Standard Devices Research Articles

Feasibility and performance evaluation of low-cost GNSS devices for sea level measurement based on GNSS-IR

The low-cost GNSS devices are more convenient, flexible, and can be used as the low-cost Global Navigation Satellite System interferometric reflectometry (GNSS-IR) sensors. In this study, the feasibility and performance of low-cost GNSS devices for the temporary sea level measurement are assessed, by jointly utilizing signal-to-noise ratio (SNR) data from an Android smartphone Redmi Note 9 Pro and a low-cost antenna BT560 connected to a CHCNAV P5 GNSS receiver, while another identical receiver equipped with a standard geodetic-quality antenna and a pressure tide gauge (TG) were placed nearby for comparison. 80-hours of SNR data from multiple GNSS constellations were collected and processed. First, the SNR data from the three devices are compared and analyzed. In most cases, the SNR data of low-cost antennas have longer and clearer oscillations. But they are maybe more vulnerable due to the manufacturing of antennas or positioning modules. Second, quality control and height rate correction are crucial to stable sea level measurement of low-cost GNSS devices. Finally, the performance of sea level measurement of multiple GNSS constellations, dual-frequency, and dual-antenna was also assessed. It is found that the low-cost GNSS devices could yield stable sea level measurements, and have a root-mean-square error (RMSE) of about 16 cm, of which the performance is equivalent to or even slightly better than standard geodetic-quality devices, making it a promising solution for the temporary TGs.

Tumor location on electroporation therapies by means of multi-electrode structures and machine learning

Electroporation is a phenomenon produced in the cell membrane when it is exposed to high pulsed electric fields that increases its permeability. Among other application fields, this phenomenon can be exploited in a clinical environment for tumor ablation therapies. In this context to achieve optimum results, it is convenient to focus the treatment on the tumor tissue to minimize side effects. In this work, a pre-treatment tumor location method is developed, with the purpose of being able to precisely target the therapy. This is done by taking different impedance measurements with a multi-output electroporation generator in conjunction with a multi-electrode structure. Data are processed by means of a vector of independent artificial neural networks, trained and tested with simulation data, and validated with phantom gels. This algorithm proved to provide suitable accuracy in spite of the low electrode count compared to the number of electrodes of a standard electrical impedance tomography device.

Contactless and Longitudinal Monitoring of Nocturnal Sleep and Daytime Naps in Older Men and Women: A Digital Health Technology Evaluation Study.

To compare the 24-hour sleep assessment capabilities of two contactless sleep technologies (CSTs) to actigraphy in community-dwelling older adults. We collected 7 to 14 days of data at home from 35 older adults (age: 65-83), some with medical conditions, using Withings Sleep Analyser (WSA, n=29), Emfit-QS (Emfit, n=17), a standard actigraphy device (Actiwatch Spectrum [AWS, n=34]) and a sleep diary. We compared nocturnal and daytime sleep measures estimated by the CSTs and actigraphy without sleep diary information (AWS-A) against sleep diary assisted actigraphy (AWS|SD). Compared to sleep diary, both CSTs accurately determined the timing of nocturnal sleep (ICC: going to bed, getting out of bed, time in bed > 0.75) whereas the accuracy of AWS-A was much lower. Compared to AWS|SD, the CSTs overestimated nocturnal total sleep time (WSA: +92.71±81.16min; Emfit: +101.47±75.95min) as did AWS-A (+46.95±67.26min). The CSTs overestimated sleep efficiency (WSA: +9.19±14.26 %; Emfit: +9.41±11.05 %) whereas AWS-A estimate (-2.38±10.06 %) was accurate. About 65% (n=23) of participants reported daytime naps either in-bed or elsewhere. About 90% in-bed nap periods were accurately determined by WSA while Emfit was less accurate. All three devices estimated 24-h sleep duration with an error of ≈10% compared to the sleep diary. CSTs accurately capture the timing of in-bed nocturnal sleep periods without the need for sleep diary information. However, improvements are needed in assessing parameters such as total sleep time, sleep efficiency and naps before these CSTs can be fully utilized in field settings.

