Effect of fall characteristics on the severity of hip impact during a fall on the ground from standing height.

The magnitude of hip impact force during a fall on the ground (i.e., concrete surface) from standing height was determined. We found that this force decreases up to 59%, depending on how they land on the ground. INTRODUCTION: We determined the magnitude of hip impact force that humans may experience in the event of a fall from standing height on the ground, in order to examine how the hip impact force was affected by characteristics of a fall. METHODS: Twenty subjects mimicked a typical older adults' falls on a mat. Trials were acquired with three initial fall directions: forward, sideways, and backward. Trials were also acquired with three knee positions at the time of hip impact: knee together, knee on the mat, and free knee. During falls, attenuated vertical hip impact forces and corresponding depression of the mat were measured via a force plate placed under the mat and motion capture system, respectively. Using a mass-spring model, actual hip impact force and body stiffness during a fall on the ground were estimated. RESULTS: Hip impact force averaged 4.0 kN (SD = 1.7). The hip impact force was associated with knee condition (F = 25.6, p < 0.005), but not with fall direction (F = 0.4, p = 0.599). Compared with "knee on the mat," hip impact force averaged 59% and 45% greater in "free knee" and "knee together," respectively (4.6 versus 2.9 kN, p < 0.005; 4.3 versus 2.9 kN, p < 0.005). However, the hip impact force did not differ between "free knee" and "knee together (4.6 versus 4.3 kN, p = 0.554). CONCLUSION: Our results suggest that hip fracture risk during a fall decreases substantially, depending on how they land on the ground, informing the development of safe landing strategies to prevent fall-related hip fractures in older adults.

Desflurane reduces intraoperative remifentanil requirements more than sevoflurane: comparison using surgical pleth index-guided analgesia.

BACKGROUND: Sevoflurane and desflurane are widely used in balanced anaesthesia in combination with opioid analgesics. The opioid remifentanil is frequently chosen because of its extremely rapid pharmacokinetics. However, intraoperative high-dose remifentanil is associated with increased postoperative pain and rescue analgesic use owing to acute tolerance and opioid-induced hyperalgesia. This study aimed to compare intraoperative remifentanil requirements during equi-minimum alveolar concentration (MAC) sevoflurane and desflurane anaesthesia via surgical pleth index-guided remifentanil administration. METHODS: Eighty-two subjects undergoing laparoscopic cholecystectomy were randomly allocated to two groups receiving either sevoflurane (n=40) or desflurane (n=42). Anaesthesia was maintained with the assigned inhaled anaesthetics and remifentanil. End-tidal anaesthetic concentration was maintained at age-corrected 1.0 MAC, and remifentanil infusion was continuously adjusted to achieve a surgical pleth index of 20-50. Mean remifentanil infusion rate, which was the primary outcome of the study, was calculated as the total infused remifentanil dose per kg body weight per minute of total operative time. RESULTS: Mean remifentanil infusion rate [mean (standard deviation)] was significantly higher in the sevoflurane group than in the desflurane group [0.192 (0.064) vs. 0.099 (0.033) µg kg-1 min-1; difference, 0.093 (95% confidence interval, 0.071-0.115); P<0.001]. CONCLUSIONS: During equi-MAC anaesthesia of 1.0 MAC, sevoflurane and desflurane did not show similar intraoperative remifentanil consumption under surgical pleth index-guided opioid administration. Further studies using other monitors with different measuring mechanisms are warranted to determine the cause of this difference. CLINICAL TRIAL REGISTRATION: NCT02830243 (ClinicalTrials.gov).

Inhibition of microRNA-449a prevents IL-1ß-induced cartilage destruction via SIRT1.

