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This paper presents a low profile cylindrical cavity quadruple-mode dual-band bandpass filter. Five short-circuited metal pillars are loaded in a cylindrical cavity to change the electric field distributions of the original resonant modes. The changed TM 010 mode and TM 110+ mode form the first passband, and the changed TM 110- mode and TM 210+ mode form the second passband. The center frequencies of the two passbands are 3.05 GHz and 3.59 GHz, with relative bandwidths of 1.72% and 2.5%, respectively. The first passband can be adjusted independently, and the stopband range of the proposed bandpass filter is relatively wide. By using the degenerate modes, two transmission zeros are introduced to improve the selectivity of the proposed bandpass filter. The use of TM mn 0 mode effectively reduces the height of the cavity. The fabricated cavity bandpass filter is measured, and the measured results are accordance with the simulated ones. [ABSTRACT FROM AUTHOR]

Microstrip antennas are high gain aerials for lowprofile wireless applications working with frequencies over 100 MHz. This paper presents a study and design of a low cost slotted-type microstrip patch antenna that can be used in 5G millimeter wave applications. This research focuses on the effect of ground slots and patch slots which, in turn, affect different antenna parameters, such as return loss, VSWR, gain, radiation pattern, and axial ratio. The working frequency range varies from 24 to 28 GHz, thus falling within 5G specifications. A subset of artificial intelligence (AI) known as particle swarm optimization (PSO) is used to approximatively solve issues involving maximization and minimization of numerical values, being highly challenging or even impossible to solve in a precise manner. Here, we have designed and analyzed a low-profile printed microstrip antenna for 5G applications using the AIbased PSO approach. The novelty of the research is mainly in the design approach, compactness of size and antenna applicability. The antenna was simulated with the use of HFSS simulation software. [ABSTRACT FROM AUTHOR]

The aim of this study was to demonstrate the safety and effectiveness of a low-profile thoracic endograft (19-23 French) in subjects with blunt traumatic aortic injury. A prospective, multicenter study assessed the RelayPro thoracic endograft for the treatment of traumatic aortic injury. Fifty patients were enrolled at 16 centers in the United States between 2017 and 2021. The primary endpoint was 30-day all-cause mortality. The cohort was mostly male (74%), with a mean age of 42.4 ± 17.2 years, and treated for traumatic injuries (4% Grade 1, 8% Grade 2, 76% Grade 3, and 12% Grade 4) due to motor vehicle collision (80%). The proximal landing zone was proximal to the left subclavian artery in 42%, and access was primarily percutaneous (80%). Most (71%) were treated with a non-bare stent endograft. Technical success was 98% (one early type Ia endoleak). All-cause 30-day mortality was 2% (compared with an expected rate of 8%), with an exact two-sided 95% confidence interval [CI] of 0.1%, 10.6% below the performance goal upper limit of 25%. Kaplan-Meier analysis estimated freedom from all-cause mortality to be 98% at 30 days through 4 years (95% CI, 86.6%-99.7%). Kaplan-Meier estimated freedom from major adverse events, all-cause mortality, paralysis, and stroke, was 98.0% at 30 days and 95.8% from 6 months to 4 years (95% CI, 84.3%-98.9%). There were no strokes and one case of paraplegia (2%) during follow-up. RelayPro was safe and effective and may provide an early survival benefit in the treatment of blunt traumatic aortic injury. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the feasibility and outcomes of endovascular repair of thoracoabdominal aortic aneurysms (TAAAs) using a novel low profile (LP) device with upper extremity preloaded guidewire system (PGS) and compare procedural metrics and outcomes with a standard multibranch stent graft (t-Branch; Cook Medical, Bloomington, Ind). We reviewed the clinical data of 232 consecutive patients treated by fenestrated-branched endovascular aortic repair for TAAA and enrolled in a prospective nonrandomized trial between 2014 and 2017. Patients who had repair using t-Branch or patient-specific TAAA devices using upper extremity LP-PGS were included. End points were technical success, operative and fluoroscopic time, patient radiation exposure, time from arterial access to complete device deployment, total contrast volume, and 30-day rates of major adverse events (MAEs) and mortality. There were 54 patients, including 33 males (67%) and 21 females (33%), with a mean age of 73 ± 9 years old. Forty-nine patients (91%) had extent I-III and five patients (9%) had extent IV TAAAs. Device design was t-Branch in 24 patients (44%) and LP-PGS in 30 patients (56%). A total of 206 renal-mesenteric arteries were incorporated with no difference between groups (mean, 3.8 ± 0.6 target vessels/patient; P =.92). Patients treated by t-Branch device had larger mean aneurysm diameter (79 ± 16 vs 66 ± 10 mm; P =.0006). All patients had transbrachial approach. Technical success was achieved in all patients in both groups. Patients treated by LP-PGS devices had lower radiation dose (1250 ± 849 vs 3154 ± 2421 mGy; P =.003) and shorter operating time for complete device deployment (105 ± 42 vs 123 ± 34 minutes; P =.043). There was no difference in mean operative time (252 ± 69 vs 273 ± 56 minutes; P =.23), fluoroscopy time (82 ± 29 vs 96 ± 35 minutes; P =.08) or contrast volume (163 ± 59 vs 197 ± 75 mL; P =.07) comparing LP-PGS and t-Branch respectively. There was no 30-day or in-hospital mortality. There were no differences in MAEs, which occurred in 18 patients (33%) in both groups (P >.05). Endovascular TAAA repair using the standard or LP-PGS multibranch stent graft was associated with high technical success, no mortality, and a low rate of MAEs in this study. Patients treated by upper extremity LP-PGS had shorter time to complete device deployment, suggesting decreased technical demand with preloaded systems. [ABSTRACT FROM AUTHOR]

