Use of High-Refractive Index Hydrogels and Tissue Clearing for Large Biological Sample Imaging

Recent advances in tissue clearing and light sheet fluorescence microscopy have improved insights into and understanding of tissue morphology and disease pathology by imaging large samples without the requirement of histological sectioning. However, sample handling and conservation of sample integrity during lengthy staining and acquisition protocols remains a challenge. This study overcomes these challenges with acrylamide hydrogels synthesised to match the refractive index of solutions typically utilised in aqueous tissue clearing protocols. These hydrogels have a high-water content (82.0 ± 3.7% by weight). The gels are stable over time and FITC-IgG readily permeated into and effluxed out of them. Whilst the gels deformed and/or swelled over time in some commonly used solutions, this was overcome by using a previously described custom refractive index matched solution. To validate their use, CUBIC cleared mouse tissues and whole embryos were embedded in hydrogels, stained using fluorescent small molecule dyes, labels and antibodies and successfully imaged using light sheet fluorescence microscopy. In conclusion, the high water content, high refractive index hydrogels described in this study have broad applicability to research that delves into pathophysiological processes by stabilising and protecting large and fragile samples.

A wide temperature range sensor based on large range strain self-healing and adhesive organogel

Traditional hydrogels have been widely studied in intelligent wearable, soft mechanical and biological medical applications due to their high water content and good biocompatibility. However, when hydrogels are used at...

Study on the Bearing Characteristics and Application of the Filling Body in Original Roadway Filling and Nonpillar Driving

Original roadway filling and nonpillar driving can effectively solve the difficulty facing mining replacement in the stope of deep mines. As the bearing characteristics of the filling body in the original roadway play a crucial role in the structural stability of the overlying strata, with the recovery and geological conditions of 62210 working face in Xinzhuangzi Coal Mine, Huainan Mining Group, China, as the background, this study analyzed the stability characteristics of the filling body in the original roadway through comprehensive research methods of theoretical analysis, laboratory tests, and onsite monitoring. The results disclose that the filling body in the original roadway should boost early strength, strong bearing capacity, and long-term weakening. When the water-cement ratios are 1 : 1, 1.5 : 1, 2 : 1, 2.5 : 1, and 3 : 1, the strengths of the filling body are 1.12 MPa, 0.93 MPa, 0.57 MPa, 0.33 MPa, and 0.21 MPa at 2 h and 5.63 MPa, 4.66 MPa, 2.87 MPa, 1.65 MPa, and 1.02 MPa at 48 h, respectively. The strengths surge by 5 times within 2 d on the whole and reach the maximum at about 7 d, i.e., 8.12 MPa, 6.91 MPa, 6.60 MPa, 3.95 MPa, and 2.20 MPa, respectively. As time goes, the water content of the filling body gradually decreases and the compressive strength plunges. This demonstrates that the rapid solidification material with a high water content can satisfy the requirements of the bearing characteristics of the original roadway filling body. With reference to numerical simulation and the data monitored onsite, it can be known that the filling body in the original roadway can support the roof effectively and control the surrounding rock deformation of newly excavated roadways in the lower section. The research results provide theoretical guidance for coal mining under similar geological conditions and serve as reference for safe and efficient coal mining.

Heat Transfer Limitations in Supercritical Water Gasification

Supercritical water gasification (SCWG) is a promising technology for the valorization of wet biomass with a high-water content, which has attracted increasing interest. Many experimental studies have been carried out using conventional heating equipment at lab scale, where researchers try to obtain insight into the process. However, heat transfer from the energy source to the fluid stream entering the reactor may be ineffective, so slow heating occurs that produces a series of undesirable reactions, especially char formation and tar formation. This paper reviews the limitations due to different factors affecting heat transfer, such as low Reynolds numbers or laminar flow regimes, unknown real fluid temperature as this is usually measured on the tubing surface, the strong change in physical properties of water from subcritical to supercritical that boosts a deterioration in heat transfer, and the insufficient mixing, among others. In addition, some troubleshooting and new perspectives in the design of efficient and effective devices are described and proposed to enhance heat transfer, which is an essential aspect in the experimental studies of SCWG to move it forward to a larger scale.

Adding Kaffir Lime (Citrus hystrix) Leaf Essential Oil to Gelatin Coating for Extending the Shelf Life of Red Snapper Fillet

Red Snappers contain high content protein and water which makes them highly perishable. However, they are widely processed into the fillet. One of the disadvantages of filleting is the short shelf life due to the high water content turning the fillets into an ideal media for bacteria. The edible coating protects the meat from perishability by reducing the water vapor, aroma, and lipid migration. One of the potential protein sources for coating is gelatin. The essential oil content that has a role in inhibiting bacterial growth is citronellal. The present study aimed to determine the effects of adding Kaffir limes (Citrus hystrix) leaf essential oil to a gelatin coating on the shelf life of red snappers’ fillet. An experiment was conducted using a completely randomized design with four treatment groups based on the concentration of Citrus hystrix essential oil and five replications (n = 3 per group). In this regard, the treatments were named P0 (0% of Citrus hystrix), P1 (1% of Citrus hystrix), P2 (1.5% of Citrus hystrix), and P3 (2% of Citrus hystrix). The investigated parameters included total plate count, sensory quality, and acidity. Data analysis was performed using ANOVA followed by Duncan’s multiple range test. The results showed that the addition of 1.5% and 2% Citrus hystrix essential oil decreased the number of bacteria, and led to a higher sensory quality. In conclusion, The addition of Citrus hystrix essential oil in the gelatin-coating process can be used as a method of processing the fishery products to extend the shelf life of red snappers’ fillet at room temperature and inhibit bacterial growth.

