Changes In Tension Research Articles

High pressure salt water and low temperature effects on the material performance characteristics of additive manufacturing polymers

The effects of salt water exposure at deep ocean depth pressures when coupled with low temperatures on the material characteristics of three unique additively manufactured polymers has been investigated through a detailed experimental approach. The polymers in the study were manufactured utilizing both Vat Photopolymerization and Material Extrusion printing techniques. The Material Extrusion process was utilized to produce material specimens of Stratasys ULTEM 9085 and Markforged Onyx while the Vat Photopolymerization process was used to produce specimens of Accura ClearVue. The ULTEM 9085 and Markforged Onyx are filament based polymers and the ClearVue is a liquid based resin. The specimens were first submerged in a high pressure, salt water bath of 3.5% NaCl solution at 34.5 MPa (5000 lb/in2) for a total exposure time of 60 days to determine the water absorption characteristics. Subsequent to the salt water exposure at high pressure, the specimens were evaluated to determine changes in tension, compression, flexure, and in-plane fracture properties. To determine the effects of water saturation and low temperature coupling, the mechanical testing was performed at temperatures of 20 °C, 0 °C and −20 °C in both dry and saturated conditions. Additionally, non-destructive testing in the form of TeraHertz and FIRT imaging was conducted to analyze the physical material changes through the thickness of the material due to the saline water absorption. To quantify the change in material storage and loss moduli properties, Dynamic Mechanical Analysis (DMA) characterization was performed on each of the AM polymers in dry and saturated states. The DMA testing also quantified changes in the Glass Transition Temperature because of salt water exposure. In summary, The current study investigates the effects of coupled long term/high pressure salt water exposure with low temperatures on the mechanical and material characteristics of three unique AM polymers by: (1) immersing the materials in a salt water solution at 34.5 MPa for 60 days, (2) Conducting post exposure mechanical testing on the materials at 0 °C and −20 °C with comparisons to 20 °C testing on dry specimens, and quantifies changes in material properties through DMA experiments. The results from all testing in the study show that high pressure salt water exposure when coupled with low temperatures has unique effects on each of the materials considered in the study and careful consideration to each parameter must be given based on the material type when components will be employed in marine operations.

Developing and validating an implantable suture tension sensor

IntroductionSuture tension has a direct influence on the sutured tissue. For abdominal wall closure, suture tension should be optimal without causing tissue necrosis, which can result in surgical site infection or incisional hernia. The purpose of the present study is to evaluate a device that can measure suture tension in-situ and in real-time. Materials and methodsA cheap, commercially available analog-to-digital converter was used, in conjunction with a force sensing resistor. A sensor probe housing was designed and 3D-printed. In order to test the sensor, a mechanical, computer controlled human abdominal wall model called the AbdoMAN was used. ResultsAn implantable suture tension sensor was developed, keeping cost-effectiveness in mind. This sensor can translate tension in the suture into a downward force, applied to the force sensing resistor. The sensor's raw readout was characterized using a set of weights, from which a formula correlating the readout to a specific force, was derived. Preliminary validation was successfully performed using the AbdoMANmodel, which showed a progressive rise in suture tension when the intra-abdominal pressure was artificially increased over time. ConclusionThe implantable suture tension sensor appeared to be capable of recording real time changes in suture tension, and the. validation process of this sensor has been initiated. With the information from devices like this, a much better understanding of the issues at play in the development of incisional hernia can be gained.

The role of calcium in neuronal membrane tension and synaptic plasticity.

Calcium is a primary second messenger that plays a role in cellular functions including growth, movement and responses to drugs. The role that calcium plays in mediating communication between neurons by synaptic vesicle release is well established. This review focuses on the dependence of the physical properties of neuronal plasma membranes on calcium levels. After describing the key features of synaptic plasticity, we summarize the general role of calcium in cell function and the signaling pathways responsible for intracellular increase in calcium levels. We then present findings showing that increases in intracellular calcium levels cause neurites to contract and break synaptic connections by changes in membrane tension.

