Clinical efficacy of robotic spine surgery: an updated systematic review of 20 randomized controlled trials.

Purpose: To determine whether using robots in spine surgery results in more clinical advantages and fewer adverse consequences. Methods: Between October 1990 and October 2022, a computer-based search was conducted through the databases of PubMed, Cochrane Library, Embase, Web of Science, China National Knowledge Infrastructure, China Biology Medicine, VIP databases, and WAN FANG. The study only included randomized controlled trials (RCTs) comparing the clinical efficacy and safety of robot-assisted surgery with those of conventional spine surgery. The review was conducted following PRISMA 2020, and AMSTAR-2 was used to evaluate the methodological quality. R version 4.2.1 was used in the meta-analysis. The Cochrane Collaboration Tool was used for evaluating the risk of bias. Results: This study analyzed 954 participants from 20 RCTs involving cervical spondylosis, lumbar degenerative disease, scoliosis, etc. The robot-assisted group outperformed the freehand group in terms of intraoperative blood loss, number of screws in grade A position, grade A + B position, radiation dose, and hospital stay. Operation duration, visual analog scale scores of low back pain, Oswestry disability index, and radiation exposure time did not significantly differ between the two groups. Conclusions: Although robotic spine surgery is more accurate in pedicle screw placement than conventional methods, the robot group did not demonstrate an advantage in terms of clinical efficacy. Studies of complications and cost-effectiveness are still very rare.

[Abundances and Morphology Patterns of Microplastics Under Different Land Use Types on the Loess Plateau].

As an emerging pollutant to the environment, microplastics have received widespread attention worldwide. The Loess Plateau, as one of the major agricultural production areas in China, has various land use types, but how the abundance and morphological patterns of microplastics differ among soils under different land use types remains unclear. In this study, we collected soils from three different land use types:croplands, apple orchards, and landfills in the Wangdonggou Catchment. Microplastics were separated and extracted using a modified density centrifugation method, and the abundance, composition, and morphological characteristics of the soil were analyzed and characterized using a laser infrared imaging system. The results showed that the average abundance of microplastics in the Wangdonggou Catchment was 4715 n·kg-1, mainly composed of PET, PU, and alkyd varnish(ALK), respectively accounting for 30.39%, 29.58%, and 8.42%. More than 80% of the microplastics were fragmented, and more than 60% of the microplastics were of a size ≤ 50 µm. The average abundance of microplastics varied significantly among land use types:cropland soil (7550 n·kg-1)>apple orchard soil (3440 n·kg-1)>landfill soil (2283 n·kg-1). The average area, width, height, eccentricity, circularity, and other morphological characteristics of microplastics in apple orchard soil were significantly different from those in the cropland and landfill soil.

Retrospective Analysis of 28 Cases Confirmed for Primary Angiitis of the Central Nervous System by Biopsy.

OBJECTIVE: The present study aimed to summarize the clinical characteristics, therapeutic effects, and long-term prognosis of cases confirmed with primary angiitis of the central nervous system (PACNS) by biopsy, analyze the risk factors, and provide clinical guidance for the diagnosis and treatment of the disease. METHODS: Retrospective analysis was performed on 28 cases of PACNS confirmed by biopsy, and the age, gender, pathological results, course of the disease, imaging manifestations, treatment, and prognosis of the patients were analyzed and summarized. RESULTS: The cohort (age 16-60 years) comprised of 16 males. The average time from the visit to diagnosis was 6 months. The first symptom was chronic headache in 18 patients. The pathological results were accompanied by demyelination in 10 cases and glial hyperplasia in 6 cases. A total of 27 patients received treatments including glucocorticoid+cyclophosphamide; of these, 3 cases of craniotomy were improved. Among the 28 patients, 15 patients improved after the treatment, 12 patients had no significant improvement, and 1 patient was deceased. Patients with a long course of the disease before diagnosis, a Karnofsky performance status (KPS) score <60 at the time of diagnosis, a behavioral, cognitive abnormality before treatment, and a short-term relapse (0.3-1 month) have a poor outcome. CONCLUSIONS: PACNS patients are prone to misdiagnosis and mistreatment, with unknown etiology and poor prognosis due to delayed treatment. Therefore, early biopsy, pathological diagnosis, and timely treatment with glucocorticoid shock are recommended, and patients with obvious mass effect should be treated by surgical resection.

