Uncovering quality changes of surimi-sol based products subjected to freeze-thaw process: The potential role of oxidative modification on salt-dissolved myofibrillar protein aggregation and gelling properties

Frozen surimi quality generally correlates with oxidation, but impacts of protein oxidation on salt-dissolved myofibrillar protein (MP) sol in surimi remain unclear. Hence, physicochemical and gelling properties of MP sol with different oxidation degrees were investigated subjected to freeze-thaw cycles. Results showed that mild oxidation (≤1 mmol/L) improved unfrozen MP gel quality with lowest cooking loss (3.29 %) and highest hardness (829.76 N). Whereas, oxidized sol suffering freeze-thawing degenerated severely, showing reduction of 23.85 % of salt soluble protein contents with H2O2 concentrations of 10 mmol/L. Shearing before heating influenced gelling properties of freeze-thawed sol, depending on oxidation levels. Oxidized gel with shearing displayed disorganized network structures, whereas gel without shearing displayed relatively complete appearances without holes under high oxidation condition (10 mmol/L). Overall, freeze-thaw process aggravated denaturation extents of MP sol subjected to oxidation, further causing high water loss and yellow color of heat-induced gel, especially to gel with shearing.

Pushing the limit of MQMAS for low-γ quadrupolar nuclei in pharmaceutical hydrochlorides

Solid-state NMR of quadrupolar nuclei such as ³⁵Cl has become a useful tool to characterize polymorphism in pharmaceutical hydrochlorides. The two-dimensional multiple-quantum magic-angle spinning (MQMAS) experiment can achieve isotropic resolution, and separate quadrupolar line shapes for samples with multiple sites but the pulse sequence efficiency is often low, limiting applications due to the intrinsically low NMR signals and rf field from the low gyromagnetic ratios γ. The use of cosine low-power MQMAS pulse sequences and high magnetic fields is presented to push the limit of MQMAS for insensitive low-γ quadrupolar nuclei. The improved efficiency and fields up to 35.2 T enable the acquisition of MQMAS spectra for pharmaceutical samples with multiple ³⁵Cl sites, large quadrupolar couplings and/or in diluted dosage forms.

Extrusion-based additive manufacturing of forming and molding tools

The production of rapid tools for plastic molding, sheet metal forming, and blanking has always been a critical and important goal for applied research, and a very large number of alternative methods have been proposed over the decades for their production. Among these methods, the use of extrusion-based additive manufacturing (EAM), such as fused filament fabrication (FFF) or similar technologies, has not been frequently considered and needs to be explored extensively. EAM is generally considered a low-cost, low-quality, low-performance class of AM and not suited to produce real functional parts, but only for aesthetical prototypes. However, the capabilities of EAM technologies have greatly evolved and now it is possible to extrude a wide range of materials such as polymeric materials including both the low strength polymeric materials (such as nylon or PLA) and the high strength polymeric materials (such as PEI and PEEK), metals (such as tool steel), and even ceramics (such as zirconia). Starting from an extensive literature review, the purpose of the present paper is to further demonstrate the potential applicability and versatility of EAM as a rapid tool manufacturing technology for different applications in shearing, bending, deep drawing, and injection molding.

Experimental study on microstructure and mechanical properties of stalk for Glycyrrhiza Glabra

In this paper, a year-old stalk of Glycyrrhiza glabra was used as the research object. The electronic universal testing machine was used to test the mechanical properties of shearing and bending. The microstructure of the stalk of Glycyrrhiza glabra was observed with a microscope. Mechanical test research indicated that the shearing process included an elastic phase, a yield phase, and a plastic deformation phase. The bending process was divided into elastic deformation stage and plastic deformation stage. In addition, the shearing force, shearing energy, bending force and bending energy all increased with the increase in diameter. As the water content increased, the shearing force and bending force decreased at first, reached the minimum when the water content was about 45%, and then had an upward trend. The shearing energy increased with the water content, and the bending energy, decreased with the water content. The two test factors were statistically significant for both shearing and bending properties. The microscopic test results showed that the phloem, fiber, and pith constitute the microstructure of the licorice stalk. The linear regression model could reflect the correlation between the cross-sectional area of each part and the shearing force and bending force (P < 0.05). Through analysis, it was concluded that the change of the cross-sectional area of the stalk microstructure had an important influence on the mechanical properties of shearing and bending. The results can provide theoretical basis for the design of Glycyrrhiza Glabra stalk harvesting, crushing and processing equipment.

