Recovery Of Activity Research Articles

Granulocyte colony-stimulating factor effects on neurological and motor function in animals with spinal cord injury: a systematic review and meta-analysis.

Spinal cord injury (SCI) is a severe neurological injury for which no effective treatment exists. Granulocyte colony-stimulating factor (G-CSF) is used to treat autologous bone marrow transplantation, chemotherapy-induced granulocytopenia, Acquired Immune Deficiency Syndrome (AIDS), etc. Recent research has revealed the potential application of G-CSF on neuroprotective effectiveness. In central nervous system diseases, G-CSF can be used to alleviate neuronal injury. To investigate the effects of G-CSF on Basso, Beattie, and Bresnahan (BBB) scale score, inclined plane test, electrophysiologic exam, quantitative analysis of TUNEL-positive cells, and quantitative analysis of glial fibrillary acidic protein (GFAP) immunostaining images in animal models of SCI. We searched PubMed, Web of Science, and Embase databases for all articles on G-CSF intervention with animal models of SCI reported before November 2022. A total of 20 studies met the inclusion criteria. Results revealed that G-CSF intervention could improve the BBB scale score in both groups at 3, 7, 14, 28, and 35 days [at 35 days, weighted mean differences (WMD) = 2.4, 95% CI: 1.92-2.87, p < 0.00001, I2 = 69%]; inclined plane test score; electrophysiologic exam; quantitative analysis of TUNEL-positive cell numbers; quantitative analysis of GFAP immunostaining images in animal models of SCI. Subgroup analysis revealed that treatment with normal saline, phosphate-buffered saline, and no treatment resulted in significantly different neurological function effectiveness compared to the G-CSF therapy. SD rats and Wistar rats with SCI resulted in significant neurological function effectiveness. C57BL/6 mice showed no difference in the final effect. The T9-T10 or T10 segment injury model and the T8-T9 or T9 segment injury model resulted in significant neurological function effectiveness. The BBB score data showed no clear funnel plot asymmetry. We found no bias in the analysis result (Egger's test, p = 0.42). In our network meta-analysis, the SUCRA ranking showed that 15 mg/kg-20 mg/kg was an optimal dose for long-term efficacy. Our meta-analysis suggests that G-CSF therapy may enhance the recovery of motor activity and have a specific neuroprotective effect in SCI animal models.Systematic review registration: PROSPERO, identifier: CRD42023388315.

Optimisation of soybean oil enriched with lipophilic antioxidants from Thai rice germs and their nanoparticles developed using complex coacervation

Soybean oil contains high levels of polyunsaturated fatty acids, which are susceptible to lipid oxidation, negatively affecting on the stability of food products and human health. In this study, soybean oil was enriched with lipophilic antioxidants from various types of Thai rice germs with broken rice pieces. The ultrasonic-assisted extraction was optimised using response surface methodology. Under temperature of 40 °C, time of 40 min, and solvent-sample ratio of 5, the oils with high vitamin E and γ-oryzanol contents were achieved. Complex coacervation was applied to develop oil-loaded nanoparticles using soy protein isolate (SPI) and inulin as wall materials. The size of the obtained particles ranged from 170 to 240 nm, with an irregular continuous surface. FTIR spectra revealed electrostatic interactions between SPI and inulin. Moreover, the nanoparticles exhibited a greater release of lipophilic antioxidants and higher recovery of antioxidant activity than the unencapsulated oils.

Ultrasound as the main method for diagnosing peripheral nerve injuries in mine blast trauma

