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Hydromassage of macular hole edges for large and persistent full-thickness macular holes
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作者 Yi Cai Wen-Bo Liu +5 位作者 Duo Wei Xun Deng Xiao-Xin Li Ming-Wei Zhao Xuan Shi Jian-Hong Liang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第3期551-557,共7页
●AIM:To introduce the macular hole(MH)hydromassage technique as a potentially beneficial approach for the treatment of large or persistent MH.●METHODS:This retrospective observational case series comprised 16 consec... ●AIM:To introduce the macular hole(MH)hydromassage technique as a potentially beneficial approach for the treatment of large or persistent MH.●METHODS:This retrospective observational case series comprised 16 consecutive patients(17 eyes)diagnosed with MH.Inclusion criteria involved a hole aperture diameter larger than 600μm or the presence of an unclosed MH larger than 600μm following the previous vitrectomy.Standard MH repair procedures were administered in all cases,involving the manipulation and aspiration of the hole margin through the application of water flow with a soft-tip flute needle.A comprehensive assessment was conducted for each case before and after surgery,and optical coherence tomography(OCT)images were captured at every follow-up point.●RESULTS:The mean preoperative aperture diameter was 747±156μm(range 611-1180μm),with a mean base diameter of 1390±435μm(range 578-2220μm).Following surgery,all cases achieved complete anatomical closure of MH,with 13 cases(76.5%)exhibiting type 1 closure and 4 cases(23.5%)demonstrating type 2 closure.No significant differences were observed in the preoperative OCT variables between the two closure types.Eyes with type 1 closure showed a significantly improved visual acuity(0.70±0.10,range 0.50-0.80)compared to those with type 2 closure(0.90±0.12,range 0.80-1.00,P=0.014).●CONCLUSION:The MH hydromassage technique demonstrates promising results,achieving acceptable closure rates in cases of large or persistent MH.This technique may serve as an effective adjunctive maneuver during challenging MH surgery. 展开更多
关键词 macular hole large macular hole persistent macular hole optical coherence tomography surgical technique hydromassage
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Statistical study of magnetic holes in the upstream region of Mercury’s bow shock
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作者 GuoQiang Wang SuDong Xiao +2 位作者 MingYu Wu YuanQiang Chen TieLong Zhang 《Earth and Planetary Physics》 EI CAS CSCD 2024年第2期326-337,共12页
Magnetic holes are magnetic depression structures that exist widely in many plasma environments.The magnetic holes with durations of>1 s in the solar wind at Mercury’s orbit have drawn much attention,but the prope... Magnetic holes are magnetic depression structures that exist widely in many plasma environments.The magnetic holes with durations of>1 s in the solar wind at Mercury’s orbit have drawn much attention,but the properties of the magnetic holes with shorter durations are still unclear.Here,we investigate the magnetic holes with durations of 0.1-100 s in the upstream region of Mercury’s bow shock based on observations by the MESSENGER(MErcury Surface,Space ENvironment,GEochemistry,and Ranging)spacecraft.They can be divided into two groups according to the distribution of their duration:small-duration magnetic holes(SDMHs,<0.6 s)and large-duration magnetic holes(LDMHs,>0.6 s).The duration of each group approximately obeys a log-normal distribution with a median of~0.25 s and 3 s,respectively.Approximately 1.7%(32.6%)of the SDMHs(LDMHs)reduce the magnetic field strength by more than 50%.For both groups,some structures have a linear or quasi-linear polarization,whereas others have an elliptical polarization.The magnetic hole events in both groups tend to have a higher rate of occurrence when the interplanetary magnetic field strength is weaker.Their occurrence rates are also affected by Mercury’s foreshock,which can increase(decrease)the occurrence rate of the SDMHs(LDMHs).This finding suggests that Mercury’s foreshock might be one source of the SDMHs and that the foreshock can destroy some LDMHs.These observations suggest that a new group of magnetic holes with durations of<0.6 s exist in the upstream region of Mercury’s bow shock. 展开更多
