Can oblique lateral interbody fusion (OLIF) create more lumbosacral lordosis in lumbar spine surgery than minimally invasive transforaminal interbody fusion (MIS-TLIF)?

ObjectiveTo compare the differences in the correction effect for lumbosacral lordosis and clinical outcomes between OLIF with/without posterior pedicle screw fixation (PSF) and MIS-TLIF through a retrospective cohort study.MethodThere were 98 consecutive patients originally enrolled for the study, but 15 patients were excluded due to intraoperative endplate injury or osteotomy performed for severe spinal deformity. Thus, 83 patients included in this study (36 males and 47 females, mean age 65.8 years) underwent single to three-segment OLIF (including OLIF + PSF and OLIF Standalone) or MIS-TLIF surgery from 2016 to 2018. The operation time, bleeding and blood transfusion, fusion rate, complication, pre-and postoperative visual analogue scale (VAS), Oswestry Disability Index (ODI) were evaluated. In addition, radiological parameters including lumbosacral lordosis (LL), fused segment lordosis (FSL), anterior disc height (ADH) and posterior disc height (PDH) were measured. The clinical outcomes, LL, FSL, ADH and PDH restored and were compared between the OLIF group, OLIF subgroups and MIS-TLIF group.ResultsThe average operation time and intraoperative bleeding were significantly less in the OLIF group than in the MIS-TLIF group (163 ± 68 vs. 233 ± 79 min, 116 ± 148 vs. 434 ± 201 ml, P < 0.001). There was no statistically significant difference between the OLIF group and the MIS-TLIF group in VAS and ODI improvements, fusion rate, complication, LL and FSL correction (P > 0.05). The ADH and PDH increases in the OLIF group were more than that in MIS-TLIF group (P < 0.001). The correction of LL was significantly more in the OLIF + PSF group than in the MIS-TLIF group (9.9 ± 11.1 vs. 4.2 ± 6.1deg, P = 0.034).ConclusionOLIF and MIS-TLIF are both safe and effective procedures, capable of restoring lumbosacral lordosis and disc height partly. Combined with PSF, OLIF can achieve a better correction effect of lumbosacral lordosis than MIS-TLIF

Individual effect of recrystallisation nucleation sites on texture weakening in a magnesium alloy: Part 1- double twins

Recrystallised grain nucleation, grain growth and corresponding texture evolution in a cold-rolled rare earth containing WE43 Mg alloy during annealing at 490 �C was fully tracked using a quasi-in-situ electron backscatter diffraction method. The results show nucleation sites, such as double twins, can weaken the deformed texture and for the first time provide direct evidence that recrystallised grains originating from double twins can form the rare earth texture during annealing. Precipitation and recrystallisation occurred concurrently during most of the annealing period, with precipitates forming preferentially along prior grain and twin boundaries. These precipitates effectively retard the recrystallisation due to particle pinning leading to an excessively long time for the completion of recrystallisation. A large portion of recrystallised grains were observed to have 〈0001〉 poles tilted 20e45� away from the normal direction. The RE texture emerges during the nucleation of recrystallised grains and is maintained during subsequent uniform grain growth, which results in a stable RE texture being developed as recrystallisation progresses. The uniform grain growth could be attributed to solute drag suppressing the grain boundary mobility of those grains that had recrystallised with a basal texture and precipitate pinning restricting potential orientated grain growth

Recherche du boson de Higgs du mod`ele standard dans l’etat final WH → ℓνb¯b avec 9.7 fb−1 de collisions p¯p dans l’experience DØ.

Searches for the Higgs boson have started as soon as the underlying model for particle mass generation has been proposed, and the search went on for several decades at LEP, Tevatron and LHC. Last year the ATLAS and CMS Collaborations at the Large Hadron Collider (LHC) have reported the observation of a new boson [1, 2]. At the same time the CDF and D0 Collaborations reported combined evidence for a particle, with a mass consistent with that of the new boson observed at LHC [3].This thesis presents the search by the D0 collaboration for the SM Higgs boson using events containing one isolated charged lepton (ℓ = e or μ), a significant imbalance in transverse energy (6ET ), and two or more jets, which is part of the Tevatron Higgs combination.Les recherches pour le boson de Higgs ont commencé dès que le modèle sous-jacent pour la génération de masse de particules a été proposé et la recherche a continué pendant plusieurs décennies au LEP, au Tevatron et au LHC. L'an dernier, les Collaborations ATLAS et CMS au Large Hadron Collider (LHC) ont rapporté l'observation d'un nouveau boson [1, 2]. Dans le même temps, la CDF et D0 Collaborations ont rapporté des preuves combinées pour une particule, avec une masse compatible avec celle du nouveau boson observé au LHC [3].Cette thèse présente la recherche par la collaboration D0 pour le boson de Higgs de SM en utilisant des événements contenant un lepton chargé isolé (ℓ = e ou μ), un déséquilibre significatif en énergie transversale (6ET) et deux jets ou plus, qui fait partie de la Tevatron Higgs combinaison

