Metal Needle Research Articles

On the absorption properties of metallic needles

ABSTRACT Needle-like metallic particles have been suggested to explain a wide variety of astrophysical phenomena, ranging from the mid-infrared interstellar extinction to the thermalization of starlight to generate the cosmic microwave background. These suggestions rely on the amplitude and the wavelength dependence of the absorption cross-sections of metallic needles. On the absence of an exact solution to the absorption properties of metallic needles, their absorption cross-sections are often derived from the antenna approximation. However, it is shown here that the antenna approximation is not an appropriate representation, since it violates the Kramers–Kronig relation. Stimulated by the recent discovery of iron whiskers in asteroid Itokawa and graphite whiskers in carbonaceous chondrites, we call for rigorous calculations of the absorption cross-sections of metallic needle-like particles, presumably with the discrete dipole approximation. We also call for experimental studies of the formation and growth mechanisms of metallic needle-like particles as well as experimental measurements of the absorption cross-sections of metallic needles of various aspect ratios over a wide wavelength range to bound theoretical calculations.

Minimally invasive and inexpensive percutaneous abscess drainage using an indwelling needle cannula

PurposeAbscess is still a formidable disease and requires adequate drainage. Moreover, drainage in the head and neck area needs cosmetic care, especially in the pediatric population. In this report, we introduce our method of percutaneous abscess drainage using an indwelling needle cannula.Patients and methodsTen pediatric and five adult patients with cervical and/or facial abscess treated with this drainage method were retrospectively reviewed. Using an indwelling needle cannula (18-14 G Surflow®, Terumo, Tokyo, Japan), abscesses were penetrated under ultrasonic examination. Once purulent retention was identified, the inner metal needle was removed and the outer elastic needle was left and fixed. The outer needle was connected to the tube for continuous suction drainage for large abscess.ResultsThe primary diseases of these abscesses were cervical abscess of dental origin (5), purulent lymphadenitis (3), pyriform sinus fistula (2) and subperiosteal abscess due to mastoiditis (2), circumorbital cellulitis (1), infection of Warthin's tumor (1), and unknown origin (1). The median (range) duration of drainage was 4 days (3–9 days). Abscesses were successfully treated, and no patients required additional incision for abscess drainage. No apparent scars after drainage were observed.ConclusionThis technique resembles the usual venous placement of an indwelling needle cannula and is thought to be familiar to physicians. Although simple and inexpensive, this drainage is safe, effective, and minimally invasive for the treatment of abscess.

A study on the management of needle-stick and sharps injuries based on total quality management in a tertiary hospital in western China.

Based on the concept of total quality management, the practice of managing needle-stick and sharps injuries was analyzed to improve nursing quality. Using total quality management, an improvement plan was completed. Standard operating procedures for infusion therapy and monitoring of the circulatory system were made to reduce the utilization of winged metal needles and the frequency of needle-stick injuries. From 2015 to 2018, four cross-sectional surveys were conducted on the use of winged metal needles, peripheral intravenous catheters, central venous catheters, peripherally inserted central catheters, and implantable venous access ports and the status of needle-stick and sharps injuries in our hospital during the 4 years. Four cross-sectional surveys showed that the percentage of winged metal needle utilization decreased significantly from 13% to 0.5%, and that of peripheral intravenous catheters increased from 77% to 87%. Zero tolerance of winged metal needles increased from 33 to 60 nursing units, an improvement rate of 81.82%. The number of needle-stick injuries decreased from 71 to 21, a decrease of 70.42%. Needle-stick injuries occurred mainly during waste disposal (34.71%) and needle withdrawal (18.18%) and when recapping needles (9.92%). Based on total quality management, the implementation of zero tolerance of winged metal needles is much better. The use of winged metal needles and the incidence of needle-stick injuries are reduced. Total quality management is of great clinical value in preventing needle-stick injuries.

