Injection Device Research Articles

One stone two birds: Simultaneous realization of partial oxidation of methane to syngas and N2 purification via robust ceramic oxygen-permeable membrane reactors

To obtain liquid fuel and high purity N2, extensive energy is consumed in converting methane to syngas (H2 + CO) and in separating N2 from air. Conventional studies were mainly focused on the partial oxidation of methane (POM) to syngas instead of the N2 purification. Here, we report a win-win scheme of POM to syngas and N2 purification using a high performance ceramic hollow membrane reactor. The mixed ionic and electronic conducting doped La0.8Ca0.2Fe0.95Ag0.05O3−δ (LCF-Ag) powder enduring harsh environment at high temperatures was synthesized and prepared into hollow fibre membranes. By using a self-designed injection device, the high-efficiency catalyst (Ni/LaNiO3/γ-Al2O3) was uniformly anchored on the inner surface of the hollow fiber along the whole length to guarantee the ideal reaction rate to achieve the desirable reaction efficiency, product selectivity and nitrogen purity. At 900 ℃, 99% methane conversion, 93% CO selectivity and syngas with suitable ratio of H2/CO were obtained by using both membrane modules containing one single or three hollow fiber membranes. Meanwhile, N2 with purity over 99.9% can be separated from gas mixture (synthetic air) due to the removal of oxygen which was consumed by POM. These results suggest that POM to syngas and N2 purification can be achieved using a high-performance ceramic hollow fiber membrane reactor toward green and energy-saving technology. This is a promising win-win scheme of catalytic reaction combining with gas separation.

Facile production of three-dimensional chitosan fiber embedded with zinc oxide as recoverable photocatalyst for organic dye degradation

Herein we report on a facile and green strategy for continuous production of chitosan-zinc oxide fibers and then compare their photodegradation performance against three organic dyes (i.e., methylene blue (MB), methyl orange (MO) and Rhodamine B, respectively) under different lights. Chitosan-zinc hydrogel fibers (CS/Zn) with different zinc loadings are obtained by direct mixing of chitosan and zinc acetate solutions using a double-syringe injection device. The as-prepared CS/Zn fibers are then immersed into glutaraldehyde (GA) and sodium hydroxide solutions, respectively, and dried at T = 50 °C. The resultant CS/ZnO/GA fibers of ca. 617 μm in diameter are characterized using X-ray diffraction (XRD), thermogravimetric analysis and field emission scanning electron microscope (FE-SEM). XRD and FE-SEM data confirm that the CS/ZnO/GA fibers consist of a large amount of hexagonal wurtzite ZnO nanorods up to 550 nm in length, and exhibit three-dimensional interconnected macroporous architecture. Photodegradation results clearly show that the CS/ZnO/GA fibers are effective for the removal of organic dyes upon UV irradiation and can be easily recovered and reused for at least 6 consecutive cycles. Unlike most reported CS/ZnO nanocomposites, the current CS/ZnO/GA fiber shows a higher adsorption of cationic MB rather than anionic MO, the mechanism of which is proposed.

C band microwave damage characteristics of pseudomorphic high electron mobility transistor* *Project supported by the Foundation Enhancement Plan and the National Natural Science Foundation of China (Grant No. 61974116).

The damage effect characteristics of GaAs pseudomorphic high electron mobility transistor (pHEMT) under the irradiation of C band high-power microwave (HPM) is investigated in this paper. Based on the theoretical analysis, the thermoelectric coupling model is established, and the key damage parameters of the device under typical pulse conditions are predicted, including the damage location, damage power, etc. By the injection effect test and device microanatomy analysis through using scanning electron microscope (SEM) and energy dispersive spectrometer (EDS), it is concluded that the gate metal in the first stage of the device is the vulnerable to HPM damage, especially the side below the gate near the source. The damage power in the injection test is about 40 dBm and in good agreement with the simulation result. This work has a certain reference value for microwave damage assessment of pHEMT.

