ELECTRORHEOLOGICAL PROPERTIES OF TALC POWDER/SILICONE OIL SUSPENSIONS UNDER DC FIELDS

In this study, the electrorheological （ER） behavior of suspensions prepared from d50 = 2.4 lam talc powder, dispersed in insulating silicone oil （SO） medium was investigated. Sedimentation stabilities of suspensions （c = 5 wt%） prepared using these talc powder powders were determined to be 78 days. The ER activity of all the suspensions was observed to increase with increasing electric field strength, concentration and decreasing shear rate. The shear stress of talc powder suspensions increased linearly with increasing concentrations of the particles and with the applied electric field strength. Electric field viscosity of all the suspensions decreased sharply with increasing shear rate and showed a typical shear thinning non-Newtonian visco-elastic behavior. Effects of frequency on the ER activity of talc powder/SO system were also investigated.

Silicone oil as a corneal lubricant to reduce corneal edema and improve visualization during

AIM:To evaluate the efficacy and safety of silicone oil(SO)as a corneal lubricant to improve visualization during vitrectomy.METHODS:Patients who underwent vitreoretinal surgery were divided into two groups.Group 1 was operated on with initial SO(Oxane 5700)as a corneal lubricant.Group 2 was operated on with initial lactated ringer’s solution(LRS)and then replaced with SO as required.Fundus clarity was scored during the surgery.Fluorescein staining was performed to determine the damage to corneal epithelium.RESULTS:Totally 114 eyes of 114 patients were included.Single SO use maintained a clear cornea and provided excellent visualization of surgical image.In group 1,the fundus clarity was grade 3 in 41/45 eyes and grade 2 in 4/45 eyes.In group 2,corneal edema frequently occurred after initial LRS use.The fundus clarity was grade 3 in 19/69 eyes,2 in 37/69 eyes and 1 in 13/69 eyes(P<0.05).SO was applied in 29 eyes of initial LRS use with subsequent corneal edema,which eliminated the corneal edema in 26 eyes.Corneal fluorescein staining score in group 1 was 0 in 28 eyes,1 in 11 eyes and 2 in 6 eyes,and 40,20 and 9,respectively,in group 2(all P>0.05).CONCLUSION:The use of SO as a corneal lubricant is effective and safe for preserving and improving corneal clarity and providing clear surgical field during vitrectomy.

Non-contact wide-field viewing system-assisted scleral buckling surgery for retinal detachment in silicone oilfilled eyes

AIM:To evaluate scleral buckling(SB)surgery using a noncontact wide-field viewing system and 23-gauge intraocular illumination for the treatment of rhegmatogenous retinal detachment in silicone oil(SO)-filled eyes.METHODS:Totally 9 patients(9 eyes)with retinal detachment in SO-filled eyes were retrospectively analyzed.All patients underwent non-contact wide-field viewing system-assisted buckling surgery with 23-gauge intraocular illumination.SO was removed at an appropriate time based on recovery.The patients were followed up for at least 3mo after SO removal.Retinal reattachment,complications,visual acuity and intraocular pressure(IOP)before and after surgery were observed.RESULTS:Patients were followed up for a mean of 8.22mo(3-22mo)after SO removal.All patients had retinal reattachment.At the final follow-up,visual acuity showed improvement for 8 patients,and no change for 1 patient.The IOP was high in 3 patients before surgery,but it stabilized after treatment;it was not affected in the other patients.None of the patients had infections,hemorrhage,anterior ischemia,or any other complication.CONCLUSION:This new non-contact wide-field viewing system-assisted SB surgery with 23-gauge intraocular illumination is effective and safe for retinal detachment in SO-filled eyes.

Endophthalmitis in silicone oil-filled eye: A case report

BACKGROUND Endophthalmitis occurring in silicone oil-filled eyes is a very rare occurrence,with reported incidence rates ranging between 0.07%and 0.039%.Traditional methods of management of infectious endophthalmitis include the removal of silicone oil,washout of the vitreous cavity,administration of intravitreal antibiotics,and reinjection of silicone oil.CASE SUMMARY Herein,we report the case of a 39-year-old man with unilateral endophthalmitis after pars plana vitrectomy and silicone oil tamponade.Intravitreal injections of full-dose antibiotics and anterior chamber washout were used to treat the patient.No signs of retinal toxicity were observed during the follow-up period.CONCLUSION Intravitreal full-dose antibiotic injections and anterior chamber washout are promising alternatives to traditional therapies for endophthalmitis in silicone oilfilled eyes.

