Synthesis and fabrication of magnetically separable phosphate-modified magnetic chitosan composites for lead(II) selective removal from wastewater.

To address the urgent need for efficient removal of lead-containing wastewater and reduce the risk of toxicity associated with heavy-metal wastewater contamination, materials with high removal rates and easy separation must be developed. Herein, a novel organic-inorganic hybrid material based on phosphorylated magnetic chitosan (MSCP) was synthesized and applied for the selective removal of lead (II) from wastewater. From the characterization and the experimental results can be obtained that the magnetic saturation strength of MSCP reaches 14.65 emu/g, which can be separated quickly and regenerated readily, and maintains high adsorption performance even after 5 cycles, indicating that the adsorbent possesses good magnetic separation performance and durability. Also, MSCP showed high selective adsorption performance for lead in the multiple metal ions coexistence solutions at pH 6.0 and room temperature, with an adsorption coefficient SPb-MSCP of 78.85%, which was much higher than that of MSC (the SPb-MSC was 11.59%). Additionally, in the single lead system, the sorption characteristics of Pb(II) on MSCP and MCP had obvious pH-responsiveness, and their adsorption capacity increased with the increase of solution pH, reaching the maximal values of 80.19 and 72.68 mg/g, respectively. It is noteworthy that the acid resistance of MSCP with an inert layer coated on the core is significantly improved, with almost no iron leaching from MSCP over the entire acidity range, while MCP has 7.63 mg/g of iron leaching at pH 1.0. Significantly, MSCP exhibited a maximum adsorption capacity of 102.04 mg/g, which matches the Langmuir model at pH 6.0 and 298.15 K, and points to the pseudo-second-order kinetics of the chemisorption process of Pb(II) on MSCP. These findings highlight the great potential of MSCP for Pb(II) removal from aqueous solution, making it a promising solution for Pb(II) contamination in wastewater.

Research and experimental verification of lightweight loader rims.

The safety performance and structural stiffness of a rim, which is the main load-bearing structure of the loader during operation, influence the overall performance, stability, and braking capabilities of the machine. In the industry, researchers are currently pursuing lightweight and high-strength rims as a primary objective. A low weight not only enhances machinery fuel efficiency but also aligns with societal demands for sustainable development, energy conservation, and emission reduction. In this article, multiobjective optimization analysis on rims composed of three different materials is performed, and the relationships between various optimization parameters and target parameters are established using the results of response surface construction. Multiobjective genetic algorithms are utilized to derive various optimization plans, which are subsequently evaluated through static analysis, fatigue analysis, and weight loss analysis. The final optimization plan is determined based on the calculation results while considering production costs. Field tests are conducted on the optimized rims under various working conditions to verify the test results, evaluate the reliability of the finite element analysis results, and confirm the safety of the optimized rim.

Morphological measurements and classification of the navicular bone: a study based on computed tomography imaging.

OBJECTIVE: The purpose of this study was to present the classification of navicular bones and the anatomical basis for the diagnosis and treatment of navicular fractures of the foot. METHOD: 351 computed tomographic (CT) images of the navicular bone were analyzed and classified. The navicular bone's anatomical morphology was measured by three independent researchers in each type. Analysis and recording of the measurement results followed. RESULT: Navicular bones were assorted into three types: I shape(37.04%), II shape(54.41%), and III shape(8.55%). The left and right sides did not differ in any appreciable ways, except ab, bc, and ∠abc (P < 0.05); And all data were statistically different between men and women except for ∠abc (p > 0.05). CONCLUSION: The classification of the navicular bone in this study may be helpful in making the treatment decision for navicular fracture. LEVEL OF CLINICAL EVIDENCE: 4.

Effect analysis of medial bracing plate combined with cannulated screw in unstable femoral neck fracture assisted by surgical hip dislocation: a retrospective study.

