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Preserving stable tooth-periodontal tissue integration is vital for maintaining alveolar bone stability under physiological conditions. However, tooth extraction compromises this integration and impedes socket healing. Therefore, it becomes crucial to provide early stage coverage of the socket to promote optimal healing. Drawing inspiration from the periodontium, we have developed a quaternized methacryloyl chitosan/dopamine-grafted oxidized sodium alginate hydrogel, termed the quaternized methacryloyl chitosan/dopamine-grafted oxidized sodium alginate hydrogel (QDL hydrogel). Through blue-light-induced cross-linking, the QDL hydrogel serves as a comprehensive wound dressing for socket healing. The QDL hydrogel exhibits remarkable efficacy in closing irregular tooth extraction wounds. Its favorable mechanical properties, flexible formability, and strong adhesion are achieved through modifications of chitosan and sodium alginate derived from biomass sources. Moreover, the QDL hydrogel demonstrates a superior hemostatic ability, facilitating swift blood clot formation. Additionally, the inherent antibacterial properties of the QDL hydrogel effectively inhibit oral microorganisms. Furthermore, the QDL hydrogel promotes angiogenesis, which facilitates the nutrient supply for subsequent tissue regeneration. Notably, the hydrogel accelerates socket healing by upregulating the expression of genes associated with wound healing. In conclusion, the periodontium-mimicking multifunctional hydrogel exhibits significant potential as a clinical tooth extraction wound dressing.

Abstract. Demand for many products may depend on the price of a tradable asset or on the economy in general. For example, demand for equipment that plants or harvests corn [...]

De novo pyrimidine biosynthesis is achieved by cytosolic carbamoyl-phosphate synthetase II, aspartate transcarbamylase and dihydroorotase (CAD) and uridine 5′-monophosphate synthase (UMPS), and mitochondrial dihydroorotate dehydrogenase (DHODH). However, how these enzymes are orchestrated remains enigmatical. Here we show that cytosolic glutamate oxaloacetate transaminase 1 clusters with CAD and UMPS, and this complex then connects with DHODH, which is mediated by the mitochondrial outer membrane protein voltage-dependent anion-selective channel protein 3. Therefore, these proteins form a multi-enzyme complex, named ‘pyrimidinosome’, involving AMP-activated protein kinase (AMPK) as a regulator. Activated AMPK dissociates from the complex to enhance pyrimidinosome assembly but inactivated UMPS, which promotes DHODH-mediated ferroptosis defence. Meanwhile, cancer cells with lower expression of AMPK are more reliant on pyrimidinosome-mediated UMP biosynthesis and more vulnerable to its inhibition. Our findings reveal the role of pyrimidinosome in regulating pyrimidine flux and ferroptosis, and suggest a pharmaceutical strategy of targeting pyrimidinosome in cancer treatment.

The conflict between climate change and energy scarcity has recently gained widespread attention. The development and promotion of green power and renewable energy is an efficient strategy to address this issue. The widespread use of distributed renewable energy in microgrids results in decentralized power supply. The features of distributed power trading, such as low single transaction volume and frequent transaction intervals, present both possibilities and problems to the green electricity market. The usual centralized control and selling of power are no longer appropriate in this circumstance. This study proposes a decentralized energy transaction system architecture in the microgrid and connects the double auction mechanism to achieve the interests of each participant based on blockchain technology and the status quo green power trade in China. Finally, using the trading strategy and model, this study constructs a real and operational energy trading platform, and simulated experiments demonstrate the dependability and efficacy of the proposed trading mechanism.

Pneumatic soft actuators can change their shapes under pneumatic pressure actuation and are capable of continuous bending. However, the air chambers inside will expand during the actuation process and cause nonlinear problems. Therefore pneumatic actuators are difficulties to model. In this paper, three types of bending actuators with different air chamber shapes are designed and the finite element model (FEM) is developed to simulate the deformation under different air pressure actuation. A prototype of the bending actuator is fabricated and a method to limit the expansion of the air chamber is designed based on the FEM results, which can effectively improve the expansion and the response of the actuator under low air pressure conditions through experimental comparison.

In this study, we design and fabricate a fully flexible angular displacement sensor and a corresponding fish-shaped soft pneumatic actuator. We describe the design and fabrication process of the sensor and fabricate a corresponding physical object to apply it to the soft pneumatic actuator. Material experiments with silicone rubber were also conducted to obtain the linear relationship in its small deformation range. Through the theoretical analysis of the designed angular displacement sensor, a linear relationship between the bending angle of the soft pneumatic actuator and the resistance of the angular displacement sensor was obtained. And a bending angle visual measurement platform was built for experimental verification. The results show that the experimental results are consistent with the theory, and the designed angular displacement sensor has a good linear relationship when applied to a fish-shaped soft pneumatic actuator.