[Root respiration and its temperature sensitivity at various growth stages of winter wheat in the Loess Plateau, Northwest China]. / é»„åœŸé«˜åŽŸæ—±åœ°å†¬å°éº¦ä¸åŒç”Ÿè‚²æœŸæ ¹ç³»å‘¼å¸åŠå ¶æ¸©åº¦æ•æ„Ÿæ€§.

Understanding the effects of crop growth stage on root respiration (RA) and its temperature sensitivity (Q10) has important theoretical and practical significance for enriching the carbon cycle theory of cropland. In a rain-fed agricultural ecosystem on the Loess Plateau, soil respiration rates were in situ measured in adjacent bare soil (soil microbial respiration, RH) and non-fertilized winter wheat (soil respiration, RS=RA+RH) with an automated CO2 flux system from 2009 to 2014 to investigate the effect of growth stage on RA and Q10. The results showed that net photosynthetic rate in the seedling, elongating, filling, and the ripening stage was 5.9, 14.4, 12.0, and 4.4 µmol·m-2·s-1, and the corresponding root activity was 51.0, 100.8, 84.4, and 31.8 µg·g-1·h-1, respectively. RA differed significantly among different growth stages, which was 0.26, 0.67, 0.91, and 0.56 µmol·m-2·s-1. The variation of RA was closely related with soil moisture, soil temperature, net photosynthetic rate, and root activity, which presented parabolic, exponential, linear, and linear models respectively. Furthermore, Q10 in each stage was 2.61, 4.88, 2.26, and 6.93, respectively, the variation of which was closely related with net photosynthetic rate, root activity, and soil moisture, with the contribution rate of root respiration being 29%, 53%, 46% and 31%, respectively. In conclusion, in addition to environmental factors, growth period of winter wheat was an important factor affecting RA and Q10.

[Effect of Environmental Factors on Variation Characteristics of Soil Microbial Respiration and Its Temperature Sensitivity].

Studying the effect of environmental factors on the variation of soil microbial respiration and its temperature sensitivity (Q10) at different time scales under field conditions is of great significance for accurately understanding the region's climate warming potential. From March 2008 to November 2013, in situ soil microbial respiration rates were determined using an automated CO2 flux system (Li~8100) in long-term bare fallow soil at the Changwu State Key Agro-Ecosystem Experimental Station, Shaanxi, China, for studying the effect of environmental factors on the variation of soil microbial respiration and Q10 at different time scales. At diurnal time scales, the daily variation of soil microbial respiration rates showed a single-peak curve, which was closely related to soil temperature (P<0.05); whereas the daily mean soil microbial respiration rate and Q10 varied with soil moisture, with both showing the order of moderate soil moisture conditions > higher soil moisture conditions > lower soil moisture conditions[daily mean soil microbial respiration rate:1.20 µmol·(m2·s)-1 vs. 0.95 µmol·(m2·s)-1 vs. 0.79 µmol·(m2·s)-1; Q10:2.12 vs. 1.93 vs. 1.59]. At seasonal time scales, both the seasonal mean soil microbial respiration rate and Q10 showed the order of rainy season > non-rainy season[seasonal mean soil microbial respiration rate:1.11 µmol·(m2·s)-1vs. 0.90 µmol·(m2·s)-1; Q10:1.96 vs. 1.59], which was consistent with the trend of soil temperature and moisture (soil temperature:20.39 vs. 14.50℃; soil moisture:49.2% vs. 38.6%). The bivariate model of soil temperature and soil moisture could explain the greater seasonal variability of the soil microbial respiration rate than did the univariate model of soil temperature or soil moisture (R2:0.45-0.82 vs. 0.32-0.67 vs. 0.35-0.86; the fitting coefficient between the simulated and measured soil microbial respiration rates:0.76 vs. 0.64 vs. 0.58). At annual time scales, the annual cumulative soil microbial respiration ranged from 226 to 298 g·(m2·a)-1, with an average of 253 g·(m2·a)-1, and the annual Q10 ranged from 1.48 to 1.94, with an average of 1.70. The annual cumulative soil microbial respiration and Q10 showed a negative quadratic correlation with annual mean soil moisture (P<0.05), with the annual mean soil moisture explaining 39% and 54% of the annual variability of annual cumulative soil microbial respiration and Q10, respectively. In the bare soil treatment, the soil organic carbon decreased from 6.5 g·kg-1 at the beginning of the experiment to 5.5 g·kg-1 at present; whereas, the annual cumulative soil microbial respiration was up to 255 g·(m2·a)-1 and the loss of annual cumulative soil microbial respiration was 20 times larger than the loss of soil organic carbon in the Loess Plateau region, China.

