Application of atomic-scale mechanistic insights into carbon-catalyzed N2O reduction for kinetic modeling construction.

To achieve the collaborative elimination of N2O and carbon of potent greenhouse pollutants from automotive mobile sources, a chemical kinetic model is developed to accurately track the heterogeneous process of carbon-catalyzed N2O reduction based on density functional theory, with experimental data used to validate the model's reliability. The influence of carbon structure, site density, and surface chemical properties on N2O catalytic reduction can be analyzed within this system. Results reveal that the free-edge site of carbon accurately describes the catalytic reduction process of N2O. Adsorption of N2O to carbon edges in O-down, N-down, or parallel orientations exhibits an exothermic process with energy barriers. The N2O with O-down reduction pathway predominates due to the limitations imposed by the unitary carbon site. As the number of active carbon atoms at carbon edges increases, the N2O reaction mode tends towards parallel and N-down pathways, resulting in a significant enhancement of N2O conversion rates and a reduction in catalytic temperatures, with the lowest achievable temperature being 300 K. Furthermore, the triplet carbon structure exhibits higher efficiency in N2O catalytic reduction compared to the singlet carbon structure, achieving a remarkable N2O conversion rate of 93.8 % within the typical temperature exhaust window of diesel engines. This study supplies a breakthrough for carbon materials as catalysts for achieving high N2O conversion rates at low cost, which is important for the collaborative catalytic elimination of N2O and carbon black pollutants.

Effects of silver nanoparticles on maternal mammary glands and offspring development under lactation exposure.

The widespread applications of silver nanoparticles (AgNPs) throughout our daily lives have raised concerns regarding their environmental health and safety (EHS). Despite an increasing number of studies focused on the EHS impacts of AgNPs, there remain significant knowledge gaps with respect to their potential health impacts on susceptible populations, such as lactating mothers and infants. Herein, we aimed to investigate the deleterious effects of AgNPs with different sizes (20 and 40 nm) and surface coatings (PVP and BPEI) on maternal mice and their offspring following lactation exposure at doses of 20, 100 and 400 µg/kg body weight. We discovered that AgNPs could accumulate in the maternal mammary glands and disrupt the epithelial barrier in a dose-dependent manner. Notably, BPEI-coated AgNPs caused more damage to the mammary glands than PVP-coated particles. Importantly, we observed that, while AgNPs were distributed throughout the blood and main tissues, they were particularly enriched in the brains of breastfed offspring after maternal exposure during lactation, exhibiting exposure dosage- and particle coating-dependent patterns. Compared to PVP-coated nanoparticles, BPEI-coated AgNPs were more readily transferred to the offspring, possibly due to their enhanced deposition in maternal mammary glands. Moreover, we observed reduced body weight, blood cell toxicity, and tissue injuries in breastfed offspring whose dams received AgNPs. As a whole, these results reveal that maternal exposure to AgNPs results in the translocation of AgNPs into offspring via breastfeeding, inducing developmental impairments in these breastfed offspring. This study provides important new insights into the EHS impacts of AgNP consumption during lactation.

Modified Nutrition Risk in Critically ill is an effective nutrition risk screening tool in severely burned patients, compared with Nutrition Risk Screening 2002.

Objective: The present study aimed to evaluate the value of Modified Nutrition Risk in Critically ill (mNUTRIC) and Nutrition Risk Screening 2002 (NRS2002) in the prognosis of severely burned patients. Methods: The retrospective cohort study used medical data of severely burned patients admitted to the burn center of Shanghai Ruijin Hospital between January 2015 and September 2021. Demographics, clinical characteristics, laboratory nutritional indicators, mNUTRIC score and NRS2002 score were collected and analyzed in evaluation the value of two nutrition risk screening tools. Spearman correlation analysis was carried out to show the correlation between variables. The area under receiver operating characteristic (ROC) curve was used to assess the ability of mNUTRIC and NRS2002 to predict mortality. Kaplan-Meier survival curves and log-rank tests were conducted to compare the overall survival (OS). Multivariate Cox proportional hazard regression model was used to identify risk factors for 28-day mortality of severely burned patients. Results: A total of 429 adult patients with burn area larger than 30% total body surface area (TBSA) were included in this study. Incidence of nutrition risk was detected in 52.21% by mNUTRIC and 20.51% by NRS2002. However, mNUTRIC was superior to NRS2002 in predicting 28-day mortality (area under ROC curve: 0.795 vs. 0.726). Multivariate Cox regression analysis showed that high mNUTRIC [hazard ratio (HR) = 4.265, 95% CI = 1.469-12.380, P = 0.008] and TBSA (HR = 1.056, 95% CI = 1.033-1.079, P < 0.001) were independent predictors for 28-day mortality. After adjusting for covariates, high NRS2002 was not associated with 28-day mortality (P = 0.367). Conclusion: The present study illustrated the effectiveness of mNUTRIC as nutrition risk screening tool among severely burned patients. Early identification of nutrition risk may help to maximize benefits of nutritional therapy by providing more aggressive nutritional therapy for patients at nutrition risk.

