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Background: The purpose of study was to analyze correlations between bony torsions measured by Staheli's rotation profile, computed tomography (CT) torsional study, and gait analysis in patients with cerebral palsy (CP).Materials& Method: The study group comprised of 26 children with CP (spastic diplegia, Gross Motor Function Classification System (GMFCS) 1-2, mean age 12.6 years) with torsional deformities. All subjects were assessed by examining: 1) rotational profile [internal rotation (IR) and external rotation (ER)], 2) CT torsional profile [femoral anteversion (FAV) and tibial torsion (TT)], and 3) gait analysis [mean hip rotation (HR) and mean knee rotation (KR)]. Statistical analysis was performed using the Pearson correlation test.Results: In the femur, there was good correlation between FAV and Staheli's rotational profile of IR and ER (Pearson correlation coefficient (PC=0.69, 0.52, p<0.05)). ER correlated very strongly with mean HR during gait (PC=0.8, p<0.05). There was, however, poor correlation between HR and IR (p>0.05), and between HR and FAV (p>0.05). In the tibia, mean KR correlated well with thigh-foot angle (TFA) (PC=0.72) and CT tibia torsion (TT) (PC=0.62). TT also correlated with TFA (PC=0.62).Conclusion: Gait analysis and Staheli's rotational profile reflect both static and dynamic factors of gait abnormalities. However, CT study reflect static factor primarily. Dynamic factors tend to influence the measurements of the femoral torsion only due to large rotational arc of hip joint. In surgical planning, it must be considered that HR sometimes does not correlate with CT anteversion angle. Similarly, it must also be considered that KR correlates well with TFA and CT TT angle. [ABSTRACT FROM AUTHOR]

In order to understand the effect of temperature on slug properties, the onset velocity of slugging, slug rising velocity and slug frequency have been measured by a differential pressure method in an electrically heated gas fluidized bed of 0.1 m i.d. and height of 1.97 m and, with respect to variations in gas velocity (Umf∼0.15 m/s) and temperature (25–400 °C). Air was used as fluidizing gas and fluid catalytic cracking (FCC) catalyst particle (Geldart''s group-A particle, dp=0.071 mm, ρp=1600 kg/m3) as bed material. The minimum slugging velocity was found to increase a little with bed temperature. The qualitative change in minimum slugging velocity was found to agree with the inverse of minimum fluidizing velocity as temperature was varied. As the bed temperature increased, slug frequency was found to decrease a little, whereas slug rising velocity increased. A correlation between slug rising velocity and bed temperature was proposed. [Copyright &y& Elsevier]

Alicea, SK, Parrott, AD, Manos, TM, and Kwon, YS. Comparison of the affective responses to continuous training and high-intensity interval training protocols: application of the dual-mode model. J Strength Cond Res 35(11): 3069–3075, 2021—High-intensity interval training (HIIT) is time-efficient and has physiological benefits similar to or greater than that of continuous training (CT); however, there are mixed results regarding how HIIT protocols influence affect. The purpose of this study was to compare acute affective responses between HIIT and CT protocols over time using the Dual-Mode Model (DMM) as a theoretical framework. Subjects included 12 healthy women (aged 19–28 years) who completed a HIIT protocol consisting of a 2-minute work interval (100% V̇ o 2max) followed by a 2-minute rest interval (∼55% V̇ o 2max), and a CT protocol set at the workrate corresponding to their respiratory compensation point (RCP; ∼80% V̇ o 2max). Protocols were matched for average intensity, total duration, and energy expenditure. After blood pressure, anthropometrics, body composition, and V̇ o 2max measurements were taken, responses were recorded for affect (Feeling Scale [FS]), arousal (Felt Arousal Scale [FAS]), and rate of perceived exertion (RPE) before each protocol, during the last 10 seconds of every 2 minutes during the protocol, and at time points 2, 5, and 10 minutes after the protocol. Heart rate was also monitored continuously, and exercise enjoyment was measured before and after exercise. A repeated-measures analysis of variance revealed no significant differences in affect between CT (M = 2.5, SD = 2.1) and HIIT (M = 2.6, SD = 2.1) protocols over the duration of the exercise. There were no significant differences in mean RPE between CT (M = 12.9, SD = 2.7) and HIIT (M = 13.0, SD = 1.9) protocols (t = 0.333, p = 0.745) or in enjoyment between CT (M = 2.3, SD = 1.1) and HIIT (M = 2.0, SD = 0.9) protocols (t = −0.288, p = 0.492). In addition, based on visual inspection, the general patterning of the mean FS and FAS values between HIIT and CT was similar within the circumplex model, supporting the DMM. In conclusion, a HIIT protocol at V̇ o 2max and 1:1 exercise:rest interval did not result in a different affect response, perceived exertion, or enjoyment level when compared with a CT protocol at RCP. [ABSTRACT FROM AUTHOR]

