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1.
Nat Commun ; 12(1): 19, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33397992

RESUMO

Amines are a class of compounds of essential importance in organic synthesis, pharmaceuticals and agrochemicals. Due to the importance of chirality in many practical applications of amines, enantioselective syntheses of amines are of high current interest. Here, we wish to report the development of (R,Ra)-N-Nap-Pyrinap and (R,Sa)-N-Nap-Pyrinap ligands working with CuBr to catalyze the enantioselective A3-coupling of terminal alkynes, aldehydes, and amines affording optically active propargylic amines, which are platform molecules for the effective derivatization to different chiral amines. With a catalyst loading as low as 0.1 mol% even in gram scale reactions, this protocol is applied to the late stage modification of some drug molecules with highly sensitive functionalities and the asymmetric synthesis of the tubulin polymerization inhibitor (S)-(-)-N-acetylcolchinol in four steps. Mechanistic studies reveal that, unlike reported catalysts, a monomeric copper(I) complex bearing a single chiral ligand is involved in the enantioselectivity-determining step.


Assuntos
Aminas/química , Aminas/síntese química , Teoria da Densidade Funcional , Ligantes , Rotação , Estereoisomerismo
2.
Chemosphere ; 262: 127828, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32763579

RESUMO

Cadmium (Cd) pollution is a widespread environmental problem that decreases crop production, destroys the microbial ecology of soil, and poses a severe risk to human health. Organo-chemical amendment is a cost-effective, eco-friendly, and community-acceptable widely applied an in situ technique for metal-contaminated farmland. In this study, we mixed lime, zeolite, calcium magnesium phosphate fertilizer, and biochar in a mixture ratio of 71:23:5:1 to form a mixed amendment. Field and laboratory experiments were conducted to study the effects of the mixed amendment on soil exchangeable Cd content, plant Cd accumulation, and soil microbial community. It was found that the application of 0.5% mixed amendment decreased exchangeable soil Cd by more than 85% and 64% in wheat and rice season, respectively, compared with control (CK), without increasing pH. Moreover, the application of 0.5% mixed amendment decreased Cd accumulation in grains by 22.9% and 41.2% in wheat and rice season, respectively, compared to CK. The result of phospholipid fatty acids (PLFAs) shows that the level of soil microbial diversity and species richness under mixed amendment treatments were higher than in lime treatment, indicating more copiotrophic conditions and faster rate of nutrient turnover in mixed amendment than pure lime treatment. Hence, it concluded that the mixed amendment has a strong effect on fixing exchangeable soil Cd and reducing the accumulation of Cd in crops. Finally, it was observed that the mixed amendment improved the soil microbial community structure and accelerate the rate of nutrient turnover by microbes under this favorable condition comparative to individual treatments.


Assuntos
Cádmio/química , Microbiota/efeitos dos fármacos , Microbiologia do Solo , Poluentes do Solo/química , Agricultura/métodos , Cádmio/análise , Cádmio/toxicidade , Compostos de Cálcio , Carvão Vegetal , Produtos Agrícolas , Poluição Ambiental , Recuperação e Remediação Ambiental/métodos , Fertilizantes , Humanos , Microbiota/fisiologia , Oryza/efeitos dos fármacos , Óxidos , Fosfatos , Rotação , Solo/química , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Triticum
3.
J Endod ; 47(1): 88-93, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32961213

