Dynamics of antibiotic resistance genes and the association with bacterial community during pig manure composting with chitin and glucosamine addition.

In modern ecological systems, the overuse and misuse of antibiotics have escalated the prevalence of antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs), positioning them as emerging environmental contaminants. Notably, composting serves as a sustainable method to recycle agricultural waste into nutrient-rich fertilizer while potentially reducing ARGs and MGEs. This study conducted a 47-day composting experiment using pig manure and corn straw, supplemented with chitin and N-Acetyl-D-glucosamine, to explore the impact of these additives on the dynamics of ARGs and MGEs, and to unravel the interplay between these genetic elements and microbial communities in pig manure composting. Results showed that adding 5% chitin into composting significantly postponed thermophilic phase, yet enhanced the removal efficiency of total ARGs and MGEs by over 20% compared to the control. Additionally, the addition of N-Acetyl-D-glucosamine significantly increased the abundance of tetracycline-resistant and sulfonamide-resistant genes, as well as MGEs. High-throughput sequencing revealed that N-Acetyl-D-glucosamine enhanced bacterial α-diversity, providing diverse hosts for ARGs and MGEs. Resistance mechanisms, predominantly efflux pumps and antibiotic deactivation, played a pivotal role in shaping the resistome of composting process. Co-occurrence network analysis identified the key bacterial phyla Proteobacteria, Firmicutes, Gemmatimonadota, and Myxococcota in ARGs and MGEs transformation and dissemination. Redundancy analysis indicated that physicochemical factors, particularly the carbon-to-nitrogen ratio emerged as critical variables influencing ARGs and MGEs. The findings lay a foundation for the developing microbial regulation method to reduce the risks of ARGs in animal manure composts.

Effects of aeration modes and rates on nitrogen conversion and bacterial community in composting of dehydrated sludge and corn straw.

Aeration is an important factor to regulate composting efficiency and nitrogen loss. This study is aimed to compare the effects of different aeration modes (continuous and intermittent) and aeration rate on nitrogen conversion and bacterial community in composting from dehydrated sludge and corn straw. Results showed that the intermittent aeration mode at same aeration volume was superior to the continuous aeration mode in terms of NH3 emission reduction, nitrogen conversion and germination index (GI) improvement. Intermittent aeration mode with 1200 L/h (aeration 5 min, stop 15 min) [K5T15 (V1200)] and 300 L/h of continuous aeration helped to the conservation of nitrogen fractions and accelerate the composting process. However, it was most advantageous to use 150 L/h of continuous aeration to reduce NH3 emission and ensure the effective composting process. The aeration mode K5T15 (V1200) showed the fastest temperature rise, the longer duration of thermophilic stage and the highest GI (95%) in composting. The cumulative NH3 emission of intermittent aeration mode was higher than continuous aeration mode. The cumulative NH3 emission of V300 was 23.1% lower than that of K5T15 (V1200). The dominant phyla in dehydrated sludge and corn straw composting were Firmicutes, Proteobacteria, Actinobacteria, and Bacteroidetes. The dominant phylum in the thermophilic stage was Firmicutes (49.39%~63.13%), and the dominant genus was Thermobifida (18.62%~30.16%). The relative abundance of Firmicutes was greater in the intermittent aeration mode (63.13%) than that in the continuous aeration mode (57.62%), and Pseudomonas was dominant in composting with lower aeration rate and the lowest NH3 emission. This study suggested that adjustment to the aeration mode and rate could affect core bacteria to reduce the nitrogen loss and accelerate composting process.

Determining the extraction conditions and phytotoxicity threshold for compost maturity evaluation using the seed germination index method.

The phytotoxicity of the compost aqueous extracts determines the maturity. To improve the accuracy of compost maturity evaluation using the seed germination index (GI) method, different extraction methods (different moisture content and extraction ratio) were designed to obtain samples with various phytotoxic level. This study analyzed the effects of different extraction condition of compost samples on GI, and established the relationship between phytotoxicity and GI. The results showed that the moisture content and extraction ratio of the compost significantly affected the GI. The extraction ratio for the compost with 60-70 % moisture content was 1:10 (ratio of compost mass to extract volume). However, commercial compost, which must have a moisture content of 30-45 %, had an extraction ratio of 1:30 (w:v). More importantly, compost extraction based on dry weight, with a moisture content of 10-15 %, more effectively reflected the phytotoxicity variations during composting. In such cases, the extraction ratio should be at least 1:30 (w:v) but not exceed 1:50 (w:v). The relationship between phytotoxicity and GI showed that dissolved organic carbon and dissolved nitrogen were the most important factors influencing GI, followed by NH4+, electrical conductivity, K, volatile fatty acids, Zn, and Cu. For composts with a GI greater than 70 %, the dissolved organic carbon, dissolved nitrogen, and NH4+ concentrations were below 257, 164, and 73 mg/L, respectively. These findings provide an optimized standard method for compost maturity evaluation using GI and a concentration threshold of key phytotoxicity is proposed to achieve accurate control of compost maturity.