Assessment and Impact of Var Injection Devices on System Parameters

In this research work, analysis and effect of reactive power injection at different voltage level are carried out. The 39-bus test network modeled in mipower software is a part of Rajasthan power system attached with North Regional Grid of Indian Power system synchronized at 765 kV voltage level. The present problem of high load and mismanagement in providing required compensation is addressed in this paper by simulation case study. Reactive power drawl from the components end is judged and analyzed by placing fictious generator at respective voltage level. State power system area is wide, having a hierarchy voltage level varying from 765 to 33 kV, but the utilities are still unaware of obtaining possible sites and voltage level in power system network. As a result, system faces higher loading levels and unnecessary line tripping thus raising losses and reduced reliability. Pertaining to the database collected of financial year 2018–2019. Due to renewable integration the variable load behavior must be accurately known by the system engineers then only load compensation must be provided. Because presently State Load Dispatch Centers provide instructions to the substations to utilize any available compensation device available in the network to use. This paper underlines a way to access the effects on voltage profile, losses, etc. on power system elements with var support at multiple voltage levels. Case studies for real-time network are detailed, to check the observability for a load of 370 MW. The impact of practices followed is observed for the complete network.

Toward Physicochemical and Rheological Characterization of Different Injectable Hyaluronic Acid Dermal Fillers Cross-Linked with Polyethylene Glycol Diglycidyl Ether.

(1) Background: Injectable hyaluronic acid (HA) dermal fillers are used to restore volume, hydration and skin tone in aesthetic medicine. HA fillers differ from each other due to their cross-linking technologies, with the aim to increase mechanical and biological activities. One of the most recent and promising cross-linkers is polyethylene glycol diglycidyl ether (PEGDE), used by the company Matex Lab S.p.A., (Brindisi, Italy) to create the HA dermal filler PEGDE family. Over the last few years, several studies have been performed to investigate the biocompatibility and biodegradability of these formulations, but little information is available regarding their matrix structure, rheological and physicochemical properties related to their cross-linking technologies, the HA content or the degree of cross-linking. (2) Methods: Seven different injectable HA hydrogels were subjected to optical microscopic examination, cohesivity evaluation and rheological characterization in order to investigate their behavior. (3) Results: The analyzed cross-linked dermal fillers showed a fibrous “spiderweb-like” matrix structure, with each medical device presenting different and peculiar rheological features. Except for HA non cross-linked hydrogel 18 mg/mL, all showed an elastic and cohesive profile. (4) Conclusions: The comparative analysis with other literature works makes a preliminary characterization of these injectable medical devices possible.

Positive Impact of Targeted Educational Intervention in Children With Low Adherence to Growth Hormone Treatment Identified by Use of the Easypod™ Electronic Auto-injector Device

Background: It is important to identify patients with low adherence to recombinant human growth hormone (r-hGH) therapy and initiate actions to improve adherence. The Merck Patient Support Program (PSP) aims to raise the awareness of these patients and their parents of the importance of good adherence in achieving optimal growth outcomes. The easypod™ digitally-enhanced injection device provides accurate, reliable adherence data for the PSP by recording the exact dose, time and date of injections given. In this study, we aimed to measure the effect of an educational intervention on adherence in patients using the easypod™ device to deliver their r-GH therapy.Methods: This was a 12-month observational, retrospective cohort study. Patients previously identified by data recorded from their easypod™ injection device as having low adherence (<80%) were followed over the 6 months before and after a targeted educational visit by a PSP nurse. Patient adherence and demographic data were extracted from the PSP database. Statistical analyzes were carried out with STATA 15.0 software.Results: Data from 80 patients (65% male) with low adherence were analyzed. Patients were aged 2–18 (mean: 11.77) years with diagnoses of growth hormone deficiency (71.25%), small for gestational age (20%), Turner syndrome (7.50%) and chronic renal disease (1.25%). Duration of treatment was 0.40–11.13 (median: 3.62) years. At baseline, median adherence to r-hGH therapy was 67%; after the intervention it increased to 76%, a statistically significant median improvement of 9% (p = 0.0000, Wilcoxon signed-rank test). Additionally, 36% (29/80) of patients increased their adherence to r-hGH therapy to ‘good’ (≥80%). Both changes were clinically relevant.Conclusions: We conclude that a nurse-led educational intervention, supported by digital medication adherence monitoring, is a simple method to improve adherence to r-hGH therapy, and recommend this intervention to reduce the gap between the indication/recommendation of the specialist and patients' behavior.