Foreign bodies in orthopaedic emergency: two-year study at Barzulla hospital GMC Srinager

This study was carried out at Government hospital for bone and joint surgery Barzulla at GMC Srinager from March 2017 – March 2019. All the patients who presented with soft tissue, upper and lower extremity foreign bodies in emergency department were included in the study. Patients with foreign bodies who were referred from peripheral hospitals and associated surgical department of the college were also included in the study. A total of 52 foreign body patients were included in the study period. All except two foreign bodies were removed in the emergency operation theatre of the department. Out of 52 patients 36 were females. The mean age was 23 years and the most common foreign body removed in the study period was metallic needle followed by piece of wood.

Study on the combined characteristics of UHF and optical signals induced by partial discharge at spacer surface in GIS

In this study, to improve the sensitivity and accuracy of the detection of surface partial discharge (PD) in gas insulation switchgears (GISs), a combination of ultra-high frequency (UHF) and optical methods is proposed based on an integrated sensor. The PD triggered by a fixed metal needle defect attached to the spacer is detected from PD inception to flashover in a real GIS. The characteristics of UHF and optical signals under different applied voltages are compared and analysed in terms of PD waveform, Phase Resolved Partial Discharge (PRPD) pattern, PD count and amplitude. The results show that the surface discharge process can be precisely divided into three stages according to the combined characteristics of the UHF and optical signals. The comparison of the two detection methods shows that the optical method can detect the weak avalanche PD under low voltage while UHF cannot, so it can detect more PDs than UHF method in an AC cycle. In addition, with the deterioration of solid insulation material, the amplitude of the optical signal increases significantly while the amplitude of the UHF signal only increases slightly.

Modeling of active shimming of metallic needles for interventional MRI.

Artifacts caused by large magnetic susceptibility differences between metallic needles and tissue are a persistent problem in many interventional MRI applications. The signal void caused by the needle can hide procedure targets and prevent accurate image-based monitoring. In this paper, a solution to this problemis presented in the form of an active shim insert inspired from degaussing coils used in naval vessels, that isdesignedto correct the field disturbance (ΔB0 ) caused by the needle. The ΔB0 induced by a 10 gauge hollow single-beveled titanium needle at 3T is modeled in different orientations. A set of 63 orthogonal coil pairs with unique tip paths are evaluated for shimming performance, and an optimal coil pair is chosen. Shimming performance and current demands are evaluated over a range of needle orientations. Robust correction of the titanium needle induced ΔB0 is predicted using a flat no-loop coil combined with an orthogonal 1½ turn loop coil angled at the bevel angle for most orientations, with currents well below 1 amp per coil. Reductions in ΔB0 standard deviations with shimming ranged from ~49% to ~10% depending on needle orientation, with performance worsening as the needle is aligned more along B0 . Simulations predict that it is possible to minimize metallic probe induced ΔB0 and signal losses using externally supplied direct current shim coil inserts in arbitrary orientations for potential benefits in many interventional MRI applications.

The Efficiency and Safety of Endoscopic Treatment on Kidney-Transplanted Patients With Symptomatic Vesicoureteral Reflux in Native and Transplanted Renal Units

ObjectivesTo evaluate the outcome of endoscopic treatment of symptomatic vesicoureteral reflux (VUR) in patients with VUR in both transplanted and native renal units. Material and MethodsBetween January 2014 and December 2019, 23 transplanted patients with symptomatic VUR with reflux in both transplanted and native kidney were included in the study. All patients were patients with a history of kidney failure due to reflux nephropathy. A voiding cystourethrography was performed after at least 1 episode of acute glomerulo pyelonephritis or deterioration of the graft function. All patients underwent a urine culture and an ultrasonic evaluation preoperatively. A dextranomer/hyaluronic acid bulking agent was injected via endoscope by a rigid metal needle around a double J stent. Clinical success was defined as absent of febrile urinary tract infection during the follow-up period. ResultsThe procedure was applied in 52 effected renal units; of these, 27 were transplanted kidneys, and 25 were native kidneys. Overall clinical success was achieved in 69.6% (N = 16) of patients. The success rate after the first procedure was 52.2% (N = 12), whereas 17.3% (N = 4) achieved success after the second treatment. No intraoperative complications occurred throughout the endoscopic procedure. Minor postoperative complications included 2 (10%) cases of self-limiting episodes of hematuria that did not require intervention. ConclusionEndoscopic treatment of symptomatic VUR for both transplanted ureter and native ureter is a safe treatment in most of the patients. Therefore, endoscopic ureteral injection is a treatment modality with low morbidity that should be preferred to open surgery as first-line treatment in this subgroup of patients.