OBJECTIVE: SIRT1 has anti-inflammatory as well as protective effects in chondrocytes. The object of this study was to investigate whether microRNA-449a regulates expression of SIRT1, which inhibits expression of catabolic genes in IL-1ß-induced cartilage destruction. MATERIALS AND METHODS: MicroRNA-449a expression was determined in OA chondrocytes and IL-1ß-induced chondrocytes by real-time PCR. MicroRNA-449a binding sites on the 3'-UTR of SIRT1 mRNA and binding site conservation were examined using microRNA target prediction tools. SIRT1-overexpressing or knockdown chondrocytes were transfected with microRNA-449a or anti-microRNA-449a mimic and stimulated by IL-1ß. Expression of catabolic and anabolic genes was examined by real-time PCR and western blotting. Finally, positive effects of anti-microRNA-449a on expression of these genes were confirmed by western analysis of OA chondrocytes. RESULTS: Expression of microRNA-449a was increased in OA chondrocytes and IL-1ß-induced chondrocytes. MMP-13 expression was enhanced, whereas type II collagen and SIRT1 expression were decreased in IL-1ß-induced chondrocytes. SIRT1 overexpression resulted in decreased expression of catabolic genes such as MMPs and ADAMTSs in response to IL-1ß, but these effects were moderated by microRNA-449a. Suppression of microRNA-449a by anti-microRNA-449a inhibited expression of catabolic genes despite IL-1ß stimulation, but these effects were abolished in SIRT1 knockdown chondrocytes. Furthermore, expression of catabolic genes was decreased and expression of type II collagen as well as SIRT1 was restored by anti-microRNA-449a in OA chondrocytes as well as in IL-1ß-induced chondrocytes. CONCLUSION: Silencing of microRNA-449a had a protective effect, inhibiting catabolic gene expression and restoring anabolic gene expression, by targeting SIRT1 in IL-1ß-induced cartilage destruction.

A randomised controlled trial comparing continuous supraclavicular and interscalene brachial plexus blockade for open rotator cuff surgery.

Continuous interscalene block is an approved modality for postoperative pain control, but it may cause hemidiaphragmatic paresis. In this study we aimed to determine whether continuous supraclavicular block would provide postoperative analgesia comparable to that of continuous interscalene block and reduce the incidence of hemidiaphragmatic paresis. Patients scheduled for open rotator cuff repair were randomly allocated to receive continuous interscalene (n = 38) or supraclavicular block (n = 37). Both participants and assessing clinicians were blinded to the group allocation. The primary endpoint was the mean pain intensity 24 h after the surgery. Postoperative mean (SD) pain scores at 24 h were similar in the supraclavicular and interscalene groups (2.57 (1.71) vs 2.84 (1.75) respectively; p = 0.478). The incidence of complete or partial hemidiaphragmatic paresis was lower in the supraclavicular group at 1 h after admission to the postanaesthetic care unit and 24 h after the surgery [25 (68%) vs 38 (100%); p = 0.001 and 14 (38%) vs 27 (71%) respectively; p = 0.008]. Continuous supraclavicular block provided comparable analgesia compared with interscalene block with a reduced incidence of complete or partial hemidiaphragmatic paresis for 24 h following surgery.

Spinal Accessory Nerve: Ultrasound Findings and Correlations with Neck Lymph Node Levels.

Purpose: To evaluate the ultrasound characteristics of the spinal accessory nerve (SAN) and correlate nerve location with neck lymph node level. Materials and Methods: 50 participants with 100 SANs were enrolled in this study. The SAN was traced from the trapezius muscle to the upper neck and was identified by a hypoechoic linear structure without color Doppler flow. The ultrasound characteristics of the SAN, such as visibility, diameter, relationship with adjacent structures, and its correlation with lymph node levels, were evaluated. Results: The SAN was identified in 96 %-100 % of segments. The mean diameter of the SAN was 0.54 ±â€Š0.09 mm. The SANs was located between the trapezius and levator scapulae muscles and 90.8 % were traced into the trapezius muscle. In the upper neck, the SAN passed deep into the sternocleidomastoid (SCM) muscle in 38 % of cases and between the two heads of the SCM muscle in 62 % of cases. The SAN was found at neck lymph node levels II, III, IV, and V, but not I or VI. Conclusion: Continuous ultrasound monitoring of the SAN and its correlation with lymph node levels is possible in most patients. Our current findings may assist in the future prevention of SAN injury during ultrasound-guided procedures.

Effects of hip abductor muscle forces and knee boundary conditions on femoral neck stresses during simulated falls.

