Study on the preparation of granular alum sludge adsorbent for phosphorus removal.

Alum sludge is the sludge discharged from a sedimentation tank in a drinking water treatment plant when polymerized with poly-aluminum chloride (PAC). In this paper, granular alum sludge adsorbent (GASA) was manufactured using powdery alum sludge (PAS) as the raw material and methods such as gluing and pore-forming. The effects of different binders, pore-forming agents, roasting temperatures, and roasting times on the formation of GASA and its dephosphorization performance were investigated. Results showed that the optimum binder was AlCl3 at a mass ratio of 8%, and the best pore-forming agent was starch at a 4% dosage ratio. Meanwhile, the optimum roasting temperature and time were 500 °C and 2 hours, respectively. The specific surface area of GASA was 23.124 m2/g. Scanning electron microscopy suggested that GASA's surface became rough, particles became tight, and average pore size increased, with additional pore channels. P adsorption by GASA reached 0.90 mg/g. The effluent phosphorus concentration of actual tail water decreased to 0.49 mg/L and the removal rate reached 73.5% when the GASA dosage was 20 g/L. The findings of this study are important for the further development of a low-cost adsorbent material for P removal in the future.

Biodegradation of polyvinyl alcohol by different dominant degrading bacterial strains in a baffled anaerobic bioreactor.

Polyvinyl alcohol (PVA) is the main pollutant in printing and dyeing wastewaters. This pollutant exhibits great demand, poor biodegradability and refractory degradation. In this study, PVA wastewater treatment experiments were conducted in a stably operating baffled anaerobic bioreactor (ABR) by using simulated PVA wastewater. The PVA degradation pathway and mechanism of the mixed dominant PVA-degrading bacterial strains were identified through the analysis of their degradation products. From the results, we inferred that PVA was degraded in a stepwise process under the synergistic action of different extracellular and intracellular enzymes produced by the mixed dominant PVA-degrading bacterial strains. In this process, PVA was first degraded into ketones, fatty acids and alcohols. It was then regenerated into acetic acid, hydrogen and carbon dioxide. Finally, these substances could be further utilized by methanogens. PVA was thus degraded completely. This study may serve as a reference for future works on the degradation of PVA in the ecological environment. It may also guide the sustainable development of PVA.

[A study on the effects and safety of sequential humidified high flow nasal cannula oxygenation therapy on the COPD patients after extubation].

Objective: To investigate and compare the effect and safety of nasal high-flow oxygen therapy (HFNCO) and noninvasive ventilation (NIV) therapy after extubation in patients with chronic obstructive pulmonary disease (COPD). Methods: All COPD patients subjected to mechanical ventilation in the Emergency Intensive Unit of the First Affiliated Hospital of Zhejiang University during January 2015 to June 2016 were included in the study. The patients were divided into two groups after extubation and HFNCO and NIV were adopted on each group respectively. Clinical indexes including the patients' general condition, blood gas analysis and pulmonary function before and after extubation, ratio of re-intubation and CT grades were collected and analyzed. Results: There was no significant difference in the incidence of aspiration (4.8% vs 8.3%), pressure sores (0 vs 8.3%) and delirium (4.8% vs 12.5%) between the two groups (all P>0.05). At 12 h after extubation, the oxygenation index of NIV group was significantly higher than that of the HFNCO group (265±29 vs 297±33; P<0.05), while no significant difference in PCO(2) (P>0.05). For 24 h and 72 h after extubation, there was no statistically significant difference in oxygenation index and PCO(2) between the both groups (P>0.05). The intensive care unit (ICU) retention time in HFNCO group was significantly lower than that in NIV group (13.7±0.8 vs 15.2±0.5; P<0.05). In addition, no significant difference between the two groups in mortality and re-intubation rate at 28 d (P>0.05) was observed. Conclusion: HFNCO is effective and safe in the treatment of COPD patients after extubation, and it is hence valuable for further clinical application.

Multiple generations of high-order orbital angular momentum modes through cascaded third-harmonic generation in a 2D nonlinear photonic crystal.