Effect of diet quality and shearing on feed and water intake, in vitro ruminal methane production, and blood parameters of Omani sheep

The aim of this study was to evaluate the effect of diet and animal shearing on the feed and nutrient intakes, water intake, in vitro ruminal methane production, and blood parameters of Omani sheep. A pens trial was carried out for 16 days each in March and June of 2017 using 20 Omani non-castrated yearling rams selected from the sheep herd in the research station and randomly assigned to four groups with 5 animals per group. Group 1: sheared animals fed a high concentrate (HC) diet, group 2: fleeced animals fed a HC diet, group 3: sheared animals fed a low concentrate (LC) diet, group 4: fleeced animals fed a LC diet. Furthermore, a metabolic crates trial was carried out in July of 2017 on three animals from each group over a 10-day period. The effect of diet and shearing on the tested parameters was evaluated using the mixed linear model, where animals were fitted as a random effect to account for the individual animal deviation from the overall mean. Results showed that rams fed on the high concentrate diet had a significantly increased organic matter intake of the total diet (62 g/kg ^0.75 Live Weight (LW) in HC group to 54 g/kg ^0.75 LW in LC group), an increased water intake (6.3 L/day vs 4.8 L/day in LC group), and a reduced in vitro methane production (i.e. the invitro ruminal CH₄ was measured and converted to daily CH₄ using the daily feed intake data and was 20.4 g CH₄ per head/day in HC group vs 27.3 g CH₄ per head/day in LC group), compared with rams fed on the low concentrate diet. Furthermore, shearing had a significant effect (P < 0.01) on increased feed and nutrients intake. The apparent and organic matter digestibility was significantly different (P < 0.01) between the experimental groups and was greater for those rams fed on the HC diet. Partial substitution of low-quality Rhodes grass hay by high-quality concentrate significantly improved the total diet organic matter digestibility (P < 0.01) and nutrients digestibility, whereas no significant effects on biochemical blood parameters or animal health were observed. These results show the importance of utilizing effective feeding and shearing plans to improve the productivity and reduce the methane emission of Omani sheep.

Functional testing on engineered cartilage to identify the role played by shearing

Compressive loading is crucial for tissue regeneration in cartilage; however, the role played by shearing induced from translational or rotational motion of the knee joint has yet to be identified. This study aims at investigating the effects of in vivo like dynamic load-compression integrated with shearing on tissue regeneration, particularly to identify the role played by shearing induced from rotational motion. Tissue samples fabricated from a calcium alginate hydrogel embedded with chondrocytes were subjected to a dynamic tissue culture. Three culturing regimes were included: a static culture control (CON), compression combined with shearing induced from translational motion (CS), and compression combined with shearing induced from both translational and rotational motion (CSR). The results indicate that the CS group has a significantly larger chondrocyte proliferation rate (p < .01), and that the CSR group has no advantages over the CS group. However, the CSR group was found to have a marked influence on the matrix synthesis compared to that of the CS group (p < .01). It can be concluded that shearing from individual joint motions offers a different contribution to the chondrocyte proliferation, matrix synthesis, and phenotype maintenance, and better insight into these individual roles will be necessary for determining the efficacy of in vivo/vitro cartilageous tissue functionalization.

