Transformation behavior of hazardous jarosite into recyclable hematite in a solution with high concentrations of K+ and Na.

Iron in the leaching solution with high K+ and Na+ concentrations was usually precipitated as the typical hazardous and toxic jarosite residues. However, this method of treatment has been greatly restricted by increasingly strict environmental regulations. Here we propose that iron can be precipitated from the solution with high K+ and Na+ concentrations as recyclable hematite products by adjusting the concentration ratio of sodium and potassium ions in the solution. The transformation behavior of jarosite into hematite in high concentration potassium ion and sodium ion solution was explained based on collision theory. The results indicated that in instances where the concentration ratio of Na+/K+ is ≥ 4:1, the iron present in the solution can be effectively precipitated as a recyclable hematite product, as opposed to forming the conventional hazardous jarosite residue, even under conditions where the potassium ion concentration reaches levels as high as 4 g/L. On the other hand, thermodynamic and molecular dynamics simulations indicate that at a temperature of 185 °C, the decomposition transformation of Na-jarosite (32.64 kJ and 7.25 eV) is more energetically advantageous compared to that of K-jarosite (61.07 kJ and 15.31 eV). The results were verified by the leaching solution from smelting industry. The iron content in the residues is above 58%, the sulfur content is below 4%, the zinc content is below 1%, and the total iron concentration in the supernatant is about 4 g/L, reaching the production index of the smelting industry. The green, environmentally friendly, and recyclable separation of iron in a solution with high concentrations of potassium and sodium ions is achieved, which is of great significance for the treatment of iron-containing solution and wastewater in the chemical industry and metallurgy fields.

Evaluation of bi-directional causal association between periodontitis and benign prostatic hyperplasia: epidemiological studies and two-sample mendelian randomization analysis.

Background: Periodontitis and benign prostatic hyperplasia (BPH) are all common chronic diseases with higher incidence in middle-aged and old men. Several studies have indicated a potential association between periodontitis and BPH, although the findings remain inconclusive. However, there is no mendelian randomization (MR) studies to assess this association. Methods: The 40 men who had received health check-ups were included in an epidemiological study. Genetic data of BPH (13118 cases and 72799 controls) and periodontitis (3046 cases and 195395 controls) from FinnGen project was used to perform two-sample MR analysis. The inverse-variance weighted (IVW) model was identified as the primary analytical method, with MR Egger, weighted median, simple mode, and weighted mode serving as additional approaches. Results: The epidemiological analysis demonstrated a lack of statistically significant differences in the prevalence of clinical BPH between severe periodontitis group and non-severe periodontitis group. Similarly, no statistically significant differences were found in the prevalence of severe periodontitis among individuals with clinical BPH compared to those without. Additionally, Among the five models utilized in MR analysis, including the IVW model, no evidence of a causal link between periodontitis and BPH was observed. Conclusion: The findings from our epidemiological investigation and MR analysis do not provide support for a causal relationship between periodontitis and BPH.

Functionalized PLGA Microsphere Loaded with Fusion Peptide for Therapy of Bone Defects.

The challenges in the treatment of extensive bone defects are infection control and bone regeneration. Bone tissue engineering is currently one of the most promising strategies. In this study, a short biopeptide with specific osteogenic ability is designed by fusion peptide technology and encapsulated with chitosan-modified poly(lactic acid-glycolic acid) (PLGA) microspheres. The fusion peptide (FP) mainly consists of an osteogenic functional sequence (P-15) and a bone-specific binding sequence (Asp-6), which can regulate bone formation accurately and efficiently. Chitosan-modified PLGA with antimicrobial and pro-healing effects is used to achieve the sustained release of fusion peptides. In the early stage, the antimicrobial and soft tissue healing effects can stop the wound infection as soon as possible, which is relevant for the subsequent bone regeneration process. Our data show that CS-PLGA@FP microspheres have antibacterial and pro-cell migration effects in vitro and excellent pro-wound-healing effects in vivo. In addition, CS-PLGA@FP microspheres promote the expression of osteogenic-related factors and show excellent bone regeneration in a rat defect model. Therefore, CS-PLGA@FP microspheres are an efficient biomaterial that can accelerate the recovery of bone defects.

Histatin 1-modified SIS hydrogels enhance the sealing of peri-implant mucosa to prevent peri-implantitis.

