[Effect of freeze-thaw cycles on aggregate breakdown of typical black soil during transportation]. / å†»èžå¯¹å ¸åž‹é»‘åœŸå›¢èšä½“è¾“ç§»ç ´ç¢Žç‰¹å¾çš„å½±å“.

During the snowmelt period, the external erosive forces are dominated by freeze-thaw cycles and snowmelt runoff. These forces may affect soil structure and aggregate stability, thereby influencing snowmelt erosion. The process of snowmelt runoff can lead to the breakdown of aggregates during their transportation. However, few studies examined the effects of freeze-thaw cycles on the breakdown of aggregates during transportation. Focusing on 5-7 and 3-5 mm soil aggregates of typical black soil region in Northeast China, we analyzed the composition of water-stable aggregates, mean weight diameter (MWD), normalized mean weight diameter (NMWD), as well as breakdown rate of soil aggregates (BR) under different freeze-thaw cycles (0, 1, 5, 10, 15 and 20 times) and different transport distances (5, 10, 15, 20, 25 and 30 m). We further investigated the contribution (CT) of both freeze-thaw cycles and transport distances to BR. The results showed that: 1) After freeze-thaw cycles, the 5-7 and 3-5 mm aggregates were mainly composed of particles with a diameter of 0.5-1 mm. With increasing frequency of freeze-thaw cycles, the MWD generally showed a downward trend. Moreover, under the same number of freeze-thaw cycles, the NMWD of 3-5 mm aggregates was higher than that of 5-7 mm aggregates. 2) As the transport distance increased, the BR of 5-7and 3-5 mm aggregates gradually increased. Compared that under control group, the BR under one freeze-thaw cycle increased by 59.7%, 32.2%, 13.7%, 6.2%, 13.4%, 7.5%, and 60.0%, 39.0%, 18.4%, 13.0%, 6.3%, 6.1% at the condition of 5, 10, 15, 20, 25 and 30 m transport distances, respectively. However, with increasing frequency of freeze-thaw cycles, the BR increased slowly. 3) The breakdown of soil aggregates was mainly influenced by the transport distance (CT=54.6%) and freeze-thaw cycles (CT=26.2%). Freeze-thaw cycles primarily altered the stability of soil aggregates, which in turn affected the BR. Therefore, during the snowmelt period, freeze-thaw cycles reduced the stability of soil aggregates, leading to severe breakdown of soil aggregates during snowmelt runoff process. This made the soil more susceptible to migration with snowmelt runoff, which triggered soil erosion. Therefore, more attention should be paid on the prevention of soil erosion during snowmelt period.

Comparison of the Clinical Outcomes between All-inside and Standard Technique in Anterior Cruciate Ligament Reconstruction with 6-strand Hamstring Tendon Autograft.

OBJECTIVE: All-inside and standard techniques with 4-strand hamstrings graft have been widely used in anterior cruciate ligament (ACL) reconstruction. However, the graft diameter of less than 8 mm will significantly increase the rate of surgical failure, and the 6-strand graft can solve this problem. The purpose of this study is to compare all-inside ACL reconstruction using suspensory cortical button fixation on both tibia and femur with standard ACL reconstruction using suspensory femoral fixation and a bioabsorbable tibial interference screw with a 6-strand hamstring tendon autograft in postoperative clinical outcomes. METHODS: From January 2020 to December 2020, 48 patients performed ACL reconstruction were divided into the all-side group and the standard group according to the different surgical techniques. Magnetic resonance imaging (MRI) and subjective function scores was used to assess clinical outcomes at least 24 months following ACL reconstruction. MRI was used to measure the value of bone tunnel widening in articular and middle portions. Subjective function scores included the Lysholm knee score, the International Knee Documentation Committee (IKDC) score, the Knee Society Score (KSS) for pain and function, and KT-1000. The t-test was used assuming the distribution of the patients which follows the normal distribution and we used non-parametric tests if these two conditions were not satisfied. RESULTS: At the final follow-up, there were 22 patients in the all-inside group and 24 patients in the standard group. No significant differences were found with respect to femoral tunnel widening and subjective function scores. However, a significant increase in tibial tunnel widening was found in the middle portion of the standard group (2.25 ± 0.74) compared to the all-inside group (0.76 ± 0.24) (p < 0.01) and also in the articular portion of the standard group (2.07 ± 0.77) compared to the all-inside group (1.52 ± 0.54) (p = 0.02). In addition, the value of the KT-1000 was 1.81 ± 0.45 for the all-inside group and 2.12 ± 0.44 in the standard group (p = 0.016). CONCLUSION: The objective stability of the knee was relatively better in the all-inside group than in the standard group. And tunnel widening after ACL reconstruction was significantly greater in the standard technique when compared to the all-inside technique on the tibia side.

