and maternal blood samples at 17-23 weeks gestation. Cases of HDP (n = 27) and GDM (n = 31) were matched to controls on BMI, maternal age, and smoking status in the preconception period at a 1:3 ratio. Cytokine levels were measured in blood samples using Luminex xMAP technology using a panel of 42 cytokines. Using R software, a Classification and Regression Tree (CART) analysis was conducted to identify cytokine profiles and levels associated with each complication. Four cytokines were identified in the HDP CART (in descending order of importance): Monocyte Chemoattractant Protein-1 (cut-off: <480pg/mL), Macrophage Inflammatory Protein-1β (cut-off: ≥26pg/mL), Eotaxin (cut-off: <27/≥27&<36/≥36pg/mL), and Soluble Cluster of Differentiation 40 Ligand (cut-off: <1342pg/mL). Six cytokine levels were identified in the GDM CART: Interleukin-1 Receptor Antagonist (IL-1Ra; cut-off: <25pg/mL), Interleukin-5 (cut-off: ≥0.4pg/mL), Interferon-γ (cut-off: <4.9pg/mL), IL-1Ra (cut-off: ≥111pg/mL), Eotaxin (cut-off: ≥21pg/mL), and Interleukin-18 (cut-off: ≥155pg/mL). By examining the complex inter-relationships between cytokines, findings of cytokine profiles guide further research in identifying biomarkers of pregnancy complications relevant to the design of the future management or prevention of these conditions.

Assessing Tissue Fixation Time and Quality with Label-free Mid Infrared Spectroscopy and Machine Learning.

Objectives: This work investigates whether changes in a biospecimen's molecular composition from formaldehyde fixation drive changes in the mid infrared (MID-IR) spectrum. Our ultimate goal was to develop an analytical metrology that could be used to accurately determine the fixation time of a tissue sample as a surrogate to overall tissue quality. Methods: Multiple unstained formalin-fixed paraffin-embedded tissue samples were scanned with an MID-IR microscope to identify a molecular fingerprint of formaldehyde fixation. The fixation specific patterns were then mined to develop a predictive model. A multiple tissue experiment using greater than 100 samples was designed to train the algorithm and validate the accuracy of predicting fixation status. Results: We present data that formaldehyde crosslinking results in alterations to multiple bands of the MID-IR spectra. The impact was most dramatic in the Amide I band, which is sensitive to the conformational state of proteins. The spectroscopic fixation signature was used to train a machine-learning model that could predict fixation time of unknown tissues with an average accuracy of 1.4 hours. Results were validated by histological stain quality for bcl-2, FOXP3, and ki-67. Further, two-dimensional imaging was used to visualize the spatial dependence of fixation, as demonstrated by multiple features in the tissue's vibrational spectra. Conclusions: This work demonstrates that it is possible to predict the fixation status of tissues for which the preanalytics are unknown. This novel capability could help standardize clinical tissue diagnostics and ensure every patient gets the absolutely best treatment based on the highest quality tissue sample.

Study on Multi-Factor Optimization and Application for Water Mist of a Wetting Dust Suppressant.

Aiming at the problem of low efficiency of capturing respirable and hydrophobic dust in water mist dust removal technology, a chemical dust suppression method is adopted. Based on the research idea of improving the wetting efficiency of water mist, prolonging the droplet retention time, and improving the contact opportunity with dust, the experiments of dust sedimentation time, solution spreading area, and water loss rate are selected to evaluate the wetting efficiency and anti-evaporation performance of dust suppression water mist. Considering the special double-chain structure of the Gemini surfactant and its high wettability, it is preferred as the main dust suppression component. Based on the indoor experimental data, the optimized formula of the composite wet water mist dust suppressant was obtained by CCD-RSM(central composite design-response surface methodology). The comparison of indoor experimental data shows that the sedimentation time of the dust sample in the water mist dust suppressant is 5.0 times faster than that of pure water, the spreading area of the dust suppressant solution is 1.8 times that of pure water, and the water loss rate of the dust sample treated by the dust suppressant is 70% that of pure water. The field investigation results show that compared with pure water mist, the dust removal rates of the Gemini wetting dust suppressant for respirable dust and total dust are 90.3 and 71.1%, respectively, which are 10.5 and 22.5% higher than that of pure water mist. It can be proved that improving the wetting efficiency and anti-evaporation performance of spray mist will increase the dust removal efficiency.