Does Sertraline Affect Contraction in Endothelium Damaged Aorta

Aim: Selective Serotonin Reuptake Inhibitor (SSRI) group antidepressants are frequently used in heart patients. In the study, we aimed to investigate the effects of sertraline (SE) on aortic contraction on healthy/damaged rat aorta. Materials and Methods: Wistar albino rats (24) were divided into group1-aorta-intact endothelium and group2-aorta-damaged endothelium. The isolated aortic tissues were placed in organ baths. Changes in the isometric tension of the aortic rings were recorded. Contractions were recorded in both groups after the application of phenylephrine (PE 10-6M). Afterwards, cumulative sertraline (SE 50 mg) (10-9-10-4M) was given to group 1. In Group 2, to control aortic endothelial damage, acetylcholine (10-6M) was applied and the tissues were washed for an hour, the second dose of PE was given, then SE was given cumulatively (10-9-10-4M), and contractions were recorded. Results: After cumulative SE (10-9-10-4M) was given to Group 1, a significant inhibition in spontaneous contractions was detected in the first three sertraline doses (10-9,10-8,10-7)(p<0.05), and in the remaining sertraline doses contraction inhibition continued. When comparing SE 10 6,-5,-4 and 10-9,-8,-7 doses, there was inhibition of contractions (p<0.005). In group2, the inhibition of second PE contractions continued after sertraline doses, but the inhibition was observed less than in group1 (p<0.05). Conclusion: SE inhibited PE-induced smooth muscle contraction in rat isolated aorta. PE-induced smooth muscle contractions were inhibited more slowly in the endothelium-damaged aorta. It is thought that NO release and NO-dependent vasodilation in the aorta decrease as a result of damage. A clearer understanding of the effects of sertraline on the cardiovascular system will be possible with further research. Keywords: Aorta, endothelium, sertraline, contraction, vasorelaxation

Vision-based detection of bolt tension considering non-rotatory loosening via a new calculation method of bolt flexibility coefficient

Bolted joint is widely used in construction, vehicle, aerospace, and other engineering fields. Bolt tension is the most important performance index of bolted joints. The whole life cycle monitoring of bolt tension without contact and damage can be realized by vision-based method. The existing methods indirectly predict the change of bolt tension by calculating the rotary angle of the nut. This kind of method can judge the loosening caused by nut rotation but cannot deal with the non-rotary loosening. At the same time, the relationship between nut rotation angle and loosening must be obtained through calibration experiments. This paper proposes a vision-based method to measure the change of bolt tension considering the non-rotary loosening by detecting the change of bolt elongation. Based on VDI2230 and finite element analysis, a new calculation method of bolt flexibility coefficient is proposed. The experimental results show that this method can measure the change of bolt tension with high precision in the process of tightening and loosening.

Analysis of metallurgical defects in enamel steel castings

Abstract The relevant experiments and studies were conducted to address the metallurgical defects such as subcutaneous bubbles and slag inclusions occurring during the enamel steel continuous casting process. According to the high-temperature experimental results, calculations were made to determine the changes in viscosity and tension due to the steel reaction with the slag. Based on the experimental findings, there was a notable variation in the content of SiO2 and Al2O3 in the slag before and after the reaction. The concentration of the element Al in the steel melt significantly decreased, whereas the concentration of Ti showed a minimal change. These observations indicate that the reduction of SiO2 at the slag–steel interface is predominantly attributed to the role of Al. The calculation results showed that at 300 s of reaction time, the viscosity rapidly increased from 0.108 to 0.133 Pa·s and then slowly increased to 0.155 Pa·s; The interfacial tension rapidly decreased from its initial value of 1,380 mJ·m−2 to a minimum of 1,320 mJ·m−2, and it then slowly increased to an equilibrium state. Therefore, the main cause of the occurrence of porosity defects in the enamel steel continuous casting process is the reduction of interfacial tension between slag, steel, and gas caused by the reaction between the slag and steel, as well as the foaming of the slag.

