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Determining the appropriate soil cadmium (Cd) criteria for vegetable production is important for ensuring that the Cd concentrations of the vegetables meet food safety standards. The soil extractable Cd criteria for vegetable production are also essential for both food safety and environmental management, especially in areas with a high natural background level. In the present study, soil total and extractable Cd criteria were derived using the approach of species sensitivity distribution integrated with soil aging and bioavailability as affected by soil properties. A dataset of 90 vegetable species planted in different soils was compiled by screening the published in literature in five bibliographic databases using designated search strings. The empirical soil–plant transfer model was applied to normalize the bioaccumulation data. After normalization, the intra-species variability was reduced by 18.3 to 84.4%. The soil Cd concentration that would protect 95% (HC5) of the species was estimated by species sensitivity distribution curves that were fitted by the Burr III function. The soil Cd criteria derived from the added approach for risk assessment were proposed as continuous criteria based on a combination of organic carbon and pH in the soil. Criteria for total Cd and EDTA-extractable Cd in the soil ranged from 0.23 to 0.61 mg kg−1 and from 0.09 to 0.25 mg kg−1, respectively. Field experimental data were used to validate the applicability and validity of these criteria. Most of the predicted HC5 values in the field experimental sites were below the 1:1 line. These results provide a scientific basis for soil Cd criteria for vegetable production that will ensure food safety.

Objective and Impact Statement: The microspheres were widely utilized in the field of life sciences, and we have developed an innovative microelectromechanical system (MEMS)-based bioprinting technology (MBT) system for the preparation of the microspheres. The microspheres can be automatically and high-throughput produced with this cutting-edge system. Introduction and Methods: This paper mainly introduced a novel, efficient, and cost-effective approach for the microsphere fabrication with the MBT system. In this work, the whole microsphere production equipment was built and the optimal conditions (like concentration, drying temperature, frequency, and voltage) for generating uniform hydroxypropyl cellulose–cyclosporine A (HPC-CsA) and poly-l-lactic acid (PLLA) microspheres were explored. Results: Results demonstrated that the optimal uniformity of HPC-CsA microspheres was achieved at 2% (w/v) HPC-CsA mixture, 45 °C (drying temperature), 1,000 Hz (frequency), and 25 V (voltage amplitude). CsA microspheres [coefficient of variation (CV): ~9%] are successfully synthesized, and the drug encapsulation rate was 84.8%. The methodology was further used to produce PLLA microspheres with a diameter of ~2.55 μm, and the best CV value achieved 6.84%. Conclusion: This investigation fully highlighted the integration of MEMS and bioprinting as a promising tool for the microsphere fabrication, and this MBT system had huge potential applications in pharmaceutical formulations and medical aesthetics.

It is significant to establish an accurate model to predict cadmium (Cd) criteria for safe wheat production. More importantly, for better evaluation of the risk of Cd pollution in high natural background areas, the soil extractable Cd criteria are needed. In the present study, the soil total Cd criteria were derived using the method of cultivars sensitivity distribution integrated with soil aging and bioavailability as affected by soil properties. Firstly, the dataset that meet the requirements was established. Dataset from thirty-five wheat cultivars planted in different soils published in literature of five bibliographic databases were screened using designated search strings. Then, the empirical soil-plant transfer model was used to normalize the bioaccumulation data. Afterwards, the soil Cd concentration for protecting 95 % (HC5) of the species was calculated from species sensitivity distribution curves, and the derived soil criteria were obtained from HC5 prediction models that based on pH. The process of derivation for soil EDTA-extractable Cd criteria was the same way as the soil total Cd criteria. Soil total Cd criteria ranged from 0.25 to 0.60 mg/kg and soil EDTA-extractable Cd criteria ranged from 0.12 to 0.30 mg/kg. Both the criteria of soil total Cd and soil EDTA-extractable Cd were further validated to be reliable using data from field experiments. The results suggested that the criteria of soil total Cd and soil EDTA-extractable Cd in the study can ensure the safety of Cd in wheat grains and thereby enable local agricultural practitioners to develop appropriate management for croplands.

