[Comparison of the virtual surgical planning position of maxilla and condyle with the postoperative real position in patients with mandibular protrusion].

OBJECTIVE: To compare the difference between virtual surgical planning (VSP) position and postoperative real position of maxilla and condyle, and to explore the degree of intraoperative realization of VSP after orthognathic surgery. METHODS: In this study, 36 patients with mandibular protrusion deformity from January 2022 to December 2022 were included. All the patients had been done bilateral sagittal split ramus osteotomy (SSRO) combined with Le Fort Ⅰ osteotomy under guidance of VSP. The VSP data (T0) and 1-week postoperative CT (T1) were collected, the 3D model of postoperative CT was established and segmented into upper and lower jaws in CCMF Plan software. At the same time, accor-ding to the morphology of palatal folds, the virtual design was registered with the postoperative model, and the unclear maxillary dentition in the postoperative model was replaced. Then the postoperative model was matched with VSP model by registration of upper skull anatomy that was not affected by the operation. The three-dimensional reference plane and coordinate system were established. Selecting anatomical landmarks and their connections of condyle and maxilla for the measurement, we compared the coordinate changes of marker points in three directions, and the angle changes between the line connecting the marker points and the reference plane to analyze the positional deviation and the angle deviation of the postoperative condyle and maxilla compared to VSP. RESULTS: The postoperative real position of the maxilla deviates from the VSP by nearly 1 mm in the horizontal and vertical directions, and the anteroposterior deviation was about 1.5 mm. In addition, most patients had a certain degree of counterclockwise rotation of the maxilla after surgery. Most of the bilateral condyle moved forward, outward and downward (the average distance deviation was 0.15 mm, 1.54 mm, 2.19 mm, respectively), and rotated forward, outward and upward (the average degree deviation was 4.32°, 1.02°, 0.86°, respectively) compared with the VSP. CONCLUSION: VSP can be mostly achieved by assistance of 3D printed occlusal plates, but there are certain deviations in the postoperative real position of maxilla and condyle compared with VSP, which may be related to the rotation axis of the mandible in the VSP. It is necessary to use patient personalized condylar rotation axis for VSP, and apply condylar positioning device to further improve surgical accuracy.

Modeling denitrification nitrogen losses in China's rice fields based on multiscale field-experiment constraints.

Denitrification plays a critical role in soil nitrogen (N) cycling, affecting N availability in agroecosystems. However, the challenges in direct measurement of denitrification products (NO, N2 O, and N2 ) hinder our understanding of denitrification N losses patterns across the spatial scale. To address this gap, we constructed a data-model fusion method to map the county-scale denitrification N losses from China's rice fields over the past decade. The estimated denitrification N losses as a percentage of N application from 2009 to 2018 were 11.8 ± 4.0% for single rice, 12.4 ± 3.7% for early rice, and 11.6 ± 3.1% for late rice. The model results showed that the spatial heterogeneity of denitrification N losses is primarily driven by edaphic and climatic factors rather than by management practices. In particular, diffusion and production rates emerged as key contributors to the variation of denitrification N losses. These findings humanize a 38.9 ± 4.8 kg N ha-1 N loss by denitrification and challenge the common hypothesis that substrate availability drives the pattern of N losses by denitrification in rice fields.

A global dataset of biochar application effects on crop yield, soil properties, and greenhouse gas emissions.

Biochar application is widely studied to mitigate the threats of soil degradation to food security and climate change. However, there are big variations in the effects of biochar application on crops, soils, and the atmosphere during crop production. This study provides a global dataset of biochar application effects on crop yield, soil properties, and greenhouse emissions. The dataset is extracted and integrated from 367 peer-reviewed studies with 891 independent field, laboratory, and incubation experiments across 37 countries. This dataset includes 21 variables before and after biochar application (including soil properties, crop yield, greenhouse gas emissions, etc.) of 2438 items, focusing on two main biochar application types: biochar application alone and combined with fertilizers. Background information on climate conditions, initial soil properties, management practices, and characteristics of biochar sources and production is also contained in the dataset. This dataset facilitates a comprehensive understanding of the impact of biochar application, supports the utilization of agricultural wastes for biochar production, and assists researchers in refining experimental protocols for further studies.

