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1.
Zhongguo Zhen Jiu ; 43(10): 1165-8, 2023 Oct 12.
Artigo em Chinês | MEDLINE | ID: mdl-37802523

RESUMO

The paper introduces professor ZHUANG Li-xing's clinical experience in treatment of dyskinesia of Parkinson's disease with acupuncture at triple-acupoint prescription. In pathogenesis, dyskinesia of Parkinson's disease refers to yang deficiency and disturbing wind. In treatment, acupuncture focuses on warming yang, promoting the circulation of the governor vessel, regulating the spirit and stopping trembling; and Baihui (GV 20), Suliao (GV 25) and Dingchanxue (Extra) are selected to be "trembling relief needling". In combination with Jin's three needling, named "three-trembling needling" "three-governor-vessel needling" and "three-spasm needling", the triple-acupoint prescription is composed. To ensure the favorable therapeutic effect, this prescription is modified according to the symptoms and the specific techniques of acupuncture are combined such as conducting qi, harmonizing yin and yang, and manipulating gently for reinforcing and reducing.


Assuntos
Terapia por Acupuntura , Acupuntura , Discinesias , Doença de Parkinson , Humanos , Pontos de Acupuntura , Doença de Parkinson/terapia , Terapia por Acupuntura/métodos
2.
Cureus ; 15(5): e39271, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37342752

RESUMO

Angelman syndrome (AS) is a rare pediatric neurological condition in which patients most commonly present with inappropriate laughter, microcephaly, speech difficulties, seizures, and movement disorders. AS can be diagnosed clinically and confirmed with genetic testing. In this case report, the patient presented with 9.3% weight loss at two days of age. Although there were multiple attempts at lactational counseling and nutritional guidance, the patient was admitted to the hospital due to failure to thrive. Due to continued global developmental delay and upper and lower extremities hypotonia by the age of nine months, the patient was referred to a neurologist. Brain MRI was negative, and genetic testing revealed 15q11.2q13.1 deletion, which is consistent with AS. Through different therapies and intervention, the patient showed slow improvements in symptoms. This case illustrates the importance of early recognition of nonspecific clinical manifestations of AS. The general management for all AS patients includes physical therapy, speech therapy, mobility support devices, education, and behavioral therapy as they progress through life. Establishing an early diagnosis has potential long-term benefits of improved quality of life and outcomes for patients via early interventions such as physical therapy starting at the age of six months to improve gross motor function. When infants present with nonspecific clinical presentations such as failure to thrive and hypotonia, clinicians should maintain a lower threshold for suspecting genetic conditions, which will facilitate early diagnosis of AS.

3.
Orthop Surg ; 15(6): 1571-1578, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37105902

RESUMO

OBJECTIVE: There has been no definite consensus on the ideal depth of acetabuloplasty, especially in cases of global pincer femoroacetabular impingement (FAI). This study aims to determine whether the depth of acetabuloplasty influences postoperative outcomes in cases of global pincer FAI. METHODS: Data were retrospectively collected from patients with global pincer FAI who underwent hip arthroscopy with a minimum follow-up period of 2 years from May 2014 to December 2018. Patients with global pincer FAI were subdivided into low or high resection depth groups based on whether the intraoperative acetabular rim was resected by more than 3 mm. Radiographic measurements; arthroscopic procedures; preoperative and postoperative PROs were recorded. Achievement of MCID and PASS was compared for the VAS, mHHS, HOS-ADL, and iHOT-12. A paired Student t-test was used to evaluate the significance of preoperative and postoperative PROs and two-tailed unpaired Student t-test was used to compare demographic data and PROs between different groups. MCID and PASS were evaluated using the chi-square test or the Fisher's exact test. RESULTS: A total of 41 hips with global pincer FAI (15 and 26 patients in low or high resection depth groups, respectively) were included in this study. Both groups showed significant postoperative improvements in the scores of all PROs (p < 0.001). Compared to the low resection depth group, the high resection depth group had a lower degree of improvement through hip arthroscopy, which manifested as lower postoperative mHHS scores (94.29 vs. 85.08, p = 0.006), higher VAS scores (0.93 vs. 2.54, p = 0.002), and lower improvements in VAS (-5.00 vs. -3.35, p = 0.028), HOS-ADL (34.99 vs. 23.90, p = 0.017) and iHOT-12 (39.89 vs. 29.27, p = 0.036). Patients in high resection depth group were less likely to achieve the MCID for the VAS score compared to low resection depth group in significant (73.3 vs. 26.9%, p = 0.004). CONCLUSIONS: For patients with global pincer, the outcomes in high resection depth group were slightly worse than the the low resection depth group. It is indicated that excessive resection of the acetabular rim during the procedure should be avoided.