Abstract Background Gestational diabetes mellitus (GDM) seriously affects the health of mothers and babies, and there are still no effective early diagnostic markers. Therefore, it is necessary to find diagnostic biomarkers for screening GDM in early pregnancy. Circular RNA (circRNA) is more stable than linear RNA, and can be encapsulated in exosomes and participate in the pathological process of various diseases, which makes it a better candidate biomarker for various diseases. In this study, we attempted to identify the exosomal circRNA biomarkers for detecting early GDM. Methods We performed microarray analysis to compare the plasma exosomal circRNA expression profiles of three GDM patients 48 h before and 48 h after delivery. The repeatability of the expression of circRNAs were randomly validated by RT-PCR analysis. Pearson correlation analysis was applied to evaluate the correlation between circRNAs and OGTT level. ROC curve was established to assess the diagnostic value of circRNAs for GDM at different stages. Results Plasma exosomal hsa_circRNA_0039480 and hsa_circRNA_0026497 were highly expressed in GDM patients before delivery (P

The violate organic compounds (VOCs) emission from co-processing cement kiln has not been comprehensively investigated and evaluated. In this study, we sampled and determined the VOCs emitted from a typical co-processing cement kiln in Beijing, China. VOCs characteristics, ozone formation potential (OFP), and main odor components for the emitted gas were analyzed. Additionally, a Fuzzy Analytic Hierarchy Process (F-AHP) was innovatively applied to estimate the priority VOCs. The study shows that aromatic (36.6%) and oxygen contained VOCs (O-VOCs) (30.3%) were the most abundant VOCs, with a high average concentration of benzene (1622.0 μg/m3) and acrolein (1105.5 μg/m3). Acrolein, propene, benzene, 1-butane, and 1,3-butadiene were the dominate OFP compounds, with the corresponding average OFP concentration of 8325.6, 3768.2, 1167.9, 1065.9, and 1027.2 μg/m3, respectively. Acrolein was also found to be the dominate main odor component. Eleven VOCs, including one O-VOC, one halohydrocarbon, and nine alkenes, were screened out by F-AHP. Alkene was the priority VOCs category and acrolein was the most important VOC in the stack gas. The results of this study are helpful to systematically understand the VOCs’ characteristics, OFP, main odor components, and priority compounds of VOCs in the stack gas of co-processing cement kiln, and provide a new method for the screening of priority VOCs compounds.

It is significant to derive an appropriate cadmium (Cd) threshold for the rice to ensure that the Cd concentration of rice grains meets the food safety standards. In the present study, soil thresholds for Cd were derived using the method of species sensitivity distribution based on aging time, cultivars, and soil properties. Dataset from thirty-nine rice cultivars planted in different soils published in literature of five bibliographic databases were screened using designated search strings to explore their differences in Cd accumulation capacity in paddy soil. The empirical soil-plant transfer model was used to normalize the bioaccumulation data. Later, the soil Cd concentration for protecting 95% (HC5) of the cultivars was calculated using species sensitivity distribution curves fitted by the Burr III function. The soil Cd criteria derived from the added approach for risk assessment were proposed as continuous criteria based on the combination of soil pH and organic carbon in soil. Soil Cd criteria ranged from 0.34 to 1.18 mg/kg. The prediction model for HC5 was applied to field experimental data to validate its validity and applicability. The predicted Cd thresholds were less than the field experiment Cd thresholds. In conclusion, this study provided valuable and scientific bases for setting soil Cd criteria for paddy soils.

With the expansion of global trade and the deterioration of the marine environment, research on the sustainability of marine transport has drawn increasing scientific attention. This study takes the marine supply chain composed of Maersk and ports in 17 coastal cities in China as decision-making units (DMUs). It then chooses indicators from the three dimensions of economy, environment and society to evaluate the sustainable efficiency of the marine supply chain, Maersk and ports. In order to deal with the uncertain variables of the sustainability evaluation index, this study develops an uncertain network DEA model based on the uncertainty theory, and the computable equivalent form and proof are also provided. In addition, this study divides the decentralized marine supply chain into two modes, i.e., Maersk as leader and the port as leader, and it calculates their sustainable efficiency, respectively. These results suggest that the sustainable performance of ports is superior to that of Maersk, and the sustainable performance of the marine supply chain is better under the lead of ports, but most of the sustainable efficiencies of marine supply chains are inefficient. Therefore, ports should act as a catalyst for the development of the marine supply chain, and the management implications and suggestions for the economic, environmental, and social dimensions are also outlined at the conclusion.