UNLABELLED: Through experiments that simulated sideways falls with a mechanical hip impact simulator, we demonstrated the protective effect of hip abductor muscle forces in reducing peak stresses at the femoral neck and the corresponding risk for hip fracture. INTRODUCTION: Over 90% of hip fractures are due to falls, and an improved understanding the factors that separate injurious and non-injurious falls (via their influence on the peak stress generated at the femoral neck) may lead to improved risk assessment and prevention strategies. The purpose of this study was to measure the effect of muscle forces spanning the hip, and knee boundary conditions, on peak forces and estimated stresses at the femoral neck during simulated falls with a mechanical system. METHODS: We simulated hip abductor muscle forces and knee boundary conditions with a mechanical hip impact simulator and measured forces and stresses at the femoral neck during sideways falls. RESULTS: Peak compressive and tensile stresses, shear force, bending moment, and axial force are each associated with hip abductor muscle forces and knee boundary conditions (p < 0.0005). When muscle force increased from 400 to 1,200 N, peak compressive and tensile stresses decreased 24 and 56%, respectively. These effects were similar to the magnitude of decline in fracture strength associated with osteoporosis and arose from the tension-band effect of the muscle in reducing the bending moment by 37%. Furthermore, peak compressive and tensile stresses averaged 40 and 51% lower, respectively, in the free knee than fixed knee condition. CONCLUSIONS: Contraction of the hip abductor muscles at the moment of impact during a fall, and landing with the knee free of constraints, substantially reduced peak compressive and tensile stresses at the femoral neck and risk for femoral fracture in a sideways fall.

Potential nonmonotonous association between di(2-ethylhexyl) phthalate exposure and atopic dermatitis in Korean children.

BACKGROUND: Concerns have emerged about the adverse effect of phthalates on human health. OBJECTIVES: The aim of this study was to investigate the association between di(2-ethylhexyl) phthalate (DEHP) exposure and atopic dermatitis (AD) in Korean children, focusing on the potential dose-response relationship. METHODS: A matched case-control study was conducted from May to October 2012. Subjects from 3 to 6 years of age were recruited from kindergartens and daycare centres in Seoul, Korea. The clinical diagnosis of AD was made by dermatologists. A total of 224 cases and 224 age- and sex-matched controls were included. The levels of two phthalate metabolites [mono(2-ethyl-5-hydrohexyl) phthalate (MEHHP) and mono(2-ethyl-5-oxohexyl) phthalate (MEOHP)] of DEHP in urine samples were measured. RESULTS: The effects of DEHP varied by age, and an increased risk for AD was associated with DEHP at age 3 years (odds radio 2.51, 95% confidence interval 1.02-6.20). The association was in the opposite direction in the other age groups although there was no statistical significance. The effects of DEHP on AD was observed differently by the level of the body burden. The predicted risk for AD based on the results of multiple logistic regression analysis showed a nonmonotonous association (U-shaped) between the level of DEHP and the risk of AD. CONCLUSIONS: This finding might suggest that the effects of DEHP on AD may be different according to the exposure level or age of the subject. Further longitudinal investigations with a suitable design to investigate the nonmonotonous association should be encouraged.

Vertical growth of core-shell III-V nanowires for solar cells application.

High density (In)GaAs/GaAs/AIGaAs nanowires (NWs) consisting of n-type core and p-type shell have been vertically grown on (111) GaAs substrate using metal organic chemical vapor deposition (MOCVD) and fabricated into solar cells. Au colloidal nanoparticles (NPs) are employed as a catalyst. High density nanowires were obtained by uniform distribution of Au NPs. Fe-SEM, TEM and HRTEM images show that the morphology of shell is sensitive to p-doping concentration. Increase in the density of p-doping precursor results in "kinking" of NPs and rough shell surface. The origin of kinking has been explained by the GaAs twin phases due to Zn segregation on the surface of shell. It has been observed that the morphology of NPs can be controlled through optimizing various source purge technique of DEZn and deposition temperature. Electrical properties of core-shell doped NWs are carried out using I-V characterization. The core-shell NWs show characteristics of p-n junction as revealed by I-V studies.