Residual varus alignment after posterior-stabilized total knee arthroplasty limits medial soft tissue remodeling.

BACKGROUND: Proper lower limb alignment and soft tissue balance are significant indicators to measure the success of total knee arthroplasty (TKA). Previous studies have confirmed that soft tissue relaxation around the knee after TKA will change over time; however, the relationship between lower limb alignment and soft tissue balance after TKA remains unclear. We studied (1) whether the change of soft tissue balance around the knee with time after posterior-stabilized (PS) TKA would affect the alignment of the lower limbs; (2) Whether the accuracy of lower limb alignment during PS TKA affects postoperative soft tissue remodeling. METHODS: In this study, 100 patients were recruited after PS TKA. Among them, 50 patients with a hip knee ankle (HKA) angle of ≤ ± 3° were set as the neutral group, and 50 patients with an HKA angle of > ± 3° were set as the deviation group. The imaging results measured the HKA angle before the operation as well as the HKA, varus, and valgus angles at 1, 3, 6, 12, and 24 months after TKA. Clinical assessment included range of motion (ROM), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and Knee Society Score (KSS). RESULTS: Eight people were excluded from the study. After the exclusion, the study enrolled 47 patients in the neutral group and 45 patients in the deviant group and were followed for up to 2 years. There was no statistical significance in mean varus angles as well as HKA angle changes during the follow-up phase of each groups (P > 0.05). The mean valgus angles of the patients in the neutral group group were 2.47°, 3.45°, 3.63°, 3.60° and 3.63°, and in the deviation group were 2.45° (P = 0.841), 2.88° (P < 0.001), 3.07° (P < 0.001), 3.06° (P < 0.001), and 3.10° (P < 0.001). ROM, WOMAC and KSS of the two groups were significantly improved after operation, with no difference between the two groups. CONCLUSION: This study shows that whether the alignment is accurate or not in the early stage after TKA, the relaxation of the medial and lateral soft tissues of the knee joint change; however, this change will not significantly affect the alignment of the lower limbs. Postoperative residual varus deformity limits medial soft tissue remodeling. LEVEL OF EVIDENCE: III.

How Do the Morphological Abnormalities of Femoral Head and Neck, Femoral Shaft and Femoral Condyle Affect the Occurrence and Development of Medial Knee Osteoarthritis.

OBJECTIVE: At present, the main viewpoint is that tibial varus is the main reason of medial knee osteoarthritis (OA), and high tibial osteotomy (HTO) is also the main alignment correction method to correct medial knee OA. In contrast, the impact of the anatomical alignment of the femur on medial knee OA is often overlooked. We evaluated the increased risk for medial knee OA because a varus alignment could be attributed to the anatomical reasons that include hip anatomy, femoral shaft bowing (FSB) and femoral condylar dysplasia. METHODS: The present research adopted a cross-sectional study method. We selected 62 patients with HTO in the Third Hospital of Hebei Medical University from June 2021 to March 2022 as the HTO group and 55 healthy volunteers as the control group. Femoral neck-shaft angle (NSA), lateral FSB, mechanical lateral distal femoral angle (mLDFA) and hip-knee-ankle (HKA) was radiographically examined within the two groups. The femoral neck length and offset were also measured, and the ratio is represented by the ratio of the femoral neck length to off-set (N/O). The 2-tailed Student t-test was used to compare the differences between groups when the data were in accordance with a normal distribution. Otherwise, the Mann-Whitney U tests was used to compare the differences between groups. RESULT: Compared to the control group, the HTO group had a higher offset (p < 0.05), greater femoral neck length (p < 0.05), and decreased (more varus) NSA (p < 0.05). The HKA in the HTO group was 172.20 ° (3.50°), which was significantly lower than that of the control group 177.00° (3.05°), (p < 0.001), while the medial OA was associated with more varus HKA. The mean mLDFA was 89.10 ° (2.35°) and 87.50° (2.85°) in the HTO and control groups (p < 0.005), respectively. The mean lateral FSB values of the full-length radiographs were larger (p < 0.001) in the HTO group (4.24° ± 3.25°) than that in control group (1.16° ± 2.32°). CONCLUSION: The reduction of NSA (coxa vara) and the increase of the mLDFA can lead to medial knee OA, while the lateral FSB also affects medial OA. We believe that femoral deformity is also one of the cause of the medial knee OA. Therefore, it is necessary to evaluate the joint deformity of the femur and tibia before surgery in order to determine whether to use HTO alone to correct the lower limb alignment.

