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Antifouling biocides may cause adverse effects on non-target species. This study aims to determine the distribution, sources, and ecological risks of antifouling biocides in the surface waters of the Qiantang River and its estuary in eastern China. The concentrations of total antifouling biocides were ranged from 12.9 to 215 ng/L for all water samples. Atrazine, diuron and tributyltin were the major compounds in the water bodies of the study area. The acute and chronic toxicity criteria for tributyltin, diuron and atrazine were derived for freshwater and saltwater, respectively, based on the species sensitivity distribution approach. The freshwater and saltwater criteria were slightly different, and the toxicity to aquatic organisms could be summarized as tributyltin > diuron > atrazine. The graded ecological risk rating showed that the long-term risk of TBT was significant in coastal waters. The pollution of TBT in the Qiantang River deserves further attention. • Antifouling biocides were analyzed in the Qiantang River and its estuary, China. • The acute and chronic toxicity criteria of tributyltin, diuron and atrazine for local species were derived. • Ecological risk of tributyltin, diuron and atrazine were evaluated. • Tributyltin should be paid more attention. [ABSTRACT FROM AUTHOR]

Ossification of the ligamentum flavum (OLF) is a rare disease that causes acquired thoracic spinal canal stenosis and thoracic myelopathy. The aim of this study was to investigate clinical outcomes of symptomatic thoracic OLF treated using posterior decompressive laminectomy. We retrospectively analyzed the medical records of 22 patients who underwent posterior decompressive laminectomy for symptomatic thoracic OLF. The surgical results were evaluated using the modified Japanese Orthopaedic Association (JOA) scoring system and Hirabayashi recovery rate. The intensity of pain was evaluated using a visual analog scale (VAS). The mean duration of follow-up was 35.6 months. The mean JOA score was significantly improved at final follow-up (9.18 ± standard deviation of 1.53 points [range, 6–11 points]) compared with before surgery (5.64 ± 2.04 points [range, 3–9 points]) ( P < 0.001). The mean Hirabayashi recovery rate was 65.49% (range, 20–100%). Recovery outcomes were excellent in nine patients, good in eight patients, fair in four patients and unchanged in one patient. No patient was classified as deteriorated. The VAS scores were 2.82 ± 3.08 before surgery and 0.59 ± 1.05 at final follow-up ( P = 0.001). Surgical complications, which resolved after appropriate and prompt treatment, included dural tear in five patients, cerebrospinal fluid leakage in one patient, immediate postoperative neurologic deterioration in one patient, epidural hematoma in one patient, and wound infection in one patient. Our findings suggest that posterior decompressive laminectomy is an effective treatment for symptomatic thoracic OLF and provides satisfactory clinical improvement, but surgery for thoracic OLF is associated with a relatively high incidence of complications. [ABSTRACT FROM AUTHOR]

In this study we synthesized medium-band gap, two-dimensional (2-D) conjugated polymers comprising electron-rich benzo[1,2- b :4,5-b′]dithiophene (BDT) units presenting conjugated thiophene (T) side chains and electron-deficient alkoxy-modified 2,1,3-benzooxadiazole (BO) moieties. We introduced various solubilizing substituents—linear alkyl, alkoxy, and alkythio units—on the thiophene side chains to obtain a series of 2-D conjugated D–π–A polymers: PBDTT-C-BO , PBDTT-O-BO , and PBDTT-S-BO . The solubilizing substituents of the BDT units altered the solubility, conformations, and electronic properties of the synthesized conjugated polymers, allowing tuning of the photovoltaic properties when blended with fullerenes. We investigated the effects of the different linear solubilizing substituents of the BDT units on the structural, optical, and electronic properties (e.g., band gap energies) of the resulting 2-D conjugated polymers, as determined from quantum-chemical calculations, UV–Vis absorption spectra, and grazing-incidence X-ray diffraction. Atomic force microscopy and transmission electron microscopy images revealed the morphologies of active layers comprising these 2-D conjugated polymers and the fullerene derivative [6,6]-phenyl-C 71 -butyric acid methyl ester (PC 71 BM). Through rational structural modifications of the solubilizing substituents in the 2-D conjugated polymers with alkoxy, alkythio or alkyl units, the resulting PCEs varied from 5.4 to 7.5%. A polymer solar cell based on a blend of PBDTT-C-BO and PC 71 BM exhibited the best photovoltaic performance among our three studied systems, with a high short-circuit current density ( J sc ) of 15.7 mA cm −2 and a power conversion efficiency of 7.5%, without the need for any processing additives or post-treatment processes, highlighting the importance of careful selection of appropriate solubilizing substituent that attached to the donor segments when designing efficient D–π–A polymers for use in solar cells. [ABSTRACT FROM AUTHOR]