Strong impact of exposure to water/solvent mixtures on permeance of nanofiltration membranes

Water/solvent mixtures released from industrial processes, especially in pharma and fine chemical synthesis or in advanced oil production, are an environmental concern, necessitating the development of efficient remediation and recycling techniques. Solvent-tolerant nanofiltration (STNF), situated between aqueous nanofiltration (NF) and solvent-resistant nanofiltration (SRNF), offers a promising solution. This study investigates the potential of using aqueous NF- and SRNF-membranes to treat water/solvent mixtures. Commercial membranes (NF270, DuraMem® 300, DuraMem® 200) and a lab-synthesized polyvinylidene fluoride (XL-PVDF NF) membrane were used to treat dimethyl sulfoxide (DMSO), acetonitrile (ACN), Isopropyl alcohol (IPA), or dimethylformamide (DMF) mixtures with water. The addition of 10% DMSO, ACN, IPA, or DMF to water significantly reduced the permeance of these NF-membranes, and an increase in temperature failed to restore the initial permeance. Changes in both viscosity and surface tension of the water/solvent solutions strongly influence the permeance of the NF-membranes. Flory-Huggins and Zimm-Lundberg theories offered an explanation for the phenomenon where solvent clusters form within the dense polymer matrix of NF-membranes upon exposure to water/solvent mixtures, resulting in decreased water permeabilities. NMR analysis identified of the presence of small amounts of solvents in the STNF-membranes, even still after prolonged exposure to pure water permeation. The results emphasize the current shortcomings of aqueous and solvent-resistant membrane chemistries in handling water/solvent mixtures. Minor solvent additions significantly modify NF membrane permeance, emphasizing the need for innovative material design, especially given the variable solvent content in industrial applications.

Extracellular acidification attenuates bronchial contraction via an autocrine activation of EP2 receptor: Its diminishment in murine experimental asthma

PurposeExtracellular acidification is a major component of tissue inflammation, including airway inflammation in asthmatics. However, its physiological/pathophysiological significance in bronchial function is not fully understood. Currently, the functional role of extracellular acidification on bronchial contraction was explored. MethodsLeft main bronchi were isolated from male BALB/c mice. Epithelium-removed tissues were exposed to acidic pH under submaximal contraction induced by 10−5 M acetylcholine in the presence or absence of a COX inhibitor indomethacin (10−6 M). Effects of AH6809 (10−6 M, an EP2 receptor antagonist), BW A868C (10−7 M, a DP receptor antagonist) and CAY10441 (3×10−6 M, an IP receptor antagonist) on the acidification-induced change in tension were determined. The release of prostaglandin E2 (PGE2) from epithelium-denuded tissues in response to acidic pH was assessed using an ELISA. ResultsIn the bronchi stimulated with acetylcholine, change in the extracellular pH from 7.4 to 6.8 caused a transient augmentation of contraction followed by a sustained relaxing response. The latter inhibitory response was abolished by indomethacin and AH6809 but not by BW A868C or CAY10441. Both indomethacin and AH6809 significantly increased potency and efficacy of acetylcholine at pH 6.8. Stimulation with low pH caused an increase in PGE2 release from epithelium-denuded bronchi. Interestingly, the acidic pH-induced bronchial relaxation was significantly reduced in a murine asthma model that had a bronchial hyperresponsiveness to acetylcholine. ConclusionTaken together, extracellular acidification could inhibit the bronchial contraction via autocrine activation of EP2 receptors. The diminished acidic pH-mediated inhibition of bronchial tone may contribute to excessive bronchoconstriction in inflamed airways such as asthma.

Charge Regulation at the Nanoscale as Evidenced from Light-Responsive Nanoemulsions.

Emulsions are indispensable in everyday life, and the demand for emulsions' diversity and control of properties is therefore substantial. As emulsions possess a high internal surface area, an understanding of the oil/water (o/w) interfaces at the molecular level is fundamental but often impaired by experimental limitations to probe emulsion interfaces in situ. Here, we have used light-responsive surfactants (butyl-AAP) that can photoisomerize between E and Z isomers by visible and UV light irradiation to tune the emulsion interfaces. This causes massive changes in the interface tension at the extended o/w interfaces in macroemulsions and a drastic shift in the surfactants' critical micelle concentration, which we show can be used to control both the stability and phase separation. Strikingly different from macroemulsions are nanoemulsions (RH ∼90 nm) as these are not susceptible to E/Z photoisomerization of the surfactants in terms of changes in their droplet size or ζ-potential. However, in situ second-harmonic scattering and pulsed-field gradient nuclear magnetic resonance (NMR) experiments show dramatic and reversible changes in the surface excess of surfactants at the nanoscopic interfaces. The apparent differences in ζ-potentials and surface excess provide evidence for a fixed charge to particle size ratio and the need for counterion condensation to renormalize the particle charge to a critical charge, which is markedly different compared to the behavior of very large particles in macroemulsions. Thus, our findings may have broader implications as the electrostatic stabilization of nanoparticles requires much lower surfactant concentrations, allowing for a more sustainable use of surfactants.