Assuntos
Acetabuloplastia , Impacto Femoroacetabular , Humanos , Impacto Femoroacetabular/cirurgia , Articulação do Quadril/cirurgia , Seguimentos , Estudos Retrospectivos , Artroscopia/métodos , Resultado do Tratamento , Atividades Cotidianas
4.
J Anim Sci ; 1012023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36789882

RESUMO

Cat obesity has become a serious problem that affects cats' lives and welfare. Knowing how to control obesity in pet cats and its mechanism is urgently needed. Here, by feeding 30 cats different diets for 28 d, we explored the effects of 5 cat foods with potato, sweet potato, cassava, rice, and wheat as the main carbohydrate sources on the glycolipid metabolism of pet cats. The results showed that dietary carbohydrate sources did not affect the normal growth performance and stool scores of cats. Notably, we found that the starch gelatinization degree of sweet potato and cassava cat food were higher than those of other groups, while the rice diets had the highest digestibility, but the difference was not significant (P > 0.05). Furthermore, cats fed cassava diets had lower postprandial glucose responses. The mean glucose value, maximum glucose value, AUC0-360 min, AUC≤30 min, and AUC≥30 min in the cassava group were lower than those in other dietary groups (P > 0.05). In addition, we found that the carbohydrate source had a minimal effect on serum biochemical immune indices, but the blood lipid indices, such as TG, TC, HDL, and LDL of cats fed the cassava diet were maintained at a low level compared with other groups (P > 0.05). In addition, diets with different carbohydrate sources affect the gut microbial composition, and sweet potato and cassava diets tend to increase the diversity of gut microbiota with a higher Shannon index and Simpson index. The abundance of Fusobacterium, Veillonella, and Actinobacillus was significantly higher in sweet potato diet-fed cats (P < 0.05), while the abundance of Delftia, Shinella, Rothia, and Hydrogenophage was highest in cassava diet-fed cats (P < 0.05). Collectively, this study revealed that cassava and sweet potato diets have a better effect on feeding value, controlling blood glucose and blood lipids, and improving the intestinal flora of pet cats, which is worth developing dietary formulations to alleviate pet obesity.


Pet obesity is becoming increasingly common and may have a negative impact on pet health. The exploration of measures to alleviate pet obesity is urgently needed. Carbohydrates are an important component of pet food, and their digestion and absorption affect the levels of blood glucose and blood lipids and the procession of obesity. Therefore, the objective of this study was to evaluate the effects of different sources of carbohydrates on cat digestibility, postprandial glucose response, serum biochemical immune index, and microbiomes. The results showed that cat food with cassava and sweet potato as the main source of carbohydrates has a better effect on controlling blood glucose and blood lipids and improving the intestinal flora of pet cats. This provides a valuable reference for the research and development of pet food.


Assuntos
Doenças do Gato , Microbioma Gastrointestinal , Gatos , Animais , Glucose , Insulina , Ração Animal/análise , Dieta/veterinária , Obesidade/veterinária , Glicemia , Carboidratos da Dieta/análise , Digestão/fisiologia
5.
Arthroscopy ; 39(2): 285-292, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35367300

