Minimal Stress Research Articles

Stereotactic radiosurgery for pituitary and cavernous sinus metastases.

Metastases extending to the pituitary gland and cavernous sinus are extremely rare; however, advances in neuroimaging have increased the reported incidence. Stereotactic radiosurgery (SRS) affords the precise delivery of focused radiation to minimize adverse radiation effects. This study assessed the efficacy and safety of SRS in the treatment of pituitary and cavernous sinus metastases. Analysis was performed on 23 patients with pituitary and cavernous sinus metastases who underwent treatment using SRS between 1996 and 2021. The cohort was categorized into 2 groups in terms of metastasis location: pituitary involvement (Group 1, n = 11) and cavernous sinus involvement (Group 2, n = 12). Overall survival, local tumor control, and distal tumor control rates were compared between the two groups using Kaplan-Meier analysis. The median age of the cohort was 52.2years and the median tumor volume was 4.5mL. Overall survival rates were as follows: 1year (72.9%), 2years (51.8%), and 3years (45.3%). Local tumor control rates were as follows: 1year (82.3%), 2years (82.3%), and 3years (65.9%). Visual deficit and hypopituitarism were the most common presentations in Group 1, whereas cranial nerve deficit was the most common presentation in Group 2. SRS appears to be a safe and effective therapy for the treatment of pituitary and cavernous sinus metastases. GKRS is a relatively simple procedure, which places minimal stress on the patient, thereby facilitating further anti-cancer treatment. Considering the limited survival duration in cases of metastasis, it is very likely that post-GKRS complications (e.g., new onset cranial nerve deficit and hypopituitarism) would not become an issue before patient passes away.

Dose-dependent biological toxicity of green synthesized silver nanoparticles in rat’s brain

Metal nanoparticles, in general, and silver nanoparticles (AgNPs), in particular, have been the focus of numerous studies over the last two decades. Recently, the green synthesis of metal nanoparticles has been favored over chemical synthesis due to its low toxicity and easy preparation. The present study aims to investigate the dose-dependent toxicity of green synthesized AgNPs on rats’ brains. Thirty-four Wistar male rats were divided into four groups. The first, second, and third groups were administered for 14 days with three different doses (0.5, 5, and 10 mg/kg) of AgNPs, respectively. The fourth group, which served as a control group, was given normal saline for the same period. The toxicity of the green synthesized AgNPs on the cortical and hippocampal levels of the oxidative stress markers (MDA, NO, and GSH) as well as the activity of acetylcholinesterase (AchE) and the monoamine neurotransmitters (DA, NE, and 5H-T) were investigated. AgNPs showed minimal oxidative stress in the cortex and hippocampus for the administered doses. However, AgNPs showed an inhibitory effect on AchE activity in a dose-dependent manner and a decrease in the 5H-T and NE levels. The green synthesized AgNPs showed an ultrastructural change in the cellular membranes of the neurons. The green synthesis of AgNPs has reduced their cytotoxic oxidative effects due to their capping with biologically compatible and boosting molecules such as flavonoids. However, another neurotoxicity was observed in a dose-dependent manner.

Rumenotomy-induced Stress of Standing and Lateral Recumbency Restraints based on Physiologic Parameters and Interleukin-6 Expressions in Kano-Brown Goats

Ruminant welfare post-surgery could be improved by employing a procedural technique that causes minimal surgical stress. A total of twenty-four (n = 24) Kano Brown goats (KBGs) aged 1–2 years, weighing an average of 15.52 kg, were recruited for the study. Rumen skin clamp fixation (RSCF) and a stay suture rumenotomy (SSR) in lateral recumbency while standing restraint rumenotomy was aided by a locally fabricated mobile small ruminant surgical chute (MSRSC) were performed in groups A, B, and D, respectively, as control group C had no surgery. Six goats were allocated to each group such that each group had 3 males and females that were positive for rumen foreign body impaction (RFBI), except goats in group C that were free of RFBI. Pre- and post-rumenotomy values of vital parameters did not differ significantly (P > 0.05). The group A serum IL-6 concentrations at 72 hours post-rumenotomy (61.21 ± 44.52 ng/L) were significantly higher (P < 0.05) than those in group D (15.24 ± 3.09 ng/L) among the female KBGs. The concentrations of IL-6 at week 1 post-rumenotomy in group A were significantly higher (65.05 ± 31.11 ng/L) than in groups B (15.86 ± 0.29), D (18.75 ± 5.81) and C (14.86 ± 0.79 ng/L). The lack of significant changes in the mean values of rectal temperature, respiratory rate, and heart rate implies that the standing rumenotomy utilizing the MSRSC did not vary in surgical stress severity from the conventional approaches; RSCF and SSR, done in lateral recumbency. The IL-6 in group D was lower when compared to the values in group A females at 72 hours and at week 1 for the male KBGs, suggesting profound surgical stress among females and males in groups A and B over group D. Standing restraints cause less surgical stress than lateral recumbency restraints, making it a better procedural approach for rumenotomy in goats.