PTHrP attenuates spontaneous contractions in detrusor smooth muscle of the rat bladder by activating spontaneous transient outward potassium currents.

Parathyroid hormone-related protein (PTHrP) released from detrusor smooth muscle (DSM) cells upon bladder distension attenuates spontaneous phasic contractions (SPCs) in DSM and associated afferent firing to facilitate urine storage. Here, we investigate the mechanisms underlying PTHrP-induced inhibition of SPCs, focusing on large-conductance Ca2+-activated K+ channels (BK channels) that play a central role in stabilizing DSM excitability. Perforated patch-clamp techniques were applied to DSM cells of the rat bladder dispersed using collagenase. Isometric tension changes were recorded from DSM strips, while intracellular Ca2+ dynamics were visualized using Cal520AM-loaded DSM bundles. DSM cells developed spontaneous transient outward potassium currents (STOCs) arising from the opening of BK channels. PTHrP (10nM) increased the frequency of STOCs without affecting their amplitude at a holding potential of - 30mV but not - 40mV. PTHrP enlarged depolarization-induced, BK-mediated outward currents at membrane potentials positive to + 20mV in a manner sensitive to iberiotoxin (100nM), the BK channel blocker. The PTHrP-induced increases in BK currents were also prevented by inhibitors of sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) (CPA 10µM), L-type voltage-dependent Ca2+ channel (LVDCC) (nifedipine 3µM) or adenylyl cyclase (SQ22536 100µM). PTHrP had no effect on depolarization-induced LVDCC currents. PTHrP suppressed and slowed SPCs in an iberiotoxin (100nM)-sensitive manner. PTHrP also reduced the number of Ca2+ spikes during each burst of spontaneous Ca2+ transients. In conclusion, PTHrP accelerates STOCs discharge presumably by facilitating SR Ca2+ release which prematurely terminates Ca2+ transient bursts resulting in the attenuation of SPCs.

Biodegradation capabilities of filamentous fungi in high-concentration heavy crude oil environments.

In this comprehensive study, we delved into the capabilities of five fungal strains: Aspergillus flavus, Aspergillus niger, Penicillium chrysogenum, Penicillium glabrum, and Penicillium rubens (the latter isolated from heavy crude oil [HCO]) in metabolizing HCO as a carbon source. Employing a meticulously designed experimental approach, conducted at room temperature (25°C), we systematically explored various culture media and incubation periods. The results unveiled the exceptional resilience of all these fungi to HCO, with A. flavus standing out as the top performer. Notably, A. flavus exhibited robust growth, achieving a remarkable 59.1% expansion across the medium's surface, accompanied by distinctive macroscopic traits, including a cottony appearance and vibrant coloration. In an effort to further scrutinize its biotransformation prowess, we conducted experiments in a liquid medium, quantifying CO2 production through gas chromatography, which reached its zenith at day30, signifying substantial bioconversion with a 38% increase in CO2 production. Additionally, we monitored changes in surface tension using the Du Noüy ring method, revealing a reduction in aqueous phase tension from 72.3 to 47mN/m. This compelling evidence confirms that A. flavus adeptly metabolizes HCO to fuel its growth, while concurrently generating valuable biosurfactants. These findings underscore the immense biotechnological potential of A. flavus in addressing challenges related to HCO, thereby offering promising prospects for bioremediation and crude oil bioupgrading endeavors.

Biological characteristics of mechanosensitive channels MscS and MscL in Actinobacillus pleuropneumoniae.