Research Progress of Carbon-Silicone Composite Materials

Silicone is a kind of polymer material with high cross-linked structure,which is com-posed by Si-O-Si main chain.Due to the special molecular chain structure,silicone mate-rials are characterized by oxidation resistance,aging resistance,high and low temperature resistance and chemical corrosion resistance.Moreover,silicone materials have process-able properties,simple forming process,good mechanical property,non-toxic and pollution-free.Therefore,silicone has been widely concerned by researchers at home and abroad.In this paper,the main research progress and application directions of carbon-silicone composite at home and abroad in recent years are reviewed.

Endoscopic dacryocystorhinostomy with bicanalicular silicone tube intubation for treating chronic dacryocystitis secondary to nasolacrimal duct stent incarceration

AIM:To investigate the feasibility of endoscopic dacryocystorhinostomy(En-DCR)with bicanalicular silicone tube intubation for treating chronic dacryocystitis secondary to nasolacrimal duct stent(NDS)incarceration.METHODS:En-DCRs were performed on 44 chronic dacryocystitis patients(46 eyes)secondary to NDS incarceration from April 2016 to October 2022.The granuloma and scar tissues were separated,and the removal of NDS incarceration was achieved during the surgery;the flap of the lacrimal sac was trimmed and anastomosed with nasal mucosal,a bicanalicular silicone tube was implanted,and lacrimal size and condition were assessed.The tube was removed 3mo after surgery.During the final follow-up of 12mo when the surgery was completed,the complications and the rates of surgical success were assessed.RESULTS:This study covered 40 patients(42 eyes).Intraoperatively,it was found that the lacrimal sac became small,and the sac wall had granulation and scar tissue attached to the incarcerated NDS in all eyes.At 12mo after surgery completed,the rates of the functional and anatomical success reached 80.95%(34/42)and 83.33%(35/42),respectively.Under the effect of intranasal ostial closure,seven eyes failed to achieve anatomical success.No serious complications(e.g.,visual impairment,sinusitis,and orbital fat prolapse)was observed.CONCLUSION:With the success rate over 80%and no serious complications,En-DCR with bicanalicular silicone tube implantation is effective in treating chronic dacryocystitis secondary to NDS incarceration.

Axial length,vitreoretinal pathology,and anterior chamber depth can predict postoperative refractive outcomes in phacovitrectomy/silicone oil removal

AIM:To evaluate the postoperative refractive prediction error(PE)and determine the factors that af fect the refractive outcomes of combined pars plana vitrectomy(PPV)or silicone oil removal(SOR)with cataract surgery.METHODS:The study is a retrospective,case-series study.Totally 301 eyes of 301 patients undergoing combined PPV/SOR with cataract surgery were enrolled.Eligible individuals were separated into four groups according to their preoperative diagnoses:silicone oil-filled eyes after PPV(group 1),epiretinal membrane(group 2),macular hole(group 3),and primary retinal detachment(RD;group 4).The variables af fecting postoperative refractive outcomes were analyzed,including age,gender,preoperative best-corrected visual acuity(BCVA),axial length(AL),keratometry average,anterior chamber depth(ACD),intraocular tamponade,and vitreoretinal pathology.The outcome measurements include the mean refractive PE and the proportions of eyes with a PE within±0.50 diopter(D)and±1.00 D.RESULTS:For all patients,the mean PE was-0.04±1.17 D,and 50.17%of patients(eyes)had a PE within±0.50 D.There was a significant difference in refractive outcomes among the four groups(P=0.028),with RD(group 4)showing the least favorable refractive outcome.In multivariate regression analysis,only AL,vitreoretinal pathology,and ACD were strongly associated with PE(all P<0.01).Univariate analysis revealed that longer eyes(AL>26 mm)and a deeper ACD were correlated with hyperopic PE,and shorter eyes(AL<26 mm)and a shallower ACD were correlated with myopic PE.CONCLUSION:RD patients have the least favorable refractive outcome.AL,vitreoretinal pathology,and ACD are strongly associated with PE in the combined surgery.These three factors affect refractive outcomes and thus can be used to predict a better postoperative refractive outcome in clinical practice.