Abstract: Esophageal perforation is an uncommon but potentially fatal complication of anterior cervical spinal surgery. This study aimed to investigate the diagnosis and treatment of cervical esophageal perforation related to spinal surgery. Among 1097 consecutive cases of anterior cervical spinal surgery that were managed at our institution over a 20year period, five patients with esophageal perforation were identified. We performed a retrospective review of the diagnoses and treatment of esophageal perforation in these five patients as well as another patient who was transferred from another hospital. The esophageal perforations in all six patients were recognized during the early postoperative period. All patients presented with neck pain, dysphagia, odynophagia, coughing, fever and incision swelling and drainage. Diagnosis was confirmed by one or several of the following methods: contrast swallow study; endoscopy; cervical radiographs; or oral methylene blue. Nasogastric tube, intravenous antibiotics, enteral and parenteral nutrition, and open drainage were conducted in all patients. The wound was debrided in three patients, while two had implant removal and primary suture of the perforation. Five patients had a good recovery with healing of the esophagus, while one patient died due to severe pneumonia. The early diagnosis of esophageal perforation related to cervical spinal surgery relies on clinical suspicion and efficient investigation. The selection of appropriate treatment options, which include esophageal rest, antibiotic administration, nutrition support, wound debridement, open drainage, and surgical repair, largely depends on when the perforation is recognized. Early diagnosis and prompt management of this complication are likely to result in a good clinical outcome. [Copyright &y& Elsevier]

Abstract: In this study we used Suzuki cross-coupling to synthesize three new donor/acceptor copolymers—PFTBO, PAFTBO, and PCTBO—featuring soluble alkoxy-modified 2,1,3-benzooxadiazole (BO) moieties as acceptor units and electron-rich building blocks—dialkyl fluorene (F), alkylidene fluorene (AF), and carbazole (C), respectively—as donor units. These polymers, which we characterized using gel permeation chromatography, thermogravimetric analysis, NMR spectroscopy, UV–Vis absorption spectroscopy, and electrochemical cyclic voltammetry, exhibited good solubility, low-lying energy levels for their highest occupied molecular orbitals, excellent thermal stability, and air stability. Using these polymers, we fabricated bulk-heterojunction solar cell devices having the structure indium tin oxide/poly(3,4-ethylenedioxythiophene):polystyrenesulfonate/polymer:[6,6]-phenyl-C61-butyric acid methyl ester (PC61BM) (1:1, w/w)/Ca/Al. Under AM 1.5G illumination (100 mW cm−2), the solar cell incorporating PFTBO exhibited a high value of V oc of 1.04 V and that based on PCTBO provided a power conversion efficiency of 4.1% without the need for any post treatment. [Copyright &y& Elsevier]

Abstract: Study design: Vertebral endplate tissues were obtained from patients with degenerated lumbar disc classified as Modic type 1 or type 2 and investigated with immunohistochemical staining and the DNA nick end labelling techniques. Objective: To examine the expression of fas receptor (FasR) and apoptosis in the endplate cells isolated from patients with degenerative disc disease and to see whether they are associated with the pathological change of endplate. Methods: Fifty-six degenerated lumbar endplate specimens were obtained from the patients with degenerative disc disease categorized as type Modic I or II in magnetic resonance imaging (MRI) and eight nondegenerated specimens as control (vertebra burst fracture patients without degenerative change in MRI) during surgical procedures. Immunohistochemical staining was performed to determine the presence of FasR and apoptosis in sections of those endplate tissues. To investigate whether the FasR expression and apoptosis in endplate were influenced by degeneration and ageing of the discs, the level of FasR expression and apoptosis in the changed and unchanged endplates was analysed. Results: FasR were expressed in the cytoplasm of the endplate cells. A higher degree of FasR expression and apoptosis in endplate cells in degenerated discs was found than that in nondegenerated discs. In cell culture, the level of FasR expression and apoptosis in cells from the degenerative endplates was higher than those in unchanged endplates. The percentage of FasR-positive endplate and apoptotic endplate cells correlated significantly with the patient''s age (r =0.301, p <0.05; r =0.307, p <0.05. respectively), but not with the degree of disc degeneration in MRI (r =0.047, p >0.05; r =0.066, p >0.05, respectively). Conclusion: This is the first study to compare the expression of FasR and apoptosis on vertebral endplate cells in degenerated disc with in nondegenerated disc. The results show that the endplate in degenerated disc may undergo fas-mediated apoptosis and vice versa, endplate degenerative changes may promotes apoptosis of the endplate cells within degenerated disc. [Copyright &y& Elsevier]

