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Soil moisture is an important factor that affects terrestrial ecosystems and biological growth and development, and water deficit is one of the major environmental factors threatening vegetation restoration on the Loess Plateau. The purpose was to identify the change in the soil water deficit characteristics from grassland to forestland on the Loess Plateau. In this study, we measured the soil water storage and deficit in abandoned grassland, shrubland, pioneer forestland and climax forestland along with vegetation succession in situ monitor. The results showed that the soil water content and the soil water storage with natural vegetation recovery from the abandoned grassland to shrubland and forestland showed a gradual declining trend. While on the contrary, the soil water deficit was increasing during succession, it was more severe in the deep soil than in the shallow soil layers. And the soil water deficit in July and September of the rainy season as well as that the vigorous growing period of plants was more serious than that in May and November, which are in the non-rainy season on the Chinese Loess Plateau. The vegetation types and soil depth were the key factors affecting the soil water deficiency status in the process of vegetation succession. Water-saving measures should be taken during the vigorous growing period of plants especially for those forest with natural restoration ages >50a on the Loess Plateau. The results could have great potential in the sustainable development of forestry and provide a theoretical basis for effective water management and reasonable vegetation restoration in semiarid loess regions.

Auxin is throughout the entire life process of plants and is involved in the crosstalk with other hormones, yet its role in apple disease resistance remains unclear. In this study, we investigated the function of auxin/indole-3-acetic acid (IAA) gene MdIAA24 overexpression in enhancing apple resistance to Glomerella leaf spot (GLS) caused by Colletotrichum fructicola (Cf). Analysis revealed that, upon Cf infection, 35S::MdIAA24 plants exhibited enhanced superoxide dismutase (SOD) and peroxidase (POD) activity, as well as a greater amount of glutathione (reduced form) and ascorbic acid accumulation, resulting in less H2O2 and superoxide anion (O2.−) in apple leaves. Furthermore, 35S::MdIAA24 plants produced more protocatechuic acid, proanthocyanidins B1, proanthocyanidins B2 and chlorogenic acid when infected with Cf. Following Cf infection, 35S::MdIAA24 plants presented lower levels of IAA and jasmonic acid (JA), but higher levels of salicylic acid (SA), along with the expression of related genes. The overexpression of MdIAA24 was observed to enhance the activity of chitinase and β-1,3-glucanase in Cf-infected leaves. The results indicated the ability of MdIAA24 to regulate the crosstalk between IAA, JA and SA, and to improve reactive oxygen species (ROS) scavenging and defense-related enzymes activity. This jointly contributed to GLS resistance in apple.

The selection of suitable tree species and the reasonable allocation of planting areas are important measures for improving soil quality. To evaluate the soil quality (SQ) and its driving factors of Pinus tabuliformis forests in loess hilly areas where forestry ecological projects, such as returning farmland to forest (grass), have been implemented, this study selected P. tabuliformis forests with different restoration years (1a, 6a, 11a, 18a, and 22a) in Wuqi County and used grassland before afforestation (PRG) and abandoned grassland (AG) with 22 years as controls. In this study, soil physicochemical indices, soil fauna indices, and herbaceous plant indices obtained via principal component analysis were used to establish a soil quality evaluation model via the fuzzy comprehensive evaluation method to comprehensively evaluate SQ. Structural equation modeling (SEM) was used to identify the key factors affecting the SQ of P. tabuliformis forests. The goal was to create a model that could effectively evaluate the SQ while considering all relevant factors. The findings of the study showed that: (1) by performing a principal component analysis on the 27 indicator factors, the first six principal components had eigenvalues > 1, and the cumulative contribution rate was 90.028%, effectively encompassing the information of the original variables. (2) The highest soil quality index (SQI) was 0.592 (p < 0.05) in the restored 6a P. tabuliformis forest, whereas the lowest SQI was 0.323 in the restored 1a P. tabuliformis forest. As the number of years of restoration increased, the SQ of the P. tabuliformis plantation forest progressively approached that of the long-term abandoned grassland, with only a 1.8% difference after 22 years of restoration. The SQI of the P. tabuliformis woodland in restored 6a was 83% higher than that of 1a, and following 6a of restoration, the SQI showed a decreasing trend with increasing restoration years. Nevertheless, the SQI increased by >52% compared with the early stage of restoration (1a) and by 31% compared with the grassland before afforestation (PRG). (3) SEM revealed that the SQ of P. tabuliformis forest land was mainly driven by soil physical and herbaceous plant indicators, and soil fauna indicators and restoration years had a negative effect on the evolution of SQ in P. tabuliformis forests. The driving factors of P. tabuliformis forests of different restoration years were different, and with the increase in restoration years, the effects of soil fauna and herbaceous plant indicators on the SQ of P. tabuliformis plantation forests showed an overall upward trend.

Key Clinical Message We report a young man with isolated elevated AST. He had no other evidence of liver or other related diseases. All the tests and examination reports were negative. The final diagnosis of macro‐AST was confirmed by PEG precipitation tests. Abstract Elevated liver enzymes, such as alanine aminotransferase (ALT) and aspartate aminotransferase (AST), may commonly indicate liver injury. However, macro‐AST is generally a benign condition that may be considered as pathologic by clinicians. A young man with isolated elevated AST for more than 10 years who have taken extensive tests and examinations was diagnosed with macro‐AST in our article. Thus, in patients with isolated AST‐elevation, polyethylene glycol (PEG) precipitation test was recommended to test whether macro‐AST could be diagnosed.