[Contribution of Root Biomass to Soil Organic Carbon Under Complex Landforms Conditions].

Quantifying the contribution of fine root density (FRD) to soil organic carbon density (SOCD) under extremely complex landforms is of great significance for the evaluation of carbon storage at an eroded small catchment in hilly regions of the Loess Plateau. Soil and root samples were collected from typical landforms (a ridge slope, gully slope, and valley bottom) and different vegetation types (cropland, grassland, and woodland) to investigate the contribution of FRD to SOCD at the Zhuan Yaogou watershed The spatial distribution of SOCD and FRD was influenced significantly by landforms, vegetation type, soil depth, or their interactions. SOCD and FRD tended to go in the following order:valley bottom > gully slope > ridge slope on different landforms,Woodland > grassland > cropland on different types of vegetation, and surface > lower depths at different soil depths. Additionally, FRD had a significant effect on SOCD (P<0.05), SOCD increased logarithmically with FRD, and there was a significant difference in root-carbon conversion efficiency between different landforms and types of vegetation (P<0.05). The root-carbon conversion efficiency on the valley bottom (0.87) was 2.0 times higher than those on ridge slopes (0.43) and gully slopes (0.43) on cropland; the root-carbon conversion efficiency on gully slopes (0.57) were 1.3 and 2.1 times greater than those in valley bottoms (0.45) and ridge slopes (0.27), respectively, on grassland; and the root-carbon conversion efficiency on ridge slopes (0.56) was 1.3 times greater than that on gully slopes (0.44). Therefore, from the perspective of increasing root-carbon conversion efficiency at the Zhuan Yaogou watershed in the hilly region of the Loess Plateau, valley bottoms are suitable for agriculture, gully slopes are suitable for returning farmland to grassland, and ridge slopes are suitable for returning farmland to woodland.

A lanthanide-based magnetic nanosensor as an erasable and visible platform for multi-color point-of-care detection of multiple targets and the potential application by smartphone.

The sensitive, selective and point-of-care detection of dipicolinic acid (DPA) is of great significance for the prevention of the anthrax virus and the containment of bioterrorism. In this work, a multi-color fluorescent nanoprobe composed of lanthanides and magnetic nanoparticles (Fe3O4@CePO4:Tb-EDTA-Eu) has been designed, in which the portion of Fe3O4@CePO4:Tb can be used as the internal stable signal of green fluorescence, while the EDTA-Eu part can be used as the sensitive reaction signal for monitoring DPA. Upon the addition of DPA, the red fluorescence of Eu3+ ions is significantly enhanced, while the fluorescent color of the nanoprobes can change from green to red (such as yellow-green, orange-yellow and orange-red), achieving visual multi-color fluorescent detection even by the naked eye. By using the magnetic separation method, the composites can be easily purified for point-of-care testing. More importantly, the nanoprobe fixed test pieces enable real-time analysis of DPA by using an easy-to-access color-scanning application on a smartphone. Furthermore, the fluorescence intensity can be quenched by the addition of Cu2+, which leads to a rewritable nanosensor and can be used in the detection of cysteine (Cys) with high sensitivity. With the addition of Cys, this erasable nano detection platform can also display the original multi-color visual point-of-care detection. With further optimization, this new type of multi-color fluorescent assay is promising in point-of-care clinics for multi-target diagnostics.

Alterations of White Matter Connectivity in Preschool Children with Autism Spectrum Disorder.