Bacillus licheniformis inoculation promoted humification process for kitchen waste composting: Organic components transformation and bacterial metabolic mechanism.

Kitchen waste (KW) composting always has trouble with slow humification process and low humification degree. The objective of this study was to develop potentially efficient solutions to improve the humification of KW composting, accelerate the humus synthesis and produce HS with a high polymerization degree. The impact of Bacillus licheniformis inoculation on the transformation of organic components, humus synthesis, and bacterial metabolic pathways in kitchen waste composting, was investigated. Results revealed that microbial inoculation promoted the degradation of organic constituents, especially readily degradable carbohydrates during the heating phase and lignocellulose fractions during the cooling phase. Inoculation facilitated the production and conversion of polyphenol, reducing sugar, and amino acids, leading to an increase of 20% in the content of humic acid compared to the control. High-throughput sequencing and network analysis indicated inoculation enriched the presence of Bacillus, Lactobacillus, and Streptomyces during the heating phase, while suppressing the abundance of Pseudomonas and Oceanobacillus, enhancing positive microbial interactions. PICRUSt2 analysis suggested inoculation enhanced the metabolism of carbohydrates and amino acids, promoting the polyphenol humification pathway and facilitating the formation of humus. These findings provide insights for optimizing the humification process of kitchen waste composting by microbial inoculation.

Boosting activity of γ-alumina-supported vanadium catalyst for isobutane non-oxidative dehydrogenation via pure V3.

The vanadium-based dehydrogenation (DH) catalyst is becoming a promise alternative to the industrial used Pt- and Cr-based catalysts, due to lower cost and less environmental threat. However, the low DH activity hampered the industrial application of vanadium-based catalysts. Herein, for the first time, we introduce a method to prepare high-efficiency vanadium-based catalyst by constructing pure V3+ species on γ-Al2O3 through treatment of as-prepared thiovanadate. The V3+ species contributes to not only enhancing the DH activity, but also fabricating the V3+-O/S acid-base pair with ideal strength and stability. The isobutene yield can reach as high as 56.9 wt%. Only Lewis acid is recognized on V3+/Al2O3 catalyst, while no Brønsted acid remains. The side-reactions are consequently inhibited, and the selectivity to isobutene is improved. Besides, with the increase of vanadium loadings, the Lewis acid content increases at first and then decreases, and the content of acid sites in middle strength keeps decreasing. Though the deposited coke on V3+/Al2O3 was just 2.5 wt% during 8.5 h consecutive DH reaction, the valence state of vanadium was still influenced and the fraction of inert V4+ species increased steadily. This study will improve the potential for industrial application of vanadium-based DH catalyst, and offer theoretical guidance for optimization of ideal DH catalysts.

Comparing the bacterial composition, succession and assembly patterns in plastisphere and kitchen waste composting with PLA/PBAT blends.

Biodegradable plastics has aroused increasing concern due to the negative environmental impact of plastic waste, however, the impact of biodegradable plastics mixed into kitchen waste (KW) on composting remains poorly understood, especially focusing on bacterial communities in the unique "plastisphere". Here, KW composting for 120 days with adding poly lactic acid / poly butylene adipate-co-terephthalate (PLA/PBAT) plastics were conducted to reveal the dynamics of bacterial composition, succession, and assembly process in different ecological niches (compost and plastisphere). Results showed that the existence of PLA/PBAT plastics in composting would not significantly affect the safety and maturation of composts. After composting, 80% PLA/PBAT were degraded and there were prominent divergences of bacterial compositions between plastisphere, composts with PLA/PBAT and control. Co-occurrence network suggested that PLA/PBAT plastisphere exhibited higher network complexity and cohesion than that in compost, and PLA/PBAT increased bacterial module hubs, network hubs, and connectors in composting compared to control, but might enrich pathogens. Phylogenetic bin-based null model analysis indicated that stochastic processes obviously shaped the communities on PLA/PBAT plastisphere, but compare to control, PLA/PBAT plastics enhanced the contribution of deterministic processes on composting bacterial community assembly. These findings deeply understood the assembly patterns and diversity of plastisphere and composting processes, laying down a foundation on applying biodegradable plastics under the classification of domestic garbage.