Spatial distribution characteristics of sediment connectivity and soil erosion in small watershed in brown soil hilly region of low mountains in western Liaoning Province, China.

Understanding the spatial distribution characteristics of soil erosion and sediment connectivity is important for formulating integrated watershed management measures. Based on the InVEST sediment delivery ratio model, we used the connectivity index and soil loss model to measure the spatial distribution characteristics of sediment connectivity and soil erosion in Erdaoling watershed of brown soil hilly region of low mountains in western Liaoning. By exploring slope, aspect and land use characteristics under different sediment connectivity levels and soil erosion levels, we analyzed the relationships among topography, land use, sediment connectivity, and soil erosion. The results showed that the average sediment connectivity in the watershed was -3.79, and that the average soil erosion was 614 t·km2·a-1. High connectivity was mainly found in sloping farmland, while low connectivity was mainly found in forest and grassland. The soil erosion intensity of 93.3% of the watershed area was below moderate, with only 1.1% of the area being above extremely strong. The higher the sediment connectivity level, the higher the proportion of the area <5° slope, while the area proportion of the rest slope was relatively stable. The proportion of cultivated land area increased, while the proportion of forest and grassland land area decreased. The area proportion on negative slope decreased, while that on positive slope increased. With increasing soil erosion intensity, the area proportion of slope <8° increased and the area proportion of the rest slope was relatively stable. The proportion of forest and grassland area decreased, while the proportion of other land use area increased. The proportion of slope area on positive slope increased, while that on negative slope decreased. Land use was a key factor influencing the spatial response relationship between soil erosion and sediment connectivity in this watershed.

Rice lipid transfer protein, OsLTPL23, controls seed germination by regulating starch-sugar conversion and ABA homeostasis.

Seed germination is vital for ensuring the continuity of life in spermatophyte. High-quality seed germination usually represents good seedling establishment and plant production. Here, we identified OsLTPL23, a putative rice non-specific lipid transport protein, as an important regulator responsible for seed germination. Subcellular localization analysis confirmed that OsLTPL23 is present in the plasma membrane and nucleus. The knockout mutants of OsLTPL23 were generated by CRISPR/Cas9-mediated genome editing, and osltpl23 lines significantly germinated slower and lower than the Nipponbare (NIP). Starch and soluble sugar contents measurement showed that OsLTPL23 may have alpha-amylase inhibitor activity, and high soluble sugar content may be a causal agent for the delayed seed germination of osltpl23 mutants. Transcript profiles in the germinating seeds exhibited that the abscisic acid (ABA)-responsive genes, OsABI3 and OsABI5, and biosynthesis genes, OsNCED1, OsNCED2, OsNCED3 and OsNCED4, are obviously upregulated in the osltpl23 mutants compared to NIP plants, conversely, ABA metabolism genes OsABA8ox1, OsABA8ox2 and OsABA8ox3 are stepwise decreased. Further investigations found that osltpl23 mutants displays weakened early seedling growth, with elevated gene expresssion of ABA catabolism genes and repressive transcription response of defence-related genes OsWRKY45, OsEiN3, OsPR1a, OsPR1b and OsNPR1. Integrated analysis indicated that OsLTPL23 may exert an favorable effect on rice seed germination and early seedling growth via modulating endogenous ABA homeostasis. Collectively, our study provides important insights into the roles of OsLTPL23-mediated carbohydrate conversion and endogenous ABA pathway on seed germination and early seedling growth, which contributes to high-vigor seed production in rice breeding.

Comparison of the Imaging and Clinical Outcomes among the Measured Resection, Gap Balancing, and Hybrid Techniques in Primary Total Knee Arthroplasty.

