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1.
Zhongguo Yi Liao Qi Xie Za Zhi ; 45(5): 507-511, 2021 Sep 30.
Artigo em Chinês | MEDLINE | ID: mdl-34628762

RESUMO

A 3D printing based wrist orthosis device was developed. After collecting the contour information of the carpal and metacarpophalangeal joints of the patients with a 3D scanner, the wrist orthotics were designed to meet the individual needs of the patients according to the relevant requirements of biomechanics. Choose TPU (thermoplastic polyurethanes) materials for preparation of 3D printing. It can functionally assist the smart brace after stroke patients with hemiplegia early rehabilitation training, the use of orthoses carry MPU6050 inertial sensor, magnetometer, time module device such as a sensor and monitor its movements and record the training time, ensure safe efficient rehabilitation training, help patients return to a normal life as soon as possible.


Assuntos
Acidente Vascular Cerebral , Punho , Humanos , Aparelhos Ortopédicos , Impressão Tridimensional , Articulação do Punho
2.
Molecules ; 26(19)2021 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-34641555

RESUMO

Folate is a vitamin beneficial for humans that plays an important role in metabolism, but it cannot be well supplemented by food; it is necessary to supplement it in other ways. Based on this consideration, a novel crystal form C of 6S-5-methyltetrahydrofolate calcium salt (MTHF CAC) was obtained. To explore the difference between MTHF CAC and the crystal form Ⅰ of 6S-5-methyltetrahydrofolate calcium salt (MTHF CA) as well as an amorphous product of 6S-5-methyltetrahydrofolate glucosamine salt (MTHF GA), their stability and pharmacokinetic behaviours were compared. The results of high-performance liquid chromatography coupled with ultraviolet detection analysis indicated that MTHF CAC showed a better stability than MTHF CA and MTHF GA. After oral administration of MTHF CAC, MTHF CA, and MTHF GA to male rats, the MTHF concentrations were analysed using a validated liquid chromatography-tandem mass spectrometry, and the pharmacokinetic parameters were compared. The mean residence times (0-t) of MTHF CAC, MTHF CA, and MTHF GA were 3.7 ± 1.9 h, 1.0 ± 0.2 h (p < 0.01), and 1.5 ± 0.3 h (p < 0.05), respectively. The relative bioavailability of MTHF CAC was calculated to be 351% and 218% compared with MTHF CA and MTHF GA, respectively, which suggests that MTHF CAC can be better absorbed and utilized for a longer period of time.