Flooding in the United States is projected to become about 8% more severe in a high-emissions scenario by the end of the century based on simulations with a convection-permitting climate model.

The selection of suitable tree species and the reasonable allocation of planting areas are important measures for improving soil quality. This study aimed to investigate the characteristics of typical vegetation type soil quality differences and their dominant factors in loess hilly–gully areas after returning farmland to the forest (grassland). The soil quality status and dominant factors of arbors, shrubs and grasslands in the study area were comprehensively analyzed using the soil quality index (SQI) and structural equation modeling (SEM). The results showed the following: (1) In the study area, the shrub forest had a high capacity for air permeability, water retention and nitrogen fixation. (2) The soil quality of the three vegetation types improved with increasing precipitation, and the soil quality indicator of shrubs was the highest, indicating a better soil quality improvement. However, the soil quality of the arbors and grasslands showed a greater percentage increase. In the precipitation range of 400–410 mm, the soil quality of shrub forests was significantly higher than that of arbors and grasslands. (3) Structural equation modeling analysis indicated that precipitation, vegetation and soil factors are closely related to soil quality. Further analysis showed that soil bulk density, porosity, capillary water-holding capacity, soil organic carbon and total phosphorus were the dominant factors affecting the soil quality in the study area. The purpose of this study was to evaluate quantitatively the soil quality after different vegetation types under different precipitation gradients, to clarify the variation trend of soil quality at different vegetation types with different precipitation gradients and to provide a scientific basis and data support for the quantitative evaluation of vegetation restoration and selection of tree species and vegetation configuration within different precipitation gradients in loess hilly and gully regions in the future.

The driving factors affecting soil quality were identified to evaluate the effect of vegetation on soil quality in coal mine reclamation areas with various restoration durations. This study used Hippophae rhamnoides subsp.sinensis Rousi with different reclamation durations (3, 4, 5, 6, and 7 years) in the abandoned land area of the Juxinlong coal mine in Ordos as the research subject. Artificial and abandoned grasslands were selected as the study’s controls. A soil quality evaluation model was constructed to assess the soil quality in the reclamation area. A structural equation model was used to thoroughly analyze the driving factors affecting soil quality in the study area. The findings show that: (1) Reclamation duration significantly affected the physicochemical characteristics of the soil. As the reclamation duration increased, soil nutrients such as organic carbon accumulated while the bulk density index (BD) decreased. (2) The soil quality index of Hippophae rhamnoides forest land in China was the highest after 6 years of reclamation. The Hippophae rhamnoides forest land with the lowest soil quality index after 4 years of reclamation differed significantly from that after 6 years (p < 0.05). The soil quality index (SQI) of 6a (years) significantly increased by 67.44% compared to 4a. (3) By constructing a structural equation model, it was found that physical indicators (saturated water content and silt) and reclamation durations were the main drivers of soil quality. SQI had a strong interaction with organic matter (OM) and different restoration durations. The findings of this study will serve as important guidelines for future quantitative evaluation of soil quality following land reclamation and management during the ecological restoration process.

Choosing economically important trees and establishing planting patterns can improve soil quality in economic forests. To clarify the soil quality status of the main economic forest land distributed in northern Shaanxi, the research object in this study was jujube and apple economic forests, and the control was grassland. By evaluating 17 soil indicators, the minimum data set (MDS) and structural equation model (SEM) were used to analyze the soil quality status and its dominant factors under different economic forests and land preparation methods. The results showed that (1) compared with grassland, the economic forest has a certain improvement and promotion in soil’s properties, mainly in the water-holding capacity and available nutrients. Compared to the undisturbed slope, the level bench had better physical and chemical properties. (2) Six indicators were identified as the minimum data set for assessing soil quality, including the soil organic carbon, saturated water content, bulk density, alkaline nitrogen, sand, and total capillary porosity. In addition, structural equation model analysis showed that the soil organic carbon, saturated water content, alkaline nitrogen, and capillary porosity were the dominant factors affecting soil quality in the study area. (3) Jujube trees exhibited the highest soil quality and the best restoration effect, followed by apple trees, while grassland had the poorest restoration effect. The soil quality of undisturbed slopes under different land preparation methods was lower than that of the level bench land preparation. The outcomes of this study are to provide data support and a theoretical basis for improving soil quality, enhancing ecological benefits, and selecting and managing economic forest species, in the study area and similar regions in the future.