Model Emulsions Stabilized with Nonionic Surfactants: Structure and Rheology Across Catastrophic Phase Inversion.

The catastrophic phase inversion process of model emulsions (water/Span 80-Tween 80/heptane) from oil-in-water to water-in-oil emulsion was investigated. During this process, the phase inversion of the emulsion was monitored through Fourier transform infrared spectroscopy (FT-IR). In emulsions without NaCl, oil-in-water gel emulsions are formed prior to phase inversion. As the HLB value increases, the oil volume fraction required for phase inversion becomes higher. Polydisperse distribution of the gel emulsion is observed from microscope optical images. The Turbiscan Lab stability analyzer indicates that O/W gel emulsions before the phase inversion has good stability at 50 °C. Rheological measurements reveal that emulsions exhibit non-Newtonian behavior. The viscosity of the gel emulsions increases significantly prior to phase inversion. As the oil volume fraction increases, the storage modulus and loss modulus of the gel emulsion increase to a maximum, at which catastrophic phase inversion occurs. In emulsions with NaCl, there is no oil-in-water gel emulsion formed before phase inversion. The physicochemical properties of the emulsion play a crucial role in whether gel emulsions are produced during catastrophic phase inversion. These gel emulsions have the potential to diversify the applications in crude oil extraction, drug delivery systems, packaging materials, and other fields.

Effect of Fe(III) Species on the Stability of a Water-Model Oil Emulsion with an Anionic Sulfonate Surfactant as an Emulsifier.

The stability of an emulsion has an important effect on enhancing oil recovery. However, the effect of ions with different valences on the stability of the emulsion emulsified by an ionic surfactant is not fully understood. In this study, the effects of Fe(III) species on the stability, microscopic morphology of droplets, interfacial properties, and rheological properties of water-model oil emulsions emulsified by sodium dodecyl benzenesulfonate (SDBS) were explored. The effect of Fe(III) species on the stability of a W/O crude oil emulsion was also explored. The stability experiment results show that the addition of the Fe(III) species impairs the stability of the model oil-in-water (O/W) emulsion, in which the O/W model oil emulsion is inverted to a water-in-model oil (W/O) emulsion at ∼99 ppm. With the increase of Fe(III) species concentration, stable W/O model oil and W/O crude oil emulsions are obtained. The rheological results indicated that the existence of the Fe(III) species has a remarkable effect on the viscosity and viscoelastic behaviors of the water-model oil emulsion. The calculation results based on Derjaguin-Landau-Verwey-Overbeek (DLVO) theory are in accord with the stability experiment results. Furthermore, the addition of EO groups makes the phase inversion point appear at a higher Fe(III) species concentration, forming a more stable W/O model oil emulsion and a more unstable O/W model oil emulsion. The experimental results are helpful to comprehensively understand the effect of Fe(III) species on the stability of an emulsion emulsified by an anionic sulfonate surfactant, which can help to enhance the oil recovery.

Effect of Temperature on Asphaltene Precipitation in Crude Oils from Xinjiang Oilfield.

During the production of crude oil, asphaltenes are prone to precipitate due to the changes of external conditions (temperature, pressure, etc.). Therefore, a series of research studies were designed to investigate the effect of temperature on asphaltene precipitation for two Xinjiang crude oils (S1, S2) so as to reveal the mechanism of asphaltene dissolution. First, the changes of asphaltene precipitation were intuitively observed by using a microscope. The results demonstrated that the asphaltene solubility increased with the increase of temperature and the dispersion rate of asphaltene particles increased with the decrease of particle size. Second, the variation of asphaltene precipitation with temperature was quantified by a gravimetric method. The results suggested that the different asphaltenes showed different sensitivity to temperature within the temperature range 25-120 °C. Third, a hypothesis was proposed to explain these results and proved that the asphaltene aggregate structure was an important factor for asphaltene stability. The crystallite parameters of asphaltenes were obtained by X-ray diffraction (XRD) to describe the structural characteristics. The results revealed that the layer distance between aromatic sheets (d m ) of asphaltenes derived from S1 oil and S2 oil were 0.378 and 0.408 nm, respectively, which implied that the asphaltene aggregates derived from S2 oil were looser than those of S1 oil. Therefore, high temperature could facilitate the penetration of resins into asphaltene aggregates and ultimately improve the dispersion of asphaltenes. Finally, molecular dynamics (MD) simulation was used to verify the conclusions. Based on the molecular dynamics method, asphaltene aggregate models were developed. The compactness and internal energy of each model were calculated. The results showed that the asphaltene dispersion capability was proportional to the porosity and internal energy.