Aesthetic effect evaluation of the xenogeneic collagen matrix in keratinized mucosa augmentation around dental implants / 口腔疾病防治

Objective@#To evaluate the stability and aesthetic effect of a xenogeneic collagen matrix (mucograft) on achieving an adequate keratinized mucosa width (KMW) around implants and to provide a reference basis for the clinical application of xenogeneic collagen matrix materials.@*Methods@#The hospital ethics committee approved the study protocol, and the patients provided informed consent. Twenty patients with a KMW<2 mm at the buccal implant site who were treated in Binzhou Medical University Affiliated Yantai Stomatological Hospital from July 2020 to September 2022 were included, and a total of 36 implants were included. The mean age of the patients was (52.0±10.4) years, of which 18 were females and 2 were males. They were divided into a free gingival graft group (FGG, control group) and a xenogeneic collagen matrix group (test group) according to different graft materials. The incremental effect of the KMW on the buccal side of the implant and the mucosal shrinkage rate was measured at 1 month and 3 months after the operation. The mucosal scar index (MSI) was evaluated after the operation.@*Results@#At 3 months postoperatively, the KMW was (3.67 ± 1.06) mm in the control group and (2.96 ± 0.98) mm in the test group, and the difference was statistically significant (t = 2.076, P<0.05). The KMW shrinkage rate was (33.34 ± 16.30) % in the test group and (22.05 ± 15.47) % in the control group at 1 month postoperatively and (51.95 ± 12.60) % in the test group and (37.44 ± 16.30) % in the control group at 3 months postoperatively, with statistically significant differences between the two groups at the same time points (P<0.05). Three months after surgery, the test group showed significantly better outcomes than the control group in terms of the five scar indicators (scar width, scar convexity, scar color, scar trace, and overall appearance), and the difference was statistically significant (P<0.05).@*Conclusion@#Xenogeneic collagen matrix can increase the peri-implant KMW and achieve a more natural and coordinated soft tissue aesthetic effect but with a higher shrinkage rate.

Do not ignore the effects of phosphorus and potassium addition on microbial carbon use efficiency.

P or PK addition significantly affected microbial CUE. No significant linear correlation between respiration rates and microbial CUE under N addition when NP and NPK addition were excluded.

Global magnitude of rhizosphere effects on soil microbial communities and carbon cycling in natural terrestrial ecosystems.

The rhizosphere is one of the most dynamic interfaces on the Earth. Understanding the magnitudes of rhizosphere effects (RE, difference in bio-physicochemical properties between rhizosphere and bulk soils) on soil microbial communities and their moderators is important for studying on below-ground carbon (C) cycling. A comprehensive meta-analysis was conducted to quantify the REs on soil microbial biomass, community structure, respiration, and C-degrading enzymes. We found that REs on soil C and nutrients, total microbial biomass, the abundance of specific microbial groups, fungi to bacteria ratio, respiration, and C-degrading enzymes were positive, but the magnitudes were varied with biomes, plant functional types, and mycorrhizal types. REs on microbial biomass, respiration, and C-degrading enzymes increased with the increase of mean annual temperature and mean annual precipitation, but decreased with the increase of soil clay, C, nitrogen (N), and phosphorus (P) contents. The REs on microbial biomass and respiration also increased as the REs on soil C:N:P increased. Compared with bulk soil, per unit rhizosphere soil C supported more microbial biomass, per unit of which respired more C, leading to faster C decomposition in rhizosphere. Our findings indicate that the increase in microbial biomass, co-metabolism induced by labile and energy-rich organic C of root exudates, and overflow respiration induced by stoichiometric imbalance together contribute to the enhanced C decomposition in rhizosphere. The global pattern of REs on soil microbial communities is critical to revealing the plant-microbe-soil interactions in terrestrial ecosystems.

Large differences in ammonia emission factors between greenhouse and open-field systems under different practices across Chinese vegetable cultivation.