Multiplex detection of blood-borne pathogens on a self-driven microfluidic chip using loop-mediated isothermal amplification

Detection of blood-borne pathogens such as hepatitis C virus (HCV), hepatitis B virus (HBV) and human immunodeficiency virus (HIV) is essential to ensure the safety of blood transfusion. However, traditional PCR-based pathogen nucleic acid detection methods require relatively high experimental facilities and are difficult to apply in areas with limited resources. In this study, a self-driven microfluidic chip was designed to carry out multiplex detection of HBV, HCV and HIV by using loop-mediated isothermal amplification (LAMP). Benefitting from the air permeability of the polydimethylsiloxane material, the chip could accomplish sample loading within 12min driven by the pressure difference between the reaction chambers and vacuum chambers in the chip without using pumps or any injection devices. Multiplex detection is achieved by presetting LAMP primers specific to different targets in different reaction chambers. Calcein was used as an indicator to indicate the positive amplification reaction, and the result can be recorded by a smartphone camera. After 50min of isothermal amplification at 63°C, 2 copies/μL of HBV, HCV and HIV target nucleic acids could be detected. The results of HBV detection of 20 clinical plasma samples by using the chip are consistent with that of the qPCR-based kit, indicating that the LAMP-based self-driven chip has the clinical application potential for blood-borne pathogen detection, especially in resource-limited areas.

A Stereotactic Device for Intraparenchymal Spinal Cord Injections: Latest Developments for Practical Clinical Use

This manuscript introduces the latest generation of a patient-mounted platform designed for segmental injections of therapeutics direct into the spinal cord parenchyma. It emphasizes its importance and it presents the rationale for developing this delivery methodology. It compares the newest with the previous generations, detailing how the modifications can streamline transportation, assembly, sterilization, and utilization of the platform by different surgeons. Finally, the illustrations depict the main alterations, as well as a cadaveric assessment of the device prototype in the cervical and thoracolumbar regions.

Use of an automatic needle-free injection device for foot-and-mouth disease vaccination in dairy heifers

The foot-and-mouth disease (FMD) vaccination of Thai dairy cows is routinely conducted to control and prevent the disease. In Thailand, FMD control strategies include a subcutaneous route (s.c.) vaccination with 2 ml of inactivated FMD vaccine 2–3 times a year produced by the Department of Livestock Development (DLD). A new way of vaccination was introduced in the form of an automatic needle-free injection device. This technology has several important advantages, such as requiring less animal restraint, reduced time and labour with high precision, and a consistent delivery system. Here, the effectiveness of an automatic needle-free injection (ANFI) device was evaluated in 30 dairy heifers (randomly divided into three groups, 10 in each group) in the FMD vaccine delivery. The first group was subcutaneously (s.c.) vaccinated using a conventional hypodermic needle with 2 ml of the vaccine, the second group received the same, but using a CO&lt;sub&gt;2&lt;/sub&gt;-powered ANFI device, and the third group received the vaccine using the same ANFI device, but administered intradermally (i.d.) with only 1 ml of the vaccine. The blood samples collected up to 120 days post-vaccination revealed that both injection methods resulted in a similar serological response. The results suggest that the i.d. and s.c. ANFI systems are effective and safe. Moreover, the i.d. use of the ANFI enabled the possibility to half the vaccination dose with the same efficacy. Therefore, the ANFI can be used as an alternative approach for FMD vaccination by s.c. or i.d. routes in dairy cows in Thailand. Ultimately, reducing the use of restraint devices and labour will improve the vaccination for the prevention and control of FMD and may improve the cows’ welfare.

