Background:Enhanced depth-of-focus intraocular lenses(EDOF IOL)have filled the gap between monofocal and multifocal intraocular implants with optical qualities of monofocal lenses and usually minor dysphotopsias typic...Background:Enhanced depth-of-focus intraocular lenses(EDOF IOL)have filled the gap between monofocal and multifocal intraocular implants with optical qualities of monofocal lenses and usually minor dysphotopsias typical for multifocal lenses.The purpose of this study was to evaluate visual outcomes after bilateral implantation of a new EDOF IOL in patients with requirements for perfect near and intermediate vision.Methods:The study included 15 patients(29 eyes as one was amblyopic)with bilateral implantation of LUXSMART EDOF IOL(Bausch&Lomb)with a targeted myopia(between-0.25 and-0.50D)in both eyes.Monocular corrected and uncorrected visual acuity for far,intermediate and near as well as refractive outcomes were evaluated at 1,3,6 and 12 months after the surgery.Additionally,binocular visual acuity,contrast sensitivity and defocus curve were measured at the final follow-up visit.At 12 months’visit patients completed a questionnaire evaluating patient satisfaction,spectacle independence and presence of dysphotopsias.Results:Binocular uncorrected visual acuities at 12 month’s visit were 0.13±0.16,0.06±0.08,0.07±0.09 and 0.15±0.09 logMAR for far distance,80 cm,66 cm and 40 cm respectively.Corrected binocular visual acuities at 12 months were 0.00±0.00,0.05±0.07,0.05±0.06,0.13±0.16 respectively for distance,80 cm,66 cm and 40 cm.Automated refraction spherical equivalent at 12 months’visit stood at-0.70±0.48D,which was 0.46D less than calculated biometric target,however spherical equivalent of subjective refraction at 12 months equaled–0.49±0.46D,which was closer to preoperative biometric target.Defocus curve had gentle shape without peaks typical for monofocal IOLs.Binocular contrast sensitivity results were superior to average results for that age group and equaled 1.78±0.16 logMAR without correction and 1.81±0.13 logMAR with correction.Spectacle independence for near and intermediate distances was achieved in all patients and for far distance in 73.3%of patients.Burdensome dysphotopsias were not reported in any case.Conclusions:EDOF IOLs targeted bilaterally at low myopia can provide excellent near and intermediate visual acuity and independence of any optical correction in majority of cases.This approach can be used in selected patients who are focused on stationary activities.展开更多
Spinal cord injury（SCI） affects thousands of people every year in the USA, and most patients are left with some permanent paralysis. Therapeutic options are limited and only modestly affect outcome. To address this ...Spinal cord injury（SCI） affects thousands of people every year in the USA, and most patients are left with some permanent paralysis. Therapeutic options are limited and only modestly affect outcome. To address this issue, we used magnetic resonance imaging-guided focused ultrasound（MRg FUS） as a non-invasive approach to increase permeability in the blood-spinal cord barrier（BSCB）. We hypothesize that localized, controlled sonoporation of the BSCB by MRg FUS will aid delivery of therapeutics to the injury. Here, we report our preliminary findings for the ability of MRg FUS to increase BSCB permeability in the thoracic spinal cord of a normal rat model. First, an excised portion of normal rat spinal column was used to characterize the acoustic field and to estimate the insertion losses that could be expected in an MRg FUS blood spinal cord barrier opening. Then, in normal rats, MRg FUS was applied in combination with intravenously administered microbubbles to the spinal cord region. Permeability of the BSCB was indicated as signal enhancement by contrast administered prior to T1-weighted magnetic resonance imaging and verified by Evans blue dye. Neurological testing using the Basso, Beattie, and Breshnahan scale and the ladder walk was normal in 8 of 10 rats tested. Two rats showed minor impairment indicating need for further refinement of parameters. No gross tissue damage was evident by histology. In this study, we have opened successfully the blood spinal cord barrier in the thoracic region of the normal rat spine using magnetic resonance-guided focused ultrasound combined with microbubbles.展开更多
