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1.
Phys Chem Chem Phys ; 26(9): 7738-7746, 2024 Feb 28.
Article in English | MEDLINE | ID: mdl-38372654

ABSTRACT

The simplified local density (SLD) model has been frequently utilized to describe gas adsorption in porous media. The common assumptions associated with the SLD model are the graphene slit and uniform distribution of atoms. However, these fail to depict the heterogeneous surface of minerals. In this study, the original SLD model was modified by substituting mineral crystal structures for the homogeneous carbon layer when building the slit. The modified model may capture the heterogeneity-induced variation of the fluid-pore interaction potential and adsorbed phase density near the mineral surface. The calculated adsorption isotherms of methane and carbon dioxide on illite and calcite surfaces at 330.15 K were compared with literature experiment data to validate the modified SLD model. For the simulation of gas adsorption isotherms, the modified model predictions agree reasonably well with the previously reported experiment results using the gravimetric method. The calculated density profile in the slit indicates the monolayer adsorption behavior of CH4 and CO2. Based on more precise interaction potentials, the number of regression parameters was reduced to two, and the physical meaning of the model parameters was clarified. Therefore, for estimating hydrocarbon storage in reservoirs, the modified SLD model could be used as an efficient alternative to time-consuming molecular simulation methods.

2.
Chemosphere ; 352: 141297, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38296211

ABSTRACT

The ubiquitous contamination of surfactants in wastewater has raised global concerns. Photocatalysis is deemed as a promising yet challenging approach for the decomposition of surfactant residues. Herein, a novel Z-scheme heterojunction of Bi4O5Br2/Bi2S3 with covalent S-O bonds was prepared via a facile one-pot hydrothermal and subsequent annealing process. The prepared optimal Bi4O5Br2/Bi2S3 composite exhibited remarkable photo-degradation activity towards the sodium dodecylbenzene sulfonate (SDBS). The Z-scheme reaction mechanism was proposed and validated by meticulous analysis of quenching tests, ESR spectroscopy and DFT calculations. Furthermore, the presence of chemical S-O linkages between Bi4O5Br2 and Bi2S3 was identified via FT-IR and XPS analyses, which served as a distinct bridge to modify the Z-scheme route for carrier transport. The Z-scheme heterostructure, in conjunction with chemical S-O bonds, synergistically enhanced the separation rate of electron-hole pairs and thus greatly boosted the photocatalytic activity. Additionally, the possible degradation pathways of SDBS were proposed by using HR-MS technology. Moreover, real hotel laundry wastewater could be efficiently disposed by the photocatalysis of the Bi4O5Br2/Bi2S3 with a decrease in the COD value from 428 to 74 mg/L, indicating that the fabricated Z-scheme heterojunction hold great promise for effectively removing refractory surfactant contaminants from aquatic environment.


Subject(s)
Benzenesulfonates , Pulmonary Surfactants , Wastewater , Spectroscopy, Fourier Transform Infrared , Surface-Active Agents
3.
Zhen Ci Yan Jiu ; 48(12): 1266-1273, 2023 Dec 25.
Article in English, Chinese | MEDLINE | ID: mdl-38146250