关键词 magnetic hole solar wind MERCURY FORESHOCK
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View of thermodynamic phase transition of the charged Gauss-Bonnet AdS black hole via the shadow
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作者 何柯腱 郭森 +1 位作者 罗智 李国平 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期355-362,共8页
We examine thermodynamic phase transition(PT)of the charged Gauss-Bonnet Ad S black hole(BH)by utilizing the shadow radius.In this system,we rescale the corresponding Gauss-Bonnet coefficientαby a factor of 1/(D-4),a... We examine thermodynamic phase transition(PT)of the charged Gauss-Bonnet Ad S black hole(BH)by utilizing the shadow radius.In this system,we rescale the corresponding Gauss-Bonnet coefficientαby a factor of 1/(D-4),and ensure thatαis positive to avoid any singularity problems.The equation derived for the shadow radius indicates that it increases as the event horizon radius increases,making it an independent variable for determining BH temperature.By investigating the PT curve in relation to shadows,we can observe that the shadow radius can be used as an alternative to the event horizon radius in explaining the phenomenon of BH PT.Furthermore,the results indicate that an increase in the parameterαcorresponds to a decrease in the temperature of the BH.By utilizing the relationship between the temperature and the shadow radius,it is possible to obtain the thermal profile of the Gauss-Bonnet AdS BH.It is evident that there is an N-type variation in temperature for pressures P<P_(c).Additionally,as the parameterαincreases,the region covered by shadow expands while the temperature decreases.The utilization of BH shadows as a probe holds immense significance in gaining a deeper understanding of BH thermodynamic behavior. 展开更多
关键词 Gauss-Bonnet AdS black hole thermodynamic SHADOW
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Triple points and phase transitions of D-dimensional dyonic Ad S black holes with quasitopological electromagnetism in Einstein–Gauss–Bonnet gravity
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作者 牟平辉 蒋青权 +1 位作者 何柯腱 李国平 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期272-287,共16页
By considering the negative cosmological constant Λ as a thermodynamic pressure, we study the thermodynamics and phase transitions of the D-dimensional dyonic Ad S black holes(BHs) with quasitopological electromagnet... By considering the negative cosmological constant Λ as a thermodynamic pressure, we study the thermodynamics and phase transitions of the D-dimensional dyonic Ad S black holes(BHs) with quasitopological electromagnetism in Einstein–Gauss–Bonnet(EGB) gravity. The results indicate that the small/large BH phase transition that is similar to the van der Waals(vdW) liquid/gas phase transition always exists for any spacetime dimensions. Interestingly, we then find that this BH system exhibits a more complex phase structure in 6-dimensional case that is missed in other dimensions.Specifically, it shows for D = 6 that we observed the small/intermediate/large BH phase transitions in a specific parameter region with the triple point naturally appeared. Moreover, when the magnetic charge turned off, we still observed the small/intermediate/large BH phase transitions and triple point only in 6-dimensional spacetime, which is consistent with the previous results. However, for the dyonic Ad S BHs with quasitopological electromagnetism in Einstein–Born–Infeld(EBI) gravity, the novel phase structure composed of two separate coexistence curves observed by Li et al. [Phys. Rev. D105 104048(2022)] disappeared in EGB gravity. This implies that this novel phase structure is closely related to gravity theories, and seems to have nothing to do with the effect of quasitopological electromagnetism. In addition, it is also true that the critical exponents calculated near the critical points possess identical values as mean field theory. Finally, we conclude that these findings shall provide some deep insights into the intriguing thermodynamic properties of the dyonic Ad S BHs with quasitopological electromagnetism in EGB gravity. 展开更多