Abstract Changes in land use type can lead to variations in soil water characteristics. The objective of this study was to identify the responses of soil water holding capacity (SWHC) and soil water availability (SWA) to land use type (grassland, shrubland and forestland). The soil water characteristic curve describes the relationship between gravimetric water content and soil suction. We measured the soil water characteristic parameters representing SWHC and SWA, which we derived from soil water characteristic curves, in the 0–50 cm soil layer at sites representing three land use types in the Ziwuling forest region, located in the central part of the Loess Plateau, China. Our results showed that the SWHC was higher at the woodland site than the grassland and shrubland, and there was no significant difference between the latter two sites, the trend of SWA was similar to the SWHC. From grassland to woodland, the soil physical properties in the 0–50 cm soil layer partially improved, BD was significantly higher at the grassland site than at the shrubland and woodland sites, the clay and silt contents decreased significantly from grassland to shrubland to woodland and sand content showed the opposite pattern, the soil porosity was higher in the shrubland and woodland than that in the grassland, the soil physical properties across the 0–50 cm soil layer improved. Soil texture, porosity and bulk density were the key factors affecting SWHC and SWA. The results of this study provide insight into the effects of vegetation restoration on local hydrological resources and can inform soil water management and land use planning on the Chinese Loess Plateau.

Quercetin 3-O-(6″-O-E-caffeoyl)-β-D-glucopyranoside is a flavonoid compound produced by various plants with reported antiprotozoal potential against E. histolytica and G. lamblia; however, its effects on skin pigment regulation have not been studied in detail. In this investigation, we discovered that quercetin 3-O-(6″-O-E-caffeoyl)—D-glucopyranoside (coded as CC7) demonstrated a more increased melanogenesis effect in B16 cells. CC7 exhibited no cytotoxicity or effective stimulating melanin content or intracellular tyrosinase activity. This melanogenic-promoting effect was accompanied by activated expression levels of microphthalmia-associated transcription factor (MITF), a key melanogenic regulatory factor, melanogenic enzymes, and tyrosinase (TYR) and tyrosinase-related protein-1 (TRP-1) and 2 (TRP-2) in the CC7-treated cells. Mechanistically, we found that CC7 exerted melanogenic effects by upregulating the phosphorylation of stress-regulated protein kinase (p38) and c-Jun N-terminal kinase (JNK). Moreover, the CC7 upregulation of phosphor-protein kinase B (Akt) and Glycogen synthase kinase-3 beta (GSK-3β) increased the content of β-catenin in the cell cytoplasm, and subsequently, it translocated into the nucleus, resulting in melanogenesis. Specific inhibitors of P38, JNK, and Akt validated that CC7 promotes melanin synthesis and tyrosinase activity by regulating the GSK3β/β-catenin signaling pathways. Our results support that the CC7 regulation of melanogenesis involves MAPKs and Akt/GSK3β/β-catenin signaling pathways.

Changing electrical environments can influence the performance of herbivorous insects and adversely affect their control strategies. The diamondback moth, Plutella xylostella (L.), is a pest that devastates cruciferous vegetables. An age–stage, two-sex life table of P. xylostella over multiple generations was established to describe the effect of varying high-voltage electrostatic field (HVEF) exposure on their performance after the age-cohort eggs were exposed to HVEF at an intensity of 5.0 kV/cm for different durations. The results show that direct HVEF exposure adversely affected the population dynamics parameters of P. xylostella over multiple generations. In particular, the net reproduction rate, intrinsic natural increase rate, and finite increase rate of the P. xylostella population significantly decreased in the third and fifth generations under HVEF exposure for 10 min, while the mean generation time and doubling time significantly increased. Similarly, HVEF exposure for 10 min rapidly reduced the survival rate of adult P. xylostella in the first generation, and subsequently, it declined evenly and slowly. Meanwhile, the fecundity parameters of P. xylostella revealed that HVEF exposure for 10 min had the strongest inhibition effect on reproduction over five consecutive generations. In addition, HVEF exposure significantly increased the superoxide dismutase activity to produce extra hydrogen peroxide; however, increased catalase and peroxidase activity or reduced peroxidase activity triggered the accumulation of malondialdehyde in instar P. xylostella, especially after 10 min of treatment. The present findings provide experimental evidence and a theoretical basis for developing control strategies for P. xylostella under new HVEF environments.

Carum carvi L. belongs to the Apiaceae family and is widely used as a vegetable, food spice, preservative, and herbal medicine. This study investigated the impact of essential oil extracted from Carum carvi L. seeds (CEO) on methicillin-resistant Staphylococcus aureus (MRSA) and its possible action mechanism. The dominant chemical components of CEO determined by GC-MS were carvone and limonene. It was observed that CEO had a considerable inhibitory effect against the growth of planktonic bacteria and biofilm in MRSA cells. Untargeted metabolomics based on GC-Q-TOF-MS was used to analyze the possible mechanism of the interaction of MRSA with CEO. It was determined that there were 63 different metabolites based on fold change values greater than 1.5 or less than 1.5, p < 0.05, VIP > 1, which demonstrated amino acid metabolism in MRSA was significantly affected by CEO. In conclusion, CEO has a potent antimicrobial property and has promising potential for use in food and drugs.