BACKGROUND: The amount of published data related to peripheral nerve blast injuries is limited.&#x0D; AIM: The study was aimed at determining the accuracy and sensitivity and assessing the specificity of ultrasound in the diagnosis of peripheral nerve injuries in mine blast trauma.&#x0D; METHODS: A total of 159 patients (274 peripheral nerves) were examined. Ultrasound was performed according to the standard technique using a HI VISION Avius HITACHI scanner with an EUP-L74M linear transducer (a frequency range of 513 MHz) and a preset musculoskeletal system ultrasound program. The duration of nerve injuries ranged from 2 to 273 days. All patients were men aged 20 to 48 years. Peripheral nerves were damaged as a result of mine blast trauma. Statistical analysis was used to assess sensitivity, specificity, and diagnostic accuracy. These characteristics were calculated according to the qualitative assessment of surgical intervention, the results of conservative treatment, and the method under study (ultrasound).&#x0D; RESULTS: A total of 274 damaged peripheral nerves were examined. The Group 1 included 93 (34%) nerves that required surgical intervention. In Group 2, consisting of 181 (66%) nerves, conservative treatment was used. Most of the nerves (47 [51%]) in Group 1 were damaged due to the compression effects of scarring in the surrounding tissues. Seventeen (18%) partial violations of the anatomical integrity of nerves with the formation of intramural and marginal neuromas were detected. Multiple and single nerve injuries were observed in 95 (59.7%) and 64 people (40.3%), respectively. Peripheral nerves of the upper extremities were damaged more frequently (185 [67.5%]), whereas nerves of the lower extremities were damaged in 89 (32.5%) cases. Ultrasound showed an increase in the cross-sectional area of nerves, blurred contours, decreased echogenicity, and changes in the bundle structure up to the complete absence of differentiation of individual fascioculi. The formation of neuromas was observed in complete and partial nerve ruptures. All 93 nerves in Group 1 underwent surgical intervention, particularly, external neurolysis (32 [34%]), internal neurolysis (15 [16%]), nerve suture (15 [16%]), excision of neuroma followed by microsurgical epineural suture (18 [19%]), and autoneural plasty (11 [12%]). In 2 (3%) cases, a decision was made to abstain from plasty and perform a tendon transposition due to a pronounced diastasis. All patients of Group 2 were shown to have a wait-and-see approach, and conservative therapy was prescribed. In 179 (99%) cases, complete recovery of sensory and motor activity was observed within 21 days. In 2 (1%) patients, a repeated ultrasound was performed due to no effect of treatment. Compression by scar tissues was revealed, and surgical intervention was made.&#x0D; CONCLUSIONS: In mine-explosive impact, ultrasound is the leading method for diagnosing peripheral nerve injuries. Ultrasound with sensitivity of 97.8% and specificity of 98.8% reveals lesions for which surgical treatment is indicated. The diagnostic accuracy is 98.5%.

5-Aminolevulinic acid bypasses mitochondrial complex I deficiency and corrects physiological dysfunctions in Drosophila.

Complex I (CI) deficiency in mitochondrial oxidative phosphorylation (OXPHOS) is the most common cause of mitochondrial diseases, and limited evidence-based treatment options exist. Although CI provides the most electrons to OXPHOS, complex II (CII) is another entry point of electrons. Enhancement of this pathway may compensate for a loss of CI; however, the effects of boosting CII activity on CI deficiency are unclear at the animal level. 5-Aminolevulinic acid (5-ALA) is a crucial precursor of heme, which is essential for CII, complex III, complex IV (CIV) and cytochrome c activities. Here, we show that feeding a combination of 5-ALA hydrochloride and sodium ferrous citrate (5-ALA-HCl + SFC) increases ATP production and suppresses defective phenotypes in Drosophila with CI deficiency. Knockdown of sicily, a Drosophila homolog of the critical CI assembly protein NDUFAF6, caused CI deficiency, accumulation of lactate and pyruvate and detrimental phenotypes such as abnormal neuromuscular junction development, locomotor dysfunctions and premature death. 5-ALA-HCl + SFC feeding increased ATP levels without recovery of CI activity. The activities of CII and CIV were upregulated, and accumulation of lactate and pyruvate was suppressed. 5-ALA-HCl + SFC feeding improved neuromuscular junction development and locomotor functions in sicily-knockdown flies. These results suggest that 5-ALA-HCl + SFC shifts metabolic programs to cope with CI deficiency. Bullet outline 5-Aminolevulinic acid (5-ALA-HCl + SFC) increases ATP production in flies with complex I deficiency.5-ALA-HCl + SFC increases the activities of complexes II and IV.5-ALA-HCl + SFC corrects metabolic abnormalities and suppresses the detrimental phenotypes caused by complex I deficiency.