关键词 AdS black hole phase transition triple point
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A Novel Derivation of Black Hole Entropy in all Dimensions from Truly Point Mass Sources
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作者 Carlos Castro Perelman 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期1017-1028,共12页
It is explicitly shown how the Schwarzschild Black Hole Entropy (in all dimensions) emerges from truly point mass sources at r=0due to a non-vanishing scalar curvature involving the Dirac delta distribution. In order ... It is explicitly shown how the Schwarzschild Black Hole Entropy (in all dimensions) emerges from truly point mass sources at r=0due to a non-vanishing scalar curvature involving the Dirac delta distribution. In order to achieve this, one is required to extend the domain of r to negative values −∞≤r≤+∞. It is the density and anisotropic pressure components associated with the point mass delta function source at the origin r=0which furnish the Schwarzschild black hole entropy in all dimensions D≥4after evaluating the Euclidean Einstein-Hilbert action. Two of the most salient results are i) that the observed spacetime dimension D=4is precisely singled out from all the other dimensions when the strong and weak energy conditions are met, and ii) the point mass source described in this work is not the result of a spherically symmetric gravitational collapse of a star as described by the Oppenheimer-Snyder model because we are not neglecting the pressure. As usual, it is required to take the inverse Hawking temperature βHas the length of the circle Sβ1obtained from a compactification of the Euclidean time in thermal field theory which results after a Wick rotation, it=τ, to imaginary time. This approach can be generalized to the Reissner-Nordstrom and Kerr-Newman metrics. The physical implications of this finding warrant further investigation since it suggests a profound connection between the notion of gravitational entropy and spacetime singularities. 展开更多
关键词 General Relativity Black holes ENTROPY Strings
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Enhanced magnetic anisotropy and high hole mobility in magnetic semiconductor Ga_(1-x-y)Fe_(x)Ni_(y)Sb
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作者 Zhi Deng Hailong Wang +5 位作者 Qiqi Wei Lei Liu Hongli Sun Dong Pan Dahai Wei Jianhua Zhao 《Journal of Semiconductors》 EI CAS CSCD 2024年第1期16-21,共6页
(Ga,Fe)Sb is a promising magnetic semiconductor(MS)for spintronic applications because its Curie temperature(T_(C))is above 300 K when the Fe concentration is higher than 20%.However,the anisotropy constant Ku of(Ga,F... (Ga,Fe)Sb is a promising magnetic semiconductor(MS)for spintronic applications because its Curie temperature(T_(C))is above 300 K when the Fe concentration is higher than 20%.However,the anisotropy constant Ku of(Ga,Fe)Sb is below 7.6×10^(3)erg/cm^(3)when Fe concentration is lower than 30%,which is one order of magnitude lower than that of(Ga,Mn)As.To address this issue,we grew Ga_(1-x-y)Fe_(x)Ni_(y)Sb films with almost the same x(≈24%)and different y to characterize their magnetic and electrical transport properties.We found that the magnetic anisotropy of Ga_(0.76-y)Fe_(0.24)Ni_(y)Sb can be enhanced by increasing y,in which Ku is negligible at y=1.7%but increases to 3.8×10^(5)erg/cm^(3)at y=6.1%(T_(C)=354 K).In addition,the hole mobility(μ)of Ga_(1-x-y)Fe_(x)Ni_(y)Sb reaches 31.3 cm^(2)/(V∙s)at x=23.7%,y=1.7%(T_(C)=319 K),which is much higher than the mobility of Ga_(1-x)Fe_(x)Sb at x=25.2%(μ=6.2 cm^(2)/(V∙s)).Our results provide useful information for enhancing the magnetic anisotropy and hole mobility of(Ga,Fe)Sb by using Ni co-doping. 展开更多
关键词 magnetic semiconductor molecular beam epitaxy Fe-Ni co-doping magnetic anisotropy hole mobility
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Thermodynamics in a quantum corrected Reissner-Nordstr?m-AdS black hole and its GUP-corrections
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作者 宋建君 刘成周 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期345-353,共9页