Actinobacillus pleuropneumoniae is an important respiratory pathogen that can cause porcine contagious pleuropneumonia (PCP), resulting in significant economic losses in swine industry. Microorganisms are subjected to drastic changes in environmental osmolarity. In order to alleviate the drastic rise or fall of osmolarity, cells activate mechanosensitive channels MscL and MscS through tension changes. MscL not only regulates osmotic pressure but also has been reported to secrete protein and uptake aminoglycoside antibiotic. However, MscL and MscS, as the most common mechanosensitive channels, have not been characterized in A. pleuropneumoniae. In this study, the osmotic shock assay showed that MscL increased sodium adaptation by regulating cell length. The results of MIC showed that deletion of mscL decreased the sensitivity of A. pleuropneumoniae to multiple antibiotics, while deletion of mscS rendered A. pleuropneumoniae hypersensitive to penicillin. Biofilm assay demonstrated that MscL contributed the biofilm formation but MscS did not. The results of animal assay showed that MscL and MscS did not affect virulence in vivo. In conclusion, MscL is essential for sodium hyperosmotic tolerance, biofilm formation, and resistance to chloramphenicol, erythromycin, penicillin, and oxacillin. On the other hand, MscS is only involved in oxacillin resistance.IMPORTANCEBacterial resistance to the external environment is a critical function that ensures the normal growth of bacteria. MscL and MscS play crucial roles in responding to changes in both external and internal environments. However, the function of MscL and MscS in Actinobacillus pleuropneumoniae has not yet been reported. Our study shows that MscL plays a significant role in osmotic adaptation, antibiotic resistance, and biofilm formation of A. pleuropneumoniae, while MscS only plays a role in antibiotic resistance. Our findings provide new insights into the functional characteristics of MscL and MscS in A. pleuropneumoniae. MscL and MscS play a role in antibiotic resistance and contribute to the development of antibiotics for A. pleuropneumoniae.

Abdominal Wall Tension and Early Outcomes after Posterior Component Separation with Transversus Abdominis Release: Does a "Tension-Free" Closure Really Matter?

Ventral hernias result in fibrosis of the lateral abdominal wall muscles, increasing tension on fascial closure. Little is known about the effect of abdominal wall tension on outcomes after abdominal wall reconstruction. We aimed to identify an association between abdominal wall tension and early postoperative outcomes in patients who underwent posterior component separation (PCS) with transversus abdominis release (TAR). Using a proprietary, sterilizable tensiometer, the tension needed to bring the anterior fascial elements to the midline of the abdominal wall during PCS with TAR was recorded. Tensiometer measurements, in pounds (lb), were calibrated by accounting for the acceleration of Earth's gravity. Baseline fascial tension, change in fascial tension, and fascial tension at closure were evaluated with respect to 30-day outcomes, including wound morbidity, hospital readmission, reoperation, ileus, bleeding, and pulmonary complications. A total of 100 patients underwent bilateral abdominal wall tensiometry, for a total of 200 measurements (left and right side for each patient). Mean baseline anterior fascial tension was 6.78 lb (SD 4.55) on each side. At abdominal closure, the mean anterior fascial tension was 3.12 (SD 3.21) lb on each side. Baseline fascial tension and fascial tension after PCS with TAR at abdominal closure were not associated with surgical site infection, surgical site occurrence, readmission, ileus, and bleeding requiring transfusion. The event rates for all other complications were too infrequent for statistical analysis. Baseline and residual fascial tension of the anterior abdominal wall do not correlate with early postoperative morbidity in patients undergoing PCS with TAR. Further work is needed to determine if abdominal wall tension in this context is associated with long-term outcomes, such as hernia recurrence.

Does Magnetic Field Influence the Surface Tension of Ferrofluid?

Studying the physical properties of ferrofluids is a challenging task, especially when conventional experimental techniques are adapted to the presence of a magnetic field. To date, there has been no definitive understanding of how the magnetic field affects the surface energy of ferrofluid interfaces. In this study, we perform a direct experimental investigation to assess the effect of magnetic fields on the surface tension of ferrofluids. For this purpose, a modified capillary wave technique was modified for use in the presence of an external magnetic field. A decrease in the wavelength of the capillary wave was observed when the magnetic field was oriented perpendicular to the ferrofluid surface, and an increase was recorded when the magnetic field was parallel. We note that the capillary wave pattern elongates along the magnetic field force lines. The observed effect is attributed to the varying influence of the magnetic field along and across the propagating capillary wave. Analysis of the dispersion relation and evaluation of the impacts of various mechanisms influencing capillary waves revealed, that the changes in the surface tension of ferrofluids in the presence of a magnetic field are responsible for the observed behavior. It is shown that the surface tension of the MK 8-40 ferrofluid gradually increases with the applied magnetic field and reaches a grouth up to 10% in a magnetic field of ∼10 kA/m. Thus, the surface tension is found to be influenced by an external magnetic field.