RESUMO

INTRODUCTION: This study aimed to compare the torsional resistances and fracture modes of WaveOne Gold (Dentsply Sirona, Ballaigues, Switzerland) and Reciproc Blue (VDW, Munich, Germany) using the repetitive torsional loading (RTL) method and the conventional single-rotation (STL) method. METHODS: A 3-mm file tip was fixed with a brass plate, and a torsional load was applied using a custom device. In the RTL method, the file was driven counterclockwise at 50 rpm until it achieved the preset torque of 0.5 Ncm; thereafter, it was returned to its original position. This recovery of the file to its original position was defined as 1 torsional loading cycle; the number of repetitive load cycles until fracture was counted. In the STL method, the files were rotated at a constant rate of 2 rpm in a counterclockwise direction until file fracture. The fragments fractured by the 2 methods were compared under a scanning electron microscope to examine the topographic features of the fractured surfaces and longitudinal aspects. RESULTS: With the RTL method, Reciproc Blue showed a higher number of repetitive load cycles until fracture than WaveOne Gold (P < .05). With the STL method, Reciproc Blue also had a higher ultimate strength than WaveOne Gold (P < .05). Scanning electron microscopic findings of the fractured specimens from the 2 test methods showed different features of torsional failure. CONCLUSIONS: Within the study limitations, both the RTL and STL methods conferred similar torsional resistance. Therefore, the clinically relevant RTL method with repetitive and reciprocation motion can be used for testing torsional resistance.


Assuntos
Ouro , Preparo de Canal Radicular , Instrumentos Odontológicos , Desenho de Equipamento , Alemanha , Teste de Materiais , Rotação , Titânio , Torque
4.
J Endod ; 47(1): 94-99, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33002538

RESUMO

INTRODUCTION: This study aimed to analyze torque/force generation and transportation in double-curved canals instrumented with 3 types of glide path files using optimum glide path (OGP) motion in comparison with continuous rotation. METHODS: Sixty simulated double-curved canals were prepared with #10/0.05 or #15/0.03 HyFlex EDM Glidepath files (Coltene/Whaledent, Altstätten, Switzerland) or a #13/0.04 prototype MANI Glidepath file (Tochigi, Japan) using OGP motion or continuous rotation (n = 10 each). Canals were sequentially prepared to 20 mm and 22 mm (full working length) using automated root canal instrumentation and a torque/force analyzing device. Transportation was calculated at 1-9 mm from the apex. Data were compared using 2-way analysis of variance followed by a post hoc simple main effect test with Bonferroni correction and a Kruskal-Wallis test (α = 5%). RESULTS: All #10/0.05 instruments fractured. In the 22-mm preparation, the OGP motion resulted in lower clockwise torque and screw-in force than did continuous rotation (P < .05). In the 20-mm preparation, #15/0.03 instruments recorded a lower screw-in force for OGP motion than for continuous rotation (P < .05). Comparing the 2 preparation phases, OGP motion generated no significant differences; however, continuous rotation developed higher clockwise torque and screw-in force in the 22-mm preparation than in the 20-mm preparation (P < .05). There was no significant difference among the tested groups for transportation values. CONCLUSIONS: Compared with continuous rotation, OGP motion generated less screw-in force, lower clockwise torque, and similar transportation. The #15/0.03 HyFlex EDM instrument and the #13/0.04 prototype MANI instrument performed similarly well.


Assuntos
Parafusos Ósseos , Preparo de Canal Radicular , Instrumentos Odontológicos , Cavidade Pulpar , Desenho de Equipamento , Rotação , Titânio , Torque
5.
Dentomaxillofac Radiol ; 50(1): 20200255, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32706986

RESUMO

OBJECTIVES: To assess quantitatively the combined effect of exomass-related- and motion artefacts on voxel value parameters in cone beam CT (CBCT). METHODS: A cylindrical phantom was manufactured, containing 21 tubes filled with a radiopaque solution, allowing the inclusion of three titanium implants in the periphery to induce exomass-related artefacts. The phantom was mounted on a robot simulating 0.75-, 1.5-, and 3 mm movements (nodding/lateral rotation/tremor). CBCT images with/without exomass and with/without movements were acquired in duplicate in three units: Cranex 3Dx, Orthophos SL-3D, and X1 (with motion-artefact correction). A cylindrical volume of interest was defined in each tube and voxel value mean and standard deviation were assessed. For each CBCT volume, the 21 mean voxel values were averaged providing the overall mean voxel value (MVV), and the standard deviation (among the 21 values) was calculated providing overall voxel value inhomogeneity (VVI). The standard deviation from each of the 21 volumes-of-interest were averaged, providing overall image noise (IN). The effect of the diverse tested situations was inferred from a repeated-measures analysis of variance, followed by Sidak's test (α = 0.05). RESULTS: Overall, images acquired with exomass showed significantly (p ≤ 0.05) lower MVV, and higher VVI and IN. Motion artefacts aggravated exomass-related alterations. MVV and VVI were mostly affected by 3 mm nodding movements. Motion-artefact correction eliminated the deleterious effect of movement. CONCLUSIONS: CBCT voxel-value parameters are altered by exomass-related artefacts, and this finding is aggravated in the presence of motion artefacts. Motion-artefact correction effectively eliminated the deleterious impact of movement.