We calculate the thermodynamic quantities in the quantum corrected Reissner-Nordstr?m-AdS(RN-AdS)black hole,and examine their quantum corrections.By analyzing the mass and heat capacity,we give the critical state and ... We calculate the thermodynamic quantities in the quantum corrected Reissner-Nordstr?m-AdS(RN-AdS)black hole,and examine their quantum corrections.By analyzing the mass and heat capacity,we give the critical state and the remnant state,respectively,and discuss their consistency.Then,we investigate the quantum tunneling from the event horizon of massless scalar particle by using the null geodesic method,and charged massive boson W^(±)and fermions by using the Hamilton-Jacob method.It is shown that the same Hawking temperature can be obtained from these tunneling processes of different particles and methods.Next,by using the generalized uncertainty principle(GUP),we study the quantum corrections to the tunneling and the temperature.Then the logarithmic correction to the black hole entropy is obtained. 展开更多
关键词 black hole thermodynamics quantum corrections quantum tunneling generalized uncertainty principle
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Timing and Spectral Analysis of the Black Hole X-Ray Binary MAXI J1803-298 with Insight-HXMT Data
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作者 Ying-Chen Xu Jin-Lu Qu +6 位作者 MMéndez Rui-Can Ma Long Ji Liang Zhang Yue Huang Qing-Cui Bu Li-Ming Song 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第6期209-224,共16页
We present a comprehensive analysis of the 2021 outburst of MAXI J1803–298 utilizing observations of the Insight-Hard X-ray Modulation Telescope(Insight-HXMT)spanning from the low hard state to the high soft state.Wi... We present a comprehensive analysis of the 2021 outburst of MAXI J1803–298 utilizing observations of the Insight-Hard X-ray Modulation Telescope(Insight-HXMT)spanning from the low hard state to the high soft state.Within the Insight-HXMT data set,compared to the previous work,we identify a more prolonged presence of typeC quasi-periodic oscillations(QPOs)with centroid frequencies ranging from~0.16 to 6.3 Hz,which present correlations with the hardness ratio and the photon index of the Comptonized component.For QPO frequencies less than~2 Hz,the QPO phase lags are hard(photons of 10–19 keV arrive later than those of 1–4 keV),while at higher frequencies,the lags become soft at and above~4 Hz.Furthermore,the spectra in all Insight-HXMT observations consist of a multi-color blackbody component and a Comptonized component,as commonly observed in classical black hole X-ray binaries.We analyze state transitions and the evolution of accretion geometry in this work.The fitted inner disk radius increases abnormally during the low hard state,hypothesized to result from the corona condensing onto the inner disk.Additionally,two significant drops in flux are observed during the soft intermediate state,maybe implying changes in the corona/jet and the disk,respectively. 展开更多
关键词 X-rays:binaries ACCRETION accretion disks stars:black holes
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Generalized Newton’s Theory of Universal Gravitation and Black Holes
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作者 Lenser Aghalovyan 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期126-137,共12页
The Newton’s theory of universal gravitation is generalized. Significantly strong at short distances central interaction of bodies and particles is established in comparison with Newtonian. A connection is found with... The Newton’s theory of universal gravitation is generalized. Significantly strong at short distances central interaction of bodies and particles is established in comparison with Newtonian. A connection is found with Black Holes, with the horizon of events. Possibility of systematization of all Black Holes is shown. An illustration is given on the example of Black Hole S<sub>gr</sub>A*. 展开更多
关键词 GRAVITATION Central Interaction Escape Velocity Black hole Horizon of Events
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Retinal displacement after surgery for idiopathic macular hole
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作者 He-Cong Qin Fu-Qiang Li +1 位作者 Si-Yan Jin Jin-Song Zhao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第8期1545-1556,共12页
