Device Size Research Articles

Transjugular Transcatheter Tricuspid Valve Replacement: Early Compassionate Use Outcomes

BackgroundData on procedural and early outcomes after transjugular transcatheter tricuspid valve replacement (TTVR) are limited. ObjectivesThis study sought to evaluate first-in-man procedural and clinical outcomes after transjugular TTVR with a special focus on patients who received large device sizes in whom TTVR outcomes have been questioned. MethodsThe retrospective registry included patients who underwent TTVR using the LuX-Valve Plus system (Jenscare Biotechnology Co Ltd) for symptomatic tricuspid regurgitation (TR) from January 2022 until February 2024 at 15 international centers in a compassionate use setting. The endpoints were procedural TR reduction, in-hospital death, adverse events, and 1-month survival. We further stratified results according to the size of the implanted device (<55 vs ≥55 mm). ResultsThe registry included a total of 76 patients at a median age of 78 years (Q1-Q3: 72-83 years, 47.4% women). TR was reduced to ≤2+ and ≤1+ in 94.7% and 90.8% of patients (75.0% of patients received TTVR devices ≥55 mm) with well-sustained results at 1-month follow-up (TR ≤2+ in 95.0% and ≤1+ 86.8%). Residual TR was paravalvular in all cases. In-hospital death occurred in 4 patients (5.3%). Four patients (5.3%) underwent cardiac surgery during index hospitalization. Major in-hospital bleeding events occurred in 5 patients (6.6%). New in-hospital pacemaker implantation was required in 3.9% of patients in the overall cohort (5.7% in “pacemaker-naive” individuals). No cases of valve thrombosis, stroke, myocardial infarction, or pulmonary embolism were observed. At 1-month follow-up, survival was 94.4%, and NYHA functional class significantly improved. One further patient received a pacemaker, 1 further bleeding event occurred, and 2 patients underwent reintervention or surgery within the first 30 days after TTVR. No differences in procedural outcomes or adverse events were observed after stratification for valve size. ConclusionsTransjugular TTVR appears to be a safe and effective treatment option for patients with severe TR with comparable outcomes in very large tricuspid anatomies.

Optimal allocation of wind power hybrid energy storage capacity based on ant colony optimization algorithm

Renewable energy sources, such as wind power, face challenges owing to their erratic construction and intermittent nature, leading to the emergence of energy storage strategies to achieve grid stability and reliable electricity supplies. Determination of the correct size of energy storage devices for wind power plants is complicated. In this study, the ant colony optimization (ACO) algorithm is proposed for the best distribution/sizing of wind-generated hybrid storage capacity. Ants’ foraging habits motivate the development of wind turbines with high dependability, high efficiency and low energy storage costs. A study is conducted to confirm the practicality of the proposed method, using real data from a wind power plant to calculate the contrast between wind energy production and load consumption features, to influence the appropriate quantity for energy storage organization. The study demonstrates that the ACO approach provides precise and efficient solutions for determining the optimal energy distribution in wind power plants.

Resistive random-access memories using quasi-2D halide perovskites for wafer-scale reliable switching behaviors

In this study, we propose the (PEA)2MA3Pb4I13, a quasi-two-dimensional (2D) halide perovskite, in the realm of resistive switching memory devices. A quasi-2D perovskite film (PEA)2MA3Pb4I13, with a thickness measuring 450 nm, has been effectively fabricated on a silicon substrate coated with platinum through an all-solution process conducted at low temperatures. The constructed resistive switching memory devices, incorporating an Ag/(PEA)2MA3Pb4I13/Pt/Ti/SiO2/Si configuration, display dependable and consistent bipolar switching attributes. The device shows an ultra-low operating voltage of less than +0.1 V, an impressive high ON/OFF ratio exceeding 108, reversible resistive switching via pulse voltage operation, and the capability for multilevel data storage. In addition, there is little variation in device characteristics depending on the location on a wafer or device size.