A standard descriptor for fixed-target serial crystallography.

Fixed-target crystallography has become a widely used approach for serial crystallography at both synchrotron and X-ray free-electron laser (XFEL) sources. A plethora of fixed targets have been developed at different facilities and by various manufacturers, with different characteristics and dimensions and with little or no emphasis on standardization. These many fixed targets have good reasons for their design, shapes, fabrication materials and the presence or absence of apertures and fiducials, reflecting the diversity of serial experiments. Given this, it would be a Sisyphean task to design and manufacture a new standard fixed target that would satisfy all possible experimental configurations. Therefore, a simple standardized descriptor to fully describe fixed targets is proposed rather than a standardized device. This descriptor is a dictionary that could be read by fixed-target beamline software and straightforwardly allow data collection from fixed targets new to that beamline. The descriptor would therefore allow a much easier exchange of fixed targets between sources and facilitate the uptake of new fixed targets, benefiting beamlines, users and manufacturers. This descriptor was first presented at, and was developed following, a meeting of representatives from multiple synchrotron and XFEL sources in Hamburg in January 2023.

Fetal Health Assessment Through Remote Fetal Phonocardiography and Electrohysterography: Wearable Wireless Device Using Shakti Processor

Pregnant women and neonates are the most affected demographic group by the shortfall of accessible healthcare. In this work, we aimed to improve obstetric facilities in rural India by proposing a remote maternal health monitoring device in which pregnant women can avail healthcare services without long-distance travel. We designed and developed a prototype of the proposed device using the open-source Shakti processor to provide remote real-time monitoring of the fetal heart rate and uterine contractions for the detection of any abnormalities. Fetal phonocardiography signal was picked up using an acoustic sensor while the electrohysterography signal was acquired using surface electrodes placed on a pregnant woman. The placement of the sensor and electrodes was referred by an obstetrician. The system was placed on 10 pregnant women in their last trimester with their informed consent and the monitored parameters were validated by a clinician. The obtained fetal heart rate and uterine contractions were compared with that from standard clinical devices and the results from the proposed device were observed to be comparable with that of the standard devices.

Improving stability and efficiency of three-dimensional perovskite solar cells with organophosphorus ligands

The core density of the defects in perovskite thin films will directly affect the properties of perovskite solar cells. On the other hand, interface engineering is usually being used to effectively improve the quality of perovskite thin films. In this sought of work, MAPbI3 perovskite thin films were modified by an antisolvent process using trioctylphosphine as a passivator. Trioctylphosphine is a kind of Lewis base and from the experimental results, it is noticed on being contribute to MAPbI3 grain growth and grain boundary passivation. Due to the grain boundary passivation and grain size increase, the intense defect density inside the grain and at the grain boundary of the MAPbI3 films is gradually reduced, thereby improving the carrier lifetime, while the hydrophobic property of octyl alkane makes the perovskite thin films less susceptible to air, water and oxygen degraded by the influence. The solar cell which are using the proposed films with the device structure configuration as ITO/SnO2/MAPbI3/spiro-OMeTAD/Ag and the perovskite layers were modified with trioctylphosphine. Among them, the perovskite thin films showcased to have a best performance when the trioctylphosphine chlorobenzene solution was about 0.15% and the PCE of the device reached for about 12.17%, an increase of 10% was compared with the standard device. In addition, the modified device exhibits good environmental stability, retaining about 90% of the initial efficiency for 100 h in a 70% humidity environment.