Decoupling control law for structural control implementation

Multi-story buildings, subjected to wind or earthquake excitation, can be modeled as multi-degree of freedom (MDOF) systems defined by a set of coupled second order ordinary differential equations. In this paper, the dynamic coupling characteristics of multi-story building are examined, and it is found that the coupled property in a system can be described as a positive feedback from the control theory point of view. This positive feedback property of a MDOF system may intensify structural vibration. For the structural control implementation, open-loop and closed-loop decoupling control laws are proposed. All coupled “channels” of the system are “broken off” when the vibration control design is based on the proposed control laws. A complex MDOF structural system, therefore, is equivalent to a set of single degree of freedom (SDOF) systems, and the control design can be carried out independently for any specific degree of freedom. Thus, the proposed control laws provide an efficient tool by which the vibration of a selected floor can be suppressed without any effect on its neighboring floors because the control is one to one. Meanwhile, the computational procedure of the control design can be significantly simplified because all analyses and design are conducted based on SDOF systems

The role of prevertebral soft tissue swelling in dysphagia after anterior cervical corpectomy fusion: change trends and risk factors

Abstract Objectives This study aimed to analyze the change trends of prevertebral soft tissue swelling (PSTS) for anterior cervical corpectomy fusion(ACCF) and to evaluate the risk factors of PSTS for postoperative dysphagia. Methods There were 309 patients with degenerative cervical diseases who were treated with ACCF from November 2015 and September 2019 in our hospital. According to the symptom of swallowing function after ACCF, those were divided into the dysphagia group and the normal-swallowing function group. Cervical computed tomography(CT) was analyzed, and radiological evaluation of the prevertebral soft tissue was measured between the antero-inferior corner of each vertebral body and the air shadow of the airway through CT mid-sagittal slice images before operation and after operation(one week, one month, eight months and twelve months). Results The incidence of dysphagia after ACCF was 41.1%. 120 of 127(94.5%) patients had dysphagia disappeared at the 8 months after ACCF, and all disappeared at the 12 months. In both groups, PSTS would be biggest at 1 week postoperatively comparing to the preoperative, and then get smaller from 1 week to 12 months postoperatively (p < 0.05). After 12 months of operation, the PSTS of all cervical spinal levels would get equal to the preoperative size in the normal-swallowing function group, while the PSTS in dysphagia group would get equal only in C5-7 levels. The PSTS of preoperative C6 level and postoperative C2 level were more closely related to the present of postoperative dysphagia (OR: 9.403, 95%CI: 2.344–37.719, OR: 3.187, 95%CI: 1.78-5.705). It was more important to predict postoperative dysphagia using the value of PSTS at preoperative C6 level and postoperative C2 level, with the cutoff threshold for the PSTS of preoperative C6 level ≦1.51 cm and postoperative C2 level ≦1.3915 cm, which could get sensitivity & specificity 66.929% and 61.54%, 77.17% and 64.29%, respectively. Conclusion Our study showed that the increasing of the PSTS after ACCF should be considered as a risk factor of dysphagia after surgery. With the recovery of PSTS over time, the incidence of postoperative dysphagia decreases. The PSTS of preoperative C6 level and and postoperative C2 level should play an important part in predicting the risk of postoperative dysphagia

Nondestructive Measurement of Emissivity of Damaged Parts of Coatings

Low Infrared emissivity coating (LIREC) is prone to generating some problems such as bulges, degumming, and abrasion. In order to study whether the performance of LIREC under different damages can meet the work needs, it is essential to timely measure and evaluate the performance state of LIREC in the application process. The existing methods for measuring the damage of LIREC have some disadvantages such as expensive equipment, complex operation, and inaccurate measurement results. In this paper, a measurement method of LIREC damage capability based on thermal imager is proposed. The radiation temperature is measured by thermal imager, the real temperature and ambient temperature of coating surface are measured by thermocouple, and the emittance of coating surface is calculated. Non-contact and continuous large-area emissivity measurements are carried out on the damaged parts of the coating and verified by experiments. The measurement results show that the different damage types and damage degrees directly affect the measurement results of LIREC. Wear damage increases the emissivity of the coating while debonding damage basically does not change the coating emissivity. Shedding damage of small diameter forms voids, which causes the increase of the damage parts of emittance. In addition, bulge damage impedes temperature transfer and reduces emissivity. This method can timely and accurately measure and evaluate the performance state of LIREC and can provide a new idea for the accurate measurement of damage emissivity of LIREC