OBJECTIVE: Although many studies have compared the measured resection (MR) technique to the gap balancing (GB) technique, few studies have investigated the hybrid technique. In this study, we compared imaging and clinical outcomes of the MR, GB, and hybrid techniques in primary total knee arthroplasty (TKA). METHODS: From January 2016 to January 2019, we conducted a retrospective study on 90 patients who underwent unilateral primary TKA; 30 received the MR technique, 30 received the GB technique, and 30 received the hybrid technique. Radiological outcomes, including joint line level, mechanical alignment of the lower limb, positions of the femoral and tibial components, and rotation of the femoral component, and clinical outcomes, including the visual analog scale score for pain, the Knee Society Score, and the range of motion, were assessed among the three groups. One-way analysis of variance and Dunnett's test were performed for normally distributed data. Kruskal-Wallis H test and Dunn-Bonferroni test were conducted for non-normally distributed data. RESULTS: No significant difference in the mechanical alignment (p = 0.151) and the positions of the tibial and femoral components (p = 0.230 for α angle, p = 0.517 for ß angle, p = 0.686 for femoral flexion angle, and p = 0.918 for tibial slope angle) was found among the three groups. No significant difference in the elevation of the joint line between the MR and the hybrid groups was found (2.1 ± 0.3 mm vs 2.1 ± 0.1 mm, p = 0.627), but the GB group (2.8 ± 0.2 mm) differed significantly from the other two groups (p < 0.001). Although rotation of the femoral component in the GB group was larger than that of the MR and hybrid groups, the difference was not significant (1.8° ± 0.2° vs 1.7° ± 0.3° vs. 1.7° ± 0.2°, p = 0.101). The clinical outcomes were not significantly different (p > 0.05), although the results in the hybrid group were slightly higher. CONCLUSION: The hybrid technique helped to restore the mechanical alignment of the lower limb and realize optimal positions of the femoral and tibial components without significant differences relative to the MR and GB techniques. The hybrid technique was more helpful for maintaining the original height of the joint line, which was similar to the MR technique. Additionally, although the improvement in the clinical outcomes in the hybrid group was slightly higher, it was not significantly different among the three groups.

Distalization of tibial tubercle osteotomy is not necessary for patients with recurrent patellar dislocation accompanied by patella alta and increased TT-TG distance.

BACKGROUND: The aim of this study is to determine whether distalization of the tibial tubercle is necessary for patients with recurrent patellar dislocation accompanied by patella alta and increased TT-TG. METHODS: In this retrospective study, all 70 patients (70 knees) with recurrent patellar dislocation accompanied by TT-TG distance ≥20 mm and patella alta (CD-I ≥ 1.4) were surgically treated using MPFLR combined with medialization of the tibial tubercle or medialization and distalization of the tibial tubercle in the Third Hospital of Hebei Medical University between 2017 and 2019. 33 patients(33 knees) received MPFLR combined with medialization of the tibial tubercle (MPFLR + TTm group), 37 patients(37 knees) received MPFLR combined with medialization and distalization of the tibial tubercle (MPFLR + TTm-d group). Evaluation indicators included knee injury and osteoarthritis prognostic score (KOOS) and Kujala score evaluation, congruence angle (CA), patellar tilt angle (PTA), TT-TG distance, Blackburne-Peel index (BP-I), Caton-Deschamps index (CD-I). RESULTS: A total of 70 knees (70 patients) with a mean follow-up time of 32 ± 6 months were evaluated in the present study. The postoperative, the PTA, CA, CD-I, BP-I, and TT-TG distance significantly improved in the two groups (P < 0.05), and there was no statistical difference between the two groups (>0.05). The KOOS and Kujala scores of the two groups at the last follow-up were significantly higher than the preoperative scores (P < 0.05), and there was no statistical difference between the two groups (P>0.05). No complications were noted in either group. CONCLUSION: For patients with recurrent patellar dislocation accompanied by increased TT-TG distance and patella alta, distalization is not needed and medialization is sufficient even in the presence of patella alta.

Inducible Enrichment of Osa-miR1432 Confers Rice Bacterial Blight Resistance through Suppressing OsCaML2.

