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The nectar of Camellia reticulata Lindl. contains sugar, amino acids and other nutritional components, suggesting that it could be developed for food and food additives. To understand the effects of the nectar on human health, we investigated its chemical constituents. Two new flavonoid glycosides, cameretiins A and B (1 and 2), and two known flavonoid glycosides, kaempferol 3-O-(2''-O-E-p-coumaroyl)-β-D-glucopyranoside (3) and tiliroside (4) were obtained from the nectar of Camellia reticulata Lindl. Their structures were determined based on analysis of their spectroscopic data and by comparison with 1D NMR spectroscopic data of known compounds reported in the literature. Compounds (1-4) were first isolated from the nectar of Camellia reticulata Lindl.

Femtosecond laser micromachining is a hot topic in the field of micromachining. Femtosecond laser processing of biomacromolecular micro devices has a promising application prospect. The research content of this paper is femtosecond laser micromachining of biomacromolecule materials, aiming at exploring the mechanism of femtosecond laser micromachining. In this paper, the principle of the interaction between laser and polymer materials is briefly expounded, and the photophysical processes such as transition, energy conversion, energy transfer and electron transfer are explained from the molecular orbital, and the mechanism is classified as photothermal and photochemical action, which is manifested as accelerating material's relaxation transformation process and degradation process. The interaction between polymer materials and laser starts from molecules absorbing the energy of photons to complete the transition from ground state to excited state. Different modes of excitation state inactivation correspond to the conversion of light energy into light energy, heat energy or chemical energy. On the one hand, the thermal action leads to the viscoelastic transformation of the material, and the material deforms or flows under the thermoelastic action; on the other hand, the thermal action accelerates the degradation reaction of the polymer material. The carbonyl group on the molecular chain of PMMA and PLA is more likely to reach the excited state, and the chemical properties of the carbonyl excited state determine that the photochemical processes of PMMA and PLA concentrate on the carbonyl group.

In this study, we report a systematical investigation regarding the ring size effects of meso-epoxides on reactivity and enantioselectivity as well as crystallization and degradation of the polycar...

The activation of oxygen (O2) under room condition is highly desirable for oxidative removal of organic pollutants in water. Herein, we report a graphite felt (GF)-supported α-MnO2 catalyst which is active for activating O2 with assistance of an anodic electric field. The electro-assisted catalytic wet air oxidation (ECWAO) process on MnO2/GF is able to rapidly degrade a variety of dyes, pharmaceutics and personal care products (PPCPs) under room condition. The congo red, basic fuchsin, neutral red and methylene blue are completely mineralized in 160 min, and the bisphenol A, triclosan and ciprofloxacin are mineralized by 89.9%, 81.5% and 65.4%, respectively, in 300 min. Mechanistic study indicates a surface-catalyzed non-free radical pathway for the oxidation of organic pollutants by O2 in the ECWAO process. The oxygen vacancies on MnO2 are identified as the catalytically active sites, at which oxygen atom is transferred from O2 to organic molecule through chemisorbed oxygen species. The anodic electric field assists such an oxygen transfer pathway by activating the complex of chemisorbed oxygen species and organic molecule through electro-oxidation reaction. The ECWAO process on MnO2/GF electrode exhibits a great potential for practical wastewater treatment under room condition.

The nectar of

Environmentally friendly and economically feasible technology is urgently needed for the management of phenolic compounds. Here, low-voltage degradation of phenol is achieved in an anodic oxidation (AO)-assisted O2 oxidation process with Fe3O4/graphite felt (GF) composite anode. Batch experiments on phenol degradation at 0.6 V achieve phenol removal in 78 h, and the total mineralization of phenol is obtained in 90 h at the first cycle. The time required for phenol removal is reduced to 48 h after three cycles of operation, meanwhile mineralization of phenol being completed in 51 h. The AO-assisted O2 oxidation process is confirmed to adopt a non-radical pathway in which the phenol is degraded at the catalytic sites of GF under the synergy of O2 and anodic electric field. Phenol degradation efficiency at the Fe3O4/GF composite anode is significantly higher than that at the GF, which is ascribed to the accelerated electron transfer by Fe3O4. The Fe C and Fe O C bonds are identified as inherent linkages responsible for electron transfer between the Fe3O4 and GF. Process efficiency is able to be spontaneously enhanced in recycling operation due to the intensification of Fe C and Fe O C bonds. The low energy cost and application of cheap carbonaceous anode endow the AO-assisted O2 oxidation process with great potential for use in the remediation of phenol pollutant.