Effect of growth temperature and quantum structure on InAs/GaAs quantum dot solar cell.

InGaAs-capped InAs quantum dots (QDs) and InAs QDs were adopted for the study of the effects through growth temperature and the band structure of InAs QDs on the performance of GaAs-based QD solar cell. It has been shown that the defects due to low temperature growth resulted in the decrease of Voc, Jsc and external quantum efficiency for GaAs bulk solar cell and QD embedded solar cells. It has been also found that InAs QDs act as defects by trapping photo-generated carries which affect the carrier transport in QD solar cell. The QD solar cell with InGaAs-capped InAs QDs showed higher performance than the QD solar cell with only InAs QDs. Such result has been explained by photo-generated carrier trapping and tunneling through InGaAs QW state in InGaAs-capped InAs QDs.

Fabrication of GaAs/Al0.3Ga0.7As multiple quantum well nanostructures on (100) si substrate using a 1-nm InAs relief layer.

Nanometer scale thin InAs layer has been incorporated between Si (100) substrate and GaAs/Al0.3Ga0.7As multiple quantum well (MQW) nanostructure in order to reduce the defects generation during the growth of GaAs buffer layer on Si substrate. Observations based on atomic force microscopy (AFM) and transmission electron microscopy (TEM) suggest that initiation and propagation of defect at the Si/GaAs interface could be suppressed by incorporating thin (1 nm in thickness) InAs layer. Consequently, the microstructure and resulting optical properties improved as compared to the MQW structure formed directly on Si substrate without the InAs layer. It was also observed that there exists some limit to the desirable thickness of the InAs layer since the MQW structure having thicker InAs layer (4 nm-thick) showed deteriorated properties.

Effects of hip joint kinematics on the effective pelvis stiffness and hip impact force during simulated sideways falls.

Improved understanding is required on how hip fracture risk is influenced by landing configuration. We examined how hip impact dynamics was affected by hip joint kinematics during simulated sideways falls. Twelve young adults (7 males, 5 females) of mean age 23.5 (SD = 1.5) years, participated in pelvis release experiments. Trials were acquired with the hip flexed 15° and 30° for each of three hip rotations: +15° ("external rotation"), 0°, and -15° ("internal rotation"). During falls, force-deformation data of the pelvis were recorded. Outcome variables included the peak hip impact force (Fexperimental) and effective stiffness of the pelvis (k1st, ksecant, and kms) determined with different methods suggested in literature, and predicted hip impact force during a fall from standing height (F1st, Fsecant and Fms). The two-way repeated-measures ANOVA was used to test whether these variables were associated with hip joint angles. The Fexperimental, ksecant and Fsecant were associated with hip rotation (F = 5.587, p = 0.005; F = 9.278, p < 0.0005; F = 5.778, p = 0.004, respectively), and 15 %, 31 % and 17 % smaller in 15° external than internal rotation (848 versus 998 N; 24.6 versus 35.6 kN/m; 2,637 versus 3,170 N, respectively). However, none of the outcome variables were associated with hip flexion (p > 0.05). Furthermore, there were no interactions between the hip rotation and flexion for all outcome variables (p > 0.05). Our results provide insights on hip impact dynamics, which may help improve a hip model to assess hip fracture risk during a fall.

Risk of Dementia in Korean Vietnam War Veterans.