AIM:To review and summarize the mechanism hypothesis,influencing factors and possible consequences of macular retinal displacement after idiopathic macular hole(IMH)surgery.METHODS:PubMed and Web of Science database w... AIM:To review and summarize the mechanism hypothesis,influencing factors and possible consequences of macular retinal displacement after idiopathic macular hole(IMH)surgery.METHODS:PubMed and Web of Science database was searched for studies published before April 2023 on“Retinal displacement”,“Idiopathic macular holes”,and“Macular displacement”.RESULTS:Recently,more academics have begun to focus on retinal displacement following idiopathic macular holes.They found that internal limiting membrane(ILM)peeling was the main cause of inducing postoperative position shift in the macular region.Moreover,several studies have revealed that the macular hole itself,as well as ILM peeling method,will have an impact on the result.In addition,this phenomenon is related to postoperative changes in macular retinal thickness,cone outer segment tips line recovery,the occurrence of dissociated optic nerve fiber layer(DONFL)and the degree of metamorphopsia.CONCLUSION:As a subclinical phenomenon,the clinical significance of postoperative macular displacement cannot be underestimated as it may affect the recovery of anatomy and function. 展开更多
关键词 idiopathic macular holes internal limiting membrane peeling retina displacement
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Investigation on photonic crystal nanobeam cavity based on mixed diamond–circular holes
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作者 Jingtong Bin Kerui Feng +4 位作者 Shang Ma Ke Liu Yong Cheng Jing Chen Qifa Liu 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第1期63-70,共8页
A photonic crystal nanobeam cavity(M-PCNC)with a structure incorporating a mixture of diamond-shaped and circular air holes is pro-posed.The performance of the cavity is simulated and studied theoretically.Using thefin... A photonic crystal nanobeam cavity(M-PCNC)with a structure incorporating a mixture of diamond-shaped and circular air holes is pro-posed.The performance of the cavity is simulated and studied theoretically.Using thefinite-difference time-domain method,the parameters of the M-PCNC,including cavity thickness and width,lattice constant,and radii and numbers of holes,are optimized,with the quality factor Q and mode volume Vm as performance indicators.Mutual modulation of the lattice constant and hole radius enable the proposed M-PCNC to realize outstanding performance.The optimized cavity possesses a high quality factor Q 1.45105 and an ultra-small mode=×volume Vm 0.01(λ/n)[Zeng et al.,Opt Lett 2023:48;3981–3984]in the telecommunications wavelength range.Light can be progres-=sively squeezed in both the propagation direction and the perpendicular in-plane direction by a series of interlocked anti-slots and slots in the diamond-shaped hole structure.Thereby,the energy can be confined within a small mode volume to achieve an ultra-high Q/Vm ratio. 展开更多
关键词 Photonic crystal nanobeam cavity Mixed diamond–circular holes Slots and anti-slots FDTD simulation Quality factor Mode volume
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Quantum Unruh Effect on Radiation of Black Holes
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作者 Tianxi Zhang 《Journal of Modern Physics》 2024年第6期938-949,共12页
The quantum Unruh effect on radiation of a gravitational object including a black hole is analyzed and calculated. It is surprisingly found that the well-known Hawking radiation of a black hole is not physical. Applyi... The quantum Unruh effect on radiation of a gravitational object including a black hole is analyzed and calculated. It is surprisingly found that the well-known Hawking radiation of a black hole is not physical. Applying the Stephan-Boltzmann law with the use of the Unruh radiation temperature at the surface of a black hole to calculate the power of radiation of the black hole is conceptually unphysical. This is because the Unruh radiation temperature results from the gravitational field of the object rather than from the thermal motion