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Introduction: This purpose of this work is to give a detailed description of a surgical technique for frameless robot-assisted asleep deep brain stimulation (DBS) of the centromedian thalamic nucleus (CMT) in drug-resistant epilepsy (DRE). Methods: Ten consecutively enrolled patients who underwent CMT-DBS were included in the study. The FreeSurfer "Thalamic Kernel Segmentation" module and experience target coordinates were used for locating the CMT, and quantitative susceptibility mapping (QSM) images were used to check the target. The patient's head was secured with a head clip, and electrode implantation was performed with the assistance of the neurosurgical robot Sinovation®. After opening the dura, the burr hole was continuously flushed with physiological saline to stop air from entering the skull. All procedures were performed under general anesthesia without intraoperative microelectrode recording (MER). Results: The mean age of the patients at surgery and onset of seizures was 22 years (range 11–41 years) and 11 years (range 1–21 years), respectively. The median duration of seizures before CMT-DBS surgery was 10 years (2–26 years). CMT was successfully segmented, and its position was verified by experience target coordinates and QSM images in all ten patients. The mean surgical time for bilateral CMT-DBS in this cohort was 165 ± 18 min. The mean pneumocephalus volume was 2 cm3. The median absolute errors in the x-, y-, and z-axes were 0.7 mm, 0.5 mm, and 0.9 mm, respectively. The median Euclidean distance (ED) and radial error (RE) was 1.3 ± 0.5 mm and 1.0 ± 0.3 mm, respectively. No significant difference was found between right- and left-sided electrodes regarding the RE nor the ED. After a mean 12-month follow-up, the average reduction in seizures was 61%, and six patients experienced a ≥ 50% reduction in seizures, including one patient who had no seizures after the operation. All patients tolerated the anesthesia operation, and no permanent or serious complications were reported. Conclusions: Frameless robot-assisted asleep surgery is a precise and safe approach for placing CMT electrodes in patients with DRE, shortening the surgery time. The segmentation of the thalamic nuclei enables the precise location of the CMT, and the flow of physiological saline to seal the burr holes is a good way to reduce the influx of air. CMT-DBS is an effective method to reduce seizures. [ABSTRACT FROM AUTHOR]

To explore the effects of biochar application on CO2 and CH4 emissions as well as the temperature response of CO2 emissions, a 1-year experiment was conducted with three treatments (control; CF, chemical fertilizer only; BCF, biochar combined with chemical fertilizer) in a vegetable field. The results showed that (1) compared with CF, short-term application of biochar significantly enhanced the cumulative CO2 emissions by 27.5% from a soil–plant system by increasing the soil microbial biomass (e.g., MBC) and C substrates (e.g., SOC); (2) lowest emissions of CH4 were observed in the BCF treatment, and an increase in CH4 consumption and reduced competition with NH4+ may be responsible for the significant reduction in CH4 source strength in biochar-amended soil; and (3) activation energy (Ea) was identified as an important factor influencing the temperature sensitivity (Q10) of CO2 emissions. Fertilization (CF and BCF) reduced the average Q10 and Ea values of CO2 emissions by 9.0–26.7% and 23.5–10.1%, respectively, relative to the control. In addition, the average Ea value in the BCF treatment (51.9 kJ mol−1) was significantly higher than those in the control and CF treatments. The increase in Q10 and Ea values following biochar application possibly contributed to the supplementation of limited labile C and nutrients but highly resistant C following biochar application. Soil pH and crop cultivation may play key roles in influencing the change in Ea. Our study concludes that biochar amendment increased CO2 emissions and temperature response of CO2 emission from the soil–plant system while reducing CH4 emissions. [ABSTRACT FROM AUTHOR]

Controlled release fertilizer (CRF) has been shown to increase crop yield and N use efficiency (NUE) compared with traditional chemical fertilizer (TF). However, few studies examined the effects of CRF on CH4, N2O, and NO emissions simultaneously in alkaline paddy fields under rice–wheat rotation. In the present study, we conducted a 2-year field experiment to compare the effects of different CRF application strategies on these gas emissions with those of TF and explored the effects of CRF on global warming potential (GWP), crop yields, and greenhouse gas emission intensity (GHGI). Results showed that CRF can reduce 0.98–14.3%, 13.3–21.1%, and 8.22–16.3% of CH4, N2O, and NO emissions, respectively, in the studied alkaline paddy field. CRF reduce CH4 emission probably by regulating soil NH4+ concentration. CRF reduce N2O and NO emissions probably by regulating inorganic N content in the studied alkaline paddy soil. CRF had the same effect on annual crop yield as TF, especially when CRF was applied twice in each season and had the same N application rate as TF. Annual crop yields and the agronomic efficiency of N (AEN) increased by 8.24% and 21.6%, respectively. On the average of the two rice–wheat rotation cycles, GHGI significantly decreased by up to 14.1% after the application of CRF as relative to that after the application of TF (P < 0.05). These results suggest that CRF is an environment-friendly N fertilization strategy for mitigating GWP and ensuring high crop yield in an alkaline paddy field under rice–wheat rotation. [ABSTRACT FROM AUTHOR]