Molybdenum disulfide composite materials with encapsulated copper nanoparticles as hydrogen evolution catalysts.

In the current work, a series of molybdenum disulfide composite MCNTs@Cu@MoS2 materials with high hydrogen evolution performance are prepared. In the hydrogen evolution reaction, their overpotential is as low as 225 mV at a current density of 10 mA cm-2 in 1 M H2SO4 as electrolyte solution. This excellent catalytic activity has been ascribed to its lower electrical impedance and high double layer capacitance. The encapsulation of copper nanoparticles into MoS2 crystals significantly reduces their resistance, enhancing the electron transfer rate during water electrolysis. Thereby, the introduction of conductive nanoparticles into semi-conductive catalyst crystals would be an efficient measure to improve their electrochemical catalytic activity in the hydrogen evolution reaction.

Co-Catalysis for Hydroamidocarbonylation of Alkynes with Amides over a Bifunctional Ligand-Based Pd Catalyst.

The hydroamidocarbonylation of alkynes with amides allows for the synthesis of α,ß-unsaturated imides with the advantage of 100% atomic economy. Herein, the bifunctional ligand (L1) containing a sulfonic acid group (-SO3 H) and phosphino-fragment enable the Pd catalyst to accomplish the hydroamidocarbonylation of alkynes with amides. It was found that, due to an intramolecular synergetic effect, the L1-based Pd-catalyst exhibited much higher activity than the individual mechanical mixtures of Xantphos-based Pd-complex and MeSO3 H. The formation and stability of Pd-H species were promoted by the presence of L1, which was verified by in situ high-pressure FT-IR analysis. Under the optimized conditions, the target products of the branched imides were obtained with yields in the range of 46-87% over the L1-based Pd-catalyst. Advantageously, as an ionic ligand, the L1-based Pd-catalyst could be recycled for 4 runs in the ionic liquid of [Bmim]NTf2 without any obvious activity loss and detectable metal leaching.

Isobutane dehydrogenation over high-performanced sulfide V-K/γ-Al2O3 catalyst: Modulation of vanadium species and intrinsic effect of potassium.

Compared with industrial used Pt- and Cr-based catalyst in dehydrogenation (DH) of light alkanes, the sulfide V-K/γ-Al2O3 catalyst reported in this study shows lower cost and toxicity, and significant DH performance. The yield to isobutene reached as high as 52.9%, which is among the highest reported to date. We attribute such high isobutene yield to the precise modulation of polymerization degree for vanadium species via doping of potassium and indicating that the synergy between vanadium species and acid sites is critical to enhance the DH performance. Our previous work showed sulfidation promoted the increase of DH performance for vanadium-based catalyst, and we go further in this study to explore the correlation between increased range of DH performance and the added potassium. The different loaded potassium leads to variation in sulfidation degree, affecting the properties of vanadium species and acid properties consequently. The potassium was distributed uniformly on surface of the sulfide vanadium-based catalyst and was predominantly bonded with the vanadium species rather than with the γ-Al2O3 support. With increasing the potassium amount from 0 to 3 wt%, the acid amount kept decreasing, and some specific strong acid sites appeared once adequate sulfur was introduced in the V-K/γ-Al2O3 catalyst. The characterization and DFT results both revealed that the doped potassium contributes to regulating the vanadium species in the oligomeric state. The synergy between vanadium species and acid properties was regulated by the added potassium simultaneously, and thus the DH performance was enhanced. This study provides promising strategy for preparation of environment-friendly model industrial DH catalyst.

Application of iris fluorescein angiography in diabetic iridopathy and retinopathy in brown iris.