Assuntos
Artefatos , Tomografia Computadorizada de Feixe Cônico , Movimento , Imagens de Fantasmas , Rotação
6.
Sci Total Environ ; 757: 143786, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33223165

RESUMO

Biogas slurry is widely used as a crop fertilizer due to its available nitrogen content. However, it remains unclear how biogas slurry application affects soil organic carbon (SOC) status and soil microbial community under typical agricultural systems. Here, under a wheat-rice field experiment, we examined the responses of SOC and soil bacterial and fungal communities to biogas slurry application, both with (BSS) and without (BS) straw return, relative to chemical nitrogen fertilizer with (CFS) and without (CF) straw return. The BS treatment significantly increased total organic carbon (TOC) at all soil depths (0-60 cm), compared to CF. Greater TOC occurred at 20-40 cm depth under BSS relative to all other treatments. However, straw return had no impact on soil TOC content under the CF and CFS treatments. Labile organic carbon (LOC) in the topsoil and recalcitrant organic carbon (ROC) at 20-60 cm depth was significantly greater under BS relative to CF. The bacterial class Gammaproteobacteria and family Hyphomicrobiaceae were found to be specifically abundant under biogas slurry application after one year of wheat-rice double cropping. Network analyses showed that the soil bacterial community under biogas slurry application was more complex than under chemical fertilizer application, while the opposite was true for the fungal community. Correlations between network modules and the SOC fractions indicated that biogas slurry application stimulated soil bacteria and fungi to participate in SOC cycling. The module functionality supports our speculation that soil microorganisms degraded the biogas slurry derived-ROC in the topsoil. Overall, we conclude that substitution of chemical fertilizer with biogas slurry can be beneficial for increasing SOC stocks and, in systems with straw return, enhancing straw decomposition.


Assuntos
Microbiota , Oryza , Agricultura , Biocombustíveis , Carbono , Fertilizantes , Rotação , Solo , Triticum
7.
Ying Yong Sheng Tai Xue Bao ; 31(9): 3015-3022, 2020 Sep 15.
Artigo em Chinês | MEDLINE | ID: mdl-33345502

RESUMO

To promote the rational application of nitrogen fertilizer for winter wheat under rice-wheat rotation in the Yangtze River Basin, we examined the effects of nitrogen application rates (0, 120, 210, 300 kg·hm-2, expressed as N0, N1, N2, and N3 respectively) on soil nitrate content, nitrogen balance of soil-plant system and yield. The results showed that soil nitrate content increased with increasing nitrogen application rates. Under different nitrogen application treatments, all the nitrate was significantly transfered to the 60 cm soil layer till jointing stage. After jointing stage, topdressing nitrogen significantly increased nitrate content in 0-40 cm soil layer under N1 and N2 treatments and that in the 0-60 cm soil layer under N3 treatment. Soil nitrate mainly accumulated in the 0-40 cm soil layer in the mature stage. Results from nitrogen balance analysis showed that nitrogen absorption, residue and loss varied across different growth stages of wheat, with the period from overwintering to jointing being the principal time of apparent nitrogen loss. The amount of plant nitrogen accumulation, inorganic nitrogen residue and soil nitrogen apparent loss all positively correlated with the nitrogen application rate. Based on the comprehensive analysis through Coase principle and marginal revenue of environmental economics, the optimum nitrogen application rate for production, ecology and economic benefits of winter wheat under rice-wheat rotation was 250 kg·hm-2, and the ratio of base fertilizer to jointing fertilizer was 5:5, while the corresponding grain yield was 6840 kg·hm-2.