RESUMO

PURPOSE: To evaluate the clinical outcomes of hip arthroscopy for femoroacetabular impingement syndrome (FAIS) and their predictors at a minimum 5 years' follow-up. METHODS: We retrospectively analyzed patients with FAIS after first-time unilateral hip arthroscopy between January 2010 and July 2016. Patient-reported outcomes (PROs) included the validated modified Harries Hip Score (mHHS) and Visual Analog Scale for Pain (Pain VAS). We included patients with Tönnis grade 0 or 1 and reported PROs, and excluded patients with previous hip diseases or bilateral symptoms. Bivariate and multivariate analyses were used for data analysis. RESULTS: We included 159 patients with a mean follow-up of 6.4 years, aged 36.18 ± 8.61 years, 41.5% female, and a mean body mass index of 23.61 ± 3.45. The mean postoperative mHHS was 88.82 ± 11.60, and the mean Pain VAS was 1.93 ± 1.89, significantly better than before surgery (P < .001). Postoperative alpha angle (P = .003) and lateral center edge angle (P < .001) were significantly decreased. Most patients (83.7%) achieved clinically important improvement based on patient-acceptable symptom state and minimal clinically important difference (MCID). The overall revision surgery rate was 2.5%. There were no conversions to total hip arthroplasty. Bivariate analysis indicated that age (P < .001), preoperative mHHS (P = .002), and postoperative Pain VAS (P <.001) correlated with postoperative mHHS at a minimum 5 years' follow-up. Multivariate regression analysis of MCID showed that age (P <.001), preoperative PROs (P < .01 for both), and postoperative Pain VAS (P < .001) were significant outcome predictors. CONCLUSION: Patients with FAIS after first-time unilateral hip arthroscopy showed significant improvement in PROs at mid-term follow-up, with a low revision surgery rate. Young patients and those with low postoperative Pain VAS showed excellent outcomes at a minimum 5 years' follow-up. LEVEL OF EVIDENCE: Level IV, retrospective case series.


Assuntos
Impacto Femoroacetabular , Humanos , Feminino , Masculino , Impacto Femoroacetabular/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Artroscopia , Dor Pós-Operatória , Medidas de Resultados Relatados pelo Paciente , Atividades Cotidianas , Articulação do Quadril/cirurgia , Seguimentos
6.
Zhongguo Zhen Jiu ; 42(12): 1351-6, 2022 Dec 12.
Artigo em Chinês | MEDLINE | ID: mdl-36484186

RESUMO

OBJECTIVE: To observe the clinical efficacy of Tiaohe Yinyang acupotomy (acupotomy for regulating and harmonizing yin and yang) for knee osteoarthritis (KOA). METHODS: A total of 88 patients with KOA were randomized into a acupotomy group and a sham-acupotomy group, 44 cases in each group. In the acupotomy group, acupotomy was applied at yin side (4-5 high stress points i.e. pes anserinus and terminal of popliteus) and yang side (1-2 high stress points i.e. stimulation point of infrapatellar ligament and suprapatellar bursa) of knee joint. In the sham-acupotomy group, sham-acupotomy was applied at the same points as the acupotomy group. The treatment was given once a week for 2 weeks in the two groups. Before and after treatment, the Western Ontario and McMaster Universities arthritis index (WOMAC) score, visual analogue scale (VAS) score, thickness of medial and lateral collateral ligaments of knee joint, motion range of knee joint and plantar pressure distribution were observed in the two groups. In the follow-up of 3 months after treatment, the WOMAC and VAS scores were recorded in the acupotomy group. RESULTS: After treatment, the sub item scores (pain, stiffness and function) and total scores of WOMAC and VAS scores were decreased in the both groups (P<0.05), pain score, function score and total score of WOMAC and VAS score in the acupotomy group were lower than those in the sham-acupotomy group (P<0.05). Before and after treatment, there were no statistical differences in thickness of medial and lateral collateral ligaments of knee joint and motion range of knee joint between the two groups (P>0.05). After treatment, the plantar medial pressure was increased while the plantar lateral pressure was decreased (P<0.05), and the plantar force line moved medially in the acupotomy group. In the follow-up, the sub item scores and total score of WOMAC and VAS score were lower than those before and after treatment in the acupotomy group (P<0.05). CONCLUSION: Tiaohe Yinyang acupotomy can improve the clinical symptoms of knee joint in patients with KOA by changing the local biological stress.