High-Sensitivity Curvature Fiber Sensor Based on Miniature Two-Path Mach-Zehnder Interferometer.

This paper introduces a new high-sensitivity curvature fiber sensor based on a miniature two-path Mach-Zehnder interferometer (MTP-MZI). The sensor is fabricated by coupling and fusing the multimode fiber (MMF) with the single-mode fiber (SMF) using arc fusion technology (AFT), resulting in a centimeter-level two-path MZI structure. The sensor represents an innovative approach to MZI coupling technology, which reduces device size, simplifies manufacturing, and lowers costs. In curvature-sensing experiments, the MTP-MZI sensor achieves a maximum curvature sensitivity of -96.70 dB/m-1 in the curvature range of 0.0418 m-1 to 0.0888 m-1, which is an extremely high sensitivity among intensity-modulated curvature sensors. Additionally, temperature-sensing measurements of the MTP-MZI sensor show a maximum temperature sensitivity of 212 pm/°C in the range of 30 °C to 70 °C, which is low temperature sensitivity and solves the cross-sensitivity problem. Thanks to the miniature two-path structure of the MTP-MZI, it provides a new perspective for developing multidimensional and multiparameter measurement methods in MZI fiber sensors.

Transcatheter closure of perimembranous ventricular septal defect using the cocoon membranous VSD occluder

BackgroundTranscatheter device closure is a well-established treatment for suitable ventricular septal defects (VSDs). The Cocoon Membranous VSD Occluder is a relatively new device specifically designed for perimembranous VSDs. Existing research on the Cocoon Membranous VSD Occluder for closing PM VSD is limited. ObjectiveThis study aimed to describe a single-center experience using the Cocoon Membranous VSD Occluder for perimembranous VSD. MethodsWe retrospectively analyzed data from patients who underwent device closure of perimembranous VSD using the Cocoon occluder between May 2023 and April 2024. Procedural success, complications, and short-term outcomes were evaluated. ResultsBetween May 2023 and April 2024, 13 patients with perimembranous VSD and left-to-right shunt underwent device closure with the Cocoon Membranous VSD Occluder. Twelve patients (92.3 %) achieved successful VSD closure. The mean age was 8.06 years with standard deviation (SD) of 7.24 years. The mean weight was 11.98 kg with SD of 18.93 kg. The mean VSD size was 4.96 mm with SD of 0.92 mm. The VSD was crossed from the right ventricle in 5 patients and from the left ventricle in 9 patients. All patients had successful device placement from the right ventricle approach. The Cocoon Membranous VSD device size ranged from 6 to 4 mm to 12–4 mm. In one smaller patient, the device was electively removed due to significant flow through an additional exit, and the patient subsequently underwent surgery. Another patient developed hemoglobinuria on the fourth day, which resolved by the tenth day with hydration therapy. Two patients experienced trivial to mild aortic regurgitation, and one had Wenckebach phenomenon that resolved the next day. In the short-term follow-up (mean duration of 4.33 months), all patients were doing well, had good device performance, and showed no evidence of heart block. ConclusionsDevice closure of perimembranous VSD in infants with the Cocoon Membranous VSD Occluder appears to be safe and effective in carefully selected patients during short-term follow-up. Larger studies with long-term data are necessary for future recommendations.

Electrically Reconfigurable Phase-Change Transmissive Metasurface.

Programmable and reconfigurable optics hold significant potential for transforming a broad spectrum of applications, spanning space explorations to biomedical imaging, gas sensing, and optical cloaking. The ability to adjust the optical properties of components like filters, lenses, and beam steering devices could result in dramatic reductions in size, weight, and power consumption in future optoelectronic devices. Among the potential candidates for reconfigurable optics, chalcogenide-based phase change materials (PCMs) offer great promise due to their non-volatile and analogue switching characteristics. Although PCM have found widespread use in electronic data storage, these memory devices are deeply sub-micron-sized. To incorporate phase change materials into free-space optical components, it is essential to scale them up to beyond several hundreds of microns while maintaining reliable switching characteristics. This study demonstrated a non-mechanical, non-volatile transmissive filter based on low-loss PCMs with a 200 × 200 µm2 switching area. The device/metafilter can be consistently switched between low- and high-transmission states using electrical pulses with a switching contrast ratio of 5.5 dB. The device wasreversibly switched for 1250 cycles before accelerated degradation took place. The work represents an important step toward realizing free-space reconfigurable optics based onPCMs.