Effects of Flexible Induction Coil Pitch on the Heating Performance of Thermotherapy Needles

This article presents a newly developed flexible laminated copper (FLC) coil for electromagnetic thermotherapy that has several advantages over traditional hard copper coils. We study the effect of pitch (the distance between coil turns) on the heating performance of the proposed FLC coil. The flexible coil can be wound into different shapes for various purposes. However, the output power of the heating system can be substantiality affected by the coil inductance. This study is aimed at reducing coil inductance by changing the original flexible coil diameter and pitch in order to enhance the output power of a high-frequency machine, improve treatment, and meet the actual heating requirements. The results of the experiments show that the temperature is six times better when using the flexible coil compared with when using the traditional hard copper coil, where adjusting the coil pitch can increase the needle temperature by a maximum of 48.3 °C in pork liver tissue. In addition, this study simulates the distribution of the magnetic field of the flexible coil via a finite element analysis and explores the coil design and heating effect of metal needle heating and liver tissue ablation. The improved features of this proposed method are threefold: 1) the flexible coil can be used to treat different zones of the human body; 2) the flexible coil exhibits better heating performance than a hard copper coil; and 3) the coil inductance is lowered, and the power is improved, which, in turn, leads to better treatment and meets the actual heating requirements.

Effect of frequency and applied voltage of an atmospheric-pressure dielectric-barrier discharge on breakdown and hydroxyl-radical generation with a liquid electrode

This work examines the effect of the frequency and peak applied voltage on hydroxyl-radical generation in a dielectric-barrier plasma discharge between a metallic needle electrode and one electrode covered with dielectric. The authors examine a system that can expose up to 96 liquid samples in an automated fashion without human intervention beyond setting the initial software configuration. Then, hydroxyl-radical concentration, measured through coumarin fluorescence, was measured for 5 s plasma exposures generated under different high-voltage conditions with frequencies from 2 to 16 kHz and amplitudes from 4 to 9 kV. Their results show that an increase in frequency and/or applied voltage, within the range prescribed above and the limits of the high-voltage power supply, can yield up to a 150% increase in fluorescence with an equivalent hydroxyl-radical increase. Applications using typical previous methods, such as the Fenton Reaction, are limited in that they continuously generate hydroxyl radicals over millisecond and longer intervals. These results establish the electrical parameters that can now be applied to polymers, like proteins, which show three dimensional structures that are flexible and fluctuate on a microsecond and nanosecond time scale, with hydroxyl-radical generation on this time scale using this device. Additionally, plasma exposures may be optimized for a great variety of proteins, devices and techniques, where hydroxyl-radical generation is of utmost importance, reducing exposure time and potential subjection of samples to harmful side effects.

Considerations in Access Cannulation: Traditional and Evolving Approaches.

Needle cannulation of hemodialysis access is the soft underbelly of hemodialysis access care that has remained unchanged for a long time. Cannulation error results in complications such as infiltration, hematoma, subsequent revision procedures, and potential loss of hard-earned access. The "best" cannulation method is contingent upon access type and characteristics along with local expertise. The rope ladder technique of cannulation, characterized by successive rotation of puncture sites with each hemodialysis session, permits sufficient time for healing of prior cannulation sites, and reduction in complications such as bleeding, infection, and aneurysm development. A steeper needle angle, higher blood flow rates, and deep needle tip can lead to wall stress on the posterior wall and up to 10cm from the needle cannulation site. Plastic cannulas provide a viable alternative to metallic needles; they have lower complications and a favorable cost-benefit ratio. There is lack of evidence to support an optimal arterial needle direction configuration. Needle injury may promote intimal thickening, but its effect on access outcomes is currently unknown. Percutaneous creation of arteriovenous fistula presents new challenges in dialysis access cannulation. Point-of-care ultrasound-guided cannulation will likely lead to a paradigm shift in access cannulation. Novel care delivery using cannulation stations is a promising development.