Assuntos
Dor , Humanos
7.
Clin J Sport Med ; 32(6): 608-616, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36315820

RESUMO

OBJECTIVE: The objective of this review was to analyze the effect of arthroscopic surgery for femoroacetabular impingement syndrome (FAI) in adolescents and factors that may influence the revision rate. DESIGN: Systematic review and meta-analysis. SETTING: PubMed, Scopus, Cochrane Library, EMBASE, and MEDLINE were searched from their earliest records to May 2021. PATIENTS: Adolescents who underwent primary arthroscopic treatment for FAI. INTERVENTIONS: Hip arthroscopic treatment. MAIN OUTCOME MEASURES: Patient-reported outcomes (PROs), alpha angle, revision rates, and the rate of complications. RESULTS: A total of 832 hips in 753 patients were included in this study. All PROs improved significantly. The modified Harris Hip Score pooled mean difference was 24.99 (95% CI, 22.88-27.10, P < 0.0001, I2 = 19.9%), Hip Outcome Score (HOS)-Sports-Specific Subscale was 35.88 (95% CI, 33.07-38.68, P < 0.0001, I2 = 0%), HOS-Activities of Daily Living was 23.53 (95% CI, 21.21-25.85, P < 0.0001, I2 = 0%), and the Nonarthritic Hip Score was 22.34 (95% CI, 18.40-26.28, P < 0.0001, I2 = 40.9%). The visual analog scale for pain decreased by 40.39 (44.39-36.40, P < 0.0001, I2 = 0%). The alpha angle decreased by 22.0 degrees from 62.9 degrees to 40.9 degrees after arthroscopic surgery. The rate of complication and revision surgery was 1.2% (10/832) and 3.4% (28/832), respectively, with high postoperative patient satisfaction. CONCLUSIONS: All PROs significantly improved after surgery, with a low rate of complications and reoperation. High postoperative patient satisfaction was also reported.


Assuntos
Impacto Femoroacetabular , Humanos , Adolescente , Impacto Femoroacetabular/cirurgia , Atividades Cotidianas , Articulação do Quadril/cirurgia , Resultado do Tratamento , Artroscopia , Seguimentos
8.
International Eye Science ; (12): 1411-1416, 2022.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-935024

RESUMO

AIM: To understand the status of poor vision and analyze the main influencing factors among primary and secondary school students in a division of the Xinjiang Production and Construction Corps, and provide a scientific basis for prevention and control of poor vision.METHODS: A total of 12 primary and secondary schools in a divisional urban district and regiment field of the Xinjiang Production and Construction Corps were chosen using stratified cluster random sampling from August to October 2020. A total of 2 982 primary and secondary school students were selected for visual inspections and questionnaires. Logistic regression analysis was used to explore the influencing factors of poor vision.RESULTS: The rate of poor vision was 65.66% among 2 982 primary and secondary school students in the division of the Xinjiang Production and Construction Corps, with the majority severe poor vision. Furthermore, the rates of poor vision were higher in girls(70.17%)than that in boys(61.47%)(χ2=4.993, P<0.001)and the urban area(70.03%)were higher than the rural area(58.96%)(χ2=38.680, P<0.001)and the Han nationality students(66.83%)were higher than Uyghur students(52.82%)(χ2=19.772, P<0.001). The risk of poor vision increased with age(χ2trend =300.144, P<0.001), and by the age group ≥18 years old, the rate of poor vision reached 80.47%. The results of the multivariate analysis showed that the women, the age≥13 years old, writing and reading duration every day ≥2h, cram school on weekends and presence of myopia in parents increases the risk of poor vision, increase the outdoor exercise time, sleep time ≥8h, and do eye exercises every day can reduce the occurrence of poor vision.CONCLUSION: Poor vision rate of primary and secondary school students in the division of the Xinjiang Production and Construction Corps is higher than that of many regions in the country. Girls with the age(≥13 years old)whose parents are myopic should receive special attention. Increasing outdoor exercise time, doing eye exercises every day, and keeping your eyes more than one foot away from books when reading and writing is effective in preventing poor vision.