We experimentally demonstrate multiple generations of high-order orbital angular momentum (OAM) modes through third-harmonic generation in a 2D nonlinear photonic crystal. Such third-harmonic generation process is achieved by cascading second-harmonic generation and sum-frequency generation using the non-collinear quasi-phase-matching technique. This technique allows multiple OAM modes with different colors to be simultaneously generated. Moreover, the OAM conservation law guarantees that the topological charge is tripled in the cascaded third-harmonic generation process. Our method is effective for obtaining multiple high-order OAM modes for optical imaging, manipulation, and communications.

Comparative proteomic analysis of different developmental stages of swamp buffalo testicular seminiferous tubules.

With ageing, many protein components change markedly during mammalian spermatogenesis. Most of these proteins have yet to be characterized and verified. Here, we have employed two-dimensional electrophoresis coupled to tandem mass spectrometry to explore the different proteins from pre-pubertal, pubertal and post-pubertal swamp buffalo testicular seminiferous tubules. The results showed that 25 protein spots were differentially expressed among developmental stages, and 13 of them were successfully identified by mass spectrometry. Of which four proteins were up-regulated and three proteins were down-regulated with age, and the remaining six proteins were fluctuated among developmental stages. Bioinformatics analysis indicates that these proteins were probably related to cellular developmental process (53.8%), cell differentiation (53.8%), spermatogenesis (15.4%), apoptotic process and cell death (30.8%). Expression profiles of calumenin (CALU) and galectin-1 (LGALS1) were further verified via Western blotting. In summary, the results help to develop an understanding of molecular mechanisms associated with buffalo spermatogenesis.

Comparison of Mitochondrial Function in Boar and Bull Spermatozoa Throughout Cryopreservation Based on JC-1 Staining.

BACKGROUND: Poor reproductivity hampers the commercialization of cryopreserved boar semen. OBJECTIVE: This study was to determine the differences in the sperm mitochondrial function between boar and bull semen at different cryopreservation stages. MATERIALS AND METHODS: Boar and bull fresh, equilibrated, and frozen-thawed spermatozoa were evaluated for mitochondrial function using JC-1 under a fluorescent microscope. RESULTS: Bull and boar percentage of spermatozoa staining green (PSSG) showed no difference between fresh and equilibrated semen (P> 0.05). However, frozen-thawed bull and boar semen demonstrated significantly higher PSSG (P < 0.01) than fresh and equilibrated semen. Frozen-thawed boar semen represented a significantly higher PSSG (P < 0.01) than bull semen. CONCLUSION: Negative cryopreservation influence on boar and bull spermatozoa was not significantly produced by pre-freezing procedures, but rather by freezing and thawing. Cryopreservation has more pronounced negative effects on boar than on bull spermatozoa, which partly explains lagged commercialization of frozen boar semen.

Fork gratings based on ferroelectric liquid crystals.

In this article, we disclose a fork grating (FG) based on the photo-aligned ferroelectric liquid crystal (FLC). The Digital Micro-mirror Device based system is used as a dynamic photomask to generated different holograms. Because of controlled anchoring energy, the photo alignment process offers optimal conditions for the multi-domain FLC alignment. Two different electro-optical modes namely DIFF/TRANS and DIFF/OFF switchable modes have been proposed where the diffraction can be switched either to no diffraction or to a completely black state, respectively. The FLC FG shows high diffraction efficiency and fast response time of 50µs that is relatively faster than existing technologies. Thus, the FLC FG may pave a good foundation toward optical vertices generation and manipulation that could find applications in a variety of devices.

Coupled orbital angular momentum conversions in a quasi-periodically poled LiTaO3 crystal.

We experimentally demonstrate the orbital angular momentum (OAM) conversion by the coupled nonlinear optical processes in a quasi-periodically poled LiTaO3 crystal. In such a crystal, third-harmonic generation (THG) is realized by the coupled second-harmonic generation (SHG) and sum-frequency generation (SFG) processes, i.e., SHG is dependent on SFG and vice versa. The OAMs of the interacting waves are proved to be conserved in such coupled nonlinear optical processes. As we increase the input OAM in the experiment, the conversion efficiency decreases because of the reduced fundamental power density. Our results provide better understanding for the OAM conversions, which can be used to efficiently produce an optical OAM state at a short wavelength.

Stability of the cytoskeleton of matured buffalo oocytes pretreated with cytochalasin B prior to vitrification.