BACKGROUND: Unstable femoral neck fractures have a high likelihood of causing severe disruption to the blood supply. This study aimed to assess the therapeutic effect of surgical hip dislocation using a medial support plate combined with cannulated screw fixation for the treatment of unstable femoral neck fractures in young and middle-aged adults. METHODS: We retrospectively analyzed the medical records of 68 young adults who underwent internal fixation of unstable femoral neck fractures. The observation group included 32 patients who had received medial support plate and cannulated screw fixation by the surgical hip dislocation method and 36 patients who had undergone anti-rotation screw composite compression system fixation comprised the comparison group. The amount of intraoperative bleeding, surgery duration, fracture recovery time and complications were recorded. The degree of femoral neck shortening and Garden index were assessed using the Zlowodzki method. Additionally, hip functionality was evaluated using the Harris score at 3 and 6 months and at the last follow-up. RESULTS: All 68 patients in both groups were followed up for 12-42 months (mean, 22.4 months). The postoperative incision was well-aligned and no inflation was observed. The intraoperative blood loss and surgery duration in the comparison group were longer than those in the observation. Additionally, the observation group had a significantly shorter fracture recovery time and a higher Garden index than the comparison at 6 months postoperatively; however, there was no significant statistical discrepancy between the two groups at the remaining time points. The observation group had higher Harris scores than the comparison at 3 and 6 months postoperatively. CONCLUSION: Surgical hip dislocation applied to the medial support plate combined with cannulated screw fixation has clinical application value in restoring the stability of femoral neck fractures while facilitating the maintenance of blood flow to the femoral head and neck.

Electronic Structure Optimization and Proton-Transfer Enhancement on Titanium Oxide-Supported Copper Nanoparticles for Enhanced Nitrogen Recycling from Nitrate-Contaminated Water.

Electrocatalytic reduction of nitrate to NH3 (NO3RR) on Cu offers sustainable NH3 production and nitrogen recycling from nitrate-contaminated water. However, Cu affords limited NO3RR activity owing to its unfavorable electronic state and the slow proton transfer on its surface, especially in neutral/alkaline media. Furthermore, although a synchronous "NO3RR and NH3 collection" system has been developed for nitrogen recycling from nitrate-laden water, no system is designed for natural water that generally contains low-concentration nitrate. Herein, we demonstrate that depositing Cu nanoparticles on a TiO2 support enables the formation of electron-deficient Cuδ+ species (0 < δ ≤ 2), which are more active than Cu0 in NO3RR. Furthermore, TiO2-Cu coupling induces local electric-field enhancement that intensifies water adsorption/dissociation at the interface, accelerating proton transfer for NO3RR on Cu. With the dual enhancements, TiO2-Cu delivers an NH3-N selectivity of 90.5%, mass activity of 41.4 mg-N h gCu-1, specific activity of 377.8 mg-N h-1 m-2, and minimal Cu leaching (<25.4 µg L-1) when treating 22.5 mg L-1 of NO3--N at -0.40 V, outperforming most of the reported Cu-based catalysts. A sequential NO3RR and NH3 collection system based on TiO2-Cu was then proposed, which could recycle nitrogen from nitrate-contaminated water under a wide concentration window of 22.5-112.5 mg L-1 at a rate of 209-630 mgN m-2 h-1. We also demonstrated this system could collect 83.9% of nitrogen from NO3--N (19.3 mg L-1) in natural lake water.

Electrocatalytic hydrodechlorination system with antiscaling and anti-chlorine poisoning features for salt-laden wastewater treatment.