Comparison of Heat Sinks in Back-End of Line to reduce Self-Heating in 22FDX® MOSFETs

This work compares the effect of different heat sink dimensions in the back-end of line (BEOL) on the self-heating (SH) parameters. To assess the self-heating (SH) parameters, the RF characterization technique is employed, which involves measuring S-parameters across a broad frequency spectrum. In addition to the standard device without a sink, two sinks of different dimensions, both connected to the gate, are considered: one smaller and one bigger in size. We experimentally demonstrate lower self-heating as the sink size increases. By using a smaller and a larger sink, a mean reduction of 4.7% and 8.9% in thermal resistance is observed, showing greater SH reduction with increasing sink size, which is also verified from comparison with previous works. The impact of the sinks on RF figures-of-merit (FoMs), namely the cutoff frequency fT and maximum oscillation frequency fmax is investigated. fT is seen to degrade stronger due to increased gate capacitance whereas fmax degradation is limited because of reduced gate resistance.

Design And Development Of Spo2, Bpm, And Body Temperature For Monitoring Patient Conditions In Iot-Based Special Isolation Rooms

The use of batteries as the main power source in portable equipment systems has several drawbacks, including the percentage of battery power that must be monitored so that the system is always active. Analysis of battery power efficiency is needed to determine the resistance of portable systems. This study makes a portable system for monitoring the condition of patients with infectious diseases in a special isolation room that can measure heart rate, body temperature, and oxygen saturation. The design of this device uses a 2200mAH battery as a power source on the IC TTGO ESP32 to manage data and display measurement results, the MAX30102 sensor to measure oxygen saturation and heart rate, and the MCP9808 sensor to measure body temperature. The design of this device has been tested on respondents aged 25-40 years by placing the sensor on the fingertip then the measurement results are compared with a standard device that has been calibrated. The measurement results show that the device is feasible to use because the measurement error value is ±5%. Testing the efficiency of battery power in normal mode and save mode. In normal mode, the current used in the device is 154.9 mA, while the save mode by not activating the LCD TTGO ESP32 requires a current of 126.7 mA. The results of the analysis show that using the battery in normal mode can activate the device for up to ±14 hours and in save mode for ±17 hours. This designed method is useful for measuring power efficiency in different device modes and the user knows the battery charging time at regular intervals.

Accuracy of wearable electronic device compared to manual and automatic methods of blood pressure determination.

Blood pressure (BP) is the main biomarker for monitoring patients, as its lack of control above values considered normal is a modifiable risk factor for target organ damage. The aim of this study is to evaluate the accuracy of the wearable electronic device photoplethysmography technology (PPG) Samsung Galaxy Watch 4 in determining BP in young patients compared to manual and automatic methods of BP determination. This is a quantitative and cross-sectional study, following validation protocols for wearable devices and BP measurement. It was carried out with twenty healthy young adults, in which BP was measured using four instruments, namely, standard sphygmomanometer device (manual), automatic arm oscillometric device (reference), wrist oscillometric device, and Smartwatch PPG. Eighty systolic blood pressure (SBP) and diastolic blood pressure (DBP) readings were observed. SBP means manual 118 ± 2.20,arm 113 ± 2.54, wrist 118 ± 2.51, and PPG (smartwatch) 113 ± 2.58. Among means, arm and PPG difference is 0.15, arm and wrist 4.95, arm and manual 4.45 wrist with PPG. The mean DBP manual 76.7 ± 1.84, arm 73.6 ± 1.92, wrist 79.3 ± 1.87, and PPG 72.2 ± 1.38. Among means, the difference between the arm and PPG is 1.4 and arm and hand 3.5mmHg. The correlation shows PPG with manual, arm, and wrist. There was a strong SBP correlation and a moderate DBP correlation between the methods tested, evidencing the accuracy of the PPG smartwatch in relation to the reference method.