ABSTRACT

OBJECTIVES: To compare the effects of 2 Hz continuous wave and 2 Hz/100 Hz dilatational wave setting in electroacupuncture(EA) on ovulation frequency, hormone levels, body fat parameters, quality of life and depression-anxiety level in polycystic ovary syndrome (PCOS) patients with abdominal obesity. METHODS: PCOS patients with abdominal obesity were randomly divided into low-frequency group (n=29) and dilatational wave group (n=29). Patients in both groups were treated with "Tongtiaodaimai" (regulating Dai Meridian) acupuncture therapy, and EA was applied to bilateral Daimai (GB26), Tianshu (ST25), Shenshu (BL23) and Ciliao (BL32). The low-frequency group received EA using a continuous wave at a frequency of 2 Hz, while the dilatational wave group received dilatational wave at a frequency of 2 Hz/100 Hz. Both groups received treatment for 30 min each time, 3 times per week for 12 consecutive weeks. Ovulation frequency was calculated according to the ovulation cycle. The contents of serum anti-Mullerian hormone (AMH) and sex hormone binding globulin (SHBG) were detected with electrochemiluminescence method. Body weight (BW) and waist circumference (WC) were measured, and body mass index (BMI) and waist-height ratio (WHtR) were calculated. PCOS questionnaire (Chi-PCOSQ), self-rating anxiety scale (SAS) and self-rating depression scale (SDS) were evaluated. RESULTS: Compared with before treatment, both the low-frequency group and the dilatational wave group showed an increase in ovulation frequency (P<0.01, P<0.05), and a decrease in BW, BMI, WC, WHtR, and SDS score (P<0.01, P<0.05);the dilatational wave group showed decreased serum AMH contents (P<0.05) and increased serum SHBG contents (P<0.05), the scores related to acne, fatigue, and dysmenorrhea in the Chi-PCOSQ increased (P<0.01, P<0.05). Compared with the low-frequency group, the dilatational wave group showed a reduction (P<0.05) in WC after treatment. CONCLUSIONS: 2 Hz/100 Hz dilatational wave EA is equally effective as 2 Hz low-frequency EA in improving ovulation frequency. In terms of reducing WC in abdominal obesity type PCOS patients, 2 Hz/100 Hz dilatational wave EA is superior to 2 Hz low-frequency EA. 2 Hz/100 Hz dilatational wave EA can decrease serum AMH, increase serum SHBG, and improve symptoms of acne, fatigue, and dysmenorrhea.


Subject(s)
Acne Vulgaris , Electroacupuncture , Polycystic Ovary Syndrome , Female , Humans , Obesity, Abdominal/therapy , Quality of Life , Polycystic Ovary Syndrome/therapy , Dysmenorrhea , Acupuncture Points , Obesity/therapy
4.
RSC Adv ; 13(12): 8227-8237, 2023 Mar 08.
Article in English | MEDLINE | ID: mdl-36922941

ABSTRACT

Reducing the recombination rate of photoexcited electron-hole pairs is always a great challenging work for the photocatalytic technique. In response to this issue, herein, a novel Z-scheme CuInS2/In2O3 with interfacial S-O linkages was synthesized by a hydrothermal and subsequently annealing method. The Fourier transform infrared (FT-IR) and X-ray photoelectron spectrometer (XPS) measurements confirmed the formation of covalent S-O bonds between CuInS2 and In2O3. The quenching and electron spin resonance (ESR) tests revealed the Z-scheme transfer route of photogenerated carriers over the CuInS2/In2O3 heterojunctions, which was further verified theoretically via density functional theory (DFT) calculations. As expected, the CuInS2/In2O3 heterojunctions showed significantly boosted photocatalytic activities for lomefloxacin degradation and Cr(vi) reduction under visible light illumination compared with the bare materials. Accordingly, a synergistic photocatalytic mechanism of Z-scheme heterostructures and interfacial S-O bonding was proposed, in which the S-O linkage could act as a specific bridge to modify the Z-scheme manner for accelerating the interfacial charge transmission. Furthermore, the CuInS2/In2O3 heterojunction also exhibited excellent performance perceived in the stability and reusability tests. This work provides a new approach for designing and fabricating novel Z-scheme heterostructures with a high-efficiency charge transfer route.

5.
Small ; 19(18): e2207370, 2023 May.
Article in English | MEDLINE | ID: mdl-36765447

ABSTRACT

Water pollution caused by the massive use of medicines has caused significant environmental problems. This work first reports the synthesis and characterization of the Cu7 S4 /CuCo2 O4 (CS/CCO) yolk-shell microspheres via hydrothermal and annealing methods, and then investigates their photocatalytic performance in removing organic water pollutants. The 10-CS/CCO composite with yolk-shell microspheres exhibits the highest photodegradation rate of carbamazepine (CBZ), reaching 96.3% within 2 h. The 10-CS/CCO also demonstrates more than two times higher photodegradation rates than the pure (Cu7 S4 ) CS and (CuCo2 O4 ) CCO. This outstanding photocatalytic performance can be attributed to the unique yolk-shell structure and the Z-scheme charge transfer pathway, reducing multiple reflections of the acting light. These factors enhance the light absorption efficiency and efficiently transfer photoexcited charge carriers. In-depth, photocatalytic degradation pathways of CBZ are systematically evaluated via the identification of degradation intermediates with Fukui index calculation. The insights gained from this work can serve as a guideline for developing low-cost and efficient Z-scheme photocatalyst composites with the yolk-shell structure.