of matter of the object, so that the Stephan-Boltzmann law is not applicable. This paper shows that the emission power of Unruh radiation from a gravitational object should be calculated in terms of the rate of increase of the total Unruh radiation energy outside the object. The result obtained from this study indicates that a gravitational object can emit Unruh radiation when the variation of its mass and radius satisfies an inequality of dM/M > 1.25dR/R. For a black hole, the emission of Unruh radiation does not occur unless it can loose its mass (dM < 0). The emission power of Unruh radiation is only an extremely tiny part of the rate of mass-energy loss if the black hole is not extremely micro-sized. This study turns down our traditional understanding of the Hawking radiation and thermodynamics of black holes. 展开更多
关键词 Black hole GRAVITATION Quantum Field Theory Blackbody Radiation
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Black Hole Singularities and Planetary Formation
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作者 Louise Riofrio 《Journal of Applied Mathematics and Physics》 2024年第4期1079-1088,共10页
The goal of this research is to explore the effects of black hole singularities. Methodology is to start with large objects like galaxies and continue to smaller objects within our solar neighbourhood. High-redshift o... The goal of this research is to explore the effects of black hole singularities. Methodology is to start with large objects like galaxies and continue to smaller objects within our solar neighbourhood. High-redshift observations from the James Webb Space Telescope reveal that distant galaxies and their central black holes formed shortly after the Big Bang. An innovation about the speed of light explains how supermassive black holes could have formed primordially. Predictions of Hawking radiation include the possibility of black holes contributing to the energy of stars such as the Sun. Black holes have also been suggested as a source of radiation and magnetic fields in giant planets. Observations of Enceladus raise the possibility that this moon and other objects near Saturn’s Rings contain small singularities. Extrapolations of this methodology indicate that black holes could exist within solar system bodies including planets. Extended discussion describes how their presence could explain mysteries of internal heat, planetary magnetic fields, and processes of solar system formation. 展开更多
关键词 Black holes GALAXIES Magnetic Fields Planets Planetary Formation Speed of Light
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On Our Peculiar Black Hole Universe
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作者 Paolo Christillin 《Journal of Modern Physics》 2024年第2期179-183,共5页
The black hole model of the Universe evolution, accompanied by matter creation, already successfully accounting for many features of the past is discussed and further justified. It is once more stressed that even a ve... The black hole model of the Universe evolution, accompanied by matter creation, already successfully accounting for many features of the past is discussed and further justified. It is once more stressed that even a very large object but with a big mass is in its own right a black hole. As a consequence, the extrapolation of the past predicts for the future no big crunch, nor big bounce but a steady expansion with smaller matter density. 展开更多
关键词 Universe Expansion Black hole Model Matter Creation Gravitational Self Energy
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Black Hole Complementarity in Terms of the Outsider and Insider Perspectives
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作者 Eugene Terry Tatum 《Journal of Modern Physics》 2024年第2期184-192,共9页
A complementarity hypothesis concerning outsider and insider perspectives of a gargantuan black hole is proposed. The two thought experiments presented herein are followed by a brief discussion of a new interpretation... A complementarity hypothesis concerning outsider and insider perspectives of a gargantuan black hole is proposed. The two thought experiments presented herein are followed by a brief discussion of a new interpretation of black hole interior “space-and-time-reversal”. Specifically, it is proposed that the “singularity” space of the black hole interior is time-like and the expansion time of the black hole interior is space-like. The resemblance of this new insider interpretation to our own expanding and redshifting big bang universe is compelling. 展开更多
