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Background: This study investigated the impact of Chronic Low Back Pain (CLBP) on individuals' physical activity (PA) behaviours, specifically, how they modify, cease, or continue PA when experiencing CLBP. The primary aim was to explore the relationship between CLBP and PA and how this is influenced in different contexts (e.g., necessity of a task). Methods: A mixed‐methods survey was administered to 220 participants, including self‐reported outcomes, and capturing responses to three distinct questions related to PA and CLBP. The data was analysed via a content analysis. Results: The findings revealed that individuals with CLBP are most likely to modify PA in work‐related contexts and least likely to cease it in the same setting. Housework emerged as the most common domain for cessation of PA, while work/study activities were predominantly continued. Reasons for these trends were typically task‐based rather than health or enjoyment based and influenced by the perceived necessity of the task in question. Conclusion: The study highlights the role of occupational and educational settings in individual responses to CLBP. The findings also highlight a gap in public awareness regarding effective CLBP management strategies, emphasising the need for increased education and awareness programs. [ABSTRACT FROM AUTHOR]

Objective: To explore the effectiveness of a modified fear hierarchy on measuring improvements in movement‐associated fear in chronic low back pain. Methods: A modified 3‐item fear hierarchy was created and implemented based on principles of graded exposure. This study was an exploratory analysis of the modified 3‐item fear hierarchy from a larger clinical trial data set. Both groups received pain education and exercise, either bodyweight or strength training. Both groups performed item one on the hierarchy, the squat. Only the strength training group performed item 2, the deadlift. Neither group performed item 3, the overhead press. Analysis of Covariance and stepwise linear regression were used to explore results. Results: Improvement in movement‐associated fear was conditional upon graded exposure. Both groups improved in the squat movement (p ≤ 0.05), which both performed. Only the strength training group improved in the deadlift (p ≤ 0.01), and neither improved in the overhead press (p ≥ 0.05). Conclusion: Reductions in movement‐associated fear are conditional upon graded exposure, based on the use of a novel modified 3‐item fear hierarchy. Further research is needed to understand the utility of this tool in a patient‐led approach to co‐designing a graded exposure‐based intervention. [ABSTRACT FROM AUTHOR]

Experimental results are presented on proton induced single-event-upsets (SEU) on a 65 nm silicon-on-insulator (SOI) SRAM. The low energy proton SEU results are very different for the 65 nm SRAM as compared with SRAMs fabricated in previous technology generations. Specifically, no upset threshold is observed as the proton energy is decreased down to 1 MeV; and a sharp rise in the upset cross-section is observed below 1 MeV. The increase below 1 MeV is attributed to upsets caused by direct ionization from the low energy protons. The implications of the low energy proton upsets are discussed for space applications of 65 nm SRAMs; and the implications for radiation assurance testing are also discussed. Index Terms--Proton irradiation, silicon-on-insulator (SOI) technology, single event upset (SEU), SRAM.

This work presents 3-D mixed-mode simulation results of single event transients (SET) in SiGe HBT emitter followers. The impact of circuit design parameters, including biasing current and resistance are detailed. A simple increase of biasing emitter current is shown to be ineffective for hardening. Instead, during SET, the emitter voltage upset simply follows the base voltage upset due to the inherent nature of the emitter follower topology during circuit operation. The duration and the peak value of the base voltage upset are determined by the impedance and electric field between collector and base. As a result, the use of a smaller base biasing resistance is desirable for reducing SETs in emitter followers. Index Terms--Charge collection, heterojunction bipolar transistors, radiation hardening by design, single event effects, single event transients.

We report the first irradiation results on high-frequency SiGe HBT and CMOS phase shifters for space- based, phased-array antennas used in radar or wireless communication systems. Both phase shifter circuits remain functional with acceptable dc and RF performance up to multi-Mrad proton exposure, and are thus suitable for many orbital applications. In addition, simulation results probing the limits of phase shifter performance in a radiation environment are presented. These results show that both CMOS and SiGe HBT based phase shifters can be used for space-based applications without any specific radiation hardening techniques. Index Terms--CMOS, phased-array, phase-shifters, radar, radiation response, silicon-germanium HBT, single-pole double throw switch.

This paper presents the first comprehensive investigation of the impact of proton irradiation on the performance of high-voltage (HV) nMOS transistors implemented in a low-voltage (LV) SiGe BiCMOS technology. The effects of irradiation gate bias, irradiation substrate bias, and operating substrate bias on the radiation response of these transistors are examined. Experimental results show that the radiation-induced subthreshold leakage current under different irradiation biasing conditions remains negligible after exposure to a total dose of 600 krad(Si). We find that there are differences in the radiation response of LV and HV MOSFETs, suggesting that the mechanisms involved in causing degradation in LV and HV transistors could be of fundamentally different origins. Index Terms--High-voltage CMOS transistors, ionization damage, MOSFET, SiGe, total dose radiation effects.

We investigate radiation-induced effects on the DC, AC and thermal characteristics of high-performance SiGe HBTs fabricated on thin-film SOI. TCAD simulations indicate novel heavy-ion charge collection phenomena resulting from the unique [C.sub.B][E.sup.B]C device layout of this technology platform. Index Terms--C-SiGe, Heterojunction bipolar transistors, radiation effects, SiGe HBT, silicon-on-insulator (SOI), TCAD.

Device-level current transients are induced by injecting carriers using two-photon absorption from a subbandgap pulsed laser and recorded using wideband transmission and measurement equipment. These transients exhibit three distinct temporal trends that depend on laser pulse energy as well as the transverse and vertical charge generation location. The nature of the current transient is controlled by both the behavior of the subcollector-substrate junction and isolation biasing. However, substrate potential modulation, due to deformation of the subcollector-substrate depletion region, is the dominant mechanism affecting transient characteristics. Index Terms--Current transient, electrostatic potential modulation, SiGe HBT, two-photon absorption.

Microbeam measurements and TCAD simulations are used to examine the effects of ion angle of incidence on the charge collected from events occurring in a Silicon Germanium (SiGe) Heterojunction Bipolar Transistor (HBT). The results identify the geometrically driven charge-collection mechanisms that dominate the low LET broad beam SEU response. The deep trench isolation that surrounds the transistor significantly modulates the charge transport and, therefore, the charge collected by the collector. A new way of estimating critical charge, [Q.sub.crit], for upset in SiGe HBT circuits is proposed based on TCAD simulation results and measured broadbeam data. Index Terms--Deep trench isolation (DTI), HBT, IBICC, silicon germanium (SiGe), single event upset (SEU), TCAD.