Estimating ammonia (NH3) emission factors (EFs) for vegetable production can support assessment of potential atmospheric pollution risk and provide information for mitigating NH3 volatilization. The EFs in greenhouse and open-field systems under different fertilization, irrigation regimes, vegetable types and soil properties in both greenhouse and open-field vegetable production systems in China are poorly understood. An integrated analysis was performed, including 282 field measurements of NH3 volatilization from 54 field studies, to quantify ammonia EFs under different management practices and soil properties. The results showed that the mean ammonia EF across all measurements was 4.2 % (3.6 %-4.8 %). The EFs of greenhouse and open-field systems were 2.0 % (1.5 %-2.5 %) and 6.3 % (5.4 %-7.2 %), respectively. There was a power function relationship between nitrogen application rate and ammonia EF in greenhouses. No relationship was identified between nitrogen application rate and ammonia EF in the open-field system. The EFs of organic fertilizers were lower than those of both chemical fertilizers and the combination of chemical and organic fertilizers. EFs of leafy vegetables, cabbages, solanaceous vegetables and melons were 2.7 %, 2.9 %, 1.4 % and 1.4 % in the greenhouse system, and 5.2 %, 5.7 %, 7.6 % and 9.7 % in the open-field system, respectively. The EFs of the greenhouse production system increased with increasing soil organic matter. Boosted regression tree analysis showed that N application rate, pH and soil organic matter were the main driving factors of EFs in the greenhouse system. Vegetable type, pH and soil organic matter were the main driving factors in the open-field system. In this study, the EFs were evaluated and distinguished across greenhouse and open-field systems, and the results provided accurate EFs under different management practices and soil properties for vegetable production in both greenhouse and open-field systems.

[Impacts of Fertilization on Soil Antibiotic Resistance Genes Across Croplands: A Meta-Analysis].

The objective of this study was to clarify and quantify the impact of fertilizer applications on antibiotic resistance genes (ARGs) in cropland soil. The target was to provide scientific basis for a better understanding of the source and accumulation and transportation characteristics of ARGs in soil and adaptive management strategy-making to secure the ecological environment and human health safety. By collecting data from literature published within the last 20 years (2000-2020), we established a database with 215 and 201 groups of a paired data-set consisting of the quantity and relative abundance of ARGs under independent experimental conditions. Compared to that with no fertilizer, the combined application of organic fertilizer significantly increased the quantity and relative abundance of soil ARGs by 110.0% and 91.0%, respectively. However, chemical fertilization had no significant effect on soil ARGs. The increment of relative abundance of soil ARGs by the combined application of organic fertilizer in the subtropical region was equivalent to 2.6 times that in the warm temperate zone. Compared with that in black soil and dark brown soil, the combined application of organic fertilizer significantly increased the relative abundance of ARGs in red soil and paddy soil in the subtropical region. The increment for the quantity of ARGs (147.6%) by the combined application of organic fertilizer in soil with pH<7 was significantly higher than that in soil with pH>7(110.4%). Compared to poultry manure, livestock manure application significantly increased the quantity and relative abundance of ARGs. The increment of the relative abundance of organic fertilizer to sulfonamide, multidrug, and macrolide ARGs (170.5%-201.2%) was significantly higher than that of quinolone, tetracycline, and aminoglycoside ARGs (61.5%-115.6%). After more than 10 years of applying organic fertilizer, the quantity of soil ARGs significantly increased by 104.2%-112.3%, whereas the effect on the relative abundance was uncertain. Climate, soil spatial properties, and source and amount of organic fertilizer were the main factors affecting the accumulation of ARGs in farmland soil. Management strategies and solutions should pay more attention to effectively minimizing the accumulation and spread of ARGs in agro-ecosystems for high-quality agricultural development in the future.

Coastal reclamation alters soil microbial communities following different land use patterns in the Eastern coastal zone of China.