Existing conventional megajoule plasma focus machines with 2–3 MA are producing fusion neutron yields of several times 10^(11) in deuterium operation,the fusion yields predominantly being the beam-gas target.Increasi...Existing conventional megajoule plasma focus machines with 2–3 MA are producing fusion neutron yields of several times 10^(11) in deuterium operation,the fusion yields predominantly being the beam-gas target.Increasing the current to 10 MA and using 50%–50%D-T mixture will scale the neutron yield towards 10^(16) D-T fusion neutrons.In this work,we derive the Lawson criterion for plasma focus devices with a beam-target fusion neutron mechanism,so that we may glimpse what future technological advancements are needed for a break-even Q=1 plasma focus.We perform numerical experiments with a present-day feasible 0.9 MV,8.1 MJ,11 MA machine operating in 100 Torr in 50%–50%D-T mixture.The Lee Code simulation gives a detailed description of the plasma focus dynamics through each phase,and provides plasma and yield parameters which show that out of 1.1×10^(19) fast beam ions produced in the plasma focus pinch,only 1.24×10^(14) ions take part in beam-target fusion reactions within the pinch,producing the same number of D-T neutrons.The remnant beam ions,numbering at least 10^(19),exit the focus pinch at 1.9 MeV,which is far above the 115 keV ion energy necessary for an optimum beam-target cross-section.We propose to regain the lost fusion rates by using a high-pressure D-T-filled drift-tube to attenuate the energy of the remnant beam ions until they reach the energy for the optimum fusion cross-section.Such a fusion enhancement tube would further harvest beam-target fusion reactions by increasing the interaction path length(1 m)at increased interaction density(6 atm).A gain factor of 300 is conservatively estimated,with a final yield of 3.7×10^(16) D-T neutrons carrying kinetic energy of 83.6 kJ,demonstrating Q=0.01.展开更多
Benefiting from the induced image charge on film surface,the nanoparticle aggregating on metal exhibits interesting optical properties.In this work,a linear metal nanoparticle trimer on metal film system has been inve...Benefiting from the induced image charge on film surface,the nanoparticle aggregating on metal exhibits interesting optical properties.In this work,a linear metal nanoparticle trimer on metal film system has been investigated to explore the novel optical phenomenon.Both the electric field and surface charge distributions demonstrate the light is focused on film greatly by the nanoparticles at two sides,which could be strongly modulated by the wavelength of incident light.And the influence of nanoparticle in middle on this light focusing ability has also been studied here,which is explained by the plasmon hybridization theory.Our finding about light focusing in nanoparticle aggregating on metal film not only enlarges the novel phenomenon of surface plasmon but also has great application prospect in the field of surface-enhanced spectra,surface catalysis,solar cells,water splitting,etc.展开更多
目的 探讨动态增强磁共振成像(Dynamic Contrast-Enhanced MRI,DCE-MRI)定量参数在子宫肌瘤患者下腹部皮下脂肪微循环特点研究中的应用价值。方法 收集71例接受高强度聚焦超声治疗的子宫肌瘤患者的术前DCE-MRI图像,采用盆腔轴位动态增强...目的 探讨动态增强磁共振成像(Dynamic Contrast-Enhanced MRI,DCE-MRI)定量参数在子宫肌瘤患者下腹部皮下脂肪微循环特点研究中的应用价值。方法 收集71例接受高强度聚焦超声治疗的子宫肌瘤患者的术前DCE-MRI图像,采用盆腔轴位动态增强LAVA序列进行感兴趣区(Region of Interest,ROI)勾画,取轴位上两侧髂结节所作结节间平面为初始层面进行测量,共测量3个平面,于各层面左右两侧分别进行测量,每例患者均测量18个ROI,计算各ROI皮下脂肪定量参数:容积转运常数(Volume Transfer Constant,Ktrans)、速率常数(Rate Constant,Kep)、血管外细胞外间隙容积分数(Extravascular Extracellular Space Volume Fraction Per Unit of Tissue Volume,Ve)以及血浆容积指数(Blood Plasma Volume Per Unit Volume of Tissue,Vp)。结果 每一层各点的Ktrans、Kep、Ve值差异有统计学意义(P<0.05),且均表现为:点1>点2>点3,两点间差异有统计学意义(P<0.05);L1、L2层的Vp值差异有统计学意义(P<0.05),R1~R3及L3层Vp值差异均无统计学意义。结论 DEC-MRI可以通过定量参数量化皮下脂肪微循环的情况,不同位置皮下脂肪微循环情况有差异,各层靠近腹部中心区域的微循环较外周区域丰富。展开更多