The high salinity and coexistence of scaling ions (Ca2+, Mg2+, HCO3-) in wastewater challenge the efficacy and durability of palladium (Pd)-mediated electrocatalytic hydrodechlorination (EHDC) reaction for chlorinated organic pollutant detoxification, due to the accompanying Cl- poisoning at Pd sites and scaling on electrode. In a concentrated NaCl solution (5.8 g L - 1) with Ca2+ (80.0 mg L - 1), Mg2+ (30.0 mg L - 1) and HCO3- (180.0 mg L - 1), the EHDC efficiency of Pd towards 2,4-dichlorophenol decreases significantly from 67.8% to 33.1% in 72.0 h of reaction, and the electrode is covered with layers of fluffy aragonite precipitate. Herein we demonstrate the inclusion of a commercial antiscalant 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTC) can prevent both scale formation and Cl- poisoning, leading to an efficient and steady EHDC process. A mechanistic study reveals that the unique dual function of PBTC primarily originates from the bearing phosphonate and carboxyl groups. With the large affinity of these groups (especially the phosphonate group) for scaling cations and Pd, the PBTC can chelate and stabilize the scaling cations in water and replace Cl- at Pd surface. It can also release protons, and trigger the formation of more electron-deficient Pdδ+ species via PBTC-Pd binding, leading to an enhanced EHDC. This work provides effective solutions to the scaling/poisoning issues that commonly encountered in real wastewater and paves a solid road for EHDC application in pollution abatement.

Sedimentary phosphorus fractions in typical lacustrine wetland of Changshou Lake flowing into the Three-Gorges Reservoir.

River damming is ubiquitous which would impact the nutrient cycles of the river systems. Here an early eutrophicated reservoir (Changshou Lake) of the Three Gorges Reservoir (TGR) was selected to investigate the phosphorus (P) biogeochemical migration. Nine sediment cores were collected in the littoral nature lacustrine wetland to help to determine the phosphorus distribution and fraction along the water level. Results revealed that the concentrations of phosphorus varied from 106 to 1178 mg/kg, with the highest concentration reported in the shallow water area. This was affected by the fluctuations of the water level and algae accumulation from the deep-water. In addition, it also indicated that the higher accumulation of phosphorus in the shallow water areas was predominated by HCl-P and BD-P fractions, which were potentially the main source of phosphorus in lacustrine wetlands. Hence, more attention should be paid to the autochthonous phosphorus control in the water level fluctuation area.

The efficacy and safety of sulindac for colorectal polyps: A protocol for systematic review and meta-analysis.

BACKGROUND: Sulindac has been used for treating colorectal polyps widely. However, the efficacy and safety of sulindac for colorectal polyps are unclear. This study aims to evaluate the efficacy and safety of sulindac for colorectal polyps. METHODS: Randomized controlled trials of sulindac in the treatment of colorectal polyps will be searched in PubMed, EMbase, Cochrane Library, Web of Science, China National Knowledge Infrastructure (CNKI), WanFang, the Chongqing VIP Chinese Science, and Technology Periodical Database, and China biomedical literature database (CBM) from inception to August, 2020. And Baidu Scholar, Google Scholar, International Clinical Trials Registry Platform, and Chinese Clinical Trials Registry will be searched to obtain more relevant studies comprehensively. Two researchers will perform data extraction and risk of bias assessment independently. Statistical analysis will be conducted in RevMan 5.3. RESULTS: This study will summarize the present evidence by exploring the efficacy and safety of sulindac in the treatment of colorectal polyps. CONCLUSION: The findings of the study will provide helpful evidence for the efficacy and safety of sulindac in the treatment of colorectal polyps, facilitating clinical practice and further scientific studies. ETHICS AND DISSEMINATION: The private information from individuals will not publish. This systematic review also will not involve endangering participant rights. Ethical approval is not required. The results may be published in a peer-reviewed journal or disseminated in relevant conferences. OSF REGISTRATION NUMBER: DOI 10.17605/OSF.IO/N5GDH.

Characterization of the complete mitochondrial genome of the firefly, Luciola substriata (Coleoptera: Lampyridae).