The fate of trace organic contaminants in sewage sludge during recuperative thickening anaerobic digestion

The aim of this work was to study the fate of trace organic contaminants (TrOCs) in sewage sludge during recuperative thickening anaerobic digestion. Sludge shearing at 3142s^-1 for 5minutes improved biogas production. By contrast, shearing at ≥6283s^-1 for 5minutes caused a notable reduction in biogas production and the removal of volatile solids. Results reported here showed the prevalent occurrence of 17 TrOCs in sewage sludge and highlights the importance of assessing TrOC removal via mass balance calculation by taking into account partitioning between the aqueous and solid phase as well as biodegradation. Hydrophilic and readily-biodegradable TrOCs (caffeine, trimethoprim, and paracetamol) were well removed and were not affected by shearing. TrOCs such as carbamazepine, gemfibrozil, and diuron showed biodegradation only at high shearing. It is possible that shearing can facilitate the circulation of TrOCs between aqueous and solid phases, thus, enhancing the biodegradation of some TrOCs.

Fluid signal changes around the knee on MRI are associated with increased volumes of subcutaneous fat: a case-control study

Background

Fluid in the subcutaneous fat is a common finding anterior to the knee on MRI. This may be caused by chronic low-grade shearing injuries in patients who are overweight. The purpose of this study was to determine if there is a difference in the amount of subcutaneous fat around the knee between patients with these appearances and controls.

Methods

This was a retrospective case-control study. Following a sample size calculation on pilot data, eighteen sequential patients demonstrating hyper-intense subcutaneous signal changes around the knee on fat-saturated T2-weighted MRI were identified from PACS (18 females, mean age 45, range 31–62). Age and gender-matched patients without abnormal T2 MR signal changes were selected. Two observers independently drew regions of interest representing cross-sectional areas of bone and fat. The location of T2 signal hyper-intense lesions was characterized by consensus.

Results

Inter and intra-rater intraclass reproducibility was “excellent” (ICC > 0.8). The mean cross-sectional area of bone for patients with T2 hyper-intense lesions was 31.79cm² (SD 2.57) and for controls 30.11cm² (SD 3.20) which was not significantly different (p = 0.09). The median cross-sectional area of fat for the study group was 62.29cm² (IQR 57.1–66.5) and for controls was 32.77cm² (IQR 24.8–32.3) which was significantly different (p < 0.0001). Consensus agreement demonstrated all T2 hyper-intense lesions were anterior to the knee extensor mechanism.

Conclusion

Subcutaneous fluid around the knee is associated with an increased amount of subcutaneous fat, anterior to the knee extensor mechanism. This may be caused by shearing injuries in fat with reduced elasticity associated with metabolic syndrome.

Mechanical dissociation of the M-band titin/obscurin complex is directionally dependent

Titin and obscurin, two giant muscle proteins, bind to each other in an antiparallel Ig-Ig fashion at the M-band. This interaction must be able to withstand the mechanical strain that the M-band typically experiences and remain intact. The mechanical force on these domains is likely exerted along one of two axes: a longitudinal axis, resulting in a 'shearing' force, or a lateral axis, resulting in a 'peeling' force. Here we present molecular dynamics data suggesting that these forces result in distinct unraveling pathways of the titin/obscurin complex and that peeling the domains apart requires less work and force.

Sheep shearing and sudden death

A 29-year-old sheep shearer collapsed after walking across a shearing shed floor, holding his hand over an incised wound to his neck. Attempted resuscitation was unsuccessful. At the death scene fine arterial blood spatter was noted and at autopsy a single incised wound to the neck was observed, the patterned edges of which corresponded to the teeth of the shears. Dissection revealed injury to the underlying jugular vein and the mid portion of the common carotid artery. Death was attributed to blood loss from an incised wound of the left side of the neck. This case demonstrates the rare event of an accidental death related to the actions of a sheep. Although a relatively small animal, review of the circumstances and interviews with those present revealed that sudden and unexpected movement of the sheep during shearing had caused the shearer to lose control of his electrical shears resulting in a lethal incised wound to the neck. The blood spatter pattern at the scene was supportive of both witness descriptions and the findings at autopsy.