6.
J Environ Manage ; 330: 117168, 2023 Mar 15.
Article in English | MEDLINE | ID: mdl-36603258

ABSTRACT

A novel particle combined electrode named TiO2/g-C3N4@AC (TGCN-AC) was prepared by loading TiO2 and g-C3N4 on activated carbon through gel method, which was used to degrade levofloxacin (LEF) in pharmaceutical wastewater by photoelectric process. The remarkable physicochemical features of particle electrodes were verified by using diverse characterization techniques including SEM-EDS, XRD, FT-IR, BET and pHZPC. EIS-CV and photocurrent showed excellent electrocatalysis and photoelectrocatalysis performance of particle electrodes. The photocatalytic characteristics and fluorescence properties of the particle electrode were proved by UV-vis DRS and PL spectra measurements. Combined with Tauc's plot and Mott-Schottky plots curves, the ECB and EVB of particle electrodes were determined. The experiments on different influence factors such as pH, ultrasonic, aeration, current density and the concentration of LEF were carried out in the photoelectric reactor. Under the conditions of pH values 3.0, 200 W ultrasonic, 8 L/min aeration, the mass ratio of g-C3N4 and TiO2 is 8%, after 4.0 h of photoelectric process, about 94.76% of LEF (20 mg/L) in water was degraded. TGCN-AC also has excellent reusability. The degradation rate of LEF can still reach 71.17% after repeated use for 6 times. Scavenger studies showed that h+ and O2- were the main active species. By observing the colony size of E. coli, it was proved that the LEF in the effluent had no antibacterial activity. The degradation pathways of LEF was analyzed and drawn by HPLC-MS spectra.


Subject(s)
Levofloxacin , Wastewater , Levofloxacin/chemistry , Spectroscopy, Fourier Transform Infrared , Escherichia coli , Ultrasonics , Electrodes
7.
Nucleic Acids Res ; 51(4): 1707-1723, 2023 02 28.
Article in English | MEDLINE | ID: mdl-36715325

ABSTRACT

Cell cycle regulation is of paramount importance for all forms of life. Here, we report that a conserved and essential cell cycle-specific transcription factor (designated as aCcr1) and its viral homologs control cell division in Sulfolobales. We show that the transcription level of accr1 reaches peak during active cell division (D-phase) subsequent to the expression of CdvA, an archaea-specific cell division protein. Cells over-expressing the 58-aa-long RHH (ribbon-helix-helix) family cellular transcription factor as well as the homologs encoded by large spindle-shaped viruses Acidianus two-tailed virus (ATV) and Sulfolobus monocaudavirus 3 (SMV3) display significant growth retardation and cell division failure, manifesting as enlarged cells with multiple chromosomes. aCcr1 over-expression results in downregulation of 17 genes (>4-fold), including cdvA. A conserved motif, aCcr1-box, located between the TATA-binding box and the translation initiation site of 13 out of the 17 highly repressed genes, is critical for aCcr1 binding. The aCcr1-box is present in the promoters and 5' UTRs of cdvA genes across Sulfolobales, suggesting that aCcr1-mediated cdvA repression is an evolutionarily conserved mechanism by which archaeal cells dictate cytokinesis progression, whereas their viruses take advantage of this mechanism to manipulate the host cell cycle.


Subject(s)
Sulfolobus , Transcription Factors , Transcription Factors/genetics , Archaea , Cell Division , Sulfolobus/genetics , Gene Expression Regulation
8.
Journal of Preventive Medicine ; (12): 737-740, 2023.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-987044