Assuntos
Oryza , Triticum , Agricultura , China , Fertilizantes , Nitrogênio/análise , Rios , Rotação , Solo
9.
Proc Natl Acad Sci U S A ; 117(47): 29647-29657, 2020 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-33168750

RESUMO

The rotation of Paracoccus denitrificans F1-ATPase (PdF1) was studied using single-molecule microscopy. At all concentrations of adenosine triphosphate (ATP) or a slowly hydrolyzable ATP analog (ATPγS), above or below K m, PdF1 showed three dwells per turn, each separated by 120°. Analysis of dwell time between steps showed that PdF1 executes binding, hydrolysis, and probably product release at the same dwell. The comparison of ATP binding and catalytic pauses in single PdF1 molecules suggested that PdF1 executes both elementary events at the same rotary position. This point was confirmed in an inhibition experiment with a nonhydrolyzable ATP analog (AMP-PNP). Rotation assays in the presence of adenosine diphosphate (ADP) or inorganic phosphate at physiological concentrations did not reveal any obvious substeps. Although the possibility of the existence of substeps remains, all of the datasets show that PdF1 is principally a three-stepping motor similar to bacterial vacuolar (V1)-ATPase from Thermus thermophilus This contrasts with all other known F1-ATPases that show six or nine dwells per turn, conducting ATP binding and hydrolysis at different dwells. Pauses by persistent Mg-ADP inhibition or the inhibitory ζ-subunit were also found at the same angular position of the rotation dwell, supporting the simplified chemomechanical scheme of PdF1 Comprehensive analysis of rotary catalysis of F1 from different species, including PdF1, suggests a clear trend in the correlation between the numbers of rotary steps of F1 and Fo domains of F-ATP synthase. F1 motors with more distinctive steps are coupled with proton-conducting Fo rings with fewer proteolipid subunits, giving insight into the design principle the F1Fo of ATP synthase.


Assuntos
Mitocôndrias/metabolismo , Paracoccus denitrificans/metabolismo , ATPases Translocadoras de Prótons/metabolismo , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Hidrólise , Cinética , Rotação , Thermus thermophilus/metabolismo
10.
Am J Sports Med ; 48(14): 3495-3502, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33176107

RESUMO

BACKGROUND: The pivot-shift test is used to assess for rotatory knee laxity in the anterior cruciate ligament (ACL)-deficient knee and ACL-reconstructed knee; however, the pivot shift uses a subjective grading system that is limited by variability between examiners. Consequently, quantified pivot shift (QPS) test software (PIVOT iPad application) has been developed and validated to measure the magnitude of rotatory knee laxity during the positive pivot-shift test. PURPOSE: To employ intraoperative QPS (iQPS) to assess for differences in residual rotatory knee laxity after ACL reconstruction (ACLR) versus ACLR augmented with lateral extra-articular tenodesis (ACLR + LET), and to employ iQPS to determine if ACLR and/or ACLR + LET result in overconstrained knee kinematics when compared with the contralateral knee. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: iQPS was performed in 20 patients by a single surgeon on both the operative and contralateral knees before ACLR. ACLR was augmented with a LET if the lateral compartment tibial translation measured during QPS was greater than or equal to double the amount of lateral tibial compartment translation measured for the contralateral knee. After each reconstruction (ACLR or ACLR + LET), iQPS measurements were performed. iQPS data were compared with the preoperative QPS measurements of the operative and contralateral knees. Postoperative iQPS data were compared with both the preoperative QPS measurements of the operative and contralateral knees with paired samples t tests. Categorical variables were compared using the Fisher exact test. RESULTS: The mean age in the cohort was 17.3 years (range, 15-24 years). There were no significant differences between the groups in terms of the proportion of male patients (ACLR: 5 male, 5 female vs ACLR + LET: 4 male, 6 female) or age (ACLR: 17.7 ± 3.3 years; 95% CI, 15.4-24.0 vs ACLR + LET: 16.8 ± 2.8 years, 95% CI, 14.8-22.0; P = .999). There were no significant differences between the groups with respect to preoperative QPS performed during examination under anesthesia (ACLR: 4.7 ± 2.0 mm; 95% CI, 3.3-6.1 vs ACLR + LET: 3.6 ± 1.8 mm; 95% CI, 2.3-4.9; P = .2). Both ACLR and ACLR + LET resulted in significant decreases in rotatory knee laxity when compared with preoperative QPS measurements (ACLR: -3.4 ± 1.7 mm; 95% CI, -4.6 to -2.2; P < .001: ACLR + LET: -2.6 ± 1.9 mm; 95% CI, -3.9 to -1.3; P < .002). Moreover, when compared with isolated ACLR, ACLR + LET did not result in a significantly smaller magnitude of change in iQPS between the pre- and postoperative states (P = .3). CONCLUSION: Both ACLR and ACLR + LET resulted in significant decreases in rotatory knee laxity. The augmentation of ACLR with LET did not change the constraint of the knee with respect to lateral compartment translation as measured during iQPS.


Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior , Instabilidade Articular , Tenodese , Adolescente , Adulto , Lesões do Ligamento Cruzado Anterior/cirurgia , Fenômenos Biomecânicos , Estudos de Coortes , Feminino , Humanos , Instabilidade Articular/cirurgia , Articulação do Joelho/cirurgia , Masculino , Amplitude de Movimento Articular , Rotação , Software , Cirurgia Assistida por Computador , Adulto Jovem
11.
Sci Rep ; 10(1): 19979, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33203930

RESUMO

Some studies have reported that upper limb tightness is a risk factor for shoulder/elbow pain in high school baseball pitchers; but there has been insufficient research on the relationship between lower limb tightness and shoulder and elbow pain in pitchers. This study aimed to clarify the correlation among pre-season hip range of motion (ROM) and shoulder and elbow disorders in high school baseball pitchers. We surveyed 125 high school pitchers. Hip ROM was measured in the supine and prone positions. After the season, based on their answers to the self-recorded questionnaire, a "shoulder or elbow injury" was defined as any condition resulting in the pitcher being considered disabled for ≥ 8 days. An independent t-test and logistic regression analysis were used for statistical analysis. Eleven disabled pitchers (9%) were identified during the season. In the injured group, the ROM of the plant side hip with 90° flexed external rotation was smaller than that in the non-injured group. Preseason limited ROM in the plant side hip with 90° flexed external rotation was a risk factor for the occurrence of shoulder/elbow pain in the season.


Assuntos
Beisebol/fisiologia , Articulação do Cotovelo/fisiologia , Cotovelo/fisiopatologia , Articulação do Quadril/fisiopatologia , Lesões do Ombro/etiologia , Articulação do Ombro/fisiologia , Ombro/fisiopatologia , Criança , Feminino , Humanos , Extremidade Inferior/fisiopatologia , Masculino , Estudos Prospectivos , Amplitude de Movimento Articular , Fatores de Risco , Rotação , Instituições Acadêmicas
12.
Bone Joint J ; 102-B(11): 1438-1445, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33135432

RESUMO

AIMS: Scapular notching is thought to have an adverse effect on the outcome of reverse total shoulder arthroplasty (RTSA). However, the matter is still controversial. The aim of this study was to determine the clinical impact of scapular notching on outcomes after RTSA. METHODS: Three electronic databases (PubMed, Cochrane Database, and EMBASE) were searched for studies which evaluated the influence of scapular notching on clinical outcome after RTSA. The quality of each study was assessed. Functional outcome scores (the Constant-Murley scores (CMS), and the American Shoulder and Elbow Surgeons (ASES) scores), and postoperative range of movement (forward flexion (FF), abduction, and external rotation (ER)) were extracted and subjected to meta-analysis. Effect sizes were expressed as weighted mean differences (WMD). RESULTS: In all, 11 studies (two level III and nine level IV) were included in the meta-analysis. All analyzed variables indicated that scapular notching has a negative effect on the outcome of RTSA . Statistical significance was found for the CMS (WMD -3.11; 95% confidence interval (CI) -4.98 to -1.23), the ASES score (WMD -6.50; 95% CI -10.80 to -2.19), FF (WMD -6.3°; 95% CI -9.9° to -2.6°), and abduction (WMD -9.4°; 95% CI -17.8° to -1.0°), but not for ER (WMD -0.6°; 95% CI -3.7° to 2.5°). CONCLUSION: The current literature suggests that patients with scapular notching after RTSA have significantly worse results when evaluated by the CMS, ASES score, and range of movement in flexion and abduction. Cite this article: Bone Joint J 2020;102-B(11):1438-1445.