Stabilizing the cytoskeleton system during vitrification can improve the post-thaw survival and development of vitrified oocytes. The cytoskeleton stabilizer cytochalasin B (CB) has been used in cryopreservation to improve the developmental competence of vitrified oocytes. To assess the effect of pretreating matured buffalo oocytes with CB before vitrification, we applied 0, 4, 8, or 12 µg/mL CB for 30 min. The optimum concentration of CB treatment (8 µg/mL for 30 min) was then used to evaluate the distribution of microtubules and microfilaments, the expression of the cytoskeleton proteins actin and tubulin, and the developmental potential of matured oocytes that were vitrified-warmed by the Cryotop method. Western blotting demonstrated that vitrification significantly decreased tubulin expression, but that the decrease was attenuated for oocytes pretreated with 8 µg/mL CB before vitrification. After warming and intracytoplasmic sperm injection, oocytes that were pretreated with 8 µg/mL CB before vitrification yielded significantly higher 8-cell and blastocyst rates than those that were vitrified without CB pretreatment. The values for the vitrified groups in all experiments were significantly lower (P < 0.01) than those of the control groups. In conclusion, pretreatment with 8 µg/mL CB for 30 min significantly improves the cytoskeletal structure, expression of tubulin, and development capacity of vitrified matured buffalo oocytes.

Isolation, proliferation, and induction of Bama mini-pig spermatogonial stem cells in vitro.

Spermatogonial stem cells (SSCs), the unique seed cells of testes, can undergo meiosis and form spermatozoa, thus transmitting genetic information to offspring. Research concerning these cells explores the mechanism underlying spermatogenesis, making possible the induction of their differentiation into spermatozoa in vitro. SSCs have therefore attracted much interest among scientists. Although the proliferation of such cells in vitro has been demonstrated, we are unaware of any long-term laboratory culture of porcine SSCs. The objective of this study was to isolate, characterize, culture, and induce the differentiation of Bama mini-pig SSCs. SSCs were isolated using differential plating and cultured for over 100 days on an STO feeder cell layer without serum. Cell clusters appeared after three passages and continuously formed during subsequent cultivation. Staining showed that these clusters were positive for UCHL1 and CDH1, could be bound by Dolichos biflorus agglutinin, and that some cells expressed OCT4. Ultrastructure observations revealed SSCs in testis tissue to be round in shape, while those cultured in vitro were flat and bound together. Our attempts at inducing differentiation showed that SSCs cultured in vitro could undergo meiosis. In this study, we describe an effective culture system for Bama mini-pig SSCs capable of producing enough cells to establish a platform for further SSC research, such as genetic manipulation or exploration of the mechanism underlying spermatogenesis.

Micro-patterned photo-aligned ferroelectric liquid crystal Fresnel zone lens.

In this Letter, we disclose a fast switchable Fresnel zone lens (FZL) by confining the ferroelectric liquid crystals (FLCs) in multiple microscopically defined photo-aligned alignment domains. The photo-alignment (PA) offers good control on the anchoring energy (W) by mean of irradiation doses (ID) and thus excellent alignment for FLCs. Two operational modes of the FLCFZL, i.e., FOCUS/OFF and FOCUS/DEFOCUS, were demonstrated. The proposed diffracting element provides fast response time, high diffraction efficiency (η), with saturated electro-optical (EO) operations up to high frequency (≈2 kHz). Thus, the proposed FLCFZLs with simple fabrication open several opportunities to improve the quality of existing devices and to find new applications.

Production of hGFAP-DsRed transgenic Guangxi Bama mini-pigs via somatic cell nuclear transfer.