3.
Plant Dis ; 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34609206

RESUMO

Chinese catalpa, Catalpa bungei C.A. Mey is native to China and has been widely cultivated as an important tree species for timber and ornamental purposes (Tao et al. 2019). The properties and high durability of the wood can resist the damage caused by microorganisms and insects (Xiao Y et al. 2019). In September 2020, stem cankers were observed in 5-year-old and 3-year-old C. bungei in a pilot experiment field covering 16-hectare area in Shuyang city (Jiangsu province, China) and in a nursery in Binhai city (Jiangsu Province, China), respectively. The disease incidence in both locations was about 1% to 3%. The typical disease symptoms include small to large, dark-brown and irregular-sunken canker around and along the stem under 2 meters from the stem base. The phloem and xylem of the symptomatic stem were dark brown and the xylem had larger necrosis than the phloem. The cross section of the diseased stem was partially died. The symptomatic stem were collected in both locations for pathogen isolation. In total, seven purified isolates from the diseased samples were obtained using potato dextrose agar (PDA) following standard isolation protocol (Huang et al. 2019). In order to determine the pathogenicity, 3-year-old Chinese catalpa seedlings were artificially inoculated with each of the seven isolates in April 2021. After removing the bark of the stem by a sterilized punch (diameter 6mm), an agar plug (diameter 6mm) pre-colonized by the isolate was inoculated to the stem and the inoculation point was sealed with parafilm. The agar plug without pre-colonization was used as control. Six tree seedlings were inoculated for each isolate. Ten days after inoculation, only the treatment with isolate QS.1 showed obvious discoloration around the inoculation point. One month after inoculation, the canker around the inoculation point was formed (3.4 cm ± 1.0 cm) and spread to the xylem, similar to the symptoms observed in the field. Isolate QS.1 was re-isolated successfully from the inoculated stem based on morphological characters, confirming the Koch's postulates and QS.1 as the causal pathogen. The isolate QS.1 formed white colonies with abundant aerial mycelia on V8 juice agar and produced a large amount of persistent and papillary ovoid sporangia with size of 22 ~ 45µm (average 31µm) × 18 ~ 39µm (average 23µm) in 10% aqueous solution of V8. The spore was spherical with thick-wall and diameter of 24 ± 3.9µm. The morphology of QS.1 is similar to that of Phytophthora nicotianae. The genomic DNA of representative isolate QS.1 was extracted from mycelium by a modified CTAB method (Murray et al. 1980). The rDNA internal transcribed spacer (ITS) region, ß-tubulin and EF1-α genes were amplified and sequenced with primers ITS1/ITS4 (White et al. 1990), BTub_F1/TUBUR1 (L. et al. 2004) and EF1A_for/EF1A_rev (Blair et al. 2008), respectively. The BLAST results of these sequences (Accession No. MZ646302, MZ672116, and MZ675589, respectively) showed 99%, 100% and 100% identity with sequences of P. nicotianae (Accession No. KJ494902, KY205750, and MH359041), respectively. Based on the morphological characteristics and DNA analysis, isolate QS.1 was identified as P. nicotianae. To our best knowledge, this is the first report of P. nicotianae causing stem canker on Chinese Catalpa. This disease may pose potential threat on Catalpa due to the increase in Catalpa planting for economic and ecological purposes in China.

4.
Bioengineered ; 12(1): 7432-7445, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34605340

RESUMO

Bruton's tyrosine kinase (BTK) is involved in the diabetogenic process and cerebral ischemic injury. However, it remained unclear whether BTK inhibition has remedial effects on ischemia/reperfusion (I/R) injury complicated with diabetes. We aim to investigate the regulatory role and potential mechanism of ibrutinib, a selective inhibitor of BTK, in cerebral I/R injured diabetic mice. The cytotoxicity and cell vitality tests were performed to evaluate the toxic and protective effects of ibrutinib at different incubating concentrations on normal PC12 cells or which were exposed to high glucose for 24 h, followed by hypoxia and reoxygenation (H/R), respectively. Streptozotocin (STZ) stimulation-induced diabetic mice were subjected to 1 h ischemia and then reperfusion. Then the diabetic mice received different dosages of ibrutinib or vehicle immediately and 24 h after the middle cerebral artery occlusion (MCAO). The behavioral, histopathological, and molecular biological tests were then performed to demonstrate the neuroprotective effects and mechanism in I/R injured diabetic mice. Consequently, Ibrutinib improved the decreased cell viability and attenuated oxidative stress in the high glucose incubated PC12 cells which subjected to H/R injury. In the I/R injured diabetic mice, ibrutinib reduced the cerebral infarct volume, improved neurological deficits, ameliorated pathological changes, and improved autophagy in a slightly dose-dependent manner. Furthermore, the expression of PI3K/AKT/mTOR pathway-related proteins were significantly upregulated by ibrutinib treatment. In summary, our finding collectively demonstrated that Ibrutinib could effectively ameliorate cerebral ischemia/reperfusion injury via ameliorating inflammatory response, oxidative stress, and improving autophagy through PI3K/Akt/mTOR signaling pathway in diabetic mice.