The fatigue properties of titanium alloy short-stems with four different lengths, manufactured by electron beam melting (EBM) technology, were investigated by in vitro test and finite element (FE) analysis. FE simulation results indicate that the maximum tensile stress concentrates at the lateral side of the stem body. The magnitude of the concentrated tensile stress increases and the corresponding area of the axial section decreases with increasing of stem length. Results from fatigue tests demonstrate that fatigue cracks mainly initiate from the rough surface of the stem where the maximum tensile stress concentrates. The fatigue strength decreases with the increase of stem length, which is attributed to the higher stress concentration on the longer stem surface. In addition, it is found that post EBM treatment via hot isostatic processing (HIP) is able to enhance the fatigue properties of the stems, since the pores generated during EBM are mostly closed during HIP. Our work also demonstrates that the stress concentration on the stem surface can be effectively mitigated and the corresponding fatigue properties of the EBM-fabricated titanium alloy short stem can be considerably improved by optimizing the design in the stem length. [ABSTRACT FROM AUTHOR]

Purpose: Analyses of the morphology of proximal femora are essential for preoperative planning and designing customized femoral stems in total hip arthroplasty as well as intramedullary nailing fixation. Various studies reported measurements and analyses on the general geometry of proximal femora three-dimensionally. However, the modeling and measurements are time-consuming and unfriendly to surgeons. Thus, automated measurement and modeling of the femoral medullary canal are critical to promote the clinical application. Methods: An approach to automated measuring morphological parameters of proximal femur was proposed, and a software allowing importing femur models and manually locating the related anatomic landmarks was developed in the current study. 3D modeling of the femoral medullary canal was created by the semispherical iterative searching algorithm, and 16 key anatomic parameters of the proximal femur were automatically calculated by the least-squares fitting algorithm. Results: By experimenting on 196 femur STL models, the average execution time of single measurement was 0.88 (SD = 0.13) s, and the intra-class correlation coefficient of 10 anatomic parameters was between 0.880 and 0.996, showing high intra-rater and inter-rater reliability. Conclusions: The parameters of proximal femur can be easily measured, and the 3D modeling of the femoral medullary canal can be rapidly achieved. The approach will be easily applicable to clinical practice and has the potential to be applied in the design of customized femoral stems.

Packaged fresh spinach has been associated with outbreaks of illness caused by Escherichia coliO157:H7. The purpose of this study was to assess the behavior of E. coliO157:H7 in packaged baby spinach in response to storage conditions of temperature and package atmosphere and including effects of inoculation level, spinach leaf damage (cut leaves), internalized or leaf surface contamination, exposure to hypochlorite sanitizer, and package size. Behavior of E. coliO157:H7 inoculated at 2 and 4 log CFU/g on spinach packaged in polymer bags composed of a two-layer laminate (polypropylene and polyethylene) and stored under atmospheres of 20% O2–3% CO2and 0% O2–15% CO2(aerobic and anaerobic, respectively) was assessed at 5, 7, 12, and 15°C for up to 14 days. Growth kinetics were calculated using DMFit software. Temperature decreases progressively diminished growth or survival of the pathogen, and an aerobic package atmosphere resulted in longer lag times (4 to 6 days) and lower population levels (0.2 to 1.4 log CFU/g) compared with the anaerobic atmosphere at 15°C. Internalized contamination, leaf cuts, or exposure to 100 ppm of hypochlorite did not result in changes in pathogen behavior compared with controls; however, a growth minimization trend consisting of longer lag times and lower population levels was repeatedly observed in the aerobic compared with the anaerobic package atmospheres. In contrast, growth of indigenous mesophiles and Enterobacteriaceaewas unaffected by package atmosphere. Spinach stored at 5 to 7°C in two sizes (5 and 16 oz) of polyethylene terephthalate clamshell packages with ambient air atmospheres was more likely to progress to lower-oxygen conditions in 16-oz compared with 5-oz packages after 7 days of storage (P< 0.05). Practices to maintain aerobic conditions within the package, as well as storage of the package at low temperature, are ways to limit growth of E. coliO157:H7 in packaged spinach.