Hernandez, DJ, Healy, S, Giacomini, ML, and Kwon, YS. Effect of rest interval duration on the volume completed during a high-intensity bench press exercise. J Strength Cond Res 35(11): 2981–2987, 2021—Between-set rest intervals (RIs) are one of the most important variables in resistance training; however, no known research has investigated the effects of RIs greater than 5 minutes during high-intensity strength training. The purpose of this research was to examine the effects of 3 different RIs on repetition sustainability and training volume (sets × reps × resistance) during a high-intensity bench press exercise. Fifteen resistance-trained male subjects (mean ± SD , age = 25.5 ± 4.5 years, and bench press 1 repetition maximum [1RM] ratio [1RM/body mass] = 1.39 ± 0.1) completed 3 experimental sessions, during which 4 sets of the bench press were performed with 85% of 1RM load. Subjects performed the bench press using 3 different RIs in a random counterbalanced design. Data were analyzed using both a one- and two-way analysis of variance with repeated measures. As sets progressed, repetitions were significantly different (p < 0.05) between all RIs, and only the 8-minute RI (p < 0.05) allowed for the complete sustainability of repetitions over 4 consecutive sets. Subjects attained the greatest training volume (p < 0.05) using an 8-minute RI between sets compared with a 2- or 5-minute RI. Similarly, a significantly greater training volume was achieved using the 5-minute RI compared with the 2-minute RI. Resistance-trained men, with the goal of greater volume during strength training, would benefit from longer RIs, specifically using an 8-minute RI between 4 consecutive sets of a bench press exercise. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the incidence and presentation of osteoporotic sequential bilateral hip fractures (SBHF) in Center for Joint Disease, Chonnam National University Hwasun Hospital as there are limited studies with variable results reported in Korea. Materials and Methods: Records of 507 patients aged >60 years old presenting with osteoporotic hip fractures between 2009 and 2015 were retrospectively reviewed to document the occurrence and presentation of sequential hip fractures; mean post-treatment follow-up was 48 months. Additionally, any correlations between sequential fractures and initial fracture and risk factors were assessed. Bone mineral density (BMD) was measured before and after sequential hip fracture for comparison. Results: There were 246 femoral neck (Group A) and 261 intertrochanteric (Group B) fractures. The cumulative incidence of SBHF was 8.2% (42 patients total; 29 in Group A and 13 in Group B). Average interval of SBHF for Group A and Group B were 37.4 months and 29.9 months, respectively. There was significant correlation between the initial fracture type and sequential fractures, particularly the trochanteric and subgroup of those with neck fractures. Hypertension as a co-morbidity and female sex have been identified as risk factors for SBHF. No significant findings were noted regarding BMD and risk factors in both groups. Conclusion: The clinical presentations of SBHF noted here concur with other worldwide studies and may guide efforts to develop relevant programs to prevent SBHF. [ABSTRACT FROM AUTHOR]

In this paper, a fully integrated digitally assisted low-dropout regulator (LDO) for a NAND flash memory system is proposed and verified using 500 nm I/O CMOS transistors. By combining an amplifier (AMP)-based LDO with a comparator (CMP)-based LDO, the proposed LDO achieves both fast load response in the transient state and accurate regulation in the steady state, which are advantages of the CMP-based LDO and AMP-based LDO, respectively. Moreover, loop frequency stability is satisfied in a wide range of load currents between 0 and 150 mA by using the simple structure of the gm-boost cell to insert an auxiliary path. For an input voltage range of 2.3–3 V and an output voltage of 2.1 V, the measured output droop is 225 mV for a 150 mA load step in the load transition time of 20 ns with the total bias current of 81\,\mu \rmA. The fabricated prototype chip occupies 160\,\times \,610\,\mu \rmm^2 with an on-chip output capacitor of 2 nF. [ABSTRACT FROM AUTHOR]