Multi-mode switching control of electromagnetic hybrid suspension based on human subjective sensation

This study proposes a multi-mode switching control strategy based on electromagnetic hybrid suspension (EMHS) to achieve the best relationship possible between the vehicle’s vibration reduction performance and energy consumption. The working modes of EMHS are divided into active, semi-active, and energy recovery modes according to the relationship between the root mean square of weighted acceleration and the human subjective sensation. The two key switching parameters of the analysis sampling interval and switching judgment times are introduced to optimize the switching conditions and reduce the deterioration of comfort and handling stability caused by frequent system switching in mode switching decisions. In the sub-modes, it’s designed that an LQG main control loop uses an ant colony algorithm to optimize parameters to obtain the ideal output force. And inner-loop control strategies in active and semi-active modes are designed so that the actual force output by the actuator tracks the ideal force. The results show that the multi-mode switching control strategy can switch the EMHS reasonably in the three modes and achieve good vibration reduction performance. The RMS of SMA, SDD, and TDL are reduced by 27.5%, 6.3%, and 17.6%, respectively under the variable conditions road.

Adsorption–precipitation–cross-linking immobilization of GDSL-type esterase from Aspergillus niger GZUF36 by polydopamine-modified magnetic clarity tetroxide nanocouplings and its enzymatic characterization

Recombinant INANE1 (rINANE1), a recombinant intracellular GDSL-type esterase from Aspergillus niger GZUF36, has high acetate substrate specificity. Here, rINANE1 was successfully immobilized on polydopamine (PDA)-modified magnetic ferric oxide nanoparticles (Fe3O4NPs) by adsorption–precipitation–cross-linking to obtain cross-linked enzyme aggregate (CLEA)–rINANE1–Fe3O4@PDA. Fe3O4, Fe3O4@PDA, and CLEA–rINANE1–Fe3O4@PDA were characterized by scanning electron microscopy, X-ray diffraction, vibrating-sample magnetometry, Fourier transform infrared (FTIR) spectroscopy, and zeta potential analysis. Upon immobilization, CLEA–rINANE1–Fe3O4@PDA, with a protein loading of 72.72 ± 1.01 mg/g, reached optimal activity recovery of 104.40 % ± 1.14 %. FTIR analysis showed that immobilization increased the relative content of β-folding in rINANE1 by 12.25 % and reduced irregular curl by 4.16 %, rendering the structure more orderly. Specifically, under an alkaline condition (pH 10), CLEA–rINANE1–Fe3O4@PDA performed over 100 % of initial activity. The optimum temperature increased by 5 °C, and over 55 % of the initial activity was observed after 12 h at 55 °C. CLEA–rINANE1–Fe3O4@PDA showed over 40 % of its relative activity, whereas free rINANE1 showed <10 % in acetonitrile. In addition, the relative activity of CLEA–rINANE1–Fe3O4@PDA was retained at about 80 % after eight cycles and maintained at 109 % after 45 days. The PDA-modified magnetic ferrite nanoparticles exhibited excellent stability and recyclability, providing a new avenue for developing industrial biocatalysts.

PH Meter-Assisted Biosensor Based on Glucose Oxidase-Conjugated Magnetic Metal-Organic Framework for On-Site Evaluation of Bacterial Contamination.

There remains a critical need for the detection of bacterial contamination to ensure public health. In this work, we developed a pH meter-assisted biosensor based on glucose oxidase (GOx)-conjugated magnetic zeolitic imidazolate framework-8 (mZIF-8) for on-site evaluation of bacterial contamination. The mZIF-8/GOx conjugate was produced from the electrostatic interaction between GOx and mZIF-8 and was demonstrated to inhibit GOx activity without protein denaturation. However, the presence of bacteria can cause the release of GOx from the mZIF-8 surface through competitive binding with mZIF-8, resulting in the recovery of GOx activity, which converts glucose into gluconic acid and provides an amplified pH signal. This finding allows the mZIF-8/GOx conjugate to be a biosensor for on-site detection of bacterial contamination with a pH meter as a readout. Benefiting from the magnetic separation property of mZIF-8, greatly enhanced sensitivity and precision have been achieved with detection limits of 10 cfu/mL for Escherichia coli and 30 cfu/mL for Staphylococcus aureus. Meanwhile, the flexibility of this biosensor was validated by quantitative analysis of mixed bacteria including Gram-positive and Gram-negative bacteria with desired performances. The accurate bacterial determination in contaminated drinking water samples demonstrates the applicability of this biosensor for reliable home monitoring of water quality.