基于In Silicon模拟消化的北极虾DPP-Ⅳ抑制肽活性分析

北极虾具有很高的营养价值,在食品领域已引起越来越多的关注。对北极虾蛋白进行In Silicon模拟消化获得寡肽,通过PeptideRanker活性评分及理化性质分析,从中筛选出具有潜在生物活性的寡肽。使用ToxinPred分析和BIOPEP-UWM生物活性预测,发现部分寡肽具有二肽基肽酶-Ⅳ(dipeptidyl peptidase-Ⅳ,DPP-Ⅳ)抑制活性,最终确定WFP(一种三肽,Trp-Phe-Pro)具有最优的DPP-Ⅳ抑制活性肽。分子对接表明,WFP和DPP-Ⅳ能够形成稳定的复合物,其结合能为-6.93 kcal/mol,进一步研究表明,WFP通过与DPP-Ⅳ S1、S2、S3三个活性口袋中的9个氨基酸残基发生相互作用而抑制其活性。本研究为阐释北极虾营养价值及生物活性肽的开发提供了理论依据。

Intraocular Silicone Oil Removed after 10 Years: A Case Report

Background: Silicone oil (SO) has been demonstrated with concrete efficacy and safety in the therapy of complex vitreoretinal diseases. SO is schemed to be cleared within several weeks or months after tamponade, but it’s inevitable for permanent or residual SO in a fraction of patients under extremely complicated clinical conditions. Here, we presented a case of silicone oil removal after 10 years, mainly to observe the disadvantages of long-term persistence. Case presentation: A 69-year-old female with pathologic myopia denied trauma history who had undergone pars plana vitrectomy (PPV), retinal reattachment, laser, and silicone oil tamponade in 2012 presented to our hospital with eye pain and headache, no light perception of her right eye for six months. The slit-lamp biomicroscopy examination for OD indicated evident conjunctival congestion, new blood vessels invasion to the limbus, foggy edema of corneal epithelium, folds of Descemet’s membrane and corneal endothelial edema. There were obvious emulsified silicone oil particles above the anterior chamber. Goldmann’s applanation tonometry test revealed the intraocular pressure was as high as 45/17mmHg. From ocular ultrasound, we saw that the vitreous cavity was filled with silicone oil in right eye;as for the left eye, it showed marked axial elongation and posterior scleral staphyloma. We were unable to obtain more information from fundus photography and macular optical coherence tomography (OCT) due to edema of the cornea. After the silicone oil was removed successfully from her vitreous cavity, although there was no improvement in the patient’s vision (no light perception), she was still satisfied with the relief from eye pain and headache benefited from the reduction of high intraocular pressure (Goldmann’s intraocular pressure decreased to 19/14mmHg). Conclusion: Patients after PPV should remove silicone oil in time to avoid corneal damage, intraocular hypertension, lens opacity and retinal damage induced by long-term silicone tamponade.

Fabrication of a flexible microwave absorber sheet based on a composite filler with fly ash as the core filled silicone rubber

A new type of composite filler was designed by a modified sol-gel method using fly ash(FA),Fe(NO_(3))_(3)·9H_(2)O,and Ni(NO_(3))_(2)·6H_(2)O as raw materials.The composite filler was a spherical core-shell structure composed of FA as the core and NiFe_(2)O_(4)as the shell.Further,the composite filler was added into the silicone rubber to fabricate the high temperature vulcanized microwave absorption materials;X-ray diffraction,fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,and scanning electron microscope confirmed that NiFe_(2)O_(4)was successfully coated on the surface of FA and formed a uniform and continuous coating layer.As expected,silicone rubber filled with the composite filler had a minimum reflection loss of-23.8 dB at 17.5 GHz with the thickness of 1.8 mm,while the effective absorption bandwidth was as high as 12 GHz.The addition of the composite filler greatly enhanced the microwave absorption properties of the system,which was resulted from multiple losses mechanism:interface polarization losses,magnetic losses,and multiple reflection losses.Also,silicone rubber filled with the composite filler exhibited excellent thermal stability,flexibility,environmental resistance,and hydrophobicity compared with traditional silicone rubber.Therefore,this work not only responds to the green chemistry to achieve efficient FA recovery,but also devises a new strategy to prepare microwave absorption materials with strong potential for civilian applications.