Additional file 3: Figure S2. The swimming motility of wild-type KJ, phoP mutant (KJΔPhoP), phoPQ mutant (KJΔPhoPQ), and complementation strain (KJΔPhoPQ (pPhoPQ)). The logarithmic-phase bacterial culture was adjusted to OD450nm of 1.0. Five-microliter suspension was inoculated into the swimming agar (1% tryptone, 0.5% NaCl, and 0.15% agar) and the swimming zones were recorded after 48-h incubation at 37 °C.

Additional file 1: Table S1. Bacterial strains, plasmids, and primers used in this study.

Additional file 2: Figure. S1. SDS-PAGE and Western blotting of total bacterial proteins of S. maltophilia KJ, its derived mutants, and complementary strains. Overnight culture of bacterial cells was inoculated into fresh LB with an initial OD450nm of 0.15. Cells were grown aerobically for 5 h. Whole bacterial cell lysates were denatured and separated by 14% SDS-PAGE. (A) The gel was stained with 0.1% Coomassie Blue R250 in 10% acetic acid, 50% methanol, and 40% H2O for 30 min, and then destained with 10% acetic acid, 50% methanol, and 40% H2O until the background was clear. (B) The proteins in the gel were transferred onto polyvinylidene difluoride (PVDF) membranes. The blot was reacted with anti-PhoP antibodies and secondary mouse anti-rabbit IgG immunoglobulin conjugated to horseradish peroxidase (Sigma Chemical Co., St. Louis, MO). M, protein markers; lane 1, E. coli (pETPhoP); lane 2, KJ; lane 3, KJΔPhoP; lane 4, KJΔPhoP (pPhoP); lane 5, KJΔPhoP (pPhoPQ); lane 6, KJΔPhoPQ; lane 7, KJΔPhoPQ (pPhoP); lane 8, KJΔPhoPQ (pPhoQ); lane 9, KJΔPhoPQ (pPhoPQ). The cropped image presented in Fig. 2b is marked by a black rectangle.

Additional file 4: Figure S3. The secreted protease activity of wild-type KJ, phoP mutant (KJΔPhoP), phoPQ mutant (KJΔPhoPQ), and complementation strain (KJΔPhoPQ (pPhoPQ)). The logarithmic-phase of bacterial culture was adjusted to OD450nm of 1.0 and 40 μl bacterial aliquot were inoculated into the skim milk agar plate. The proteolytic activity of bacteria was assessed by measuring the transparent zones around the bacteria after incubation for 72 h at 37 °C.

Additional file 5: Figure S4. The expression of oxidative stress alleviation-associated genes of S. maltophilia KJ in response to MD challenge. Overnight culture of KJ cells was inoculated into fresh LB broth without or with MD (16 μg/ml) at an initial OD450nm of 0.15. Cells were grown aerobically for 5 h before measuring the indicated transcripts using qRT-PCR. All values were normalized to the transcript of MD-non-treated KJ cells. Bars represent the average values from three independent experiments. Error bars represent the standard error of the mean. *, P

A D-type fiber optic refractive index sensor based on surface plasmon resonance (SPR) principle is proposed in this paper. The sensor is composed of a double core structure and a grid-coated photonic crystal fiber (PCF) on the polishing surface. The resonant wavelength can be adjusted and the refractive index sensitivity can be improved by introducing a gold grating film. Under the anisotropic perfect matching layer boundary condition, the simulation was preformed through the full-vector finite element method (FEM). The results show that the refractive index measurement range of the sensor is 1.30~1.33, the sensitivity can reach 12000 nm• RIU-1, and the resolution can reach 1.01×10-5 RIU.