Lower limb suspension induces threshold-specific alterations of motor units properties that are reversed by active recovery

PurposeThis study aimed to non-invasively test the hypothesis that (a) short-term lower limb unloading would induce changes in the neural control of force production (based on motor units (MUs) properties) in the vastus lateralis muscle and (b) possible changes are reversed by active recovery (AR). MethodsTen young males underwent 10 days of unilateral lower limb suspension (ULLS) followed by 21 days of AR. During ULLS, participants walked exclusively on crutches with the dominant leg suspended in a slightly flexed position (15°–20°) and with the contralateral foot raised by an elevated shoe. The AR was based on resistance exercise (leg press and leg extension) and executed at 70% of each participant's 1 repetition maximum, 3 times/week. Maximal voluntary isometric contraction (MVC) of knee extensors and MUs properties of the vastus lateralis muscle were measured at baseline, after ULLS, and after AR. MUs were identified using high-density electromyography during trapezoidal isometric contractions at 10%, 25%, and 50% of the current MVC, and individual MUs were tracked across the 3 data collection points. ResultsWe identified 1428 unique MUs, and 270 of them (18.9%) were accurately tracked. After ULLS, MVC decreased by 29.77%, MUs absolute recruitment/derecruitment thresholds were reduced at all contraction intensities (with changes between the 2 variables strongly correlated), while discharge rate was reduced at 10% and 25% but not at 50% MVC. Impaired MVC and MUs properties fully recovered to baseline levels after AR. Similar changes were observed in the pool of total as well as tracked MUs. ConclusionOur novel results demonstrate, non-invasively, that 10 days of ULLS affected neural control predominantly by altering the discharge rate of lower-threshold but not of higher-threshold MUs, suggesting a preferential impact of disuse on motoneurons with a lower depolarization threshold. However, after 21 days of AR, the impaired MUs properties were fully restored to baseline levels, highlighting the plasticity of the components involved in neural control.

Activity recovery for differently shaped objects in quantitative SPECT

Objective. The aim was to theoretically and experimentally investigate recovery in SPECT images with objects of different shapes. Furthermore, the accuracy of volume estimation by thresholding was studied for those shapes. Approach. Nine spheres, nine oblate spheroids, and nine prolate spheroids phantom inserts were used, of which the six smaller spheres were part of the NEMA IEC body phantom and the rest of the inserts were 3D-printed. The inserts were filled with 99mTc and 177Lu. When filled with 99mTc, SPECT images were acquired in a Siemens Symbia Intevo Bold gamma camera and when filled with 177Lu in a General Electric NM/CT 870 DR gamma camera. The signal rate per activity (SRPA) was determined for all inserts and represented as a function of the volume-to-surface ratio and of the volume-equivalent radius using VOIs defined according to the sphere dimensions and VOIs defined using thresholding. Experimental values were compared with theoretical curves obtained analytically (spheres) or numerically (spheroids), starting from the convolution of a source distribution with a point-spread function. Validation of the activity estimation strategy was performed using four 3D-printed ellipsoids. Lastly, the threshold values necessary to determine the volume of each insert were obtained. Main results. Results showed that SRPA values for the oblate spheroids diverted from the other inserts, when SRPA were represented as a function of the volume-equivalent radius. However, SRPA values for all inserts followed a similar behaviour when represented as a function of the volume-to-surface ratio. Results for ellipsoids were in agreement with those results. For the three types of inserts the volume could be accurately estimated using a threshold method for volumes larger than 25 ml. Significance. Determination of SRPA independently of lesion or organ shape should decrease uncertainties in estimated activities and thereby, in the long term, be beneficial to patient care.