The ability of mouthguards to protect veneered teeth: A 3D finite element analysis.

Professional and amateur athletes might have veneer restorations. The aim of this study was to investigate the protective effect of mouthguards on veneered anterior restorations. A nonlinear dynamic analysis was performed to simulate conditions during an impact with or without a custom-made mouthguard. Using a computer-aided design (CAD) software, a slice of a human maxilla was designed containing an upper right central incisor. The model was composed of mucosa, cortical bone, trabecular bone, periodontal ligament, dentin, enamel, and pulp tissue. The enamel was prepared (feather design), restored with an indirect veneer (1.0 mm thickness), and duplicated to simulate both conditions with or without a mouthguard (4 mm thickness). Both models were subdivided into finite elements using the computer-aided engineering (CAE) software. Frictionless contacts were used, and an impact was simulated in which a rigid sphere hit the model at 1m s-1 . Fixation was defined at the base of the bone. The elastic modulus of the veneer was assessed by using five different restorative materials (resin composite, hybrid ceramic, zirconia-reinforced lithium silicate, lithium disilicate, and zirconia). Von Mises stress, minimal principal stress, and maximum principal stress (in MPa) were obtained and plotted for visual comparison. Von-Mises results showed higher stress concentrations in the veneer's cervical labial region for models without a mouthguard. Observing the quantitative results for each model, the highest compressive (709 MPa) and tensile (58 MPa) stresses occurred in the situation without a mouthguard with a zirconia veneer, while the lowest occurred in resin composite veneer with a mouthguard (8 and 5MPa). The mouthguard was able to reduce the stresses in the tooth structure and it also reduced the risk of fracture in all conditions. Mouthguards were beneficial in reducing the effects of dental trauma regardless of the restorative material used to manufacture the indirect veneer, since they act by dampening the generated stresses during the trauma event. Equal impact stresses on a mouthguard will lead to higher stresses in veneered teeth with more rigid restorative materials leading to a less protective effect.

Study on H-shaped fracture propagation and optimization in shallow dull-type coal seams in the Hancheng block, China

The initiation and propagation of hydraulic fractures dominate the fracture morphology and conductivity, thereby determining the fracturing stimulation effect. This work took the shallow dull-type coal seam in the Hancheng block as the research object, and focused on the propagation and optimization of the H-shaped fracture. By using a combination of mechanical theoretical analysis, laboratory experiment, numerical simulation, field test, and optimization evaluation, an integrated study on the formation conditions, morphology evolution, propagation laws, main controlling factors, and optimal design of H-shaped fractures was conducted. The mechanical criterion for identifying H-shaped fracture propagation was derived through the analysis of the stress fields on the fracture surface. A 3D numerical model of H-shaped fractures was established with cohesive element method, and the propagation law and influencing factors of H-shaped fractures were investigated. Sensitivity analysis of the influencing factors on the H-shaped fractures was performed with grey incidence analysis method. The optimization of the H-shaped fracture parameters was performed by fracture propagation numerical simulation. The results show that H-shaped fractures dominated by horizontal fractures are generally formed in shallow dull-type coal seams. H-shaped fractures can improve the CBM development effect by parameter optimization of indirect fracturing technology. The judging criterion for H-shaped fracture formation is that the tensile strength of the upper and lower weakly cemented horizontal interfaces is less than that of the coal seam and the vertical principal stress is lower than the minimal horizontal principal stress. The incidence degree of fracturing fluid injection rate, viscosity, perforation location, minimum horizontal stress difference, and coal seam permeability on the H-shaped fracture propagation decreases in turn. The engineering factors (fracturing fluid injection rate and viscosity and perforation location) are the major impact factors. With the increase in coal seam permeability, the horizontal fracture develops from stubby-type to slender-type. The minimum horizontal principal stress difference mainly affects the horizontal fracture. As the fracturing fluid viscosity increases, the horizontal fracture length increases first and then decreases. The fracturing fluid injection rate has a great impact on the height-length profile of horizontal fractures. The optimal injection rate seems to be 6.5–7 m3/min, the optimal fracturing fluid viscosity is between 10 mPa·s and 15 mPa·s, and the optimal perforation location is selected near the formation interface. These research results could provide a reference for the design and optimization of efficient fracturing of coalbed methane reservoirs.