Baicalin is the main flavonoid from the roots of an important medicinal plant, Scutellaria baicalensis, which shows a variety biological activities. Psoriasis is a chronic immune-mediated inflammatory disease that affects the skin. The unmet need of psoriasis is that many patients do not respond adequately to available clinical treatment. In this study, we found that baicalin showed inhibited dermal inflammation in a murine model of psoriasis via topical application of imiquimod. After a 5-day topical imiquimod application, baicalin or the control vehicle cream was to applied to the lesions of BALB/c mice for a further 4 days. The erythema, scaling, and thickness of the epidermal layer significantly improved in the baicalin-treated mice. The levels of interleukin-17A, interleukin-22, interleukin-23, and tumor necrosis factor in the skin significantly decreased after baicalin treatment. Baicalin also inhibited imiquimod-induced interleukin-17A production in skin draining lymph node cells. The infiltration of γδ T cells into the skin lesions induced by imiquimod was also suppressed after baicalin treatment. These results suggest that baicalin inhibited skin inflammation through the inhibition of the interleukin-17/interleukin-23 axis in a murine model of psoriasis. [ABSTRACT FROM AUTHOR]

The serious cytotoxicity of tyramine attracted marked attention as it induced necrosis of human intestinal cells. This paper presented a novel and facile high performance thin-layer chromatography (HPTLC) method tailored for screening tyramine in cheese. Separation was performed on glass backed silica gel plates, using methanol/ethyl acetate/ammonia (6/4/1 v/v/v) as the mobile phase. Special efforts were focused on optimizing conditions (substrate preparation, laser wavelength, salt types and concentrations) of surface enhanced Raman spectroscopy (SERS) measurements directly on plates after derivatization, which enabled molecule-specific identification of targeted bands. In parallel, fluorescent densitometry (FLD) scanning at 380

The present work studied the simultaneous separation of H2S and CO2from biogas by gas–liquid membrane contactor (GLMC) using single and mixed absorbents. The synthetic biogas contained 300 to 900 ppm of H2S, 30% to 50% CO2and CH4. To better understand the effects of different absorbents on simultaneous separation of H2S and CO2from biogas, water, monoethanolamine (MEA, primary amine), potassium carbonate (K2CO3, inorganic salt), potassium hydroxide (KOH, inorganic salt), and potassium sarcosine (PS, organic salt) were applied as absorbent solutions. Poly(vinylidene fluoride) (PVDF) hollow fiber membrane was used in the membrane contactor modules. The simultaneous absorption performance of CO2and H2S into single and mixed absorbents was investigated. In addition, the effects of liquid and gas velocities, absorbent concentration, acid gas content of the feed gas, and gas pressure on the absorption performance and the analysis of mass transfer coefficients were investigated. The results indicated that the highest H2S absorption flux was obtained when KOH and K2CO3were used as single absorbents, and the highest CO2flux was obtained using PS as the single absorbent. The use of promoted K2CO3with PS solutions could simultaneously improve the absorption flux of H2S and CO2. Increasing the liquid flow rate and absorbent concentration led to an increase in the CO2absorption flux, while increasing the gas flow rate led to a significant increase in H2S absorption; The change of liquid flow rate has little effect on H2S absorption flux. A long-term stability test revealed that partial wetting of membrane could reduce the CO2absorption flux but has little effect on H2S absorption flux. The detailed analysis of the mass transfer coefficients showed that liquid side resistance was negligible in comparison with membrane and gas side resistances for H2S absorption. On the contrary, the mass transfer process of CO2was controlled by liquid mass transfer resistance.

In this paper, the seismic behavior of partially encased concrete columns and steel beam connection are studied, which contains 4 different structures of beam-column joints. By applying a low cycle loading, the failure modes and the strain distribution of each connected component plate domain were studied. The effect of the end plate thickness, stiffened plate, and back plate on the node bearing capacity, stiffness and ductility was analyzed. The bearing capacity of the specimen is improved with the end plate thickness increases, and a lot increased with setting the back plate.

This paper proposes imaging with 3-dimensional vibroacoustography for postoperatively assessing the uncovered cup area after total hip arthroplasty as a quantitative criterion to evaluate implant fixation.

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In this study, we design and fabricate a fully flexible angular displacement sensor and a corresponding fish-shaped soft pneumatic actuator. We describe the design and fabrication process of the sensor and fabricate a corresponding physical object to apply it to the soft pneumatic actuator. Material experiments with silicone rubber were also conducted to obtain the linear relationship in its small deformation range. Through the theoretical analysis of the designed angular displacement sensor, a linear relationship between the bending angle of the soft pneumatic actuator and the resistance of the angular displacement sensor was obtained. And a bending angle visual measurement platform was built for experimental verification. The results show that the experimental results are consistent with the theory, and the designed angular displacement sensor has a good linear relationship when applied to a fish-shaped soft pneumatic actuator.

Pneumatic soft actuators can change their shapes under pneumatic pressure actuation and are capable of continuous bending. However, the air chambers inside will expand during the actuation process and cause nonlinear problems. Therefore pneumatic actuators are difficulties to model. In this paper, three types of bending actuators with different air chamber shapes are designed and the finite element model (FEM) is developed to simulate the deformation under different air pressure actuation. A prototype of the bending actuator is fabricated and a method to limit the expansion of the air chamber is designed based on the FEM results, which can effectively improve the expansion and the response of the actuator under low air pressure conditions through experimental comparison.