Objective: To explore the clinical efficacy of transforaminal endoscopic discectomy using TESSYS technique in the treatment of lumbar disc herniation (LDH). Methods: A total of 60 patients with LDH who were admitted in our hospital from June, 2014 to February, 2016 were included in the study and randomized into the study group and the control group. The patients in the study group were performed with transforaminal endoscopic discectomy using TESSYS technique, while the patients in the control group were performed with the vertebral lamina fenestration. VAS was used to evaluate the pain relieving before operation, 1 d, 1 month, 3 months, and 6 months after operation. The fasting elbow venous blood before operation, 3, 6, 12, 24, and 48 h after operation was collected. The immune scatter turbidity was used to detect hs-CRP. ELISA was used to detect IL-6. Results: The difference of VAS scores before operation between the two groups was not statistically significant (P>0.05). With the time extending after operation, VAS score was significantly reduced (P0.05). The difference of hs-CRP and IL-6 before operation between the two groups was not statistically significant (P>0.05). The levels of hs-CRP and IL-6 after operation at each timing point in the study group were significantly superior to those in the control group (P

The activation of oxygen (O

The electro-assisted catalytic wet air oxidation (ECWAO) process is effective for pollutants removal, by taking advantage of an anodic electric field to activate O2 on a catalyst surface. Herein, three different manganese oxides, including MnO2, Mn3O4 and MnO, are fabricated on graphite felt (GF) support to serve as the catalysts of ECWAO reaction. Structural properties of these manganese oxides are analyzed, and their catalytic behaviors in ECWAO reaction are investigated with bisphenol A as a probe pollutant. The manganese centers on the surface of manganese oxides are found to be present in multi-valence states, favoring the formation of chemisorbed oxygen species which are responsible for pollutants oxidation in the ECWAO process. Therefore, the manganese oxides demonstrate good and stable activity for catalytic oxidation of bisphenol A under room condition. The sequence of their catalytic activities is as follows: Mn3O4 > MnO > MnO2, depending on their low-temperature reducibility and oxygen mobility in them. These results illustrate a guideline to the design of highly active manganese oxide catalysts for the ECWAO reaction.

Supplemental material, Supporting_Information for A metal-free aerobic oxidative bromination of anilines and aryl ketones with 2-methylpyridinium nitrate as a reusable ionic liquid by Ming-Fang Li, Jian Wang, Yong-Xin Ke, Song-Cheng Pan, Hong Yin, Wenting Du and Jing-Hua Li in Journal of Chemical Research

The regulation of population density is suggested to be indirect and occurs with a time-lag effect, as well as being female centred. Herein, we present a quantitative analysis on the precise, timely and male-dominated self-regulation of Chinese alligator ( Alligator sinensis ) populations. Analysis of 31 years of data revealed gender differences in regulation patterns. Population dynamics were restricted by male density rather than population density, and population growth was halted (birth rate = 0) when male density exceeded 83.14 individuals per hectare, until some males were removed, especially adult males. This rapid and accurate response supports the notions of intrinsic mechanisms and population-wide regulation response. Furthermore, density stress affected mating success rather than parental care to juveniles, i.e. females avoided unnecessary reproduction costs, which may represent an evolutionary advantage. Our findings highlighted the importance of further studies on related physiological mechanisms that focus on four characteristics: quantity breeds quality, gender differences, male density thresholds and nonlinearity.

