Application Of Pressure Research Articles

Effect of high-pressure homogenization pretreatment on gelation behavior and physicochemical, rheological and structural properties of sesame protein isolate with glucono-δ-lactone

This study investigated the gelation of sesame protein isolate induced by high-pressure homogenization (HPH) with glucono-δ-lactone (GDL) acidification, focusing on the effect of pressures on gelation behavior and physicochemical, rheological and microstructural properties of the resulting gels. The HPH significantly affected the acidification kinetic parameters such as Vmax, Tmax, T5, and T4.5. The maximum Vmax (0.062 pH units/min) value was determined in the sample treated with 100 MPa, and T4.5 was decreased by 30 min with HPH at 50 and 100 MPa pressures. The particle size of sesame protein decreased with the homogenization pressure increased, and this played a role in the formation of lower particle size aggregates after gelation. The highest water holding capacity (69.02%) and gel strength (7.9 g) were reached with a pressure at 100 and 150 MPa, respectively. While a significant increase in the whiteness index of gels was observed by increasing pressure up to 100 MPa, the highest total color difference (ΔE) was detected at 50 MPa. The G′ value of the samples tended to increase with gelation time and with the high pressure applied, indicating a significant improvement in the elasticity of the gels. All gel samples exhibit shear-thinning behavior. Hydrophobic interactions were dominant in the gel samples, and the highest value (8.28 mg/g) was determined in the sample prehomogenized at 100 MPa. This study revealed that the gelation properties of sesame protein induced by GDL can be improved with HPH and that 100 MPa pressure application is ideal.

#132 Electrocauterization versus ligation of lymphatic vessels to prevent lymphocele development after kidney transplantation—a meta-analysis

Abstract Background and Aims Lymphoceles are amongst the most common complications following kidney transplantation. They can cause pain, discomfort, and even transplant malfunction or graft loss through the application of pressure on the graft as well as its surrounding structures. Therefore, effective strategies to prevent their development are needed. The ligation of lymphatic vessels has proven to be a successful concept for that purpose. However, whether electrocauterization or suture ligation is more effective is unclear. Method We conducted a meta-analysis using a random effects model with the log risk ratio as primary outcome measure. Additionally, an analysis using a random effects model with the raw mean difference in lymphatic sealing time between suture ligation and electrocauterization was performed. Adequate studies were found in a literature research conducted on PubMed and Web of Science as well as from independent sources. Results A total of 7 studies including 511 patients were included in the analysis. 16/244 (6.5%) lymphoceles were observed in the electrocauterization group and 28/267 (10.5%) in the suture ligation group, resulting in an overall incidence of 44 (8.6%) in the total population. The estimated average log risk ratio based on the random-effects model was µ=−0.349 (95% CI: −0.934 to 0.235), not significantly different from zero (z=−1,17, p=0.241). Lymphatic sealing time was 7.28 (95% CI: 1.25-13.3, p=0.018) minutes shorter in the electrocauterization group. Conclusion We conclude that neither technique is superior for the purpose of lymphocele prevention post kidney transplantation and secondary criteria like time saving, cost and surgeons’ preference should be considered in the decision for optimal outcome. However, it is unclear whether these results can be generalized for all patients.

Pressure effects on the structural, electronic, elastic, optical, and vibrational properties of YMg intermetallic compounds: a first-principles study