5.
Seizure ; 92: 216-220, 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34600301

RESUMO

PURPOSE: Epileptic seizures in myelin oligodendrocyte glycoprotein (MOG) antibody-associated disorders (MOGAD) have been increasingly reported in the past two decades. However, the characteristics and possible mechanism largely remain unknown. This study aimed to investigate the clinical characteristics and immune mechanism of epileptic seizures in children with MOGAD. METHODS: We conducted a retrospective single-center case-control study from February 2019 to February 2021. Clinical characteristics and immune parameters of enrolled patients with seizures (n = 12) in MOGAD (n = 32), as compared with the antibody-negative (n = 13) and control (n = 23) groups were then analyzed. RESULTS: Seizures occurred in 24.5% (12/49, including cases that were not enrolled) of MOGAD. In this group, magnetic resonance imaging (MRI) abnormalities, especially unilateral cortical lesion and leptomeningeal enhancement, were more frequent in patients with seizures than in individuals without seizures (p < 0.05). Levels of thyroid peroxidase antibodies (TPOAb) in the seizure+/MOG+ group were significantly (p < 0.05) higher than those in the seizure-/MOG+ and control groups, whereas no significant differences as compared with the seizure+/MOG- group were observed. TPOAb level and brain MRI performance may be associated with disease course, since two cases with increased TPOAb and abnormal brain MRI were reported, after a second seizure attack occurred. CONCLUSION: Unilateral cerebral cortical encephalitis and isolated seizures, especially in clusters and focal seizures, may be special phenotypes of seizures in MOG-AD. TPOAb may be associated with seizures in immune-related neurological diseases, but not a specific marker of MOGAD. Therefore, TPOAb may be considered but not strongly recommended to be monitored in MOGAD.

6.
J Sex Med ; 2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34600862

RESUMO

BACKGROUND: The psychological and sexual health of different populations are negatively affected during the coronavirus disease 2019 (COVID-19) pandemic. However, little is known about psychological distress and erectile function of male recovered patients with COVID-19 in the long term. AIM: We aimed to evaluate psychological distress and erectile function of male recovered patients with COVID-19 in the mid-to-long terms. METHODS: We recruited 67 eligible male recovered patients with COVID-19 and followed them up twice within approximately 6 months of recovery time. The psychological distress and erectile function were assessed by validated Chinese version of paper questionnaires. OUTCOMES: The primary outcomes were Symptom Checklist 90 questionnaire for psychological distress and International Index of Erectile Function-5 for erectile function. RESULTS: In the first visit, COVID-19 patients with a median recovery time of 80 days mainly presented the following positive symptoms: Obsessive-Compulsive, additional items (ADD), Hostility, Interpersonal Sensitivity, Depression, and Somatization; while the dimension scores in Somatization, Anxiety, ADD, and Phobia were higher than Chinese male norms. Besides, the prevalence of erectile dysfunction (ED) in the first-visit patients was significantly higher than Chinese controls. In the second visit, the primary psychological symptoms of COVID-19 patients with a median recovery time of 174 days were Obsessive-Compulsive, ADD, Interpersonal Sensitivity, and Hostility, while all dimensions scores of Symptom Checklist 90 were lower than Chinese male norms. Moreover, second-visit patients had no significant difference with Chinese controls in ED prevalence. In addition, it suggested that GSI was the independent risk factor for ED in the regression analysis for the first-visit patients. CLINICAL IMPLICATIONS: The study showed the changes of psychological symptoms and erectile function in COVID-19 recovered patients, and provided reference on whether psychological and sexual supports are needed after a period of recovery. STRENGTHS AND LIMITATIONS: To our knowledge, it is the first study to comprehensively evaluate the psychological distress and erectile function of COVID-19 recovered patients in the mid-to-long terms. The main limitations were the low number of analyzed participants, and the psychological distress and erectile function of healthy Chinese men over the same period were not evaluated, and the psychological and sexual related data of participants prior to COVID-19 were not available. Additionally, there was a selection bias in comparing COVID-19 patients with healthy controls. CONCLUSION: With less impact of COVID-19 event, the impaired erectile function and psychological distress improved in COVID-19 recovered patients with a recovery time of nearly half a year. Hu B, Ruan Y, Liu K, et al. A Mid-to-Long Term Comprehensive Evaluation of Psychological Distress and Erectile Function in COVID-19 Recovered Patients. J Sex Med 2021;XX:XXX-XXX.