Dental implants make it possible to replace teeth in more sophisticated ways. Nevertheless, peri-implantitis is one of the leading causes of implant failure, which can be avoided with proper soft tissue sealing. The aim of this study was to achieve the promotion of the synthesis of peri-implant epithelial hemidesmosome through Histatin 1 and porcine small intestinal submucosa (SIS) hydrogel to form a good peri-implant seal. The results show that hydrogel can improve the biological barrier function around implants by combining antibacterial, promoting soft tissue healing and promoting epithelial bonding. This means that the morphology and anti-infection ability of soft tissue are enhanced, which ensures the long-term stability of the implant.SIS-Hst1 hydrogel has certain clinical application in the prevention and early treatment of peri-implantitis. In conclusion, Hst1-SIS hydrogel, as a local administration system, provides experimental evidence for the prevention of peri-implant disease.

A Bone Targeting Nanoparticle Loaded OGP to Restore Bone Homeostasis for Osteoporosis Therapy.

Restoring bone homeostasis is the key to the treatment of osteoporosis. How to increase osteogenic ability or inhibit osteoclast activity has always been a topic of great concern. In recent years, short peptides with biological activity have received great attention in bone repair. However, the application of short peptides is still limited due to the lack of a stable and targeted delivery system. Poly(lactic-co-glycolic acid) (PLGA) nanoparticles modified by alendronate (AL) to transport osteogenic peptides (OGP) (AL-PLGA@P NPs) are designed. Benefiting from the high affinity of AL for hydroxyapatite, AL-PLGA@P NPs have the ability to target bone. In this delivery system, OGP that promotes osteogenesis synergizes with AL, which inhibits osteoclasts, to regulate bone homeostasis, which gives them more advantages in the treatment of osteoporosis. The data shows that nanoparticles can selectively deliver peptides to the bone surface without systemic toxicity. Moreover, nanoparticles can upregulate osteogenesis-related factors (ALP, Runx-2, and BMP2) and downregulate osteoclast-related factors (TRAP and CTSK) in vitro. With AL-PLGA@P NPs, bone microarchitecture and bone mass are improved in ovariectomized osteoporosis rats. Therefore, this study proposes a novel osteoporosis-based drug system that effectively improves bone density.

SIS membrane modification to improve antimicrobial and osteogenic properties for guide bone regeneration.

The guided bone regeneration (GBR) technique is the most common and durable approach to repairing bone defects in periodontal surgery. However, membrane exposure causes bacterial infiltration, which lowers the functional integrity of the barrier membrane and destroys bone repair. Here, an antibacterial peptide-modified small intestinal submucosa (SIS) membrane is used as a new GBR membrane for effective bone regeneration. The peptide JH8194 was placed into chitosan microspheres to preserve its stability and allow for sustained release, which realizes rapid and efficient functional modification of the SIS membrane. Biocompatibility and certain antibacterial activities were found in the modified SIS membrane (SIS@CS-JH8194). Additionally, in vitro experiments showed that SIS@CS-JH8194 promoted the expression of osteogenic-related factors and decreased the secretion of inflammatory factors in rat bone mesenchymal stem cells. In vivo experiments showed that SIS@CS-JH8194 could effectively promote bone regeneration in rat skull defects. In this work, we created a new antibacterial GBR membrane to help avoid postoperative infection and improve bone tissue regeneration.

An injectable multifunctional thermo-sensitive chitosan-based hydrogel for periodontitis therapy.

Bacteria are recognized as the driving factors of periodontitis. However, excessive reactive oxygen species (ROS) can harm periodontal tissue while also causing an uncontrolled inflammatory response. Hence, eliminating excessive ROS and blocking ROS-induced abnormal inflammatory response by antioxidants are achieving remarkable results in periodontitis therapy. Moreover, influenced by the deep and irregular periodontal pockets, injectable thermo-sensitive chitosan-based hydrogels have attracted a lot of attention. This study aimed to formulate an antibacterial and antioxidant therapeutic regimen by incorporating antimicrobial peptides (Nal-P-113) and/or antioxidants (polydopamine nanoparticles, PDNPs) into chitosan-based hydrogels. The hydrogel was characterized in vitro and finally examined in rats using the experimental periodontitis model. The release kinetics showed that the hydrogel could stably release Nal-P-113 and PDNPs for up to 13 days. The scavenging activity of the hydrogel against DPPH was about 80 % and the antibacterial ratio against Streptococcus gordonii (S. gordonii), Fusobacterium nucleatum (F. nucleatum) and Porphyromonas gingivalis (P. gingivalis) was about 99 %. Importantly, it was examined that the hydrogel had the ability to prevent periodontal tissue damage. Thus, chitosan-based hydrogels may provide a basis for designing multifunctional local drug delivery biomaterials for the treatment of periodontitis.