The properties of YMg in B2 structure have been comprehensively analysed using the first-principles plane-wave pseudopotential method. Specifically, the structural, electronic, elastic, vibrational, and optical properties were investigated using the generalized gradient approximation (GGA) method in the context of density functional theory. The Vienna ab initio simulation package (VASP) was utilized for these calculations. The computed lattice parameter (3.803 Å) and bulk modulus (41.33 GPa) are consistent with the earlier data on ambient pressure. The electronic band structure and energy-dependent density of states reveal the metallic nature of the titled compounds. The Born stability requirements confirmed the mechanical stability. The analysis of Pugh’s and Poisson’s ratios and Cauchy’s pressure reveals that YMg is ductile under the pressures in consideration. According to several anisotropy indices, the compound is noticeably anisotropic both in ambient and under pressure. Our investigation includes an analysis of several fundamental mechanical parameters of the material, including the bulk modulus, the pressure derivative of the Zener anisotropy factor, Poisson’s ratio, isotropic shear modulus and Young’s modulus with a particular focus on their dependence on pressure. We have determined that the elastic constants obtained remain mechanically stable, satisfying the Born Stability conditions even at high pressures of up to 60 GPa. To explore the dynamic stability of YMg, we analysed the material’s phonon dispersion curves. The examined compound displays stability under dynamic conditions from 0 GPa to 30 GPa, as evidenced by its positive vibration frequencies. However, this stability is not sustained under higher pressure, as the compound becomes unstable after 30 GPa to 70 GPa. The electronic band structure and density of states diagrams demonstrate YMg’s metallic properties. At atmospheric pressure (0 GPa), the total density of states (TDOS) near the Fermi level is approximately 1.63 states/eV, with pressure application reducing DOS. The dielectric function, refractive index, and energy loss spectra are examined within the 0–20 eV energy range. YMg exhibits its highest absorption between 4 and 11 eV. The peak optical conductivity is observed around 0.78 eV (equivalent to 1589.5409 nm), while the most significant energy loss occurs at 11.90 eV, roughly corresponding to 2.8 Hz in the ultraviolet spectrum. Moreover, we extensively analyzed the material’s phonon thermodynamic and optical properties, providing insights into its behavior under various conditions. The outcomes acquired at zero pressure are generally coherent with the current theoretical values.

Enhanced self-polarization effect by tuning interfacial binding energy for self-powered flexible piezoelectric pressure sensors

Flexible pressure sensors based on PVDF and its copolymers have been extensively investigated due to their unique self-powered characteristics and high sensitivity. Herein, a new strategy of manipulation the interfacial binding energy between the organic and inorganic groups has been utilized to enhance the performance of the flexible piezoelectric pressure sensors. Four types of interfacial interactions of different binding energy have been designed in the polydopamine (PDA) decorated lead zirconate titanate (PZT) and P(VDF-TrFE) composites. The results based on first-principles calculations reveal that PDA acts as a binder between PZT and P(VDF-TrFE) due to the strong interaction between -NH2 and -CF2- dipoles. The strong interaction results in enhanced self-polarization effect and enhanced piezoelectric effect, and the improved sensitivity of the pressure sensors. The β-phase content of P(VDF-TrFE) increases from 17% to 87% when the content of PZT@PDA nanoparticles reaches 15 wt%. PZT@PDA/P(VDF-TrFE) self-powered pressure sensor (SPPS) exhibits an output voltage of 44 V and a high sensitivity of 1.38 V/kPa with no significant performance degradation during 10,000 cycles of pressure application. Moreover, the SPPS shows an excellent self-powered ability with the highest short-circuit current of 8.6 μA and the peak power density of 15 μW/cm2. The SPPS demonstrates the extraordinary sensing performance in body motion sensing and hand gesture recognition.

Feasibility Study of Using the Integrated Telemedicine Platform “IS-cardio” for Outpatient Cardiological Rehabilitation: Single-Centered Cohort Study