Dual banyan network (DBN) design: A quantum-dot cellular automata (QCA) based approach

The inputs use a non-blocking internal process to distribute the data using address of the port of the receiver using a non-blocking interior multistage transmission architecture known as a dual banyan network (DBN). The DBN is a primary component in many communication and switching applications because it efficiently routes and switches data packets. This study shows how to construct a single-layer DBN using QCA. A single layer 2 × 2 crossbar network (CBN) with two inputs and two outputs is suggested and developed in QCA to create the proposed communication architecture. In this study, a 2 × 2 CBN is used as a preliminary building block to create a 4 × 4 DBN. We present a detailed analysis of the DBN design, including its architecture, functionality, and performance evaluation. For a fault-free crossbar switch design, the consequence of a fault that affects the control line is noticed and surpassed. Similarly, the proposed architectures' fault tolerance has been described by considering fault scenarios at the 2 × 2 CBN control lines. Considering the logic gates, number of clock cycles, and device size complexity of the designs are measured. All of the designs were implemented using QCADesigner software. The power dissipation of the suggested layouts.

Shear Thickening Fluid and Sponge-Hybrid Triboelectric Nanogenerator for a Motion Sensor Array-Based Lying State Detection System.

Issues of size and power consumption in IoT devices can be addressed through triboelectricity-driven energy harvesting technology, which generates electrical signals without external power sources or batteries. This technology significantly reduces the complexity of devices, enhances installation flexibility, and minimizes power consumption. By utilizing shear thickening fluid (STF), which exhibits variable viscosity upon external impact, the sensitivity of triboelectric nanogenerator (TENG)-based sensors can be adjusted. For this study, the highest electrical outputs of STF and sponge-hybrid TENG (SSH-TENG) devices under various input forces and frequencies were generated with an open-circuit voltage (VOC) of 98 V and a short-circuit current (ISC) of 4.5 µA. The maximum power density was confirmed to be 0.853 mW/m2 at a load resistance of 30 MΩ. Additionally, a lying state detection system for use in medical settings was implemented using SSH-TENG as a hybrid triboelectric motion sensor (HTMS). Each unit of a 3 × 2 HTMS array, connected to a half-wave rectifier and 1 MΩ parallel resistor, was interfaced with an MCU. Real-time detection of the patient's condition through the HTMS array could enable the early identification of hazardous situations and alerts. The proposed HTMS continuously monitors the patient's movements, promptly identifying areas prone to pressure ulcers, thus effectively contributing to pressure ulcer prevention.

Photonic-crystal-based hybrid wavelength-mode division multiplexer for SOI platforms

This paper presents a 12-channel hybrid wavelength-mode division multiplexer (WDM-MDM) based on 2D photonic crystals. The proposed device consists of microring resonators (MRRs) and asymmetric directional couplers (ADCs) to perform three-channel wavelength division multiplexing and four-channel mode division multiplexing operations, respectively. Each MRR can work bi-directionally, providing the same wavelength channels separately in two drop ports. The bus waveguides in the cascaded ADCs are optimized to convert the fundamental modes to the corresponding higher-order modes and are connected through taper regions for the smooth transition of modes. The designed device is simulated using the finite-difference time-domain solver, achieving a maximum channel spacing and insertion loss of 5.05 nm and 0.97 dB, respectively. The device size of the proposed WDM-MDM is 74.98µm×32.82µm. The fabrication tolerance study is performed for uniform over-etch and under-etch conditions. The temperature tolerance study on the resonant wavelength is performed, and the temperature coefficient shift of &lt;0.0254nm/K is achieved. The proposed device can potentially increase the channel capacity for on-chip high-density optical interconnects.