Multidetector Computed Tomographic Evaluation of Hydrocephalus

Introduction: Hydrocephalus is characterized by imbalance of cerebrospinal fluid formation and absorption. It is manifested as a dilatation of the ventricular system. Computed tomography (CT) is useful in determining the ventricular size and shape as well as the amount of the cerebral cortex present in the evaluation of suspected hydrocephalus. Aim and Objectives: Detection of hydrocephalus and determining the cause of hydrocephalus. Differentiating communicating from noncommunicating (obstructive) hydrocephalus. to assess the severity of the hydrocephalus and seek for any consequences. Materials and Methods: This prospective study included 50 patients referred to the Acharya Vinoba Bhave Rural Hospital, Sawangi (Meghe), Wardha, for 1 year. Patients clinically diagnosed with hydrocephalus were included in the study. Multidetector CT (MDCT) imaging was performed on Siemens 16 Slice MDCT machine. Multiplanar reformation and three-dimensional reconstruction were done wherever necessary. Results: 20% were diagnosed to have meningitis, 10% had Intraparenchymal haemorrhage and Intraventricular extension, 12% had aqueduct stenosis, and 12% had communicating hydrocephalus. In the study, 40% of them had communicating-type hydrocephalus or extraventricular obstructive hydrocephalus and 60% had obstructive hydrocephalus. On the CT scan, it was observed that at the lateral ventricle, dilatation was observed in four regions. Frontal horn dilatation (98%), body dilatation (98%), and 100% dilatation were seen at the temporal horn and occipital horn. Among 100 patients, 14% had cortical thinning and thus were classified as severe hydrocephalus with a poor prognosis, and 20% had periventricular edema. Conclusion: CT is the best means of obtaining images as it is easily available, fast, reliable, and compatible with standard life support devices.

The improvement of operational properties of the parts of means of transport by applying regular reliefs

Problem. Specially created regular surface reliefs strongly influence the reliability and operational properties of machine parts. One of the effective methods of obtaining reliefs is cold plastic deformation (CPD). This method of modification does not lead to the occurrence of significant stresses in the material of the part and can be form-forming. The latter is important in repair production. However, to date, there is no systematic study of the formation of reliefs by CPD methods, especially with the use of linear indenters. Goal. To improve the operational properties of the parts of means of transport by applying regular micro- and macro-reliefs of technological and operational purposes by deepening linear indenters. Methodology. Press hydroficated equipment was used to create a normal indenter penetration force. The brands of typical structural materials are defined: steel, gray cast iron, bronze, brass, aluminum and titanium alloys. A linear indenter made of high-speed steel with angles at the top of 60° - 90° and a radius at the base of 0.005 - 0.5 mm was created. Methods of microstructural analysis and microhardness, standard and original instruments and devices were used. The range of groove depths was 0.02-0.5 mm. A lubricating-cooling liquid based on rapeseed oil was used. Results. It was hypothesized that when the indenter is immersed in the material of the part, the factors that have the greatest influence on the depth and other parameters of the relief groove are the normal strength, hardness, and relative elongation of the material under study. These theoretical principles formed the basis of the mathematical model of the indentation process. Originality. It was created a classification of regular reliefs by purpose: for preliminary division of the allowance during cutting; for preparing the surfaces of parts for applying coatings, including anti-friction films; to create labyrinths on the surface of parts for lubricants; for preliminary separation of fragmentary ammunition cases; to create strengthened new load-bearing surfaces, in particular, discrete when restoring worn parts; to obtain complex profiles on the surfaces of the holes of the parts. The calculation of the impact of the indentation force and the geometric parameters of the linear indenter on the shape and dimensions of the relief groove has been developed. Theoretical propositions about the influence of the embedment force, hardness and plasticity of the material of the part on the parameters of the relief groove were experimentally confirmed. These factors affect the optimization parameter both directly and through intermediate factors: the radius of rounding and the angle at the top of the indenter and the composition of the lubricating and cooling liquid and the speed of immersion. The interrelationship of phenomena during the formation of reliefs and the dependence of the depth of the groove on the process factors are constructed. Practical value. The method of restoring worn parts by indenting a linear indenter was developed, the principle of obtaining discrete surfaces of machine parts by alternating relief grooves with flat areas within a discreteness of 5-50% and methods of obtaining shaped surfaces in the holes of hollow parts by copying were developed.