Abstract Background Soil salinity is a critical threat to global agriculture. In plants, the accumulation of xanthine activates xanthine dehydrogenase (XDH), which catalyses the oxidation/conversion of xanthine to uric acid to remove excess reactive oxygen species (ROS). The nucleobase-ascorbate transporter (NAT) family is also known as the nucleobase-cation symporter (NCS) or AzgA-like family. NAT is known to transport xanthine and uric acid in plants. The expression of MdNAT is influenced by salinity stress in apple. Results In this study, we discovered that exogenous application of xanthine and uric acid enhanced the resistance of apple plants to salinity stress. In addition, MdNAT7 overexpression transgenic apple plants showed enhanced xanthine and uric acid concentrations and improved tolerance to salinity stress compared with nontransgenic plants, while opposite phenotypes were observed for MdNAT7 RNAi plants. These differences were probably due to the enhancement or impairment of ROS scavenging and ion homeostasis abilities. Conclusion Our results demonstrate that xanthine and uric acid have potential uses in salt stress alleviation, and MdNAT7 can be utilized as a candidate gene to engineer resistance to salt stress in plants.

Background: To elucidate the potential biological function of hsa_circ_0062270 in the malignant process of melanoma and its potential target.Methods: Quantitative real-time polymerase chain reaction (qRT-PCR) was conducted to examine relative level of hsa_circ_0062270 in melanoma tissues and normal skin tissues. The diagnostic and prognostic potentials of hsa_circ_0062270 in melanoma were evaluated. The regulatory effect of hsa_circ_0062270 on the expression of linear transcript Cell division cycle protein 45 (CDC45) was also examined.Results: Hsa_circ_0062270 was up-regulated in melanoma samples and cell lines, which displayed certain diagnostic and prognostic potentials in melanoma. Inhibition of hsa_circ_0062270 attenuated the proliferative, migratory and invasive functions. Hsa_circ_0062270 could stabilize the expression of linear transcript CDC45, and thus participated in the malignant process of melanoma.Conclusion: Hsa_circ_0062270 promotes proliferative, migratory and invasive functions of melanoma cells via stabilizing the linear transcript CDC45. Hsa_circ_0062270 can be used to diagnosis and treatment of melanoma.

The spatial distribution characteristics of soil organic carbon storage (SOCS) and soil water storage (SWS) and the factors that influence these parameters were compared and analyzed for different economic forests under varying land use practices in the study area with the same abandonment years. The widely distributed abandoned mountain jujube and apple forests at the Qijiashan jujube experimental demonstration base in Yanchuan County were the research field, and grassland was the control. The results show that (1) SOCS and SWS accumulated abundantly in the deep layer (below 100 cm) compared to the highest layer, accounting for 60.63% and 64.63%. (2) After abandonment, the SOCS and SWS were different across vegetation types and under different land preparation methods. In the study area, the SWS showed a comparative advantage compared to the SOCS. The trade-off for different vegetation types suggests that it was the highest for grassland (0.39), while the lowest for jujube (0.16). Under different land preparation methods, the RMSE values of the level terrace grassland and undisturbed slope with apple trees were the highest, while those of jujube trees were the lowest. (3) Environmental factors exerted a certain influence on different vegetation types and varying land preparation methods after abandonment. Apart from the interaction between SOCS and SWS, chemical indicators showed the greatest impact on the abandoned grassland and the SOCS of level terraces.

Cadmium (Cd), a phytotoxic heavy metal accumulated in plants and fruits, has significant adverse effects on plant growth and development as well as human health. In particular, Cd pollution has become a serious agricultural issue in recent years. Apple is one of the most popular fruits consumed at the global scale. Improving apple Cd resistance via reductions in Cd absorption can benefit apple tree growth and ensure fruit safety. In this study, we determined that, under the 200 μM Cd treatment, 35S::MdIAA24 apple plants exhibited more biomass and less Cd accumulation in the tested tissues compared to wild type (WT). Furthermore, the 35S::MdIAA24 apple plants demonstrated more favorable photosynthesis characteristics, less reactive oxygen species (ROS) and a greater amount of active antioxidant enzymes under the Cd condition than WT. The expression levels of the Cd uptake genes were observed to be lower in the 35S::MdIAA24 apple plants compared with those of the WT under the Cd treatment. The results highlight the ability of the overexpression of MdIAA24 to enhance apple Cd resistance by improving antioxidant capacity and reducing Cd absorption.

This paper proposes to improve the output performance of a piezoelectric pump by matching the resonant frequency of the resonator to the optimal operating mode of bridge-type polydimethylsiloxane (PDMS) check valves. Simulation analyses reveal that the side-curling mode of the PDMS valve is conducive to liquid flow and exhibits a faster frequency response compared with the first bending mode. The first bending resonant frequency of a beam-type piezoelectric resonator was tuned close to the side-curling mode of the PDMS valve by adjusting the weight of two mass blocks installed on both ends of the resonator, so that both the resonator and the valve could work at their best conditions. Experiments were conducted on a detachable prototype piezoelectric pump using PDMS valves with three different lengths. The results confirm that the peak flowrate at the resonant point of the pump reaches its maximum when the resonant frequencies between the resonator and the valve are matched. Maximum peak flowrates of 88 mL/min, 72 mL/min and 70 mL/min were achieved at 722 Hz, 761 Hz and 789 Hz, respectively, for diaphragm pumps using five-, four- and three-inlet-hole PDMS valves, under a driving voltage of 300 Vpp.