Acupuncture or auricular electro-acupuncture as adjuncts to lifestyle interventions for weight management in PCOS: protocol for a randomised controlled feasibility study

BackgroundPolycystic ovary syndrome (PCOS) is a prevalent women’s health condition with reproductive, metabolic, and psychological manifestations. Weight loss can improve these symptoms and is a key goal; however, many women find this difficult to achieve. Acupuncture is a Chinese medical treatment that involves insertion of very fine metal needles into specific areas of the body and has been shown to be efficacious for weight loss in non-PCOS populations. However, few studies have been conducted in women with PCOS. A variant of acupuncture, auricular electro-acupuncture (AEA), may have beneficial effects on sympathetic tone, which is associated with insulin resistance, obesity and PCOS.MethodsThis prospective three-arm open label parallel randomised controlled trial will assess feasibility and acceptability of acupuncture and/or AEA for weight loss in women with PCOS. We will enrol 39 women from the community aged between 18 and 45 years, with physician diagnosis of PCOS according to the Rotterdam criteria: body mass index (BMI) between 25 and 40 kg/m2. Women will be randomly allocated to receive one of three treatments for 12 weeks duration: body electro-acupuncture + lifestyle interventions, AEA + lifestyle interventions, or lifestyle interventions alone. The lifestyle intervention in this study is telephone-based health coaching (between 4 and 13 phone calls, depending on individual need), provided by the Get Healthy Service. Primary outcomes of the study are feasibility and acceptability of trial methods as determined by recruitment and retention rates, adherence, acceptability, credibility, and safety. Secondary outcomes include anthropometric (body weight, BMI, waist and hip circumference), metabolic (glucose tolerance and insulin sensitivity obtained from a 2-h 75 g oral glucose tolerance test with area under the curve insulin calculated using the trapezoid rule), reproductive (androgen levels, menstrual cyclicity, clinical hyperandrogenism using the Ferriman-Gallwey scoring system), autonomic (heart rate variability, blood pressure), lifestyle (physical activity levels, diet quality, weight self-efficacy), quality of life, and psychological (depression and anxiety symptoms, internal health locus of control).DiscussionThis study addresses the feasibility and acceptability of novel interventions to treat overweight/obesity in PCOS. Study findings have the potential to generate a new understanding of the role of acupuncture and auricular acupuncture in weight management.Trial registrationAustralian New Zealand Clinical Trial Registry, 8/6/18 ACTRN12618000975291

Suppressing and controlling electrostatic charge in micropipetting

Commonly used liquids have a powerful effect on producing electrostatic charges, from laboratory routines to industry processing and everyday activities. In many situations, electrostatic charges are not desirable, mostly in the presence of flammable liquids or for electronic devices that are susceptible to electrostatic discharge (ESD). Recently, liquid water was successfully allocated in the triboelectric series and it was shown that it can acquire great amounts of charge when flowing through different materials or even by a simple micropipetting. Here, we have developed a simple but robust protocol to suppress and control electrostatic charges during the pipetting of water, common alcohols and solutions. Using glass containers instead of plastic ones, charge is highly suppressed and its sign and magnitude can be controlled with external electrical fields. Finally, drops arising from a micropipette ended in a grounded metallic needle have roughly zero net charge, regardless the presence of external electrical fields. This protocol faces a very challenging problem of electricity formation while handling common liquids and it could be helpful to avoid electrostatic charge in many systems.