High Frequency and Addressable Impedance Measurement System for On-Site Droplet Analysis in Digital Microfluidics

Digital microfluidics is a novel technique for manipulating discrete droplets with the advantages of programmability, small device size, low cost, and easy integration. The development of droplet sensing methods advances the automation control of digital microfluidics. Impedance measurement emerges as a promising technique for droplet localization and characterization due to its non-invasive nature, high sensitivity, simplicity, and cost-effectiveness. However, traditional impedance measurement approaches in digital microfluidics based on the high-voltage actuating signal are limited in sensing accuracy in practical applications. In this paper, we propose a novel droplet impedance sensing system for digital microfluidics by introducing a low-voltage and addressable measurement circuit, which enables impedance measurement over a wide frequency range. The proposed measurement system has also been used for detecting the droplet composition, size, and position in a digital microfluidic chip. The improved impedance sensing method can also promote the applications of the digital microfluidic, which requires high accuracy, real-time, and contactless sensing with automatic sample pretreatment.

Treatment of Iron-Induced Cutaneous Hyperpigmentation With Energy-Based Devices.

Iatrogenic cutaneous siderosis is a well-recognized dermatologic complication after parenteral iron infusion. The condition manifests as discrete, hyperpigmented patches near the site of injection. Most cases do not resolve spontaneously, leading to significant aesthetic and psychological distress to patients. A recent case of iatrogenic cutaneous siderosis at our institution prompted a systematic review of the efficacy of energy-based devices previously reported in the treatment of this condition. PubMed and Cochrane databases were searched for all peer-reviewed articles published using the following search terms: "iron OR heme OR hemosiderosis OR siderosis" and "hyperpigmentation OR staining OR tattoo." Articles reporting on energy-based devices in the treatment of iron-induced hyperpigmentation were included. A total of seven articles and 54 total patients were included in this review. All patients, including the patient treated at our institution, were female, with an average age of 44 years. Hyperpigmentation was most commonly associated with intravenous iron infusion (48/54, 89%), on the arm or forearm (44/54, 81%), and used for the treatment of underlying iron deficiency anemia (54/54, 100%). The application of six different nanosecond or picosecond quality-switched laser systems was reported in the treatment of cutaneous siderosis, with wavelengths ranging from 532 to 1064 nm. Spot sizes varied between 2 and 7 mm, with energy fluences spanning 0.5-40 J/cm2 depending on both the device and spot size. Outcomes were measured after an average of 5.4 laser treatments and 10.4 months, with over half of all reported patients experiencing complete clearance (27/50, 54%). Our patient received treatment inthree test areas withpicosecond alexandrite 785 nm, nanosecond Nd:YAG 532 nm, and picosecond Nd:YAG 532 nm devices. The nanosecond Nd:YAG 532 nm treated area demonstrated the greatest improvement,and the entire arm was subsequently treated with this device. Despite the often intractable nature of iatrogenic cutaneous siderosis, laser surgery is a reasonable and safe treatment modality for patients seeking cosmetic improvement of this dyschromia. Dermatologists should be aware of this entity and the efficacy of the energy-based devices currently in our armamentarium. A combination approach may need to be utilized with different wavelengths and pulsed widths to target iron pigment in both dermal and subcutaneous layers.

Fully Printed Multilayer Ceramic Capacitors Based on High-k Perovskite Nanosheets.