Niche theory is significant for understanding the function of community structure, interspecific relationships, and community dynamic succession. However, there are few studies on the soil animal niche in returning farmland to forest areas on the Loess Plateau, making it challenging to comprehend the utilization of soil animal resources, the stability of the local community, and the succession process in the areas. Therefore, this study collected soil animals in five typical vegetation types: Robinia pseudoacacia (R), Hippophae rhamnoides (H), Populus simonii (P), Pinus tabulaeformis (T), and Armeniaca sibirica x Hippophae rhamnoides (M), with abandoned grassland (G) used as a control group. Then, the number of soil animal taxa, individuals, diversity, and niche were sampled and examined in the study areas during the four seasons of spring, summer, autumn, and winter using the manual sorting method and the Tullgren method. The results revealed that 3872 soil animals from 3 Phyla, 8 Classes, 22 Orders, and 49 Families were captured in the study areas. The dominant groups of soil macrofauna were Diptera larvae, Julidae, and Formicidae, and the dominant groups of meso–micro soil fauna were Oribatida, Protospira, and Collembola juveniles. Soil animals have rich nutritional function groups, with the most saprophytic soil animal groups. The individual density and taxa number of soil animals in G were lower than other vegetation on the whole. H, M, and P had a higher Shannon–Winner index than the other vegetation. Seasonal changes had different effects on macro and meso–micro soil fauna. The diversity of soil macrofauna is higher in spring and summer, and that of meso–micro soil fauna is higher in autumn and winter. Oribatida, Diptera Larvae, and Formicidae had a large niche width in the main taxa of soil animals, with universal adaptability to the environment. Cicadellidae and Culicidae had narrow niche widths and were highly dependent on resources and the environment. There were 67 pairs of highly overlapped (Oik > 0.8) taxa of soil animals and 56 pairs of moderately overlapped (0.6 < Oik ≤ 0.8) taxa, accounting for 80.39% of the total number of taxa. Soil animals had high commonality in resource utilization, intense competition, and poor community stability. As a result, we can conclude that the soil animal community in the study areas was in the stage of succession.

In a complete organic ecosystem restoration in mining areas, soil and vegetation complement and influence each other. It is of great significance to evaluate the ecological restoration effect on and ecosystem stability of the mining area, with the coupling and coordinating relationship between herb community and soil physicochemical properties after land reclamation. Therefore, this study takes Juxinlong Coal Mine in Dongsheng District of Ordos City, Inner Mongolia Autonomous Region as the study area. The understory herbaceous plant community and soil factors with restoration time of 3 to 7 years were selected as the research objects. In addition, artificial grassland and natural restoration grassland were used as controls to investigate the species composition of herbaceous communities and soil physicochemical properties in different sites. The grey relational coupling model was adopted not only to study the relationship between herb community and soil factors but also to explore the coupling mechanism between herb community and soils’ physicochemical properties. The results included: (1) 51 herbaceous plants were investigated in the study area, among which Gramineae, Compositae, Leguminosae, and Chenopodiaceae were the primary ones, accounting for 70% of the total. (2) With the increase of restoration years, the diversity indices of understory herbaceous plants generally showed an increasing trend, but the diversity indices of understory herbaceous plants with different restoration years was smaller than that of artificial grassland. (3) The results of grey correlation analysis showed that the diversity of herbaceous plant community in the study area was closely related to soils’ available nitrogen and water content. (4) The degree of coupling and coordinating between the diversity of herbaceous plants and soils in the study area presented a trend of first increasing then decreasing during the accumulating restoration years. Among them, the degree of coupling between the diversity of understory herbaceous plants and soil system in the 5-year restoration’s sample plot (0.73) was found to be the highest, which was classified as medium coordination. The lowest coupling degree of herb diversity and soils was identified in the artificial grassland (0.51), which was light incoordination. Therefore, it is suggested that the control of water and nitrogen resources should be strengthened, the herbaceous vegetation should be reasonably selected, and the artificial tending should be carried out in the later stage of understory herbaceous vegetation construction in the study area to better promote the vegetation construction in the mining area.

Vegetation restoration is essential for the stability of the ecological system structure and function in the loess region of North Shaanxi Province. Natural and artificial restoration are the primary modes for vegetation recovery and soil quality improvement in this region. In this study, two adjacent watersheds with similar ecological environment conditions but different restoration modes were selected for research; one watershed is restored naturally (He Gou watershed), and the other is restored artificially (Chai Gou watershed). According to the study of soil stoichiometric characteristics and soil quality after the vegetation restoration in these two watersheds, the results showed: (1) Compared with the natural restoration, artificial restoration was more effective in increasing the content of soil organic carbon and total nitrogen, however, the total phosphorus content of the soil in the natural restoration mode was higher than that in the artificial restoration mode. (2) The ratios of soil C:N, C:P, and N:P showed a decreasing trend with the increase of soil depth at these two restoration modes. (3) In the 0–60 cm soil layer, the soil quality under the artificial restoration mode was better than that of the natural restoration, especially for the soil layer beneath 20 cm. (4) The minimal data set on the soil quality evaluation in the study area included soil organic carbon, capillary water holding quantity, available potassium, soil water content and available phosphorus. It showed a linear relation with the total index data set (y = 0.829x + 0.058, R2 = 0.76) and can reflect the soil quality more sensitively than the total indicator data set.