INTRODUCTION. The implementation of remote cardiac rehabilitation (RCR) technology based on telemedicine platforms (TMP) requires a preliminary assessment of the feasibility of use. AIM. A preliminary study of the feasibility of using the integrated TMP “IS-cardio” to perform RCR in patients with cardiovascular diseases (CVD) in the context of need, feasibility and acceptability. MATERIALS AND METHODS. Single-center cohort study of patients (n = 33; 75 % men; mean age 56 ± 8 years) with CVD. Testing of the TMP «IS-cardio» was carried out during 12-week physical training (PT) programs with an intensity of 55 %. Feasibility was assessed according to the following criteria: need, feasibility, acceptability. Data on need and acceptability were obtained from a patient survey. Feasibility was assessed as the proportion of patients completing RCR. Remote monitoring was performed using heart rate, blood pressure, electrocardiogram and mobile application recorders. Feedback was provided in the form of electronic reports and delayed consultation. Patient satisfaction was assessed in points. RESULTS. 79.2 % of respondents were interested in telemedicine monitoring. 100 % of patients completed RCR; 12 patients (39.6 %) fully completed the PT program. The patients’ activity amounted to 2.4 ± 0.7 PT sessions per week; the average duration of PT was 56.5 ± 29.8 min/week. With a total satisfaction of 29.0 ± 3 points, the level of RCR was highly rated (3.85 ± 0.16 points) as a real solution to the problem associated with the presence of CVD (3.67 ± 0.34 points). DISCUSSION. The medical-technological solution TMP “IS-cardio”, combining the principles of traditional cardiac rehabilitation with telecardiology tools (monitoring based on digital recorders, automatic data transfer and feedback) met the criteria for the feasibility of using TMP with a similar concept. CONCLUSION. The high demand for remote monitoring, feasibility, and patient satisfaction of RCR may indicate the feasibility of its use for implementation of its programs.

Controllable Modulation of Trapped Carriers in Mechano/Thermo Dual‐Responsive Particles for Advanced Stress‐Encoded Information Storage

AbstractMechanoluminescence (ML) is a fascinating phenomenon with diverse applications in pressure sensing, damage detection, and stress distribution visualization. However, most ML materials exhibit instantaneous photon emission that requires real‐time recording with a photodetector, and thereby circumscribing their applicability predominantly to real‐time stress‐sensing scenarios. In this work, a novel method is introduced for non‐real‐time stress sensing utilizing Li0.1Na0.9NbO3:Pr3+ phosphor, which allows for the retrieval of pressure location and intensity even 20 days after the event. The influence of heat and pressure on the trap depth distribution is analyzed using thermoluminescence (TL) and ML measurements, and it is proved that both heat and pressure release the captured electrons in the same traps. Leveraging the intricate competition between mechanical and thermal detrapping processes, stress information can be accessed through TL imaging. Furthermore, an algorithm is proposed based on this phenomenon to authenticate the stress information. This research not only advances the fundamental understanding of ML phenomena but also introduces a novel approach for applications such as mechano‐history indicators, security papers, and advanced data storage systems.

Frequency of RPGRIP1 and MAP9 genetic modifiers of canine progressive retinal atrophy, in 132 breeds of dog.

Variants in RPGRIP1 and MAP9, termed RPGRIP1ins44 and MAP9del respectively, are both associated with a form of canine progressive retinal atrophy referred to as RPGRIP1-CRD and have both been demonstrated to modify the development and progression of this disease. In the current study both variants were genotyped in at least 50 dogs of 132 diverse breeds and the data reveal that both segregate in multiple breeds. Individually, each variant is common within largely non-overlapping subsets of breed, and there is a negative correlation between their frequencies within breeds that segregate both variants. The frequency of both variants exceeds 0.05 in a single breed only, the Miniature Longhaired Dachshund. These data indicate that both variants are likely to be ancient and predate the development and genetic isolation of modern dog breeds. That both variants are present individually at high frequency in multiple breeds is consistent with the hypothesis that homozygosity of either variant alone is not associated with a clinically relevant phenotype, whereas the negative correlation between the two variants is consistent with the application of selective pressure, from dog breeders, against homozygosity at both loci, probably due to the more severe phenotype associated with homozygosity at both loci.