COMPARATIVE STUDY OF ELECTRICAL AND PHYSICAL PARAMETERS OF GLOW DISCHARGE UNDER WATER SOLUTIONS OF ANIONIC AND CATIONIC SURFACTANTS

The results of experimental study of the electrical and physical parameter of the gas discharge in air under the solutions of the two types of surfactants are given. The discharge was ignited between metal needle anode and liquid cathode. As the cathode the solutions of anionic surfactant C12H25SO4Na (SLS) and cationic surfactant C12H46ClN, (AOTC) were used. In the concentration range of 5·10-3-10 g/L and discharge current range of 20-100 mA the phenomenology of discharge was studied, the current densities and inputted power, cathode voltage drops, vibrational temperatures of N2(C3Πu), gas temperatures were obtained and reduced electric field strength was calculated. It was show that increase of the SLS concentration leads to the change in the discharge color due to transfer of Na atoms from liquid to the gas phase. In the same time there are no any new emission lines or band for the AOTC solutions were obtained. It was established that for cationic surfactants the cathode voltage drop is lower than for anionic surfactant. The gas temperatures and vibrational temperatures don’t depend on solution type. Reduced electric field is in the range of 10-15 Td and the increase of the concentration leads to decrease of the E/N. The increase of the discharge current results in the growth of reduced electric field.

Numerical Simulation and Experimental Validation of Liquid Metal Droplet Formation in a Co-Flowing Capillary Microfluidic Device.

A two-phase flow axisymmetric numerical model was proposed to understand liquid metal droplet formation in a co-flowing capillary microfluidics device based on a phase field model. The droplet detachment processes were observed in the experiment and are in good agreement with the simulation method. The effects of the viscosities and flowrates of the continuous phase fluid, interfacial tension as well as the wetting property of the metallic needle against the bulk liquid metal on the droplet formation and production rate were numerically investigated. It was found that the droplet diameter decreased with the increment of the viscosities and flowrates of the outer phase carrier fluid. The dispersed phase fluid with high interfacial tension tended to prolong the time for equilibrium between the viscous drag force and interfacial tension on the liquid–liquid fluid surface, delaying the droplet to be pinched off from the capillary orifice and causing large droplet diameter. Finally, the wetting performance of the metallic needle against the liquid metal was explored. The result indicate that the droplet diameter became less dependent on the contact angle while the size distribution of the liquid metal droplet was affected by their wetting performance. A more hydrophilic wetting performance were expected to prepare liquid metal droplet with more monodispersity. The numerical model and simulation results provide the feasibility of predicting the droplet formation with a high surface tension in a glass capillary microfluidic device.

Seasteading

Seasteading Tana Jean Welch (bio) I E Mare Libertas Seasteading seeks to move human communitiesout into the vast expanse of sea smothering the globe. The oceans contain99 percent of the living space on earth and we want that space. II The Final Frontier Her lips move and we know what she is saying the woman in the hot pink skirt suit, her new blonde hair hired to boost the seasteading movement: "Floating cities are the next frontier," she says and senses the hostof this cable news show is about to interrupt, about to say something intended to highlight her gender, so she rushes the next line: [End Page 176] "All the surface area on this planet is occupied." She is good at her job so his smug jowls rest while she speaksabout the need for space, more space to experiment with new ways of living. But then the host reaches across the table, grabssqueezes her hand in one oil slick gesture Tell me dear,who is allowed to live on this floating city? her lipstick flakes as the camera zooms in on her face and we can tell it wasn't the pale handof the host, but his question that woke in her eyesan animal kingdom of jealousy as she fears both her own exclusion and the inclusion of all others in parachutesdescending upon the high seas. [End Page 177] III Democracy "...leads to unrest, runaway spending, and a tyrannical government." —Frank Karsten, Beyond Democracy IV Entrepreneurial Opportunities on the sea they might sell fishto passers-by on boats or they might sell fishto other like-minded people afloat on the floating city the word selfish is seventeenth-centuryPresbyterian, first usedin reference to events of the year 1641 which could be any numberof events, including but not limited tothe Iroquois declaring war against New France,the Dutch seizure of Malacca (or the Dutch capture of Angola),or the Irish Rebellion in Ulster self-ful, self-ended, self-seeking:synonyms used during the Early Modern era how else to sell fish? freeze, pack, ship (no need to heed the regulations) string a metal needle through the eyes, brine hang dry and vacuum pack [End Page 178] or they might not sell it at allbut fry it on a Friday, swallow as much as they can and bury the rest at sea V Recruiting Please complete this survey: Why would you choose to live on a seastead? (click all that apply) □ Opportunity to experiment with new governance □ Preference for small communities □ Solitude □ Love of the sea □ Desire to pioneer a new way of life □ Commercial advantages of conducting an offshore enterprise Would you want to operate a business from the seastead? If yes, what kind of business would you like to operate? Do you own more than one home? What is the total value of your real estate assets? How many days a year do you spend on vacation? Do you own a timeshare? If you own a timeshare, how much do you pay for it annually? [End Page 179] VI Ephemerisle Ephemerisle is a floating celebration of community and seasteading. There are no tickets, no central organizers, and no rangers to keep you safe. Ephemerisle prepares usfor our future world through five days of floating on the Sacramento River Delta. You must practice radical self-reliance. You must build a boat. There is limited space. There are no rangersto keep you safe. You are free to do what you want.You must conform to the island commodore's rules. There are no rangers to keep you safe. You are free to do what you want. You can sleep in the nude.You can eat all of your food.You can carve trees in your calves with a switchblade or machete. You can horde life jackets and flares.You can snort several lines of pure white Prague. You can keep your drawbridge raised. You can hoist a flagdepicting buckteeth biting watermelon, but there are no rangers to keep you safe.You can dress your feet in pink FiveFingers.You can have ten wives [End...