The Role of Hypoxia Inducible Factor (HIF) 1α in the Pathogenesis of Liver Cirrhosis: A Narrative Literature Review

The small changes in oxygen tension that occur during viral hepatitis, metabolic disorders, steatohepatitis, inflammation, and carcinogenesis are sufficient to increase hypoxic response, namely an increase in HIF. HIF is a protein that belongs to the PAS (period circadian protein-aryl hydrocarbon receptor nuclear translocator-single-minded protein) family. HIF regulates the adaptation of cells to oxygen. HIF is a transcription factor containing α and β subunits. The expression of the α subunit is oxygen-dependent, while the β subunit is expressed continuously and independently of oxygen. HIFs regulate various signaling events by binding to specific DNA sequences known as hypoxia response elements (HREs) in target genes, leading to an increase or decrease in their transcription. HIF-1α is a key regulator of hypoxia signaling.

'Hearts' and 'minds': Illustrating identity tensions of people living and working through marketising policy change of allied health disability services in Australia.

Service-based caring sectors like disability are increasingly being operated via market logic, including shifts towards personalised funding. These shifts must be brought to life in/through people already located in relation to ideas and values that underpin historical policies. Our manuscript examines how identities are re/shaped in relation to marketised policy change and explores how identity change unfolds (or not) during periods of transition: situated within the transition to the National Disability Insurance Scheme executed in Australia as a major disability funding reform. Our qualitative dataset involves interview and focus group data collected with service recipients/carers (n = 28), providers/managers (n = 17) and advocates (n = 2) during shift from government- to personally-controlled funding of allied health services for people with disability in Australia (2017-2020). We used layered sociological inference to develop and interrogate processes of tension and identity change amidst lived experience(s) of policy change. Our analysis elucidates how various identities were encouraged, desired, resisted and constrained in relation to the policy transition. We bring together sub-themes from analysis of recipient/carer data (getting value-for-money; critiquing service quality; and experiencing system shortfalls) and manager/provider data (learning to transact; the call to care; and structural frictions in/and identity transitions) to interpret that recipients/carers are Feeling (like) the dollar sign and that managers/providers are Troubling profits. In both cases 'hearts' and 'minds' are perceived to be diametrically opposed and symbolic in/against processes of marketisation. We synthesise our data into an illustrative framework that facilitates understanding of how this perception of opposed 'hearts' and 'minds' seems to constrain the identity transitions encouraged by personalised funding, and explore ways in which desired identities might be supported amidst marketising policy transition.

How plants sense and respond to osmotic stress.

Drought is one of the most serious abiotic stresses to land plants. Plants sense and respond to drought stress to survive under water deficiency. Scientists have studied how plants sense drought stress, or osmotic stress caused by drought, ever since Charles Darwin, and gradually obtained clues about osmotic stress sensing and signaling in plants. Osmotic stress is a physical stimulus that triggers many physiological changes at the cellular level, including changes in turgor, cell wall stiffness and integrity, membrane tension, and cell fluid volume, and plants may sense some of these stimuli and trigger downstream responses. In this review, we emphasized water potential and movements in organisms, compared putative signal inputs in cell wall-containing and cell wall-free organisms, prospected how plants sense changes in turgor, membrane tension, and cell fluid volume under osmotic stress according to advances in plants, animals, yeasts, and bacteria, summarized multilevel biochemical and physiological signal outputs, such as plasma membrane nanodomain formation, membrane water permeability, root hydrotropism, root halotropism, Casparian strip and suberin lamellae, and finally proposed a hypothesis that osmotic stress responses are likely to be a cocktail of signaling mediated by multiple osmosensors. We also discussed the core scientific questions, provided perspective about the future directions in this field, and highlighted the importance of robust and smart root systems and efficient source-sink allocations for generating future high-yield stress-resistant crops and plants.

Number of intra-operative cyclic knee motion required to achieve stable graft tension in anterior cruciate ligament reconstruction; a prospective clinical study.

