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In this paper, the vibration of a thin plate system with piezoelectric sheets attached and its acoustic radiation are modeled theoretically. Then the results are compared with those of finite element simulation, and the results are relatively consistent. Finally, sound absorption and isolation experiments at non-intrinsic frequencies of the composite plate are conducted in a standing wave tube. Based on the principle of minimum potential energy, the variation equation of a thin plate with a piezoelectric sheet attached are listed, and the impedance matrix of the acoustic radiation of the plate coupled with each order of the cavity modal is calculated. After the modal displacement response of the plate is obtained, the absorption coefficient and sound insulation volume of the composite plate can be calculated. Through theoretical calculations and finite element simulations, it is found that the plate has a modal reorganization phenomenon at the peak of sound insulation, and the modal response of each order increases at the peak of sound absorption. After that, the sound absorption and isolation experiments were conducted in the standing wave tube, and the control effect of the piezoelectric shunt oscillator at the non-intrinsic frequency of the plate was improved by adding negative capacitance.

Neural regeneration has troubled investigators worldwide in the past decades. Currently, cell transplantation emerged as a breakthrough targeted therapy for spinal cord injury (SCI) in the neurotrauma field, which provides a promising strategy in neural regeneration. Olfactory ensheathing cells (OECs), a specialized type of glial cells, is considered as the excellent candidate due to its unique variable and intrinsic regeneration-supportive properties. In fact, OECs could support olfactory receptor neuron turnover and axonal extension, which is essential to maintain the function of olfactory nervous system. Hitherto, an increasing number of literatures demonstrate that transplantation of OECs exerts vital roles in neural regeneration and functional recovery after neural injury, including central and peripheral nervous system. It is common knowledge that the deteriorating microenvironment (ischemia, hypoxia, scar, acute and chronic inflammation, etc.) resulting from injured nervous system is adverse for neural regeneration. Interestingly, recent studies indicated that OECs could promote neural repair through improvement of the disastrous microenvironments, especially to the overwhelmed inflammatory responses. Although OECs possess unusual advantages over other cells for neural repair, particularly in SCI, the mechanisms of OEC-mediated neural repair are still controversial with regard to anti-inflammation. Therefore, it is significant to summarize the anti-inflammation property of OECs, which is helpful to understand the biological characteristics of OECs and drive future studies. Here, we mainly focus on the anti-inflammatory role of OECs to make systematic review and discuss OEC-based therapy for CNS injury.

Objective: To investigate the independent influencing factors of bone cement displacement following percutaneous vertebral augmentation (PVA) in patients with stage I and stage II Kümmell’s disease. Methods: We retrospectively reviewed the records of 824 patients with stage Ⅰ and stage Ⅱ Kümmell’s disease treated with percutaneous vertebroplasty (PVP) or percutaneous vertebroplasty (PKP) from January 2016 to June 2022. Patients were divided into the postoperative bone cement displacement group (n = 150) and the bone cement non-displacement group (n = 674) according to the radiographic inspection results. The following data were collected: age, gender, body mass index (BMI), underlying disease, bone mineral density (BMD), involved vertebral segment, Kümmell’s disease staging, anterior height, local Cobb angle, the integrity of anterior vertebral cortex, the integrity of endplate in surgical vertebrae, surgical method, surgical approach, the volume of cement, distribution of cement, the viscosity of cement, cement leakage, and postoperative anti-osteoporosis treatment. Binary logistic regression analysis was performed to determine the independent influencing factors of bone cement displacement. The discrimination ability was evaluated using the area under the curve (AUC) of the receiver operating characteristic (ROC). Results: The results of logistic regression analysis revealed that thoracolumbar junction (odds ratio (OR) = 3.23, 95% confidence interval (CI) 2.12–4.50, p = 0.011), Kümmell’s disease staging (OR = 2.23, 95% CI 1.81–3.41, p < 0.001), anterior cortex defect (OR = 5.34, 95% CI 3.53–7.21, p < 0.001), vertebral endplates defect (OR = 0.54, 95% CI 0.35–0.71, p < 0.001), cement distribution (OR = 2.86, 95% CI 2.03–3.52, p = 0.002), cement leakage (OR = 4.59, 95% CI 3.85–5.72, p < 0.001), restoration of local Cobb angle (OR = 3.17, 95% CI 2.40–5.73, p = 0.024), and postoperative anti-osteoporosis treatment (OR = 0.48, 95% CI 0.18–0.72, p = 0.025) were independently associated with the bone cement displacement. The results of the ROC curve analysis showed that the AUC was 0.816 (95% CI 0.747–0.885), the sensitivity was 0.717, and the specificity was 0.793. Conclusion: Thoracolumbar fracture, stage Ⅱ Kümmell’s disease, anterior cortex defect, uneven cement distribution, cement leakage, and high restoration of the local Cobb angle were risk factors for cement displacement after PVA in Kümmell’s disease, while vertebral endplates defect and postoperative anti-osteoporosis treatment are protective factors.