ABSTRACT

Objective@#To investigate the epidemiological characteristics of hepatitis A and hepatitis E in Jiaxing City, Zhejiang Province from 2005 to 2021, so as to provide insights into prevention and control of hepatitis A and hepatitis E.@*Methods@#Data of hepatitis A and hepatitis E reported in Jiaxing City from 2005 to 2021 were collected from the Chinese Disease Prevention and Control Information System. The temporal, spatial and population distribution of hepatitis A and hepatitis E were analyzed using a descriptive epidemiological method, and the trends in incidence of hepatitis A and hepatitis E were evaluated using annual percent change (APC). @*Results@# Totally 1 830 hepatitis A cases were reported in Jiaxing City from 2005 to 2021, with an annual average incidence of 2.44/105, and 2 deaths were reported, with a fatality rate of 0.11%. The incidence of hepatitis A appeared a tendency towards a decline from 2005 to 2012 (APC=-37.807%, P<0.05) and was relatively stable from 2012 to 2021 (APC=-1.277%, P>0.05), and the incidence peaked from July to September, with a monthly average incidence of 0.30/105. Higher annual average incidence of hepatitis A was seen in urban areas than in rural areas (3.91/105 vs. 1.92/105; P<0.05), among people at ages of 30 to 39 years (4.19/105), and among men than among women (3.00/105 vs. 1.93/105; P<0.05). Farmers were the predominant occupation (759 cases, 41.31%). Totally 2 176 hepatitis E cases were reported in Jiaxing City from 2005 to 2021, with an annual average incidence of 2.91/105, and 7 deaths were reported, with a fatality rate of 0.32%. The incidence of hepatitis E was relatively stable from 2005 to 2011 (APC=3.421%, P>0.05) and appeared a tendency towards a decline from 2011 to 2021 (APC=-4.294%, P<0.05), and the incidence peaked from January to March, with a monthly average incidence of 0.38/105. Higher annual average incidence of hepatitis E was seen in urban areas than in rural areas (3.50/105 vs. 2.70/105; P<0.05), among people at ages of 70 to 79 years (6.20/105), and among men than among women (3.74/105 vs. 2.05/105; P<0.05). Farmers were the predominant occupation (1 079 cases, 49.59%).@*Conclusions@#The incidence of hepatitis A and hepatitis E appeared a tendency towards a decline in Jiaxing City from 2005 to 2021. The incidence of hepatitis A was high in summer, and cases were mainly males, young and middle-aged people and farmers. The incidence of hepatitis E was high in winter, and cases were mainly males, elderly people and farmers.

9.
Journal of Preventive Medicine ; (12): 705-709, 2023.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-980344

ABSTRACT

Objective@#To investigate the resistance of Mycobacterium tuberculosis to first-line anti-tuberculosis drugs in Jiaxing City, Zhejiang Province from 2017 to 2019, so as to provide insights into improvements of the therapeutic effect of pulmonary tuberculosis. @*Methods@#Data pertaining to pulmonary tuberculosis in Jiaxing City from 2017 to 2019 were collected from the Tuberculosis Surveillance System of Chinese Disease Prevention and Control Information System, including demographics, treatment classification, sputum culture and drug resistance. The spectrum, types and prevalence of drug resistance in M. tuberculosis to four first-line tuberculosis drugs, including isoniazid (INH), rifampicin (RFP), streptomycin (SM) and ethambutol (EMB), was analyzed using a descriptive epidemiological method.@*Results@#A total of 1 310 M. tuberculosis isolates were cultured from pulmonary tuberculosis patients in Jiaxing City from 2017 to 2019, and there were 259 M. tuberculosis isolates that were resistant to anti-tuberculosis drugs, with an overall drug resistance rate of 19.77%. The prevalence rates of drug resistance to INH, SM, RFP and EMB were 13.36%, 11.83%, 5.50% and 3.59%, respectively. The prevalence of drug resistance was lower in M. tuberculosis isolates from treatment-naïve patients than from retreated patients (18.45% vs. 34.58%, P<0.05). M. tuberculosis isolates presented high resistance to SM (4.50%) and INH alone (4.35%), the highest resistance to INH-SM combinations (3.28%), and the highest resistance to INH+RFP+SM combinations (1.83%). Sixteen isolates were resistant to all the four drugs, with a drug resistance rate of 1.22%. The proportions of resistance to a single drug, RFP resistance, multidrug resistance and resistance to two and more drugs were 10.31%, 5.50%, 4.73% and 4.73%, respectively. In addition, the prevalence of RFP resistance among all patients and treatment-naïve patients both showed a tendency towards a rise from 2017 to 2019 (P<0.05). The prevalence of RFP resistance (7.01% vs. 3.76%) and resistance to two and more drugs (6.01% vs. 3.25%) was both higher among interprovincial mobile tuberculosis patients than among local non-mobile patients (P<0.05). @*Conclusions@#The overall prevalence of drug resistance was lower in M. tuberculosis isolates in Jiaxing City from 2017 to 2019 than in Zhejiang Province, with INH and RFP resistance as predominant types.