Selective separation of zinc and iron/carbon from blast furnace dust via a hydrometallurgical cooperative leaching method.

Blast furnace dust (BFD) contains ferrous and nonferrous metals and carbon, and is usually categorized as a typical secondary resource and hazardous waste produced by the iron-making process. The thermodynamic calculation and experimental investigation of the selective separation of zinc and iron/carbon from BFD via a NaCl-HCl-H2O system were carried out. Quantitative zinc and iron/carbon separation and recovery was achieved via a zinc-chloride (ZnCli2-i (i = 0, 1, 2, 3, 4)) cooperative leaching methodology using 3 mol/L NaCl at pH of 4, an L/S ratio of 4:1, a leaching temperature of 70 °C, a HCl concentration of 0.25 mol/L, and a leaching time of 2 h. Moreover, the total Cl- concentration used in for leaching was 2.09 mol (as concluded by the dosages of HCl and NaCl, and material). Results demonstrate that zinc was effectively leached from BFD, while the leaching of iron was hindered, in the acidic region. 93.2% of the zinc was extracted into a leaching solution containing 19.8 g/L zinc under the optimal conditions, and the ratio of the leaching agent to BFD was 300 mL to 75 g. The XRD and SEM-EDS analysis results of the residue reveal that ZnO and ZnS were leached, and the zinc-iron spinel (ZnFe2O4) was not leached and was present together with the iron oxide in the leaching residue. Iron and carbon in the leaching residue was enriched from 49.4% to 60.38%, and the iron and carbon were recovered as secondary resources that can be reused in the iron-making system.

Exploring soil erosion trajectories and their divergent responses to driving factors: a model-based contrasting study in highly eroded mountain areas.

Soil erosion threatens environmental sustainability worldwide. Exploring the trajectories of soil erosion and associated drivers is of great significance for combating land degradation. This study selected the highly eroded Loess Plateau (LP) and Karst Plateau (KP) as contrasting regions to monitor soil erosion dynamics. Monitoring was performed by applying the Revised Universal Soil Loss Equation based on a GIS platform and multi-source input data to investigate associated drivers. The results established that soil erosion in both regions was substantially reduced by ecological restoration projects and significant land use/cover conversions. Landscape and geomorphological variables were found to be the dominant factors controlling soil erosion in the LP and KP, as they influenced land use patches and geomorphological patterns, respectively. The correlations between fragmentation metric indices and soil erosion indicated that the appropriately intensive fragmentation in the LP could mitigate or prevent soil erosion by disturbing its formation and transportation and ultimately positively influenced soil erosion control. Geomorphological patterns were also determinative factors, particularly for the KP, where almost all geomorphological variables were significantly correlated with the erosion modulus. Owing to the peculiar landform and landscape conditions in karst areas and loess hilly-gully areas, geomorphological and landscape variables should be considered when determining the main factors affecting soil erosion processes and integrated into the forecasting model to improve the accuracy of the simulation. The findings of this study are expected to (i) improve the efficacy of soil erosion control and (ii) promote the sustainable planning and management of land and soil resources.

Acupoint catgut embedding for insomnia: Protocol for a systematic review and data mining.

BACKGROUND: Insomnia is a common sleep disorder characterized by chronically disturbed sleep or loss of sleep, and even cognitive dysfunction. Acupoint catgut embedding is widely used to treat sleep disorders. However, there is no systematic review and data mining of the effectiveness and potential acupoints prescription of acupoint catgut embedding for insomnia. METHODS: Randomized controlled trials (RCTs) from the Web of Science, PubMed, Cochrane Library, Springer, Wanfang database, China National Knowledge Infrastructure, VIP Chinese Science and Technology Journals Database, and 2 clinical trial registration center will be included. The search time will be established from each database to December 30, 2019. The outcome measures will be Pittsburgh sleep quality index (PSQI), clinical effective rate, International Unified Sleep Efficiency Value (IUSEV) and adverse events. Data from RCTs that meets the inclusion criteria will be analyzed through RevMan V.5.3 software. Risk of bias and publication bias will be analyzed to identify the quality of the included studies. Besides, Traditional Chinese Medicine inheritance support system (TCMISS) will be used to analyze the potential acupoints prescriptions. RESULTS: This study will clarify PSQI, IUSEV, clinical effective rate, adverse events, and potential acupoint prescriptions of acupoint catgut embedding for patients with insomnia. CONCLUSION: Our study will provide evidence of acupoint catgut embedding for insomnia, which may be beneficial to practitioners in the field of non-pharmacological interventions.PROSPERO registration number: CRD42019144636.