Abstract Background The FK506-binding proteins (FKBPs) play diverse roles in numerous critical processes for plant growth, development, and abiotic stress responses. However, the FKBP gene family in the important fruit crop apple (Malus × domestica Borkh.) has not been studied as thoroughly as in other species. Our research objective was to investigate the mechanisms by which apple FKBPs enable apple plants to tolerate the effects of abiotic stresses. Results Using bioinformatics-based methods, RT-PCR, and qRT-PCR technologies, we identified 38 FKBP genes and cloned 16 of them in the apple genome. The phylogenetic analysis revealed three major groups within that family. The results from sequence alignments, 3-D structures, phylogenetics, and analyses of conserved domains indicated that apple FKBPs are highly and structurally conserved. Furthermore, genomics structure analysis showed that those genes are also highly and structurally conserved in several other species. Comprehensive qRT-PCR analysis found various expression patterns for MdFKBPs in different tissues and in plant responses to water-deficit and salt stresses. Based on the results from interaction network and co-expression analyses, we determined that the pairing in the MdFKBP62a/MdFKBP65a/b-mediated network is involved in water-deficit and salt-stress signaling, both of which are uniformly up-regulated through interactions with heat shock proteins in apple. Conclusions These results provide new insight for further study of FKBP genes and their functions in abiotic stress response and multiple metabolic and physiological processes in apple.

Abstract Well-ordered TiO2 nanotube arrays (TNTAs) decorated with graphitic carbon nitride (g-C3N4) were fabricated by anodic oxidization and calcination process. First, TNTAs were prepared via the anodic oxidation of Ti foil in glycerol solution containing fluorinion and 20% deionized water. Subsequently, g-C3N4 film was hydrothermally grown on TNTAs via the hydrogen-bonded cyanuric acid melamine supramolecular complex. The results showed that g-C3N4 was successfully decorated on the TNTAs and the g-C3N4/TNTAs served as an efficient and stable photoanode for photoelectrochemical water splitting. The facile deposition method enables the fabrication of efficient and low-cost photoanodes for renewable energy applications.

Auxin is a plant hormone that takes part in a series of developmental and physiological processes. There are three major gene families that play a role in the early response of auxin and auxin/indole-3-acetic acid (Aux/IAA) is one of these. Although the genomic organization and function of Aux/IAA genes have been recognized in reference plants there have only been a few focused studies conducted with non-model crop plants, especially in the woody perennial species. We conducted a genomic census and expression analysis of Aux/IAA genes in the cultivated apple (Malus × domestica Borkh.). The Aux/IAA gene family of the apple genome was identified and analyzed in this study. Phylogenetic analysis showed that MdIAAs could be categorized into nine subfamilies and that these MdIAA proteins contained four whole or partially conserved domains of the MdIAA family. The spatio-specific expression profiles showed that most of the MdIAAs were preferentially expressed in specific tissues. Some of these genes were significantly induced by treatments with one or more abiotic stresses. The overexpression of MdIAA9 in tobacco (Nicotiana tabacum L.) plants significantly increased their tolerance to osmotic stresses. Our cumulative data supports the interactions between abiotic stresses and plant hormones and provides a theoretical basis for the mechanism of Aux/IAA and drought resistance in apples.

The flow in the gap between the reed and the valve seat has a significant influence on the dynamic characteristics of the reed valve used in reciprocating compressors. The fluid–structure interaction (FSI) method is an effective method for studying reciprocating compressors. A three-dimensional FSI model of a reciprocating compressor with a reed valve is established in this paper, which has an important influence on the flow rate characteristic of reciprocating compressors. Furthermore, an experimental investigation is implemented to verify the FSI model. Based on the established FSI model, the pressure distribution on the reed valve surface is identified by varying the height of the suction valve limiter and the rotational speed of the compressor, which has an important effect on the dynamic characteristics of the reed valve. Although the low-pressure region, due to the Bernoulli effect on the surface of the reed, hinders the rapid opening of the valve to some extent, it is obviously beneficial to the timely closure of the valve and increases the volumetric efficiency of the compressor. Moreover, the optimal height of the valve limiter and the appropriate rotational speed of the compressor are obtained.

This study proposes the improvement of the output performance of a resonant piezoelectric pump by adding proof masses to the free ends of the prongs of a U-shaped piezoelectric resonator. Simulation analyses show that the out-of-phase resonant frequency of the developed resonator can be tuned more efficiently within a more compact structure to the optimal operating frequency of the check valves by adjusting the thickness of the proof masses, which ensures that both the resonator and the check valves can operate at the best condition in a piezoelectric pump. A separable prototype piezoelectric pump composed of the proposed resonator and two diaphragm pumps was designed and fabricated with outline dimensions of 30 mm × 37 mm × 54 mm. Experimental results demonstrate remarkable improvements in the output performance and working efficiency of the piezoelectric pump. With the working fluid of liquid water and under a sinusoidal driving voltage of 298.5 Vpp, the miniature pump can achieve the maximum flow rate of 2258.9 mL/min with the highest volume efficiency of 77.1% and power consumption of 2.12 W under zero backpressure at 311/312 Hz, and the highest backpressure of 157.3 kPa under zero flow rate at 383 Hz.