The Chinese alligator Alligator sinensis is one of the most endangered crocodilian species, and typically exhibits temperature-dependent sex determination. It is extremely important to clarify the sex structure of Chinese alligators to implement recovery projects successfully. However, the sex ratio of wild Chinese alligators remains unknown. In this study, we collected 28 years of sex ratio data from Chinese alligators residing in the natural and artificial habitats of Changxing Nature Reserve, China, and examined the differences in the sex ratio dynamics between these two populations. We observed that the sex ratio of wild Chinese alligators is 1 male to 4.507 females, which was significantly lower compared to that of the captive population (1 to 2.040; P < 0.001), and is significantly different to previously documented sex ratios for this species (all P < 0.01). Furthermore, we documented an annually stable (P = 1.000) female-biased sex ratio for wild alligators at hatching [1 male to 4.747 females; 0.174 (0.167–0.182)], in contrast to a dramatically fluctuating sex ratio (P < 0.001) in captivity [1 male to 1.674 females; 0.374 (0.246–0.593)], showing a potential mechanism for adjusting the sex structure. Finally, we found that the hatchling sex ratios were similar to that of the population sex ratio (P = 0.748), with little correlation to air temperature values in the 60–70 day incubation period during the breeding season (July and August; both P > 0.05). Overall, this study indicates that the stabilized female-biased sex ratio of Changxing Chinese alligators might result from selection pressure caused by local mate competition and major inbreeding.

Electrochemical determination of dopamine (DA) in the presence of ascorbic acid (AA) was achieved on boron-doped diamond (BDD) film electrode by differential pulse voltammetry. The experimental results indicated that the oxidative peaks of DA and AA could be separated completely on anodically-treated (BDD) electrode without further modification, although these two peaks can not be separated on glassy carbon electrode. The peak separation of DA and AA was developed to be 0.44 V. High sensitivity was obtained to determine DA selectively with the coexisting of a large excess of AA in acidic media by DPV. The detection limit of DA was achieved to be 1.1 × 10-6 M in the presence of AA with the concentration of 200 times more than DA. This technique was also applied to the determination of DA in real samples.

To explore the clinical and radiological outcomes of Discover artificial cervical disc arthroplasty and the range of motion status on adjacent segments for cervical spondylosis causing radiculopathy or myelopathy.A total of 18 consecutive patients underwent cervical arthroplasty with the Discover artificial cervical disc at our hospital. Clinical and radiological follow-ups were conducted. Their radiographic parameters of treatment and adjacent segments were evaluated at Month 1, 3, 6, 12, 18 post-operation. And the Japanese Orthopedic Association (JOA) score, visual analog scale (VAS) pain score and Odom's scale were recorded and analyzed.During follow-ups over an average of 15 months, there was no occurrence of vascular injury, severe complications or prosthesis displacement and loosening. The score of JOA was 7.2±1.8 at preoperation and 16.7±4.5 at postoperation. And the score of VAS was 8.15±1.65 at preoperation and 2.03±1.12 at postoperation.Discover artificial cervical disc arthroplasty is efficacious and the patients recover quickly. Targeted cervical segments may be stabilized and their physiological ranges of motion preserved.

To evaluate the efficacy and safety of minimally invasive percutaneous pedicle screw for the management of neurologically intact patients with thoracolumbar burst fractures and posterior ligamentous complex injuries.In the study, 35 patients were reviewed,including 20 males and 15 females, with an average age of 34.1 years (18 to 52), and the mean follow-up for 25.8 months (24 to 36).The duration of surgery was (95.8±12.3) minutes and intraoperative blood loss was (83.0±40.7) mL. There were no major perioperative complications, with the exception of 2 patients who developed a superficial wound infection. LKA and VBH were significantly improved immediately after surgery (P0.001). No significant loss of correction was observed in all the patients(P0.05). Screw misplacement was observed in 9/140 (6.4%) and no patient showed neurological deficit as a result of screw misplacement.The minimally invasive percutaneous pedicle screw has a good clinical outcome in the treatment of thoracolumbar burst fractures with posterior ligamentous complex injury, which could maintain the fracture reduction effectively, and minimize the iatrogenic soft tissue injury.