Centrality dependence of light (anti)nuclei and (anti)hypertriton production in Pb-Pb collisions at

The centrality dependence of light (anti)nuclei and (anti)hypertriton production in Pb-Pb collisions at $\sqrt{s_{NN}} = 2.76$ TeV are investigated using the dynamically constrained phase-space coalescence (DCPC) model and the parton and hadron cascade (PACIAE) model. We found that the yields of light (anti)nuclei and (anti)hypertriton strongly depend on the centrality, i.e., their yields decrease rapidly with the increase of centrality; but their yield ratios are independent of centrality. The results from our theoretical model are well consistent with ALICE data. Furthermore, we found that the integrated yields of (anti)nuclei per participant nucleon increase from peripheral to central collisions, and a higher mass number corresponds to a more rapid increase of such yields. The coalescence parameters $B_{A}$ of light (anti)nuclei and (anti)hypernuclei are also analyzed

Manipulating the mechanical strength and thermal conductivity of a Mg–4Zn-0.6Zr alloy through Ca addition

In this study, the microstructure, mechanical properties, and thermal conductivity of as-extruded Mg–4Zn-0.6Zr-xCa (x = 0, 0.3, 0.6, 0.9 wt%) alloys were investigated. The results revealed a bimodal grain size distribution in all the alloys due to incomplete dynamic recrystallization (DRX), characterized by the coexistence of elongated deformed grains and equiaxed DRX grains. The bimodal grain size distribution enhanced the mechanical properties of the studied alloys. Furthermore, Ca alloying facilitated the formation of Ca2Mg6Zn3 phases, through which the DRX extent was also enhanced. The precipitation of secondary phases, along with the increased DRX induced by Ca addition, was beneficial in eliminating the lattice distortion of the alloys, resulting in improved thermal conductivity compared to the Ca-free Mg–4Zn-0.6Zr alloy. The optimum combination of mechanical properties and thermal conductivity was achieved in the Mg–4Zn-0.6Zr-0.6Ca alloy, with yielding strength, ultimate tensile strength, tensile fracture elongation, and thermal conductivity values of 271 MPa, 318 MPa, 17.6 %, and 123.9 W/(m‧K), respectively. This work demonstrates that Mg–Zn–Zr–Ca-based alloys can be developed with high strength and high thermal conductivity, significantly expanding the industrial application of magnesium alloys

Effects of micro-alloying Ag on microstructure, mechanical properties and corrosion behavior of extruded Mg-2Zn-0.2Ca-xAg alloys

The present work investigates effects of micro-alloying Ag on the microstructure, mechanical properties and corrosion behavior of as-extruded Mg-2Zn-0.2Ca alloys. The addition of Ag, up to 0.5 wt.%, induce limited difference on microstructural characteristics such as slightly coarser microstructures due to the enhanced dynamic recrystallization process and the presence of refined precipitates. The tensile properties of the alloy were not significantly changed by Ag addition, i.e., all the alloys exhibited exceptional elongation of ~30%, moderate tensile yield strength and ultimate strength of ~140 MPa and ~240 MPa, respectively. The corrosion performance of the alloys was progressively deteriorated with increasing Ag content i.e., the corrosion rate increased from 0.40 ± 0.23 mm/y for Mg-2Zn-0.2Ca alloy to 3.27 ± 0.24 mm/y for the Mg-2Zn-0.2Ca-0.5Ag alloy. The compromised corrosion performance was attributed to a large electrode potential difference between the nobler Ca2Mg6Zn3 phase and the α-Mg matrix as well as a less protective corrosion film, by increasing Ag addition

The complete mitochondrial genome of a new geographical population of freshwater fish <i>Macropodus hongkongensis</i> (Freyhof & Herder, 2002)

Macropodus hongkongensis (Freyhof & Herder, 2002), is sparsely distributed in Hong Kong and Guangdong provinces. Recently, a new geographical population of M. hongkongensis was discovered in the Wanquan River in the Hainan province. Therefore, this study focused on sequencing the complete mitochondrial genome of the new geographical population of Macropodus hongkongensis from the Wanquan River. The circular mtDNA molecule was 16,492 bp in size, and the overall base compositions were A (30.30%), C (24.90%), T (29.80%), and G (15.00%), with a slight bias toward A + T. The complete mitogenome encoded 13 protein-coding genes (PCGs), 22 tRNA genes, 2 rRNA genes, and a control region. Phylogenetic analysis indicated that M. hongkongensis of the Hainan Wanquan River was most closely related to the M. hongkongensis of the Gongdong population. These results provide useful genetic information for species identification and phylogenetic studies of Macropodus species.</p