Purpose To investigate the topologic architecture of white matter connectivity networks in preschool-aged children with a diagnosis of autism spectrum disorder (ASD) versus typical development (TD). Materials and Methods Forty-two participants were enrolled, including 21 preschool children with ASD (14 male children and seven female children; mean age, 4.56 years ± 0.97 [standard deviation]) and 21 children with TD (11 males and 10 females; mean age, 5.13 years ± 0.82). The diagnosis of ASD was determined according to the Diagnostic and Statistical Manual of Mental Disorders Global Assessment of Functioning scores (mean score, 8.00 ± 0.50). All participants underwent diffusion-tensor imaging (DTI) and T2-weighted imaging on a 3-T magnetic resonance system. A graph theoretical analysis was applied to investigate the topologic organization of the brain network including global and local topologic parameters. Statistical analysis was then performed for the comparison between the groups. Results Compared with the TD group, children with ASD demonstrated shortened characteristic path length (t1 = 0.536, t2 = 0.534, t3 = 0.523, t4 = 0.510, and t5 = 0.501; P < .05) and increased global efficiency (t1 = 0.499, t2 = 0.497, t3 = 0.486, t4 = 0.473, and t5 = 0.465; P < .05) and clustering coefficient (t1 = 0.673, t2 = 0.750, t3 = 0.757, t4 = 0.738, and t5 = 0.741; P < .05). Significant increases in nodal efficiency were mainly found in left pallidum (0.037 vs 0.032, respectively; P < .01) and right caudate nucleus (0.037 vs 0.032, respectively; P < .01) of the basal ganglia network. Conclusion Significantly altered patterns of global and local brain network topography may underlie the abnormal brain development in preschool children with ASD compared with those who have TD. The identification of altered structural connectivity in basal ganglia and paralimbic-limbic networks may point toward potential imaging biomarkers for preschool-age patients with ASD. © RSNA, 2018.

Two de novo variations identified by massively parallel sequencing in 13 Chinese families with children diagnosed with autism spectrum disorder.

Autism spectrum disorder (ASD) is a genetically heterogeneous neurodevelopmental disorder characterized by impairments in social interaction and communication, and by restricted and repetitive behaviors. The genetic architecture of ASD has been elucidated, including chromosomal rearrangements, de novo or inherited rare variants, and copy number variants. However, the genetic mechanism of Chinese families with ASD children is explored rarely. To identify genetic pathogenesis, we performed massively parallel sequencing on 13 Chinese ASD trio families, and found two de novo variations. The novel de novo splice alteration c.664 + 2T > G in the DEAF1 gene and the novel de novo missense mutation c.95 C > T in the AADAT gene associated with ASD may be important clues for exploring the etiology of this disorder.

[Response of Soil Respiration to Extreme Precipitation in Semi-arid Regions].

Evaluating the response of soil microbial respiration to extreme precipitation event is significant for a better understanding about the influence of the change of precipitation regime on soil carbon cycling under global warming. A simulated experiment of extreme precipitations was conducted during the rainy season (July-September 2015) in the Changwu State Key Agro-Ecological Station, Shaanxi, China. The treatments consisted of three total precipitations in rainy season (600 mm, 300 mm, and 150 mm) and two precipitation regimes (10 mm, 150 mm; P10, P150). Soil microbial respiration varied differently in the same single rainfall event among three precipitations. The variation coefficient of soil microbial respiration under 600 mm total precipitation was 36% (P150) and 33% (P10), and 28% and 22% under 300 mm total precipitation, 43% and 29% under 150 mm total precipitation. Under 600 mm total precipitation, the cumulative soil microbial respiration under P150 was 20% less than that under P10; however, the cumulative soil respiration of P150 under 150 mm total precipitation was 22% more than that under P10; and there was no significant difference between P10 and P150 under 300 mm total precipitation. Therefore, the duration in soil water stress must be considered to estimate soil microbial respirations under extreme precipitations.

[Variation of Soil CO2 Flux and Environmental Factors Across Erosion-Deposition Sites Under Simulation Experiment].