关键词 Black holes Complementarity Cosmological Models Rh = ct Models Flat Space Cosmology Schwarzschild Cosmology Thought Experiment Dark Energy Quantum Vacuum
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Research and Application of Advanced Detection of Water Hazards in Coal Mine Bore-Hole
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作者 Libo Deng 《Engineering(科研)》 2024年第7期181-187,共7页
For many years, the “short excavation and short exploration” excavation mode has been mainly used in the underground tunnel excavation of coal mines, which is difficult to meet the needs of rapid tunnel excavation. ... For many years, the “short excavation and short exploration” excavation mode has been mainly used in the underground tunnel excavation of coal mines, which is difficult to meet the needs of rapid tunnel excavation. For this reason, CCTEG Xi’an Research Institute has innovatively proposed a new working mode of “long excavation and long exploration” using directional long drilling and borehole geophysical exploration. This method utilizes directional long boreholes that have already been constructed, and uses transient electromagnetic technology in the borehole to detect the radial range of 30 meters and the depth exceeding 1000 meters of the borehole, ultimately forming a three-dimensional imaging of the entire spatial geological anomaly body, providing reliable technical support for the safety and long-term excavation of the tunnel. This paper introduces the application which is a long-distance advanced detection of 1026 m. . 展开更多
关键词 Transient Electromagnetic Method Bore-hole Transient Electromagnetic TEM Geophysical Exploration
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后路单开门钉板固定结合Key-hole技术在混合型颈椎病患者中的应用效果
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作者 王晓刚 《黑龙江医药科学》 2024年第4期90-92,共3页
目的:分析后路单开门钉板固定结合Key-hole技术在混合型颈椎病患者中的应用效果。方法:采用前瞻性分析法,以随机数表法将2021年6月至2023年6月濮阳市人民医院120例混合型颈椎病患者分为对照组和观察组,各60例。对照组患者采用后路单开... 目的:分析后路单开门钉板固定结合Key-hole技术在混合型颈椎病患者中的应用效果。方法:采用前瞻性分析法,以随机数表法将2021年6月至2023年6月濮阳市人民医院120例混合型颈椎病患者分为对照组和观察组,各60例。对照组患者采用后路单开门钉板固定治疗,观察组患者采用后路单开门钉板固定结合Key-hole技术治疗。对两组患者术前和术后3个月的JOA评分、JOA评分改善率、Cobb角、ROM、颈椎肌张力及术后3个月的并发症情况进行比较。结果:与对照组相比,术后观察组的JOA评分、JOA评分改善率均升高,术后观察组的Cobb角、ROM、颈椎肌张力均升高,术后3个月观察组的神经根症状总有效率升高,术后3个月内观察组的并发症总发生率降低,差异有统计学意义(P<0.05)。结论:后路单开门钉板固定结合Key-hole技术能够有效缓解混合型颈椎病患者的颈髓、神经根压迫,改善颈髓、神经根功能,且可减少并发症发生。 展开更多
关键词 混合型颈椎病 后路单开门钉板固定 Key-hole技术 疗效
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O型臂导航辅助经皮内镜下Key-hole术式治疗神经根型颈椎病的临床疗效 被引量:1
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作者 潘才成 覃梁圣 +3 位作者 黄珩 贺庆 肖侃侃 卓祥龙 《中国脊柱脊髓杂志》 CAS CSCD 北大核心 2023年第6期523-529,共7页
目的:评价O型臂导航辅助经皮内镜下Key-hole术式治疗单节段神经根型颈椎病(cervical spondylotic radiculopathy,CSR)的临床疗效。方法:回顾性分析2018年9月~2020年6月在我院接受O型臂导航辅助经皮内镜下Key-hole术式治疗的单节段CSR患... 目的:评价O型臂导航辅助经皮内镜下Key-hole术式治疗单节段神经根型颈椎病(cervical spondylotic radiculopathy,CSR)的临床疗效。方法:回顾性分析2018年9月~2020年6月在我院接受O型臂导航辅助经皮内镜下Key-hole术式治疗的单节段CSR患者22例,其中男14例,女8例,年龄54.05±10.67岁(32~71岁);C5/6节段8例,C6/7节段13例,C7/T1节段1例。记录手术时间、术中出血量、术后住院时间及并发症情况;术前、术后3d及末次随访时采用视觉模拟评分量表(visual analogue scale,VAS)、颈部功能障碍指数(neck disability index,NDI)进行疼痛和功能评定,末次随访时根据改良Macnab标准评定疗效;术前、术后3d及末次随访时进行X线片、CT及MRI检查,测量手术节段椎间隙高度(disc height,DH)、下颈椎曲度(cervical spinal angle,CSA)及侧块关节平面切除率(facet resection rate,FRR)。结果:所有患者手术均顺利完成,随访时间36.85±5.83个月(25~44个月)。手术时间为120.32±33.92mins(76~209mins),术中出血量为14.86±12.67ml(2~50ml),术后住院时间为4.05±1.70d(2~9d)。手术并发症3例,其中1例术中C7神经根损伤致右肱三头肌肌力明显下降至2级,末次随访时肌力恢复至5级;1例术中发生椎动脉钳夹损伤出血,即刻使用凝胶海绵填塞止血,术后影像学显示无血肿形成,未诉特殊不适;1例术后出现轻度神经放射痛,经药物治疗后改善。与术前相比,术后3d、末次随访时颈痛VAS评分及NDI均得到显著改善(P<0.05);末次随访时改良MacNab标准评分优17例、良4例、可1例,优良率为95.5%。术前、术后3d及末次随访时DH分别为4.40±0.97mm、4.31±0.92mm及4.26±1.01mm,CSA分别为5.70°±16.94°、8.43°±15.59°及11.44°±13.80°,术前、术后3d及末次随访时DH及CSA相比较,差异均无统计学意义(P>0.05)。FRR为(27.12±16.62)%。结论:O型臂导航辅助经皮内镜下Key-hole术式治疗CSR安全有效,具有工作套管精准置入,降低手术损伤的优点。 展开更多
关键词 神经根型颈椎病 O型臂导航 脊柱内镜 Key-hole术式