Metal–Organic Framework for Efficient Electron Injection

AbstractA 3D metal–organic framework (MOF) [(H3O)Zn(HCOO)3]∞ is developed as a highly efficient and air‐stable solution‐processed electron injection layer (s‐EIL). The [(H3O)Zn(HCOO)3]∞ film can be easily obtained by annealing a spin‐coated [Zn(HCOO)2(H2O)2]∞ film at 120 °C in air, which is facilely prepared by the reaction of ZnO powder with formic acid and the aqueous solution of ammonium. The un‐encapsulated electron‐only device with [(H3O)Zn(HCOO)3]∞ as the s‐EIL exhibits significantly enhanced electrical property and air stability, compared to that with vacuum‐evaporated Cs2CO3 as EIL. Such improvements can also be observed in inverted organic light‐emitting diodes. The device with [(H3O)Zn(HCOO)3]∞ s‐EIL demonstrates an operating voltage of 6.8 V at 1000 cd m−2, much lower than that with Cs2CO3 EIL (8.4 V). And the power efficiency is increased about 18%. The enhanced electron injection property of [(H3O)Zn(HCOO)3]∞‐modified indium–tin oxide (ITO) is attributed to its reduced work function compared to bare ITO, which is confirmed by ultraviolet photoelectron spectroscopy analysis. This approach is anticipated to be applied in other optoelectronic devices for efficient electron injection.

Model of a System-Wide Domestic Hot-Water Distribution System in a Multi-Resident High-Rise Building

AbstractTo reduce the environmental impact and cost, energy and water consumption of multi-resident buildings should be improved while ensuring resident comfort. Inefficient mixing of hot and cold-water streams and a non-optimal domestic hot-water (DHW) distribution system design can cause higher energy consumption, component failures, and dissatisfied residents. An OpenModelica (OM) system-wide model of a 14-story building consisting of a controlled-loop injection (CLI) device and a DHW distribution system is presented. The OM results are validated against field measurements at discreet locations within a single-zone closed-loop circuit to ensure the validity of time-varying temperature and flowrate. The study demonstrates that OM is a useful engineering tool to model single and multi-zone high-rise buildings that allows advanced analysis, including system-wide optimization, advanced on-demand controls, and energy and water-usage efficiencies.

A population-based survey for disabling headaches in Greece: Prevalence, burden and treatment preferences.

To estimate the prevalence, burden and current treatment of disabling primary headaches in a large sample of the Greek population aged 18-70 years old. This is an observational descriptive study, with cross-sectional design performed by quantitative computer-assisted telephone interviews, using a validated 37-item questionnaire for headaches. The prevalence, burden, and current treatment of primary headaches (ICHD-3) were recorded along with participants' treatment preferences. Out of 10,008 interviewed participants, 1197 (12.0%) reported headaches affecting performance. The annual prevalence of migraine was 8.1% (95% confidence interval, 7.6-8.7, corresponding to 0.6 million Greeks), of chronic migraine 1.0% (95% confidence interval, 0.8-1.2, corresponding to 0.1 million), and of tension-type headache 3.8% (95% confidence interval, 3.4-4.2, corresponding to 0.3 million). The participants with headaches reported 0.5 headache-induced lost workdays per month (corresponding to 5.8 million lost workdays annually) and reductions in performance on 2.8 workdays per month (corresponding to 30.9 million workdays annually). In all, 43.4% of headache participants felt bad/ashamed because of headaches and 21.9% sought professional treatment, most often from a private neurologist. 83.8% of headache participants had never taken pharmacological prophylaxis, and only 5.5% were currently under preventative treatment. For both prophylactic and acute treatment, headache participants prefer oral medication to injection or stimulation devices. More than 10% of the Greek adult population up to 70 years old experience disabling headaches, causing a dramatic work loss. More than 80% of these have never taken pharmacological prophylaxis. Thus, enriching the quality of life of people with headaches relies crucially on expanding awareness about headaches and their treatment.