To evaluate the early clinical efficacy of large soft-tissue wounds with intermittent vacuum sealing drainage.From March 2009 to June 2010, the study group was comprised of 56 patients treated with intermittent vacuum sealing drainage. There were 47 males and 9 females with a mean age of 37.5 years (range: 16 - 65). Intermittent vacuum sealing drainage was immediately used after an emergency operation. The mean duration of treatment was 2.5 weeks (range: 1 - 4). The granulation status was observed and wound dressing changed weekly.Among them, all wound surfaces were dry and granulation tissues brightly red. There was no deep infection. The mean healing durations of intermittent and continuous vacuum sealing drainage groups were (32 ± 4.5) and (37 ± 7.5) days respectively. And there was no statistical difference (P0.05).Intermittent vacuum sealing drainage promotes a rapid and copious production of granulation tissue over soft tissue wound. The patient suffering is minimal and the dressings are easy to manage.

To evaluate the outcomes of modified transforaminal lumbar interbody fusion in patients with lumbar disc herniation.Forty-six cases of lumbar disc herniation were treated by modified transforaminal lumbar interbody fusion. There were 32 males and 14 females with a mean age of 47 years old (range: 27 - 65). The mean course of disease was 7.5 years (range: 4 - 18). Eighteen cases were of single-level lumbar disc herniation, including L3/4 (n = 5), L4/5 (n = 8) and L5/S1 (n = 5). There were 28 cases with lumbar degenerative diseases at other levels. Preoperatively, the score of visual analogue scale (VAS) was 8.9 ± 1.3 and the score of Oswestry disability index (ODI) was 57.3 ± 5.2. All patients received a normal conservative treatment for at least 3 months with no therapeutic effect at pre-operation.Forty-six cases had an average follow-up of 20 months (range: 12 - 20). The operative duration was an average of 160 minutes (range: 120 - 180). And the average volume of intra-operative blood loss was 550 ml (range: 400 - 800). There was no severe complication. The symptoms became stable after three months. At 3 months postoperatively, the score of VAS was 2.0 ± 0.4 and the score of ODI 15.2 ± 3.4. And there were significant differences between preoperative and postoperative values (P0.05). The improvement rates of postoperative VAS and ODI were (80.1 ± 4.7)% and (73.6 ± 2.8)% respectively. All patients achieved lumbar interbody bone fusion at 12 months post-operation with a fusion rate of 100%. For the therapeutic effect, 34 cases were regarded as excellent, 8 good and 4 fair with an excellent/good rate of 91.3%. All patients began to walk with orthosis after 3 days and resumed their jobs and normal lives after 3 months.Modified transforaminal lumbar interbody fusion is effective for the treatment of lumbar disc herniation. Making a detailed operative plan on the basis of preoperative images and symptoms is essential.

To evaluate the long-term outcomes of surgical treatment of open fracture of talus.Sixteen patients with displaced open fractures of the talus, including 3 cases of type 1, 8 of type 2, 2 of type 3A, 2 of type 3B, and 1 of type 3C according to the Gustilo-Anderson classification system, 15 males and 1 female, aged 37.5 (21 - 48), were treated with open reduction and stable internal fixation within 6 - 8 hours after injury, and followed up for 3.2 years (3 - 6 years). There were 7 cases of pure displaced talar neck or body fracture and 9 cases of fractures associated with an ipsilateral pilon, ankle, and calcaneus totally that included 2 cases of type 2, 3 of type 3, and 1 of type 4 according to the Hawkins classification system modified by Canale.The union rate was 81% (13/16) with the average union time of 4.5 months. Three cases failed to heal and developed osteomyelitis, of which 2 were treated with late talectomy because of septic nonunion. One case underwent amputation below-the-knee because of instability and pain. Osteonecrosis developed after seven of the nineteen closed fractures, whereas posttraumatic arthritis developed after all nineteen. Osteonecrosis developed in 11 (68%), and posttraumatic arthritis developed in 13 of the 16 cases (85%). The average American Orthopaedic Foot and Ankle Society score of these patients was 43.7 points.Open fractures of the talus has a low union rate, a higher osteonecrosis rate, and substantially higher reoperation and infection rates. Posttraumatic arthritis is a more common complication than osteonecrosis following operative treatment. Open reduction and internal fixation are recommended for the treatment of open fractures of talus.