A Green High-k Dielectric from Modified Carboxymethyl Cellulose-Based with Dextrin.

Many crucial components inside electronic devices are made from non-renewable, non-biodegradable, and potentially toxic materials, leading to environmental damage. Finding alternative green dielectric materials is mandatory to align with global sustainable goals. Carboxymethyl cellulose (CMC) is a bio-polymer derived from cellulose and has outstanding properties. Herein, citric acid, dextrin, and CMC based hydrogels are prepared, which are biocompatible and biodegradable and exhibit rubber-like mechanical properties, with Young modulus values of 0.89 MPa. Hence, thin film CMC-based hydrogel is explored as a suitable green high-k dielectric candidate for operation at low voltages, demonstrating a high dielectric constant of up to 78. These fabricated transistors reveal stable high capacitance (2090 nF cm-2) for ≈±3 V operation. Using a polyelectrolyte-type approach and poly-(2-vinyl anthracene) (PVAn) surface modification, this study demonstrates a thin dielectric layer (d ≈30 nm) with a small voltage threshold (Vth ≈-0.8 V), moderate transconductance (gm ≈65 nS), and high ON-OFF ratio (≈105). Furthermore, the dielectric layer exhibits stable performance under bias stress of ± 3.5 V and 100 cycles of switching tests. The modified CMC-based hydrogel demonstrates desirable performance as a green dielectric for low-voltage operation, further highlighting its biocompatibility.

A novel fluffy PLGA/HA composite scaffold for bone defect repair.

Treatment of bone defects remains crucial challenge for successful bone healing, which arouses great interests in designing and fabricating ideal biomaterials. In this regard, the present study focuses on developing a novel fluffy scaffold of poly Lactide-co-glycolide (PLGA) composites with hydroxyapatite (HA) scaffold used in bone defect repair in rabbits. This fluffy PLGA/HA composite scaffold was fabricated by using multi-electro-spinning combined with biomineralization technology. In vitro analysis of human bone marrow mesenchymal stem cells (BMSCs) seeded onto fluffy PLGA/HA composite scaffold showed their ability to adhere, proliferate and cell viability. Transplant of fluffy PLGA/HA composite scaffold in a rabbit model showed a significant increase in mineralized tissue production compared to conventional and fluffy PLGA/HA composite scaffold. These findings are promising for fluffy PLGA/HA composite scaffolds used in bone defects.

[Pharmacokinetics and brain distribution of NMD/TMP-nanoparticles].

This study aims to prepare nimodipine/tetramethylpyrazine-loaded poly(D, L-lactide-co-glycolide) dual-drug nanoparticles (NMD/TMP-NPs) and investigate pharmacokinetics and brain distribution to evaluate the possibility of enhancing the drug effect of dual-drug nanoparticles. NMD/TMP-NPs were prepared via W/O/W emulsion solvent evaporation. Entrapment efficiency and drug loading of NMD/TMP-NPs were investigated by ultracentrifugation, and drug release behavior in vitro was studied by dialysis method. The pharmacokinetic and brain distribution were studied in SD mice administered intravenously with NMD/TMP-NPs in comparison with NMD-suspension, NMD/TMP-suspension and NMD-NPs, (NMD-NPs+TMP)-suspension. According to the results, the entrapment efficiency and drug loading of NMD were (79.71±0.73)%, (1.74±0.02)%, those of TMP were (40.26±1.51)% and (4.38±0.16)%. The nanoparticles showed the property of sustained release. On the basis of the major parameters for in vivo pharmacokinetic and brain distribution, t1/2ß of NMD-suspension, NMD/TMP-suspension and NMD-NPs, (NMD-NPs+TMP)-suspension, NMD/TMP-NPs were (1.097±0.146), (1.055±0.06), (1.950±0.140), (1.860±0.096), (2.497±0.475） h, CL were (0.778±0.098), (1.133±0.111), (0.247±0.023), (0.497±0.040), (0.297±0.024) h•L-1, AUC0-t in rat plasma were (514.218±60.383), (352.916±33.691), (1 618.429±240.198), (804.110±75.804), (1 349.058±215.497) µg•h•L⁻¹, respectively, and AUC0-t in brain were 0.301 9, 0.624 8, 1.068 6, 1.313 0, 1.046 5 mg•h•L⁻¹, respectively. According to the in vivo study, the pharmacokinetic behavior of NMD were markedly prolonged by adding TMP or prepared dual-drug nanoparticles.

[Treatment of penile strangulation and sexual psychological analysis of the patients].

OBJECTIVE: To find the best treatment of penile strangulation and to analyze the sexual psychological factors of the patients. METHODS: We retrospectively analyzed the experiences in removing foreign objects around the penis in 21 patients aged 19 - 61 years with the strangulation time varying from 10 hours to 4 days. The objects were mostly made of metal or plastics. RESULTS: All the objects were successfully removed, 5 of them with the help of lubricant, 4 by aspirating the corpus cavernosum, 8 by shipping with pliers, 2 with the diamond-tipped dental drill, and the other 2, which virtually defied cutting, by aspirating the corpus cavernosum following degloving surgery. CONCLUSION: In removing foreign objects around the penis, simpler methods should be given precedence over more complex ones, and for those that virtually defy cutting, the best option is degloving surgery with particular attention to the survival of the penile skin flap.