Stability, temperature dependence, and microstructure of high pressure jet-treated dairy foams

The objective of this work was to study the effects of high pressure jet (HPJ) processing on the foaming of whole milk at different temperatures. High pressure jet-treated whole milk (200 and 400 MPa) was foamed at 5, 20, 40, and 50 °C using a custom-made air injection device and the foam expansion and foam stability was compared to a non-HPJ-treated control. Aliquots of the foams (formed at 5 and 50 °C) were extracted for proximate analysis and visualization using confocal scanning laser microscopy (CSLM). The relative foam expansion values for the non-HPJ-treated sample at 5, 20, 40, and 50 °C were 45.5 ± 11.3%, 0 ± 0%, 79.6 ± 9.7%, and 88.2 ± 2.8%, respectively while the 400 MPa-treated sample foam expansion values were 36.4 ± 10.8%, 60.8 ± 5.7%, 50.0 ± 5.3%, and 71.7 ± 3.0%. Notably the HPJ-treated sample foamed at 20 °C while the control milk did not foam at all. Furthermore, the 400 MPa-treated foam was stable for >2 h at all foaming temperatures, unlike the non-HPJ-treated whole milk foam, which completely collapsed in 60 s and 1490 s after being foamed at 5 °C and 40 °C, respectively. CSLM and proximate analysis of the non-HPJ-treated sample revealed differences in foam composition based on foaming temperature with more fat present in the foam formed at 50 °C (3.2 ± 0.3%) than at 5 °C (2.5 ± 0.1%), likely due to the ability of liquid oil (at 50 °C) to migrate to the air-water interface during air incorporation. In contrast, there were no compositional differences in the foams from 400 MPa-treated milk based on foaming temperature, reflecting that there are structural differences, particularly in the fat, compared to the non-HPJ-treated foams. This was supported by evidence of fat-protein complexation and micron-size bubbles in CSLM images of the 400 MPa-treated foam.

Small animal jet injection technique results in enhanced immunogenicity of hantavirus DNA vaccines

DNA vaccine evaluation in small animals is hampered by low immunogenicity when the vaccines are delivered using a needle and syringe. To overcome this technical hurdle we tested the possibility that a device developed for human intradermal medicine delivery might be adapted to successfully deliver a DNA vaccine to small animals. Disposable syringe jet injection (DSJI) does not currently exist for small animals. However, a commercialized, human intradermal device used to to administer medicines to the human dermis in a 0.1 mL volume was evaluated in Syrian hamsters. Here, we found that hantavirus DNA vaccines administered to hamsters using DSJI were substantially more immunogenic than the same vaccines delivered by needle/syringe or particle mediated epidermal delivery (gene gun) vaccination. By adjusting how the device was used we could deliver vaccine to either subcutaneous tissues, or through the skin into the muscle. RNA and/or antigen expression was detected in epidermal, subepidermal and fibroblast cells. We directly compared six optimized and non-optimized hantavirus DNA vaccines in hamsters. Optimization, including codon-usage and mRNA stability, did not necessarily result in increased immunogenicity for all vaccines tested; however, optimization of the Andes virus (ANDV) DNA vaccine protected vaccinated hamsters from lethal disease. This is the first time active vaccination with an ANDV DNA vaccine has shown protective efficacy in the hamster model. The adaptation of a human intradermal jet injection device for use as a method of subcutaneous and intramuscular jet injection of DNA vaccines will advance the development of nucleic acid based medical countermeasures for diseases modeled in hamsters.

Development and content validation of the Satisfaction and Experience Questionnaire for Granulocyte Colony-Stimulating Factor (SEQ-G-CSF)