10.
Journal of Preventive Medicine ; (12): 316-319, 2023.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-971791

ABSTRACT

Objective@#To perform an epidemiological survey of the first case with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in Pinghu City of Jiaxing City, Zhejiang Province on March 13, 2022, so as to provide insights into the management of coronavirus disease (COVID-19) epidemics. @*Methods@#According to the requirements of the Protocol on Prevention and Control of COVID-19 (8th Edition), epidemiological investigations were performed among 39 cases with SARS-CoV-2 infections in Pinghu City from March 13 to 20, 2022. Cases' demographics, clinical symptoms, history of immunization and exposure were collected, and close contacts were identified. Pharyngeal swabs were sampled from infected cases for detection of SARS-CoV-2 nucleic acid and whole-genome sequencing, and the source of infection and transmission route were investigated. @*Results@#The index case for this COVID-19 epidemic was an imported case from Shanghai Municipality, who infected 6 persons via aerosol transmission when playing in the badminton venue of Pinghu National Fitness Center on March 9; subsequently, one of these infected cases infected another 18 persons when playing in the badminton venue of Jiadian Village Resident's Fitness Center in Zhapu Township on March 12. Sixteen confirmed cases were reported, and all cases were mild; another 23 asymptomatic cases were diagnosed, with no death reported. This epidemic occurred from March 11 to 20, with 3 generations of spread and a median incubation period of 3 days. The SARS-CoV-2 infected cases had a median age of 33.5 (interquartile range, 12.0) years and included 36 cases with a history of COVID-19 vaccination. There were 16 cases with fever, cough, runny nose and sore throat, and 13 cases with imaging features of pneumonia. The effective reproductive number (Rt) of the COVID-19 epidemic was 7.73 at early stage, and was less than 1 since March 21. Whole-genome sequencing identified Omicron BA.2 variant among 33 cases, which had high homology with the index cases. @*Conclusion@#This epidemic was a cluster of COVID-19 caused by imported Omicron BA.2 variant infection from Shanghai Municipality, and the COVID-19 transmission was mainly caused by indoor aerosols.

11.
Cell Transplant ; 31: 9636897221086971, 2022.
Article in English | MEDLINE | ID: mdl-35416078

ABSTRACT

Between the completion of the mesenchymal stem cell (MSCs) preparation and the transplantation into the patient, there is a time interval during which the quality control and transport of MSC products occur, which usually involves suspending the cells in normal saline in an oxygen-glucose deprivation (OGD) microenvironments. Thus, how to effectively maintain MSC viability during the abovementioned time interval is bound to play a significant role in the therapeutic effect of MSC-based therapies. Recently, menstrual blood-derived endometrial stem cells (MenSCs) have attracted extensive attention in regenerative medicine due to their superior biological characteristics, including noninvasive protocols for their collection, abundant source material, stable donation, and autotransplantation. Therefore, this study aimed to mainly determine the effect of storage temperature on the maintenance of MenSC viabilities in an OGD microenvironment, and to preliminarily explore its potential mechanism. Simultaneously, the effects of solvents commonly used in the clinic on MenSC viability were also examined to support the clinical application of MenSCs. Consequently, our results demonstrated that in the OGD microenvironment, a nonfreezing low temperature (4°C) was suitable and cost-effective for MenSC storage, and the maintenance of MenSC viability stored at 4°C was partly contributed by the sustained releases of autophagy-produced energy. Furthermore, the addition of human serum albumin effectively inhibited the cell sedimentations in the MenSC suspension. These results provide support and practical experience for the extensive application of MenSCs in the clinic.