Efficacy of Cricoid Pressure Application during Esophagogastroduodenoscopy in Patients with Poor Gastric Wall Extension

Introduction: Esophagogastroduodenoscopy (EGD) requires adequate air infusion. However, cases of poor gastrointestinal wall extension due to frequent eructation have been reported. Sufficient gastrointestinal wall extension can be achieved by applying cricoid pressure during EGD. Herein, we evaluated the frequency of cases with poor gastrointestinal wall extension and the efficacy and safety of applying cricoid pressure during EGD. Methods: This interventional study included patients who underwent EGD between January 2020 and December 2020 at the JA Akita Koseiren Yuri Kumiai General Hospital. Cases wherein folds of the greater curvature of the upper gastric body were not sufficiently extended during EGD were considered to have poor gastrointestinal wall extension. In such cases, air infusion was performed while applying cricoid pressure. This procedure was considered effective when gastric wall extension was achieved. Results: A total of 2,000 patients were enrolled and underwent upper gastrointestinal endoscopy; however, five were excluded because of upper gastrointestinal tract stenosis. Observation of gastric wall extension of the greater curvature in the upper gastric body with normal air insufflation was difficult in 113 (5.7%) cases. Applying cricoid pressure was effective in 93 (82.3%) patients with poor gastric wall extension. Sufficient gastric wall extension was achieved within an average of 12.8 s in cases where cricoid pressure application was effective. No adverse events were associated with cricoid pressure application. Conclusions: Cricoid pressure application for patients with poor gastric wall extension during EGD is useful for ensuring a sufficient field of view during observation of the gastric body.

Long‐time high‐pressure processing of a patatin‐rich potato proteins isolate: impact on aggregation and surface properties

SummaryIn this study, a 4% (w/w) dispersion of a commercial patatin‐rich potato protein isolate (Po‐PI) was pressurised at 400 MPa up to 48 h at 20 °C. Protein aggregation induced by high‐pressure processing (HHP) was followed by dynamic light scattering, intrinsic fluorescence (in‐situ or ex‐situ) or SAXS analysis. Surface properties (surface hydrophobicity and interfacial properties) of the HHP‐induced aggregates were also investigated. A gradual dimer dissociation/protein unfolding was observed under pressure. Po‐PI exhibited a slow relaxation time under pressure. Long‐time HHP (>4 h) induced significant modification of the Po‐PI protein structure with partial non‐reversible unfolding. After 48 h of pressurisation at 400 MPa, large aggregates (160 nm) were obtained and a monomodal distribution in intensity and in number frequency was observed indicating a controlled aggregation. Up to 24 h of pressurisation at 400 MPa, intermediate states were obtained after high‐pressure release. SDS‐PAGE profiles showed that HHP‐induced aggregation of Po‐PI was driven by non‐covalent interactions. All high‐pressure processed dispersions displayed a higher surface hydrophobicity as compared to non‐treated Po‐PI. Po‐PI dispersion treated for 8 h at 400 MPa presented the lowest adsorption rate, the highest final surface tension and formed the most rigid interfacial film. Po‐PI showed resistance to moderate pressure levels (400 MPa) and long pressure application times were required to induce significant protein denaturation/aggregation (≥24 h) and to optimally modify its interfacial properties (8 h).

Synthesis of PDMS Chain Structure with Introduced Dynamic Covalent Bonding for High‐Performance Rehealable Tactile Sensor Application

AbstractIn addressing the increasing demand for wearable sensing systems, the performance and lifespan of such devices must be improved by enhancing their sensitivity and healing capabilities. The present work introduces an innovative method for synthesizing a healable disulfide bond contained in a polydimethylsiloxane network (PDMS−SS) that incorporates ionic salts, which is designed to serve as a highly effective dielectric layer for capacitive tactile sensors. Within the polymer network structure, the cross‐linking agent pentaerythritol tetrakis 3‐mercaptopropionate (PTKPM) forms reversible disulfide bonds while simultaneously increasing polymer softness and the dielectric constant. The incorporation of dioctyl sulfosuccinate sodium salt (DOSS) significantly improves the capacitance and sensing properties by forming an electrical double‐layer through interactions between the electrode charge and salt ions at the contact interface. The developed polymer material‐based tactile sensor shows a strong response signal at low pressure (0.1 kPa) and maintains high sensitivity (0.175 kPa−1) over a wide pressure range (0.1–10 kPa). It also maintains the same sensitivity over 10 000 repeated applications of external pressure and is easily self‐healed against mechanical deformation due to the dynamic disulfide covalent bonding, restoring ≈95% of its detection capacity.