Sterilization and reuse of masks for a standardized exhaled breath collection device by autoclaving

Exhaled breath research has been hindered by a lack of standardization in collection and analysis methodologies. Recently, the Respiration Collector for In Vitro Analysis (ReCIVA) sampling device has illustrated the potential to provide a consistent and convenient method for exhaled breath collection onto adsorbent media. However, the significant costs, compared to exhaled breath bags, associated with the standardized collector is believed to be the reason for limited widespread use by researchers in the exhaled breath field. For example, in addition to the sampling hardware, a single-use disposable silicon mask affixed with a filter is required for each exhaled breath collection. To reduce the financial burden, streamline device upkeep, reduce waste material, and ease the logistical burden associated with the single use masks, it is hypothesized that the consumable masks and filters could be sterilized by autoclaving for reuse. The masks were contaminated, autoclaved, and then tested for any surviving pathogens with spore strip standards and by measuring the optical density of cultures. The compound background collected when using the ReCIVA with new masks was compared to that collected with repeatedly autoclaved masks via thermal desorption gas chromatography mass spectrometry (TD-GC-MS). The capacity to block particulate matter of new filters was tested against that of autoclaved filters by introducing an aerosol and comparing pre-filter and post-filter particle counts. Finally, breath samplings were conducted with new masks and autoclaved masks to test for changes in measurements by TD-GC-MS of exogenous and endogenous compounds. The data illustrate the autoclave cycle sterilizes masks spiked with saliva to background levels (p = 0.2527). The results indicate that background levels of siloxane compounds are increased as masks are repetitively autoclaved. The data show that mask filters have significant breakthrough of 1 μm particles after five repetitive autoclaving cycles compared to new filters (p = 0.0219). Finally, exhaled breath results utilizing a peppermint ingestion protocol indicate two compounds associated with peppermint, menthone and 1-Methyl-4-(1-methylethyl)-cyclohexanol, and an endogenous exhaled breath compound, isoprene, show no significant difference if sampled with a new mask or a mask autoclaved five times (p > 0.1063). Collectively, the data indicate that ReCIVA masks and filters can be sterilized via autoclave and reused. The results suggest ReCIVA mask and filter reuse should be limited to three times to limit potentially problematic background contaminants and filter dysfunction.

A Novel Method for Angioscopic Imaging and Visualizing the Skull Base Using Complementary Metal Oxide Semiconductor Cameras.

Complementary metal oxide semiconductor (CMOS) electrode arrays are a novel technology for miniaturized endoscopes; however, its use for neurointervention is yet to be investigated. In this proof-of-concept study, we aimed to demonstrate the feasibility of CMOS endoscopes in a canine model by providing direct visualization of the endothelial surface, deploying stents and coils, and accessing the spinal subdural space and skull base. Using 3 canine models, standard guide catheters were introduced into the internal carotid and vertebral arteries through the transfemoral route using fluoroscopy. A 1.2-mm CMOS camera was delivered through the guide catheter to inspect the endothelium. Next, the camera was introduced alongside standard neuroendovascular devices including coils and stents to provide direct visualization of their deployment within the endothelium during fluoroscopy. One canine was used for skull base and extravascular visualization. A lumbar laminectomy was performed, and the camera was navigated within the spinal subdural space until the posterior circulation intracranial vasculature was visualized. We successfully visualized the endothelial surface and performed several endovascular procedures such as deployment of coils and stents under direct endovascular, angioscopic vision. We also demonstrated a proof of concept for accessing the skull base and posterior cerebral vasculature using CMOS cameras through the spinal subdural space. This proof-of-concept study demonstrates the feasibility of CMOS camera technology to directly visualize endothelium, perform common neuroendovascular procedures, and access the base of the skull in a canine model.