BACKGROUND: The number of cases of all types of dementia is increasing, and a significant increase in prevalence has been noted among veterans. Evidence of an association between dementia and exposure to chemicals such as Agent Orange from the Vietnam War is still limited, and there is a reported lack of awareness. OBJECTIVE: This study aimed to investigate the risk of dementia among Vietnam War veterans in Korea. DESIGN: This retrospective longitudinal study compared the incidence of dementia between Vietnam War veterans and the general population. SETTING: This study used data from the nationally representative Korean Vietnam War Veterans' Health Study Cohort, a combined dataset sourced from the Ministry of Patriots and Veterans Affairs in Korea and the National Health Insurance Sharing Service database. PARTICIPANTS: There were 191,272 Vietnam War veterans and 1,000,320 people of different ages, sexes, and residences. matched control in 2002. The total number of person-years were 18,543,181. MEASUREMENTS: The dementia group included participants who had visited a medical facility with any of the following ICD-10 codes in the follow-up periods: "F00 Dementia in Alzheimer's disease," "F01 Vascular dementia," "F02 Dementia in other diseases classified elsewhere," or "F03 Unspecified dementia." RESULTS: The incidence rate ratio for all types of dementia was 1.16, with higher ratios observed for vascular and unspecified dementia, particularly in the younger age groups. There was a significant increase in the risk of dementia, Alzheimer's disease, vascular dementia, and unspecified dementia. CONCLUSION: Vietnam War veterans showed an increased risk for all types of dementia. These findings are hypothesized to be due to the effects of the chemicals used during the Vietnam War, which can cause a variety of neurodegenerative diseases. Further studies are warranted to investigate the potential health determinants related to the Vietnam War, focusing on the neurodegenerative effects.

Association between Sarcopenia and Survival in Patients Undergoing Gamma Knife Surgery for Brain Metastasis from Breast Cancer: A Retrospective Single-centre Cohort Study.

AIMS: Many recent studies related to cancer surgery have reported that sarcopenia influences mortality in surgical patients. However, few comprehensive studies have examined the associations between sarcopenia and short- and long-term surgical outcomes of metastatic cancer, especially breast cancer with brain metastasis. In the present study, we investigated the association between sarcopenia and mortality in patients who underwent gamma knife radiosurgery (GKRS) for brain metastasis with breast cancer. MATERIALS AND METHODS: This retrospective study analysed 157 patients who underwent GKRS for brain metastasis with breast cancer between January 2014 and December 2018. A Cox regression analysis was carried out to evaluate the association between sarcopenia and mortality at 90 days, 180 days, 1 year, 3 years and the overall period. RESULTS: In the Cox regression analysis, sarcopenia was significantly associated with high 90-day mortality (adjusted hazard ratio 3.46, 95% confidence interval 1.24-9.67, P = 0.018), 180-day mortality (adjusted hazard ratio 2.67, 95% confidence interval 1.37-5.22, P = 0.004), 1-year mortality (adjusted hazard ratio 2.39, 95% confidence interval 1.42-4.02, P = 0.001), 3-year mortality (adjusted hazard ratio 2.39, 95% confidence interval 1.53-3.74, P < 0.001) and overall mortality (adjusted hazard ratio 2.11, 95% confidence interval 1.37-3.26, P < 0.001). CONCLUSION: Sarcopenia could be a risk factor for short- and long-term mortality in patients undergoing GKRS for brain metastasis from breast cancer.

Punctuated growth of InAs quantum dashes-in-a-well for enhanced 2-µm emission.

InAs quantum dashes (Qdash) engineered to emit near 2 µm are envisioned to be promising quantum emitters for next-generation technologies in sensing and communications. In this study, we explore the effect of punctuated growth (PG) on the structure and optical properties of InP-based InAs Qdashes emitting near the 2-µm wavelength. Morphological analysis revealed that PG led to an improvement in in-plane size uniformity and increases in average height and height distribution. A 2 × boost in photoluminescence intensity was observed, which we attribute to improved lateral dimensions and structural stabilization. PG encouraged formation of taller Qdashes while photoluminescence measurements revealed a blue-shift in the peak wavelength. We proposed that the blue-shift originates from the thinner quantum well cap and decreased distance between the Qdash and InAlGaAs barrier. This study on the punctuated growth of large InAs Qdashes is a step toward realizing bright, tunable, and broadband sources for 2-µm communications, spectroscopy, and sensing.

Effects of hip muscle activation on the stiffness and energy absorption of the trochanteric soft tissue during impact in sideways falls.