Abstract: A new unsymmetrical and concoplanar aromatic diamine monomer containing trifluoromethyl and dimethyl groups, 3,5-dimethyl-4-(4-amino-2-trifluoromethylphenoxy)-4′-aminobenzophenone (3), was synthesized in a three-step reaction using 2,6-dimethylphenol and 4-nitrobenzoyl chloride as starting materials. A series of fluorinated poly(ether ketone imide)s (PEKIs) (5a–d) were prepared from diamine 3 with four aromatic dianhydrides via a one-step high-temperature polycondensation procedure. The obtained PEKIs were readily soluble in some organic solvents and could be solution cast into flexible and tough films. These PEKI films exhibited high optical transparency with a cutoff wavelength of 354–375 nm and low dielectric constants (2.26–2.45 at 1 MHz). They also showed good thermal stability with glass-transition temperatures (T gs) above 289 °C, 10% weight loss temperatures in the range of 518–531 °C, and the weight residue more than 52% at 800 °C in nitrogen. Moreover, the PEKI films possessed tensile strengths and initial modulus ranged from 91 to −128 MPa and 1.7 to 2.4 GPa, respectively. Due to their properties, these fluorinated PEKIs could be considered as photoelectric and microelectronic materials. [Copyright &y& Elsevier]

Abstract: A series of branched poly(ethylene terephthalate) (BPET) samples were prepared from melt polycondensation by incorporation of various amount (0.4–1.2mol%) of glycerol as a branching agent. These polymers were characterized by means of H1 NMR, intrinsic viscosity. The general crystalline and melting behavior was investigated via DSC. It was found that the crystalline temperature T cc from the melt shifted to high temperature and the T hc from the glass got low for BPETs while the melting temperatures of BPETs kept almost unchanged. The kinetics of isothermal crystallization was studied by means of DSC and POM. It was found that the present branching accelerated the entire process of crystallization of BPETs, although prolonged the induced time. In addition, branching reduced nucleation sites; hence the number of nucleates for BPET got smaller. Therefore, more perfect geometric growth of crystallization and greater radius of spherulites could develop in BPET due to less truncation of spherulites. [Copyright &y& Elsevier]

Abstract: Conducting composites of polyacrylonitrile (PAN) copolymer containing 10% mass ratio methylacrylate and dodecylbenzene sulfonic acid doped polyaniline (PANI–DBSA) were prepared by solution blending. Electrical properties of the blends were characterized by means of electrical conductivity measurements and the phase structures were investigated via scanning electron microscopy (SEM), X-ray diffraction (XRD), FT-IR spectroscopy, differential scanning calorimetry (DSC) and dynamical mechanical analysis (DMA). It was found that the electrical conductivity of the composites increased with the increase of PANI–DBSA content and the percolation threshold lay around 3.2wt%. DSC and DMA measurements showed that there was only one T g for each blend and the values of T g varied with the PANI–DBSA content, implying that the PANI–DBSA/PAN blend was at least partially compatible. The formation of the hydrogen bonding between the carbonyl groups in PAN copolymer and the imine groups in PANI–DBSA was identified by the FT-IR spectra. XRD demonstrated that the intrinsic layered arrangement of PANI–DBSA was disaggregated in the blends. Nanosize network structure of PANI–DBSA dispersing in PAN matrix and the so-called phase reverse occurring in the skin layer of the film samples at low PANI–DBSA loading were observed by SEM. [Copyright &y& Elsevier]