The dual microcatheter technique is an alternative treatment for stent-assisted coiling in acutely ruptured wide-necked aneurysms because of no antiplatelet therapy. We assessed the safety and efficacy of this technique in ruptured wide-necked aneurysms. Between March 2008 and March 2016, 56 acutely ruptured aneurysms were treated with the dual microcatheter technique. The angiographic results, treatment-related complications, and clinical outcome were documented. Angiographic follow-up was available in 37 patients at a mean of 20.6 months (6 to 81 months). On the postembolization angiograms, 27 (48.2%) aneurysms showed complete occlusion (Raymond 1), 15 (26.8%) showed neck remnant (Raymond 2), and 14 (25.0%) showed body remnant (Raymond 3). Treatment-related complications occurred in seven patients (12.5%) and six patients remained asymptomatic. The permanent complication rate was 1.8% (1/56). A good outcome (modified Rankin Scale (mRS) score, 0-2) was observed in 64.3% of patients at the time of discharge. Five patients had died, all of the sequelae of subarachnoid hemorrhage. The overall mortality rate was 8.9% (5/56); however, the treatment-related mortality rate was 0%. Of the 37 aneurysms for which angiographic follow-up was available, 21 (56.8%) aneurysms demonstrated recanalization. Five aneurysms with recanalization were retreated endovascularly. There was one aneurysm re-rupture on follow-up and it rebled 21 months after the initial procedure. The dual microcatheter technique is a safe and effective treatment for acutely ruptured wide-necked aneurysms due to low treatment-related complication and mortality rate. However, the high rate of postembolization incomplete occlusion and recanalization remains as the main challenge. [ABSTRACT FROM AUTHOR]

The need for reducing carbon emissions and achieving "Net Zero" energy has made improving heat pumps' (HPs) operational efficiency a crucial goal. However, current rule or model-based control strategies have limitations of inability to consider the entire heat production-storage-utilization cycle and inherent difficulties in achieving both high performance and generality. Here, we propose a model-free deep reinforcement learning (DRL)-based HP operation strategy that utilizes the Rainbow deep Q network algorithm to minimize electricity costs by considering thermal load demand, renewable generation, coefficient of performance (COP) of HPs, and state of charge (SOC) of thermal storage. We employ artificial neural networks to train for the regression of future load demands and COP, creating a data-driven and connectable environment with DRL. The Rainbow agent learns a creative strategy of limiting the maximum number of HP operations by increasing the SOC in advance to match future load demands. The performance of the Rainbow agent is evaluated against rule-based control in cases of future states, future uncertainty, and five-year long-term deployment. The proposed method reduces the year-round demand charge by 23.1% and the energy charge by 21.7%, resulting in a 22.2% reduction in the electricity cost. • A DRL-based heat pump operation strategy is proposed to minimize electricity cost. • A Rainbow DQN is introduced to train the control of heat pumps with future states. • DRL connectable-ANNs are employed for regression of future load demands and COP. • The Rainbow agent can optimally control HPs under five-year long-term deployment. • Year-round demand and energy charges are reduced by 23.1% and 21.7%, respectively. [ABSTRACT FROM AUTHOR]

The sensitization and intergranular corrosion associated with a phase transformation of tube-to-tubesheet welds of hyper duplex stainless steel were investigated using modified double loop electrochemical potentiokinetic reactivation. The susceptibility to sensitization of the hyper duplex stainless steel tube-to-tubesheet welded with an Ar shielding gas supplemented with nitrogen gas decreased owing to a decrease of the ferrite phase fraction and precipitation of chromium nitrides, thereby increasing the intergranular corrosion resistance. The intergranular corrosion in the hyper duplex stainless steel welds was selectively initiated at the Cr-depleted regions adjacent to the chromium nitride precipitates in the ferrite phases. [ABSTRACT FROM AUTHOR]