Coastal reclamation seriously disturbs coastal wetland ecosystems, while its influences on soil microbial communities remain unclear. In this study, we examined the impacts of coastal reclamation on soil microbial communities based on phospholipid fatty acids (PLFA) analysis following the conversion of Phragmites australis wetlands to different land use types. Coastal reclamation enhanced total soil microbial biomass and various species (i.e., gram-positive bacterial, actinomycete, saturated straight-chain, and branched PLFA) following the conversion of P. australis wetland to aquaculture pond, wheat, and oilseed rape fields. In contrast, it greatly decreased total soil microbial biomass and various species following the conversion of P. australis wetland to town construction land. Coastal reclamation reduced fungal:bacterial PLFA, monounsaturated:branched PLFA ratios, whereas increasing gram-positive:gram-negative PLFA ratio following the conversion of P. australis wetland to other land use types. Our study suggested that coastal reclamation shifted soil microbial communities by altering microbial biomass and community composition. These changes were driven primarily by variations in soil nutrient substrates and physiochemical properties. Changes in soil microbial communities following coastal reclamation impacted the decomposition and accumulation of soil carbon and nitrogen, with potential modification of carbon and nitrogen sinks in the ecosystems, with potential feedbacks in response to climate change.

Plant traits in influencing soil moisture in semiarid grasslands of the Loess Plateau, China.

Large-scale vegetation restoration projects pose threats to water resource security in water-limited regions. Thus, the quantification of how vegetation cover affects soil moisture is of key importance to support effective restoration schemes in drylands. However, the current understanding of such effects remains poor. For this study, an in-situ vegetation-removal experiment was conducted at 36 herbaceous grassland sites having different community compositions and topographical conditions in two adjacent loess watersheds of the Loess Plateau, China. The effects of vegetation cover (vegetation effects) on soil moisture were analyzed across soil profiles (0-180 cm) and two growing seasons. Overall, 13 plant traits and 7 topographic and soil properties were employed to evaluate how community compositions modulated vegetation effects on soil moisture. The results showed that vegetation cover increased soil moisture in the surface layer (0-20 cm) by 6.81% during wet periods (semi-monthly rainfall >30 mm) relative to an in-situ unvegetated control, but primarily induced a decline of soil moisture in the deep soil layer (20-180 cm) by 19.44% across two growing seasons. Redundancy analysis (RDA) and structural equation modeling (SEM) suggested that these vegetation effects on soil moisture were significantly correlated with vegetative height, leaf area, shallow root allocation, and slope gradient. Our study revealed that tall, small-leaved, and shallow-rooted plants on flat topographies were beneficial to soil water retention and replenishment. This implied that current restoration strategies may be significantly improved through the development of optimal communities and diverse terracing measures. Our findings are anticipated to provide effective guidance for soil water conservation, as well as ecosystem rehabilitation in dry and degraded regions.

Long-term straw decomposition in agro-ecosystems described by a unified three-exponentiation equation with thermal time.

Understanding drivers of straw decomposition is essential for adopting appropriate management practice to improve soil fertility and promote carbon (C) sequestration in agricultural systems. However, predicting straw decomposition and characteristics is difficult because of the interactions between many factors related to straw properties, soil properties, and climate, especially under future climate change conditions. This study investigated the driving factors of straw decomposition of six types of crop straw including wheat, maize, rice, soybean, rape, and other straw by synthesizing 1642 paired data from 98 published papers at spatial and temporal scales across China. All the data derived from the field experiments using little bags over twelve years. Overall, despite large differences in climatic and soil properties, the remaining straw carbon (C, %) could be accurately represented by a three-exponent equation with thermal time (accumulative temperature). The lignin/nitrogen and lignin/phosphorus ratios of straw can be used to define the size of labile, intermediate, and recalcitrant C pool. The remaining C for an individual type of straw in the mild-temperature zone was higher than that in the warm-temperature and subtropical zone within one calendar year. The remaining straw C after one thermal year was 40.28%, 37.97%, 37.77%, 34.71%, 30.87%, and 27.99% for rice, soybean, rape, wheat, maize, and other straw, respectively. Soil available nitrogen and phosphorus influenced the remaining straw C at different decomposition stages. For one calendar year, the total amount of remaining straw C was estimated to be 29.41 Tg and future temperature increase of 2 °C could reduce the remaining straw C by 1.78 Tg. These findings confirmed the long-term straw decomposition could be mainly driven by temperature and straw quality, and quantitatively predicted by thermal time with the three-exponent equation for a wide array of straw types at spatial and temporal scales in agro-ecosystems of China.