Vector fiber Bragg gratings accelerometer based on silicone compliant cylinder for low frequency vibration monitoring

Vector accelerometer has attracted much attention for its great application potential in underground seismic signal measurement. We propose and demonstrate a novel vector accelerometer based on the three fiber Bragg gratings(FBGs)embedded in a silicone rubber compliant cylinder at 120° distributed uniformly. The accelerometer is capable of detecting the orientation of vibration with a range of 0°–360° and the acceleration through monitoring the central wavelength shifts of three FBGs simultaneously. The experimental results show that the natural frequency of the accelerometer is about 85 Hz, and the sensitivity is 84.21 pm/g in the flat range of 20 Hz–60 Hz. Through experimental calibration, the designed accelerometer can accurately obtain vibration vector information, including vibration orientation and acceleration. In addition, the range of resonant frequency and sensitivity can be expanded by adjusting the hardness of the silicone rubber materials. Due to the characteristics of small size and orientation recognition, the accelerometer can be applied to low-frequency vibration acceleration vector measurement in narrow spaces.

Predictive factors of epiretinal membrane in complicated rhegmatogenous retinal detachment tamponaded with silicone oil

AIM:To determine the incidence and predictive factors for epiretinal membrane(ERM)formation in eyes with complicated primary rhegmatogenous retinal detachment(RRD)tamponaded with silicone oil(SO).METHODS:This retrospective case-control study included 141 consecutive patients with(51 eyes)and without(90 eyes)ERM formation after primary pars plana vitrectomy(PPV)and SO tamponade for complicated RRD.The risk factors for ERM were assessed using logistic regression analysis.RESULTS:The prevalence of postoperative ERM was 36.2%(51/141).Multivariate logistic regression analysis showed that the risk factors for ERM in SO-tamponaded eyes included preoperative proliferative vitreoretinopathy[PVR;odds ratio(OR),2.578;95%confidence interval(CI)1.580–4.205,P<0.001],preoperative choroidal detachment(OR,4.454;95%CI 1.369–14.498,P=0.013),and photocoagulation energy(OR,2.700;95%CI 1.047–6.962,P=0.040).The duration of the preoperative symptoms,intraocular SO tamponade time,giant retinal tear,preoperative vitreous hemorrhage,preoperative bestcorrected visual acuity,number of breaks,quadrants of RRD,axial length,and photocoagulation points were not predictive factors for ERM formation.CONCLUSION:Preoperative PVR,choroidal detachment,and photocoagulation energy are risk factors of ERM formation after complicated RRD repair.Better ophthalmic care as well as patient education are necessary for such patients with risk factors.

Clinical Efficacy and Safety of Foldable Capsular Vitreous Body Implant Surgery in 22 Cases of Silicone Oil-dependent Eyes

Objective This study aimed to evaluate the clinical efficacy and safety of foldable capsular vitreous body(FCVB)implant surgery in silicone oil-dependent eyes.Methods A total of 22 participants with silicone oil-dependent eyes who received treatment with FCVB implant surgery between January 2019 and June 2020 were included in this retrospective study.The intraocular pressure(IOP),best-corrected visual acuity(BCVA),demographic data,and any recorded complications were evaluated.Results The postoperative IOP(12.73±4.20 mmHg)was significantly improved(P=0.03)compared to the preoperative IOP(10.23±3.69 mmHg)(the main endpoint).There was no significant difference(P=0.33)in the final BCVA preoperation and 3rd month postoperation(the secondary endpoint).The most common postoperative complication was hyphema.Other common postoperative complications included corneal opacity,a shallow anterior chamber,and a low IOP.Conclusion FCVB implant surgery is a safe and effective method for treating silicone oil-dependent eyes;however,attention should be paid to the prevention and timely treatment of complications.