7.
J Clin Invest ; 131(17)2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34623332

RESUMO

We studied a child with severe viral, bacterial, fungal, and parasitic diseases, who was homozygous for a loss-of-function mutation of REL, encoding c-Rel, which is selectively expressed in lymphoid and myeloid cells. The patient had low frequencies of NK, effector memory cells reexpressing CD45RA (Temra) CD8+ T cells, memory CD4+ T cells, including Th1 and Th1*, Tregs, and memory B cells, whereas the counts and proportions of other leukocyte subsets were normal. Functional deficits of myeloid cells included the abolition of IL-12 and IL-23 production by conventional DC1s (cDC1s) and monocytes, but not cDC2s. c-Rel was also required for induction of CD86 expression on, and thus antigen-presenting cell function of, cDCs. Functional deficits of lymphoid cells included reduced IL-2 production by naive T cells, correlating with low proliferation and survival rates and poor production of Th1, Th2, and Th17 cytokines by memory CD4+ T cells. In naive CD4+ T cells, c-Rel is dispensable for early IL2 induction but contributes to later phases of IL2 expression. The patient's naive B cells displayed impaired MYC and BCL2L1 induction, compromising B cell survival and proliferation and preventing their differentiation into Ig-secreting plasmablasts. Inherited c-Rel deficiency disrupts the development and function of multiple myeloid and lymphoid cells, compromising innate and adaptive immunity to multiple infectious agents.

8.
Nanoscale ; 13(32): 13604-13609, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34477634

RESUMO

The alkaline electrocatalytic hydrogen evolution reaction (HER) is a potential way to realize industrial hydrogen production. However, the sluggish process of H2O dissociation, as well as the accumulation of OH- around the active sites, seriously limit the alkaline HER performance. In this work, we developed a unique CoS2 needle array grown on a carbon cloth (NAs@C) electrode as an alkaline HER catalyst. Finite-element simulations revealed that CoS2 needle arrays (NAs) induce stronger local electric field (LEF) than CoS2 disordered needles (DNs). This LEF can greatly repel the local OH- around the active sites, and then promote the forward H2O dissociation process. The local pH changes of the electrode surface confirmed the lower OH- concentration and stronger local pseudo-acidic environment of NAs@C compared to those of DNs@C. As a result, the NAs@C catalyst exhibited a low HER overpotential of 121 mV at a current density of 10 mA cm-2 in 1 M KOH, with the Tafel slope of 59.87 mV dec-1. This work provides a new insight into nanoneedle arrays for the alkaline HER by electric field-promoted H2O dissociation.

9.
Artigo em Inglês | MEDLINE | ID: mdl-34523088

RESUMO

The effects of Na-montmorillonite (Na-Mt) content and curing age on enzyme-induced carbonate precipitation (EICP)-treated soil were studied. First, the effects of Na-Mt addition on the urease activity, Ca2+ precipitation rate, and pH of the solution were analyzed through tube tests. Then, Na-Mt-modified EICP was used to reinforce silty sand in the Yellow River flooding area in China. The solidification effect and action mechanism of Na-Mt were investigated via the unconfined compressive strength (UCS) test, calcium carbonate content (CCC) measurement, X-ray diffraction, and scanning electron microscope analyses, wherein soil treated by conventional EICP and soil treated with Na-Mt alone were considered the control group. Na-Mt improved the urease activity and Ca2+ precipitation rate, lowered the pH, increased the CaCO3 production through chelation, then regulated the morphology of the CaCO3 crystals and facilitated the formation of densely aggregated calcite. The CCC and mechanical parameters increased rapidly during the first 7 days of curing, and then slowed down. The incorporation of 8% Na-Mt enhanced the UCS and Ca2+ utilization ratio at curing age of 7 days by 1.4 and 2.72 times, respectively, compared with that of traditional EICP; and the optimal Na-Mt content was identified to be 8%. At Na-Mt contents lower than 8%, the mathematically expressed improvement effect of the Na-Mt-modified EICP on the soil strength was greater than the arithmetic sum of that when these two approaches applied individually; this result confirms that the Na-Mt-modified EICP technique proposed herein is an efficient approach for solidifying fine-grained soil.