MicroRNAs (miRNAs) handle immune response to pathogens by adjusting the function of target genes in plants. However, the experimentally documented miRNA/target modules implicated in the interplay between rice and Xanthomonas oryzae pv. oryzae (Xoo) are still in the early stages. Herein, the expression of osa-miR1432 was induced in resistant genotype IRBB5, but not susceptible genotype IR24, under Xoo strain PXO86 attack. Overexpressed osa-miR1432 heightened rice disease resistance to Xoo, indicated by enhancive enrichment of defense marker genes, raised reactive oxygen species (ROS) levels, repressed bacterial growth and shortened leaf lesion length, whilst the disruptive accumulation of osa-miR1432 accelerated rice susceptibility to Xoo infection. Noticeably, OsCaML2 (LOC_Os03g59770) was experimentally confirmed as a target gene of osa-miR1432, and the overexpressing OsCaML2 transgenic plants exhibited compromised resistance to Xoo infestation. Our results indicate that osa-miR1432 and OsCaML2 were differently responsive to Xoo invasion at the transcriptional level and fine-tune rice resistance to Xoo infection, which may be referable in resistance gene discovery and valuable in the pursuit of improving Xoo resistance in rice breeding.

Determining optimal gestational weight gain (GWG) in a northwest Chinese population: A CONSORT.

ABSTRACT: To determine optimal gestational weight gain (GWG) for the Chinese population.Live singleton deliveries at the largest maternal & childcare hospital in northwest China from 2010 to 2012 were analyzed retrospectively. Multivariable logistic regression analysis was conducted to determine the lowest aggregated risk of interested perinatal outcomes based on Chinese adult body mass index (BMI) categories.Eight thousand eight hundred seventy enrolled parturients were divided into 4 groups according to their prepregnancy BMI: underweight (21.31%, BMI < 18.5 kg/m2), normal weight (67.81%, 18.5 kg/m2 ≤ BMI < 24 kg/m2), overweight (8.99%, 24 kg/m2 ≤ BMI < 28 kg/m2 and obese (1.89%, BMI ≥ 28 kg/m2). The optimal GWG values for the above 4 groups were 16.7 kg (GWG range, 12.0-21.5), 14.5 kg (9.5-19.5), 11.5 kg (7.0-16.5), and 8.0 kg (5.0-13.0). The rates of inadequate, optimal and excessive GWG in present study were 6.14% (545), 62.34% (5529), and 31.52% (2796) respectively, which were significantly different from those of the 2009 Institute of Medicine recommendation (χ2 = 1416.05, Pinteraction < 0.0001).Wider optimal GWG ranges than those recommended by Institute of Medicine were found in our study, and our proposed criteria seems to be practical to the Chinese population.

Medial Patellofemoral Ligament Reconstruction Using Suture Tape for Patellofemoral Joint Instability.

OBJECTIVE: To describe a surgical technique using suture tape for reconstruction of the medial patellofemoral ligament (MPFL). This technique restores the stability of the reconstructed ligament and has excellent postoperative outcomes. METHOD: This is a retrospective analysis. From January 2016 to June 2018, 17 patients underwent MPFL reconstruction using high-strength suture (FiberTape; Arthrex) augmentation, with at least 12 months of follow up. There were 11 female and 6 male patients. The mean age at the time of MPFL reconstruction was 22.1 years (range 13-34 years). Clinical outcomes included pain level, knee range of motion, passive patellar hypermobility, and maltracking at follow-up. The lateral patellofemoral angles, congruence angles, and patellar tilt angles were measured in a skyline view by CT at 30° of knee flexion at 12 months. Functional outcomes were assessed using the Lysholm knee scoring scale, the SF-12 score, the Tegner score, and the Crosby and Insall grading system at yearly follow-up. RESULT: No patients were lost at the last follow up. One patient had recurrence of patellar dislocation and none of the others had serious complications. The success rate of MPFL repair for preventing recurrent dislocations was 94.1% (16 of 17 knees). Fifteen knees had full range of motion of more than 130°. At follow-up, 2 knees were judged to have mild hypermobility and none had severe hypermobility or maltracking. Using the Crosby and Insall grading system, 12 knees (70.6%) were graded as excellent, 4 knees (23.5%) as good, 1 knee (5.9%) as fair to poor, and none as worse at the last follow-up assessment. In all patients, the Lysholm knee score (55.12 ± 13.52 vs 79.88 ± 7.50, P < 0.01), the SF-12 score (47 ± 9.53 vs 65.24 ± 12.82, P < 0.01), and the Tegner score (2.76 ± 1.39 vs 6.53 ± 1.70, P < 0.01) had improved at their 12-month follow up. Compared with preoperative radiological findings, there was a significant improvement in lateral patellofemoral angle (-10.24 ± 7.10 vs 6 ± 5.43, P < 0.01), patellar tilt angle (26.53 ± 7.23 vs 9.88 ± 4.24, P < 0.01), and congruence angle (29.59 ± 11.95 vs -8.65 ± 4.86, P < 0.01). CONCLUSION: The use of FiberTape in MPFL reconstruction can improve the stability of the knee following surgery and has good midterm clinical results and low complication rates.