Unraveling the pathophysiology of lower-limb postthrombotic syndrome in adolescents: a proof-of-concept study.

A better understanding of the pathophysiology of pediatric postthrombotic syndrome (PTS) is needed to develop strategies to treat this condition. We investigated calf pump function, exercise capacity, balance in power output, and changes in limb muscle oxygen saturation (SmO2) and fluid content during exercise in 10 pediatric patients with unilateral lower-limb PTS, and in age- and sex-matched controls (1:1-1:2 ratio). Outcomes were investigated usingbioimpedance spectroscopy, torque-sensing pedals, and near-infrared spectroscopy during incremental- and constant-load cycling tests. The median age at participation was 17years (25th-75th percentile, 15-18 years); 68% of participants were females. The median CAPTSure score in the affected leg of affected participants was 35 points (25th-75th percentile, 24-46 points), indicating moderate/severe PTS; 20% of patients had a history of central venous catheter-related thrombosis. Increasing PTS severity was associated with higher calf pump venous volume and higher ejection volume, leading to compensated calf pump performance. We found no evidence of PTS impact on exercise capacity. Leg contribution to power output was similar in affected and unaffected legs. However, the PTS-affected legs showed lower SmO2 during active cycling and recovery with increasing PTS severity, indicating impaired microvascular function in the muscle. These findings suggest that PTS severity is associated with impaired blood flow, presumably from elevated venous pressure during and after exercise. The fact that microvascular function is impaired in young patients with PTS underscores the relevance of developing strategies to mitigate the effects of this chronic vascular disease to minimize its deleterious effects as children grow older.

REGIONAL AND LOCAL SYSTEMS OF METHANE GAS DISTRIBUTION IN THE COAL-BEARING MASSIFS OF THE DONETS BASIN

Determining the regional and local peculiarities of methane gas distribution in the coal-bearing massifs of the Donets basin will help solve several important problems at once: creating safe conditions for mining operations, using methane as an alternative fuel, and improving the environmental situation in technologically loaded regions. Local gas-saturated systems of coal-rock massifs combining individual coal seams and their host rocks are primarily the result of accumulation and minimal impact of the following geodynamic processes. Important characteristics of rocks and coal as natural gas reservoirs are porosity and gas permeability. Changes in the initial indicators of coal substance indicate a deep transformation that coal seams undergo under fluid dynamic impact, which is determined by regional and local changes in the coal-bearing massifs of the basin.&#x0D; Gas content and gas migration in different strata of coal-bearing massifs are related by age and quality characteristics. The qualitative characteristics of the gas mixture of coal deposits are constantly changing along the section and dip of the seam and are particularly distinct in tectonically disturbed areas of coal massifs. All components of the gas mixture of coal seams are controlled by a mosaic of physical parameters of its various parts, both in the undisturbed and in the mined massif. Structural, shielded deposits are often found in relatively undisturbed mine massifs and can be developed as a local gas field. Depending on the condition of the coal and gas reservoir, the gas component can vary widely. During active maximum gas recovery, a large amount of heavy and unsaturated hydrocarbons rise in the workings, which can provoke gas-dynamic phenomena.&#x0D; On the basis of isotopic and geochemical studies of gas mixtures of coal-rock massifs, the polygenetic composition of natural gas in coal-bearing strata of the Ukrainian coal basins is substantiated and proved.

Validation of a new model of selective antegrade cerebral perfusion with circulatory arrest in rats.