10.
Commun Biol ; 4(1): 1034, 2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34465887

RESUMO

COVID-19 has caused numerous infections with diverse clinical symptoms. To identify human genetic variants contributing to the clinical development of COVID-19, we genotyped 1457 (598/859 with severe/mild symptoms) and sequenced 1141 (severe/mild: 474/667) patients of Chinese ancestry. We further incorporated 1401 genotyped and 948 sequenced ancestry-matched population controls, and tested genome-wide association on 1072 severe cases versus 3875 mild or population controls, followed by trans-ethnic meta-analysis with summary statistics of 3199 hospitalized cases and 897,488 population controls from the COVID-19 Host Genetics Initiative. We identified three significant signals outside the well-established 3p21.31 locus: an intronic variant in FOXP4-AS1 (rs1853837, odds ratio OR = 1.28, P = 2.51 × 10-10, allele frequencies in Chinese/European AF = 0.345/0.105), a frameshift insertion in ABO (rs8176719, OR = 1.19, P = 8.98 × 10-9, AF = 0.422/0.395) and a Chinese-specific intronic variant in MEF2B (rs74490654, OR = 8.73, P = 1.22 × 10-8, AF = 0.004/0). These findings highlight an important role of the adaptive immunity and the ABO blood-group system in protection from developing severe COVID-19.


Assuntos
COVID-19/etnologia , COVID-19/genética , Grupos Étnicos/genética , Estudo de Associação Genômica Ampla , Predisposição Genética para Doença/genética , Humanos , Íntrons/genética , Polimorfismo de Nucleotídeo Único
11.
Artigo em Inglês | MEDLINE | ID: mdl-34550636

RESUMO

Atomically dispersed transition metal sites have been extensively studied for CO 2 electroredution reaction (CO 2 RR) to CO due to their robust CO 2 activation ability. However, the strong hybridization between directionally localized d orbits and CO vastly limits CO desorption and thus the activities of atomically d ispersed transition metal sites. In contrast, s-block metal sites possess nondirectional ly delocalized 3s orbits and hence weak CO adsorption ability, providing a promising way to solve the suffered CO desorption issue. Herein , we constructed atomically dispersed magnesium atoms embedded in graphitic carbon nitride ( Mg-C 3 N 4 ) through a facile heat treatment for CO 2 RR . Theoretical calculations show that the CO desorption on Mg sites is easier than that on Fe and Co sites. This theoretical prediction is demonstrated by experimental CO temperature program desorption and in-situ attenuated total reflection infrared spectroscopy. As a result, Mg-C 3 N 4 exhibits a high turnover frequency of ~ 18,000 per hour in H-cell and a large current density of -300 mA/cm 2 in flow cell , under a high CO Faradaic efficiency ≥90% in KHCO 3 electrolyte . This work sheds a new light on s-block metal sites for efficient CO 2 RR to CO.

12.
Technol Cancer Res Treat ; 20: 15330338211038492, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34520294

RESUMO

Background: Cancer cells have properties similar to those of stem cells, including high proliferation and self-renewal ability. NANOG is the key regulatory gene that maintains the self-renewal and pluripotency characteristics of embryonic stem cells. We previously reported that knockdown of the pluripotent stem cell factor NANOG obviously reduced the proliferation and drug-resistance capabilities of esophageal squamous cell carcinoma (ESCC). In this study, we gained insights into the potential regulatory mechanism of NANOG, particularly in ESCC. Methods: NANOG was ectopically expressed in the Eca-109 cell line via pcDNA3.1 vector transfection. The mRNA expression of different genes was detected using quantitative real-time polymerase chain reaction, and protein quantification was performed by western blotting. The enzyme-linked immunosorbent assay was used to detect the expression of interleukin 6 (IL-6). The capabilities of proliferation, migration, and invasion were investigated using cell count and Transwell assays. The tumor sphere-forming assay was used to investigate the sphere formation capacity of cancer stem cells. Results: The expression of NANOG promoted the cell proliferation and sphere formation capacity of cancer stem cells in a dose-dependent manner. IL-6-mediated activation of signal transducer and activator of transcription 3 (STAT3) was closely related to the expression of NANOG in ESCC. Consistently, the target genes of STAT3, including CCL5, VEGFA, CCND1, and Bcl-xL, were upregulated upon the overexpression of NANOG. Conclusion: These results revealed that the expression of NANOG promotes cell proliferation, invasion, and stemness via IL-6/STAT3 signaling in ESCC.