Assuntos
Artroplastia do Ombro/efeitos adversos , Doenças Ósseas/etiologia , Artropatias/cirurgia , Escápula/lesões , Articulação do Ombro/cirurgia , Artroplastia do Ombro/métodos , Humanos , Amplitude de Movimento Articular , Rotação , Resultado do Tratamento
13.
Huan Jing Ke Xue ; 41(11): 5168-5175, 2020 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124261

RESUMO

In this study, a continuous rape-rice rotation plot experiment was conducted over three years. Repair materials were continuously applied in the first two years, and no repair materials were applied in the second year. The repair effects of hydroxyapatite, lime, biochar, bio-organic fertilizer, and nano-materials on copper contaminated soil and the enrichment of copper in different parts of rape and rice were investigated. The results show that hydroxyapatite, lime, and nanomaterials can significantly increase soil pH, and different restoration materials can effectively inhibit the movement of soil copper. The effective copper treatment with lime restoration soil had the largest decrease. The four seasons of continuous application of restoration materials were 38.9%, 34.9%, 27.88%, and 29.04%, respectively, and the subsequent effect of lime passivation of effective copper was better than other restoration materials. The application of the repair material significantly reduced the copper content in edible parts of rape and rice. In the four seasons of application of the repair material, the maximum copper content in edible parts of different crops decreased by 46.03%, 22.2%, 29.44%, and 31.71%, respectively. Due to the application effect of the repair material, the copper content in the edible part of the two season crops, without the repair material, did not exceed the national food safety limit. With the use of different repair materials, the yields of rapeseed and rice were improved. This test can provide some theoretical basis and technical support for soil improvement in copper-contaminated areas.


Assuntos
Recuperação e Remediação Ambiental , Oryza , Poluentes do Solo , Cádmio/análise , Carvão Vegetal , Cobre , Rotação , Solo , Poluentes do Solo/análise
14.
Huan Jing Ke Xue ; 41(10): 4701-4710, 2020 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124403

RESUMO

A field experiment was carried out to investigate the effects of different rice-rape rotation systems on methane and nitrous oxide emissions, which were measured using the static chamber/gas chromatography method, prediction of their global warming potentials (GWP), and greenhouse gas intensity (GHGI) in paddy fields. The results showed that the average cumulative emissions of CH4from a double cropping paddy field, single season rice field (including middle or late), rape field, and leisure land were 135.25, 55.64, 5.05, and 1.89 kg ·hm-2, respectively. The CH4 emission during the rice season accounted for 91.8%-98.5% of the annual CH4 emission in different rotation years, and the contents of dissolved organic carbon in paddy soil exhibited a significantly positive correlation with CH4 emission. The CH4 emission in conventional late rice paddy was 18.7% higher than that of hybrid late rice paddy (P<0.05). The average cumulative emissions of N2O from double cropping paddy field, single season rice field (including middle or late), rape field, and leisure land were 0.94, 0.64, 1.38, and 0.24 kg ·hm-2, respectively. Out of the total annual N2O emission, 57.2% to 70.2% was from the rape field; 17.8% and 30.6% was due to the winter fallow treatments with previous crop type of double corpping rice and single season rice, respectively. There was no significant difference in N2O emission between hybrid rice and conventional rice paddy fields. The GWP of double cropping rice-winter fallow and double cropping rice-rape was higher than that of rice-rape and rice-winter fallow, and the GWP of CH4 in rice season accounted for 71.2% to 90.9% of the annual GWP of rotation. The highest treatment of GHGI was rice-rice-rape, and the treatment of rice-oil and rice-winter slack was lower. According to the comprehensive environmental and economic benefits, the late hybrid rice-rape patterns should be selected to reduce greenhouse gases in multiple cropping rice fields of South China.