Spinal cord injury (SCI) usually results in loss or reduction in motor and sensory functions. Despite extensive research, no available therapy can restore the lost functions after SCI. Reactive astrocytes play a pivotal role in SCI. Rho kinase inhibitors have also been shown to promote functional recovery of SCI. However, the role of Rho kinase inhibitors in reactive astrocytic phenotype switch within SCI remains largely unexplored. In this study, astrocytes were treated with proinflammatory cytokines and/or the Rho kinase inhibitor Y27632. Concomitantly the phenotype and morphology of astrocytes were examined. Meanwhile, the SCI model of SD rats was established, and nerve functions were evaluated following treatment with Y27632. Subsequently, the number of A1 astrocytes in the injured area was observed and analyzed. Eventually, the expression levels of nuclear factor kappa B (NF-κB), C3, and S100A10 were measured. The present study showed that the Rho kinase inhibitor Y27632 improved functional recovery of SCI and elevated the proliferation and migration abilities of the astrocytes. In addition, Y27632 treatment initiated the switch of astrocytes morphology from a flattened shape to a process-bearing shape and transformed the reactive astrocytes A1 phenotype to an A2 phenotype. More importantly, further investigation suggested that Y27632 was actively involved in promoting the functional recovery of SCI in rats by inhabiting the ROCK/NF-κB/C3 signaling pathway. Together, Rho kinase inhibitor Y27632 effectively promotes the functional recovery of SCI by shifting astrocyte phenotype and morphology. Furthermore, the pro-regeneration event is strongly associated with the ROCK/NF-κB/C3 signal pathway.

Introduction: Traumatic spinal cord injuries (TSCI) are worldwide public health problems. There has been a lack of extensive multi-center study of TSCI epidemiology in Northwest China in pre- and post-pandemic period of COVID-19. Materials and Methods: A multi-center retrospective study of 14 hospitals of Northwest China was conducted on patients with TSCI between 2017 and 2020. Variables assessed included patient demographics, etiology, segmental distribution, treatment, waiting time for treatment and outcomes.Results: The number of patients with TSCI showed an increasing trend from 2017 to 2019 while there were fewer patients in 2020 than in 2019. The male-to-female ratio was 3.67:1 and the mean age was 48±14.9. The major cause of TSCI was high fall (38.8%), low fall (27.7%), traffic accidents (23.9%), sports (2.6%) and others (7.0%). The segmental distribution showed a bimodal pattern, peak segments were C6 and Tl1, L1(14.7%) was the most frequently injured segments. Incomplete injury (72.8%) occurred more often than complete injury (27.2%). ASIA scale of most patients did not change before and after treatment both in operational or conservative group. 975 patients from urban and 1646 patients from rural areas were conducted, most urban residents could rush to get treatment after injured immediately (Conclusion: The incidence of TSCI in Northwest China is high and growing. However, under the pandemic policy reasons, it has decreased in 2020. The promotion of online work may be an effective primary prevention measures for trauma. Also, due to the distance from the hospitals with proper conditions, rural patients need to spend long time to there, the timely treatment of them should be paid attention.