Numerical analysis-based performance assessment of the small-scale organic Rankine cycle turbine design for residential applications

The organic Rankine cycle (ORC) is one of the most common ways to use energy resources to utilise waste heat. Integrating ORC with other systems, such as cooling or heating applications, is also helpful for residential uses. In the ORC system, the turbines are the most critical component determining the system's efficiency. This study conducted a computational fluid dynamics study on a regenerative flow turbine that can be used in small-scale organic Rankine cycle systems. For the higher temperature applications, the analyses were performed using n-pentane working fluid for 1500 and 3000 rpm turbine speeds, inlet temperature between 475–550 K, outlet pressure between 0.9–1.2 MPa, and mass flow rates between 0.5–1.0 kg/s. As a result of the analysis, the isentropic efficiency varies between 4.97 % and 12.52 %. It was concluded that the output power obtained from the turbine varies between 0.53 kW and 2.96 kW. The analyses were also performed for lower temperature (363 and 393 K), pressure (0.05 MPa and 0.3 MPa) and mass flows (0.1 to 0.25 kg/s) applications. In this case, the isentropic efficiency of the turbine varies between 6.23 % and 14.52 %, whereas the power generation varies between 0.068 and 0.521 kW.

Long‐Term Heat‐Storage Ceramics based on Zr‐Substituted λ‐Ti3O5

AbstractHeat‐storage materials are important for energy saving to protect the environment. Here, we show a long‐term heat‐storage material based on zirconium‐substituted lambda‐trititanium‐pentoxide (λ‐ZrxTi3−xO5, 0 < x≤0.06). λ‐ZrxTi3−xO5 exhibits a phase transition to zirconium‐substituted beta‐trititanium‐pentoxide (β‐ZrxTi3−xO5) upon application of pressure. The transition pressures were 600 MPa (x=0.04) and about 1 GPa (x=0.06). When the pressure‐produced β‐phase is heated, the β‐phase returns to λ‐phase. The phase transition temperatures (i. e., heat‐storage temperatures) were 185 °C (458 K) and 183 °C (453 K) for x=0.04 and 0.06, respectively. These heat‐storage temperatures are suitable for the reuse of low‐temperature industrial waste heat, which is considered to be a difficult temperature region to be efficiently collected and reused. The present pressure‐sensitive heat‐storage ceramic, which can store the latent heat energy for a prolonged period, is effective for the sustainable reuse of heat energy that are wasted in power plants and industrial factories.

Flash viscous flow sintering of nanostructured amorphous ZrO2–Y2O3 composite ceramics starting from a partially amorphous precursor powder

Nanostructured amorphous composites are novel materials comprising nano-sized crystal phases embedded in an amorphous matrix, but often necessitating ultra-high-pressure molding for preparation. In this study, nanostructured amorphous ZrO2–Y2O3 composite ceramics were rapidly prepared for the first time using flash viscous flow sintering without the application of pressure. The relative density of the ZY ceramics increased with increasing current density, and ZY composite ceramics with relative density of 86%–97 % were prepared by FS in a short time of 60 s under 700 V/cm with 0.16–0.56 A/cm2. Furthermore, the sintering activities in FS were compared between partially amorphous powder and crystalline powder. The ceramics prepared by flash sintering of partially amorphous powder show a much higher relative density than that from crystalline powder, suggesting that partially amorphous powder achieves easier densification than crystalline powder in flash sintering under given current density and power dissipation. This phenomenon was attributable to the differing sintering mechanisms between the two materials, i.e., solid-state sintering for crystalline powder and viscous flow sintering for partially amorphous powder.