Evaluating efficiency according to the different states of returns to scale (RTS) is crucial to resource allocation and scientific decision for decision-making units (DMUs), but this kind of evaluation will become very difficult when the DMUs are in an uncertain random environment. In this paper, we attempt to explore the uncertain random data envelopment analysis approach so as to solve the problem that the inputs and outputs of DMUs are uncertain random variables. Chance theory is applied to handling the uncertain random variables, and hence, two evaluating models, one for increasing returns to scale (IRS) and the other for decreasing returns to scale (DRS), are proposed, respectively. Along with converting the two uncertain random models into corresponding equivalent forms, we also provide a numerical example to illustrate the evaluation results of these models.

Self evaluation and peer evaluation in data envelopment analysis (DEA) are effective means to comprehensively reflect the efficiencies of decision-making units (DMUs). However, when some of the inputs and outputs of DMUs cannot be accurately observed, the traditional evaluation methods will lose their applicability. This paper attempts to treat the imprecise inputs and outputs as uncertain variables based on uncertainty theory and hence to propose a new uncertain DEA model for cross-efficiency evaluation via the evaluation of both self efficiency and peer efficiency. Moreover, the equivalent form and the proof of the new model are also presented for accurate calculation. Finally, a numerical example is given to illustrate the evaluation results.

Based on the concept of environmental carrying capacity (ECC), this study applies data envelopment analysis (DEA) and panel data analysis on panel data of 20 coastal ports in China from 2007 to 2012 to study the ECC mechanism of coastal ports. Research indicates that both port environmental technology level and environmental construction scale affect port ECC (PECC) with the latter dominating the changes in PECC. Additionally, economic development level and port throughput capacity positively impact PECC; educational investment negatively impacts PECC to a certain extent; and the degree of technological innovation and industrial transformation and upgrading have no obvious effect on PECC, indicating that science and technological investments did not achieve the desired output of industrial transformation and upgrading. Given the government's policy of advancing sustainable development and supply-side reform, this study provides policy guidance for the port to promote the construction of ecological civilization from the perspective of PECC. Keywords: Environmental carrying capacity, Environmental Kuznets Curve, Environmental Education Theory, Cost Theory, Data envelopment analysis

China's reform has led to rapid port enterprise development and improved major coastal port throughput capacity and loading efficiency. Modern port enterprises are important nodes in global supply chain integration and have begun to function as integrated logistics service centers. Qingdao port was used to evaluate enterprise supply chain risk. An improved AHP method was used to propose measures to strengthen port enterprise supply chain risk management. Port service process risk, operational risk, port relationship process risk, and external environment-associated risk are too high in this supply chain. To strengthen supply chain risk control, improved port service efficiency, enhanced port operational ability, strengthened membership management, and improved supply chain risk prevention mechanisms are required. Keywords: Supply chain, Risk management, Supply chain risk

The initiative of the 21st-Century Maritime Silk Road will not only enhance China's international trade with countries along the road, but will also bring opportunities and challenges to China's maritime shipping industry. This article examines correlations between freight rate and the export trade on the five shipping routes of the Maritime Silk Road by the VAR model. The empirical results show that among the five routes, on the Persian Gulf route and European route, export has a significantly negative impact on freight index; however, on the Southeast Asian route and Taiwanese route freight index has a significantly negative effect on exports. Finally, some strategies were put forward on the Chinese shipping market and industry. Keywords: The 21st-Century Maritime Silk Road, SCFI, Export Trade, VAR Model

When decision making units (DMUs) have internal structures with imprecise inputs and outputs, uncertain network data envelopment analysis (UNDEA) is appropriate to deal with the efficiency evaluation of these DMUs. However, a deep insight into clarifying the power’s differences between the internal structures of DMUs is a deficiency in the current UNDEA model. To address this issue, in this paper, we propose a new UNDEA model by differentiating the power asymmetry of each sub-stage with assumption of a two-stage system and demonstrate an additive relationship between stage 1 and stage 2 of each DMU. Moreover, the equivalent form and its proof of the new model are also presented for accurate calculation. Finally, a numerical example reflecting three different additive relationships between two sub-stages of DMUs is given to illustrate the results of evaluation.