Charge-Simulation-Based Electric Field Analysis and Electrical Tree Propagation Model with Defects in 10 kV XLPE Cable Joint

The most severe partial discharges and main insulation failures of 10 kV cross-linked polyethylene cables occur at the joint due to defects caused by various factors during the manufacturing and installation processes. The electric field distortion is analyzed as the indicator by the charge simulation method to identify four typical defects (air void, water film, metal debris, and metal needle). This charge simulation method is combined with random walk theory to describe the stochastic process of electrical tree growth around the defects with an analysis of the charge accumulation process. The results illustrate that the electrical trees around the metal debris and needle are more likely to approach the cable core and cause main insulation failure compared with other types of the defects because the vertical field vector to the cable core is significantly larger than the field vectors to other directions during the tree propagation process with conductive defects. The electric field was measured around the cable joint surface and compared with the simulation results to validate the calculation model and the measurement method. The air void and water film defects are difficult to detect when their sizes are less than 5 mm3 because the field distortions caused by the air void and water film are relatively small and might be concealed by interference. The proposed electric field analysis focuses on the electric field distortion in the cable joint, which is the original cause of the insulation material breakdown. This method identifies the defect and predicts the electrical tree growth in the cable joint simultaneously. It requires no directly attached or embedded sensors to impact the cable joint structure and maintains the power transmission during the detection process.

The impact of air gaps between needle and polymer on electrical treeing in needle-plane samples

Electrical trees are widely grown in laboratories from metallic needle electrodes to enable the degradation process to proceed rapidly at voltages of ∼10 kV AC. Here it is shown that cone-shaped air gaps may form at a needle tip, even when they are not visible optically. Using X-ray imaging techniques, samples with and without air gaps up to 55 μm long have been characterized. The presence of air gaps led to partial discharge (PD) patterns resembling void-discharges. Prior to tree initiation, discharge characteristics evolved with increased voltage increments and increased phase lag behind the applied voltage. These changes to PD characteristics reflect a change in the physical state of the air gap. Although samples with air gaps generally initiated trees quicker than those with no gap, PD activities did not appear to play a decisive role in tree initiation times. However, initial voids were found to have major impact on the subsequent tree growth. In samples with persistent pre-tree air-gap PDs, trees grew larger branchy structures with higher PD magnitudes. In addition, the PDs became more asymmetric between positive and negative half-cycles than occurred in samples with no air gaps. It is shown that understanding the interface between the needle and polymer at a micron scale is critical to interpretation of laboratory tree growth experiments.