The CO2 flux from soil is an important component of global carbon cycle, and a small variation of soil CO2 flux can prominently influence atmospheric CO2 concentration and soil organic carbon stock. Soil erosion significantly influences soil CO2 emission. However, the process of soil CO2 flux during soil erosion and soil deposition remains uncertain. At the present study, a simulated experiment on soil erosion and deposition was conducted at Changwu State Key Agro-Ecological Station, Shaanxi, China. From July to September in 2014 and 2015, soil CO2 flux was periodically measured using an automated CO2 flux system LI-8100 (LI-COR, Lincoln, NE, USA) and soil temperature and moisture were collected by series data collection system of soil temperature and soil moisture (EM50, DECAGON, USA). The measurement frequency of soil CO2 flux was once a week during 09:00 and 11:00. Soil temperature and soil moisture of 10 cm topsoil were measured continuously (at an interval of 30 minutes) during the experiment. At the same time, runoff and sediment were collected as well in each rain event, and then SOC content in sediment was measured. The results showed that soil CO2 flux between erosion and deposition sites had a significant difference (P<0.05), and soil CO2 flux at deposition site [mean value 1.38 µmol·(m2·s)-1] was 31% higher than that of soil CO2 flux at deposition site [1.05 µmol·(m2·s)-1], while temperature sensitivity at deposition site (Q10:8.14) was 3 times as high as that at erosion site (2.34). Soil moisture at deposition site was 19% higher than that at erosion site (P<0.05). Soil temperature was slightly higher at erosion site. The average SOC content (7.26 g·kg-1) increased by 6% in the sediment compared with the initial SOC content (6.83 g·kg-1). Soil moisture and SOC redistribution across erosion and deposition sites were influencing factors for soil CO2 flux under erosional environment. In conclusion, soil CO2 flux showed a significant variation at erosion site and deposition site. Changes in soil moisture and SOC contributed much to the difference in soil CO2 flux across erosion and deposition sites.

[Differences in soil organic carbon and total nitrogen and their impact factors under different restoration patterns in the Loess Plateau.] / é»„åœŸåŒºä¸åŒé€€è€•æ–¹å¼ä¸‹åœŸå£¤ç¢³æ°®çš„å·®å¼‚åŠå ¶å½±å“å› ç´ .

Knowledge of the effect of different vegetation restoration measures on soil organic carbon (SOC) and total soil nitrogen (TN) is of importance to better understand carbon and nitrogen cycling in terrestrial ecosystems and deal with the global greenhouse effect. The differences in SOC and TN content in 0-100 cm soil profile between different restoration measures and their impact factors were investigated in the Loess Plateau. The results showed that artificial vegetation restoration led to a significant increase in both SOC and TN content in the 0-100 cm soil profile compared with that of cropland. The highest increase in average SOC content was observed in the artificial woodland(1.43 times that of the cropland), followed by the artificial shrubland (1.36 times) and artificial grassland (1.21 times); whereas the highest increase in average TN content was observed in the artificial woodland (1.30 times that of the cropland), followed by the artificial grassland (1.21 times) and artificial shrubland (1.13 times). Compared with the cropland, there was a significant difference in SOC and TN content and fine root density up to a maximum depth of >100 cm in the artificial woodland and shrubland, but about 60 cm in the artificial grassland. The fine root density, soil C:N ratio and aboveground litter production of artificial woodland, shrubland and grassland were significantly higher than that of cropland, and fine root density was significantly linearly correlated with SOC and TN (P<0.01). The quantity and quality of fine root and litter biomass might be the dominant factors contributing to the observed difference in SOC and TN contents between the different artificial vegetation types in the Loess Plateau.

[Changes of Soil Organic Carbon and Its Influencing Factors of Apple Orchards and Black Locusts in the Small Watershed of Loess Plateau, China].

Orchard and black locust are two typical plants for comprehensive control in the small watershed of land uses in Loess area. The analysis of soil carbon sequestration function changes of growing two plants is important to gain a deep understanding of soil carbon cycle process and its influencing factors of terrestrial ecosystems under the condition of small watershed comprehensive control. The experiment was conducted in the Changwu State Key Agro-Ecological Station, Shanxi, China. SOC, TN, fine root biomass and litter amount were determined at different age apple orchards and black locusts on the slope land of Wangdonggou watershed to study the variation characteristics of soil organic carbon and its influencing factors under two measurements. The results showed that: (1) SOC and TN contents in apple orchards significantly decreased with the increased age, whereas those in black locust showed an increased tendency with the age increased. Compared with the adjacent cropland,the SOC and TN contents in year 3, year 8, year 12 and year 18 apple orchards were decreased 3. 26%, 10. 54%, 18. 08%, 22. 55% and - 8. 08%, - 0. 48%, 4. 97%, 16. 91%, respectively. However,SOC and TN contents increased 5. 31%, 32. 36%, 44. 13% and 2. 49%, 15. 75%, 24. 22%, in year 12, year 18 and year 25 black locusts, respectively. (2) The fine root biomass in year 3, year 8, year 12, and year 18 apple orchards were about 25. 97% 66. 23%, 85. 71% and 96. 10% of the adjacent cropland, respectively; and the litter amounts were all 0 g . m-2. However, compared with adjacent cropland, The fine root biomass in year 12, year 18 and year 25 black locusts were increased 23. 53%, 79. 41%, 157. 35%, respectively; and the litter input rates were 194, 298 , 433 g . (m2 . a) -1, respectively. (3) The difference of organic matter input was the major factor which drove the variability of soil carbon sequestration function of apple orchard and black locust ecosystems.