Subject(s)
Glucose , Mesenchymal Stem Cells , Autophagy , Delayed-Action Preparations , Female , Humans , Menstruation , Oxygen/pharmacology , Temperature
12.
Reprod Toxicol ; 110: 39-48, 2022 06.
Article in English | MEDLINE | ID: mdl-35346788

ABSTRACT

Although the cancer incidence showed a yearly increasing trend, the long-term survival rate of cancer patients significantly increased with the continuous improvements in cancer diagnosis and treatment. Therefore, recent strategies for cancer treatment not only focus on improving the survival rate of patients but also simultaneously consider the life quality of cancer patients, especially for those with fertility requirements. Stem cell-based therapies have exhibited promising improvement in various disease treatments, and provide hope for diseases without effective treatment. Menstrual blood-derived endometrial stem cells (MenSCs) can be noninvasively and periodically obtained from discarded menstrual blood samples and exhibit high proliferative capacity, low immunogenicity and autologous transplantation. As expected, MenSCs treatment effectively improved the viability of cisplatin-injured ovarian granulosa cells (GCs) and significantly upregulated their antiapoptotic capacity. Further results demonstrated that MenSCs treatment significantly upregulated autophagy activity in cisplatin-injured ovarian GCs, and the degree of autophagy activation was positively correlated with the viability improvement of ovarian GCs, while autophagy inhibitors significantly impaired MenSC-promoted viability improvement of cisplatin-injured ovarian GCs. Additionally, MenSCs treatment can also significantly promote the proliferation of normal GCs by activating the PI3K/Akt signaling pathway. Conclusively, MenSCs treatment not only enhanced the antiapoptotic capacity and survival of cisplatin-injured ovarian GCs by upregulating autophagy activity but also improved the viability of normal ovarian GCs by activating the PI3K/Akt signal pathway. These results provide a theoretical and experimental foundation for the clinical application of MenSCs in improving chemotherapy-induced ovarian injury and delaying ovarian senescence.


Subject(s)
Cisplatin , Proto-Oncogene Proteins c-akt , Autophagy , Cisplatin/toxicity , Female , Granulosa Cells , Humans , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Stem Cells
13.
Front Microbiol ; 11: 1211, 2020.
Article in English | MEDLINE | ID: mdl-32733390

ABSTRACT

Application of probiotics in the food industry has been hampered by their sensitivity to challenging conditions that reduce their vitality in food matrices. A lot of attempts have been made to promote the growth of these probiotics in the aspect of nutrition demands. Among the other adverse conditions, oxygen stress can restrict the growth of probiotics and has not yet been paid enough attention to. In this study, the effect of a petunidin-based anthocyanin (ACN) on the growth of probiotic Lactobacillus plantarum ST-III was investigated under oxygen stress. The growth of ST-III was analyzed through spot assay on agar plates as well as plating-based enumeration of the viable cells in the liquid culture. Results indicated that ACN could efficiently improve the growth of ST-III under oxygen stress, whereas no effect was observed in the absence of oxygen stress. Further investigations indicated that ACN reduced the oxido-reduction potential of the culture; meanwhile, it exerted a positive transcriptional regulation on the thioredoxin system of ST-III, leading to a decrease in reactive oxygen species accumulation within the cells. Moreover, ACN enabled the growth of ST-III in reconstituted skim milk and promoted the formation of milk clots. These results revealed the role of a petunidin-based ACN in oxygen stress relief and highlighted its potential in manufacture and preservation of L. plantarum-based dairy products.

14.
Open Forum Infect Dis ; 7(6): ofaa231, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32613025

ABSTRACT

BACKGROUND: Severe acute respiratory syndrome coronavirus 2, the pathogen causing novel coronavirus disease of 2019 (COVID-19), efficiently spreads from person to person in close contact settings. Transmission among casual contacts in settings such as during social gatherings is not well understood. METHODS: We report several transmission events to both close and casual contacts from a cluster of 7 COVID-19 cases occurring from mid-January to early February 2020. A total of 539 social and family contacts of the index patient's, including members of a 2-day wedding and a family party, were contacted and screened through epidemiologic surveys. The clinical progression of all cases is described. RESULTS: We estimate the secondary attack rate among close contacts to be 29% (2 of 7) and for the casual contacts to be 0.6% (3 of 473). The incubation period of our case cluster was 4-12 days (median, 7 days). CONCLUSIONS: Transmission efficiency among close contacts was higher than among casual contacts; however, transmission from second-generation cases may help spread the virus during the incubation period.