Finite element and multivariate random forests modelling for stress shield attenuation in customized hip implants

Primary total hip replacement surgery has an undisputable reputation as a widely successful orthopaedic operation, but it is beset by a phenomenon known as stress shielding. The cause of stress shielding is multifaceted. However, its reduction is reported to be hinged on the optimal design of prosthetic implants. Yet, to date, the design of a hip implant profile that behaves biomechanically similar to the natural physiological load-bearing zones of the femur remains an open problem. Along this vein, this paper instantiates an inquiry into the development of a framework that couples the capability of the finite element analysis (FEA) with that of machine learning methods toward the discovery of optimal design parameters for a customized hip implant. First, premised on the properties of a commercial normal-stem hip implant, a baseline computer-aided design (CAD) parametric model was created. From the baseline CAD model, a database of 120 hip implant profiles is established from the perturbation of the lateral edge, lateral angle, and the ratio of the radial cross-sectional areas of the implant. Next, the validation of the developed finite element procedure was conducted on a healthy intact femur and detailed numerical simulations were undertaken to assess the stress shielding (SS) attributes of all hip implants in the established database. The ensuing stress and strain data from the FEA is then deployed to ward a data-driven inverse model based on the random forests machine learning algorithm. Results-wise, the validation of the static analysis on the intact femur yielded von Mises stresses that matched those reported in published studies. Moreover, other results from the FEA revealed that a rectangular cross-sectioned hip implant resulted in the highest SS in the four zones of the proximal femoral compared to the trapezoidal cross-sectioned implant. Further, the inverse RF model exhibited excellent predictive capability and was subsequently employed towards the retrieval of the optimal geometric parameters that will manifest minimal stress shielding effect.

Investigation of the Effect of Copper Addition on Physical and Mechanical Properties of TiNi-Cu Porous Alloy

This work is devoted to the physical and mechanical properties of porous alloys based on TiNi alloyed with different amounts of Cu additive. We show that by doping a porous TiNi alloy with copper instead of nickel, it is possible to obtain characteristics acceptable for use in implantology and superior to those of known porous TiNi alloys. Cu addition in the range from 1 to 10 at.% is shown to optimize the properties of tested alloys. There is a decrease in the minimal martensitic transformation stress τMsmin from 37 to 17 MPa when compared to initial unalloyed TiNi. Alloys with 3 and 6 at.% of Cu are found to be optimal for use in medical practice. Along with a wide temperature range of reversible deformations that cover the range of operating temperatures (273–313 K), such alloys demonstrate their martensitic transformation stress values below 28 MPs. This permits to model implantable structures of complex configuration from such materials under a certain temperature regime.

The Hollow Porous Sphere Cell Carrier for the Dynamic Three-Dimensional Cell Culture.