The mini-pig is a useful animal model for human biomedical research due to its physiological similarity to humans and the ease of handling. In order to optimize the efficiency of production of transgenic Bama mini-pigs through somatic cell nuclear transfer (SCNT), we examined the effects of contact inhibition, roscovitine treatment, and serum starvation on the cell cycle synchronization and transgenic cloned embryo development in vivo and in vitro after nuclear transfer. The analysis showed that the rates of G0/G1 stage cells in the contact inhibition (92.11%) and roscovitine treatment groups (89.59%) were significantly higher than in serum starvation group (80.82%). A higher rate of apoptosis was seen in the serum starvation group (14.13%) compared to the contact inhibition and roscovitine treatment groups (6.71 and 2.46% respectively, P < 0.05). There was a significant decrease in blastocyst yield in the serum starvation group (14.19%) compared to the roscovitine treatment and contact inhibition groups (21.31 and 20.32% respectively, P < 0.05). A total of 1070 transgenic cloned embryos derived from the three treatment groups were transferred to surrogate sows; one pregnancy was established and three embryos from the roscovitine treatment group successfully completed gestation. These results indicate that the roscovitine treatment was more effective at synchronizing transgenic kidney cells in Bama mini-pigs and allowed reconstructed embryos to develop to full term.

[Diagnosis and treatment strategies of 56 cases of middle ear myoclonus].

Objective: To analyze the clinical characteristics and treatment of middle ear myoclonus. Methods: Fifty-six cases of middle ear myoclonus were enrolled in Shandong Provincial ENT Hospital, Shandong University from September 2019 to August 2021, including 23 males and 33 females. The age ranged from 6 to 75 years, with a median age of 35 years; Forty-seven cases were unilateral tinnitus, nine cases were bilateral tinnitus. The time of tinnitus ranged from 20 days to 8 years. The voice characteristics, inducing factors, nature (frequency) of tinnitus, tympanic membrane conditions during tinnitus, audiological related tests, including long-term acoustic tympanogram, stapedius acoustic reflex, pure tone auditory threshold, short increment sensitivity test, alternate binaural loudness balance test, loudness discomfort threshold, vestibular function examination, facial electromyography, and imaging examination were recorded. Oral carbamazepine and/or surgical treatment were used. The patients were followed up for 6-24 months and the tinnitus changes were observed. Results: Tinnitus was diverse, including stepping on snow liking sound, rhythmic drumming, white noise, and so on. The inducing factors included external sound, body position change, touching the skin around the face and ears, speaking, chewing and blinking, etc. Forty-four cases were induced by single factor and 9 cases were induced by two or more factors. There was no definite inducing factor in 1 case. One patient had tinnitus with epilepsy. One case of traumatic facial paralysis after facial nerve decompression could induce tinnitus on the affected side when the auricle moved. Tympanic membrane flutter with the same frequency as tinnitus was found in 12 cases by otoscopy, and the waveform with the same frequency as tinnitus was found by long-term tympanogram examination. There were 7 patients with no tympanic membrane activity by otoscopy, the 7 cases also with the same frequency of tinnitus by long-term tympanogram examination, but the change rate of the waveform was faster than that of the patients with tympanic membrane flutter. All patients with tinnitus had no change in hearing. One case of tinnitus complicated with epilepsy (a 6-year-old child) was treated with antiepileptic drug (topiramate) and tinnitus subsided. One case suffered from tinnitus after facial nerve decompression for traumatic facial paralysis was not given special treatment. Fifty-four cases were treated with oral drug (carbamazepine), of which 10 cases were completely controlled and 23 cases were relieved; 21 cases were invalid. Among the 21 patients with no effect of carbamazepine treatment, 8 patients were treated by surgery, 7 patients had no tinnitus after surgery, 1 patient received three times of operation, and the third operation was followed up for 6 months, no tinnitus occurred again. The other 13 cases refused the surgical treatment due to personal reasons. Conclusions: Middle ear myoclonus tinnitus and the inducing factors manifestate diversity. Oral carbamazepine and other sedative drugs are effective for some patients, and surgical treatment is feasible for those who are ineffective for medication.

Translocation of active mitochondria during buffalo (Bubalus bubalis) oocytes in vitro maturation, fertilization and preimplantation embryo development.

Mitochondria are energy-supplying organelles, whose distribution and functional integrity are necessary for cell survival and development. In this study, the mitochondrial distribution pattern and activity during buffalo oocyte in vitro maturation, fertilization and preimplantation embryo development were revealed using a fluorescent dye and confocal laser scanning microscopy. Distribution of active mitochondria changed during buffalo oocyte in vitro maturation. Active mitochondria were transferred from the outer to inner and perinuclear cytoplasm as oocytes matured in vitro and aggregated around the pronuclei in the fertilized eggs. Active mitochondria were also observed in preimplantation embryos. In the two-cell stage, they were distributed throughout the cytoplasm. From four-cell to the spherical embryonic stages, active mitochondria translocated to the perinuclear and the periphery of the cytoplasm. These results confirm that mitochondria play an important role in oocyte and embryo. The distribution of active mitochondria might be a marked feature of buffalo oocyte maturation, fertilization and preimplantation embryo development in vitro.