A Boron-based Adhesion Aid for Efficient Bonding of Silicone Rubber and Epoxy Resin

We improved the adhesion between silicon based insulating materials and epoxy resin composites by adding the adhesion promoter cycloborosiloxane(BSi,cyclo-1,3,3,5,7,7-hexaphenyl-1,5-diboro-3,7-disiloxane).The experimental results show that the addition of BSi in the silicone rubber(SR)system significantly increases the tensile shear strength between BSi and epoxy resin(EP),reaching 309%of the original value.On this basis,the mechanism of BSi to enhance the adhesion effect was discussed.The electron deficient B in BSi attracted the electron rich N and O in EP to enhance the chemical interaction,combined with the interfacial migration behavior in the curing process,to improve the adhesion strength.This study provides the design and synthesis ideas of adhesive aids,and a reference for further exploring the interface mechanism of epoxy resin matrix composites.

Retrolaminar migration as a complication of intraocular silicone oil injection detected on unenhanced CT

AIM:To describe the clinical and radiologic features of retrolaminar migration silicone oil(SiO)and observe the dynamic position of ventricular oil accumulation in supine and prone.METHODS:For this retrospective study,29 patients who had a history of SiO injection treatment and underwent unenhanced head computed tomography(CT)were included from January 2019 to October 2022.The patients were divided into migration-positive and negative groups.Clinical history and CT features were compared using Whitney U and Fisher’s exact tests.The dynamic position of SiO was observed within the ventricular system in supine and prone.CT images were visually assessed for SiO migration along the retrolaminar involving pathways for vision(optic nerve,chiasm,and tract)and ventricular system.RESULTS:Intraocular SiO migration was found in 5 of the 29 patients(17.24%),with SiO at the optic nerve head(n=1),optic nerve(n=4),optic chiasm(n=1),optic tract(n=1),and within lateral ventricles(n=1).The time interval between SiO injection and CT examination of migration-positive cases was significantly higher than that of migration-negative patients(22.8±16.5mo vs 13.1±2.6mo,P<0.001).The hyperdense lesion located in the frontal horns of the right lateral ventricle migrated to the fourth ventricle when changing the position from supine to prone.CONCLUSION:Although SiO retrolaminar migration is unusual,the clinician and radiologist should be aware of migration routes.The supine combined with prone examination is the first-choice method to confirm the presence of SiO in the ventricular system.

Microstructure evolution and strengthening mechanism of high -performance powder metallurgy TA15 titanium alloy by hot rolling

Hot deformation of sintered billets by powder metallurgy(PM)is an effective preparation technique for titanium alloys,which is more significant for high-alloying alloys.In this study,Ti–6.5Al–2Zr–Mo–V(TA15)titanium alloy plates were prepared by cold press-ing sintering combined with high-temperature hot rolling.The microstructure and mechanical properties under different process paramet-ers were investigated.Optical microscope,electron backscatter diffraction,and others were applied to characterize the microstructure evolution and mechanical properties strengthening mechanism.The results showed that the chemical compositions were uniformly dif-fused without segregation during sintering,and the closing of the matrix craters was accelerated by increasing the sintering temperature.The block was hot rolled at 1200℃ with an 80%reduction under only two passes without annealing.The strength and elongation of the plate at 20–25℃ after solution and aging were 1247 MPa and 14.0%,respectively,which were increased by 24.5%and 40.0%,respect-ively,compared with the as-sintered alloy at 1300℃.The microstructure was significantly refined by continuous dynamic recrystalliza-tion,which was completed by the rotation and dislocation absorption of the substructure surrounded by low-angle grain boundaries.After hot rolling combined with heat treatment,the strength and plasticity of PM-TA15 were significantly improved,which resulted from the dense,uniform,and fine recrystallization structure and the synergistic effect of multiple slip systems.

Shock Raman spectra and structural transformation of powdered TKX-50 by the plate impact experiments combined with real-time Raman detection

As an energetic material of great interest,the work capacity of dihydroxylammonium 5,5’-bistetrazole-1,1’-diolate(TKX-50)has been questioned recently.Although some research groups have explored the reasons for the low working ability of TKX-50,the plane impact experiment on powdered TKX-50 is obviously closer to the practical application,and the conclusions based on this are more guiding.Hence,we performed shock Hugoniot measurements of powdered TKX-50 between 5.65 and 16.29 GPa.The plane impact experiments of powdered TKX-50 were carried out and the shocked Raman spectra were collected.By Raman spectroscopy analysis,a new peak of powdered TKX-50 was found between19.47 GPa and 24.96 GPa,which may be caused by decomposition/phase transition and was related with the low work capacity.