Uniformity of microbial injection for reinforcing saturated calcareous sand: A multi-test approach

The mineralization process of microbial-induced calcium carbonate precipitation (MICP) is influenced by many factors, and the uniformity of the calcium carbonate precipitation has become the main focus and challenge for MICP technology. In this study, the uniformity of the saturated calcareous sand treated with MICP was investigated through one-dimensional calcareous sand column tests and model tests. The coefficient of variation was employed in one-dimensional sand column tests to investigate the impact of injection rate, cementation solution concentration, and number of injection cycles on the uniformity of the MICP treatment. Additionally, model tests were conducted to investigate the impact of injection pressure and methods on the treatment range and uniformity under three-dimensional seepage conditions. Test results demonstrate that the reinforcement strength and uniformity are significantly influenced by the injection rate of the cementation solution, with a rate of 3 mL/min, yielding a favorable treatment effect. Excessive concentration of the cementation solution can lead to significant non-uniformity and a reduction in the compressive strength of MICP-treated samples. Conversely, excessively low concentrations may result in decreased bonding efficiency. Among the four considered concentrations, 0.5 mol/L and 1 mol/L exhibit superior reinforcing effects. The morphological development of calcareous sandy foundation reinforcement is associated with the spatial distribution pattern of the bacterial solution, exhibiting a relatively larger reinforcement area in proximity to the lower region of the model and a gradually decreasing range towards the upper part. Under three-dimensional seepage conditions, in addition to the non-uniform radial cementation along the injection pipe, there is also vertical heterogeneity of cementation along the length of the injection pipe due to gravitational effects, resulting in preferential deposition of calcium carbonate at the lower section. The application of injection pressure and a double-pipe circulation injection method can mitigate the accumulation of bacterial solution and cementation solution at the bottom, thereby improving the reinforcement range and uniformity.

Outcomes of Mastectomy and Immediate Reconstruction Managed with Closed-incision Negative Pressure Therapy Applied Over the Whole Breast.

Incision healing after mastectomy and immediate reconstruction can be supported with closed-incision negative pressure therapy (ciNPT). Studies have reported patients receiving postoperative care with ciNPT after breast surgery exhibited lower rates of dehiscence, infection, necrosis, and seroma, compared with standard dressings. A recent approach to ciNPT involves the application of negative pressure to the incision and a wider area of surrounding tissue. In this retrospective review, we investigated the outcomes of ciNPT using full-coverage dressings over the entire breast after mastectomy and reconstruction. Patients underwent mastectomies and immediate prepectoral breast reconstruction with an implant or tissue expander. After surgery, patients received oral antibiotics and ciNPT with full-coverage foam dressings at -125 mm Hg. All 54 patients (N = 105 incisions) were women, with a mean age of 53.5 years and 29.1 kg per m2 body mass index. Common comorbidities included prior chemotherapy (31.3%) or radiation (21.6%), hypertension (14.8%), and diabetes (5.6%). Procedures included skin-reducing (34.3%), skin-sparing (7.6%), and nipple-sparing (58.1%) mastectomies. Lymph nodes were removed in 38 (36.2%) incisions. All patients were discharged home with ciNPT on postoperative day (POD) 1, and ciNPT was discontinued on POD 5-7. At POD 30, three patients developed seromas, requiring revision. Of these, one required removal of the left tissue expander. The remaining 102 incisions (97.1%) healed without complication. Among this cohort, the use of ciNPT with full-dressing coverage of the breast incisions and surrounding soft tissue was effective in supporting incisional healing after mastectomy and immediate reconstruction.