Printing technology enables the integration of chemically exfoliated perovskite nanosheets into high-performance microcapacitors. Theoretically, the capacitance value can be further enhanced by designing and constructing multilayer structures without increasing the device size. Yet, issues such as interlayer penetration in multilayer heterojunctions constructed using inkjet printing technology further limit the realization of this potential. Herein, a series of multilayer configurations, including Ag/(Ca2NaNb4O13/Ag)n and graphene/(Ca2NaNb4O13/graphene)n (n = 1-3), are successfully inkjet-printed onto diverse rigid and flexible substrates through optimized ink formulations, inkjet printing parameters, thermal treatment conditions, and rational multilayer structural design using high-k perovskite nanosheets, graphene nanosheets and silver. The dielectric performance is optimized by fine-tuning the number of dielectric layers and modifying the electrode/dielectric interface. As a result, the graphene/(Ca2NaNb4O13/graphene)3 multilayer ceramic capacitors exhibit a remarkable capacitance density of 346±12nFcm-2 and a high dielectric constant of 193±18. Additionally, these devices demonstrate moderate insulation properties, flexibility, thermal stability, and chemical sensitivity. This work shed light on the potential of multilayer structural design in additive manufacturing of high-performance 2D material-based ceramic capacitors.

Microscale Lateral Perovskite Light Emitting Diode Realized by Self-Doping Phenomenon.

High-definition near-eye display technology has extremely close sight distance, placing a higher demand on the size, performance, and array of light-emitting pixel devices. Based on the excellent photoelectric performance of metal halide perovskite materials, perovskite light-emitting diodes (PeLEDs) have high photoelectric conversion efficiency, adjustable emission spectra, and excellent charge transfer characteristics, demonstrating great prospects as next-generation light sources. Despite their potential, the solubility of perovskite in photoresist presents a hurdle for conventional micro/nano processing techniques, resulting in device sizes typically exceeding 50 μm. This limitation impedes the further downsizing of perovskite-based components. Herein, we propose a plane-structured PeLED device that can achieve microscale light-emitting diodes with a single pixel device size < 2 μm and a luminescence lifetime of approximately 3 s. This is accomplished by fabricating a patterned substrate and regulating ion distribution in the perovskite through self-doping effects to form a PN junction. This breakthrough overcomes the technical challenge of perovskite-photoresist incompatibility, which has hindered the development of perovskite materials in micro/nano optoelectronic devices. The strides made in this study open up promising avenues for the advancement of PeLEDs within the realm of micro/nano optoelectronic devices.

Perventricular device closure of the ventricular septal defects in children-first experience in the United Arab Emirates

BackgroundVentricular septal defect (VSD) is the most common congenital cardiac malformation, accounting for approximately 30% of congenital heart defects. Conventional surgical repair using cardiopulmonary bypass is invasive and associated with morbidities and prolonged hospital stay. With the advent of interventional approaches and availability of different occluding devices, the technique of perventricular device closure is evolving and being implemented successfully in larger groups of patients. We present herein, our initial experience of perventricular device closure for the ventricular septal defects in children to assess risks and benefits.MethodsFrom March, 2023 to February, 2024, we have performed perventricular closure of ventricular septal defects in 13 children, under guidance of transesophageal echocardiography without cardiopulmonary bypass support. The median age at operation was 2 year (range 1.3–10 years) with the median body weight 11 kg (range 8.7–16.6 kg). Sixty-nine percent were males. The ventricular septal defect sizes ranged from 2.7 to 6 mm (mean 4.7 mm). Seven defects were perimembranous, four sub-aortic and two were muscular. One patient also underwent pulmonary artery de-banding with pulmonary artery balloon angioplasty and other one patent ductus arteriosus ligation, concomitantly. For defect closure, we used ventricular septal defect occlusion device (MemoPart™, Lepu Medical Technology Company, China) through a 3-cm skin incision in the lower- third of the sternum. The device sizes ranged from 5 to 8 mm (mean 6.9+-1.8 mm) and all patients except for two required symmetrical devices.ResultsAll patients underwent device closure successfully. The procedural duration ranged between 32 and 52 min. None of the patients required cardiopulmonary bypass. The mean ventilation time and intensive care unit stay was 3 and 24 h, respectively. None of the patients required inotropic support or blood transfusions. Moreover, no patients developed any arrhythmias including heart block. The average length of hospital stay was 4.4 days. At the latest follow up, there were no residual shunts, conduction disturbances, device dislodgement or major aortic or tricuspid valve complications seen in any patients. There was no mortality.ConclusionsPerventricular device closure of ventricular septal defects is a less invasive, extremely safe and effective method in children. It is associated with very fast recovery, shorter hospitalization time and better cosmetic incision. Moreover, it avoids cardiopulmonary bypass. The modifications and refinements in the design, material and implantation techniques will help in expanding the indications and prevent complications in the long-term.