Selective antegrade cerebral perfusion (SACP) is adopted as an alternative to deep hypothermic circulatory arrest (DHCA) during aortic arch surgery. However, there is still no preclinical evidence to support the use of SACP associated with moderate hypothermia (28-30°C) instead of DHCA (18-20°C). The present study aims to develop a reliable and reproducible preclinical model of cardiopulmonary bypass (CPB) with SACP applicable for assessing the best temperature management. A central cannulation through the right jugular vein and the left carotid artery was performed, and CPB was instituted.Animals were randomized into two groups: normothermic circulatory arrest without or with cerebral perfusion (NCA vs SACP). EEG monitoring was maintained during CPB. After 10min of circulatory arrest, rats underwent 60min of reperfusion. After that, animals were sacrificed, and brains were collected for histology and molecular biology analysis. Power spectral analysis of the EEG signal showed decreased activity in both cortical regions and lateral thalamus in all rats during the circulatory arrest. Only SACP determined complete recovery of brain activity and higher power spectral signal compared to NCA (p < 0.05). Histological damage scores and western blot analysis of inflammatory and apoptotic proteins like caspase-3 and Poly-ADP ribose polymerase (PARP) were significantly lower in SACP compared to NCA. Vascular endothelial growth factor (VEGF) and RNA binding protein 3 (RBM3) involved in cell-protection mechanisms were higher in SACP, showing better neuroprotection (p < 0.05). SACP by cannulation of the left carotid artery guarantees good perfusion of the whole brain in this rat model of CPB with circulatory arrest. The present model of SACP is reliable, repeatable, and not expensive, and it could be used in the future to achieve preclinical evidence for the best temperature management and to define the best cerebral protection strategy during circulatory arrest.

Active recovery vs hot- or cold-water immersion for repeated sprint ability after a strenuous exercise training session in elite skaters

ABSTRACT This study compared the acute effects of three recovery methods: active recovery (AR), hot- and cold-water immersion (HWI and CWI, respectively), used between two training sessions in elite athletes. Twelve national-team skaters (7 males, 5 females) completed three trials according to a randomized cross-over study. Fifteen minutes after an exhaustive ice-skating training session, participants underwent 20 min of HWI (41.1 ± 0.5°C), 15 min of CWI (12.1 ± 0.7°C) or 15 min of active recovery (AR). After 1 h 30 min of the first exercise, they performed a repeated-sprint cycling session. Average power output was slightly but significantly higher for AR (767 ± 179 W) and HWI (766 ± 170 W) compared to CWI (738 ± 156 W) (p = 0.026, d = 0.18). No statistical difference was observed between the conditions for both lactatemia and rating of perceived exertion. Furthermore, no significant effect of recovery was observed on the fatigue index calculated from the repeated sprint cycling exercises (p > 0.05). Finally, a positive correlation was found between the average muscle temperature measured during the recoveries and the maximal power output obtained during cycling exercises. In conclusion, the use of CWI in between high-intensity training sessions could slightly impair the performance outcomes compared to AR and HWI. However, studies with larger samples are needed to confirm these results, especially in less trained athletes.

Spinal neuromodulation mitigates myocardial ischemia-induced sympathoexcitation by suppressing the intermediolateral nucleus hyperactivity and spinal neural synchrony.

Myocardial ischemia disrupts the cardio-spinal neural network that controls the cardiac sympathetic preganglionic neurons, leading to sympathoexcitation and ventricular tachyarrhythmias (VTs). Spinal cord stimulation (SCS) is capable of suppressing the sympathoexcitation caused by myocardial ischemia. However, how SCS modulates the spinal neural network is not fully known. In this pre-clinical study, we investigated the impact of SCS on the spinal neural network in mitigating myocardial ischemia-induced sympathoexcitation and arrhythmogenicity. Ten Yorkshire pigs with left circumflex coronary artery (LCX) occlusion-induced chronic myocardial infarction (MI) were anesthetized and underwent laminectomy and a sternotomy at 4-5 weeks post-MI. The activation recovery interval (ARI) and dispersion of repolarization (DOR) were analyzed to evaluate the extent of sympathoexcitation and arrhythmogenicity during the left anterior descending coronary artery (LAD) ischemia. Extracellular in vivo and in situ spinal dorsal horn (DH) and intermediolateral column (IML) neural recordings were performed using a multichannel microelectrode array inserted at the T2-T3 segment of the spinal cord. SCS was performed for 30 min at 1 kHz, 0.03 ms, 90% motor threshold. LAD ischemia was induced pre- and 1 min post-SCS to investigate how SCS modulates spinal neural network processing of myocardial ischemia. DH and IML neural interactions, including neuronal synchrony as well as cardiac sympathoexcitation and arrhythmogenicity markers were evaluated during myocardial ischemia pre- vs. post-SCS. ARI shortening in the ischemic region and global DOR augmentation due to LAD ischemia was mitigated by SCS. Neural firing response of ischemia-sensitive neurons during LAD ischemia and reperfusion was blunted by SCS. Further, SCS showed a similar effect in suppressing the firing response of IML and DH neurons during LAD ischemia. SCS exhibited a similar suppressive impact on the mechanical, nociceptive and multimodal ischemia sensitive neurons. The LAD ischemia and reperfusion-induced augmentation in neuronal synchrony between DH-DH and DH-IML pairs of neurons were mitigated by the SCS. These results suggest that SCS is decreasing the sympathoexcitation and arrhythmogenicity by suppressing the interactions between the spinal DH and IML neurons and activity of IML preganglionic sympathetic neurons.

