Functional ultrasound imaging of the human spinal cord.

Utilizing the first in-human functional ultrasound imaging (fUSI) of the spinal cord, we demonstrate the integration of spinal functional responses to electrical stimulation. We record and characterize the hemodynamic responses of the spinal cord to a neuromodulatory intervention commonly used for treating pain and increasingly used for the restoration of sensorimotor and autonomic function. We found that the hemodynamic response to stimulation reflects a spatiotemporal modulation of the spinal cord circuitry not previously recognized. Our analytical capability offers a mechanism to assess blood flow changes with a new level of spatial and temporal precision in vivo and demonstrates that fUSI can decode the functional state of spinal networks in a single trial, which is of fundamental importance for developing real-time closed-loop neuromodulation systems. This work is a critical step toward developing a vital technique to study spinal cord function and effects of clinical neuromodulation.

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.

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.

New Constraint on the Local Relic Neutrino Background Overdensity with the First KATRIN Data Runs.

We report on the direct search for cosmic relic neutrinos using data acquired during the first two science campaigns of the KATRIN experiment in 2019. Beta-decay electrons from a high-purity molecular tritium gas source are analyzed by a high-resolution MAC-E filter around the end point at 18.57 keV. The analysis is sensitive to a local relic neutrino overdensity ratio of η<9.7×10^{10}/α (1.1×10^{11}/α) at a 90% (95%) confidence level with α=1 (0.5) for Majorana (Dirac) neutrinos. A fit of the integrated electron spectrum over a narrow interval around the end point accounting for relic neutrino captures in the tritium source reveals no significant overdensity. This work improves the results obtained by the previous neutrino mass experiments at Los Alamos and Troitsk. We furthermore update the projected final sensitivity of the KATRIN experiment to η<1×10^{10}/α at 90% confidence level, by relying on updated operational conditions.

Three-dimensional soft tissue changes after reduction malarplasty in female patients.

The aim of this study was to determine the three-dimensional soft tissue changes after reduction malarplasty. Soft tissue changes relative to the amount of movement of the zygomatic bone were studied. Pre- and postoperative cone beam computed tomography images of 21 female patients were superimposed. The anterior-most point of the body osteotomy (point A), arch osteotomy site (point D), and points dividing line A-D into thirds (points B and C) were marked on lateral view images. The vertical distances from the midsagittal line to the centre of the zygomatic bone and the outer prominence of the soft tissue were measured on the coronal view of each image. The proportion of the change in soft tissue to that of the bone before and after surgery was calculated for each point. The relationship between body mass index and the soft tissue change ratio, and the differences in soft tissue changes at each point were analysed. Mean soft tissue changes for points A, B, C, and D were 53.43%, 66.66%, 63.67%, and 57.23%, respectively. The amount of soft tissue change at point B was greater than that at points A and D, which were osteotomy sites. There was no statistical correlation between body mass index and the soft tissue change ratio at each point.

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.

Wafer as an adjunct to plating patient-specific implants for the multi-segment maxilla: a useful tool.

Virtual surgical planning for orthognathic surgery using patient-specific implants (PSI) is usually waferless nowadays. However, without an occlusal wafer, difficulties arise in controlling the accuracy of multi-segment maxillary osteotomies, especially for expansion and rotational movements of each segment. It is technically challenging intraoperatively to manipulate multiple segments to fit into the PSI, as the relatively small bone segments need to be secured into the PSI while simultaneously achieving individual segment movements in all planes and with potential bony interferences with each other. Therefore, the use of a maxillary tooth-supported surgical guide is proposed and described. When the guide is inserted before the PSI, it overcomes difficulties in handling multiple maxillary segments and facilitates achieving maximal positional precision of each individual bone segment. The guide enables multiple smaller segments to behave as one unit with the designated occlusion whilst visualizing bony interferences before PSI plating is commenced. Adding a tooth-borne surgical guide in the form of a wafer and a customized arch bar is a cost-effective method to enhance accuracy in virtually planned multi-segment maxillary surgery. Further investigations are required to validate the accuracy and advantages of using wafers and PSI in multi-segment maxillary and mandibular orthognathic surgeries.

Spatial deviations of the temporomandibular joint after oncological mandibular reconstruction.