BackgroundSeveral options for granulocyte colony-stimulating factor (G-CSF) prophylaxis of chemotherapy-induced febrile neutropenia are available to patients worldwide. We have developed a novel patient-reported outcome measure, the Satisfaction and Experience Questionnaire for G-CSF (SEQ-G-CSF), to help understand patients’ perspectives of and satisfaction with different G-CSF options.ResultsThree oncology nurses and 40 adult oncology patients in the United States were enrolled and participated in focus group discussions to develop and refine the SEQ-G-CSF. Nurses had ≥ 5 years of experience treating oncology patients and were currently involved in the management of oncology patients receiving G-CSF prophylaxis. The patients had breast cancer, lung cancer, non-Hodgkin lymphoma, or prostate cancer (10 patients in each group) and were receiving G-CSF prophylaxis via injection or the on-body injector (OBI) device. The preliminary SEQ-G-CSF contained an item relevance questionnaire and three SEQ modules (sociodemographic, medical history, and G-CSF–related healthcare characteristics questionnaires). Twenty-one patients (53% of total sample size) discussed their experience and satisfaction with G-CSF. Their most common experiences were G-CSF effectiveness, convenience and benefits of the OBI, and relationships with healthcare providers. Side effects and having to undergo additional treatment were also reported. Satisfaction with aspects of G-CSF included the OBI and effectiveness of G-CSF treatment; dissatisfaction included inconvenience (having to return to the clinic the next day and administration of the injection) and the insurance approval process. The SEQ-G-CSF was finalized after three rounds of cognitive interviews and includes five domains related to general satisfaction (one item), treatment burden (four items), travel burden (two items), time burden (four items), and treatment compliance (two items).ConclusionsThe SEQ-G-CSF is a novel instrument that quantifies a patient’s experience and satisfaction with different G-CSF options using 13 easy-to-understand items. This study provides evidence for the content validity of SEQ-G-CSF. Although further psychometric testing is required, the SEQ-G-CSF may be a useful addition to clinical trials, observational studies, and clinical practice.

Toward safe environment: injection device disposal among diabetic patients attending tertiary care academic clinic in Middle Delta, Egypt.

In Egypt, there are 8.9 million adult diabetics using almost 16 million insulin injection devices daily. Unsafe disposal of these sharps will result in many environmental and public health hazards. This study aimed at evaluating knowledge and practice of diabetic patients toward safe disposal of insulin injection devices. Cross-sectional study and health education sessions were carried out at diabetic outpatient clinic of the Internal Medicine Department, Tanta University Hospitals in Middle Delta, Egypt, during a period of 2 months (November through December 2019). The study enrolled diabetics who were > 12 years age, using insulin therapy for > 1 year, and females that do not have gestational diabetes. By using systematic random sampling, 450 patients were selected from diabetic patients attending the clinic during the period of the study. Patients' knowledge and practice of insulin injection device disposal were assessed and evaluated using predesigned questionnaire. Verbal health education message and printed pamphlet were given to illustrate safe disposal. Out of the selected samples, 429 completed the questionnaires. Out of those participants, 85.5% had poor knowledge and only 13.5% had good practice. A total of 86.5% dispose at household collection bin, 65.3% reuse syringe, and 63.21% throw it at the nearest garbage bin when takes the injection outside home. Binary logistic regression revealed that female sex (adjusted odds ratio [AOR], 2.37; 95% confidence (CI), 1.13-4.94; p = 0.022), rural residence (AOR, 3.05; 95% CI, 1.62-5.72; p = 0.001) and low income (AOR = 2.11; 95% CI, 1.06-4.18; p = 0.033) were the main predicting sociodemographic factors for poor practice. Meanwhile, syringe usage (AOR = 2.81; 95% CI, 1.31-6.03; p = 0.008), twice daily schedule (AOR = 2.82; 95% CI, 1.51-5.26; p = 0.001), patient himself as injection provider (AOR = 2.268; 95% CI, 1.18-4.36; p = 0.014), and unawareness of how to dispose sharps safely (AOR = 7.33; 95% CI, 3.58-14.99; p < 0.001) were the predicting factors of bad practice related to patient and treatment characteristic. Vast majority of studied diabetic patients do not use or dispose insulin injection devices safely. As the problem is nationwide, an integrated nationwide program is needed including a structured health education module for diabetic patients and a system for collection of home insulin sharps from those patients and disposing them safely.

Field study on axial behavior of instrumented post-grouted steel pipe micropiles in tropical lateritic soil