To observe the efficacy of intravenous, topical, and combined application of tranexamic acid (TXA) in patients with thoracolumbar fracture fixed with percutaneous pedicle screw, and to identify the optimal application method of TXA.A total of 181 patients with thoracolumbar fracture treated with percutaneous pedicle screw fixation were enrolled in this randomized controlled trial and were randomly classified into 3 groups, including group A (intravenous group), group B (topical group), and group C (combined group). The total blood loss (TBL), hidden blood loss (HBL), intraoperative blood loss (IBL), preoperative D-dimer, postoperative D-dimer, incidence of deep vein thrombosis (DVT), and incidence of other complications were compared and analyzed among the 3 groups.TBL, HBL, and IBL in the topical group 24 hours after operation were higher (P0.05) than those in the intravenous group and combined group, whereas the difference between the intravenous group and combined group was not statistically significant. Meanwhile, there was no statistically significant difference in operation time, preoperative D-dimer, and postoperative D-dimer among the 3 groups (P0.05), but D-dimer in all groups at 72 hours after surgery was higher than that before surgery. No DVT or other complication was observed in the patients.Preoperative intravenous drip of TXA can remarkably reduce intraoperative HBL and IBL in patients with thoracolumbar fracture fixed with percutaneous pedicle screw. Nonetheless, intraoperative topical application of TXA before wound closure is not recommended.

Background: Fusion with a titanium mesh cage (TMC) has become popular as a conventional method after cervical anterior corpectomy, but postoperative TMC subsidence has often been reported in the literature. We designed a novel anatomic cervical TMC to reduce the postoperative subsidence rate. This finite element study aims to investigate the anti-subsidence performance of a novel anatomic TMC and provide a theoretical basis for clinical application. Methods: According to the test process specified in the ASTM F2267 standard, three-dimensional finite element analysis was used to compare the anti-subsidence characteristics of a traditional TMC (TTMC) and novel TMC (NTMC). Abaqus software was used for the mesh, and the modulus of elasticity, Poisson's ratio and other material coefficients of each part were input into the model. Solidworks software was used to establish the TTMC and NTMC models and construct the two three-dimensional finite element models of TMC subsidence testing mentioned above. Through analysis, the relationships between the stiffness of the intervertebral body fusion device (Kd) and the stiffness of the polyurethane foam blocks (Ks) of the TTMC and NTMC were derived, respectively. Results: After fitting the linear segment, the Kd values of the TTMC and NTMC were 37314 N/mm and 89124 N/mm, respectively. After calculation, the Ks values of the TTMC and NTMC were 653.83 N/mm and 995.95 N/mm, respectively. The Kp values of the TTMC and NTMC were calculated to be 665.5 N/mm and 1007.2 N/mm according to the formula. Conclusion: The reported novel anatomic titanium mesh cage (NTMC) significantly improved the anti-subsidence performance after ACCF, which was approximately 51.3% higher than that of the traditional titanium mesh cage.

In worldwide, osteoporosis has become one of the severe public health distress and over 200 million people get affected by tenderness and fissure during their life period. Vicenin-2 is a naturally occurring flavonoid glycoside present in Moringa oleifera, Peperomia blanda and Ocimum sanctum Linn with numerous biological activities. The present study aims to assess the effect of Vicenin-2 on ovariectomy-induced postmenopausal osteoporosis in female rats. Surgical removal of ovaries was achieved to institute the ovariectomy animal model. The ovariectomized (OVX) animals were alienated into four groups: Control, OVX alone (model), OVX with Vicenin-2 (5 mg/kg b.w), and OVX with Vicenin-2 (10 mg/kg b.w). Also, their consistent conduct remained managed intragastrically for about 12 weeks. OVX rats treated with Vicenin-2 effectually improved body mass, uterus index, lipid profiles, inflammatory markers, bone turnover markers and amplified the presence of calcium in the OVX rat serum. Vicenin-2 was found to suppress the actions of ACP, E2, and BGP in OVX rats. Besides, Vicenin-2 showed some adverse effects over histomorphometric percentage and histological studies, in which tabular thickness and area were restored in the control and Vicenin-2 managed OVX rats. PCR results of Alp, Runx 2, Osx showed diminished expressions in OVX rats whereas treatment with Vicenin-2 displays up-regulated expression of these genes. Through our study, we established that Vicenin-2 did not wield a detrimental upshot on the skeletal organization of OVX rats. Besides, we put forward that Vicenin-2 could be an excellent candidate to treat and manage bone related disease or disorders.