Rest and exercise early after sport-related concussion: a systematic review and meta-analysis

ObjectiveTo synthesise the evidence regarding the risks and benefits of physical activity (PA), prescribed aerobic exercise treatment, rest, cognitive activity and sleep during the first 14 days after sport-related concussion...

Investigation on the impact of B4C content in AA5052 based metal matrix composites on the mechanical properties of welded joints

In this research, the tungsten inert gas welding was used to join together metal matrix composites (MMCs) reinforced in different percentages with B4C. The welding settings were maintained at a constant value for all specimen situations. Thermal ageing was used to achieve maximum age-hardening in the welded composites. Misorientation and energy storage are the microscopic features of aged composites that distinguish them from composites that have not been aged. Tensile strength and hardness both increased with increasing B4C concentration, but at opposite rates, suggesting that hardness resulted from energy storage while tensile strength resulted from misorientation. Age hardening as measured by electron backscatter diffraction (EBSD) occurs due to a active recovery of the weld metal (WM) region following a reorganization in displacement structures caused by the precipitation of magnesium silicate or an increase in boron carbide content. The healing process is primarily driven by the action of precipitation strengthening, rather than the impact of obliteration of displacements, as evidenced by the correlation between tensile strength and reduction in misorientation. Adding B4C to aluminium metal matrix composites before welding causes the structural changes that need to be characterized. The welding process's structural changes are analysed, and connections are made to the welded junctions' mechanical behaviour. The study's findings suggest that the microstructure's misorientation distribution is as crucial as the average amount of misorientation in determining a material's strength.

IMPLEMENTATION OF ROBOTIC AND ASSISTIVE TECHNOLOGIES IN THE PATIENTCENTERED PHYSICAL REHABILITATION

There is a necessity for a consistent framework for the integration of the robotic and assistive technologies for the purposes of the rehabilitation which covers the entire spectrum (preventative, restorative, supportive, palliative rehabilitation) and explores all aspects of the of the recovery process – physical, emotional, and mental while allowing for real-time adjustments and flexibility based on the individual patients’ needs. In this paper we propose a set of tools for a rehabilitation solution that provides personalized care for the patients from the diagnose to the process of active recovery while measuring and evaluating the individual’s condition after surgery, injury or a trauma to restore and maximize the previous function. The main objective for implementing the assistive technologies into the physical therapy is to personalize the process of recovery based on the specific requirements of the patients. To achieve this, physical, emotional, and virtual devices are utilized mitigate and improve the physical and emotional challenges for the patients. In parallel with the implementation of the robotic technologies, custom-made 3D printed devices are also introduced and explored. To evaluate the effectiveness of the program, a 3-step methodology is applied – 1) diagnose of the patient, 2) implementation of the assistive technologies, 3) tracking the progress and making the necessary adjustments to the process and/or the devices.

Biosynthesis of diisooctyl 2,5-furandicarboxylate by Candida antarctica lipase B (CALB) immobilized on a macroporous epoxy resin.