Spatial deviations of the temporomandibular joint (TMJ) after oncological mandibular reconstruction are important to the aesthetic and functional rehabilitation. The aim of this study was to clarify whether and how three dimensionally (3D) printed patient-specific surgical plates, and the preservation of the condyle or ramus, affect spatial deviations of the TMJ. A total of 33 patients who underwent mandibular reconstruction via computer-assisted surgery were included. Regarding absolute deviations, patients in the 3D-printed plate group showed smaller TMJ deviations compared to those in the conventional plate group. There was no difference in absolute deviations of the TMJ regardless of whether the condyle or ramus was preserved. Regarding physiological deviations, the impact on the contralateral TMJ was smaller in the 3D-printed plate group. Patients with both the condyle and ramus removed had significantly higher deviations of the condyle and joint space. In summary, 3D-printed patient-specific surgical plates improved the spatial accuracy of the TMJ. Under physiological conditions, TMJ deviations on the operated side were mainly affected by the preservation of the condyle. Removal of both the condyle and ramus caused more severe spatial interference to the TMJ; this should be further confirmed.

Sympathetic predominance before tourniquet deflation is associated with a reduction in arterial blood pressure after tourniquet deflation during total knee arthroplasty.

High dependency of arterial blood pressure (ABP) on enhanced sympathetic activity, which maintains vascular tone, leads to hypotension after hemodynamic insults that blunt the sympathetic activity. Therefore, we hypothesized that sympathovagal balance before tourniquet deflation (TD) determines the extent of a reduction in ABP after TD during total knee arthroplasty (TKA). Fifty-four hypertensive female patients undergoing TKA under spinal anesthesia were analyzed. The sympathovagal balance [low-to-high frequency ratio of heart rate variability (LF/HF)] before TD was defined as (LF/HF during 5 min before TD-preanesthetic LF/HF)/preanesthetic LF/HF (%). An increase in its value represents a shift in sympathovagal balance toward sympathetic predominance. The percent change in the mean ABP (MAP) after TD was defined as (minimum MAP during 10 min after TD-averaged MAP during 5 min before TD)/averaged MAP during 5 min before TD (%). Simple linear regression was performed to assess the correlation between the sympathovagal balance before TD and change in MAP after TD. The correlation was also assessed by multiple linear regression controlling for age, duration of tourniquet inflation, and spinal anesthesia-induced hypotension. Thirty-two minutes (on average) after tourniquet inflation, the MAP was decreased by 12.1 (-3.0 to 47.9) % [mean (range)] upon TD (P<0.001). The sympathovagal balance before TD was negatively proportional to the change in MAP after TD in both simple and multiple linear regression models (R2=0.323 and 0.340, P<0.001). A shift in sympathovagal balance toward sympathetic predominance before TD is associated with a decrease in ABP after TD.

Bound on 3+1 Active-Sterile Neutrino Mixing from the First Four-Week Science Run of KATRIN.

We report on the light sterile neutrino search from the first four-week science run of the KATRIN experiment in 2019. Beta-decay electrons from a high-purity gaseous molecular tritium source are analyzed by a high-resolution MAC-E filter down to 40 eV below the endpoint at 18.57 keV. We consider the framework with three active neutrinos and one sterile neutrino. The analysis is sensitive to the mass, m_{4}, of the fourth mass state for m_{4}^{2}≲1000 eV^{2} and to active-to-sterile neutrino mixing down to |U_{e4}|^{2}≳2×10^{-2}. No significant spectral distortion is observed and exclusion bounds on the sterile mass and mixing are reported. These new limits supersede the Mainz results for m_{4}^{2}≲1000 eV^{2} and improve the Troitsk bound for m_{4}^{2}<30 eV^{2}. The reactor and gallium anomalies are constrained for 100<Δm_{41}^{2}<1000 eV^{2}.

Surgical morbidities of sagittal split ramus osteotomy versus intraoral vertical ramus osteotomy for the correction of mandibular prognathism: a randomized clinical trial.