Carbon and Nitrogen Mineralization in Relation to Soil Particle-Size Fractions after 32 Years of Chemical and Manure Application in a Continuous Maize Cropping System.

Long-term manure application is recognized as an efficient management practice to enhance soil organic carbon (SOC) accumulation and nitrogen (N) mineralization capacity. A field study was established in 1979 to understand the impact of long-term manure and/or chemical fertilizer application on soil fertility in a continuous maize cropping system. Soil samples were collected from field plots in 2012 from 9 fertilization treatments (M0CK, M0N, M0NPK, M30CK, M30N, M30NPK, M60CK, M60N, and M60NPK) where M0, M30, and M60 refer to manure applied at rates of 0, 30, and 60 t ha(-1) yr(-1), respectively; CK indicates no fertilizer; N and NPK refer to chemical fertilizer in the forms of either N or N plus phosphorus (P) and potassium (K). Soils were separated into three particle-size fractions (2000-250, 250-53, and <53 µm) by dry- and wet-sieving. A laboratory incubation study of these separated particle-size fractions was used to evaluate the effect of long-term manure, in combination with/without chemical fertilization application, on the accumulation and mineralization of SOC and total N in each fraction. Results showed that long-term manure application significantly increased SOC and total N content and enhanced C and N mineralization in the three particle-size fractions. The content of SOC and total N followed the order 2000-250 µm > 250-53 µm > 53 µm fraction, whereas the amount of C and N mineralization followed the reverse order. In the <53 µm fraction, the M60NPK treatment significantly increased the amount of C and N mineralized (7.0 and 10.1 times, respectively) compared to the M0CK treatment. Long-term manure application, especially when combined with chemical fertilizers, resulted in increased soil microbial biomass C and N, and a decreased microbial metabolic quotient. Consequently, long-term manure fertilization was beneficial to both soil C and N turnover and microbial activity, and had significant effect on the microbial metabolic quotient.

Climate, soil texture, and soil types affect the contributions of fine-fraction-stabilized carbon to total soil organic carbon in different land uses across China.

Mineral-associated organic carbon (MOC), that is stabilized by fine soil particles (i.e., silt plus clay, <53 µm), is important for soil organic carbon (SOC) persistence and sequestration, due to its large contribution to total SOC (TSOC) and long turnover time. Our objectives were to investigate how climate, soil type, soil texture, and agricultural managements affect MOC contributions to TSOC in China. We created a dataset from 103 published papers, including 1106 data points pairing MOC and TSOC across three major land use types: cropland, grassland, and forest. Overall, the MOC/TSOC ratio ranged from 0.27 to 0.80 and varied significantly among soil groups in cropland, grassland, and forest. Croplands and forest exhibited significantly higher median MOC/TSOC ratios than in grassland. Moreover, forest and grassland soils in temperate regions had higher MOC/TSOC ratios than in subtropical regions. Furthermore, the MOC/TSOC ratio was much higher in ultisol, compared with the other soil types. Both the MOC content and MOC/TSOC ratio were positively correlated with the amount of fine fraction (silt plus clay) in soil, highlighting the importance of soil texture in stabilizing organic carbon across various climate zones. In cropland, different fertilization practices and land uses (e.g., upland, paddy, and upland-paddy rotation) significantly altered MOC/TSOC ratios, but not in cropping systems (e.g., mono- and double-cropping) characterized by climatic differences. This study demonstrates that the MOC/TSOC ratio is mainly driven by soil texture, soil types, and related climate and land uses, and thus the variations in MOC/TSOC ratios should be taken into account when quantitatively estimating soil C sequestration potential of silt plus clay particles on a large scale.