Influence of Dynamic Load on Soil Moisture Field in the Process of Freeze-Thaw Cycles

Due to climate warming and large-scale engineering activities, the embankment engineering risk in the permafrost and seasonally frozen regions caused by water content change in the soil has become more and more serious. To study the moisture migration law in the embankment under the vehicle load action and periodic variation of temperature, a series of temperature-controlled model tests under the dynamic load condition were carried out, the dynamic load was imposed by an air hammer connecting a vibration plate, which was installed on the top surface of the soil, and the variation law of the temperature and moisture fields in the model was analyzed. The test results show that the moisture field in the soil sample changes obviously with the increasing freeze-thaw cycles under the no-load condition, especially after nine freeze-thaw cycles, two moisture accumulation areas appear in the range of 8–15 cm from the soil surface; the dynamic load has an inhibitory effect on the moisture migration within 5 cm below the vibration plate and has a promoting effect on the range of 10–30 cm below the vibration plate. With the increase in the number of freeze-thaw cycles, three high-water content areas are gradually formed and approximately uniformly distributed within the 10–25 cm depth range of the soil, which has an important impact on the stability of the soil. The water content of the moisture accumulation areas during freezing is greater than that during thawing under the no-load condition, while the water content of the moisture accumulation areas during freezing is less than that during thawing under dynamic load. The research results can provide references for the embankment design and disease treatment in cold regions.

IDENTIFICATION OF FORMALDEHYDE IN UNBRANDED WET NOODLES AT TRADITIONAL MARKETS OF TAMBUN SELATAN USING TEST KIT METHODS AND UV-VIS SPECTROPHOTOMETRY

Introduction: Wet noodles are flour-based foods that are widely consumed by the community because of their easy processing. The high water content in wet noodles makes the noodles not last long. In fact, there is still a preservative in wet noodles that is not used, namely formaldehyde. The purpose of this study was to determine whether there was formaldehyde in unbranded wet noodles in the Traditional Market of South Tambun District and to determine the level of formaldehyde in unbranded noodles in the Traditional Market of South Tambun District. Method: This research was conducted at the STIKes Mitra Keluarga laboratory. The type of research used is descriptive. There are 7 samples taken from 4 different markets. The sample was tested using a formaldehyde test kit and resulted in 6 positive formaldehyde samples. According to SNI, formaldehyde should not be in wet noodles. So that the results of the 6 samples did not meet the quality requirements of wet noodles. Results: Furthermore, the positive sample was determined using a UV-VIS spectrophotometer and Nash reagent. The lowest level of formaldehyde is 18.61 mg/L while the highest level is 738.45 mg/L. Conclusion: First, the regulation is not yet known by the producers because it is classified as traditional. Second, there is no good control from authorized institutions or officers. Third, the lack of guidance for producers

Field Treatment of Storage Sludge and Stability Analysis of Overlying Municipal Waste Landfilling

Storage sludge has high water content and low shear strength, which limits the capacity expansion of overlying municipal landfilling. Few studies have addressed the field treatment of large amounts of storage sludge due to the variability of the depth of geotechnical property. This paper proposes a stratified treatment method for storage sludge, based on the in situ characterization of layered sedimentary patterns of the storage sludge acquired from the Qizishan landfill in China. Additionally, the stability of the landfilling above the sludge pond is analyzed using the Morgenstern–Price and limit equilibrium slice method, which considers the layered strength properties of solidified sludge. The treated sludge has a significant decrease in average water content from 1398% to 88% and an increase in average cohesion to 23.52 kPa. The high content of clay particles, low amount of solidification products, and high water content together result in the high sensitivity to the water content of the strength of deep solidified sludge. For a 40-m high waste body, stability analysis suggests a sliding surface across the raw sludge pond, while the critical surface remains outside the treated sludge pond and the safety factor is increased from 0.934 to 1.464. The validated stratified treatment provides valuable references for the treatment of deep sludge.

Interpretation of clearness day-ahead forecast errors using novel cloud classification

<p>        The formation and dissipation of clouds are one of the longest studied and yet least understood phenomenon in nature. This is crucial in atmospheric and climate science as clouds have a significant impact on radiative forcing. In numerical weather prediction, solar radiation forecasts have lower skill than other parameters as temperature forecasts despite recent progresses. This study aims at better understanding cloud situations over Europe and how solar radiation forecast errors are related to these situations. Therefore, an enhanced cloud class algorithm based on unsupervised Deep Learning and hierarchical clustering is introduced. By using the MODIS optical cloud thickness product, the algorithm is able to classify 14 different daily cloud situations which are applied on defined tile regions (approximately 70,000 km²) of Europe. These different classes differ in both optical cloud phase and the overall structure of the cloud shape. The usefulness of the cloud classes is illustrated by showing regional differences of cloud type frequencies over the last 20 years. To better understand solar radiation forecast errors, the cloud classes are assigned to ECMWF IFS clearness day-ahead forecast errors. We show that high-water content and mixed-cloud phase situations lead to highest absolute forecast errors for single sites. Summed up over an area, we observe an accumulation of forecast errors for mixed-cloud phase situations whereas for other cloud situations forecast errors are more likely to cancel each other out (e.g. broken high-water content clouds). This study is useful for researchers and practitioners to better understand situations of high solar radiation errors by using the developed cloud product.</p>