The antioxidant activities in the Cabernet Sauvignon and Merlot wines from four wine grape-growing regions in China were measured by different analytical assays: 2,2-diphenyl-1-picrylhydrazyl (DPPH·), cupric reducing antioxidant capacity (CUPRAC), superoxide radical-scavenging activity (SRSA) and the contents of total phenols, total flavonoids, total flavanols and total anthocyanins were determined. The results showed that the contents of phenolic compounds and the levels of antioxidant activity in the wine samples greatly varied with cultivar and environmental factors of vine growth. The contents of phenolic compounds and antioxidant activities in Cabernet Sauvignon and Merlot wines from the Yuquanying region of Ningxia were significantly higher than other three regions, followed by the wines from Shacheng region of Hebei, and these parameters were the lowest in Cabernet Sauvignon and Merlot wines from the Changli regions of Hebei and Xiangning region of Shanxi. Taken together, a close relationship between phenolic subclasses and antioxidant activity was observed for the wine samples. Moreover, there were significant discrepancies in the individual phenolic composition and content of four regional Cabernet Sauvignon and Merlot wines, among which the individual phenolic compounds (catechin, epicatechin, cinnamic acid, quercetin-3-O-glucuronide, quercetin-3-O-glucoside, laricitrin-3-O-glucoside and isorhamnetin-3-O-glucoside) revealed a significant correlation (p < 0.05) with the antioxidant capacity in present study, especially for catechin and epicatechin.

In order to elucidate the aroma components of wine produced in the Loess Plateau region of China, volatile compounds of young wines from Cabernet Sauvignon, Cabernet Gernischet and Chardonnay varieties grown in the new ecological region were investigated for the first time in this research. Among the volatile compounds analyzed by HS-SPME with GC-MS, a total of 45, 44 and 42 volatile compounds were identified and quantified in Cabernet Sauvignon, Cabernet Gernischet and Chardonnay wines, respectively. In the volatiles detected, alcohols formed the most abundant group in the aroma compounds of the three wines, followed by esters and fatty acids. According to their odor active values (OAVs), 18 volatile compounds were always present in the three wines at concentrations higher than their threshold values, but ethyl octanoate, ethyl hexanoate, and isoamyl acetate were found to jointly contribute to 92.9%, 93.3%, and 98.7%, of the global aroma of Cabernet Sauvignon, Cabernet Gernischet and Chardonnay wines, respectively. These odorants are associated with “fruity’’ and ‘‘ripe fruit’’ odor descriptors.

Calcium is a vital trace element for the human body, and its deficiency can result in a range of pathological conditions, including rickets and osteoporosis. Despite the numerous types of calcium supplements currently available on the market, these products are afflicted with a number of inherent deficiencies, such as low calcium content, poor aqueous solubility, and low human absorption rate. Many microorganisms, particularly beneficial microorganisms, including edible fungi, lactic acid bacteria, and yeast, are capable of absorbing and enriching calcium, a phenomenon that has been widely documented. This opens the door to the potential utilization of microorganisms as novel calcium enrichment carriers. However, the investigation of calcium-rich foods from microorganisms still faces many obstacles, including a poor understanding of calcium metabolic pathways in microorganisms, a relatively low calcium enrichment rate, and the slow growth of strains. Therefore, in order to promote the development of calcium-rich products from microorganisms, this paper provides an overview of the impacts of calcium addition on strain growth, calcium enrichment rate, antioxidant system, and secondary metabolite production. Additionally, it highlights calcium transport and enrichment mechanisms in microorganism cells and offers a detailed account of the progress made on calcium-binding proteins, calcium transport pathways, and calcium storage and release. This paper offers insights for further research on the relevant calcium enrichment in microorganism cells.