Protective effects of melatonin against oxidative stress in flow cytometry-sorted buffalo sperm.

Previous reports of the ability of melatonin to scavenge a variety of toxic oxygen and nitrogen-based reactants suggest that melatonin could be an effective antioxidant for protecting sperm. In this study, flow cytometry and laser tweezers Raman spectroscopy were used to evaluate the effect of melatonin on buffalo sperm quality to optimize sperm sex-sorting procedures. In fresh sperm incubated in the presence or absence of melatonin (10(-4) m) for 1, 24, 48 h or 72 h at 27°C, the mitochondrial activity was significantly higher than in a non-melatonin control (p < 0.05). Also, during the flow-sorting process, sperm in melatonin-supplemented groups had higher (p < 0.05) mitochondrial activity than the control. The intensity of Raman spectra from sperm frozen in media supplemented with melatonin was significantly weaker than that for non-melatonin-treated groups, except for a band at 1302 per cm. Thus, melatonin helps to protect buffalo sperm from reactive oxygen species induced by staining, sorting and freezing and increases semen quality after the freezing-thawing processes. Furthermore, the results indicate the high potential of the laser tweezers Raman spectroscopy technique for rapid, effective and non-invasive assessment of the quality of sperm cells.

[Comparative study on fracture toughness of digital light processing three-dimensional printing zirconia and milled zirconia].

Objective: To investigate the influence of digital light processing (DLP) and computer numerical controlmilling (CNC) on the mechanical behavior of zirconia. Methods: Prepared DLP samples (experimental group, n=52) and CNC samples (control group, n=52) with 12 samples in each group were randomly selected using random number table to measure density, grain size and crystal phase composition. According to the different methods fracture toughness test, the samples were divided into indentation method group (IM) and single-edge-V-notch-beam group (SEVNB), with 30 DLP and 30 CNC samples in IM group, 10 DLP and 10 CNC samples in SEVNB group. The IM group was tested under three different loads (49.03 N, 98.07 N, 196.10 N), there were 10 samples for each load and each sample was tested at 15 points, and the load with the ratio of crack length to indentation diagonal length greater than 2.5 was selected as the indentation load to calculate its IM fracture toughness. At the same time, the SEVNB group was tested with four point bending test to record the maximum load at the time of fracture and calculate the SEVNB fracture toughness. Finally, the indentation and fracture surface were observed using optical microscope and scanning electron microscope, and the results of DLP group and CNC group were further compared to explore the difference in fracture mechanism. Results: The microstructure of DLP and CNC zirconia was basically the same, the density of DLP group was (6.020±0.021) g/cm3, the grain size was (0.603±0.033) µm; the density of CNC group was (6.038±0.012) g/cm3, the grain size was (0.591±0.033) µm. Both groups were composed of tetragonal zirconia. The load of 196.10 N was chosen as the indentation load for two groups to calculate the IM fracture toughness. In terms of fracture toughness, there was no significant difference between the two groups (P>0.05). Scanning electron microscope images of fracture surface showed the intergranular fracture was the leading fracture mode of two groups. The IM and SEVNB fracture toughness of DLP zirconia were (6.111±0.179) MPa·m1/2 and (7.221±0.809) MPa·m1/2, respectively. The IM and SEVNB fracture toughness of CNC zirconia were (6.126±0.383) MPa·m1/2 and (7.408±0.533) MPa·m1/2, respectively. Conclusions: The microstructure of DLP and CNC zirconia is almost the same, and there is little difference in the fracture toughness of zirconia between two processing technologies.

Generation and characterization of embryonic stem-like cell lines derived from in vitro fertilization Buffalo (Bubalus bubalis) embryos.