Effects of 3D-printed assistive device on daily life function in patients with neurological impairment: a pilot study

Purpose To explore the effects of customized 3D-printed assistive technology (AT) on functional performance and feasibility in patients with neurological impairment. Methods Patients with neurological impairment were recruited and randomized into customized 3D-printed assistive device group (group 1; n = 17) or standard device group (group 2; n = 14). The device was designed to assist their writing, spoon using, and typing. Each patient underwent 4-week intervention with the device (30 min per session, twice a week). Results We observed significant differences in shoulder abduction (p = .00), external rotation (p = .01), and internal rotation (p = .02) in group 1. And significant differences in abduction (p = .05) and external rotation (p = .05) between the 2 groups. Group 1 achieved significant improvements in writing without AT (p = .04) and with AT (p = .02), spoon use without AT (p = .02) and with AT (p = .03), and hemiplegia-side typing with AT (p = .00). Group 2 achieved significant improvements in writing without AT (p = .01), hemiplegia-side typing without AT (p = .01), and bil-side typing with AT (P = .05). Moreover, no significant differences were noted in other outcome measures. Conclusions This study demonstrated that customized 3D-printed AT can improve shoulder active motion for patients with neurological impairment. A positive effect in functional hand tasks after AT intervention. Offering customized AT with specific training could enhance the efficacy of interventions. The feasibility of using 3D printing technology to produce customized AT, which has the potential to be cost-effective and efficient.

A new alignment device for standardization of marker placement on the hindfoot

BackgroundFor multi-segment foot models, next to a (dorsal) heel marker, further markers are typically placed medially (MCL) and laterally (LCL) on the calcaneus. However, there is a lack of easily identifiable landmarks on the hindfoot limiting the repeatability of measurements. For a more consistent placement of these markers, an improved Hindfoot Alignment Device (HiAD) was developed. MethodsWith the HiAD, the position of the MCL and LCL can be individually scaled. Flexible bars allow the adaptation to foot deformities. Three rater placed markers with the HiAD four times on ten typical developed subjects (20 feet). Rigid segment residuals of the hindfoot were calculated and compared with the residuals when using the device of Simon et al. (2006) [12]. The variability of the placement of MCL, LCL and the clinical parameter medial arch were determined. For assessing the inter- and intra-rater reliability, intraclass correlation coefficient (ICC) and the standard error of measurement (SEM) were calculated. ResultsRigid segment residuals of the hindfoot could be reduced by 70 % by using the HiAD. Largest inter-rater variability in the MCL and LCL placement was found in z-direction with less than 3.2 ± 2.7 mm and 3.8 ± 2.8 mm, respectively. Correspondingly, largest intra-rater variability was 3.4 ± 2.3 mm for LCL and 2.4 ± 1.9 mm for MCL, respectively. Regarding reliability ICC showed good to excellent results for the medial arch (interrater ICC 0.471–0.811). SignificanceThe application of HiAD to place MCL and LCL appear to be a reliable method with robust marker positions and could be implemented in any multi segment foot model. However, further investigation would be helpful to determine the sensitivity of the marker positions in detecting hindfoot deformities.