[Effects of Nitrogen Fertilization on Soil Respiration and Temperature Sensitivity in Spring Maize Field in Semi-Arid Regions on Loess Plateau].

Understanding the effects of nitrogen fertilization on soil respiration rate and its temperature sensitivity (Q10) is of critical importance to predict the variability of soil respiration in cropland. A field experiment was established in a rain-fed spring maize cropland (Zea mays L. ) in the State Key Agro-Ecological Experimental Station in the Loess Plateau in Changwu County, Shaanxi Province, China. The experiment comprised of two treatments: no N-fertilizer application ( CK) and N-fertilizer application with 160 kg N · hm(-2) (N). Soil respiration rate, soil temperature, soil moisture, yields, aboveground biomass and root biomass were measured in two continuous spring maize growing seasons from April 2013 to September 2014. The cumulative soil CO2 emissions were increased by 35% in 2013 and 54% in 2014 in N treatment as compared to CK treatment. Though nitrogen fertilization significantly increased the cumulative soil CO2 emissions (P < 0.05), it did decrease evidently the temperature sensitivity of soil respiration (P < 0.05) . The Q10 values in N treatment were decreased by 27% and 17% compared with CK treatment in 2013 and 2014, respectively. Nitrogen fertilization significantly increased the maize yields, aboveground biomass and root biomass (P < 0.05). Root biomasses in N treatment were 32% and 123% greater than those in CK treatment of 2013 and 2014, respectively. Nitrogen fertilization had no marked influence on soil temperature or moisture. Root biomass was a critical biotical factor for variation of soil respiration under nitrogen fertilization.

C1 lateral mass screw placement in occipitalization with atlantoaxial dislocation and basilar invagination: a report of 146 cases.

STUDY DESIGN: Retrospective study of 146 patients with the diagnosis of occipitalization, atlantoaxial dislocation (AAD) and basilar invagination, using a novel surgical treatment strategy. OBJECTIVE: To introduce a novel fixation and reduction technique. SUMMARY OF BACKGROUND DATA: Atlas occipitalization associated with basilar invagination often result in fixed AAD that need reduction and occipitocervical fixation. The widely used occipitocervical fixation with suboccipital screws has several limitations such as the poor screw purchase in maldevelopment of the occipital bone, limited area available for implants in previous suboccipital craniectomy. The placement of occipitalized C1 lateral mass screw is an alternative option. METHODS: From June 2007 to June 2013, 146 patients of occipitalized atlas with fixed AAD and basilar invagination, underwent fixation and reduction via C1 lateral mass and C2 pars/pedicle screw. RESULTS: A total of 143 patients achieved the follow-up in the range from 6 months to 4 years (average, 30 mo). Neurological improvement was seen in all the 143 patients, with the averaged Japanese Orthopedic Association scores increasing from 11.6 to 15.5. Radiographical evaluation showed that solid bony fusion was achieved in all patients, and complete reduction was attained in 95 patients, and partial reduction (>60%) in 40 patients, and no effective reduction in 8 patients who had additional transoral decompression. Magnetic resonance imaging demonstrated that the ventral cervicomedullary compression was relieved in all patients. CONCLUSION: Although technically demanding, the C1 lateral mass placement in occipitalization is very useful in the rescue situation where more conventional stabilization alternatives are not technically possible, or as routine occipitocervical stabilization. It provides firm stabilization offering an optimum situation for bony fusion, and meanwhile the effective reduction of fixed AAD and basilar invagination. An extremely high fusion rate can be expected with minimal complications and minimal postoperative immobilization with this technique.