文摘Background:Enhanced depth-of-focus intraocular lenses(EDOF IOL)have filled the gap between monofocal and multifocal intraocular implants with optical qualities of monofocal lenses and usually minor dysphotopsias typical for multifocal lenses.The purpose of this study was to evaluate visual outcomes after bilateral implantation of a new EDOF IOL in patients with requirements for perfect near and intermediate vision.Methods:The study included 15 patients(29 eyes as one was amblyopic)with bilateral implantation of LUXSMART EDOF IOL(Bausch&Lomb)with a targeted myopia(between-0.25 and-0.50D)in both eyes.Monocular corrected and uncorrected visual acuity for far,intermediate and near as well as refractive outcomes were evaluated at 1,3,6 and 12 months after the surgery.Additionally,binocular visual acuity,contrast sensitivity and defocus curve were measured at the final follow-up visit.At 12 months’visit patients completed a questionnaire evaluating patient satisfaction,spectacle independence and presence of dysphotopsias.Results:Binocular uncorrected visual acuities at 12 month’s visit were 0.13±0.16,0.06±0.08,0.07±0.09 and 0.15±0.09 logMAR for far distance,80 cm,66 cm and 40 cm respectively.Corrected binocular visual acuities at 12 months were 0.00±0.00,0.05±0.07,0.05±0.06,0.13±0.16 respectively for distance,80 cm,66 cm and 40 cm.Automated refraction spherical equivalent at 12 months’visit stood at-0.70±0.48D,which was 0.46D less than calculated biometric target,however spherical equivalent of subjective refraction at 12 months equaled–0.49±0.46D,which was closer to preoperative biometric target.Defocus curve had gentle shape without peaks typical for monofocal IOLs.Binocular contrast sensitivity results were superior to average results for that age group and equaled 1.78±0.16 logMAR without correction and 1.81±0.13 logMAR with correction.Spectacle independence for near and intermediate distances was achieved in all patients and for far distance in 73.3%of patients.Burdensome dysphotopsias were not reported in any case.Conclusions:EDOF IOLs targeted bilaterally at low myopia can provide excellent near and intermediate visual acuity and independence of any optical correction in majority of cases.This approach can be used in selected patients who are focused on stationary activities.
基金supported by the University of Utah RadiologyNeuroscience Initiative Pilot grantthe Department of Neurosurgery pilot fund
文摘Spinal cord injury（SCI） affects thousands of people every year in the USA, and most patients are left with some permanent paralysis. Therapeutic options are limited and only modestly affect outcome. To address this issue, we used magnetic resonance imaging-guided focused ultrasound（MRg FUS） as a non-invasive approach to increase permeability in the blood-spinal cord barrier（BSCB）. We hypothesize that localized, controlled sonoporation of the BSCB by MRg FUS will aid delivery of therapeutics to the injury. Here, we report our preliminary findings for the ability of MRg FUS to increase BSCB permeability in the thoracic spinal cord of a normal rat model. First, an excised portion of normal rat spinal column was used to characterize the acoustic field and to estimate the insertion losses that could be expected in an MRg FUS blood spinal cord barrier opening. Then, in normal rats, MRg FUS was applied in combination with intravenously administered microbubbles to the spinal cord region. Permeability of the BSCB was indicated as signal enhancement by contrast administered prior to T1-weighted magnetic resonance imaging and verified by Evans blue dye. Neurological testing using the Basso, Beattie, and Breshnahan scale and the ladder walk was normal in 8 of 10 rats tested. Two rats showed minor impairment indicating need for further refinement of parameters. No gross tissue damage was evident by histology. In this study, we have opened successfully the blood spinal cord barrier in the thoracic region of the normal rat spine using magnetic resonance-guided focused ultrasound combined with microbubbles.