9.
ACS Omega ; 6(39): 25772-25781, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34632233

RESUMO

The molecular structure model of lignite was constructed, and the dissociation and removal mechanism of different C-O bonds and oxygen-containing functional groups was investigated using density functional theory (DFT) calculations. First, the bond order and bond dissociation enthalpy (BDE) were analyzed to predict the strength of different chemical bonds, and differences in the BDE and bond order were related to the difference in the fragment structure and electronic effects. The first group to break during hydrothermal carbonization (HTC) is the methyl of Ph(CO)O-CH3, followed by the C-O of CH3-OC(O)OH; the hydroxyl in Ph-OH is the most thermally stable group, followed by the hydroxyl in CH3OC(O)-OH. In addition, the orbital localization analysis has also been carried out. All three chemical bonds of Ph(CO)OCH3 show the characteristics of σ bond, while Ph(C=O)OCH3 and Ph(CO)-OCH3 with the Mayer bond order (MBO) greater than 1 also contains certain π bond characteristics. The lignite van der Waals (vdW) surface electrostatic potential (ESP) was constructed and visualized, and the results showed that the oxygen-containing functional groups mainly contributed to the area with a large absolute ESP. Finally, weak interactions between water molecules and lignite at different sites were described by independent gradient model (IGM) analysis. Models A, B, and E formed weak interactions with the hydrogen bond as the main force; model E showed the weakest hydrogen bond, while model C showed van der Waals interaction as the dominant force. In addition, some steric effect was also observed in model D.

10.
ACS Omega ; 6(31): 20166-20180, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34395968

RESUMO

Basic property analysis is the most comprehensive evaluation of metallurgical characteristics of blast furnace injection fuel. In this study, the basic properties of 16 types of pyrolysis biomass char samples were comprehensively investigated; the results showed that components harmful to a blast furnace, such as the ash content and alkali metal content of Jiangsu Suzhou woodblock char (B3), Jiangsu Changzhou branch char (B8), Jiangsu Zhangjiagang bamboo char (B10), and Jiangsu Zhangjiagang coconut shell char (B12) in all of the biomass char samples, are lower and close to the level of blast furnace injection bituminous coal. The grindability, particle size distribution, and safety all met the requirements of the blast furnace. Among them, the ash melting characteristic temperature of B3, B8, Jiangsu Zhangjiagang rice husk char (B11), and Shanghai soil remediation agent (B16) was greater than 1250 °C, indicating that they are not easy to block the blast furnace raceway and spray guns. Most of the biomass char samples had good combustibility, and the burnout temperature was less than 700 °C. A self-developed blast furnace injection combustion simulation experimental device was used to simulate the combustion behavior of biomass char in the blast furnace raceway tuyere, and the burnout rates of 16 biomass chars were measured. The results showed that that the burnout rate is related to both the volatiles and fixed carbon and the influence of volatiles on the burnout rate is greater than that of fixed carbon. The burnout rates of B3 and B8 were 77.12 and 67.03%, respectively. Above all, B3 and B8 showed good properties, but the burnout rate of B3 was higher, so B3 had the feasibility of applying to blast furnace injection, which indicates that woodblock char has the potential to be used as blast furnace injection fuel.

11.
Zhen Ci Yan Jiu ; 45(6): 513-6, 2020 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-32643891

RESUMO

The therapeutic effect of acupuncture is often closely related to the improvement of microcirculation. Acupuncture stimulation can adjust pathophysiological changes of microcirculation in the human body through multiple ways, multiple links and multiple levels, healing disorders at last. Laser speckle contrast imaging (LSCI), an emerging technology, can be used to study the effect of acupuncture on microcirculation. In this paper, retrieving the related literature published in recent years, we found that LSCI technology has already been applied to the following aspects 1) acupoint-viscera and microcirculation, 2) stimulation-induced transmission of sensations along the meridian and microcirculation, 3) non-meridians or non-acupoints and microcirculation, 4) specific acupoints and microcirculation, as well as 5) different acupuncture needle manipulations and microcirculation. However, most of the studies focused on animal experiments and healthy subjects, observing microcirculatory effects under normal physiological conditions, and the sample size of participants was smaller. In the future, we highly recommend that increasing the sample size and further studying the local microcirculation are necessary in the pathological state of diseases.