15.
J Sci Food Agric ; 100(14): 5276-5282, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32530047

ABSTRACT

BACKGROUND: Sterilization of milk is aimed at killing the microorganisms present. There are three main sterilization methods commonly used in milk processing: high temperature and short time (HTST) pasteurization, ultrahigh pasteurization (UP), and ultrahigh temperature (UHT) sterilization. The Maillard reaction is of special interest in studying the effect of heat treatment on milk quality. Furfural compounds are one of the typical intermediates of the Maillard reaction, which have safety risks related to mutagenic and genotoxic effects. The furfural compounds content is directly related to the heat treatment intensity. RESULTS: The furfural compounds content was measured using high-performance liquid chromatography with ultraviolet detection in 12 min. Then, 13 levels of heat treatment intensity (combinations of temperature and time) and three levels of homogenization pressure were selected to study the change of the furfural compounds content after different processing technologies in a pilot plant. The results show a higher temperature treatment can stimulate more Maillard reaction intermediates, such as hydroxymethylfurfural and furfural. A temperature regression evaluation model and content prediction models of hydroxymethylfurfural and furfural were developed to quantify the relationship between the furfural content and heat treatment with the data from the pilot plant. CONCLUSION: Based on the temperature evaluation model, the heating temperature of three milk products was evaluated. The homogenization pressures had little effect on the furfural content in liquid milk. The emergence of the furyl methyl ketone and methylfurfural can be detected after overprocessing of the liquid milk. © 2020 Society of Chemical Industry.


Subject(s)
Furaldehyde/chemistry , Milk/chemistry , Pasteurization/methods , Animals , Cattle , Chromatography, High Pressure Liquid , Hot Temperature , Maillard Reaction
16.
J Pharm Sci ; 109(7): 2189-2195, 2020 07.
Article in English | MEDLINE | ID: mdl-32240698

ABSTRACT

The treatment of peripheral nerve injury is still a challenge. The present study was aimed to fabricate a composite nerve conduit containing slow-released brain-derived neurotrophic factor (BDNF) and evaluate its therapeutic effects on peripheral nerve defect. BDNF and polylactic acid were mixed together and a BDNF-loaded composite conduit was fabricated by solvent evaporation method. The bioactivity of BDNF released from the composite conduit was measured by MTT assay. A rat sciatic nerve defect model was used to compare regeneration potentials of autologous nerve graft, conduit filled with saline, conduit filled with BDNF solution and BDNF composite conduit. Nerve-regeneration was evaluated 3 months after surgery. The results demonstrated BDNF composite conduits prepared in this study remained bioactive for at least 3 months, and can promote the regeneration of sciatic nerve with a 10-mm gap in rats.


Subject(s)
Brain-Derived Neurotrophic Factor , Sciatic Nerve , Animals , Nerve Regeneration , Rats , Rats, Sprague-Dawley
17.
Environ Sci Pollut Res Int ; 27(15): 17446-17457, 2020 May.
Article in English | MEDLINE | ID: mdl-31129898

ABSTRACT

Slow and random transfer of pollutants and photo-induced carriers on photocatalysts causes loss of efficiency in photodegradation of contaminants. Enhancing and directing mass transfer of them are considered as two major methods for improving the photodegradation of pollutants over photocatalysts. Here in this work, we focused on the design of a novel photocatalyst which not only accelerated the transfer rate of Cr(VI) and electrons but also provided specific transfer routes for them. By careful characterizations, it is indicated that 2-((2-(2-aminoethylamino)ethylimino)methyl)phenol (AEMP) was covalently attached onto activated carbon (AC), which enhanced Cr(VI) transfer from bulk solution to AC through electrostatic or coordinative interactions. The external mass transfer coefficient (Kf) of Cr(VI) over TiO2/AC-AEMP was estimated as 1.75 × 10-6 m s-1, which was ~ 12.79 and ~ 5.96 times that of TiO2 and TiO2/AC, respectively. Dense and homogeneous heterojunctions between AC and TiO2 were acquired synchronically by forming Ti-O-C linkages, which increased traveling of electrons from TiO2 to AC. Accordingly, Cr(VI) can capture photo-induced electrons on the surface of AC via concrete routes and then be reduced efficiently. The results showed that the photoreduction rate of Cr(VI) on TiO2/AC-AEMP reached to ~ 92.7%, and the overall photocatalytic activity of this well-designed TiO2/AC-AEMP has been enhanced significantly by 5.5 times compared to TiO2/AC. The enhanced photocatalytic activity of TiO2/AC-AEMP was mainly attributed to an improved synergetic process of mass transfer-induced adsorption-photoreduction by forming specific transfer routes for accelerative motion of Cr(VI) and electrons. This work provides a feasible strategy to improve the photoactivity of photocatalysts for the degradation of pollutants by effective mass transfer. Graphical abstract.