13.
Clin Ther ; 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34579971

RESUMO

PURPOSE: The combination of vancomycin and piperacillin/tazobactam (VAN + PTZ) provides a broad spectrum of activity against multiple pathogens. However, a major issue in previous research concerned significant nephrotoxicity associated with this drug combination, and most studies have been conducted in American and European countries, with no similar data available from China. Therefore, this study evaluated the nephrotoxic effects of VAN + PTZ in a large-scale Chinese cohort to determine the prevalence of acute kidney injury (AKI) in this population by comparing PTZ and vancomycin monotherapies and the combined use of vancomycin and ß-lactam antibiotics. METHODS: This retrospective cohort study identified adult patients who received vancomycin either as monotherapy or in combination with PTZ or carbapenem (VAN + CAR) for at least 48 hours at Jiangsu Province Hospital from January 1, 2017, to December 31, 2018. Patients were also evaluated for the development of AKI, defined according to the Kidney Disease Improving Global Outcome criteria. Duration of vancomycin exposure, steady-state trough vancomycin concentrations, and other risk factors for AKI were assessed. A Bayesian network meta-analysis was conducted to validate our results and comparatively evaluate the nephrotoxicity of ß-lactam antibiotics in combination with vancomycin. FINDINGS: In all, 752 patients were included in the present study. The prevalence of AKI was higher in the VAN + PTZ group than in the VAN and VAN + CAR groups (15.2% vs 4.0% and 6.0%, respectively). After adjustment for confounding factors, VAN + PTZ was still related to AKI (odds ratio [OR] = 4.37; 95% CI, 1.65-11.59; P = 0.003). The network meta-analysis indicated that VAN + PTZ was associated with a significantly higher risk for AKI than was VAN (OR = 3.23; 95% CI, 2.50-4.35), PTZ (OR = 2.86; 95% CI, 1.92-4.12), VAN + cefepime (FEP) (OR = 2.37; 95% CI, 1.80-3.19), or VAN + CAR (OR = 2.28; 95% CI, 1.64-3.21). However, there was no significant difference with respect to AKI prevalence among the VAN, PTZ, VAN + FEP, and VAN + CAR groups. IMPLICATIONS: The prevalence of AKI was higher with VAN + PTZ therapy than with VAN or PTZ monotherapy or with the concurrent use of VAN and FEP or CAR in our study. Clinicians should adequately assess renal function and consider this differential risk for nephrotoxicity when choosing empiric antibiotics in hospitalized patients to minimize the rates of AKI.

14.
Ecotoxicol Environ Saf ; 225: 112806, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34555716

RESUMO

Ionic liquids (ILs) are widely used for their physical and chemical properties. Toxicological assessments of ILs could help to avoid their threat to human health, but these are rarely reported, and no assessments of IL neurotoxicity in mammals have been performed. Here, we aimed to evaluate the neurotoxicity of chronic 1-octyl-3-methylimidazolium hexafluorophosphate ([C8mim][PF6]) (0, 1 mg/kg) exposure during development on rats. Our results indicated that chronic exposure to low-dose ([C8mim][PF6]) induces behavioural abnormalities, including cognitive deficits, social communication disorders, and sensory gating function impairment. Moreover, rats subjected to chronic ([C8mim][PF6]) exposure showed hypofunction of glutamatergic excitatory synapses, including increased expression of NMDA receptor subunits, increased density and immaturity of dendritic spines, and increased expression of PSD95. Additionally, ([C8mim][PF6]) exposure resulted in hippocampal-specific inflammatory activation, indicated by increased levels of proinflammatory factors, elevated nuclear localisation of NF-κB, and activation of microglia and astrocytes. In conclusion, chronic exposure to low-dose ([C8mim][PF6]) induced neurotoxicity, including damage to glutamatergic excitatory synapses and inflammatory activation, which may illuminate the associated behavioural abnormalities. The results presented here may be helpful for the safe use of ILs in the future.