Large-scale mammalian cell culture is essential in cell therapy, vaccine production, and the manufacturing of therapeutic protein drugs. Due to the adherent growth characteristic of most mammalian cell types, the combination of cell carrier and bioreactor is a common choice in large-scale mammalian cell culture. Current cell carriers developed by polymer crosslinking, lithography, or emulsion drops are unable to obtain a structure with uniformed porous structure and porous interior design, which results in an inhomogeneous culture condition for cells and therefore cannot ensure an optimal dynamic culture condition for cell proliferation, matrix production, and cell differentiation. In addition, the fluidic shear stress (a standard mechanical stimulation in bioreactor culture) and inner-carrier velocity (to ensure nutrient transport and waste exchange), which influence cell viability and growth, are not well-controlled/analyzed due to an irregular porous structure with these traditionally synthesized cell carriers. To solve these problems, we designed four types of hollow porous spheres (HPS, 1.0 cm diameter) with different porous structures. To investigate the impacts of porous structure on surface shear stress and inner velocity, computational fluid dynamics (CFD) simulations were conducted to analyze the liquid flow behavior in HPSs, based on which an optimal structure with minimal surface shear stress and best inner velocity was obtained and fabricated using fused deposition modeling three-dimensional (3D) printing technology. Inspired by the industrial large-scale culture system, a novel 3D dynamic culture system was then established using HPSs to seed the cells, which were then placed in a mini bioreactor on a tube roller. CFD analysis showed that under 0.1 m/s water flow, the shear stress at most surface areas from four HPSs was lower than 20 dynes/cm2, which suggests that the HPSs should provide protection against physical stress to the cells living on the scaffold surface. A dynamic cell seeding was developed and refined using the 3D culture system, which increased the 32% seeding efficiency of MC3T3 cells compared to the traditional static cell seeding method. The cell proliferation analysis demonstrated that HPSs could speed up cell growth in dynamic cell culture. The HPS with a honeycomb-like structure showed the highest inner pore velocity (CFD analysis) and achieved the fastest cell proliferation and the highest cell viability. Overall, our study, for the first time, developed a 3D printed HPS cell culture device with a uniformed porous structure, which can effectively facilitate cell adhesion and proliferation in the dynamic cultural environment, thereby could be considered an ideal carrier candidate.

Unjamming strongly compressed rafts: Effects of the compression direction.

We experimentally study the unjamming dynamics of strongly compressed particle rafts confined between two fixed walls and two movable barriers. The back barrier is made of an elastic band, whose deflection indicates the local stress. The front barrier is pierced by a gate, whose opening triggers local unjamming. Prior to gate opening, the rafts are quasistatically compressed by moving only one of the two barriers, in the vicinity of which folds form. Using high-speed imaging, we follow the raft relaxation with folded, jammed, and unjammed areas and measure the velocity fields inside and outside the confined domain. Two very different behaviors develop. For rafts compressed by the back barrier, only partial unjamming occurs. At the end of the process, many folds remain and the back stress does not relax. The flow develops mostly along the compression axis and the particles passing the gate form a dense raft whose width is the gate width. For rafts compressed at the front, quasitotal unjamming is observed. Almost no folds persist and only minimal stress remains, if any. The particles flow along the compression axis but also normally to it and form a rather circular and not dense assembly. Both the force chain network orientation and the initial fold location could cause the unjamming difference. Other effects, such as a different pressure field or simple steric hindrance, cannot be excluded.

Investigation of oxidative damage, antioxidant balance, DNA repair genes, and apoptosis due to radiofrequency-induced adaptive response in mice

ABSTRACT This study aims to determine whether exposure to non-ionizing radiofrequency fields could induce an adaptive response (AR) in adult mice and to reveal potential molecular mechanisms triggered by RF-induced AR. The study was performed on 24 adult male Swiss-Albino mice. The average mass of the mice was 37 g. Four groups of adult mice, each consisting of 6, were formed. The radiofrequency group (R) and the adaptive response group (RB) were exposed to 900 MHz of global system for mobile communications (GSM) signal at 0.339 W/kg (1 g average specific absorption rate) 4 h/day for 7 days, while the control group (C) and the bleomycin group (B) were not exposed. 20 minutes after the last radiofrequency field (RF) exposure, the mice in the B and RB groups were injected intraperitoneal (ip) bleomycin (BLM), 37.5 mg/kg. All the animals were sacrificed 30 minutes after the BLM injection. Oxidative damage and antioxidant mechanism were subsequently investigated in the blood samples. Changes in the expression of the genes involved in DNA repair were detected in the liver tissue. TUNEL method was used to determine the apoptosis developed by DNA fragmentation in the liver tissue. The RB group, which produced an adaptive response, was compared with the control group. According to the results, the increase of reactive oxygen species (ROS) in the RB group may have played an important role in triggering the adaptive response and producing the required minimum stress level. Furthermore, tumor suppressor 53(p53), oxo guanine DNA glycosylase (OGG-1) levels responsible for DNA repair mechanism genes expression were increased in conjunction with the increase in ROS. The change in the poly (ADP-ribose) polymerase 1 (PARP-1) and glutathione peroxidase 1 (GPx-1) gene expression were not statistically significant. The antioxidant enzyme levels of superoxide dismutase (SOD), catalase (CAT), and total antioxidant capacity (TAC) were decreased in the group with adaptive response. According to the data obtained from terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) analysis, apoptosis was decreased in the RB group due to the decrease in cell death, which might have resulted from an increase in gene expression responsible for DNA repair mechanisms. The results of our study show that exposure to RF radiation may create a protective reaction against the bleomycin. The minimal oxidative stress due to the RF exposure leads to an adaptive response in the genes that play a role in the DNA repair mechanism and enzymes, enabling the survival of the cell.