[Variation characteristic in soil respiration of apple orchard and its biotic and abiotic influencing factors].

To evaluate the orchard variability of soil respiration and the response of soil respiration to its influencing factors is helpful for a deep understanding about the effects of converting cropland to apple orchard. A field experiment was conducted in the Changwu State Key Agro-Ecological Station. Soil respiration, soil temperature, soil moisture and roots biomasses were periodically measured in a mature apple orchard during 2011 and 2012. Soil respiration decreased as the distance from the trunk increased. The cumulative soil respiration in the 0.5 m-distance from the trunk was 20% and 31% higher than that in the 2 m-distance from the trunk, respectively in 2011 and 2012. The temperature sensitivity of soil respiration (Q10) was relatively lower in the 2 m-distance than that in the 0. 5 m-distance in both years. Soil temperature and soil moisture were slightly higher in the 2 m-distance, but there was no significant difference between the 2 m-distance and the 0. 5 m-distance. Soil respiration and soil temperature showed a significant exponential relationship, but there was no positive correlation between soil moisture and soil respiration. Soil temperature changes can explain seasonal variation of soil respiration well, but it could not explain its spatial variability. Root density was an important factor for the spatial variability of soil respiration and Q15. Variation of soil respiration coefficient was 23% -31%. Therefore, the distance from the trunk should be considered when estimating orchards soil respiration.

Posterior C1-C2 screw and rod instrument for reduction and fixation of basilar invagination with atlantoaxial dislocation.

PURPOSE: To report the surgical technique and preliminary clinical results for the treatment of basilar invagination (BI) with atlantoaxial dislocation (AAD) by posterior C1-C2 pedicle screw and rod instrument. METHODS: Between July 2012 and August 2013, 33 patients who had BI with AAD underwent surgery at our institution. Pre and postoperative three-dimensional computed tomographic (CT) scans were performed to assess the degree of dislocation. Magnetic resonance (MR) imaging was used to evaluate the compression of the medulla oblongata. For all patients, reduction of the AAD was conducted by two steps: fastening nuts and rods was performed to achieve the horizontal reduction. Distraction between C1 and C2 screws was performed to obtain the vertical reduction. RESULTS: No neurovascular injury occurred during surgery. Follow-up ranged from 6 to 15 months (mean 10.38 months) in 32 patients. Post-operative three-dimensional CT showed that complete horizontal reduction was obtained in 30/33 (90.9%), and complete vertical reduction was obtained in 31/33 (93.9%). The repeated three-dimensional CT and MR image demonstrated that bony fusion and the decompression of the medulla oblongata were obtained in all patients. Clinical symptoms improved significantly 3 months after surgery. CONCLUSIONS: This C1-C2 pedicle screw and rod instrument is a promising technique for the treatment of BI with AAD.

[Soil organic carbon storage changes with land reclamation under vegetation reconstruction on opencast coal mine dump].

Vegetation reconstruction was an effective solution to reclaim the opencast coal mine dump which was formed in the process of mining. To understand the impact of the vegetation reconstruction patterns' on the mine soil organic carbon (SOC) storage was essential for selecting the methods of vegetation restoration and also important for accurately estimating the potential of the soil carbon sequestration. The study area was on the Heidaigou opencast coal mine, which was 15 years reclaimed coal mine dump in Zhungeer, Inner Mongolia autonomous region, we selected 5 vegetation reconstruction patterns (natural recovery land, grassland, bush land, mixed woodland of arbor and bush, arbor land), and 16 vegetation types, 408 soil samples (0-100 m), to study the effect of the vegetation reconstruction patterns on the SOC storage. The results were showed as follows: (1) on the reclaimed coal mine dump, the vegetation reconstruction patterns significantly affected the SOC content and its distribution in the soil profile (P < 0.05). The surface 0-10 cm SOC content was grassland > shrub land > arbor forest > mixed forest of arbor and shrub > natural recovery land, in which the grassland, shrub land and arbor forest were about 2.2, 1.3, and 1.3 times of natural recovery land (2.14 g · kg(-1)) respectively. The total nitrogen (TN) showed the similar trends. (2) Among the vegetation types, Medicago sativa had the highest surface SOC content (5.71 g · kg(-1)) and TN content (0.49 g · kg(-1)), that were 171.3% and 166.7% higher than the natural recovery land, and two times of Hippophae rhamnoides, Amorpha fruticosa + Pinus tabulaeformis and Robinia pseudoacacia. (3) The effect of vegetation types on SOC mainly concentrated in the 0-20 cm depth, and the effect on TN accounted for 40 cm. (4) For the SOC storage, the order was original landform area > reclaimed dump > new dump and grassland > woodland (including arbor and shrub land). After 15 years revegetation, the soil carbon storage of the grassland, shrub land and arbor land were increased by 15.47 t · hm(-2), 6.93 t · hm(-2) and 6.95 t · hm(-2) respectively in the 100 cm depth, which were equivalent to 2/3, 1/2 and 1/2 of the original landform levels. The results showed a great ability of carbon sequestration.