Purpose: Phosphorus (P) is the main factor limiting crop production in red soils. Examining the bacterial community harboring phoD gene under different long-term cropping systems may supply meaningful insights for improving soil P availability. Here, we analyzed how the cropping systems affect community structure of phoD-harboring bacteria by changing physicochemical properties in red soils. Materials and methods: Twenty-four soil samples from eight cropping systems (abandoned farmland, corn continuous cropping, mango continuous cropping, taro continuous cropping, zucchini–corn rotation, pea–corn rotation, canola–tobacco rotation, and walnut–tobacco intercropping for > 10 years) were collected from 0 to 20 cm depth in Miyi County, Sichuan Province, China. The abundance of phoD gene was determined by quantitative PCR, and phoD-harboring bacterial community structure was analyzed by high-throughput sequencing. Results and discussion: Available P concentration and phoD abundance were the highest in pea-corn rotation soil, while alkaline phosphatase (ALP) activity was the lowest in this soil. Available P showed a significant positive relationship with phoD abundance, while a negative relationship with ALP activity. Moreover, the dominant phyla of phoD-harboring bacterial community were Proteobacteria and Actinobacteria, with Cupriavidus and Bradyrhizobium being the dominant genera. The relative abundances of Streptomyces, Pseudomonas, and Amycolatopsis were positively related to soil P concentration (total and available P) and negatively related to ALP activity, indicating that these genera may be essential in the mineralization of soil organic P. Redundancy analysis (RDA) showed that ALP, soil organic carbon (SOC), and N:P ratio were the remarkable factors affecting the structure of phoD-containing bacterial community across all cropping system soils. Meanwhile, structural equation model (SEM) showed that the effects of total N and available P on soil phoD-harboring bacterial community structure were stronger than that of SOC. Further, soil texture was also one of the main factors affecting the phoD-harboring bacterial community structure, which had a notable up-regulation effect on abundance and diversity of phoD gene and indirectly regulate gene composition by affecting available P. Conclusions: The long-term cropping systems can affect the community structure of phoD-containing bacteria and ALP activity by altering physicochemical properties, and thus contribute to regulation of the biogeochemical cycle of P in red soils. The main factors driving the changes in phoD-harboring bacterial community structure were soil texture, SOC, total N, and available P. [ABSTRACT FROM AUTHOR]

Key message: We genome-wide identified 28 JmjC domain-containing genes, further spatio-temporal expression profiling and genetic analysis defined them as epigenetic regulators in flowering initiation of Rosa chinensis. The JmjC domain-containing histone demethylases play critical roles in maintaining homeostasis of histone methylations, thus are vital for plant growth and development. Genome-wide identification of the JmjC domain-containing genes have been reported in several species, however, no systematic study has been performed in rose plants. In this paper, we identified 28 JmjC domain-containing genes from the newly published genome database of Rosa chinensis. The JmjC domain-containing proteins in R. chinensis were divided into seven groups, KDM3 was the largest group with 13 members, and JmjC domain-only A and KDM5B were the smallest clades both with only one member. Although all the JmjC domain proteins having a conserved JmjC domain, the gene and protein structure experienced differentiation and specification during the evolution, especially in KDM3 clade, one gene (RcJMJ40) was found carrying site deletions for cofactors Fe (II) and α-KG binding which were crucial for demethylase activities, three genes (RcJMJ41, RcJMJ43 and RcJMJ44) had no intron while two of them had tandem JmjC domains. Spatial expression pattern analysis of these JmjC domain-containing genes in different tissues showed most of them were highly expressed in reproductive tissues such as floral meristem and closed flowers than vegetative tissues, demonstrating their important functions in developmental switch from vegetative to reproductive growth of roses. Temporal expression profiling indicated majority of JmjC domain-containing genes from R. chinensis fluctuated along with floral bud differentiation and development, further proving their essential roles in flower organogenesis. VIGS induced silencing of RcJMJ12 led to delayed flowering time, and decreased the expression levels of flowering integrator such as RcFT, RcSOC1, RcFUL, RcLFY and RcAP1, therefore providing the genetic evidence of RcJMJ12 in flowering initiation. Collectively, spatio-temporal expression profiling and genetic analysis defined the JmjC domain-containing genes as important epigenetic regulators in flower development of R. chinensis. [ABSTRACT FROM AUTHOR]