Background: Sargentodoxae Caulis (SC) is the vine stem of Sargentodoxa Cuneata (Oliv.) Rehd. & E. H. Wilson in C. S. Sargent, and it in traditional Chinese medicine has been known for promoting blood circulation and removing blood stasis as recorded in the ancient book "Illustrated Classics of Materia Medica". It has been used effectively to treat blood stasis too in modern clinical practice. However, the anti-hyperlipidemia effect of SC is not fully understood. This paper aims at exploring the use of SC stems to improve the balance of blood lipids in the body, and its new role in treating hyperlipidemia. Methods: The effects of SC extract on hyperlipidemia were explored by combining lipidomics and gut microbiota. Secondly, we explored the potential mechanism of SC in treating hyperlipidemia by pathway analysis. Results: The results showed that the stem extract of SC could restore the physiological and biochemical indices of hyperlipidemia in mice, as well as repair the morphological and structural damage to tissues. Compared to the Model group, the SC extract significantly reduced the liver index, epididymal fat index, and Lee's index. It also significantly decreased serum levels of total cholesterol, triglycerides, low-density lipoprotein cholesterol, peroxisome proliferator-activated receptor gamma (PPAR-y), D-lactate, and free fatty acids, while significantly increasing the relative content of peroxisome proliferator-activated receptor alpha (PPAR-a). These changes were statistically significant. Non-targeted lipidomics, based on LC-MS, were utilized to investigate the lipid metabolism characteristics in serum, liver, and epididymal fat of the subjects. It was observed that, compared to the blank group, the Model group exhibited significant changes primarily in glycerol lipids and glycerophospholipids. The treatment group also displayed alterations in these lipids. A total of 38, 81, and 27 differential lipids were identified in serum, liver, and epididymal fat samples, respectively. Among these, 14 common differential lipids were found in both serum and liver samples, and their KEGG enrichment pathways were largely consistent. Among them, the sphingolipid signaling pathway and the glycerophospholipid metabolic pathway were identified as key metabolic pathways that were regulated. Our gut microbiota analysis revealed that SC diminishes the abundance of Actinobacteria by altering the cecal flora in mice. Conclusion: This alteration leads to the downregulation of genes involved in triglyceride metabolism, which in turn changes lipid processing and reduces triglyceride levels. Consequently, SC effectively combats hyperlipidemia. Notably, SC impacts key metabolic pathways, including the sphingolipid signaling and glycerophospholipid metabolism. These findings underscore SC's therapeutic potential, positioning it as a promising alternative for reducing the health risks associated with hyperlipidemia. [ABSTRACT FROM AUTHOR]

The experiment was to study the effects of dietary isochlorogenic acid (ICGA) on early growth performance, intestinal structure, immune performance, and microbial diversity of broilers. 400 one-day-old Kebao broilers, half in male and half female, were randomly divided into five groups with eight replicates in each group and 10 chickens in each replicate. Each group was fed with basal diet (control group), basal diet + 500 mg/kg ICGA (T1 group), basal diet + 1 000 mg/kg ICGA (T2 group), basal diet + 2 000 mg/kg ICGA (T3 group), and basal diet + 3 000 mg/kg ICGA (T4 group). The trial period was 21 days. The results showed that the average daily feed intake (ADFI), average daily gain (ADG), and feed-to-weight ratio (F/G) were not significantly different among the groups (P>0.05). The apparent metabolic rate of crude protein (CP) in T3 group and T4 group was significantly higher than that in control group and T2 group (P<0.05), and the apparent metabolic rate of calcium (Ca) in all experimental groups was extremely higher than that in the control group (P<0.01). The ileal pH value of T3 group was significantly lower than that of other groups (P<0.05). Serum complement C3 content of broilers in each experimental group was significantly higher than that in the control group (P<0.05), and serum immunoglobulin G (IgG) and immunoglobulin M (IgM) content of broilers in T3 group were significantly higher than that in other groups (P<0.05). The villus height of T3 group was significantly higher than that of the control group and T1 group (P<0.05), and the villus-saphenous ratio of T3 group was significantly higher than that of the control group, T1 group, and T2 group (P<0.05). Subdoligranulum&lowbar;variabile in T2 group and T3 group was significantly higher than that in control group and T1 group (P<0.05). Subdoligranulum&lowbar;variabile in T2 group was extremely higher than that in the control group (P<0.01). The study indicates that the nutrient apparent metabolic rate, immune performance, intestinal structure, and intestinal flora were improved by adding ICGA in the diet. The appropriate level of ICGA in the diet of broilers is 2 000 mg/kg. [ABSTRACT FROM AUTHOR]