Aim: to evaluate the outcomes of EVAR performed with a new generation of bifurcated endografts and limbs. Methods: prospectively collected data from fifty consecutive patients with abdominal aortic aneurysms (AAA) treated at our institution with a Low Profile Zenith® bifurcated body/Zenith® Spiral-Z legs combo were analysed. AngioCT scans and Ultrasound exams were performed prior to discharge. Ultrasound examination was repeated 6 months after the procedure to assess endograft patency and to depict endoleaks Results: Median age was 70.6 years [50–88] and median ASA score was 3 [2–4]. Median aortic diameter was 56 mm [49–81]. Of the 100 external iliac access vessels, 14 had a diameter of 6 mm or lower. All endografts were successfully implanted. Post-operative Ultrasound examination and angioCT scan depicted both 1 type Ia, and 10 and 19 type 2 endoleaks respectively. An asymptomatic thrombosis of the left external iliac artery distal to the endograft limb was also depicted. 30-day mortality rate was 0%. Two patients died respectively three and four months after EVAR. Both deaths were not aneurysm related. All patients underwent an ultrasound exam 6–12 months after EVAR. All endografts main bodies and limbs were patent. Five endoleaks were depicted, all were type II endoleaks (the early type Ia endoleak had sealed spontaneously; it was confirmed by an angioCT scan). One patient presented a significant stenosis of the left iliac limb at the level of a narrow and calcified aortic bifurcation. It was successfully treated by bilateral iliac angioplasty and kissing balloon stenting. Conclusions: EVAR performed with the Zenith LP main body in combination with Spiral-Z Iliac Legs is safe and effective. No limb occlusions were diagnosed at the 6 month follow up even in challenging iliac anatomies usually considered as contra indications for EVAR. Our first results are most satisfying and calling to be completed by a longer follow up. [Copyright &y& Elsevier]

Reliable and efficient cooling solutions for portable electronic devices are now at the forefront of research due to consumer demand for manufacturers to downscale existing technologies. To achieve this, the power consumed has to be dissipated over smaller areas resulting in elevated heat fluxes. With regard to cooling such devices, the most popular choice is to integrate a fan driven heat sink, which for portable electronic devices must have a low profile. This paper presents an experimental investigation into such low profile cooling solutions, which incorporate one of the smallest commercially available fans in series with two different heat sink designs. The first of these is the conventionally used finned heat sink design, which was specifically optimized and custom manufactured in the current study to complement the driving fan. While the second design proposed is a novel "finless" type heat sink suitable for use in low profile applications. Together the driving fan and heat sinks combined were constrained to have a total footprint area of 465 mm² and a profile height of only 5 mm, making them ideal for use in portable electronics. The objective was to evaluate the performance of the proposed finless heat sink design against a conventional finned heat sink, and this was achieved by means of thermal resistance and overall heat transfer coefficient measurements. It was found that the proposed finless design proved to be the superior cooling solution when operating at low fan speeds, while at the maximum fan speed tested of 8000 rpm both provided similar performance. Particle image velocimetry measurements were used to detail the flow structures within each heat sink and highlighted methods, which could further optimize their performance. Also, these measurements along with corresponding global volume flow rate measurements were used to elucidate the enhanced heat transfer characteristics observed for the finless design. Overall, it is shown that the proposed finless type heat sink can provide superior performance compared with conventional finned designs when used in low profile applications. In addition a number of secondary benefits associated with such a design are highlighted including lower cost, lower mass, lower acoustics, and reduced fouling issues. [ABSTRACT FROM AUTHOR]

We present the 5-year results of a prospective regulatory study of the INCRAFT device, a low-profile endovascular stent graft system for repair of abdominal aortic aneurysms. This was an open-label prospective nonrandomized single-arm study enrolling in centers in the United States and Japan. The primary effectiveness outcome was successful aneurysm treatment and the primary safety outcome was the incidence of major adverse events at 30 days after the procedure. Major long-term outcomes were mortality, reintervention, adverse limb outcomes, and suprarenal stent fracture. One hundred and ninety patients (mean age, 73.8 ± 7.6 years; 90% male; 69% white and 30% Asian) were enrolled from 32 centers throughout the United States and Japan. Minimal access vessel size was less than 7 mm on both sides in 43.9% of the study cohort. Thirty-day major adverse events occurred in 3.2% of patients (6/190). Periprocedural technical success was 94.1% (176/187). Successful aneurysm treatment was 100% at 30 days and 87.9% at 1 year. Two patients required open conversion for thromboembolic complications, 3 developed new type I or III endoleaks, and 7 experienced graft or limb occlusion. Freedom from graft occlusion was 96 ± 2% at 1 year and 94 ± 2% at 5 years. Freedom from stent fracture was 97 ± 1% at 1 year and 87 ± 3% at 5 years. Freedom from aneurysm-related mortality was 99 ± 1% at 1 and 5 years. This study demonstrates good efficacy and safety and a very low rate of aneurysm related deaths with the INCRAFT device in a population with a high proportion of challenging anatomy. [ABSTRACT FROM AUTHOR]