In thoracolumbar vertebral tumors, reconstruction of complex multi-segment thoracolumbar vertebrae after total en-bloc spondylectomy (TES) is still challenging. In recent years, with the development of 3D printing technology, individualized 3D printed artificial vertebrae have been attempted to reconstruct complex multi-segment thoracolumbar spine. Compared with traditional titanium mesh or bone transplantation, it helps reduce long-term complications, bringing a new dawn for reconstructing multi-segment thoracolumbar spine. A 69-year-old female complained of low back pain with limited motion for 1 month. More than 2 months ago, she underwent radical mastectomy due to breast cancer (Luminal A subtype). Imageology examination revealed an osteolytic lesion involving the T11-L1 vertebra. She was performed one-stage 3-segment (T11-L1) en-bloc spondylectomy via posterior approach, and then an artificial vertebrae produced by a novel individualized 3D printing technology was used for reconstruction. The patient was follow-up for 2 years, and she recovered well, with no tumor recurrence, and no complications after spinal reconstruction. The application of individualized 3D printed artificial vertebrae in multi-segment thoracolumbar spine reconstruction can not only reconstruct the bone defect more accurately through the individualized design, but the porous design is able to achieve biomechanical performance comparable to that of cancellous bone, and it is conducive to inducing bone growth, all of which help reduce long-term mechanical complications. Furthermore, the application of artificial vertebrae in surgery can significantly shorten the operation time, reduce intraoperative blood loss and reduce the risk of perioperative complications. Therefore, individualized 3D printed artificial vertebrae is a good choice for complex multi-segment thoracolumbar spine reconstruction.

With the development of radiology and minimally invasive technology, vertebroplasty has become the mainstream treatment for Kummell’s disease. However, the catastrophic complication of bone cement displacement appears occasionally. We use robot-assisted pediculoplasty combined with vertebroplasty to avoid such complications. From January 2015 to January 2018, 87 patients suffering from thoracolumbar Kummell’s disease without neurological symptoms were treated by robot-assisted pediculoplasty combined with vertebroplasty. Pediculoplasty as a “bridge” allows the bone cement at the anterior edge of the vertebral body to be fixed in the vertebral body through the intrapedicular cement, which can effectively prevent bone cement displacement. The clinical efficacy was evaluated based on the statistical analysis results of vertebral body index (VBI), Cobb angle, visual analogue scale (VAS), and Oswestry disability index (ODI) at 3, 6, 12, 18, and 24 months after treatment. The average operation time was 85.23±10.48 min, and the average volume of cement injected was 4.97±0.66 ml. The patients’ preoperative VBI, Cobb angle, VAS and ODI scores were 62.01±11.32, 33.78±11.99°, 7.47±0.82, and 78.37±7.14, respectively. The postoperative measurements were 87.06±4.45, 16.57±6.46°, 2.89±0.95, and 46.91±8.44. At the last follow-up, the outcomes were 86.82±4.27, 16.72±6.22°, 1.75±0.69, and 20.48±4.48, respectively. There was significant difference between the preoperative and postoperative data, as well as the preoperative and the last follow-up data (P

The excessive proliferation of filamentous green algae (FGA) has been considered to be one of the important factors that result in poor growth or even a decline in submerged macrophytes. This study aims to investigate why FGA has stronger growth advantage than that of submerged macrophytes in the co-culture system. Assimilation of nitrogen and phosphorus nutrients, kinetics, and interspecific nutrient competition model were studied to determine the dynamic changes in nutrient assimilation between submerged macrophytes and FGA in a co-culture system with ion depletion technique. The results showed that differences were observed in the assimilation of nitrogen and phosphorus by Vallisneria natans, Ceratophyllum demersum, and Cladophora oligoclona. C. oligoclona was able to assimilate and accumulate much more nitrogen than V. natans and C. demersum, with the content of nitrogen of 5.75% (dry mass). The lower value of Michaelis-Menten constant K m (0.34 mg/L) of C. demersum indicated that C. demersum had a greater affinity for phosphate. The interspecific competition results confirmed that the coexistence of V. natans and C. oligoclona, and C. demersum and C. oligoclona were unstable. Moreover, C. demersum had a stronger competitive ability than V. natans, and it can be used as a pioneer species for the recovery of submerged vegetation in eutrophic lakes.