Ethylene plays an important role in stress adaptation and fruit ripening. Acireductone dioxygenase (ARD) is pivotal for ethylene biosynthesis. However, the response of ARD to fruit ripening or cold stress is still unclear. In this study, we identified three members of Malus ARD family, and expression profile analysis revealed that the transcript level of MdARD4 was induced during apple fruit ripening and after apple plants were being treated with cold stress. To investigate its function in cold tolerance and fruit ripening, MdARD4 was ectopically expressed in Solanum lycopersicum cultivar ‘Micro-Tom’, which has been considered as an excellent model plant for the study of fruit ripening. At the cellular level, the MdARD protein expressed throughout Nicotiana benthamiana epidermal cells. Overexpression of MdARD4 in tomato demonstrated that MdARD4 regulates the ethylene and carotenoid signaling pathway, increases ethylene and carotenoid concentrations, and accelerates fruit ripening. Furthermore, MdARD4 increased the antioxidative ability and cold hardiness in tomato. To conclude, MdARD4 may potentially be used in apple breeding to accelerate fruit ripening and increase cold hardiness.

The characteristics of the transcritical CO2 heat pump water heater (HPWH) system are; a lower inlet hot water temperature (Ti-hw) (sometimes this is lower than the water source temperature), and an outlet gas cooler temperature (To-gc) which is affected by the Ti-hw and often lower than the critical temperature. In order to study the effects of the internal heat exchanger (IHX) on the operational performance of the transcritical CO2 HPWH when To-gc is low, a transcritical CO2 water source HPWH experiment platform is established to conduct experimental research and comparative analysis on the operational performance of the transcritical CO2 water source HPWH, with or without IHX. It is found that, if only the coefficient of performance (COP) and heating at the optimal exhaust pressure of the transcritical CO2 water source HPWH were considered, COP and the heating of the non-IHX system would be slightly higher than those of the IHX system at the lower hot water flow and water source temperature, and this increase was not obvious. At the higher hot water flow rate and water source temperature, COP and the heating of the non-IHX system were also higher than those of the IHX system, and the increase was obvious. The experiment results showed that, near the optimal exhaust pressure, the variation range of COP and heating of the IHX system is relatively small, and the system has a relatively high stability.

A linear theory for the electromagnetic properties and interactions of an annular beam-ion channel system in plasma waveguide is presented. The dispersion relations for two families of propagating modes, including the electrostatic and transverse magnetic modes, are derived. The dependencies of the dispersion behavior and interaction for different wave modes on the thickness of the annular beam and betatron oscillation frequency are studied in detail by numerical calculations. The results show that the inner and outer radii of the beam have different influences on propagation properties of the electrostatic and electromagnetic modes with different betatron oscillation parameters. In the weak ion channel situation, the two types of electrostatic waves, that is, space charge and betatron modes, have no interaction with the transverse magnetic modes. However, in the strong ion channel situation, the transverse magnetic modes will have two branches and a low frequency mode emerged as the new branch. In this case, compared with the solid beam case, the betatron modes not only can interact with the high frequency branch at small wavenumber but also can interact with the low frequency branch at large wavenumber.

Chiral separations of five β-adrenergic antagonists (propranolol, esmolol, atenolol, metoprolol, and bisoprolol) were studied by capillary electrophoresis using six cyclodextrins (CDs) as the chiral selectors. Carboxymethylated-β-cyclodextrin (CM-β-CD) exhibited a higher enantioselectivity power compared to the other tested CDs. The influences of the concentration of CM-β-CD, buffer pH, buffer concentration, temperature, and applied voltage were investigated. The good chiral separation of five β-adrenergic antagonists was achieved using 50 mM Tris buffer at pH 4.0 containing 8 mM CM-β-CD with an applied voltage of 24 kV at 20 °C. In order to understand possible chiral recognition mechanisms of these racemates with CM-β-CD, host-guest binding procedures of CM-β-CD and these racemates were studied using the molecular docking software Autodock. The binding free energy was calculated using the Autodock semi-empirical binding free energy function. The results showed that the phenyl or naphthyl ring inserted in the hydrophobic cavity of CM-β-CD and the side chain was found to point out of the cyclodextrin rim. Hydrogen bonding between CM-β-CD and these racemates played an important role in the process of enantionseparation and a model of the hydrogen bonding interaction positions was constructed. The difference in hydrogen bonding formed with the –OH next to the chiral center of the analytes may help to increase chiral discrimination and gave rise to a bigger separation factor. In addition, the longer side chain in the hydrophobic phenyl ring of the enantiomer was not beneficial for enantioseparation and the chiral selectivity factor was found to correspond to the difference in binding free energy.