The trochanteric soft tissue attenuates impact force or absorbs impact energy during a fall on the hip (thereby helps to reduce a risk of hip fracture). While the benefits should be affected by contractions of muscles spanning the hip joint, no information is available to date. We examined how the stiffness (force attenuation capacity) and energy absorption of the trochanteric soft tissue were affected by hip muscle activation during a fall. Thirteen healthy young individuals (5 males, 8 females) participated in the pelvis release experiment. Falling trials were acquired with three muscle contraction conditions: 0-20% ("relaxed"), 20-50% ("moderate"), and 60-100% ("maximal") of the maximal voluntary isometric contraction of the gluteus medius muscle. During trials, we measured real-time force and deformation behaviour of the trochanteric soft tissue. Outcome variables included the stiffness and energy absorption of the soft tissue. The stiffness and energy absorption ranged from 56.1 to 446.9 kN/m, and from 0.15 to 2.26 J, respectively. The stiffness value increased with muscle contraction, and 59% greater in "maximal" than "relaxed" condition (232.2 (SD = 121.4) versus 146.1 (SD = 49.9)). However, energy absorption decreased with muscle contraction, and 58.9% greater in "relaxed" than "maximal" condition (0.89 (SD = 0.63) versus 0.56 (SD = 0.41)). Our results provide insights on biomechanics of the trochanteric soft tissue ("natural" padding device) during impact stage of a fall, suggesting that soft tissues' protective benefits are largely affected by the level of muscle contraction.

Effect of pre-exposure to sevoflurane on the bispectral index in women undergoing Caesarean delivery under general anaesthesia.

BACKGROUND: Patients undergoing Caesarean delivery under inhalation anaesthesia are at a high risk of awareness, especially in the period before delivery. We assessed the effects of pre-exposure to sevoflurane on the bispectral index (BIS) in the interval before delivery. METHODS: Sixty-four patients undergoing elective Caesarean delivery were randomly assigned to receive 1.0-1.1 vol% (control 1) or 1.2-1.3 vol% (control 2) end-tidal sevoflurane, or the same concentrations of end-tidal sevoflurane combined with pre-exposure to 1 vol% sevoflurane for the last 1 min of the preoxygenation period (the preSevo 1 and preSevo 2 groups, respectively). We assessed BIS values, arterial pressure, and heart rate at the time of induction; before intubation; and upon skin incision, uterine incision, and delivery. We also determined the maternal incidence of intraoperative awareness and the neonatal Apgar scores, and conducted umbilical blood gas analysis. RESULTS: At skin incision, BIS values were significantly lower in the preSevo 1 group than in the control 1 group [50 (13) vs 72 (8), P<0.001] and in the preSevo 2 group than in the control 2 group [44 (11) vs 67 (10), P<0.001]. The mean BIS values in the preSevo 1 and 2 groups were maintained below 60 in the period before delivery. No other parameter differed among groups, and no patient exhibited intraoperative awareness. CONCLUSIONS: Pre-exposure to low concentrations of sevoflurane reduced BIS values in the interval before delivery, suggesting that this approach may reduce the risk of maternal awareness. Clinical Research Information Service (code KCT0000069, http://cris.cdc.go.kr).

Long-term outcomes of ablation, liver resection, and liver transplant as first-line treatment for solitary HCC of 3 cm or less using an intention-to-treat analysis: A retrospective cohort study.

Background: Curative-intent therapies for hepatocellular carcinoma (HCC) include radiofrequency ablation (RFA), liver resection (LR), and liver transplantation (LT). Controversy exists in treatment selection for early-stage tumours. We sought to evaluate the oncologic outcomes of patients who received either RFA, LR, or LT as first-line treatment for solitary HCC ≤ 3 cm in an intention-to-treat analysis. Materials and methods: All patients with solitary HCC ≤ 3 cm who underwent RFA, LR, or were listed for LT between Feb-2000 and Nov-2018 were analyzed. Cox regression analysis was then performed to compare intention-to-treat (ITT) survival by initial treatment allocation and disease-free survival (DFS) by treatment received in patients eligible for all three treatments. Results: A total of 119 patients were identified (RFA n = 83; LR n = 25; LT n = 11). The overall intention-to-treat survival was similar between the three groups. The overall DFS was highest for the LT group. This was significantly higher than RFA (p = 0.02), but not statistically significantly different from LR (p = 0.14). After multivariable adjustment, ITT survival was similar in the LR and LT groups relative to RFA (LR HR:1.13, 95%CI 0.33-3.82; p = 0.80; LT HR:1.39, 95%CI 0.35-5.44; p = 0.60). On multivariable DFS analysis, only LT was better relative to RFA (LR HR:0.52, 95%CI 0.26-1.02; p = 0.06; LT HR:0.15, 95%CI 0.03-0.67; p = 0.01). Compared to LR, LT was associated with a numerically lower hazard on multivariable DFS analysis, though this did not reach statistical significance (HR 0.30, 95%CI 0.06-1.43; p = 0.13). Conclusion: For treatment-naïve patients with solitary HCC ≤ 3 cm who are eligible for RFA, LR, and LT, adjusted ITT survival is equivalent amongst the treatment modalities, however, DFS is better with LR and LT, compared with RFA. Differences in recurrence between treatment modalities and equipoise in ITT survival provides support for a future prospective trial in this setting.