Chiral plasmonic systems have been shown to exhibit stronger circular dichroism (CD) because of strong interaction between light and noble metals. In this study, we utilize double-layer chiral plasmonic nanostructures composed of achiral nanoplate and two achiral nanodisks to produce a chiroptical response. The chiroptical response is due to the twisted electric dipoles and the phase between them. In addition, the CD signal of the plasmonic nanostructure can be accurately regulated when plasmonic nanostructure parameters are tuned. Overall, results will allow further tuning of the optical responses in plasmonic systems to tailor chiral light–matter interaction.

We report the structure, magnetocaloric effect, and critical phase transition in the manganite La 2 Sm 0.4 Sr 0.6 Mn 2 O 7 (LSSMO) synthesized by a sol-gel method. X-ray diffraction together with Rietveld refinement show that the sample crystallizes in a Sr 3 Ti 2 O 7 -type tetragonal structure with a space group of I 4/ mmm . This compound undergoes a second-order ferromagnetic (FM) to paramagnetic phase transition at T C =348 K and shows strong FM properties below the T C . Based on the data of isothermal magnetization measured around the T C and Maxwell's relation, we calculated the maximum magnetic entropy change (-Δ S M max ) to be 4.69 J kg −1 K −1 and the relative cooling power to be 233.9 J kg −1 for a μ 0 Δ H =5 T magnetic field variation. These results indicate that LSSMO can be considered as a potential candidate material for application in magnetic refrigeration above room temperature. The critical behavior near the T C was studied through the analysis of the magnetic field dependence of the magnetic entropy change and Widom's scaling relation. The exponent values estimated in this work are fairly close to those theoretically predicted by mean field theory ( β =0.5, γ =1.0, and δ =3.0), revealing that long-range FM ordering exists in LSSMO. Scaling law theory also confirms the validity of the deduced critical exponents.

N-Phenyl-1-naphthylamine (P1NA) and N-Phenyl-2-naphthylamine (P2NA) are both widely used as antioxidant and plant secondary metabolites. In this study, growth, esterase, photosynthetic activity and cell membrane integrity were used as biomarkers to compare biotoxicity of P1NA and P2NA on Microcystis aeruginosa. According to the results, a dose-response relationship was observed only between P1NA concentrations and growth inhibition. The EC50 (48 h) of P1NA calculated from growth inhibition was 16.62 μM, while that of P2NA was not detected. When the esterase and photosynthetic activity were applied to evaluate the biotoxicity, it was found that a concentration of 20 μM P1NA, P2NA caused reduction of esterase activity and Fv/Fm of M. aeruginosa to 22.2 and 3.3%, 97.5 and 92.1%, respectively, after 48 h exposure. The percentage of membrane-damaged cells was increased as P1NA exposure concentration increased, but that was not detected when exposure to P2NA. The difference substituted position in the molecular structure of P1NA and P2NA leads to different toxicological properties and only P1NA was found highly toxic to M. aeruginosa. The toxicity is due to that only P1NA can be biotransformed to 1,4-naphthoquinone, which could induce overproduction of intracellular ROS as well as result in oxidative damage and growth inhibition of test organism.

This finite element (FE) study of lumbar biomechanics aims to predict how the parameters like range of motion (ROM), intervertebral disc pressure (IDP), cage stress and screw stress are affected by different direction-changeable cage positions. Firstly, the three-dimensional FE model of L3-L5 segment was developed, and the model was adjusted to adapt different direction-changeable cage positions at the L4-L5 level though transforaminal lumbar interbody fusion (TLIF) with pedicle screws. The effects of Type A (the lateral region), Type B (the lateralcentral region) and Type C (the anteriocentral region) on ROM, IDP, cage stress and screw stress were examined. The results showed that after implantation of interbody cages at different positions, the ROM at surgical level L4-L5 decreased substantially in all motion modes. The maximal stress in cage decreased with Type A, B and C in all motion modes except flexion and extension. The maximal cage stress was observed in Type A with 720.5 MPa in left rotation, in Type B with 707 MPa in flexion, in Type C with 397.3 MPa in left rotation, respectively. The maximal IDP was similar in three types, with 1.6 MPa in left lateral bending in Type A, 1.5 MPa in flexion in Type B, and 1.4 MPa in flexion in Type C. The range of screw peak stress was 16.4 to 61.1 MPa in Type A, 15.9 to 50.9 MPa in Type B, and 14.6 to 46.1 MPa Type C. In conclusion, comparing the cages with different positions, anteriocentral position cage has more advantages like lower cage stress, ODL and screw stress.