Reduction in Balloon Pump Size Reduces Axillary Intraaortic Balloon Pump Failure Risk.

Axillary artery intra-aortic balloon pump (axIABP) placement has been implemented as a bridging solution before heart transplantation. This study evaluates complications associated with axIABP support and describes an approach to minimize adverse events. We previously described a percutaneous approach for axIABP placement. However, patients receiving axIABP between September 1, 2017, and September 26, 2019 (n = 32) demonstrated a high rate of balloon pump malfunction (8/32; 25%) and other complications (totaling 15/32; 47%). Sixty-four patients were sequentially treated under a revised protocol. Compared to the initial cohort, no significant differences in demographics were noted. A significant reduction in rate of balloon malfunction (8/32, 25% vs. 1/64, 2%; p < 0.001) and total complications (15/32, 47% vs. 10/64, 16%; p = 0.0025) during the period of support were noted after intervention. Subsequent analysis of total complications per device size (40 vs. ≤ 34 ml balloon) revealed significantly reduced complications in patients with smaller devices (40% vs. 13%, respectively; p = 0.0022). This study provides guidelines to limit complications in patients supported with axIABP, facilitating a protracted period of bridging support.

Are comparable studies really comparable? Suggestions from a problem-solving experiment on urban and rural great tits

Performance in tests of various cognitive abilities has often been compared, both within and between species. In intraspecific comparisons, habitat effects on cognition has been a popular topic, frequently with an underlying assumption that urban animals should perform better than their rural conspecifics. In this study, we tested problem-solving ability in great tits Parus major, in a string-pulling and a plug-opening test. Our aim was to compare performance between urban and rural great tits, and to compare their performance with previously published problem solving studies. Our great tits perfomed better in string-pulling than their conspecifics in previous studies (solving success: 54%), and better than their close relative, the mountain chickadee Poecile gambeli, in the plug-opening test (solving success: 70%). Solving latency became shorter over four repeated sessions, indicating learning abilities, and showed among-individual correlation between the two tests. However, the solving ability did not differ between habitat types in either test. Somewhat unexpectedly, we found marked differences between study years even though we tried to keep conditions identical. These were probably due to small changes to the experimental protocol between years, for example the unavoidable changes of observers and changes in the size and material of test devices. This has an important implication: if small changes in an otherwise identical set-up can have strong effects, meaningful comparisons of cognitive performance between different labs must be extremely hard. In a wider perspective this highlights the replicability problem often present in animal behaviour studies.

P-730 A feasibility study of the impact of the level of exposure to ambient air pollutants on outcomes of assisted reproductive technologies