#2984 ACHIEVED BLOOD PRESSURE AND CARDIOVASCULAR OUTCOMES IN PATIENTS WITH ADVANCED STAGE CHRONIC KIDNEY DISEASE

Abstract Background and Aims In patients with severely decreased eGFR (stage 4-5 CKD), efficacy of treating patients to a lower blood pressure (BP) target is uncertain. The Systolic blood PRessure INtervention Trial (SPRINT) demonstrated lower rates of a composite cardiovascular (CVD) endpoint and death in the intensive treatment group with a target systolic blood pressure (SBP) of <120 mmHg. This study has influenced guidelines; the updated 2021 Kidney Disease Improving Global Outcomes (KDIGO) now suggest lowering the SBP to < 120 mmHg, if tolerated. In this study we set out to investigate the association between SBP and CVD in a large cohort of nephrology-referred patients with CKD stage 3-5. Method We included patients ≥18 years participating in the Swedish Renal Registry (SRR-CKD) who had a first registered eGFR <60 ml/min/1.73 m2 2006-2017 with at least one recorded BP measurement and two out-patient visits within one year. We excluded individuals with a recorded SBP <100 mmHg or prior kidney failure replacement treatment. After the initial one-year observation period, we followed patients until the primary or secondary outcome was attained, or until December 31, 2017. The achieved average systolic BP, measured during routine out-patient care using any standard electronic or manual blood pressure device, was categorized into a priori defined categories. To align with SPRINT, the primary endpoint was Major Cardiovascular Events (MACE) defined as the composite of first myocardial infarction (MI), non-MI acute coronary syndrome, stroke, heart failure, or death attributable to CVD. The secondary endpoints were the individual components of the primary composite endpoint, all-cause death, or a composite of the primary endpoint and death. Demographics, body mass index, underlying kidney disease, and laboratory values at the start of follow-up were obtained from the SRR-CKD. Information on comorbidity, including Charlson comorbidity index was gathered from a linkage with the National Patient Registry; medications were obtained from the National Prescribed drug register. The primary endpoint and secondary endpoints were assessed by cause-specific Cox proportional hazards regression, adjusting for age, sex, history of CVD, Charlson comorbidity, plasma albumin, phosphate, diuretics, RAASi, betablockers, eGFR, and diastolic blood pressure. Missing data were handled through multiple imputation. Results In total 15,668 patients with a median eGFR 23 ml/min/1.73 m2, mean age 71 years and 33% women were followed over a period of 2.8 years (IQR 1.4-5.0). There were 6359 patients (41%) experiencing the primary outcome; 2601 (17%) with a coronary artery event, 1427 (9%) MI, 1,345 (9%) cerebrovascular event, and 5,480 (35%) patients died. The unadjusted analysis showed a J-shaped relationship between SBP and the primary outcome, with the lowest risk of events in patients with SBP around 125 mmHg (Figure 1). In multivariable models, there was a higher risk of experiencing the primary outcome if the average SBP was >150 mmHg (HR 1.09;95%CI 1.0-1.19), the highest risk being in those with SBP above 160 mmHg (HR 1.40 with 95% CI 1.28-1.53) as compared to those with SBP 130-140 mmHg (Figure 2). We observed 30% lower risk of MI when the SBP was 100–120 mmHg after adjustments (HR 0.70 (95% CI 0.56–0.88) as compared to 130–140, and higher risk of MI at SBP >160 mmHg (1.78; 1.49–2.12) with 11% higher risk of MI with every 10 mmHg increase in SBP (HR 1.11; 1.07–1.14). The other cardiovascular endpoints, including all-cause mortality showed a similar pattern as the primary composite endpoint. Conclusion In patients with advanced stage CKD, SBP <120 mmHg is associated with lower risk of MI, but not with lower risk of other cardiovascular outcomes or all-cause mortality. A SBP >140 mmHg was associated with higher risk of most cardiovascular events including cardiovascular mortality and all-cause mortality.