The psychosocial health, experiences and needs of older adults and care partners during the first surge of the COVID-19 pandemic: a mixed-methods study

BackgroundMinimal research has leveraged qualitative data methods to gain a better understanding of the experiences and needs of older adults (OAs) and care partners of OAs with and without Alzheimer’s Disease (AD) and AD-related dementias (AD/ADRD) during the first surge of the COVID-19 pandemic. In this study, we: 1) quantitatively evaluated the psychosocial health of community-dwelling OAs; 2) quantitatively evaluated the perceived stress of care partners for OAs; 3) qualitatively characterized the experiences and needs of community-dwelling OAs and their care partners; and 4) explored differences in the experiences of care partners of OAs with and without AD/ADRD during the first surge of the COVID-19 pandemic in the New York metropolitan area.MethodsIn this mixed-methods study, telephone interviews were conducted with 26 OAs and 29 care partners (16 of whom cared for OAs with AD/ADRD) from April to July 2020. Quantitative data included: demographics; clinical characteristics (Katz Index of independence in activities of daily living (Katz ADL) and the Lawton-Brody instrumental activities of daily living scale (Lawton-Brody)); and psychosocial health: stress was assessed via the Perceived Stress Scale (PSS), social isolation via the Lubben Social Network Scale (LSNS), loneliness via the DeJong Loneliness Scale (DeJong), and depression and anxiety via the Patient Health Questionnaire-Anxiety and Depression (PHQ). Qualitative questions focused on uncovering the experiences and needs of OAs and their care partners.ResultsOAs (N = 26) were mostly female (57.7%), and White (76.9%), average age of 81.42 years. While OAs were independent (M = 5.60, Katz ADL) and highly functional (M = 6.92, Lawton-Brody), and expressed low levels of loneliness, stress, depression and anxiety (M = 1.95 on DeJong; M = 12.67 on PSS; M = 1.05 on PHQ depression; and M = 1.09 on PHQ anxiety), open-ended questions elicited themes of fear and worry. Care partners (N = 29) were mostly female (75.9%), White (72.4%), and married (72.4%), and reported moderate stress (M = 16.52 on the PSS), as well as a psychological impact of the pandemic.ConclusionsEarly in the pandemic, OAs reported minimal stress and loneliness; this may have been related to their reports of frequent interaction with family, even if only virtually. By contrast, care partners were moderately stressed and worried, potentially more than usual due to the additional challenges they face when trying to meet their loved ones’ needs during a pandemic.

Research on the effect of thermal fracture failure behavior on thermal friction of flexible cable

Flexible cables play significant role in the field of intelligent production and manufacturing. However, with prolonged use, wear will inevitably occur, threatening the safety of operators. And the high temperature of the working will accelerate wear. Hence, the effect of the high temperature was investigated in wear performance of flexible cable. The friction and wear evolution at high temperatures were studied combining the tension stress and elongation. The results show the interaction of heat and wear affects cable friction. At high temperature maximum frictional force increases by 68.93 % compare to the lowest friction at low temperature; the wear is accelerated maximum 90 %. The minimal tensile stress and the elongation at break of cable appear at 1.5 h, which is consistent with the friction force and wear results.

A Minimally Invasive, Accurate, and Efficient Technique for Intrathymic Injection in Mice.

Intrathymic injection in mouse models is an important technique for studying thymic and immune function, including genetic and acquired T cell disorders. This requires methods for the direct deposition of reagents and/or cells into the thymus of living mice. Traditional methods of intrathymic injection include thoracic surgery or minimally invasive percutaneous blind injections, both of which have significant limitations. Ultra-high frequency ultrasound imaging devices have made image-guided percutaneous injections possible in mice, greatly improving the injection accuracy of the percutaneous injection approach and enabling the injection of smaller targets. However, image-guided injections rely on the utilization of an integrated rail system, making this a rigid and time-consuming procedure. A unique, safe, and efficient method for percutaneous intrathymic injections in mice is presented here, eliminating reliance on the rail system for injections. The technique relies on using a high-resolution micro-ultrasound unit to image the mouse thymus noninvasively. Using a free-hand technique, a radiologist can place a needle tip directly into the mouse thymus under sonographic guidance. Mice are cleaned and anesthetized before imaging. For an experienced radiologist adept at ultrasound-guided procedures, the learning period for the stated technique is quite short, typically within one session. The method has a low morbidity and mortality rate for the mice and is much faster than current mechanically assisted techniques for percutaneous injection. It allows the investigator to efficiently perform precise and reliable percutaneous injections of thymuses of any size (including very small organs such as the thymus of aged or immunodeficient mice) with minimal stress on the animal. This method enables the injection of individual lobes if desired and facilities large-scale experiments due to the time-saving nature of the procedure.