Positive Guidance Effect of Ideological and Political Education Integrated With Mental Health Education on the Negative Emotions of College Students.

This exploration aims to solve the problems of imperfect psychological health education system and poor educational effects on college students. Here, ideological and political education is integrated with mental health education to investigate the role of collaborative intervention in guiding college students to resist negative emotions. First, an overview is offered of research on ideological and political education, mental health education, and negative emotions by the literature survey method. Moreover, a comprehensive investigation is also conducted on research objects, through the questionnaire, to understand the current situation of negative emotions of college students. And finally, an intervention experiment is taken on the negative emotions of college students by combining ideological and political education with mental health education. The results show that after 10 weeks of intervention experiment by combining ideological and political education with mental health education, there are significant differences in depression, negative emotions, somatization symptoms, and interpersonal problems between the treatment group and the control group (P < 0.01). Besides, there are significant differences in depression, negative emotions, somatization symptoms, and interpersonal problems between sophomores in the treatment group and the control group (P < 0.01). Moreover, there are significant differences in depression, negative emotions, somatization symptoms, and interpersonal problems between male participants in the treatment group and the control group (P < 0.01). In summary, ideological and political education integrated with mental health education has a positive guidance effect on the negative emotions of college students, greatly improving the negative emotions of the students, helping the students to regulate their emotions, and benefiting their study and life a lot. The purpose of integrating ideological and political education with mental health education is to provide reference for refining the mental health education system of college students and strengthening the positive guidance of negative emotions of college students.

Feasibility analysis of different surgical methods for uterine cesarean section scar diverticulum.

AIM: This study analyses the effects of surgical indicators and clinical efficacy of different surgical methods for uterine cesarean section scar diverticulum. METHODS: This retrospective cohort study included 65 patients who underwent surgery and postoperative follow-up at Gansu Provincial Maternity and Child-care Hospital from 1 January 2013 to 31 February 2019. RESULTS: All participants were treated surgically. Among them, patients in Group A underwent combined laparoscopic and hysteroscopic surgery (n = 45), Group B underwent transvaginal surgery (n = 11), Group C underwent laparotomy (n = 9). The primary outcomes were surgical indicators. The secondary outcomes were clinical efficacy. Bleeding, operation time and hospitalization expenses were significantly different among the three groups (P < 0.05). There was no difference in the hospital stay among the three groups P = 0.22). The menstrual period before and after surgery was significantly different among the groups (P < 0.05). The recurrence outcome was no significantly different (P = 0.16), but the pregnancy outcome was not (P = 0.78). CONCLUSION: The three surgical methods are effective for treating cesarean section scar diverticulum with favorable effects. Laparoscopic combined with hysteroscopic surgery is minimally invasive with less bleeding compared with the other two techniques and it is easier for patients to accept. It is the most widely used surgical method.

OsNPR3.3-dependent salicylic acid signaling is involved in recessive gene xa5-mediated immunity to rice bacterial blight.

Salicylic acid (SA) is a key natural component that mediates local and systemic resistance to pathogens in many dicotyledonous species. However, its function is controversial in disease resistance in rice plants. Here, we show that the SA signaling is involved in both pathogen-associated-molecular-patterns triggered immunity (PTI) and effector triggered immunity (ETI) to Xanthomonas oryzae pv. Oryzae (Xoo) mediated by the recessive gene xa5, in which OsNPR3.3 plays an important role through interacting with TGAL11. Rice plants containing homozygous xa5 gene respond positively to exogenous SA, and their endogenous SA levels are also especially induced upon infection by the Xoo strain, PXO86. Depletion of endogenous SA can significantly attenuate plant resistance to PXO86, even to 86∆HrpXG (mutant PXO86 with a damaged type III secretion system). These results indicated that SA plays an important role in disease resistance in rice plants, which can be clouded by high levels of endogenous SA and the use of particular rice varieties.

Characteristic Dissection of Xanthomonas oryzae pv. oryzae Responsive MicroRNAs in Rice.