#6031 ASSOCIATION BETWEEN THE MINI-BESTEST AND POSTUROGRAPHY IN PATIENTS ON HEMODIALYSIS

Abstract Background and Aims Patients on hemodialysis present complications due chronic kidney disease and hemodialysis treatment that compromise postural balance. Posturography is the gold standard device for measuring postural balance; however, its cost limits the use of this method for routine patient evaluation. Alternatively, the Mini Balance Evaluation Systems Test (Mini-BESTest) have been used to evaluate postural balance, as it is inexpensive and has high test-retest reliability. Therefore, the aim of this study was to evaluate the association between the Mini-BESTest and posturography in patients on hemodialysis. Method A cross-sectional study was conducted with patients aged ≥18 years who were undergoing hemodialysis treatment for at least three months. Patients were excluded if presented physical or cognitive incapable to perform the proposed tests, assisted gait, uncorrected visual impairments, severe and unstable comorbidities, and hospitalization in the past three months. Postural balance was evaluated by the Mini-BESTest and posturography [a force plate recorded the center of pressure (COP) path length in a static position with eyes opened (EO) and eyes closed (EC) on a firm surface]. The normality of the data was analyzed using the Shapiro‒Wilk test. The associations between Mini-BESTest score and COP path length in the EO and EC were tested using Spearman´s correlation coefficients. Then, two multiple linear regression models were constructed with COP path length in the EO and EC as the dependent variable and Mini-BESTest score and potential confounders (age, gender, diabetes mellitus, body index mass, hemodialysis efficiency index, and hemoglobin) as independent variables. A p value <0.05 was considered as statistically significant. Results This study included 109 patients (58.4 ± 12.9 years, 57.8% male). The Mini-BESTest was correlated with COP path length in the EO (ρ = -0.365, p < 0.001) and EC (ρ = -0.279, p = 0.003). The multiple linear regression models showed an association of the Mini-BESTest with COP path length in the EO (R2 = 0.28; adjusted R2 = 0.23; p < 0.001) and EC (R2 = 0.26; adjusted R2 = 0.20; p < 0.001). Conclusion The Mini-BESTest was associated with posturography in patients on hemodialysis. Therefore, the Mini-BESTest is a feasible test to evaluate postural balance in clinical routine practice during the physical function evaluation of these patients.

Recent developments in absolute dosimetry for FLASH radiotherapy.

Ultra-high dose-rate (UHDR) irradiations, known as FLASH radiotherapy (RT), rely on delivery of therapeutic doses at instantaneous dose-rates several orders of magnitude higher than those currently used in conventional radiotherapy. It has been shown that such an extremely short delivery of radiation leads to remarkable reduction of normal tissue toxicity with respect to conventional dose-rate RT. However, dosimetry at UHDRs is complicated and it is essential to understand the effects that will influence detector response. To date, FLASH RT research has been focused on finding pragmatic solutions that allow the use of UHDR beams in the research setting, but there has been limited focus on absolute dosimetry utilizing primary and secondary standard devices. However, very recently, the data on existing standard dosimeters and novel solutions which could serve as secondary standard devices in UHDR dosimetry started emerging. This review provides an overview of the studies that have been conducted employing calorimeters and innovative solutions utilizing ionization chambers.

650V Vertical SiC MOSFETs and Diodes with Improved Terrestrial-Neutron Single-Event Burnout

Silicon carbide (SiC) power devices such as Schottky diodes and metal-oxide semiconductor field-effect transistors (MOSFETs) are susceptible to failure by terrestrial neutron single-event burnout (SEB) while in the high-voltage blocking state. In this study the effects of the drift layer design of 650V SiC vertical power diodes and MOSFETs have been studied. TCAD simulations of different device designs have been performed, and fabricated device single-event burnout (SEB) properties are compared between the devices fabricated. We find that the standard 650V devices have a low area-scaled failure-in-time (FIT/cm2) such that essentially no failures (0.01 FIT/cm2) are expected at 400V drain-source bias (VDS) operation and below. An improved design allows the SEB failure rate curve to be shifted downward in failure rate, such that at for a given VDS operation condition, the FIT/cm2 can be decreased by 10 - 100 times, depending on the VDS value. This allows operation at about 75V higher VDS value with a similar SEB failure rate, allowing these devices to be used in a wider range of applications.

Reliability Enhancement by Doping Boron and Fluorine in Lightly Doped Drain Region of High-Voltage FinFET

<italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">This study focuses on the influence of boron doping in FinFET Lightly Doped Drain (LDD) region. By modulating the concentration of boron, the maximum of electric field can be reduced to improve the reliability in hot carrier stress (HCS), while the initial electric characteristics of boron doped devices do not change a lot, compared with those of the standard (STD) device. Even though Boron doping may cause slight decreases in transconductance (gm) and Ion, but it can effectively improve the reliability of the device. The reduction of the electric field affected by boron is demonstrated in the simulation. Careful adjustment is needed to prevent the maximum of the electric field from shifting to the other side of LDD and causing the rise of the electric field rise. In this study, the electric characteristic of LDD boron doping in FinFET structure is comprehensively analyzed.</i>