Size effects in stress propagation and dynamics of dislocations: Fe–Ni–Cr steel

Movement of line dislocations in fcc steel 310S is found to depend on the size of nanometer sized structures, based on modeling within molecular dynamics (MD). The effect is attributed to time (and size) dependencies of pressure propagation into the medium interior. The observation is crucial in interpreting any MD studies of pressure effects since these are governed by time-dependent internal virial stresses. In particular, velocity of dislocations scales better with value of local internal shear component of virial stress S xy than with external shear pressure applied. Dynamics of stress penetration is described well within the model of damped harmonic oscillator, where characteristic oscillation frequency depends on number of crystallographic layers in direction along the wave propagation while the speed of stress propagation is the speed of sound. The minimal stress required for dislocation movement (Peierls stress) is determined to be 0.75 GPa. Pressure and temperature effects on dislocation movement are systematically investigated.

Impact of Emergency Remote Teaching on University Students at a Public Institution in the United States

The educational experiences of university students participating in Emergency Remote Teaching (ERT) during the COVID-19 pandemic were evaluated using a survey instrument. Students found ERT stressful (89%) and indicated challenges from inadequate internet (91%), lack of privacy (45%), and increased amount of studying (3 hours more per week). Academic rank correlated with stress level during ERT, with freshmen (42%) reporting the highest stress level and seniors (48%) reporting minimal stress. Lack of face￾to-face instruction, missing peer interaction and having to teach the course material to themselves were the top issues that students disliked with ERT. Respondents recognized the need for organization, self￾motivation, and increased interaction with other students and instructors as key factors for effectiveness and satisfaction of ERT instruction.

Enhancing mechanical properties of 3D printed thermoplastic polymers by annealing in moulds

Five series of specimens with two different print orientations (−45/45 and 0/90) and two print layer thicknesses (0.1 and 0.2 mm) were made. In total 60 specimens with 100% filament infill were made. One specimen series (20 pieces) was isolated as a reference or thermally untreated. Before the thermal treatment (annealing), two specimen moulding methods were used: NaCl powder (granulation 63 mm: 20 pieces) and Calcium Sulphate (Gypsum: 20 pieces). During the annealing, specimens immersed in NaCl powder were heated in a drying oven to the filament melting point (for PLA: 200°C, with a duration interval of 30 min), while the treatment of the heated specimens in gypsum was performed at a temperature of around 190°C, with duration interval of 3 h with the observed temperature inside the mould of about 100°C. An ultrasonic bath and a drying oven were used in the gypsum treatment. Temperature measurement and control during both annealing treatments were performed using a thermal imaging camera, while the temperature control inside the drying oven was performed using a digital thermometer. After treatment, the specimens in the moulds were cooled at room temperature, and the dimensions of annealing and untreated specimens were controlled. Surface morphology was characterised using scanning electron microscopy (SEM). The SEM analysis reveals improved internal structure after heat treatment of the PLA specimens. These results show that the investigated specimens after heat treatments had better structural properties than the referent specimens. Tensile testing on a universal testing machine in compliance with the ASTM D638 standard was also performed. The referent PLA specimen with −45/45 and layer thickness of 0.1 mm had the highest tensile stress value (64.08 MPa) while the specimen with minimal tensile stress value before fracture was 0/90, 0.2 mm (54.81 MPa). Heat treatment in gypsum showed the most significant increase in strength with −45/45 (0.1 mm) being the strongest (71.66 MPa) while the strongest specimen treated in sodium chloride was −45/45 (0.1 mm) with maximum tensile stress of 70.08 MPa. The mechanical characteristics of the PLA were characterised using the Vickers microhardness tester. The PLA microhardness value was calculated according to standards ASTM E384 and ISO 6507. The referent PLA specimen with −45/45 (0.2 mm) orientation shows the maximal microhardness value (125 MPa), and the minimal microhardness value was observed for the 0/90 (0.1 mm) orientation specimens (108 MPa). The heat treatment specimens in gypsum have a better hardness (185 MPa) than those treated in gypsum (165 MPa), with microhardness increasing by about 12%. The essence of the work is reflected in the additional filament processing to achieve a better structural and mechanical performance of the materials and reduce the anisotropy that is characteristic of 3D printing.