Assuntos
Disfunção Cognitiva , Síndromes Neurotóxicas , Animais , Astrócitos , Microglia , NF-kappa B , Síndromes Neurotóxicas/etiologia , Ratos
15.
J Hazard Mater ; 416: 126156, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492936

RESUMO

It is of great importance to safely dispose nuclear wastes with the development of nuclear industries. Past approaches to this problem have included immobilizing radioactive cesium in Portland cement-based matrices; however, the leaching rates of cesium are relatively high, especially as the leaching temperature increases. This paper explores a high-efficiency and cost-effective approach for encapsulating cesium using a sulfoaluminate cement (SAC) matrix, which was prepared via synergetic use of industrial solid wastes. Leaching results showed that, the apparent diffusion coefficient values of cesium were only ~1.4 × 10-15 cm2/s and ~5 × 10-18 cm2/s at 25 â„ƒ and 90 â„ƒ leaching conditions, respectively. These values were several orders of magnitude lower when compared with previously reported values, indicating the excellent encapsulation performance of the solid-waste-based SAC for cesium. Moreover, the heavy metals contained in the industrial solid waste were also effectively immobilized. A mechanistic analysis revealed that cesium was encapsulated in the SAC matrices stably by a physical effect. Finally, a life cycle assessment and economic analysis indicated that this approach was environmental-friendly, cost-effective, and energy-saving. This work provides a promising strategy for effective encapsulation of cesium and synergetic treatment of industrial solid wastes.


Assuntos
Resíduos Radioativos , Resíduos Sólidos , Césio , Materiais de Construção , Resíduos Industriais
16.
Sensors (Basel) ; 21(18)2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34577233

RESUMO

Site investigations of the soils are considered very important for evaluation of the site conditions, as well as the design and construction for the project built in it. Taihu tunnel is thus far the longest tunnel constructed in the lake in China, with an entire length of over 10 km. However, due to the very insufficient site data obtained for the lacustrine clay in the Taihu lake area, a series of self-boring pressuremeter (SBPM) field tests was therefore carried out. Undrained shear strengths were deduced from the SBPM test, with the results showing generally higher than those obtained from the laboratory tests, which may be attributed to the disturbance to the soil mass during the sampling process. Degradation characteristics of the soil shear modulus (Gs) were mainly investigated, via a thorough comparison between different soil layers, and generally, the shear modulus would cease its decreasing trends and become stable when the shear strain reaches over 1%. Meanwhile, it was found that a linear relationship between the plasticity index and the shear modulus, and between the decay rate of the shear modulus and the plasticity index as well, could be developed. Further statistical analysis over the undrained shear strength and shear modulus distribution of the soils shows that the undrained shear strength of the soils follows a normal distribution, while the shear modulus follows a log-normal distribution. More importantly, the spatial correlation length of the shear modulus is found much smaller than that of the undrained strength.


Assuntos
Poluentes do Solo , Solo , China , Argila , Lagos
17.
Carbohydr Polym ; 273: 118552, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34560964

RESUMO

In this study, luteolin-oxidized lotus root starch (OLRS) nanoparticles (NPs) were developed to improve the stability and antioxidant activity of luteolin. Results showed that a stable luteolin-OLRS NPs was formed using luteolin and OLRS (oxidation degree, 15%) in the weight ratio of 3:1, as well as anti-solvent and solvent in the volume ratio of 10:1. Under this condition, the particle size, polydispersity index and zeta-potential of luteolin-OLRS NPs was 305 nm, 0.173 and -20.8 mV, respectively. The analysis of transmission electron microscopy, X-ray diffractometer and Fourier transform infrared spectroscopy demonstrated that the luteolin was successfully encapsulated in OLRS NPs, giving an encapsulation efficiency of 87.2%. The release characteristic and antioxidant activity of encapsulated luteolin were further investigated. Results exhibited that the OLRS NPs enabled luteolin to be stable in simulated gastric fluid and sustained release in simulated intestinal fluid, leading to the enhancement of antioxidant activity of luteolin.