[Differences in soil respiration between cropland and grassland ecosystems and factors influencing soil respiration on the Loess Plateau].

Understanding the effect of land-use change on soil respiration rates becomes critical in predicting soil carbon cycling under conversion of arable into grassland on the Loess Plateau. From July 2010 to December 2011, CO2 efflux from the soil surface was measured between 08:00 to 10:00 am in clear days by a Licor-8100 closed chamber system (Li-COR, Lincoln, NE, US). Also, soil temperature and soil moisture at the 5-cm depth was measured using a Li-Cor thermocouple and a hand-held frequency-domain reflectometer (ML2x, Delta-T Devices Ltd, UK) at each PVC collar, respectively. We found marked differences (P < 0.05) in soil respiration related to different land-use: the mean cropland soil respiration [1.35 micromol x (m2 x s)(-1)] was 24% (P < 0.05) less than the paired grassland soil respiration [1.67 micromol x (m2 x s)(-1)] (P < 0.05) during the period of experiment and the cumulative CO2-C emissions in grassland (856 g x m(-2)) was 23% (P < 0.05) higher than that in cropland (694 g x m(-2)). Soil moisture from 0-5 cm depth was much drier in cropland and significantly different between cropland and grassland except for winter. However, there were no clear relationships between soil moisture and soil respiration. Soil temperature at 5-cm depth was 2.5 degress C higher in grassland during the period of experiment (P < 0.05). Regression of soil temperature vs. soil respiration indicated significant exponential relationships both in grassland and cropland. Besides, there were intrinsic differences in response of soil respiration to temperature between the cropland and grassland ecosystems: grassland and cropland respiration response was significantly different at the alpha = 0.05 level, also expressed by a higher temperature sensitivity of soil respiration (Q10) in cropland (2.30) relative to grassland (1.74). Soil temperature of cropland and grassland can explain 79% of the variation in the soil respiration in grassland, compared to 82% in cropland. Therefore, land-use change can alter soil CO2 efflux under similar edaphic and climate conditions in the gully region of the Loess Plateau. The soil temperature difference between cropland and grassland can explain the soil respiration difference caused by land-use change, which was confirmed by the validation results.

[Effects of nitrogen fertilization, soil moisture and soil temperature on soil respiration during summer fallow season].

On the loess plateau, summer fallow season is a hot rainy time with intensive soil microbe activities. To evaluate the response of soil respiration to soil moisture, temperature, and N fertilization during this period is helpful for a deep understanding about the temporal and spatial variability of soil respiration and its impact factors, then a field experiment was conducted in the Changwu State Key Agro-Ecological Experimental Station, Shaanxi, China. The experiment included five N application rates: unfertilized 0 (N0), 45 (N45), 90 (N90), 135(N135), and 180 (N180) kg x hm(-2). The results showed that at the fallow stage, soil respiration rate significantly enhanced from 1.24 to 1.91 micromol x (m2 x s)(-1) and the average of soil respiration during this period [6.20 g x (m2 x d)(-1)] was close to the growing season [6.95 g x (m2 x d)(-1)]. The bivariate model of soil respiration with soil water and soil temperature was better than the single-variable model, but not so well as the three-factor model when explaining the actual changes of soil respiration. Nitrogen fertilization alone accounted for 8% of the variation soil respiration. Unlike the single-variable model, the results could provide crucial information for further research of multiple factors on soil respiration and its simulation.