The NITRATE TRANSPORTER 1/PEPTIDE TRANSPORTER family (NPF) proteins play important roles in moving substrates such as nitrate, peptides, amino acids, dicarboxylates, malate, glucosinolates, indole acetic acid (IAA), abscisic acid (ABA), and jasmonic acid. Although a unified nomenclature of NPF members in plants has been reported, this gene family has not been studied as thoroughly in apple (Malus × domestica Borkh.) as it has in other species. Our objective was to provide general information about apple MdNPFs and analyze the transcriptional responses of some members to different levels of nitrate supplies. We identified 73 of these genes from the apple genome and used phylogenetic analysis to organize them into eight major groups. These apple NPFs are structurally conserved, based on alignment of amino acid sequences and analyses of phylogenetics and conserved domains. Examination of their genomic structures indicated that these genes are highly conserved among other species. We monitored 14 cloned MdNPFs that showed varied expression patterns under different nitrate concentrations and in different tissues. Among them, NPF6.5 was significantly induced by both low and high levels of nitrate. When compared with the wild type, 35S:MdNPF6.5 transgenic apple calli were more tolerant to low-N stress, which demonstrated that this gene confers greater capacity for nitrogen uptake under those conditions. We also analyzed the expression patterns of those 73 genes in various tissues. Our findings benefit future research on this family of genes.

Stress-associated proteins (SAPs) are novel A20/AN1 zinc finger domain-containing proteins that are now favorable targets to improve abiotic stress tolerance in plants. However, the SAP gene family and their biological functions have not been identified in the important fruit crop apple (Malus × domestica Borkh.). We conducted a genome-wide analysis and cloning of this gene family in apple and determined that the overexpression of MdSAP15 enhances drought tolerance in Arabidopsis plants. We identified 30 SAP genes in the apple genome. Phylogenetic analysis revealed two major groups within that family. Results from sequence alignments and analyses of 3D structures, phylogenetics, genomics structure, and conserved domains indicated that apple SAPs are highly and structurally conserved. Comprehensive qRT-PCR analysis found various expression patterns for MdSAPs in different tissues and in response to a water deficit. A transgenic analysis showed that the overexpression of MdSAP15 in transgenic Arabidopsis plants markedly enhanced their tolerance to osmotic and drought stresses. Our results demonstrate that the SAP genes are highly conserved in plant species, and that MdSAP15 can be used as a target gene in genetic engineering approaches to improve drought tolerance.

The effect of the discharge pressure on the performance of the trans-critical CO2 heat pump with a low gas-cooler outlet temperature is experimentally investigated on a test rig of water source heat-pump water heater. The optimal discharge pressure of the trans-critical CO2 heat pump is investigated under different external operation conditions. When the tap-water temperature is low, the characteristic of the S-shape isotherm at the supercritical region has little effect on the occurrence of the optimal discharge pressure; while the mass flow rate of CO2, the suction pressure and the gas-cooler outlet temperature play a significant role in determining the emergence of the optimal discharge pressure. At the optimal discharge pressure, the COP reaches the peak; however, the corresponding heating capacity is still lower than its maximum, which is reached as the discharge pressure is slightly above the optimal discharge pressure. Reducing the tap-water flowrate or increasing the water-source temperature can increase the optimal discharge pressure. The COP is positively dependent on both the tap-water flowrate and the water-source temperature. In addition, the tap-water flowrate has a negligible influence on the maximum heating capacity while increasing the water-source temperature can greatly enhance the heating capacity.

Background: The authors aimed to comprehensively evaluate the efficacy and safety of antibiotic prophylaxis through surgical and nonsurgical scenarios and assess the strength of evidence. Materials and methods: The authors performed an umbrella review of meta-analyses of randomized controlled trials (RCTs). An evidence map was created to summarize the absolute benefits of antibiotic prophylaxis in each scenario and certainty of evidence. Results: Seventy-five meta-analyses proved eligible with 725 RCTs and 78 clinical scenarios in surgical and medical prophylaxis. Of 119 health outcomes, 67 (56.3%) showed statistically significant benefits, 34 of which were supported by convincing or highly suggestive evidence from RCTs. For surgeries, antibiotic prophylaxis may minimize infection occurrences in most surgeries except Mohs surgery, simple hand surgery, herniorrhaphy surgery, hepatectomy, thyroid surgery, rhinoplasty, stented distal hypospadias repair, midurethral sling placement, endoscopic sinus surgery, and transurethral resection of bladder tumors with only low to very low certainty evidence. For nonsurgery invasive procedures, only low to very low certainty evidence showed benefits of antibiotic prophylaxis for cystoscopy, postoperative urinary catheterization, and urodynamic study. For medical prophylaxis, antibiotic prophylaxis showed greater benefits in nonemergency scenarios, in which patients were mainly with weakened immune systems, or at risk of recurrent chronic infections. Antibiotics prophylaxis may increase antibiotic resistance or other adverse events in most scenarios and reached significance in cystoscopy, afebrile neutropenia following chemotherapy and hematopoietic stem cell transplantation. Conclusions: Antibiotic prophylaxis in surgical and nonsurgical scenarios is generally effective and seems independent of surgical cleanliness and urgency of diseases. Its safety is not well determined due to lack of available data. Nevertheless, the low quality of current evidence limits the external validity of these findings, necessitating clinicians to judiciously assess indications, balancing low infection rates with antibiotic-related side effects. [ABSTRACT FROM AUTHOR]