Purpose: Phosphorus (P) fertilizer has been applied in regions with red soils to ensure high crop yield. However, the supply of bioavailable P for crop plants is insufficient due to the strong adsorption and fixing behaviors in red soils. In this study, we explored P adsorption and desorption characteristics in red soils under different long-term cropping systems. We also analyzed how the cropping systems affect P adsorption and desorption through changing soil physicochemical properties under the experimental conditions. Materials and methods: Eighteen red soil samples were collected at depths of 0–20 cm from six cropping systems (abandoned farmland, corn continuous cropping, taro continuous cropping, pea–corn rotation, canola–tobacco rotation, and walnut–tobacco intercropping for at least 10 years) in Miyi County, Sichuan Province, China. Soil physicochemical properties, zeta potentials, and P adsorption and desorption characteristics were evaluated. Results and discussion: The P adsorption capacity of soils increased at a decreasing rate with increasing exogenous P concentration, while the P desorption capacity increased constantly; however, the change in the percentage of desorbed P had no clear trend. The soils under pea–corn rotation and taro continuous cropping had lower P adsorption capacities and higher P desorption capacities compared to those under the other cropping systems. The maximum P adsorption capacities (Qm) of pea–corn rotation and taro continuous cropping soils were 16.1% and 32.4% of abandoned farmland soil, while the corresponding desorption coefficients were 6.93 and 1.62 times higher than that of abandoned farmland soil, respectively. Soil available P (AP), cation exchange capacity (CEC), and clay content were positively correlated with a and readily desorbable P (RDP), while they were negatively correlated with Qm (P < 0.05); opposite trends were found in the sand content. In addition, the zeta potential of soil colloids decreased with increasing soil pH. Among the cropping systems, the absolute value of zeta potential was lowest for tobacco–walnut intercropping, while its isoelectric point was the highest, resulting in the highest P adsorption capacity. Conclusions: The long-term cropping systems affect P adsorption and desorption characteristics and P availability in red soils by influencing soil physicochemical properties. The main factors driving the changes in P adsorption behavior were AP, CEC, free Fe oxides, and sand content, while AP, sand, and clay contents were the major factors for the P desorption. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to test the hypothesis that readily degradable Carbon (C) has contrasting effect on soil N autotrophic and heterotrophic nitrification, can stimulate nitrous oxide (N2O) emission. The knowledge can improve our understanding of the effect of readily degradable C on soil N nitrification and the related N2O emission. Materials and methods: 15N tracing technique along with acetylene inhibition was used to determine the effect of different doses of glucose-C addition on the rates of total nitrification (ntot), autotrophic nitrification (na), heterotrophic nitrification (nh), and N2O production in two soils. Soils were collected from Glenormiston (GN) and Terang (TR), Victoria, Australia and incubated at soil moisture content of 60% water-filled pore space (WFPS) and at 25 °C. Results and discussion: The addition of mixed C and N substrates with wide C/N ratio (> 25) promoted heterotrophic nitrification by 2.84- to 3.33-folds but inhibited autotrophic nitrification by 30.4–54.8%, thereby resulting in high ntot and NO3− accumulation compared with the soil samples under the control treatment. The mechanism of glucose inhibition of na might be caused by increasing the microbial immobilization of NH4+ and not by affecting the gene copy numbers of ammonia-oxidizing archea and ammonia-oxidizing bacteria. The glucose addition stimulated N2O production in soil, which might be caused by promoting heterotrophic nitrification and denitrification. Conclusions: The stimulating effect of degradable C application on the contribution of heterotrophic nitrification to total nitrification, NO3− accumulation, and N2O production should be considered, especially in soils with low pH and high organic C content. [ABSTRACT FROM AUTHOR]