This paper presents a field study on the axial behavior of new configuration of steel pipe micropiles in tropical lateritic soil. The micropiles were installed following a two-step grouting process with high injection pressures at a new experimental site located at the University of Campinas (Unicamp). The main innovation of the micropiles relies on the use of high-strength steel pipes as a drilling tool, casing protection, structural component and injection device. Full-scale pile loading tests were performed under compression and tension loads to investigate the axial behavior of the micropiles. The micropiles were instrumented along the shaft with electrical extensometers, and they were monitored during the progress of the loading tests. The load–movement responses, elastic moduli, axial load transfer mechanism, and unit bond stress relating to the micropiles and their interactions with the tropical soil were measured and evaluated. The bearing capacity of the post-grouted micropiles was considerably improved by the proposed post-grouting technique. The ultimate load capacity of the grouted steel pipe micropile under a compression load is approximately the same under a tension load. The average ultimate bond strength was 99 kPa and 100 kPa for the micropile under compression and tension, respectively. The distribution of unit bond stress along the shaft of the micropile under compressive and tensile load presented a post-peak softening behavior. The average ultimate grout-to-ground strength at the soil–micropile interface was 2.4 and 1.7 times greater than other nongrouted and non-injected piles installed in the same soil conditions at Unicamp.

Transdermal Delivery of Adipocyte Phospholipase A2 siRNA using Microneedles to Treat Thyroid Associated Ophthalmopathy-Related Proptosis

Thyroid associated ophthalmopathy (TAO) is an organ-specific autoimmune disease occurring in patients with thyroid disease. Patients with TAO-related proptosis is largely due to excessive orbital adipose tissue Adipocyte phospholipase A2 (AdPLA) is one of the most important regulatory factors in adipocyte lipolysis, which may be associated with TAO-related proptosis. Thus, silencing AdPLA by RNA interference may be beneficial for the treatment of TAO. In this study, we sought to evaluate the efficiency of two types of microneedles to deliver siRNAs for silencing AdPLA. Our results showed that AdPLA mRNA was up-regulated in the orbit adipose tissues from TAO patients. Silence of AdPLA by siRNA can reduce lipid accumulation in both human and mouse adipocyte cell lines. Moreover, silence effects of silicon microneedle array patch-based and injectable microneedle device-based siRNA administration were examined at the belly site of the mice, and injectable microneedle device showed higher knockdown efficiency than silicon microneedle array patch. This study sets the stage not only for future treatment of TAO-related proptosis using AdPLA siRNA, but also provides the foundation for targeted siRNA delivery by using microneedles.

Volume Conduction for Powering Deeply Implanted Networks of Wireless Injectable Medical Devices: A Numerical Parametric Analysis

The use of networks of wireless active implantable medical devices (AIMDs) could revolutionize the way that numerous severe illnesses are treated. However, the development of sub-mm AIMDs is hindered by the bulkiness and the transmission range that consolidated wireless power transfer (WPT) methods exhibit. The aim of this work is to numerically study and illustrate the potential of an innovative WPT technique based on volume conduction at high frequencies for powering AIMDs. In this technique, high frequency currents are coupled into the tissues through external electrodes, producing an electric field that can be partially picked-up by thin, flexible, and elongated implants. In the present study, the system formed by the external electrodes, the tissues and the implants was modeled as a two-port impedance network. The parameters of this model were obtained using a numerical solver based on the finite element method (fem). The model was used to determine the power delivered to the implants’ load (PDL) and the power transmission efficiency (PTE) of the system. The results allow the identification of the main features that influence the PDL and the PTE in a volume conduction scenario and demonstrate that volume conduction at high frequencies can be the basis for a non-focalized WPT method that can transfer powers above milliwatts to multiple mm-sized implants (< 10 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> ) placed several centimeters (>3 cm) inside the tissues.

Theoretical research and application development of self-sensing micro-flow injection device

In this study, the main content is based on theory and application of piezoelectric ceramic digital micro-injection, analyzing the first inverse piezoelectric effect and secondary positive piezoelectric effect of piezoelectric ceramics through theory and experiments, and using its principle to design self-sensing digital micro-injection structure. This paper designs a kind of digital micro-injection device which is based on the first inverse and secondary positive piezoelectric effect by according to the theoretical research and experimental verification of piezoelectric ceramic’s piezoelectric effect. Push the syringe plunger under the action of the piezoelectric ceramic’s first reverse piezoelectric effect to achieve a fluid flowing. At the same time, secondary piezoelectric effect can sense the injection volume to achieve self-sensing microinjection. Designing the overall structure of the program and validate the feasibility of the program is reasonable and practicable through feasibility experiments.