Physiologic Validation of the Compensatory Reserve Metric Obtained From Pulse Oximetry Waveforms

Background: The compensatory reserve metric (CRM) provides a novel marker of hemodynamic status in prediction of sudden cardiovascular decompensation during central hypovolemia. The CRM has previously been calculated using arterial waveforms obtained from a photoplethysmographic volume-clamp technique. However, the in-field use of pulse oximetry is becoming more prominent in research and medicine. To improve in-field applicability of the CRM, this project aimed to validate pulse-oximetry derived CRM values relative to physiologic data during simulated hemorrhage through application of lower body negative pressure (LBNP). Methods: Forty-nine healthy adults (25 females) underwent a graded LBNP protocol with the following 5-minute stages: -0, -15, -30, -45, -60, -70, -80, -90, and 100 mmHg, or until the onset of pre-syncopal symptoms (tolerance) was reached. Arterial waveforms were sampled using pulse oximetry (Massimo Radical 7). The CRM was calculated using a validated one-dimensional convolutional neural network. A brachial artery catheter was used to measure intraarterial pressure. A 3-lead ECG was used to measure heart rate. SpO2 was measured using pulse oximetry. Cardiac output and stroke volume were estimated using the photoplethysmographic volume-clamp. Data were binned for the last thirty seconds of each completed stage, and at tolerance. Fixed-effect linear mixed models with repeated measures were used to examine the association between CRM values and physiologic variables. A priori significance was set at P<0.05. Results: The median LBNP stage reached was 70 mmHg (Range: 45-100 mmHg). Relative to baseline, at tolerance there was a 50±12% ( P<0.001) mean reduction in stroke volume, 65±27% ( P<0.001) increase in heart rate, 18±8% ( P<0.001) reduction in mean arterial pressure, 21±7% ( P<0.001) systolic blood pressure, 8±9% ( P<0.001) diastolic blood pressure, and 39±12% ( P<0.001) pulse pressure. The CRM obtained using pulse oximetry was significantly associated with a reduction in stroke volume ( P<0.001), increase in heart rate ( P<0.001), and reductions in systolic ( P=0.033), diastolic ( P=0.036), and pulse pressure ( P=0.002). There was no statistically significant association between CRM and cardiac output ( P=0.421), SpO2 ( P=0.408), or mean arterial pressure ( P=0.214). Conclusion: The CRM obtained using pulse oximetry may be a valid, reliable marker of hemodynamic status with promising in-field applications. Future studies warrant investigation of feasibility and applicability within various contexts ranging from the operating room to the battlefield. The presented work was funded in part by the Congressionally Directed Medical Research Program (Award No. DM180240) and Offce of Naval Research (Awards No. N00014-18-D-7001 and N00014-19-C-2017). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Identification of Bacterial Species Capable of Degrading LDPE

Abstract: The Plastic is polymeric material having capability of being molded or shaped by the application of heat and pressure. The low-density polyethylene(LDPE) is the type of plastic which is used in various purpose of our daily life. It is one of the major environmental problems because of its slow degradation rate .To control the pollution caused by low-density polyethylene, microbes are isolated from the dumping site of the Durg region of Chhattisgarh. These microbes are screened by the zone of clearance method for degradation of low-density polyethylene using PEG as substrate. The screened microbes were identified by morphological and biochemical characteristics.Nine bacterial isolates was selected for biodegradation studies.Confirmation of bacterial biodegradation of low-density polyethylene was performed by using weight loss measurement and pH change due to production of acidic product.One potential isolate were further identified through 16S rRNA sequences Alcaligenes faecalis was shown the high degradation rate of low-density polyethylene

Intrinsically stretchable jellyfish-like gold nanowires film as multifunctional wearable chemical and physical sensors