The firefly, Luciola substriata (Coleoptera: Lampyridae), is an aquatic firefly species, whose larvae inhabit ponds or lakes. Here we present the complete mitochondrial (mt) genome of the firefly (GenBank accession number KP313820) and provide its annotation. This circular genome is 16,248 bp in length and contains 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes, and a non-coding AT-rich region. Similar to other firefly species, the base composition of this mitochondrial genome is also biased toward A and T (44.09% A, 34.00% T, 12.89% C, and 9.01% G). All 13 protein-coding genes start with a typical mitochondrial start codon, and terminate with a usual stop codon TAA, or TAG or a single T. The non-coding AT-rich region (1636 bp in length) include one (A)20, and two (T)15 tandem repeats, and one (AAT)5 element. This mitochondrial genome sequence will promote a better understanding for firefly evolution in the future.

An ignored variable: solution preparation temperature in protein crystallization.

Protein crystallization is affected by many parameters, among which certain parameters have not been well controlled. The temperature at which the protein and precipitant solutions are mixed (i.e., the ambient temperature during mixing) is such a parameter that is typically not well controlled and is often ignored. In this paper, we show that this temperature can influence protein crystallization. The experimental results showed that both higher and lower mixing temperatures can enhance the success of crystallization, which follows a parabolic curve with an increasing ambient temperature. This work illustrates that the crystallization solution preparation temperature is also an important parameter for protein crystallization. Uncontrolled or poorly controlled room temperature may yield poor reproducibility in protein crystallization.

Application of fish index of biological integrity (FIBI) in the Sanmenxia Wetland with water quality implications.

Long-term changes of fish biotic integrity in the Sanmenxia Wetland, North China, since the 1950s were assessed using the fish index of biological integrity (FIBI). The water and sediment quality was evaluated by the water quality index (WQI) and sediment pollution index (SPI). The results showed that FIBI continuously decreased from 46 to 20 during the past 5 decades, which indicated that the fish community state shifted from fair to very poor conditions, and damming by itself did not affect the fish biotic integrity. At the same time, WQI fell from 83 to 44.1, and SPI increased from 0.99 to 2.14 since the 1960s, resulting from fast regional socio-economic development and insufficient wastewater treatment. Correlation analysis suggested that water quality significantly affected biotic integrity (r=0.867, p<0.05) through direct effects on the fish community. As a representative example of many wetlands in North China, our study clearly demonstrated that the biological integrity was degraded, induced both by water quality deterioration and sediment pollution, further driven by the contradiction between rapid development of regional economy and lagging development of sewage treatment facilities, which were thought to be the main factor responsible for the degradation of biological integrity.

[Sediment risk assessment and heavy metal source analysis in typical country water level fluctuated zone (WLFZ) of the Three Gorges].

Typical country WLFZ in Zhongxian located in the core region of the Three Gorges Reservoir was chosen as research subject in this study. In July 2012, sediment samples of WLFZ were collected after dam water level dropped. Heavy metals were analyzed for sediment potential risk assessment and then applied for sources analysis in this area, which supplied basic data for non-point pollutants control. The results showed that As, Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn ranged in 155-160 m:5.17-14.81, 0.06-0.57, 8.55-20.56, 62.79-93.04, 15.38-60.97, 425.72-782.32, 21.34-48.5, 23.03-43.39 and 57.78-130.10 mg x kg(-1), and 170-175 m: 7.05-12.57, 0.17-0.33, 10.71-18.89, 65.22-92.89, 18.89-42.91, 74.06-774.41, 22.47-42.49, 24.17-29.23, 55.67-103.18 mg x kg(-1), respectively. Index of geo-accumulation (Igeo) suggested the accumulation orders were Cd > Co > Mn > As > Cu > Pb > Zn in 155-160m WLFZ and Co > Mn > Cd > As in 170-175 m WLFZ. Sediment pollution index (SPI) showed that sediments in 155-160 m WLFZ had higher potential risk than that of 170-175 m with the highest risk appeared in 155-166 m WLFZ site located downstream of Zhongxian. In 155-160 m WLFZ, Cr, Cu, Pb and Zn were mainly originated from natural resources, while As, Ni, Cd, Co and Mn were possibly sourced from upland water. In contrast, in 170-175 m WLFZ, Cr, Ni, Pb and Zn in the sediment came from natural resources, while Cd, As, Co, Mn and Cu were probably rooted from both agricultural non-point source and upland water.