PURPOSE: This study aimed to evaluate the relationship between diabetic iridopathy (DI) and diabetic retinopathy (DR) and distinguish iris neovascular and physiological leakage using iris fluorescein angiography (IFA). METHODS: A total of 210 subjects were prospectively recruited in this study. Sixty normal subjects were divided equally into three groups (<40 years old, 40-59 years old, and 60-79 years old). One hundred fifty patients with diabetic mellitus (DM) were divided equally into five groups (no retinopathy, mild non proliferative DR (mildnPDR), moderate nPDR, severe nPDR, and PDR group). Normal subjects underwent IFA. Patients with DR underwent both IFA and ultrawide field fundus fluorescein angiography (uwFFA) at the same time. The leakage time and area were recorded and compared with each group. RESULTS: Fluorescein leakage occurred at the pupillary edge of patients that were 40-59 and 60-79 years old but not in those <40 years old. In the PDR group, the leakage time was earlier and the leakage area was larger than nPDR and patients with no retinopathy (p = 0.039 and p = 0.005, respectively). However, the leakage time and area were not significantly different between patients with no retinopathy and nPDR (p > 0.05). CONCLUSION: IFA examination can only assist in estimating the fundus severity of PDR patients, whereas the fundus changes of patients with no retinopathy and nPDR were not related to DI changes.Trial registration No.: ChiCTR1800018003.The date of registration: Aug 26th, 2018.

Effect of Phosphorus Modification on the Acidity, Nanostructure of the Active Phase, and Catalytic Performance of Residue Hydrodenitrogenation Catalysts.

A series of NiMoP(x)-Al catalysts with different phosphorus contents were prepared by the incipient wetness co-impregnation method. The effects of phosphorus modification on the acidity, active phase nanostructure, and catalytic properties of the residue hydrodenitrogenation catalysts were investigated to find the role of phosphorus in the catalytic mechanism. The results of temperature-programmed desorption of NH3 and pyridine IR spectroscopy of the catalysts indicate that phosphorus modification can increase the total acid and Brønsted acid. Transmission electron microscopy analysis shows that phosphorus modification increases the stacking number N A, reduces the slab length L A of the active MoS2 phase, and increases the Mo dispersion f Mo, leading to the promotion of the sulfidation degree of the active Mo phase and thus increasing the denitrification rate. The catalyst with a 3.4 wt % P2O5 loading shows the highest Brønsted/Lewis acid ratio, the largest amount of three-layer active phases, the smallest L A, the highest f Mo, the optimal sulfurization degree, and the highest denitrification rate, 63.6%, indicating the correlation between the nanostructure of the active phase and its catalytic property because of the addition of phosphorus.

The effect of hemodialysis on ocular changes in patients with the end-stage renal disease.

Background: Numerous metabolic parameters can be changed during hemodialysis in the end-stage renal disease (ESRD) caused by systemic diseases, such as diabetes mellitus, hypertension. Some ocular parameters also can be variable due to the changes after hemodialysis. This study evaluates the effects of ocular parameters, including best-corrected visual acuity (BCVA), intraocular pressure (IOP), central macular thickness (CMT), subfoveal choroidal thickness (SFCT), retinal arteriolar caliber (RAC), retinal venular calibre (RVC), in ESRD patients following hemodialysis. Materials and methods: Two-hundred and two ESRD patients were recruited resulting in 404 eyes evaluations. All patients underwent hemodialysis in the Dialysis Unit of the Second Hospital of Tianjin Medical University. BCVA, CMT, IOP, SFCT, RAC and RVC were evaluated before and after hemodialysis. Systemic parameters were collected such as age, body weight, systolic blood pressure (SBP), diastolic blood pressure (DBP), duration of hemodialysis, body weight changes, high density lipoprotein cholesterol (HDLC), low density lipoprotein cholesterol (LDLC), very low density lipoprotein cholesterol (VLDLC), glycosylated hemoglobin (HbA1c). Results: The causes of ESRD patients included chronic glomerulonephritis (n = 65), diabetes mellitus (n = 60), hypertensive nephrosclerosis (n = 37), and other causes (n = 40). In our study, BCVA (p = .817), CMT (p = .252) and IOP (p = .978) did not significantly change after hemodialysis. SFCT significantly decreased from 254.29 ± 69.36 µm to 235.54 ± 659.90 µm (p = .002) following hemodialysis. SFCT changes were significantly correlated with SBP (p = .042) and body weight changes (p = .044). The RAC and RVC were dilated significantly (p = .033, p = .007). RVC changes were correlated with baseline DBP (p = .003), HDLC (p = .009), LDLC (p = .004) and changes in DBP (p = .037) and body weight (p = .001). Conclusion: Hemodialysis can affect various ocular parameters including SFCT, RAC and RVC, which changed significantly following hemodialysis. Whereas BCVA, IOP and CMT did not change after hemodialysis in ESRD patients. The systemic compensatory mechanisms of the changes in SBP, DBP, body weight following hemodialysis need further study.