MicroRNAs (miRNAs) are crucial player in plant-pathogen interaction. While the evidence has demonstrated that rice miRNAs mediate immune response to pathogens invasion, the roles of miRNAs on Xanthomonas oryzae pv. oryzae (Xoo) attack remain be in place. Herein, we monitored the responsive changes of rice miRNAs at 0, 8, 24 h across Xoo strain PXO86 infection in its compatible rice variety IR24 and incompatible variety IRBB5 by small RNA sequencing, and the genes targeted by miRNAs were also detected via degradome technology. The faithfulness of sequencing data was validated through quantitative real-time stem-loop reverse transcription-polymerase chain reaction assay. Bioinformatic analysis showed that the differentially expressed miRNAs could be divided into three immunity-related clusters, and 80 regulatory units were emerged in infection process, which comprises 29 differentially expressed known miRNAs and 38 cleaved targets. Furthermore, the miRNA presumptive function of separate immunity cluster in rice-Xoo interplay was confirmed through overexpressing osa-miR164a, osa-miR167d and osa-miR159b, and the disruption of regulatory units, osa-miR164a/OsNAC60, osa-miR167d-5p/OsWD40-174 and osa-miR159b/OsMYBGA, OsLRR-RLK2, OsMPK20-4, may reset rice defense response to Xoo infestation in a controllable manner. These findings provide new insights into the complex roles of characteristic miRNAs and their targets in rice-Xoo interactions.

Influence of Afforestation on the Species Diversity of the Soil Seed Bank and Understory Vegetation in the Hill-Gullied Loess Plateau, China.

The Chinese Loess Plateau region has long been suffering from serious soil erosion. Thus, large-scale afforestation has continued during the past decades in order to control soil erosion. Afforestation can dramatically alter nutrient cycles, affect soil-carbon storage, and change hydrology. However, it is unknown how afforestation influences species diversity of the soil seed bank and understory vegetation compared with spontaneous restoration of abandoned land. Forest land with trees planted 30 years ago, abandoned slope land restored spontaneously for 30 years, and the corresponding slopes with remnant natural vegetation were selected as sampling sites. The species richness both in the soil seed bank and vegetation was significantly higher on the afforested slope compared to the spontaneously restored abandoned land. The species similarity between the afforested slope and the remnant slope land was high both in the soil seed bank and standing vegetation compared to the abandoned land. The soil seed bank density varied from 1778 ± 187 to 3896 ± 221 seeds/m², and more than half of it was constituted by annual and biennial species, with no significant difference among sampling habitats. However, the afforested slope had higher seed density of grass and shrub/subshrubs compared to the abandoned slope. The present study indicates that in the study region, characterized by serious soil erosion, afforestation can better facilitate vegetation succession compared to spontaneously restoration of abandoned slope land.

Electroacupuncture Improved Hippocampal Neurogenesis following Traumatic Brain Injury in Mice through Inhibition of TLR4 Signaling Pathway.

The protective role of electroacupuncture (EA) treatment in diverse neurological diseases such as ischemic stroke is well acknowledged. However, whether and how EA act on hippocampal neurogenesis following traumatic brain injury (TBI) remains poorly understood. This study aims to investigate the effect of EA on hippocampal neurogenesis and neurological functions, as well as its underlying association with toll-like receptor 4 (TLR4) signaling in TBI mice. BrdU/NeuN immunofluorescence was performed to label newborn neurons in the hippocampus after EA treatment. Water maze test and neurological severity score were used to evaluate neurological function posttrauma. The hippocampal level of TLR4 and downstream molecules and inflammatory cytokines were, respectively, detected by Western blot and enzyme-linked immunosorbent assay. EA enhanced hippocampal neurogenesis and inhibited TLR4 expression at 21, 28, and 35 days after TBI, but the beneficial effects of EA on posttraumatic neurogenesis and neurological functions were attenuated by lipopolysaccharide-induced TLR4 activation. In addition, EA exerted an inhibitory effect on both TLR4/Myd88/NF-κB and TLR4/TRIF/NF-κB pathways, as well as the inflammatory cytokine expression in the hippocampus following TBI. In conclusion, EA promoted hippocampal neurogenesis and neurological recovery through inhibition of TLR4 signaling pathway posttrauma, which may be a potential approach to improve the outcome of TBI.