[Heavy metals distribution and risk assessment of sediments in the riverine wetland of Sanmenxia Reservoir].

The survey for contents and fractions of heavy metal in sediments of riverine wetland in Sanmenxia Reservoir were carried out. Sediment pollution index was applied to assess the potential ecological risk and mass fraction of heavy metal in surface sediment was conducted for release risk assessment. The results showed that the total concentrations of Cr, Ni, Cu, Zn, Cd and Pb ranged in 25.8-68.5, 12.1-36.7, 3.25-48.74, 33.5-472.4, 0.16-0.69 and 9.04-90.74 mg x kg(-1), respectively. The heavy metal contents in the sediments increased obviously from the upper reaches of reservoir to Sanmenxia dam. The concentrations of Ni, Cu, Zn, Cd, Pb in sediments were higher in lower reach located after Weihe River than those of the upstream. The Weihe River was the biggest branch of Yellow River, and heavy metals accumulated obviously in the sediments of typical polluted branch (Hongnongjian River) , which might be attributed to the long-term discharge of industrial wastewater. The sediment pollution index (SPI) of Sanmenxia Reservoir ranged from 1.83 to 7.39, with an average value for 3.11. Sediment pollution aggravated in the downstream after Weihe River flowed in, and SPI reached 6.33 in Hongnongjian River mouth for medium risk. The exchangeable and carbonates fraction of Cd, Cu and Pb mass fractions in surface sediments accounted for 63.8%-85.7%, 6.58%-22.62% and 10.6%-28.9%, respectively. The pollutants discharge in branches caused heavy metal accumulation, ecological risk aggravation in lower reach of Sanmenxia basin. And the release risk followed the sequence Cd > Pb > Cu > Ni in surface sediment. The conclusions of this article supplied reference and basis for sediment pollution treatment and in situ remediation.

Effectiveness of vegetation on phosphorus removal from reclaimed water by a subsurface flow wetland in a coastal area.

This work was conducted to evaluate the effectiveness and influence factors of vegetation on phosphorus (P) removal from reclaimed water in constructed wetlands. Comparisons were conducted between one pilot scale subsurface flow wetland (P-SSFW) and two demonstration subsurface flow wetlands, which were series-wound and named as first subsurface flow wetland (F-SSFW), and second subsurface flow wetland (S-SSFW), respectively. The three wetlands had the same vegetation and substrate, but different pH values, total dissolved solids (TDS) and P loads. Results showed that the P content in the vegetation shoots of the F-SSFW was 2.16 mg/g, while 2.31 mg/g in the S-SSFW and 2.69 mg/g in the P-SSFW. These differences were likely caused by the higher pH and TDS in the reclaimed water. The P content also differed among the tissues of the plant, which were 5.94-6.44 mg/g, 2.20-2.77 mg/g, 1.31-1.46 mg/g and 1.53-1.88 mg/g in the flowers, leaves, stems, and roots, respectively. The greatest discrepancy was observed in the leaves, indicating that the environment of the wetlands had the greatest influence on the leaves. When the total phosphorus (TP) load was lower, the proportion of P removed by vegetation assimilation was 16.17% in the P-SSFW, 12.90% in the F-SSFW and 13.29% in the S-SSFW. However, the relative removal efficiency by vegetation among the three wetlands did not vary greatly from that observed in other studies. Moreover, the influence of pH, TDS and TP load was not as great as the influence of the vegetation species, type of substrate, influent style or climate.

Morphological stable spirobifluorene/oxadiazole hybrids as bipolar host materials for efficient green and red electrophosphorescence.