Can white clover facilitate apple orchard residue composting?

Aiming to assess the efficiency of white clove (WC) as an alternative nitrogen source for composting and to facilitate the utilization of orchard waste, WC as compared with chicken manure (CM) was aerobically composted with apple tree leaves (ATL) in initial C/N ratios of 25(R25), 30(R30) and 35(R35). The results show that WC facilitated the rapid and harmless treatment of ATL with the compost temperature above 55°C for more than 3 days. After composting, for all final products, organic matter content was 69.9%-72.9%, electrical conductivity (EC) 1.48-2.31 ms cm-1, germination index (GI) more than 80% and C/N ratios less than 20. Among all treatments, the product from R30 was most nutrient-rich. Compared with CM, WC facilitated the harmless treatment of ATL and required less time for high quality compost production. It is concluded that WC is an excellent replacement for animal manure as a nitrogen source in field composting of orchard waste in areas with limited transportation. WC and ATL can produce high quality organic fertilizer and initial C/N ratio of 30 is recommended.

Positive effects of dietary supplementation of three probiotics on milk yield, milk composition and intestinal flora in Sannan dairy goats varied in kind of probiotics.

In this study, we investigated the effects of Saccharomyces cerevisiae (SC), Bacillus subtilis (BS) and Enterococcus faecalis (EF), singly and in combination, on the dry matter intake (DMI), milk production and composition, and faecal microflora of Saanen dairy goats. Fifty goats were randomly divided into five groups: (a) basal diet (control); (b) basal diet + SC; (c) basal diet + BS; (d) basal diet + EF; and (e) basal diet + mixed probiotics. Each treated animal received 5 g/d of probiotics for a total administration of 5 × 1,011 CFU/goat per day. The inclusion of B. subtilis and E. faecalis in the diet of lactating Saanen goats increased DMI (p < .05). Enhanced milk yield was observed with BS and EF. Milk fat percentage was significantly increased by feeding mixed probiotics compared with the control (p < .05); supplying SC, BS and mixed probiotics enhanced the protein percentage (p < .05). The milk lactose percentage in the SC and BS groups was higher than in the control (p < .05). The amount of milk total solids was higher after feeding EF or mixed probiotics than in the control group (p < .05). Non-fat solids showed no notable differences among groups (p > .05). There was no significant influence on gut bacterial abundance and diversity from adding these three probiotics, singly or in combination. Bacteroidales, Escherichia-Shigella and Christensenellaceae abundances were decreased by supplying these probiotics but Succinivibrionaceae increased. In conclusion, there were positive influences of probiotic feed supplementation on intake, milk performance and intestinal microecology.

[Determination of multi-element contents in gypsum by ICP-AES].

The content of multi-element in gypsum was determined by ICP-AES. The sample was pretreated by acid-soluble method or alkali-fusion method. Acid-soluble method is suitable for the determination of CaO, SOs, Al2O3, Fe2O3, MgO, K2O, Na2O, TiO2, P2O5, MnO, SrO and BaO. Alkali-fusion method is suitable for the determination of CaO, SO3, SiO2, Al2O3, Fe2O3, MgO, TiO2, P2O5, MnO, SrO, BaO and B2O3. Different series standard solutions were prepared considering the properties and content of elements and solution matrix. The limit of detection and quantification were confirmed for each element under their best analysis spectral lines. The recoveries of the two pretreatment methods were from 93% to 110%, besides that for TiO2 was 81%-87% as pretreated by acid-soluble method. All RSDs (n=6) of tests were from 0.70%-3.42%. The accuracies of CaO and SO3 with ICP-AES method were less than the chemical analysis method. The determination of CaO and SO3 with ICP-AES method is only suitable for the case of low accuracy requirement. The results showed that the method can be used for the determination of multi-element contents in gypsum, with simple operation, fast analysis and reliable results. Total elements can be analysed with both acid-soluble method and alkali-fusion method.