Assuntos
Óxido Nitroso , Oryza , Agricultura , China , Aquecimento Global , Metano/análise , Óxido Nitroso/análise , Rotação , Solo
15.
PLoS One ; 15(10): e0238785, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33052931

RESUMO

A human cadaveric specimen-specific knee model with appropriate soft tissue constraints was developed to appropriately simulate the biomechanical environment in the human knee, in order to pre-clinically evaluate the biomechanical and tribological performance of soft tissue interventions. Four human cadaveric knees were studied in a natural knee simulator under force control conditions in the anterior posterior (AP) and tibial rotation (TR) axes, using virtual springs to replicate the function of soft tissues. The most appropriate spring constraints for each knee were determined by comparing the kinematic outputs in terms of AP displacement and TR angle of the human knee with all the soft tissues intact, to the same knee with all the soft tissues resected and replaced with virtual spring constraints (spring rate and free length/degree). The virtual spring conditions that showed the least difference in the AP displacement and TR angle outputs compared to the intact knee were considered to be the most appropriate spring conditions for each knee. The resulting AP displacement and TR angle profiles under the appropriate virtual spring conditions all showed similar shapes to the individual intact knee for each donor. This indicated that the application of the combination of virtual AP and TR springs with appropriate free lengths/degrees was successful in simulating the natural human knee soft tissue function. Each human knee joint had different kinematics as a result of variations in anatomy and soft tissue laxity. The most appropriate AP spring rate for the four human knees varied from 20 to 55 N/mm and the TR spring rate varied from 0.3 to 1.0 Nm/°. Consequently, the most appropriate spring condition for each knee was unique and required specific combinations of spring rate and free length/degree in each of the two axes.


Assuntos
Joelho/fisiologia , Modelos Biológicos , Idoso , Fenômenos Biomecânicos , Cadáver , Simulação por Computador , Tecido Conjuntivo/anatomia & histologia , Tecido Conjuntivo/fisiologia , Feminino , Humanos , Joelho/anatomia & histologia , Articulação do Joelho/anatomia & histologia , Articulação do Joelho/fisiologia , Masculino , Pessoa de Meia-Idade , Amplitude de Movimento Articular , Rotação , Tíbia/anatomia & histologia , Tíbia/fisiologia , Torque
16.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(9): 1104-1108, 2020.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-33051425

RESUMO

OBJECTIVES: To study the effect of rotation errors on the γ pass rate of volume-modulated arc therapy (VMAT) plan in rectal cancer based on the ArcCheck phantom. METHODS: CT data from 20 rectal cancer patients underwent VMRT were selected randomly for this study. Targeting areas were selected, and clinical radiotherapy and validation plans were formulated. ArcCheck model was selected to validate the radiotherapy plans. The effect of the rotation errors on the dosimetric verification for VMAT in rectal cancer was simulated and analyzed with ArcCheck model software. RESULTS: When there was no rotation errors, the γ pass rate of VMRT plans was more than 95%. When the absolute rotation angle was less than or equal to 1°, the γ pass rate of VMAT plans was more than 90%, meeting the clinical requirements. When the absolute rotation angle was greater than 1°, the γ pass rate was less than 90%, which did not meet clinical requirements. CONCLUSIONS: The rotation errors affect the γ pass rate of VMAT plans. The larger the rotation angle, the lower the γ pass rate. It meets clinical requirements when the rotation error is less than or equal to 1°.