Abstract Study question What is the impact of air pollution exposure on outcomes for couples having IVF treatment? Summary answer Environmental exposure to high levels of air pollutants may negatively influence IVF outcomes with potential implications for fertility treatment. What is known already Air pollutants are harmful substances in the atmosphere that have adverse effects on human health. Increased levels of air pollutants have been associated with respiratory disorders, cardiovascular disease, and increased morbidity in humans across all age groups. Existing evidence suggests that increased exposure to air pollutants may adversely affect fertility. The relationship between air pollutants and IVF outcomes remains poorly understood. Study design, size, duration This was an ethically approved prospective observational feasibility study conducted over a two-year period. Ten couples due to undergo an IVF cycle were recruited from a fertility centre in the UK. Environmental exposure to ambient air pollutant for particulate matter (PM) 2.5 and 10 micron size was measured using portable AirBeam monitors over the course of two weeks from commencement of the ovarian stimulation regime. Participants/materials, setting, methods Eligible participants were those aged 18-35 years old, undergoing fresh IVF, with a good ovarian reserve and ability to provide informed consent. Data of interest included: BMI, age, parity, ethnicity, smoking status. IVF data included: number of oocytes retrieved, embryo quality and cycle outcomes. AirBeam device data was extracted, analysed and correlated with IVF outcomes. Participants feedback was sought for qualitative input for future studies. Main results and the role of chance Total of 28,269 data points of ambient air pollutant data for PM 2.5 and 10 micron size were recorded amongst the ten participants. One participant was exposed to significantly high air pollutant levels during ovarian stimulation on certain days (PM2.5 - 81.06 µg/m³ and PM10 - 154.48 µg/m³) compared to standard annual air pollution level for the UK of 25 µg/m³ for PM2.5 and 40 µg/m³ for PM10. Two women did not have embryo transfer due to embryo arrest. Of those who had transfer, 50% (n = 4) had positive pregnancy tests however three experienced early pregnancy losses. At the time of writing there was one ongoing single viable pregnancy. On correlation of air quality data with clinical outcomes, the one participant who exhibited fluctuant very high exposure levels to the measured air pollutants, had unexpected low fertilization rate (20%) with IVF and no transfer due to embryo arrest. Of the nine participants returning the questionnaire feedback, all but one rated it acceptable to most acceptable to carry the device around. The main barrier was the size of device and battery life. All respondents were willing to recommend others to participate in a future similar study confirming feasibility to recruit. Limitations, reasons for caution As a feasibility study, with a limited sample size, our findings should be interpreted cautiously. The small cohort limits the generalisability of our results. Further research with larger sample sizes is required to validate our findings. Wider implications of the findings Understanding the impact of air pollutants on IVF outcomes is important for developing evidence-based guidance and interventions to optimise fertility treatment efficacy. Our study demonstrates the feasibility of personal air quality monitoring and emphasises the necessity for larger scale research and the practicality of pollutant exposure measurements in fertility treatments. Trial registration number REC reference: 21/NE/0233 IRAS project ID: 294240. Theramex BIRTH Grant

Long-Term Outcomes of Percutaneous Trans-catheter Device Closure of Atrial Septal Defects During Teenage Life versus Adulthood