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Gelation of Hole Transport Layer to Improve the Stability of Perovskite Solar Cells 被引量:1
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作者 Ying Zhang Chenxiao Zhou +7 位作者 Lizhi Lin Fengtao Pei Mengqi Xiao Xiaoyan Yang Guizhou Yuan Cheng Zhu Yu Chen Qi Chen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第10期305-316,共12页
To achieve high power conversion efficiency(PCE) and long-term stability of perovskite solar cells(PSCs), a hole transport layer(HTL) with persistently high conductivity, good moisture/oxygen barrier ability, and adeq... To achieve high power conversion efficiency(PCE) and long-term stability of perovskite solar cells(PSCs), a hole transport layer(HTL) with persistently high conductivity, good moisture/oxygen barrier ability, and adequate passivation capability is important. To achieve enough conductivity and effective hole extraction, spiro-OMe TAD, one of the most frequently used HTL in optoelectronic devices, often needs chemical doping with a lithium compound(LiTFSI). However, the lithium salt dopant induces crystallization and has a negative impact on the performance and lifetime of the device due to its hygroscopic nature. Here, we provide an easy method for creating a gel by mixing a natural small molecule additive(thioctic acid, TA) with spiro-OMe TAD. We discover that gelation effectively improves the compactness of resultant HTL and prevents moisture and oxygen infiltration. Moreover, the gelation of HTL improves not only the conductivity of spiro-OMe TAD, but also the operational robustness of the devices in the atmospheric environment. In addition, TA passivates the perovskite defects and facilitates the charge transfer from the perovskite layer to HTL. As a consequence, the optimized PSCs based on the gelated HTL exhibit an improved PCE(22.52%) with excellent device stability. 展开更多
关键词 Perovskite solar cell hole transport layer GELATION Humidity stability Aggregation of LiTFSI
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Stress release mechanism of deep bottom hole rock by ultra-high-pressure water jet slotting 被引量:1
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作者 Hua-jian Wang Hua-Lin Liao +6 位作者 Jun Wei Jian-Sheng Liu Wen-Long Niu Yong-Wang Liu Zhi-Chuan Guan Hedi Sllami John-Paul Latham 《Petroleum Science》 SCIE EI CAS CSCD 2023年第3期1828-1842,共15页
To solve the problems of rock strength increase caused by high in-situ stress,the stress release method with rock slot in the bottom hole by an ultra-high-pressure water jet is proposed.The stress conditions of bottom... To solve the problems of rock strength increase caused by high in-situ stress,the stress release method with rock slot in the bottom hole by an ultra-high-pressure water jet is proposed.The stress conditions of bottom hole rock,before and after slotting are analyzed and the stress release mechanism of slotting is clarified.The results show that the stress release by slotting is due to the coupling of three factors:the relief of horizontal stress,the stress concentration zone distancing away from the cutting face,and the increase of pore pressure caused by rock mass expansion;The stress concentration increases the effective stress of rock along the radial distance from O.6R to 1R(R is the radius of the well),and the presence of groove completely releases the stress,it also allows the stress concentration zone to be pushed away from the cutting face,while significantly lowering the value of stresses in the area the drilling bit acting,the maximum stress release efficiency can reach 80%.The effect of slotting characteristics on release efficiency is obvious when the groove location is near the borehole wall.With the increase of groove depth,the stress release efficiency is significantly increased,and the release range of effective stress is enlarged along the axial direction.Therefore,the stress release method and results of simulations in this paper have a guiding significance for best-improving rock-breaking efficiency and further understanding the technique. 展开更多
关键词 Hard rock SLOTTING Stress release Down hole pressures Poroelastic mechanics Fluid-structure Interaction Ultra-high-pressure water jet
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