Assuntos
Terapia por Acupuntura , Microcirculação , Animais , Humanos
12.
Zhongguo Zhen Jiu ; 40(2): 193-6, 2020 Feb 12.
Artigo em Chinês | MEDLINE | ID: mdl-32100507

RESUMO

OBJECTIVE: To objectively evaluate the safety of acupoint catgut embedding therapy. METHODS: A total of 331 patients who received acupoint catgut embedding therapy were enrolled and summarized through the inpatient medical record system, follow-up record and adverse reaction report card. The statistical analysis was performed from the aspects of patients' gender, age, marital status, history of allergy, history of diabetes and the time, symptoms, duration and prognosis of adverse reactions, etc. RESULTS: Among 331 patients who received acupoint catgut embedding therapy, 70 patients had adverse reactions, which were divided into 9 types, including post-treatment discomfort, local hematoma or subcutaneous hemorrhage, local swelling, local induration, severe pain, thread-body rejection, local pruritus, post-treatment body temperature rising, local redness, swelling, fever and pain. The incidence rate of adverse events was 21.15%, and the incidence of serious adverse events was 0. Among the patients with adverse reactions, 58 patients (82.86%) relieved without treatment, and 12 patients (17.14%) received after symptomatic treatment; all patients had no sequelae. CONCLUSION: The acupoint catgut embedding therapy is relatively safe and the incidence of adverse reactions is low.


Assuntos
Terapia por Acupuntura/efeitos adversos , Categute/efeitos adversos , Pontos de Acupuntura , Febre , Humanos , Dor
13.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-793029

RESUMO

OBJECTIVE@#To objectively evaluate the safety of acupoint catgut embedding therapy.@*METHODS@#A total of 331 patients who received acupoint catgut embedding therapy were enrolled and summarized through the inpatient medical record system, follow-up record and adverse reaction report card. The statistical analysis was performed from the aspects of patients' gender, age, marital status, history of allergy, history of diabetes and the time, symptoms, duration and prognosis of adverse reactions, etc.@*RESULTS@#Among 331 patients who received acupoint catgut embedding therapy, 70 patients had adverse reactions, which were divided into 9 types, including post-treatment discomfort, local hematoma or subcutaneous hemorrhage, local swelling, local induration, severe pain, thread-body rejection, local pruritus, post-treatment body temperature rising, local redness, swelling, fever and pain. The incidence rate of adverse events was 21.15%, and the incidence of serious adverse events was 0. Among the patients with adverse reactions, 58 patients (82.86%) relieved without treatment, and 12 patients (17.14%) received after symptomatic treatment; all patients had no sequelae.@*CONCLUSION@#The acupoint catgut embedding therapy is relatively safe and the incidence of adverse reactions is low.

14.
Front Microbiol ; 10: 895, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31105679

RESUMO

In the context of secondary forest succession, aboveground-belowground interactions are known to affect the dynamics and functional structure of plant communities. However, the links between soil microbial communities, soil abiotic properties, plant functional traits in the case of semi-arid and arid ecosystems, are unclear. In this study, we investigated the changes in soil microbial species diversity and community composition, and the corresponding effects of soil abiotic properties and plant functional traits, during a ≥150-year secondary forest succession on the Loess Plateau, which represents a typical semi-arid ecosystem in China. Plant community fragments were assigned to six successional stages: 1-4, 4-8, 8-15, 15-50, 50-100, and 100-150 years after abandonment. Bacterial and fungal communities were analyzed by high-throughput sequencing of the V4 hypervariable region of the 16S rRNA gene and the internal transcribed spacer (ITS2) region of the rRNA operon, respectively. A multivariate variation-partitioning approach was used to estimate the contributions of soil properties and plant traits to the observed microbial community composition. We found considerable differences in bacterial and fungal community compositions between the early (S1-S3) and later (S4-S6) successional stages. In total, 18 and 12 unique families were, respectively, obtained for bacteria and fungi, as indicators of microbial community succession across the six stages. Bacterial alpha diversity was positively correlated with plant species alpha diversity, while fungal diversity was negatively correlated with plant species diversity. Certain fungal and bacterial taxa appeared to be associated with the occurrence of dominant plant species at different successional stages. Soil properties (pH, total N, total C, NH4-N, NO3-N, and PO4-P concentrations) and plant traits explained 63.80% and 56.68% of total variance in bacterial and fungal community compositions, respectively. These results indicate that soil microbial communities are coupled with plant communities via the mediation of microbial species diversity and community composition over a long-term secondary forest succession in the semi-arid ecosystem. The bacterial and fungal communities show distinct patterns in response to plant community succession, according to both soil abiotic properties and plant functional traits.