Abstract Aim and Objectives To evaluate the long-term follow up outcome of patients who underwent percutaneous trans-catheter closure of atrial septal defects during teenage life versus adulthood. Patients and Methods The study included 100 patients with secundum type ASD were treated by transcatheter closure of their defects. Two year after the procedure patients included in the study were subjected to thorough history taking, physical examination,12 leads surface electrocardiogram and Holter. Full 2D and Doppler echocardiographic study was performed in addition to Tissue Doppler Assessment of left ventricular function. Results At the 2 years follow up of transcatheter ASD closure, the RVEDD had decreased from 22.93±5.889 mm to 18±4.06 mm(P = 0.000). By comparing 2D echocardiographic parameters between teenagers and adults there was a highly significant difference in RV basal diameter (P = 0.004), RV systolic function (P = 0.000), RA area (P = 0.030). Mean PAP decreased from 18.37±4.796 mmHg to 14.77±4.75 mmHg (P = 0.022). RVSP decreased from 28.9±4.425 mmHg to 15.83±4.17 mmHg (P = 0.000). There was statistically significant difference regarding defect size (P = 0.037), device size (P = 0.038) and Holter findings (P = 0.042) while there was no statistically significant difference between both groups regarding mPAP, device type and ECG. Defect size was larger in adult group ranged from 9 to 33 mm with mean ± SD 15.57 ± 6.57 mm than teenagers ranged from 6 to 22 mm with mean ± SD 13.06 ± 5.18 mm. Also, incidence of arrhythmia in adults was higher than teenagers as follows: PACs was in 7 patients (14 %) in adult group while 3 patients (6 %) had PACs in teenagers group and paroxsymal AF was found in 4 patients (8 %) in adult group while no patients in teenagers develop AF. All the patients had normal sinus rhythm before closure and no one developed arrhythmia until 1 year after closure. 50 % of the patients had normal RV size at the 2-year follow up. Regarding Doppler parameters, mitral E/A ratio (P = 0.000) and lateral E/e' ratio (P = 0.041) had significant difference between adults and teenagers as shown in table (8) mostly related to age. Mitral E/A ratio in adults ranged from 0.7 to 1.5 with mean ± SD 1.06 ± 0.20 while in teenagers ranged from 1.1 to 1.8 with mean ± SD 1.45 ± 0.17. Lateral E/e’ ratio in adults ranged from 3 to 7.9 with mean ± SD 5.43 ± 1.24 while in teenagers ranged from 3 to 7 with mean ± SD 4.94 ± 1.13. Conclusion Transcatheter ASD closure leads to a significant improvement in heart cavity dimensions and RV function and reversal of electrical and mechanical changes. Novel parameters for assessment of RV function are promising and appear to be helpful for the assessment of RV function and its response to correction of volume. Key words: Atrial septal defect, arrhythmia, transcatheter closure, adults, teenagers. Abbreviations and Acronyms 2D: Two-Dimensional 3D:Three-dimensional ASD(s): Atrial septal defect(s) BSA: Body surface area CHDs: Congenital heart defects ECG: Electrocardiogram EF: Ejection fraction FAC: Fractional Area Change LA: Left Atrium mPAP: mean Pulmonary Artery Pressure RA: Right Atrium RAA: Right atrial area RBBB: Right Bundle Branch Block RV : Right Ventricle TEE : TransEsophgyeal Echocardiography TTE : TransThoracic Echocardiography

Design of a 1 × 3 Power Splitter Based on Multimode Interference in a Parabolic-Type Slot-Waveguide Structure

Multimode interference (MMI) couplers based on silicon slot-waveguide structures have received widespread attention in recent years. The key issues that need to be addressed are the size and loss of such devices. This study introduces a 1 × 3 silicon-based slot-waveguide multimode interference power splitter. The device uses a gallium-nitride slot-waveguide structure to reduce the length of the coupling region and decrease additional losses. To reduce the width of the coupling region, the multimode interference coupling area is designed with a parabolic-shaped structure. The introduction of a tapered structure between the input/output waveguides and the coupling region improves additional losses and non-uniformity. Furthermore, we conducted an analysis of the fabrication tolerances of the coupling region. In this paper, we use mode solution to simulate the design of the device in the 1550 nm optical wavelength range. The eigenmode expansion method is used to simulate and optimize the parameters of the device. The device is simulated using the eigenmode expansion solver. The simulation results show that the total length of the coupling region for the device is only 4 μm. The normalized transmission of the device is 0.992, and its excess loss and imbalance are 0.036 dB and 0.003 dB, respectively. The proposed power splitter can be applied to integrated optical circuit design, optical sensing, and optical power measurement.

3D packaging and Moore’s Law

Abstract This paper describes how the semiconductor industry has seen steady improvements in key metrics such as performance, power consumption, and area, but as the semiconductor industry shrinks in device size and the technical challenges of ever-increasing performance demands, it is critical to improve chip performance for maximizing the operating frequency of individual ICs and reducing their power consumption. But when talking about improving chip performance, it is important not to focus solely on the individual integrated circuit (IC), but to evaluate it as part of the overall system. For example, as microprocessor frequency increases, so does the demand for main memory data. However, if the connections between the chips that transfer data to the processor do not keep pace with the increase in performance, these connections can become a bottleneck in the performance of the entire system. Instead, this paper describes a typical architecture for semiconductor 3D integration, highlights the technology choices for 3D integration implementation, and analyzes and explains the design challenges it presents. After outlining the above, this paper also analyzes the applications and achievements of 3D integration technology in recent years.