A new kind of hybrid plasmonic waveguide is proposed, and its propagation properties are investigated using the finite-element method. This waveguide consists of a V-shaped silver nanowire embedded in a low-index dielectric cladding above a semiconductor substrate, which can confine light in the subwavelength region with a long propagation length. The field distribution, the mode effective index, the propagation length, and the normalized mode area of the hybrid mode supported by the waveguide are investigated at the wavelength of 1550 nm, which are dependent on the geometric parameters.

Background: Intrahepatic cholestasis of pregnancy (ICP) is a common complication in the third trimester of pregnancy, which may result in premature delivery, fetal distress, stillbirth, and other adverse pregnancy outcomes. Ursodeoxycholic acid (UDCA) is a first-line treatment for ICP and has been controversial in improving adverse pregnancy outcomes. The purpose of this protocol is to systematically evaluate the effect of UDCA on pregnancy outcomes in patients with intrahepatic cholestasis during pregnancy. Methods: To search the databases PubMed, Embase, Web of Science, the Cochrane Library, CNKI, WanFang, VIP, CBMDIsc by computer, then to include randomized controlled clinical studies on UDCA for treatment of intrahepatic cholestasis during pregnancy from the establishment of the database to October 1, 2020. Two researchers independently extract and evaluate the data of the included studies, and meta-analysis is conducted on the included literatures using RevMan5.3 software. Results: This protocol evaluates the outcome of UDCA in improving ICP by incidence of postpartum hemorrhage in pregnant women preterm birth rates meconium contamination rate in amniotic fluid incidence of fetal distress scale of newborns scoring

This investigation demonstrates that programmed cell death (PCD) in a cyanobacterium, Microcystis aeruginosa, resulting from allelopathic stress induced by a submerged macrophyte, Myriophyllum spicatum, in a co-culture system. The hallmarks of PCD, caspase-3-like protease activity, DNA fragmentation, and destruction of cell ultrastructure, as well as intracellular PCD signaling radicals, reactive oxygen species (ROS), and nitric oxide (NO), were measured in M. aeruginosa cells co-cultured with M. spicatum for 7 days. The results showed a dose–response relationship between M. spicatum biomass and M. aeruginosa mortality. A caspase-3-like protease was activated and elevated from day 3. Thylakoid disintegration, cytoplasmic vacuolation, and fuzzy nuclear zone were observed by transmission electron microscopy, and distinct DNA fragmentation was detected in M. aeruginosa cells at a M. spicatum biomass of 6.0 g fresh weight (FW) L−1 during the 7 days. Allelochemicals of total phenolic compounds (TPCs) were determined in co-culture water, and the concentration increased with increasing of M. spicatum biomass and co-culture time. Compared with the level of ROS production in the control group, a significant overproduction of ROS was detected in M. aeruginosa cells in the treatment group, and this was positively correlated with TPC concentration. Furthermore, the level of intracellular NO increased with the percent mortality of M. aeruginosa. The results indicated that a PCD pathway was induced in the cyanobacterium M. aeruginosa when co-cultured with the submerged macrophyte M. spicatum.

A metal-insulator-metal (MIM) waveguide with double overlapping annular rings is proposed, and its transmission properties are simulated and characterized by the finite element method. The results show that the transmission valley appears in the transmission spectra when the straight MIM waveguide output port has a positional angular deviation θ relative to the incident port. Compared with the symmetric structure (θ = 0°), the filtering properties of the asymmetric structures (θ > 0°) are greatly improved. And compared to the MIM waveguide with single ring resonator, the filter characteristic of MIM waveguide with the double overlapping rings is superior to that of single ring resonator. For the asymmetric structure, due to the fact that parts of coupled MIM waveguide output port locates at the magnetic nodes of the standing waves in the ring resonator, there is a transmission minimum. Moreover, the asymmetric MIM waveguide can easily detect the refractive index changes of the filled media inside of resonator cavities, its potential applications in sensors.