文摘Existing conventional megajoule plasma focus machines with 2–3 MA are producing fusion neutron yields of several times 10^(11) in deuterium operation,the fusion yields predominantly being the beam-gas target.Increasing the current to 10 MA and using 50%–50%D-T mixture will scale the neutron yield towards 10^(16) D-T fusion neutrons.In this work,we derive the Lawson criterion for plasma focus devices with a beam-target fusion neutron mechanism,so that we may glimpse what future technological advancements are needed for a break-even Q=1 plasma focus.We perform numerical experiments with a present-day feasible 0.9 MV,8.1 MJ,11 MA machine operating in 100 Torr in 50%–50%D-T mixture.The Lee Code simulation gives a detailed description of the plasma focus dynamics through each phase,and provides plasma and yield parameters which show that out of 1.1×10^(19) fast beam ions produced in the plasma focus pinch,only 1.24×10^(14) ions take part in beam-target fusion reactions within the pinch,producing the same number of D-T neutrons.The remnant beam ions,numbering at least 10^(19),exit the focus pinch at 1.9 MeV,which is far above the 115 keV ion energy necessary for an optimum beam-target cross-section.We propose to regain the lost fusion rates by using a high-pressure D-T-filled drift-tube to attenuate the energy of the remnant beam ions until they reach the energy for the optimum fusion cross-section.Such a fusion enhancement tube would further harvest beam-target fusion reactions by increasing the interaction path length(1 m)at increased interaction density(6 atm).A gain factor of 300 is conservatively estimated,with a final yield of 3.7×10^(16) D-T neutrons carrying kinetic energy of 83.6 kJ,demonstrating Q=0.01.
基金the National Key Research and Development Program(Grant No.2019YFC1906100)the National Natural Science Foundation of China(Grant Nos.11974067 and 12074054)+1 种基金the Natural Science Foundation Project of CQ CSTC(cstc2019jcyj-msxmX0145,cstc2019jcyj-bshX0042,and cstc2019jcyj-msxmX0828)the Sharing Fund of Chongqing University’s Large-scale Equipment.
文摘Benefiting from the induced image charge on film surface,the nanoparticle aggregating on metal exhibits interesting optical properties.In this work,a linear metal nanoparticle trimer on metal film system has been investigated to explore the novel optical phenomenon.Both the electric field and surface charge distributions demonstrate the light is focused on film greatly by the nanoparticles at two sides,which could be strongly modulated by the wavelength of incident light.And the influence of nanoparticle in middle on this light focusing ability has also been studied here,which is explained by the plasmon hybridization theory.Our finding about light focusing in nanoparticle aggregating on metal film not only enlarges the novel phenomenon of surface plasmon but also has great application prospect in the field of surface-enhanced spectra,surface catalysis,solar cells,water splitting,etc.
文摘目的 探讨动态增强磁共振成像(Dynamic Contrast-Enhanced MRI,DCE-MRI)定量参数在子宫肌瘤患者下腹部皮下脂肪微循环特点研究中的应用价值。方法 收集71例接受高强度聚焦超声治疗的子宫肌瘤患者的术前DCE-MRI图像,采用盆腔轴位动态增强LAVA序列进行感兴趣区(Region of Interest,ROI)勾画,取轴位上两侧髂结节所作结节间平面为初始层面进行测量,共测量3个平面,于各层面左右两侧分别进行测量,每例患者均测量18个ROI,计算各ROI皮下脂肪定量参数:容积转运常数(Volume Transfer Constant,Ktrans)、速率常数(Rate Constant,Kep)、血管外细胞外间隙容积分数(Extravascular Extracellular Space Volume Fraction Per Unit of Tissue Volume,Ve)以及血浆容积指数(Blood Plasma Volume Per Unit Volume of Tissue,Vp)。结果 每一层各点的Ktrans、Kep、Ve值差异有统计学意义(P<0.05),且均表现为:点1>点2>点3,两点间差异有统计学意义(P<0.05);L1、L2层的Vp值差异有统计学意义(P<0.05),R1~R3及L3层Vp值差异均无统计学意义。结论 DEC-MRI可以通过定量参数量化皮下脂肪微循环的情况,不同位置皮下脂肪微循环情况有差异,各层靠近腹部中心区域的微循环较外周区域丰富。