Association between toll-like receptor 4 expression and neural stem cell proliferation in the hippocampus following traumatic brain injury in mice.

Whether or how neural stem cells (NSCs) respond to toll-like receptor 4 (TLR4) in an inflammatory environment caused by traumatic brain injury (TBI) has not been understood. In the present study, association between TLR4 expression and NSCs proliferation in the hippocampus was investigated in a mouse model of TBI using controlled cortical impact (CCI). Hippocampal proliferating cells were labeled with the thymidine analog 5-bromo-2-deoxyuridine (BrdU). In order to identify NSCs, the proliferating cells were further co-labeled with BrdU/sex determination region of Y chromosome related high mobility group box gene 2 (SOX2). Morphological observation on the expression of BrdU, SOX2, and TLR4 in the hippocampus was performed by inmmunofluorescence (IF). Relative quantification of TLR4 expression at the protein and mRNA level was performed using Western blotting and real-time polymerase chain reaction (PCR). It was observed that BrdU+/SOX2+cells accounted for 95.80%±7.91% among BrdU+ cells; several BrdU+ cells and SOX2+ cells in the hippocampus were also TLR4-positive post injury, and that BrdU+ cell numbers, together with TLR4 expression at either protein or mRNA level, increased significantly in TBI mice over 1, 3, 7, 14, and 21 days survivals and changed in a similar temporal pattern with a peak at 3 day post-injury. These results indicate that hippocampal proliferating cells (suggestive of NSCs) expressed TLR4, and that there was a potential association between increased expression of TLR4 and the proliferation of NSCs post TBI. It is concluded that hippocampal TLR4 may play a potential role in endogenous neurogenesis after TBI.

Relationship between seedling and mature vegetation on the hilly-gullied Loess Plateau.

Seedling is an indispensable stage in plant cycle life, and seedling survival is important during natural vegetation restoration, especially on the Loess Plateau. In 2007, we selected 4 plots of Artemisia scoparia communities (ASC) and 4 plots of Artemisia gmelinii + Artemisia giraldii communities (AGC), examined seedling richness, diversity during the rainy season, and examined mature vegetation richness, coverage, and frequency in August. The results showed that seedlings density of ASC were 29 n m(-2), 33 n m(-2), 20 n m(-2) and 31 n m(-2) in July to October respectively, and that of AGC were 14 n m(-2), 12 n m(-2), 6 n m(-2) and 9 n m(-2) respectively; A. scoparia seedlings represented 53.2% of the total seedlings in ASC, the dominant species in AGC only account for less than 5% of the total seedlings. Most of the seedlings found were belonged to Compositae, Leguminoseae and Gramineae; 80% of seedlings in ASC were mainly comprised of A. scoparia and Lespedeza davurica, while in AGC that consisted of more than 6 species, such as L. davurica, Sophora viciifolia, Dracocephalum moldavicaand, A. gmelinii, Patrinia heterophylla, Heteropappus altaicus so on. Sørensen similarity index between monthly seedlings was approximately 0.47 in ASC and 0.35 in AGC; Sørensen similarity index between seedlings and mature vegetation ranged from 0.18 to 0.34 in ASC, and varied from 0.26 to 0.39 in AGC. These results suggested that seedling establishment would be a bottleneck for natural vegetation restoration when seed supply and seedling emergence were possible.

Seed morphology characteristics in relation to seed loss by water erosion in the Loess Plateau.

The role of water erosion on seed loss and on plant establishment and distribution is unknown on the Chinese Loess Plateau, which suffers serious soil erosion. The seed susceptibility of 16 local species to removal by water erosion from loess slopes was determined by rainfall simulation experiments. The experiments were performed on slopes with gradients of 10°, 15°, 20° and 25° for a 60-min duration at an intensity of 50 mm/h, 100 mm/h and 150 mm/h, respectively. The total seed removal rate obviously increased with rainfall intensity but did not obviously change with slope gradient, and the responses were varied among the species. The morphological characteristics affecting seed loss of the various species are quite different. Our experiments showed that the seed removal from some species are mainly due to seed weight, some species are mainly affected by seed shape, some are affected by appendage, some by surface structure, some by the comprehensive effects of the different morphological characteristics, while seeds having mucilage secretion are not easily moved by water erosion. We argued that the seed removal during water erosion can clearly effect seed redistribution and deposition, and consequently, species composition and vegetation spatial distribution.