In the present study, buffalo embryonic stem-like (ES-like) cell lines were successfully isolated, cultured and characterized. From a total of 92 normal buffalo embryos obtained by in vitro fertilization, 18 were morulae, 33 were blastocyst and 41 were hatched blastocyst, the inside of morulae or inner cell masses of blastocysts were isolated mechanically and cultured onto mitomocin-C-inactivated buffalo embryonic fibroblasts as feeder layers. Alkaline phosphatase (AP) of ES-like cells, as well as the specific stage embryonic antigen SSEA-1, SSEA-3, SSEA-4 and transcription factor OCT-4, was used to evaluate the characterization of the cells. The spontaneous differentiation of ES-like cells was induced by culturing on leukaemia inhibitory factor-free medium for more than 2 weeks without passage. To evaluate mark gene expression, total RNA was extracted from cells, and specific primers were used for reverse transcriptase-polymerase chain reaction (RT-PCR). After 8-10 days of culture, primary ES-like cell colonies were formed in 0% (0/18) of morulae, 24.24% (8/33) of blastocysts and 60.98% (25/41) of hatched blastocysts, respectively. The forming rate of primary ES-like cells colonies in hatched blastocyst group was significantly (p < 0.05) higher than the obtained for other groups. Two ES-like cell lines could survive to eight passages at least by using the method of mechanical dissociation, but just three passages by using the method of enzymatic dissociation. The cells formed large, multicellular colonies with distinct boundaries, exhibited many important features of ES/ES-like cells, including positive AP, SSEA-1, SSEA-3 and SSEA-4 activity. Undifferentiated buffalo ES-like cells expressed Oct-4, Nanog, Sox2 gene mRNA. In vitro differentiation experiments had demonstrated that those cells were pluripotent.

Microbial community in granules from a high-rate EGSB reactor.

The spatial distribution, quantity and diversity of different microorganisms within anaerobic granular sludge from a lab-scale expanded granular sludge bed (EGSB) reactor operated at different organic loading rates were studied using florescent in situ hybridization (FISH), real time quantitative-polymerase chain reaction (RTQ-PCR) and denaturing gradient gel electrophoresis (DGGE) techniques. The results indicated that most Eubacteria were located in the outer layer of granule, while the Archaea which mainly were methanogens and more sensible to the environmental conditions were located in the inner layer of the granule. The quantity of Archaea was obviously less than that of Eubacteria in the granules, but increased with the increasing of organic loading rates of the reactor. As the organic loading rate of the reactor increased and the operating time elapsed, the Archaea community in the granules changed significantly. Seven typical DGGE bands were collected and sequenced, and found that the dominant species of Archaea in the granules operated in the last period were mainly Methanocorpusculum, Methanobacterium, Methanosaeta.

Membrane progestin receptor beta (mPR-beta): a protein related to cumulus expansion that is involved in in vitro maturation of pig cumulus-oocyte complexes.

A new group of putative membrane receptors have now been isolated from fish and other vertebrates, including human. These proteins are classified into three groups known as membrane progestin receptor alpha, beta and gamma (mPR-alpha, -beta and -gamma). In the present study we have investigated the role of mPR-beta in regulating in vitro maturation (IVM) of pig cumulus-oocyte complexes (COCs). RT-PCR and Western blot analysis indicated that COCs contain transcripts and proteins for mPR-beta. The levels of both transcripts and proteins increased between 0 and 20h IVM, but then decreased between 20 and 44h. The luteinizing hormone (LH) and follicle-stimulating hormone (FSH) did not affect mPR-beta expression during IVM. Immunofluorescence analysis indicated that the mPR-beta was localized in the plasma membrane of cumulus cell. However, in mouse embryonic fibroblasts (MEFs), mPR-beta was detected at the endoplasmic reticulum (ER) rather than the plasma membrane. Cumulus expansion was impaired significantly (P<0.05) when COCs were incubated in maturation medium containing 10% (v/v) anti-mPR-beta serum during IVM. Bioinformatics analysis predicted that mPR-beta had an ER retention motif and an endocytosis internalization motif. These results suggest that the mPR-beta is a molecule related to cumulus expansion and it might function by regulation of exocytosis. In conclusion, this is the first description of the expression patterns and subcellular localization of mPR-beta in COCs and might shed light on the function of the protein.