Effect of the proton irradiation on the thermally activated flux flow in superconducting SmBCO coated conductors.

We investigate changes in the vortex pinning mechanism caused by proton irradiation through the measurement of the in-plane electrical resistivity for H//c in a pristine and two proton-irradiated (total doses of 1 × 1015 and 1 × 1016 cm-2) SmBa2Cu3O7-δ (SmBCO) superconducting tapes. Even though proton irradiation has no effect on the critical temperature (Tc), the resulting artificial point defect causes an increase in normal state electrical resistivity. The electrical resistivity data around Tc shows no evidence of a phase transition to the vortex glass state but only broadens with increasing magnetic field due to the vortex depinning in the vortex liquid state. The vortex depinning is well interpreted by a thermally activated flux flow model in which the activation energy shows a nonlinear temperature change [Formula: see text] (q = 2). The field dependence of activation energy shows a [Formula: see text] with larger exponents above 4 T. This field dependence is mainly due to correlated disorders in pristine sample and artificially created point defects in irradiated samples. Compared with the vortex pinning due to correlated disorders, the vortex pinning due to the appropriate amount of point defects reduces the magnitude of Uo(H) in the low magnetic field region and slowly reduces Uo(H) in high magnetic fields.

Cerebral epidural hematoma following cerebrospinal fluid drainage during thoracoabdominal aortic repair.

Cerebrospinal fluid (CSF) drainage is a common adjunct to thoracoabdominal aortic aneurysm (TAAA) repair. CSF drainage may improve perioperative spinal cord perfusion and thereby decrease the incidence of paraplegia or paraparesis. Complications of CSF drainage may arise. We present a case of cerebral epidural hematoma (EDH), possibly arising from excessive CSF drainage, during thoracoabdominal aortic repair.

Soft tissue stiffness over the hip increases with age and its implication in hip fracture risk in older adults.

Risk of hip fracture depends on the bone strength as well as the impact force delivered to the proximal femur during falls, and femoral soft tissue may help to reduce the hip fracture risk by attenuating the impact force. Femoral soft tissue stiffness was measured from a large sample, and compared how this was affected by age, gender and site. One hundred fifty healthy individuals (fifty-two young (aged between 19 and 29), forty-eight middle-aged (30-64), and fifty old (over 65)) participated. Each age group included an equal number of males and females. Using an automated hand-held indentation device, soft tissue stiffness was measured over twelve sites with respect to the greater trochanter (GT). For both left and right hips, the stiffness was associated with age (p < 0.0005), gender (p < 0.0005), and site (p < 0.0005). On average, the stiffness was 26% greater in older than young adults (321.5 versus 254.3 N/m). On average across twelve sites, the regression analysis indicated that the stiffness increases 1.33 N/m every year ("soft tissue stiffness over the hip = 1.33*age + 221.8"; R = 0.518, p < 0.0005). Furthermore, the stiffness was 18% greater in male than female (308.8 versus 262.6 N/m), and differed across twelve sites over the hip, being greatest (424.2 N/m) at the GT, and least (206.3 N/m) at the superior gluteal region. The results provide insights into the shock absorbing property of soft tissue over the hip, and inform the improvement of fall-related injury prevention interventions (i.e., hip protector, safe landing strategies) in older adults.