The efficacy of conbercept or ranibizumab intravitreal injection combined with laser therapy for Coats' disease.

PURPOSE: The current treatment approaches for Coats' disease by intravitreal injection of anti-vascular endothelial growth factor (VEGF) agents (ranibizumab or conbercept) combined with laser therapy were evaluated for the efficacy during the treatment. METHODS: The medical records of 28 patients diagnosed with Coats' disease followed by the treatment with intravitreal injection of anti-VEGF agents and laser therapies at Tianjin Medical University Eye Hospital and Hebei Eye Hospital during July 2012 and October 2017 were reviewed retrospectively. Clinical outcomes were recorded with a minimum follow-up of 6 months. The patients were divided into ranibizumab- and conbercept-treated groups, as well as based on age: pediatric and adult groups. RESULT: Twenty-eight patients were involved in this study. The average number of the injections was 2.82 ± 0.98. Laser photocoagulation was conducted in all patients, and the average number of lasers was 2.63 ± 0.74. The average follow-up period was 24.29 ± 9.85 months. Fourteen patients (50%) were stable, 12 (43%) patients were improved, and 2 patients (7%) showed recurred subretinal fluid and exudation. The final best corrected visual acuity (BCVA) increased markedly after intravitreal injection of ranibizumab or conbercept combined with laser therapy (p = 0.029, p = 0.009, respectively). The number of injections and lasers between conbercept and ranibizumab groups did not vary significantly (p = 0.160, p = 0.573, respectively). Nine patients (60%) in the ranibizumab-treated group and five (38%) in the conbercept-treated group reached a stable phase, and five (33%) and seven (54%) patients got the vision improved after treated with ranibizumab or conbercept, respectively. In pediatric and adult groups, the initial and final BCVA differed significantly (p = 0.03, p = 0.008, respectively). However, the injection number was remarkably different (p = 0.02), while the laser numbers did not have any markedly difference (p = 0.38). CONCLUSION: Intravitreal injection of ranibizumab or conbercept combined with laser therapy is an effective therapeutic option in Coats' disease. Moreover, the intravitreal injection of ranibizumab or conbercept had no significant adverse effects and appeared to offer visual improvement in Coats' disease.

Study on Colloidal Model of Petroleum Residues through the Attraction Potential between Colloids.

The samples of DaGang atmospheric residue (DG-AR), Middle East atmospheric residue (ME-AR), TaHe atmospheric residue (TH-AR), and their thermal reaction samples were chosen for study. All the samples were fractioned into six components separately, including saturates plus light aromatics, heavy aromatics, light resins, middle resins, heavy resins, and asphaltenes. The dielectric permittivity of the solutions of these components was measured, and the dielectric permittivity values of the components can be determined by extrapolation, which increased steadily from saturates plus light aromatics to asphaltenes. Moreover, the Hamaker constants of the components were calculated from their dielectric permittivity values. The Van der Waals attractive potential energy between colloids corresponding to various models could be calculated from the fractional composition and the Hamaker constants of every component. It was assumed that the cores of colloidal particles were formed by asphaltenes and heavy resins mainly; the other fractions acted as dispersion medium. For the three serials of thermal reaction samples, the Van der Waals attraction potential energy between colloids for this kind of model was calculated. For TH-AR thermal reaction samples, the Van der Waals attraction potential energy presented the maximum as thermal reaction is going on, which was near to the end of coke induction period.

A newly-designed positioning system for simultaneous indocyanine green and fluorescein anterior segment angiography of the albino rabbit.