Boron-containing intermetallic compounds in Mn–Cu–Al/430 stainless steel brazed joints formed under a borate brazing flux

Intermetallic compounds (IMCs) distributed at the interface reduce the bonding strength of Mn–Cu–Al alloy/430 stainless steel (430SS) brazed joints. Here, we investigated the formation mechanism of IMCs to improve the reliability of brazed joints. Mn–Cu–Al high-damping alloy and 430SS were induction-brazed assisted by Cu–34Mn–6Ni–6Sn filler metal and borate brazing flux. Shapeless IMCs were observed to be distributed in chains at the joint interfaces. Moreover, shear cracks propagated along the IMC chains. The IMCs were determined to be (Fe, Cr, Mn)2B; elemental B could only come from the brazing flux according to the materials used for brazing. We propose that IMC formation consists of four stages: (i) substrate dissolution and filler metal diffusion, (ii) B2O3 reduction, (iii) IMC nucleation, and (iv) needle growth and chain distribution of IMC.

Nasolacrimal stent with shape memory as an advanced alternative to silicone products

Epiphora is the overflow of tears typically caused by obstruction or occlusion of the nasolacrimal duct. More attention is required to address this global health issue owing to the increase in air pollution. Implantation of a silicone stent is the preferred treatment for epiphora; however, introducing a silicone stent into a narrow duct with complex geometry is challenging as it requires guidance by a sharp metal needle. Additionally, silicone can cause adverse reactions such as biofilm formation and tear flow resistance due to its extreme hydrophobicity. To overcome these problems, in this study we developed a new type of biocompatible shape memory polymer (SMP) stent with elasticity capacity for self-expansion. First, SMPs in the form of x%poly(ε-caprolactone)-co–y%poly(glycidyl methacrylate) (x%PCL–y%PGMA) were synthesized via ring opening polymerization by varying the molar ratio of PCL (x%) and PGMA (y%). Second, the shape memory and mechanical properties were tuned by controlling the crosslinking degree and concentration of x%PCL–y%PGMA solution to produce a test type of SMP stent. Lastly, this 94%PCL–06%PGMA stent exhibited more standout critical functions in a series of in vitro and in vivo experiments such as a cell growth-supporting level of biocompatibility with nasal epithelial cells without significant inflammatory responses, better resistance to biofilm formation, and more efficient capacity to drain tear than the silicone control. Overall, 94%PCL–06%PGMA can be suggested as a superior alternative to the currently used materials for nasolacrimal stents. Statement of significanceSilicone intubation (stenting) has been widely used to treat nasolacrimal duct obstruction, however, it can cause adverse clinical effects such as bacterial infection; presents procedural challenges because of the curved nasolacrimal duct structure; and shows poor drainage efficiency stemming from the highly hydrophobic nature of silicone. In this work, we describe an innovative shape memory polymer (SMP) as a superior alternative to conventional silicone-based materials for nasolacrimal duct intubation. We demonstrate the clear advantages of the SMP over conventional silicone, including a much higher drainage capacity and superior resistance to bacterial infection.

P2.17-08 Ethanol Release Heat-Generating Polymer for Focal Therapy of Small Lung Cancers Under Open MRI

Recently, the lung cancer lesions of small GGO lesions are increasingly found. Such an elderly person who found a small cancer lesion reveals low durability for surgery and sometimes has many medical complications around chronic diseases. therapy of micro lung cancers under open MRI and developed medical devices. We have synthesized low viscosity silicon material which absorb a trace amount of water, generates heats and indurate in a few minutes. We have adjusted the concentration of titanium catalyzer, and a fine image can be visualized under CT imaging equipment and 0.3T open MRI. In animal experiments, rat lungs are divided in 10-micron unit CT imaging, the indurated conditions of thermosetting resin in the lungs was analyzed as 3D DICOM image data and 0.3T MRI DICOM images of Hitachi Corporation. We have developed non-artifact metallic needle as a biopsy needle under open MRI circumstance. It was confirmed that the indurated resin was hardened three-dimensionally without cracks, the surrounding cells were damaged, the resin can be detected with CT. The micro resin can be detected with 0.3T Open MRI. We have succeeded in synthesizing “Ethanol Release Heat-Generating Polymer” for focal therapy of micro lung cancers and archiving non-artifact medical devises under MRI. The idea of this research is Japanese patent JP6447858. This work was PCT patent pending JP2017/025044 in US and China and supported by JSPS KAKENHI Grant Number JP15K15517 and 18H05377.