Applying pretension by cyclic knee motion immediately before graft fixation in anterior cruciate ligament (ACL) reconstruction surgery decreases graft elongation during the postoperative course. However, the expected change in graft tension caused by cyclic knee motion remains unclear. We measured graft tension changes caused by cyclic knee motion during double-bundle ACL reconstruction. We included 39 patients undergoing primary anatomical double-bundle ACL reconstruction with autologous hamstrings as graft sources, at multiple centers between February 2021 and August 2022. After securing the anteromedial (AM) and posterolateral (PL) bundle grafts to the femoral cortex, they were initially tensioned to 40 N per bundle. After 10 cycles of knee extension and flexion motion, ranging from 0 to 90-110°, tension was re-measured and re-tensioned to 40 N if the graft tension had decreased. This was repeated thrice for 10 cycles on each graft. Every 10 cycles, we recorded graft tension changes (ΔGT) and compared the mean ΔGT in the AM and PL bundles. Furthermore, we assessed relationships between total ΔGT in each bundle, age, sex, and graft diameter. Twenty-five women and 14 men with a mean age of 27.4 ± 12.4 years were included. The mean ΔGT in AM and PL bundles after every 10 cycles were 6.6 ± 3.7 N, 3.0 ± 2.3 N, 1.4 ± 1.5 N, and 9.9 ± 3.8 N, 4.9 ± 2.6 N, and 2.5 ± 1.9 N, respectively. There were significant differences in ΔGT in both bundles after every 10 cycles (p < 0.01). ΔGT in the AM bundle was significantly lower than in the PM bundle at the same number of cycles (p < 0.01). No correlation was observed between ΔGT in either bundle and age, sex, or graft diameter. The initially applied graft tension decreased by intra-operative cyclic knee movement, and the changes in graft tension decreased after retention and repeated cycles. Three sets of 10 cycles knee motion may avoid initial tension loss of the hamstring autograft in the early phase after double-bundle ACL reconstruction.

Solubility of CO2 in salty water: adsorption, interfacial tension and salting out effect

In this work, we performed Molecular Dynamics simulations to investigate the solubility of CO 2 in both pure water and NaCl aqueous solutions, employing various force fields for water and NaCl. We first focussed on the solubility of CO 2 in TIP4P/2005 and TIP4P/Ice water models. We found that it was necessary to apply positive deviations to the energetic Lorentz-Berthelot combining rules for the cross interactions of water and CO 2 in both models to accurately replicate the experimental solubility of the gas. Then we found a negative adsorption of ions at the NaCl solution– CO 2 interface. We also observed an increase of the interfacial tensions of the system when adding salt which is related with the observed negative adsorption of the ions at the interface. Furthermore, we found that unit charge models tend to highly overestimate the change in the interfacial tension compared to scaled charge models. Finally, we also explored the salting out effect of CO 2 using different force fields for NaCl. Our findings indicate that unit charge force fields significantly overestimate the salting out effect of CO 2 while the scaled charge model Madrid-2019 accurately reproduces the experimental salting out effect of CO 2 in NaCl solutions.

Displacement of the selvage of the fabric on shuttless looms as a factor in optimizing the silk fabric production process

One of the main weaving defects that reduces the quality of solid fabrics is streaks that appear after stopping the machine. These bands differ from shortcuts in that they only form when the machine is put into operation. The reason for the formation of boot bands can be due to the characteristics of both the elastic feeding system and the design of the main machine parts involved in the fabric formation process: batons, waste, feeding devices material for the machine with the base. and discard the finished fabric. On textile machines, for ease of maintenance, the machines are stopped and started in a stagnant position, and with each subsequent start of the machine, the baton and together with the reed do not have time to gain inertial force. that they have when the machine is running. As a result, the strength of the reed waves may not be enough, leading to the formation of shear lines (release strips). The main controller of a nonclosing loom does not control the tension of the sole after stopping the machine. Warp tension due to warp yarn slackening and fabric changes, resulting in a change in tension at the first pass. On a weaving machine, the elastic fabric forming system (ESFF) consists of two heterogeneous warp and fabric systems, with different stretch characteristics, and when the weaving machine is stopped, the relative lengths of the warp and fabric as well as the total The tension of the elastic system changes the formation of the fabric. In this case, the total length of the elastic tissue formation system does not change.