The inactivation and conformational changes of the bacterial chaperonin GroEL have been studied in SDS solutions with different concentrations. The results show that increasing the SDS concentration caused the intrinsic fluorescence emission intensity to increase and the emission peak to slightly blue-shift, indicating that increasing the SDS concentration can cause the hydrophobic surface to be slightly buried. The changes in the ANS-binding fluorescence with increasing SDS concentration also showed that the GroEL hydrophobic surface decreased. At low SDS concentrations, less than 0.3 mM, the GroEL ATPase activity increased with increasing SDS concentration. Increasing the SDS concentration beyond 0.3 mM caused the GroEL ATPase activity to quickly decrease. At high SDS concentrations, above 0.8 mM, the residual GroEL ATPase activity was less than 10% of the original activity, but the GroEL molecule maintained its native conformation (as indicated by the exposure of buried thiol groups, electrophoresis, and changes of CD spectra). The above results suggest that the conformational changes of the active site result in the inactivation of the ATPase even though the GroEL molecule does not markedly unfold at low SDS concentrations.

The conformational changes of penaeus penicillatus acid phosphatase during denaturation in guanidine hydrochloride solutions were studied by following changes in the intrinsic fluorescence, ultraviolet difference absorption, and circular dichroism spectra. Inactivation of the enzyme in guanidine hydrochloride solutions were compared with unfolding of the enzyme molecule. The results show that the extent of unfolding in guanidine solutions measured by several different methods closely coincide with each other and that slightly lower concentrations of guanidine are required to bring about inactivation than are required to produce significant conformational changes of the enzyme molecule. At the same concentrations, the inactivation rate constants are markedly faster than the rate constants for unfolding of the enzyme. The above results suggest that the active sites of this enzyme display more conformational flexibility than the enzyme malecule as a whole.

Subchondral bone marrow lesions (BMLs) are common magnetic resonance imaging (MRI) features in joints affected by osteoarthritis (OA), however, their clinical impacts and mechanisms remain controversial. Thus, we aimed to investigate subchondral BMLs in knee OA patients who underwent total knee arthroplasty (TKA), then evaluate the associations of osteoclastogenesis and nerve growth in subchondral BMLs with clinical symptoms.

To evaluate accuracy of an innovative “Skywalker” system, a newly designed, robot-assisted operation system for orthopaedics via a clinical trial at knee joint.

Background: Knee osteoarthritis (OA) is a common disabling disease involving the entire joint tissue, and its onset and progression are affected by many factors. However, the current number of studies investigating the relationship between subchondral trabecular bone (STB), knee alignment, and OA severity is limited. We aimed to investigate the variation in tibial plateau STB microarchitecture in end-stage knee OA patients and their association with knee alignment (hip-knee-ankle, HKA, angle) and OA severity. Methods: Seventy-one knee OA patients scheduled for total knee arthroplasty (TKA) underwent preoperative radiography to measure the HKA angle and Kellgren-Lawrence grade. Tibial plateaus collected from TKA were scanned using micro-computed tomography to analyze the STB microarchitecture. Histological sections were used to assess cartilage degeneration (OARSI score). Correlations between the HKA angle, OA severity (OARSI score, Kellgren-Lawrence grade), and STB microarchitecture were evaluated. Differences in STB microstructural parameters between varus and valgus alignment groups based on the HKA angle were examined. Results: The HKA angle was significantly correlated with all STB microarchitecture parameters (p&lt; 0.01). The HKA angle was more correlated with the medial-to-lateral ratios of the microarchitecture parameters than with the medial or lateral tibia plateaus. The HKA angle and all STB microarchitecture parameters are significantly correlated with both the OARSI score and Kellgren-Lawrence grade (p&lt; 0.01). Conclusions: The STB microarchitecture is associated with the HKA angle and OA severity. With the increase of the knee alignment deviation and OA severity, the STB of the affected side tibial plateau increased in bone volume, trabecular number, and trabecular thickness and decreased in trabecular separation.

Reports that the Pearl River Delta, one of China's most important areas and regional forerunner of modernization in Guangdong province, is groomed to be a financial corridor. Massive project under way in the Pearl River Delta; Economic development rate of the Pearl River Delta; Goals for overall development of the financial sector in the Pearl River Delta between 1996 and 2000.

The article reports on a study which explored the antioxidative effects of yam or sweet potato in liver. It states that researcher evaluated the hepapropective effect of the 70W35 strain of Taiwanese yams in the model of CCl4-induced hepatic fibrosis in rats. The study found that yam-treated rats had reduced cirrhosis, level of gamma glutaminotranspeptidase and low-density lipoprotein, and triglyceride.