Application of Quality Control Circle in Promoting the Use of Rubber Dams in the Root Canal Treatment of Primary Teeth.

OBJECTIVE: Study the effect of quality control circle (QCC) in promoting the usage of rubber dams (RD) in root canal treatment of chronic pulpitis in primary teeth. METHODS: Set up a quality control group to increase the amount of rubber dams used in the treatment of chronic pulpitis in primary teeth. Monthly monitoring results of the usage amount were counted by the outpatient computer system. Relevant data were collected through questionnaires, and causes of low utilization were analyzed, and the improvement measurements were formulated and implemented. Quality control circle activity was evaluated. RESULTS: Through the quality control circle activity, the consumption of rubber dams in the root canal treatment of chronic pulpitis was significantly improved, children in treatment became more cooperative, and operation time of root canal treatment has also been shortened. CONCLUSION: The quality control circle activities played a significant role in promoting the use of rubber dams in the root canal treatment of primary teeth, and it can be used as a method to promote new clinical treatment programs.

A comparative study on membrane fouling alleviation mechanisms by using nanoscale Fe3O4 and poly dimethyldiallylammonium chloride.

Membrane bioreactor (MBR) has become a promising technology for wastewater treatment. However, membrane fouling frequently occurred which greatly increased operational expense. Two different membrane fouling alleviation mechanisms were explored in this study. Addition of poly dimethyldiallylammonium chloride (PDMDAAC) facilitated formation of flocs-flocs aggregates, which were more adaptable to the changing environment, resulting in less soluble microbial products (SMP) secretion. However, PDMDAAC lose activity gradually, and had a less sustainable effect on membrane fouling alleviation. Nanoscale Fe3O4 was applied to alleviate membrane fouling, and membrane sustainable filtration cycle extended 2-fold compared to the control group. Results showed that dehydrogenase activity in the reactor with optimal addition of nanoscale Fe3O4 increased 2.86 ± 0.11 times compared to control group. SMP (especially tryptophan protein-like substances) decreased to 9.79 ± 1.34 mg L-1 with the addition of nanoscale Fe3O4, which was lower than that in the control group (15.31 ± 0.53 mg L-1). It's speculated that nanoscale Fe3O4 performed as conductive material, which intensified interspecies electron transfer. The sludge dehydrogenase activity was then enhanced, which facilitated the utilization and microbial degradation of SMP, suppressing membrane fouling consequently.

Impact of poly dimethyldiallylammonium chloride on membrane fouling mitigation in a membrane bioreactor.

Poly dimethyldiallylammonium chloride (PDMDAAC) was applied in a membrane bioreactor (MBR) to study its effects on mitigation of MBR membrane fouling. Floc size, zeta potential, soluble microbial substances (SMP) and extracellular polymeric substances (EPS) secretion were studied with respect to PDMMAAC-dosing operations. Results demonstrated that a sustainable filtration cycle extended 3.3 times with the optimal PDMDAAC dosage of 90 mg L-1. The addition of PDMDAAC could increase zeta potential of sludge floc, which led to the decrease in repulsive electrostatic interactions between flocs, as well as the facilitation of flocs-to-flocs aggregation. With the optimal dosage of PDMDAAC, the mean size of sludge was 3.23 ± 0.55 times higher than the control group, resulting in higher impact resistance and better adaptive capacity to the changing environment, which led to less SMP secretion. Moreover, a high contaminants removal rate was achieved in the reactor that was dosed with PDMDAAC. The average effluent concentrations of chemical oxygen demand and total nitrogen were less than 45.6 ± 2.85 and 5.23 ± 0.61 mg L-1, respectively, and the corresponding removal rates were 93.1 ± 5.81% and 89.1 ± 9.61%.

[Foreign body aspiration and ingestion during oral disease treatment].

Foreign body aspiration and ingestion during oral disease treatment are possible to occur. The incidence is prone to take place among children. Extracted teeth, endodontic instruments, prosthesis, and orthodontic appliance items are possible to be aspirated or swallowed. This article summarizes the reasons, handling methods, and prevention of foreign body aspiration and ingestion to provide guidance for clinical work.

Dental follicle cells combined with beta-tricalcium phosphate ceramic: a novel available therapeutic strategy to restore periodontal defects.

Tissue-engineering strategies to restore the periodontal defects are being developed. It will result in the periodontal formation and growing new function tissue rather than new replacement of periodontium. Although a number of procedures have been investigated in an attempt to regenerate lost periodontal tissue, none has yet led to new cementum formation, remodeling of the periodontal ligament, and new bone formation in clinic. Dental follicle cells (DFCs), as a progenitor cell of periodontal ligament cell and stem cell, have more potential abilities than PDL-cell in formation of periodontal tissue. More researches focus on the inductive environments, such as bone morphogenetic protein-2 (BMP-2), dexamethasone, and transfer growth factor, and scaffold. We hypotheses that DFCs from Beagle's dog are isolated, induced by BMP-2, basic-fibroblast growth factor and dexamethasone, and seeded by beta-tricalcium phosphate ceramic (beta-TCP), then the complex was auto-implanted into the periodontal defects in the same Beagle's dog to observe the regeneration of periodontal tissue in vivo. The study will explore the feasibility and application of restore of periodontal defects by DFCs-beta-TCP complex. We believe it is especially helpful to future clinical study and application.