Assuntos
Radioterapia de Intensidade Modulada , Neoplasias Retais , Humanos , Radiometria , Planejamento da Radioterapia Assistida por Computador , Neoplasias Retais/radioterapia , Rotação
17.
Am J Sports Med ; 48(13): 3183-3193, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33017168

RESUMO

BACKGROUND: The biomechanical effect of lateral extra-articular tenodesis (LET) performed in conjunction with anterior cruciate ligament (ACL) reconstruction (ACLR) on load sharing between the ACL graft and the LET and on knee kinematics is not clear. PURPOSE/HYPOTHESIS: The purpose was to quantify the effect of LET on (1) forces carried by both the ACL graft and the LET and (2) tibiofemoral kinematics in response to simulated pivot shift and anterior laxity tests. We hypothesized that LET would decrease forces carried by the ACL graft and anterior tibial translation (ATT) in response to simulated pivoting maneuvers and during simulated tests of anterior laxity. STUDY DESIGN: Controlled laboratory study. METHODS: Seven cadaveric knees (mean age, 39 ± 12 years [range, 28-54 years]; 4 male) were mounted to a robotic manipulator. The robot simulated clinical pivoting maneuvers and tests of anterior laxity: namely, the Lachman and anterior drawer tests. Each knee was assessed in the following states: ACL intact, ACL sectioned, ACL reconstructed (using a bone-patellar tendon-bone autograft), and after performing LET (the modified Lemaire technique after sectioning of the anterolateral ligament and Kaplan fibers). Resultant forces carried by the ACL graft and LET at the peak applied loads were determined via superposition. ATT was determined in response to the applied loads. RESULTS: With the applied pivoting loads, performing LET decreased ACL graft force up to 80% (44 ± 12 N; P < .001) and decreased ATT of the lateral compartment compared with that of the intact knee up to 7.6 ± 2.9 mm (P < .001). The LET carried up to 91% of the force generated in the ACL graft during isolated ACLR (without LET). For simulated tests of anterior laxity, performing LET decreased ACL graft force by 70% (40 ± 20 N; P = .001) for the anterior drawer test with no significant difference detected for the Lachman test. No differences in ATT were deteced between ACLR with LET and the intact knee on both the Lachman and the anterior drawer tests (P = .409). LET reduced ATT compared with isolated ACLR on the simulated anterior drawer test by 2.4 ± 1.8 mm (P = .032) but not on the simulated Lachman test. CONCLUSION: In a cadaveric model, LET in combination with ACLR transferred loads from the ACL graft to the LET and reduced ATT with applied pivoting loads and during the simulated anterior drawer test. The effect of LET on ACL graft force and ATT was less pronounced on the simulated Lachman test. CLINICAL RELEVANCE: LET in addition to ACLR may be a suitable option to offload the ACL graft and to reduce ATT in the lateral compartment to magnitudes less than that of the intact knee with clinical pivoting maneuvers. In contrast, LET did not offload the ACL graft or add to the anterior restraint provided by the ACL graft during the Lachman test.


Assuntos
Lesões do Ligamento Cruzado Anterior , Instabilidade Articular , Tenodese , Adulto , Ligamento Cruzado Anterior/cirurgia , Lesões do Ligamento Cruzado Anterior/cirurgia , Fenômenos Biomecânicos , Cadáver , Feminino , Humanos , Instabilidade Articular/prevenção & controle , Instabilidade Articular/cirurgia , Articulação do Joelho/cirurgia , Masculino , Pessoa de Meia-Idade , Amplitude de Movimento Articular , Rotação
20.
Klin Monbl Augenheilkd ; 237(10): 1172-1176, 2020 Oct.
Artigo em Inglês, Alemão | MEDLINE | ID: mdl-33059376

RESUMO

The digital media becomes more and more common in our everyday lives. So it is not surprising that technical progress is also leaving its mark on amblyopia therapy. New media and technologies can be used both in the actual amblyopia therapy or therapy monitoring. In particular in this review shutter glasses, therapy monitoring and analysis using microsensors and newer video programs for amblyopia therapy are presented and critically discussed. Currently, these cannot yet replace classic amblyopia therapy. They represent interesting options that will occupy us even more in the future.


Assuntos
Ambliopia , Ambliopia/diagnóstico , Ambliopia/terapia , Óculos , Humanos , Internet , Rotação , Privação Sensorial
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