From 0D to 3D:Hierarchical structured high-performance free-standing silicon anodes based on binder-induced topological network architecture

Free-standing silicon anodes with high proportion of active materials have aroused great attention;however,the mechanical stability and electrochemical performance are severely suppressed.Herein,to resolve the appeal issues,a free-standing anode with a"corrugated paper"shape on micro-scale and a topological crosslinking network on the submicron and nano-scale is designed.Essentially,an integrated three-dimensional electrode structure is constructed based on robust carbon nanotubes network with firmly anchored SiNPs via forming interlocking junctions.In which,the hierarchical interlocking structure is achieved by directional induction of the binder,which ensures well integration during cycling so that significantly enhances mechanical stability as well as electronic and ionic conductivity of electrodes.Benefiting from it,this anode exhibits outsta nding performance under harsh service conditions including high Si loading,ultrahigh areal capacity(33.2 mA h cm^(-2)),and high/low temperatures(-15-60℃),which significantly extends its practical prospect.Furthermore,the optimization mechanism of this electrode is explored to verify the crack-healing and structure-integration maintaining along cycling via a unique self-stabilization process.Thus,from both the fundamental and engineering views,this strategy offers a promising path to produce high-performance free-standing electrodes for flexible device applications especially facing volume effect challenges.

Lactose-free milk powder can effectively relieve diarrhea symptoms in weaning SD rats and children

Diarrhea has become the leading cause of illness and death among infants and young children in developing countries.Clinically,patients with diarrhea showed damaged intestinal epithelial villi,usually accompanied by lactase deficiency.In this study,we evaluated the therapeutic effects of lactose-free milk powder on rats and children with diarrhea.Antibiotic-associated diarrhea(AAD)model was established by gavage with antibiotic mixture in SD rats,followed by administration of milk powder containing lactose or not.The results showed that lactose-free milk powder ameliorated A AD-related diarrhea symptoms,and accelerated the recovery from diarrhea.And 16S sequencing results indicated lactose-free milk powder contributed to increase theα-andβ-diversity of intestinal flora,and restore the intestinal microbiota disorder.In conclusion,our data demonstrate that lactose-free milk powder could alleviate diarrhea by restoring gut microbiota and intestinal barrier function.

Integrated high-performance and accurate shaping technology of low-cost powder metallurgy titanium alloys: A comprehensive review

The practical engineering applications of powder metallurgy (PM) Ti alloys produced through cold compaction and pressure-less sintering are impeded by poor sintering densification, embrittlement caused by excessive O impurities, and severe sintering deforma-tion resulting from the use of heterogeneous powder mixtures. This review presents a summary of our previous work on addressing the above challenges. Initially, we proposed a novel strategy using reaction-induced liquid phases to enhance sintering densification. Near- complete density (relative density exceeding 99%) was achieved by applying the above strategy and newly developed sintering aids. By focusing on the O-induced embrittlement issue, we determined the onset dissolution temperature of oxide films in the Ti matrix. On the basis of this finding, we established a design criterion for effective O scavengers that require reaction with oxide films before their dissol-ution. Consequently, a ductile PM Ti alloy was successfully obtained by introducing 0.3wt% NdB6 as the O scavenger. Lastly, a powder- coating strategy was adopted to address the sintering deformation issue. The ultrafine size and shell-like distribution characteristics of coating particles ensured rapid dissolution and homogeneity in the Ti matrix, thereby facilitating linear shrinkage during sintering. As a result, geometrically complex Ti alloy parts with high dimensional accuracy were fabricated by using the coated powder. Our fundament-al findings and related technical achievements enabled the development of an integrated production technology for the high-performance and accurate shaping of low-cost PM Ti alloys. Additionally, the primary engineering applications and progress in the industrialization practice of our developed technology are introduced in this review.