The sagittal split ramus osteotomy (SSRO) and intraoral vertical ramus osteotomy (IVRO) are two common orthognathic procedures for the treatment of mandibular prognathism. This randomized clinical trial compared the surgical morbidities between SSRO and IVRO for patients with mandibular prognathism over the first 2 years postoperative. Ninety-eight patients (40 male, 58 female) with a mean age of 24.4±3.5 years underwent bilateral SSRO (98 sides) or IVRO (98 sides) as part or all of their orthognathic surgery. IVRO presented less short-term and long-term surgical morbidity in general. The SSRO group had a greater incidence of inferior alveolar nerve deficit at all follow-up time points (P< 0.01). There was more TMJ pain at 6 weeks (P= 0.047) and 3 months (P= 0.001) postoperative in the SSRO group. The SSRO group also presented more minor complications, which were related to titanium plate exposure and infection. There were no major complications for either technique in this study. Despite the need for intermaxillary fixation, IVRO appears to be associated with less surgical morbidity than SSRO when performed as a mandibular setback procedure to treat mandibular prognathism.

3D wide-field multispectral photoacoustic imaging of human melanomas in vivo: a pilot study.

BACKGROUND: The Breslow depth is an important parameter to determine the excision margin and prognosis of melanoma. However, it is difficult to accurately determine the actual Breslow depth before surgery using the existing ocular micrometer and biopsy technique. OBJECTIVES: To evaluate the use of 3D wide-field multispectral photoacoustic imaging to non-invasively measure depth and outline the boundary of melanomas for optimal surgical margin selection. METHODS: Six melanoma patients were examined in vivo using the 3D multispectral photoacoustic imaging system. For five cases of melanomas (one in situ, three nodular, and one acral lentiginous type melanoma), the spectrally unmixed photoacoustic depths were calculated and compared against histopathological depths. RESULTS: Spectrally unmixed photoacoustic depths and histopathological depths match well within a mean absolute error of 0.36 mm. In particular, the measured minimum and maximum depths in the in situ and nodular type of melanoma were 0.6 and 9.1 mm, respectively. In the 3D photoacoustic image of one metastatic melanoma, feeding vessels were visualized in the melanoma, suggesting the neovascularization around the tumour. CONCLUSIONS: The 3D multispectral photoacoustic imaging not only provides well-measured depth and sizes of various types of melanomas, it also visualizes the metastatic type of melanoma. Obtaining accurate depth and boundary information of melanoma before surgery would play a useful role in the complete excision of melanoma during surgery.

Benign postoperative hepaticojejunostomy stricture: percutaneous recanalisation using the reverse end of a microwire.

AIM: To evaluate the technical feasibility and safety of percutaneous recanalisation of benign postoperative hepaticojejunostomy strictures using the reverse end of a microwire. MATERIALS AND METHODS: Twenty-one patients with benign postoperative hepaticojejunostomy strictures that had failed to recanalise following management with conventional percutaneous techniques from January 2012 to March 2019 were included in the study. The stricture was punctured by the reverse end of a microwire. Subsequently, serial balloon dilatation and covered stent placement was performed. Technical as well as clinical success, complications, and patency of the hepaticojejunostomy were evaluated. RESULTS: Technical success was achieved in 19 of 21 (90.5%) patients. The mean number of treatment sessions was 1.2 (range, 1-2). The obstructive symptoms were resolved within 3 days after the procedure in 19 patients (100%). There were no major complications. The 1-year and 3-year patency rates were 76.9% and 61.5%, respectively. CONCLUSION: Percutaneous recanalisation using the reverse end of a microwire is technically feasible and safe in the treatment of benign postoperative hepaticojejunostomy strictures. This technique is useful when the conventional percutaneous technique cannot be used to cross the stricture.

Epigenetic profiling demarcates molecular subtypes of muscle-invasive bladder cancer.

Muscle-invasive bladder cancer (MIBC) is a heterogeneous disease that often recurs despite aggressive treatment with neoadjuvant chemotherapy and (radical) cystectomy. Basal and luminal molecular subtypes have been identified that are linked to clinical characteristics and have differential sensitivities to chemotherapy. While it has been suggested that epigenetic mechanisms play a role in defining these subtypes, a thorough understanding of the biological mechanisms is lacking. This report details the first genome-wide analysis of histone methylation patterns of human primary bladder tumours by chromatin immunoprecipitations and next-generation sequencing (ChIP-seq). We profiled multiple histone marks: H3K27me3, a marker for repressed genes, and H3K4me1 and H3K4me3, which are indicators of active enhancers and active promoters. Integrated analysis of ChIP-seq data and RNA sequencing revealed that H3K4 mono-methylation demarcates MIBC subtypes, while no association was found for the other two histone modifications in relation to basal and luminal subtypes. Additionally, we identified differentially methylated H3K4me1 peaks in basal and luminal tumour samples, suggesting that active enhancers play a role in defining subtypes. Our study is the first analysis of histone modifications in primary bladder cancer tissue and provides an important resource for the bladder cancer community.