Asymmetric transmission (AT) has significant applications in optical polarization control. In this paper, we propose a kind of periodic nanoslit rather than the protruding planar structures, such as G-shaped structure and coupled split-ring resonators, to realize the AT effect. The planar periodic obliquely intersecting nanoslits (OINs) in the gold film, composed of gratings with an infinite length and tilted nanoslits with a finite length, are proposed to realize the AT effect by performing the finite element method. Obvious dips in the AT spectra result from the circular localized surface plasmon resonance around the two terminals of the tilted nanoslits and from the surface plasmon polariton resonances on the film and in the gratings or tilted nanoslits. In addition, the AT effect strongly depends on the geometric parameters of the OINs. The film can be straightly powered on as an in-plane electrical conductor, which broadens its applications in optoelectronic devices. Overall, these results are beneficial in designing devices to achieve AT for polarization transformation.

Pyrogallic acid (PA) is used in various industrial and consumer products. The molecular mechanisms underlying PA's toxicity was not fully understood. In this study, toxicity of PA on Microcystis aeruginosa with reactive oxygen species (ROS) generation as an end point was investigated. The results showed an increase in the percentage of cells with loss of membrane integrity and enhanced intracellular ROS production. Exposure to 50mgL(-1) PA for 48h caused the highest percentage of loss of membrane integrity (56.7%), and a 2.54-fold higher intracellular ROS level compared to control. Further investigation revealed that PA caused a dose-dependent increase in DNA strand breaks (DSB) of M. aeruginosa at exposure concentration from 2 to 50mgL(-1). The incubation of cells with ROS scavengers ascorbic acid, N-acetyl-l-cysteine (NAC) and tocopherol markedly alleviated the level of PA-induced DSB. Analysis of PA autoxidized products in culture solution showed that PA was quickly converted to purpurogallin (PG), and PG was further autoxidized to other polyphenolic compounds. PA and PG might participate a futile redox cycle, which mediated ROS production in M. aeruginosa. These results suggested DNA strands and cell membrane were two targets of ROS induced by PA, and oxidative damage was an important mechanism for the toxicity of PA against M. aeruginosa.

Constructed wetlands (CWs) have been used in ecological engineering for more than two decades, since 1990. In order to understand the present application and trend of CWs in China, this paper summarized the status quo, prospect and influencing factors in CWs construction, technology application and operation management in China, according to the data obtained by literature survey. Results of the systematic survey showed that CWs technology achieved gradual perfection under pushes of national policies, market demand and technical feasibility, with the capacity of wastewater treatment increasing year by year. However, there were still some problems concerning engineering operation and management. Moreover, the results demonstrated that limited by the economic level, the degree of industrialization and urbanization, climatic conditions as well as land availability, CWs were distributing predominately in the region of 20 degrees 13'N-35 degrees 20'N in China, where covered the central areas with a subtropical monsoon climate and southern or central areas at province level. In these areas, there were more than 40 plant species, which accounted for 57.14% of the total number of common wetland plants. Most of the CWs composted series or parallel combination forms of the vertical flow and free water surface flow CWs units, and they were suitable to treat more than 20 different types of wastewater. For these CWs, the effluent chemical oxygen demand (COD), biological oxygen demand (BOD). total nitrogen (TN) and total phosphorous (TP) reached in the ranges of 20-60 mg/L, 4-20 mg/L, 1-20 mg/L and 0.2-1 mg/L, respectively. The effluents from CWs were reused in more than eight ways, such as for agricultural irrigation, supplying surface water, green belt sprinkling, etc. (C) 2012 Elsevier B.V. All rights reserved.

An exploratory study on the management of undesirable cyanobacteria blooms with respect to off-flavor problems using an integrated vertical-flow constructed wetland (CW) was performed at a small commercial-scale channel catfish farm from 2004 to 2007. The results of the three-year experiment indicated that water treatment by the CW could reduce the possibility of dominance by undesirable cyanobacteria species that often cause off-flavor problems. A detailed investigation in 2007, showed that the concentrations of geosmin, MIB (2-methylisoborneol), and beta-cyclocitral in the water of the recirculating pond (4.3 ng L(-1), U.D. (undetected) and 0.2 ng L(-1), respectively) treated by the CW were significantly lower than those in the control pond (152.6 ng L(-1), 63.3 ng L(-1) and 254.8 ng L(-1), respectively). In addition, the relationships among the cyanobacteria species, the off-flavor compounds and ten environmental variables were explored by canonical correspondence analysis (CCA). The results showed that Oscillatoria sp., Oscillatoria kawamurae and Microcystis aeruginosa were the main sources of off-flavor compounds in the catfish ponds. The successful manipulation of undesirable cyanobacteria species potentially resulted in lower concentrations of odorous compounds in the water of the recirculating pond. An investigation of the concentrations of geosmin and MIB in catfish fillets showed that the levels of odorous compounds were below the OTC (odor threshold concentration) values in the recirculating pond but were above the OTC values from July to October in the control pond. Water recycling by the CW could potentially be one of the best management practices to control off-flavor occurrences in aquaculture. (C) 2011 Elsevier Ltd. All rights reserved.