The purpose of this study was to study and analyze the composition and content of routine nutrients, amino acids, fatty acids, and mineral elements in muscle of three cultured populations of Cipangopaludina cathayensis, so as to provide a reference for the development and utilization of Cipangopaludina cathayensis germplasm resources. A total of 180 Cipangopaludina cathayensis with an average weight of (32.12±0.17) g were randomly divided into three groups with 60 Cipangopaludina cathayensis in each group. After shelling, the muscles were taken to test their nutritional components. The results showed that the crude protein, total amino acids, essential amino acids, and delicious amino acids in muscle of Luchuan County population were significantly higher than those of other populations (P<0.05). The amino acid score, chemical score, and essential amino acid index of Liujiang population were the highest. The contentrations of unsaturated fatty acids and polyunsaturated fatty acids in muscle of Luchuan County population were significantly higher than those of other populations, and the atherosclerosis index (IA) and thrombosis index (IT) were lower than those of other populations (P<0.05). The ratio of sigma-n-3/sigma-n-6PUFA of the three populations was in line with the recommended value of FAO/WHO for human diet (0.1~0.2). The contentrations of P and Ca in muscle of Rongshui County population were significantly higher than those of other populations (P<0.05). The study indicates that the muscle protein content of the three cultured populations is higher, the fat content is lower, and the delicious amino acids and unsaturated fatty acids are higher. The nutritional value of the muscle of Luchuan County population are better than those of other populations. [ABSTRACT FROM AUTHOR]

The purpose of the study was to study the effects of different fiber sources feeds on the growth performance, slaughter performance, immune organ development, and antioxidant capacity of rabbits. In the study, 96 healthy 35-dayold Ira meat rabbits with similar weight were randomly divided into four groups, with eight replicates in each group and three rabbits in each replicate. The four experimental groups used soybean husk, rice straw, peanut seedling, and alfalfa as the only fiber source to prepare full-price diets. The pre-test period was seven days, and the formal test period was 30 days. The results showed that the final weight and average daily gain of soybean husk group, peanut seedling group, and alfalfa group were significantly higher than those of the straw group (P<0.05), and the average daily feed intake of the straw group, peanut seedling group, and alfalfa group was significantly higher than that of soybean husk group (P<0.05). The live weight before slaughter of soybean husk group, peanut seedling group, and alfalfa group was significantly higher than that of straw group (P<0.05), and the carcass weight, semi eviscerated weight, and eviscerated weight of peanut seedling group and alfalfa group were significantly higher than those of straw group (P<0.05). The liver index of alfalfa group was significantly higher than that of other groups (P<0.05), and the index of round sac was significantly higher than that of soybean husk group and peanut seedling group (P<0.05). The serum glutathione peroxidase (GSH-Px) activity in the soybean husk group was significantly higher than that in the other groups (P<0.05). The study indicates that alfalfa has the best comprehensive performance as a fiber source for rabbit diet, and peanut seedlings is second only to alfalfa and better than soybean husk and straw. [ABSTRACT FROM AUTHOR]

The viability and high survival rate of probiotics through human gastrointestinal tract are very important to the host health. The present research was investigated to explicate the influence of encapsulation and wall materials on the survival of Enterococcus faecalis HZNU S1. Purposely, the microbeads were prepared using sodium alginate (SA) and flaxseed milk (FM) by extrusion method. The viability of investigated probiotics was accessed in simulated gastric juice (SGJ). Free cells exhibited a poor survival rate in SGJ. However, encapsulation improved the probiotic viability in the same circumstance. Encapsulated probiotics exhibited higher viability when they were exposed to pH 2.5 SGJ and 1.0 and 2.0% bile salt solutions. Furthermore, encapsulation could improve the storage stability of probiotics. The viable number of encapsulated cells was 10.01 Log CFU/g at 0 day and decreased to 9.6 Log CFU/g (4 °C) and 9.2 Log CFU/g (25 °C) after 8 days. Full encapsulated cells could be liberated after the microbeads were exposed to simulated intestine juice (SIJ) within 120 min. This study indicates that FM-SA microbeads can be suggested as good agents for encapsulating probiotics. [ABSTRACT FROM AUTHOR]