15.
Front Plant Sci ; 9: 180, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29497437

RESUMO

Species respond to changes in their environments. A core goal in ecology is to understand the process of plant community assembly in response to a changing climate. Examining the performance of functional traits and trait-based assembly patterns across species among different growth forms is a useful way to explore the assembly process. In this study, we constructed a habitat severity gradient including several environment factors along a 2300 m wide elevational range at Taibai Mountain, central China. Then we assessed the shift on functional trait values and community assembly patterns along this gradient across species among different growth forms. We found that (1) although habitat-severity values closely covaried with elevation in this study, an examined communities along a habitat severity gradient might reveal community dynamics and species responses under future climate change. (2) the occurrence of trait values along the habitat severity gradient across different growth forms were similar, whereas the assembly pattern of herbaceous species was inconsistent with the community and woody species. (3) the trait-trait relationships of herbaceous species were dissimilar to those of the community and woody species. These results suggest that (1) community would re-assemble along habitat severity gradient through environmental filtering, regardless of any growth forms and that (2) different growth forms' species exhibiting similar trait values' shift but different trait-trait relationship by different trait combinations.

16.
Sci Total Environ ; 621: 245-252, 2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-29182967

RESUMO

Leaf economics and hydraulic traits are simultaneously involved in the process of trading water for CO2, but the relationships between these two suites of traits remain ambiguous. Recently, Li et al. (2015) reported that leaf economics and hydraulic traits were decoupled in five tropical-subtropical forests in China. We tested the hypothesis that the relationships between economics and hydraulic traits may depend on water availability. We analysed five leaf economics traits, four hydraulic traits and anatomical structures of 47 woody species on the Loess Plateau with poor water availability and compared those data with Li et al. (2015) obtained in tropical-subtropical regions with adequate water. The results showed that plants on the Loess Plateau tend to have higher leaf tissue density (TD), leaf nitrogen concentrations and venation density (VD) and lower stomatal guard cell length (SL) and maximum stomatal conductance to water vapour (gwmax). VD showed positive correlations with leaf nitrogen concentrations, palisade tissue thickness (PT) and ratio of palisade tissue thickness to spongy tissue thickness (PT/ST). Principal component analysis (PCA) showed a result opposite from those of tropical-subtropical regions: leaf economics and hydraulic traits were coupled on the Loess Plateau. A stable correlation between these two suites of traits may be more cost-effective on the Loess Plateau, where water availability is poor. The correlation of leaf economics and hydraulic traits may be a type of adaptation mechanism in arid conditions.


Assuntos
Florestas , Folhas de Planta/fisiologia , Árvores/fisiologia , Água/fisiologia , China
17.
J Org Chem ; 69(23): 8108-10, 2004 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-15527298

RESUMO

A variety of aminoalkynes and related heterocycles are reacted in the Bronsted superacid CF(3)SO(3)H (triflic acid), and products are obtained in generally good yields (69-99%) from Friedel-Crafts-type reactions. The reactions are consistent with the formation of novel dicationic intermediates having a vinyl cationic site and an adjacent protonated N-heterocycle or ammonium cation.


Assuntos
Alcinos/química , Aminas/química , Compostos Heterocíclicos/química , Catálise , Cátions/química , Indicadores e Reagentes , Estrutura Molecular , Compostos de Amônio Quaternário/química
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