A series of 9,9'-spirobifluorene/oxadiazole hybrids with various linkages between two components, namely SBF-p-OXD (1), SBF-m-OXD (2), and SBF-o-OXD (3) are designed and synthesized through Suzuki cross-coupling reactions. The incorporation of a rigid and bulky spirobifluorene moiety greatly improves their thermal and morphological stability, with T(d) (decomposition temperature) and T(g) (glass transition temperature) in the ranges of 401-480 degrees C and 136-210 degrees C, respectively. 2 and 3 with meta- and ortho-linkage display higher triplet energy and blue-shifted absorption and emission than their para-linked analogue 1 owing to the decreasing pi-conjugation between the two components. Their HOMO and LUMO energy levels depend on the linkage modes within the range of 5.57-5.64 eV and 2.33-2.49 eV, respectively. Multilayer deep red electrophosphorescent devices with 1-3 as hosts were fabricated and their EL efficiencies follow the order of 3 (o)>2 (m)>1 (p), which correlates with their triplet energy and the separation of HOMO and LUMO distributions at molecular orbitals. The maximum external quantum efficiencies of 11.7% for green and 9.8% for deep red phosphorescent organic light-emitting diodes (OLEDs) are achieved by using 2 and 3 as host materials, respectively.

Multifunctional bipolar triphenylamine/oxadiazole derivatives: highly efficient blue fluorescence, red phosphorescence host and two-color based white OLEDs.

Two simple triphenylamine/oxadiazole derivatives were synthesized and fully characterized; their multifunctionality as highly efficient non-doped blue fluorescence, excellent red phosphorescent host and single-doped two-color based white OLEDs has been demonstrated.

[Expression of estrogen receptor, progesterone receptor and integrin alphaVbeta3 in endometrium of patients with luteinized unruptured follicle.].

OBJECTIVE: To investigate endometrium receptivity in patients with luteinized unruptured follicle (LUF) by measuring the expression of estrogen receptor (ER), progesterone receptor (PR) and integrin alphaVbeta3 in the endometrium. METHODS: From May 2007 to Nov. 2007, 17 infertile women with LUF were selected as LUF group matched with 13 infertile cases with normal ovulation as control group. They all underwent frozen-thawed embryo transfer in Reproductive Medicine Center, Renmin Hospital of Wuhan University. Endometrial tissue in anterior and posterior wall of uterus of LUF group and control group were biopsied by a small curettage between 7 and 11 days after luteinizing hormone (LH) surge. The expression of ER, PR and integrin alphaVbeta3 in endometrium were detected by immunohistochemistry staining. The level of estrogen and progesterone were measured by chemiluminescence assay. Then, the relationship between alphaVbeta3 expression in endometrium and the level of estrogen/progesterone were analyzed in LUF patients. RESULTS: (1) There was no remarkable difference in the level of estrogen between LUF [(656 +/- 299) pmol/L] and control group [(727 +/- 275) pmol/L, P > 0.05]. However, the level of progesterone were (23 +/- 8) nmol/L in LUF group and (35 +/- 10) nmol/L in control group, which reached statistical difference (P < 0.01). (2) The expression of ER, PR in endometrium of LUF patients were 183.9 +/- 2.4 and 168 +/- 3, which were significantly higher than 109.4 +/- 6.3 and 106 +/- 4 in control group (P < 0.01). The expression of integrin alphaVbeta3 in endometrium of 115 +/- 11 in LUF group were significantly lower than 191 +/- 9 in control group (P < 0.01). (4) In LUF group, the expression of alphaVbeta3 in endometrium was correlated positively with the level of progesterone (r = 0.77, P < 0.01) and irrelevant with the level of estrogen (r = 0.01, P > 0.05). CONCLUSION: The higher expression of estrogen and progesterone and lower expression of integrin alphaVbeta3 might confer impaired receptivity of endometrium and interfere with embryo implantation.