In Vivo Evaluation of an Antibody-Functionalized Lipoidal Nanosystem for Schistosomiasis Intervention.

This study employed nanotechnological techniques to design and develop a praziquantel nanoliposomal (NLP) system and surface-functionalized the NLP with anti-calpain antibody (anti-calpain-NLP) for targeted praziquantel (PZQ) delivery in the treatment of schistosomiasis. Anti-calpain-NLPs were prepared and validated for their physicochemical parameters, in vitro and in vivo toxicity, drug entrapment efficiency (DEE), drug loading capacity (DLC), drug release, and parasitological cure rate. The particle sizes for the formulated nanoliposomes ranged from 88.3 to 92.7 nm (PDI = 0.17–0.35), and zeta potential ranged from −20.2 to −31.9 mV. The DLC and DEE ranged from 9.03 to 14.16 and 92.07 to 94.63, respectively. The functionalization of the nanoliposome surface was stable, uniform, and spherical. Fourier-transform infrared (FTIR), thermal behavior and X-ray powder diffraction (XRPD) analysis confirmed that the anti-calpain antibody and PZQ were attached to the surface and the nanoliposomes inner core, respectively. The drug sustained release was shown to be 93.2 and 91.1% within 24 h for NLP and anti-calpain-NLP, respectively. In the in vitro analysis study, the nanoliposome concentrations range of 30 to 120 μg/mL employed revealed acceptable levels of cell viability, with no significant cytotoxic effects on RAW 264.7 murine macrophage as well as 3T3 human fibroblast cells. Biochemical markers and histopathological analysis showed that the formulated nanoliposomes present no or minimal oxidative stress and confer hepatoprotective effects on the animals. The cure rate of the anti-calpain-NLP and PZQ was assessed by parasitological analysis, and it was discovered that treatment with 250 mg/kg anti-calpain-NLP demonstrated greater activity on the total worm burden, and ova count for both the juvenile and adult schistosomes in the intestine and liver of infected mice. The findings so obtained supported the ability of oral anti-calpain-NLP to target young and adult schistosomes in the liver and porto-mesenteric locations, resulting in improved effectiveness of PZQ.

Closed Suction Drain Placement Using a Carroll Tendon Retriever.

The technique used for closed suction drain placement in plastic surgery is dependent on surgeon preference and experience. Drains assist in preventing accumulation of inflammatory seroma fluid, but they also present a possible nidus for infection, which is particularly concerning in implant-based breast reconstruction. Murray et al.1 retrospectively reviewed 200 cases of breast reconstruction with tissue expander placement and found that subcutaneous tunneling is one factor that may defend against infection by means of in vivo protection of the prosthesis from the drain. This clinical practice is echoed in the neurosurgery literature, where several studies have shown that long subcutaneous tunneling decreases the incidence of surgical site infection in neurosurgical procedures.2,3 Yoshida et al.4 recently described a method of drain placement into the breast pocket utilizing a liposuction cannula. While their method is innovative and effective, we would like to propose another technique with the similar advantage of using readily available operating room instruments but that is simpler and more ergonomic. The method utilizes a Carroll tendon retriever, commonly referred to as a tendon passer by plastic and hand surgeons, to place a tunneled closed-suction drain for implant-based breast reconstruction through a long subcutaneous plane with minimal disruption and stress to surrounding tissues. We begin by selecting a drain insertion site lateral to the breast pocket at the level of the inframammary fold to allow for at least 5 cm of subcutaneous tunneling. This location permits the scar to be hidden by a bra. After creating a stab incision, the surgeon inserts a Carroll tendon retriever with jaws closed and advances it manually with gentle, constant pressure through the subcutaneous plane into the breast pocket. The jaws are then opened to grasp the external end of the drain and draw it out from the upper outer breast pocket through the tunnel. The drain is secured with nonabsorbable suture and dressed with a sterile adhesive dressing. [See Video (online), which demonstrates the use of a Carroll tendon retriever to facilitate drain placement into a breast pocket.] {"href":"Single Video Player","role":"media-player-id","content-type":"play-in-place","position":"float","orientation":"portrait","label":"Video.","caption":"This video demonstrates the use of a Carroll tendon retriever to place a drain tube into a breast pocket.","object-id":[{"pub-id-type":"doi","id":""},{"pub-id-type":"other","content-type":"media-stream-id","id":"1_acjzm5ek"},{"pub-id-type":"other","content-type":"media-source","id":"Kaltura"}]} The Carroll tendon retriever has several advantages over other common methods of placing tunneled drains. This technique facilitates atraumatic creation of a long subcutaneous tunnel. In contrast to either a tonsil or a hemostat, both of which have a shank that splays widely toward the handle in the tissue, the Carroll tendon retriever has a static, narrow body that forms a uniform-sized tunnel. Its blunt tip makes it a safer alternative to using a trocar for drain placement. Lastly, the Carroll tendon retriever is well known to plastic and hand surgeons and is reusable and reasonably inexpensive. DISCLOSURE The authors have no financial interest to declare in relation to the content of this article. No direct funding was provided for this study.