18.
Food Res Int ; 147: 110542, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34399519

RESUMO

Some bioactive ingredients in foods are unstable and easily degraded during processing, storage, transportation and digestion. To enhance the stability and bioavailability, some food hydrogels have been developed to encapsulate these unstable compounds. In this paper, the preparation methods, formation mechanisms, physicochemical and functional properties of some protein hydrogels, polysaccharide hydrogels and protein-polysaccharide composite hydrogels were comprehensively summarized. Since the hydrogels have the ability to control the release and enhance the bioavailability of bioactive ingredients, the encapsulation and release mechanisms of polyphenols, flavonoids, carotenoids, vitamins and probiotics by hydrogels were further discussed. This review will provide a comprehensive reference for the deep application of polysaccharide/protein hydrogels in food industry.


Assuntos
Hidrogéis , Polissacarídeos , Disponibilidade Biológica , Carboidratos da Dieta , Proteínas
19.
Artigo em Inglês | MEDLINE | ID: mdl-34360127

RESUMO

Mastering the coupling and coordination relationship and driving mechanism of urbanization and ecosystem service value (ESV) is of great significance to ecological protection and regional sustainable development. In this paper, the coupling coordination model, geographic detector and GWR model are used to analyze the spatio-temporal coupling interaction between urbanization and ESV and the spatial differentiation characteristics of influencing factors from 1995 to 2018. The results of the study are as follows: (1) During the study period, cities in the Yellow River Basin experienced accelerated urban expansion, and the ESV of forests, water and wetlands increased, which offset the reduction in ESV due to the expansion of construction land and farmland and grassland. (2) The degree of coupling and coordination between the two gradually improved, but the overall situation showed a low-level coupling and coordination process. Mild coupling coordination gradually increased, reaching an increase of 38.10%; severe imbalance types tended to disappear, decreasing by 52.38%, and coupling subtypes developed from lagging urbanization to ESV backward types. The high-value areas of the coupling coordination degree are distributed in the high-value areas of ESV in the north of the upper reaches, and the low-value areas are distributed in the cities of Henan and Shandong with high urbanization levels in the downstream and most resource-based cities in the middle reaches. (3) In addition, the spatial intensity of the effect of each dominant factor on the degree of coupling coordination is different. Economic growth, technological development, environmental regulations and the proportion of forest land have positive and belt-shaped alienation characteristics for the coupling and coordination of the two, and infrastructure and temperature show negative driving characteristics. Therefore, the coupling and coordination relationship between ESV and urbanization should be clarified to help future urban planning. On the basis of determining the regional environmental carrying capacity and the adjustment direction of the rational planning of land resources, the impact of urban barriers formed by administrative boundaries and natural geographical conditions on the development of urban agglomerations should be broken to achieve the overall high-quality and coordinated development of the basin.


Assuntos
Ecossistema , Urbanização , China , Cidades , Conservação dos Recursos Naturais , Rios
20.
Artigo em Inglês | MEDLINE | ID: mdl-34387083

RESUMO

The targeted synthesis of a novel ionic porous organic polymer (iPOP) was reported. The compound (denoted as QUST-iPOP-1) was built up through a quaternization reaction of tris(4-imidazolylphenyl)amine and cyanuric chloride, and then benzyl bromide was added to complete the quaternization of the total imidazolyl units. It featured a special exchangeable Cl-/Br--rich structure with high permanent porosity and wide pore size distribution, enabling it to rapidly and effectively remove environmentally toxic oxo-anions including Cr2O72-, MnO4-, and ReO4- and anionic organic dyes with different sizes including methyl blue, Congo red, and methyl orange from water. Notably, QUST-iPOP-1 showed ultra-high capacity values for radioactive TcO4- surrogate anions (MnO4- and ReO4-), Cr2O72-, methyl blue, and Congo red, and these were comparable to some reported compounds of exhaustive research. Furthermore, the relative removal rate was high even when other concurrent anions existed.

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