Subject(s)
Charcoal , Electrons , Adsorption , Catalysis , Chromium , Titanium
18.
R Soc Open Sci ; 6(4): 182195, 2019 Apr.
Article in English | MEDLINE | ID: mdl-31183142

ABSTRACT

Mesoporous ceramic functional nanomaterials (MCFN) is a self-assembled environmental adsorbent with a monolayer molecular which is widely used in the treatment of industrial wastewater and contaminated soil. This work aimed to study the relationship between the adsorption behaviour of Cd(II) by MCFN and contact time, initial concentration, MCFN dosage, pH, oscillation rate and temperature through a batch adsorption method. The adsorption kinetic and isotherm behaviours were well described by the pseudo-second-order and Langmuir models. The batch characterization technique revealed that MCFN had several oxygen-containing functional groups. Using Langmuir model, the maximum adsorption capacity of MCFN for Cd(II) was 97.09 mg g-1 at pH 6, 25°C, dosage of 0.2 g and contact time of 180 min. Thermodynamic study indicated that the present adsorption process was feasible, spontaneous and exothermic at the temperature range of 25-55°C. The results of this study provide an important enlightenment for Cd removal or preconcentration of porous ceramic nanomaterial adsorbents for environmental applications.

19.
Water Sci Technol ; 80(10): 1919-1930, 2019 Nov.
Article in English | MEDLINE | ID: mdl-32144224

ABSTRACT

In this work, particles of activated carbon supported by Fe-N-TiO2 (Fe-N-TiO2/AC) were synthesized and used as the three-dimensional (3D) particle electrode for folic acid wastewater treatment in the 3D electrolysis and photocatalysis coupling process. The structure, morphology, and physical and electrochemical properties of the Fe-N-TiO2/AC particles were characterized, and the results showed that Fe-N-TiO2 was bound on the surface of AC particles by chemical attachment, and the Fe-N-TiO2/AC particles had better capability of adsorption and charge transfer as compared with the TiO2/AC particles. The effects of key operating parameters in the reaction process, including the current density (optimum 0.6 mA/cm2), aeration (optimum 5 L/min), pH value (optimum 5) and the ratio of Fe-N-TiO2/AC particles to cellulose acetate film coating AC particles (optimum 4:1), were optimized regarding the total oxygen carbon (TOC) removal. Under the optimum conditions, TOC removal from folic acid wastewater reached 82.4% during 120 min photoelectrocatalysis. The kinetic analysis and mechanism study showed that the degradation process fitted to the second-order kinetic model better than to the first-order, and the system exhibited synergistic effects in inhibiting photogenic electron-hole recombination and improving electrolytic efficiency. At the same time, this system has the ability to overcome the interference of the strong ionic strength in folic acid wastewater.


Subject(s)
Wastewater , Water Pollutants, Chemical , Catalysis , Charcoal , Folic Acid , Kinetics , Titanium
20.
ACS Omega ; 3(10): 13170-13178, 2018 Oct 31.
Article in English | MEDLINE | ID: mdl-31458037

ABSTRACT

A novel environmental decalcifying agent was prepared with allylpolyethoxy amino carboxylate (APEAA), hydroxyethyl acrylate (HEA), and maleic anhydride (MA) by means of free-radical polymerization in an aqueous solution. The morphology and structure of the samples were characterized through scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectrometry, and 1H nuclear magnetic resonance (1H NMR) spectra. The molecular-weight distribution of APEAA-HEA-MA was determined by the gel permeation chromatography method. APEAA-HEA-MA was used as a green decalcifying agent to remove calcium from crude petroleum, and the impact of factors such as monomer ratio, copolymerization time, dosages, and desalination temperature was analyzed. It is found that the decalcification rate of APEAA-HEA-MA could reach to its maximum, and the calcium removal efficiency was approximately 97.88% when the monomer molar ratio of APEAA-HEA-MA was 1:2:5, the reaction time of copolymerization was 2 h, the dosage was 100 ppm, and the desalination temperature was 100 °C. This research work can promote the exploration on facile synthesis of a novel terpolymer and its potential application in refinery desalting processes.

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