Diisooctyl 2,5-furandicarboxylate (DEF), an ester derivative of 2,5-furandicarboxylic acid (FDCA, a bio-based platform chemical), resembles the physical and chemical properties of phthalates. Due to its excellent biodegradability, DEF is considered a safer alternative to the hazardous phthalate plasticizers. Although FDCA esters are currently mainly produced by chemical synthesis, the enzymatic synthesis of DEF is a green, promising alternative. The current study investigated the biosynthesis of DEF by Candida antarctica lipase B (CALB) immobilized on macroporous resins. Out of five macroporous resins (NKA-9, LX-1000EP, LX-1000HA, XAD-7HP, and XAD-8) evaluated, the LX-1000EP epoxy resin was identified as the best carrier for CALB, and the XAD-7HP weakly polar resin was identified as the second best. The optimal immobilization conditions were as follows: CALB (500μL) and LX-1000EP (0.1g) were incubated in phosphate butter (20mM, pH 6.0) for 10h at 35°C. The resulting immobilized CALB (EP-CALB) showed an activity of 639U/g in the hydrolysis of p-nitrophenyl acetate, with an immobilization efficiency of 87.8% and an activity recovery rate of 56.4%. Using 0.02g EP-CALB as the catalyst in 10mL toluene, and the molar ratio of 2,5-dimethyl furanediformate (1mmol/mL) and isooctyl alcohol (4mmol/mL) that was 1:4, a DEF conversion rate of 91.3% was achieved after a 24-h incubation at 50°C. EP-CALB had similar thermal stability and organic solvent tolerance compared to Novozym 435, and both were superior to CALB immobilized on the XAD-7HP resin. EP-CALB also exhibited excellent operational stability, with a conversion rate of 52.6% after 10 repeated uses. EP-CALB could be a promising alternative to Novozym 435 in the biomanufacturing of green and safe plasticizers such as DEF.

Therapeutic Strategies Targeting Respiratory Recovery after Spinal Cord Injury: From Preclinical Development to Clinical Translation.

High spinal cord injuries (SCIs) lead to permanent functional deficits, including respiratory dysfunction. Patients living with such conditions often rely on ventilatory assistance to survive, and even those that can be weaned continue to suffer life-threatening impairments. There is currently no treatment for SCI that is capable of providing complete recovery of diaphragm activity and respiratory function. The diaphragm is the main inspiratory muscle, and its activity is controlled by phrenic motoneurons (phMNs) located in the cervical (C3-C5) spinal cord. Preserving and/or restoring phMN activity following a high SCI is essential for achieving voluntary control of breathing. In this review, we will highlight (1) the current knowledge of inflammatory and spontaneous pro-regenerative processes occurring after SCI, (2) key therapeutics developed to date, and (3) how these can be harnessed to drive respiratory recovery following SCIs. These therapeutic approaches are typically first developed and tested in relevant preclinical models, with some of them having been translated into clinical studies. A better understanding of inflammatory and pro-regenerative processes, as well as how they can be therapeutically manipulated, will be the key to achieving optimal functional recovery following SCIs.

Investigating the effect of exercise on the expression of genes related to cardiac physiological hypertrophy.

Physiological hypertrophy of the heart is associated with an increase in the normal function of the heart, and it directly relates to regular exercise, especially among elite athletes. Researches about special signaling pathways that create physiological hypertrophy have recently received more attention. As a result, the present study was conducted to investigate the effect of aerobic exercise intensity on the expression of genes involved in heart physiological hypertrophy. For this purpose, 30 male Wistar rats were prepared and randomly divided into three groups: control, intense intermittent training, and submaximal continuous training. The intensive intermittent training protocol included 30 minutes of intermittent running, each interval including 4 minutes of running with an intensity of 85-90% VO2max and 2 minutes of active recovery with an intensity of 50-60% VO2max three days a week for 8 weeks. Also, the submaximal continuous exercise group had activity intensity equal to 50-55% of the maximum oxygen consumption. The expression of genes related to cardiac hypertrophy such as MMP-I, TGF-ß1, and TIMP was evaluated through real-time PCR technique. The results showed that the expression of studied genes in the three groups had significant differences (p<0.05). Both training methods led to a significant increase in TGF-ß1 and TIMP gene expression in the heart of rats. But the changes in MMP-I in the intermittent group were not significant compared to the control group. In general, it seems that exercise leads to the improvement of the factors involved in the physiological hypertrophy of the heart. Therefore, the findings of the current research are expressed with caution and more research is needed in the future.