Improving low temperature degradation of 3Y-TZP ceramics via high temperature carburizing

3Y-TZP ceramics are prepared by solid state method and surface carburization process, and the effect of surface carburization on its the low temperature degradation is studied. The conventional sintered samples completely lost its mechanical properties after aging for 15 h, while the failure time of the surface carburized samples are 300 h. In addition, the nuclear growth rate of the surface carburized samples (αd) and the nucleation rate (Nr) is lower than that of sintered samples, αd plays a dominant role in the degradation process at low temperature and is the key factor determining the aging rate. At the same time, it is found that carbon is dissolved in zirconia lattice in the form of electrically neutral atoms, which will not destroy the original charge balance and produce new oxygen vacancies when entering the interstitial site. More importantly, the precipitation rate of Y3+ from zirconia lattice is the key factor to determine the low-temperature phase transition of tetragonal-monoclinic(T-M). The treatment method of surface carburization has significantly improved the low-temperature degradation performance of 3Y-TZP ceramics, which provides a basis for the application of zirconia ceramics in low-temperature and humid environment.

On-site leakage locating of underground natural gas pipeline based on Ne tracer by miniature time-of-flight mass spectrometry

Natural gas pipeline leakage seriously endangers people's lives and properties, and there is an urgent need for on-site, rapid, and accurate locating the leakage point of the underground natural gas pipeline. Here, we added neon gas to natural gas pipelines as a tracer gas, and used a miniature time-of-flight mass spectrometry (mini-TOFMS) to on-site detect neon gas to quickly locate the leak point of underground natural gas pipelines. The mini-TOFMS used capillary tube sampling to directly analyze the leaked neon gas without sample preparation, and the analysis time of a single sample was only 60 s, which was less than one-seventeenth that of traditional off-line gas chromatography (GC) method. The mini-TOFMS exhibited a linear response range from 69 ppmv to 3.0 × 105 ppmv with the limit of detection (LOD, S/N = 3) of 19.0 ppmv. The correlation of GC and mini-TOFMS for Ne quantitative analysis was as high as 0.98. The performance of the newly designed method with the mini-TOFMS was demonstrated by on-site locating the underground natural gas pipeline leakage point in the experimental station. And leakage point of the natural gas pipeline, especially for those pipelines with different gas pressure buried under the same road, can be found more efficiently and accurately.

Increase of milk heat stability by addition of casein glycomacropeptide

The effect of caseinglycomacropeptide (CMP) addition on the heat stability and physicochemical characteristics of milk was studied. The heat coagulation time (HCT) of milk samples with different CMP concentrations added were analysed and was observed that HCT increased when CMP was added in concentrations between 0.4 and 1.25% (w/w). Therefore, a more detailed physicochemical study was carried out in milks with CMP concentrations of 0.4, 0.6 and 0.8% (w/w). Also, the effect of two heat treatments to milk with CMP addition, applying conditions similar to UHT and in container sterilisation, was monitored. Two opposing effects were observed. On the one hand, CMP bound calcium conferring heat stability and, on the other, increased total electrical conductivity decreased the pH, slightly destabilising serum proteins and, hence, inducing colloidal instability. Therefore, there is a concentration range in which this peptide may act as heat stabiliser and as a nutritional additive in milk.

Research Progress on Separation and Detection Methods of Microplastics in Soil Environment

As a new type of environmental pollutant, microplastics (MPs) exists in the soil environment for a long time and pollutes the ecological environment of the surface system. Separation and detection of microplastics in soil environment is the basis of controlling microplastics pollution in soil environment. The research progress of separation and detection technology in microplastics was introduced, and the existing problems of separation and detection methods were put forward. The results show that the screening-filtration method and density separation method are simple, operable and effective, but the cross-contamination rate is high in the extraction process, and the recovery rate of high-density microplastics is not high. Pressurized fluid extraction technology is convenient and easy to operate, but it may affect the particle morphology of microplastics. Visual detection, Raman and infrared spectroscopy, chromatography and mass spectrometry combined pyrolysis analysis have some problems, such as high cost, long time and loss of samples. In the future, it is necessary to further explore the analytical method of microplastics, and develop the separation and detection method without loss of microplastics.