Percussive drilling shows excellent potential for promoting the rate of penetration (ROP) in drilling hard formations. Polycrystalline diamond compact (PDC) bits account for most of the footage drilled in the oil and gas fields. To reveal the rock failure mechanisms under the impact load by PDC bits, a series of drop tests with a single PDC cutter were conducted to four kinds of rocks at different back rake angles, drop heights, drop mass, and drop times. Then the morphology characteristics of the craters were obtained and quantified by using a three-dimensional profilometer. The fracture micrographs can be observed by using scanning electron microscope (SEM). The distribution and propagation process of subsurface cracks were captured in rock-like silica glass by a high-speed photography system. The results can indicate that percussive drilling has a higher efficiency and ROP when the rock fractures in brittle mode. The failure mode of rock is related with the type of rock, the impact speed, and the back rake angle of the cutter. Both the penetration depth and fragmentation volume get the maximum values at a back rake angle of about 45°. Increasing the weight and speed of falling hammer is beneficial to improving the rock breaking effects and efficiency. The subsurface cracks under the impact load by a single PDC cutter is shaped like a clamshell, and its size is much larger than the crater volume. These findings can help to shed light on the rock failure mechanisms under the impact of load by a single PDC cutter and provide a theoretical explanation for better field application of percussive drilling. [ABSTRACT FROM AUTHOR]

Relating supramolecular helices to the spontaneous resolution that generates conglomerate crystals is meaningful to the production of enantiopure compounds and to the understanding of natural homochirality as well. While homochiral elongation is favored along the axis of 1D supramolecular helical chains, conglomerate crystallization requires a 3D homochiral framework. This inspires us to explore new avenues to the spontaneous resolution through the formation of multiple supramolecular helices during crystallization. This Concept outlines and reviews multiple supramolecular helices found in the conglomerate crystals, i. e. three supramolecular helices along one crystallographic axis and two or three supramolecular helices along different crystallographic axes, followed by our observations of homochiral elongation of the helicity of the helical building blocks, the azapeptides, during the formation of supramolecular helices, as well as the spontaneous resolution of amino acid alanine that is made into a helical azapeptide derivative via the formation of supramolecular helices along two different crystallographic axes. [ABSTRACT FROM AUTHOR]

The study was to investigate the effect of lignin polyphenols and copper-zinc cross-linking substance combined supplementation on growth performance, immunity and copper, zinc deposition of weaned piglets. Ninety-six healthy weaned piglets (Duroc x Landrace x Yorkshire) with similar body weight were selected and randomly divided into three groups, with four replicates in each group and eight pigs in each replicate. The control group piglets were fed with basal diet + 2 kg/t zinc oxide + 100 g/t chlortetracycline + 40 g/t colistin, T1 group piglets were fed with basal diet + 1 kg/t lignin polyphenols + 700 g/t copper-zinc cross-linking substance, T2 group piglets were fed with basal diet + 2 kg/t lignin polyphenols + 700 g/t copper-zinc cross-linking substance. The pre-feeding period lasted for 7 d, the formal experiment lasted for 28 d. The results showed that compared with control group, the average daily feed intake and average daily gain of piglets in T2 group were slightly increased ( P>0.05), the average daily feed intake of T1 group was significantly decreased (P<0.05). There was no significant difference in feed to gain ratio and diarrhea rate of piglets among all groups (P>0.05). Compared with control group, the content of IFN-γ in serum of piglets in T1 group was significantly decreased (P<0.05). Compared with control group and T1 group, the content of C4 in serum of piglets in T2 group was significantly increased and significantly higher than that in T1 group ( P<0.05), the content of DLA in serum of piglets in T2 group was significantly decreased and significantly lower than that in T1 group (P<0.05). Compared with control group, the content of zinc in serum and feces of piglets in T1 group and T2 group were significantly decreased ( P<0.05). The study indicates that the combined addition of 2 kg/t lignin polyphenols and 700 g/t copper-zinc cross-linking substance to weaned piglet diet to replace the combination of high zinc and antibiotics can maintain the normal growth performance of weaned piglets, improve immunity, significantly reduce the excretion of zinc in the feces. [ABSTRACT FROM AUTHOR]