Shape memory effect in TiNi single crystals with thermal-induced martensite transformation or strain glass transition

In present work, we investigated the thermoelastic B2-B19' martensitic transformations in thermocycles under constant stress, σapp, (ε(Т) curves) and in loading/unloading cycles (σ(ε) curves) in quenched [001]-oriented single crystals of Ti-50.7 at%Ni and Ti-51.7 at%Ni alloys. Single crystals undergo either thermal-induced В2-В19' martensitic transformation (Ti-50.7 at%Ni) or strain glass transition (Ti-51.7 at%Ni), depending on their chemical composition. The transformation type defines the morphology of a martensite during cooling under stress. In Ti-50.7 at%Ni alloys during stress-assisted cooling the morphology is the mix of self-accommodation martensite and oriented martensite. In opposite, in Ti-51.7 at%Ni alloys the morphology consists of oriented martensite only. The following parameters in stress-assisted cooling/heating cycles are determined by transformation type and morphology of a martensite: the minimal stress, σmin, for oriented martensite formation; the coefficient dεfor/dσ that defines the strain dependence on stress, εfor(σapp), and the presence of additional stage in the dependence Msσ(σapp). Similar in loading/unloading cycles the transformation type defines the energy barrier that should be overcome in order to start the stress-induced martensitic transformation, and, so, the stress level, σcr(Ms0).

2022 ISFM Consensus Guidelines on Management of the Inappetent Hospitalised Cat.

Inappetence may have many origins and, as a presenting sign or observation in the hospitalised patient, is common in feline practice. Nutritional assessment of every patient is encouraged, to identify the need for, and appropriate type of, intervention indicated. The impact of malnutrition may be significant on the feline patient, perpetuating illness, delaying recovery, slowing wound healing and negatively impacting gut health and immunity. Delayed intervention may result in the cat's deterioration; hence prompt control of contributing factors such as the underlying illness, pain, nausea, ileus and stress is vital to optimise voluntary food intake. Management is multimodal, comprising reduction of stress, medications and assisted nutrition in the form of tube feeding or parenteral nutrition. Use of antiemetic, analgesic, prokinetic and appetite stimulant medications may restore appetite, but placement of feeding tubes should not be delayed. Feeding tubes are generally well tolerated and allow provision of food, water and medication with minimal stress, although clinicians must be aware of complications such as stoma site infections and refeeding syndrome. Cats are vulnerable to malnutrition owing to their unique metabolism and specific nutritional requirements. Moreover, their nature as a species means they are susceptible to stress in the hospital environment, which may result in reduced food intake; previous negative experiences may compound the problem. In particular, an inappropriate clinic environment and/or handling may cause or exacerbate inappetence in hospitalised patients, with negative impacts on recovery. Postponing interventions such as feeding tube placement to await improvement, owing to clinician or caregiver apprehension, may hinder recovery and worsen nutritional deficits. The 2022 ISFM Consensus Guidelines on Management of the Inappetent Hospitalised Cat have been created by a panel of experts brought together by the International Society of Feline Medicine (ISFM). Information is based on the available literature, expert opinion and the panel members' experience.