We report on an intrinsically stretchable jellyfish-like gold nanowires film as a multifunctional wearable platform that can detect both chemical and physical biometrics. The film inherently exhibits multifunctionality, serving directly as an electrochemical electrode, strain sensor, temperature sensor, pressure sensor, and noncontact humidity sensor without the need of any additional materials. Our results highlight the excellent electrochemical properties, evidenced by a large electrochemical active surface area (EASA) of approximately 22.39 cm2 and the ability to withstand significant strain values up to 70 %. Leveraging these attributes, a stretchable electrochemical glucose biosensor was further designed with high sensitivity (45.40μA·mM−1·cm−2) and low limit of detection (10 μM). In addition, its sensing applications in strain, temperature, pressure and noncontact humidity were systematically explored. Impressively, the gold film is capable of monitoring multiple human motions and physiological signals, including joints bending, pulse motions, throat motions (e.g., drinking, speaking, swallowing and pronunciation recognition) and breathing. Furthermore, the film exhibited great versatility by integrating with 3D printing hydrogels, enabling customized patterning. The results demonstrate that our gold nanowires coating approach represent a new route to design multimodal soft wearable platforms for applications in personalized medicine and next-generation healthcare systems.

Ab-initio investigation of the structural, electronic and optical properties of CsPbBr3 perovskite under pressure using the DFT-1/2 method

Pressure-induced phase transitions in metal halide perovskites lead to significantly different material properties and offer great potential for diverse applications. The electronic, structural, and optical properties of Cesium lead bromide (CsPbBr3) crystals are investigated using density functional theory (DFT) to draw an integrated picture of orbital morphology, absorption spectra, and band gap values. Spin-orbit coupling and DFT-1/2 correction are used to gain a better insight into electronic properties and band splitting in the cubic phase. Calculations of pressure-induced phase transitions, electronic band gap engineering, and manipulation of optical absorption edges of CsPbBr3 are conducted. In the cubic and tetragonal crystal lattices, a band gap closure and opening occurs demonstrating a Dirac cone upon application and increase of pressure. Indeed, in the tetragonal lattice of CsPbBr3, a topological band occurs. Orthorhombic perovskite crystal lattice undergoes successive direct-indirect and indirect-direct band gap transitions, followed by a space group change at extreme pressures. However, under pressure, orthorhombic non-perovskite lattice experiences a sudden band gap breakdown. Phase and band gap transitions are explained by orbital hybridizations and structural symmetry evolution (e.g., bond length contraction/dilation and octahedral cage rotation/distortion). These results provide comprehensive guidelines for further experimental studies on pressure engineering, advanced photovoltaic and optoelectronic applications, discovering and understanding new topological band structures of perovskite materials.

4f electron temperature driven ultrafast electron localization

Valence transitions in strongly correlated electron systems are caused by orbital hybridization and Coulomb interactions between localized and delocalized electrons. The transition can be triggered by changes in the electronic structure and is sensitive to temperature variations, applications of magnetic fields, and physical or chemical pressure. Launching the transition by photoelectric fields can directly excite the electronic states and thus provides an ideal platform to study the correlation among electrons on ultrafast timescales. The EuNi2(Si0.21Ge0.79)2 mixed-valence metal is an ideal material to investigate the valence transition of the Eu ions via the amplified orbital hybridization by the photoelectric field on subpicosecond timescales. A direct view on the 4f electron occupancy of the Eu ions is required to understand the microscopic origin of the transition. Here we probe the 4f electron states of EuNi2(Si0.21Ge0.79)2 at the sub-ps timescale after photoexcitation by x-ray absorption spectroscopy across the Eu M5-absorption edge. The observed spectral changes due to the excitation indicate a population change of total angular momentum multiplet states J = 0, 1, 2, and 3 of Eu3+ and the Eu2+ J = 7/2 multiplet state caused by an increase in 4f electron temperature that results in a 4f localization process. This electronic temperature increases combined with fluence-dependent screening accounts for the strongly nonlinear effective valence change. The data allow us to extract a time-dependent determination of an effective temperature of the 4f shell, which is also of great relevance in the understanding of metallic systems' properties, such as the ultrafast demagnetization of ferromagnetic rare-earth intermetallic and their all-optical magnetization switching. In addition, our results elucidate the energetics of charge fluctuations in valence-mixed electronic systems, which provide enriched knowledge regarding the role of valence transitions and orbital hybridization for quantum critical phenomena. Published by the American Physical Society 2024