BACKGROUND: Simultaneous recording of vertical iris indocyanine green angiography (ICGA) and iris fluorescein sodium angiography (IFA) in albino rabbits. MATERIAL/METHODS: An easily adjusted control system was designed to position the CSLO scanning lens perpendicular to the surface of the iris. Twelve albino rabbits were randomly divided into 2 groups. Using 5 mg fluorescein sodium and 5 mg indocyanine green, iris angiograms (IA) of 6 albino rabbits were performed with application of the positioning system in Group A, and no positioning system in Group B. The time spending on vertical eye position and the effects of simultaneous IA were observed. RESULTS: With the use of the positioning system, the irises of rabbits quickly achieved the vertical site, averaging 37.50+/-8.17 s in Group A, and 408.33+/-58.79 s in Group B. The difference was statistically significant, and the time saved averaged 370.83 s. Compared with the other methods of single-dye angiography, simultaneous digital angiography provided 2 kinds of full, dynamic videos of iris vessels in all albino rabbits. The emergence time of IFA and ICGA was 5-9 s, with an average time for ICGA of 6.4 s, and for IFA of 6.5 s. Except for leakage, the simultaneous ICGA and IFA appearance of this vascular pattern was the same as the single IFA described previously. CONCLUSIONS: Simultaneous vertical IA with indocyanine green and fluorescein sodium is a potentially powerful technique that allows high-quality fluorescence imaging of the albino rabbit iris.

[Effects of microbial inoculation on composting in a bioreactor].

A composting experiment with chicken manure was carried out in a lab-scaled bioreactor to study the effects of microbial inoculation (a single Bacillus megaterium and a compound VT agent) on the changes of the temperature, oxygen concentration, C/N ratio, WSC (water-soluble carbon), germination index (GI), and cellulase and dehydrogenase activity. The results showed that the use of compound VT agent was more effective in the growing of starting temperature and maintaining of the high-temperature during composting than the single Bacillus megaterium treatment. The oxygen concentration in the composting with inoculation (both Bacillus megaterium and VT) was lower than that of the composting without inoculation. Meanwhile, the inoculation with compound microbial inocula (VT) showed lower of C/N ratio, higher WSC concentration and higher GI in the compost than that of the individual microbial inoculation. Furtherly, microbial inoculation could increase the cellulase activity and dehydrogenase activity in the composting process and promote the decomposition of cellulose during the composting.

[Application of confocal scanning laser Doppler retinal flowmetry in the measurement of fundus blood flow parameters after retinal detachment surgery].

OBJECTIVE: To discuss the influence of retinal detachment (RD) surgery on the blood flow of retina and optic nerve head. METHODS: Heidelberg Retina Flowmeter (HRF) was used to measure the blood flow of retina and optic nerve head in 62 eyes of 62 patients with postoperative rhegmatogenous RD surgery, including 34 eyes having undertaken vitreoretinal (VR) surgery and 28 eyes, scleral buckling (SB) surgery. Operative methods included scleral encircling procedure, cryotherapy, lensectomy, vitrectomy, perfluorodeclin liquid application, endolaser and C(2)F(6) gas or silicone oil tamponade. RESULTS: The blood flow volume (VOL), blood flow velocity (FLW) and the erythrocyte flow velocity (VEL) of fundus in the postoperative RD eyes were reduced in the comparison with those of the fellow control eyes. The VEL of temporal and nasal papillary disk rim had significant differences (P < 0.05). The VOL, FLW and VEL of the papillary vessel, VOL and FLW of temporal and nasal papillary disk rim, VOL of temporal and nasal juxtapapillary retina in the operative eyes were lower than those of the fellow eyes (P < 0.01). In the comparison between the eyes having undertaken VR surgery and the eyes undertaken SB surgery, the VOL, FLW and VEL of VR surgery were reduced more than those of SB surgery. The VEL of temporal and nasal papillary disk rim and nasal juxtapapillary retina and FLW of temporal juxtapapillary retina had significant differences (P < 0.05). VOL, FLW and VEL of silicone oil tamponade eyes were reduced more than those in the operative eyes without silicone oil tamponade. VOL of nasal papillary disk rim and juxtapapillary retina had significant differences (P < 0.05). VOL and VEL of temporal papillary disk rim, VOL of temporal juxtapapillary retina had very significant differences (P < 0.01). CONCLUSIONS: VR surgery and SB surgery of RD influence papillary and retinal VOL, FLW, VEL. The influence of VR surgery on the fundus blood flow is more significant than that of SB surgery. The silicone oil tamponade also influences the VOL and VEL of the fundus.