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.

Timing of antibiotics in septic patients: a prospective cohort study.

OBJECTIVES: To evaluate the effect of timing and appropriateness of antibiotics administration on mortality in patients diagnosed with sepsis according to the Sepsis-3 definition. METHODS: This prospective cohort study was conducted in patients diagnosed with sepsis according to the Sepsis-3 definition at the emergency department of Korea University Ansan Hospital from January 2016 to January 2019. The time to antibiotics was defined as the time in hours from emergency department arrival to the first antibiotic administration. Cox proportional hazards regression analysis was used to estimate the association between time to antibiotics and 7-, 14- and 28-day mortality. RESULTS: Of 482 patients enrolled onto this study, 203 (42.1%) of 482 and 312 (64.7%) of 482 were diagnosed with septic shock and high-grade infection respectively. The median time to receipt of antibiotic therapy was 115 minutes. Antibiotics were administered within 3 and 6 hours in 340 (70.4%) of 482 and 450 (93.2%) of 482 patients respectively. Initial appropriate empirical antibiotics were administered in 375 (77.8%) of 482 patients. The time to and appropriateness of the initial antibiotics were not associated with 7-, 14- and 28-day mortality in multivariate analysis. The Sequential Organ Failure Assessment (SOFA) score (adjusted hazard ratio (aHR) 1.229, 95% confidence interval (CI) 1.093-1.381, p 0.001) and initial lactate levels (aHR 1.128, 95% CI 1.034-1.230, p 0.007), Charlson comorbidity index (aHR 1.115, 95% CI 1.027-1.210, p 0.014), 2-hour lactate level (aHR 1.115, 95% CI 1.027-1.210, p 0.009) and SOFA score (aHR 1.077, 95% CI 1.013-1.144, p 0.018) affected 7-, 14- and 28-day mortality respectively. Subgroup analysis with septic shock, bacteraemia and high-grade infection did not affect mortality rates. CONCLUSIONS: Time to receipt of antibiotics may not affect the prognosis of patients with sepsis if a rapid and well-trained resuscitation is combined with appropriate antibiotic administration within a reasonable time.

Prospective randomized comparison of cerebrospinal fluid aspiration and conventional popping methods using 27-gauge spinal needles in patients undergoing spinal anaesthesia.

BACKGROUND: Performing spinal anaesthesia using the conventional popping method with a 27-gauge (27G) spinal needle is technically difficult. In this study, we compared the aspiration and conventional popping method for spinal anaesthesia using 27G Quincke-type needles. METHODS: This prospective, randomized study enrolled 90 patients, aged 19 to 65 years, with American Society of Anesthesiologists physical status I-III, who were undergoing spinal anaesthesia. Patients were randomly assigned to one of two groups using a computer-generated random number table: patients receiving spinal anaesthesia using the aspiration method, in which the needle is advanced with continuous aspiration, or the conventional popping method. The primary outcome measure was the success rate of the first attempt to perform dural puncture. Number of attempts and passages, withdrawal cases, successful attempt time, total procedure time, and actual depth of dural puncture were recorded. RESULTS: Eighty-eight patients were included in the study. In the aspiration group, the success rate of first attempt for dural puncture was 93.3%, compared with 72.1% in the popping group (P = 0.019). Success involving needle withdrawal was recorded in 4 (8.9%) patients in the aspiration group and 13 (30.2%) in the popping group (P = 0.024). In the popping group, the number of attempts was significantly higher (P = 0.044), and total procedure time was significantly longer (P = 0.023). Actual depths of dural puncture were deeper in the popping group than in the aspiration group (P = 0.019). CONCLUSIONS: The aspiration method using a 27G Quincke-type needle offers clinical benefits for dural puncture compared with the conventional popping method for spinal anaesthesia. TRIAL REGISTRATION: Clinical research information service number: KCT0002815, registered 21/Apr/2018. Retrospectively registered.

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.