Asymmetric transmission (AT) is widely used in polarization transformers and polarization-controlled devices. In this paper, a planar metamaterial nanostructure with connected gammadion-shaped nanostructure (CGN) is proposed to achieve AT effect for forward and backward propagations of circular polarized light. The CGN arrays can produce magnetic moment oscillation that is normal to the metamaterial plane, which is weakly coupled to free space and generates transmission valleys. The introduction of symmetry breaking exerts a strong influence on the AT effects, and these effects can be tuned by the structural parameters. Our planar metamaterials may have potential for application in the future design of polarization-controlling devices.

Objectives To explore the longitudinal effect of metabolic syndrome (MetS) and its components on the development of non-alcoholic fatty liver disease (NAFLD) and to evaluate the significance of MetS and its components as early markers of NAFLD risk in a northern urban Han Chinese population. Materials and methods A total of 15,791 cohort members without NAFLD at baseline were included in the current study between 2005 and 2011. The baseline characteristics of the cohort were compared by MetS status at baseline and NAFLD status after follow-up. Cox proportional hazards models were used to estimate the unadjusted or adjusted hazard ratios (HRs) for development of NAFLD among individuals with MetS compared with individuals without MetS at baseline. Results During 51,652 person-years of follow-up, 3913 (24.78%) new cases of NAFLD occurred between 2005 and 2011. In the unadjusted model, the HR (95% confidence interval [CI]) for NAFLD was 2.51 (2.30, 2.73). After adjusting for gender, age, diet, smoking status, and regular exercise, the HR was 1.94 (1.78, 2.13). Gender differences were observed, with adjusted HRs (95% CIs) of 1.89 (1.71, 2.09) and 1.72 (1.43, 2.07) among males and females, respectively. Compared with individuals without MetS components, the HRs were 1.92 (1.76, 2.09), 2.64 (2.40, 2.90) and 3.51 (3.15, 3.91) for individuals with one, two, or three or more MetS components, respectively. Moreover, participants with obesity or hyperlipidemia had a higher risk of NAFLD than patients with hypertension or hyperglycemia, with HRs of 2.03 (1.83, 2.25) for obesity, 1.94 (1.72, 2.19) for hyperlipidemia, and 3.01 (2.68, 3.37) for these factors in combination. Conclusion The present study indicates that MetS and its components independently predict the risk of NAFLD in a northern urban Han Chinese population and suggests that people with MetS or its component should initiate lifestyle changes to prevent the development of NAFLD.

Green-lipped mussels, Perna viridis, were exposed to 0, 0.3, 3 and 30 μg l −1 (nominal concentrations) B[a]P under laboratory conditions over a period of 24 days. Mussels were collected on day 0, 1, 3, 6, 12, 18 and 24, and the levels of DNA adducts and DNA strand breaks in their hepatopancreas tissues monitored. Mussels exposed to 0.3 and 3 μg l −1 B[a]P showed marked increases in strand breaks after 1 day of exposure. DNA strand break levels in these mussels remained high and significantly different from the control values until day 3 for the 0.3 μg l −1 treatment group, and day 6 for the 3 μg l −1 treatment group. This was followed by a gradual reduction in strand breaks. After 12 days, the levels of both groups had returned to the same level as that of the control. No increase in DNA strand breaks was observable in mussels exposed to 30 μg l −1 B[a]P in the first 12 days of exposure, but a significant increase was observed from day 12 to day 24. Increasing B[a]P concentrations resulted in elevated DNA adduct levels after 3–6 days of exposure, but this pattern of dose-related increase disappeared after 12 days. These results indicate that a better understanding of the complex interactions between exposure levels and durations is crucially important before DNA adduct levels and DNA strand breaks in P. viridis can be used as effective biomarkers for monitoring genotoxicants in marine waters.