Most cases of Usher syndrome type II (USH2) are due to mutations in the USH2A gene. There are no effective treatments or ideal animal models for this disease, and the pathological mechanisms of USH2 caused by USH2A mutations are still unknown. Here, we constructed a ush2a knockout (ush2a−/−) zebrafish model using TALEN technology to investigate the molecular pathology of USH2. An early onset auditory disorder and abnormal morphology of inner ear stereocilia were identified in the ush2a−/− zebrafish. Consequently, the disruption of Ush2a in zebrafish led to a hearing impairment, like that in mammals. Electroretinography (ERG) test indicated that deletion of Ush2a affected visual function at an early stage, and histological analysis revealed that the photoreceptors progressively degenerated. Rod degeneration occurred prior to cone degeneration in ush2a−/− zebrafish, which is consistent with the classical description of the progression of retinitis pigmentosa (RP). Destruction of the outer segments (OSs) of rods led to the down-regulation of phototransduction cascade proteins at late stage. The expression of Ush1b and Ush1c was up-regulated when Ush2a was null. We also found that disruption of fibronectin assembly at the retinal basement membrane weakened cell adhesion in ush2a−/− mutants. In summary, for the first time, we generated a ush2a knockout zebrafish line with auditory disorder and retinal degeneration which mimicked the symptoms of patients, and revealed that disruption of fibronectin assembly may be one of the factors underlying RP. This model may help us to better understand the pathogenic mechanism and find treatment for USH2 in the future. [ABSTRACT FROM AUTHOR]

Strategies to reduce cadmium (Cd) in rice grain, below concentrations that represent serious human health concerns, require that the mechanisms of Cd distribution and accumulation within rice plants be established. Here, a comprehensive hydroponic experiment was performed to investigate the differences in the Cd uptake, chelation and compartmentalization between high (D83B) and low (D62B) Cd-accumulation cultivars contrasting in Cd accumulation in order to establish the roles of these processes in limiting Cd translocation from root to shoot. D83B showed 3-fold higher Cd accumulation in the shoots than the cultivar D62B. However, a short-term Cd uptake experiment showed more Cd uptake by D62B than by D83B. The distribution of Cd in roots and shoots differed significantly. D83B translocated 38% of total Cd taken up to the shoots, whereas D62B retained most of the Cd in the roots. D62B had higher amounts of non-protein thiols (NPTs) and glutathione (GSH) than D83B. The NPT and Cd distribution ratio (CDR) in the anionic form in the roots of D62B increased gradually as Cd concentration increased. In D83B, in contrast, levels of CDR in the cationic form increased significantly from 22.10 to 43.37%, while NPT only increased slightly. Furthermore, the percentage of Cd ions retained in thiol-rich peptides, especially in the HMW complexes, was significantly higher in D62B compared with D83B. However, D83B possessed a greater proportion of potentially mobile (cationic) Cd in the roots and showed superior Cd translocation from root to shoot. Taken as a whole, the results presented in this study revealed that Cd chelation, compartmentalization and adsorption contribute to the Cd retention in roots. [ABSTRACT FROM AUTHOR]

Semi-agricultural ecosystems in peri-urban areas are susceptible to contamination. The spatial distribution and influencing factors of such pollution are unclear and poorly constrained in many areas worldwide. Therefore, studying the problems of soil pollution in peri-urban areas is critical for environmental management and agricultural production. In this paper, with cadmium (Cd) as the target pollutant, the spatiotemporal variations of soil cadmium pollution and the relative importance of the affecting factors were analyzed at a peri-urban area from the Jingyang District, Sichuan, China. Statistical results showed that the farmland in the study area could be considered moderately soil Cd-polluted, under the dual influence of natural factors and human activity. In particular, the soil Cd concentration in Tianyuan and Bajiaojing exceeded 0.5 mg kg, for intensive industrial enterprises are distributed in these areas. Correspondingly, the geoaccumulation index also showed that the contamination of Cd in this area was moderately polluted. Moreover, the ecological risk index was 80% in the study area, indicating that the soil Cd pollution potential risk was moderate to high. High geological background values (soil Cd = 0.29 mg kg), river migration, industrial enterprises, and traffic significantly influenced soil Cd pollution, with natural geological factors playing greater roles. The significant horizontal-spatial effective distances away from Shiting River, Deyang-Aba Highway, and chemical plants were 200, 400, and 100 m, respectively. These results will be useful in guiding farmland cultivation and pollution remediation effectively in the peri-urban areas. [ABSTRACT FROM AUTHOR]