Induced fluorescent enhancement of protein-directed synthesized gold nanoclusters for selective and sensitive detection of flame retardants.

Organophosphate flame retardants (OPFRs), typical toxic and hazardous pollutants, are called for new detection approaches to avoid laborious synthetic procedures and large and expensive instruments. Hence, a novel fluorescent probe was constructed for quantitative detection of OPFRs via heightening the fluorescence of acetylcholinesterase synthesized gold nanoclusters (AChE-AuNCs). The as-prepared AChE-AuNCs exhibited high fluorescence emission at about 398 nm with the average particle size of about 1.60 nm. When the AChE-AuNCs was applied to the proposed fluorescent detection, excellent sensitivity with wide linear range (50-1000 ng L-1) and low detection limit (30 ng L-1) for TClPP with the response time less than 1 h were achieved. The fluorescent probe could be extended to detect other three types of OPFRs (TEP, TPHP, and TBOEP) and the target pollutants could be detectable in the presence of halogenated flame retardants. The mechanism might be mainly contributed by the interaction between OPFRs and AChE-AuNCs restricting internal vibration consumption of their capping ligands. The proposed detection approach could be easily operated and was not involved with other intermediate products. Therefore, AChE-AuNCs could be a promising fluorescent probe for rapid, selective and sensitive detection of OPFRs and even in the practical application.

Molecularly imprinted polymers on a silica surface for the adsorption of tobacco-specific nitrosamines in mainstream cigarette smoke.

Tobacco-specific nitrosamines are one of the most important groups of carcinogens in tobacco products. Using adsorbents as filter additives is an effective way to reduce tobacco-specific nitrosamines in cigarette smoke. Molecularly imprinted polymers (MIPs) using nicotinamide as template were grafted on the silica gel surface to obtain MIP@SiO2 and employed as filter additives to absorb tobacco-specific nitrosamines in mainstream cigarette smoke. Four milligrams of MIP@SiO2 per cigarette was added to the interface between filter and tobacco rod to prepare a binary filter system. The mainstream smoke was collected on an industry-standard Cambridge filter pad and extracted with ammonium acetate aqueous solution before analysis. Compared to the cigarette smoke of the control group, the levels of tobacco-specific nitrosamines with silica gel and with MIP@SiO2 were both reduced, and the adsorption rates of N-nitrosonornicotine, N-nitrosoanabasine, N-nitrosoanatabine, and 4-(methylnitrosamino)-1-(3-pyridine)-1-butanone with silica gel and with MIP@SiO2 were 20.76, 15.32, 18.79, and 18.01%, and 41.33, 34.04, 37.86, and 35.53%, respectively. Furthermore the content of total particle materials in cigarette smoke with silica gel was decreased evidently but showed no observable change with MIP@SiO2 . It indicated MIP@SiO2 could selectively reduce tobacco-specific nitrosamines in the mainstream cigarette smoke with no change to the cigarette flavor.

Recovery of H2SO4 from an acid leach solution by diffusion dialysis.

Diffusion dialysis with a series of anion exchange membranes was used to recover H(2)SO(4) from an acid leach solution produced during the vanadium manufacturing process. The effects of sulfuric acid, FeSO(4) and VOSO(4) concentration, flow rate and flow rate ratio on the recovery of H(2)SO(4) were investigated. The results showed that sulfuric acid permeated well through the membranes used, while metal ions were efficiently rejected. The recovery of H(2)SO(4) increased as the sulfate concentration of the feed increased and the flow rate ratio of water to feed increased. More than 80% of the H(2)SO(4) could be recovered from the leach solution which contained 61.7 g/L free H(2)SO(4), 11.2 g/L Fe and 4.60 g/L V at a flow rate of 0.19x10(-3) m(3)/h m(2). V and Fe ion rejection were within 93-95 and 92-94%, respectively. A preliminary economic evaluation revealed that an investment in this process could be recovered within 27 months.