Resting-state functional MR imaging has been used for motor mapping in presurgical planning but never used intraoperatively. This study aimed to investigate the feasibility of applying intraoperative ...resting-state functional MR imaging for the safe resection of gliomas using real-time motor cortex mapping during an operation.
Using interventional MR imaging, we conducted preoperative and intraoperative resting-state intrinsic functional connectivity analyses of the motor cortex in 30 patients with brain tumors. Factors that may influence intraoperative imaging quality, including anesthesia type (general or awake anesthesia) and tumor cavity (filled with normal saline or not), were studied to investigate image quality. Additionally, direct cortical stimulation was used to validate the accuracy of intraoperative resting-state fMRI in mapping the motor cortex.
Preoperative and intraoperative resting-state fMRI scans were acquired for all patients. Fourteen patients who successfully completed both sufficient intraoperative resting-state fMRI and direct cortical stimulation were used for further analysis of sensitivity and specificity. Compared with those subjected to direct cortical stimulation, the sensitivity and specificity of intraoperative resting-state fMRI in localizing the motor area were 61.7% and 93.7%, respectively. The image quality of intraoperative resting-state fMRI was better when the tumor cavity was filled with normal saline (
= .049). However, no significant difference between the anesthesia types was observed (
= .102).
This study demonstrates the feasibility of using intraoperative resting-state fMRI for real-time localization of functional areas during a neurologic operation. The findings suggest that using intraoperative resting-state fMRI can avoid the risk of intraoperative seizures due to direct cortical stimulation and may provide neurosurgeons with valuable information to facilitate the safe resection of gliomas.
Aims/hypothesis
The aim of this work was to evaluate the efficacy and safety of canagliflozin vs placebo and sitagliptin in patients with type 2 diabetes who were being treated with background ...metformin.
Methods
This randomised, double-blind, four-arm, parallel-group, Phase 3 study was conducted at 169 centres in 22 countries between April 2010 and August 2012. Participants (
N
= 1,284) with type 2 diabetes aged ≥18 and ≤80 years who had inadequate glycaemic control (HbA
1c
≥7.0% 53 mmol/mol and ≤10.5% 91 mmol/mol) on metformin therapy received canagliflozin 100 mg or 300 mg, sitagliptin 100 mg, or placebo (
n
= 368, 367, 366, 183, respectively) for a 26 week, placebo- and active-controlled period followed by a 26 week, active-controlled period (placebo group switched to sitagliptin placebo/sitagliptin) and were included in the modified intent-to-treat analysis set. Randomisation was performed using a computer-generated schedule; participants, study centres and the sponsor were blinded to group assignment. The primary endpoint was change from baseline in HbA
1c
at week 26; secondary endpoints included changes in HbA
1c
(week 52) and fasting plasma glucose (FPG), body weight, and systolic blood pressure (BP; weeks 26 and 52). Adverse events (AEs) were recorded throughout the study.
Results
At week 26, canagliflozin 100 mg and 300 mg reduced HbA
1c
vs placebo (−0.79%, –0.94%, –0.17%, respectively;
p
< 0.001). At week 52, canagliflozin 100 mg and 300 mg demonstrated non-inferiority, and canagliflozin 300 mg demonstrated statistical superiority, to sitagliptin in lowering HbA
1c
(−0.73%, –0.88%,–0.73%, respectively); differences (95% CI) vs sitagliptin were 0% (−0.12, 0.12) and −0.15% (−0.27, –0.03), respectively. Canagliflozin 100 mg and 300 mg reduced body weight vs placebo (week 26: –3.7%, –4.2%, –1.2%, respectively;
p
< 0.001) and sitagliptin (week 52: –3.8%, –4.2%, –1.3%, respectively;
p
< 0.001). Both canagliflozin doses reduced FPG and systolic BP vs placebo (week 26) and sitagliptin (week 52) (
p
< 0.001). Overall AE and AE-related discontinuation rates were generally similar across groups, but higher with canagliflozin 100 mg. Genital mycotic infection and osmotic diuresis-related AE rates were higher with canagliflozin; few led to discontinuations. Hypoglycaemia incidence was higher with canagliflozin.
Conclusions/interpretation
Canagliflozin improved glycaemia and reduced body weight vs placebo (week 26) and sitagliptin (week 52) and was generally well tolerated in patients with type 2 diabetes on metformin.
Clinical trial registry
ClinicalTrials.gov NCT01106677
Funding
This study was supported by Janssen Research & Development, LLC.
ABSTRACT
The fast radio burst (FRB) population is observationally divided into sources that have been observed to repeat and those that have not. There is tentative evidence that the bursts from ...repeating sources have different properties than the non-repeating ones. In order to determine the occurrence rate of repeating sources and characterize the nature of repeat emission, we have been conducting sensitive searches for repetitions from bursts detected with the Australian Square Kilometre Array Pathfinder (ASKAP) with the 64-m Parkes radio telescope, using the recently commissioned Ultra-wideband Low (UWL) receiver system, over a band spanning 0.7–4.0 GHz. We report the detection of a repeat burst from the source of FRB 20190711A. The detected burst is 1 ms wide and has a bandwidth of just 65 MHz. We find no evidence of any emission in the remaining part of the 3.3 GHz UWL band. While the emission bandwidths of the ASKAP and UWL bursts show ν−4 scaling consistent with a propagation effect, the spectral occupancy is inconsistent with diffractive scintillation. This detection rules out models predicting broad-band emission from the FRB 20190711A source and puts stringent constraints on the emission mechanism. The low spectral occupancy highlights the importance of sub-banded search methods in detecting FRBs.
In a vehicular ad hoc network (VANET), the performance of the communication protocol is heavily influenced by the vehicular density dynamics. However, most of the previous works on VANET performance ...modeling paid little attention to vehicle distribution or simply assumed homogeneous car distribution. It is obvious that vehicles are distributed nonhomogeneously along a road segment due to traffic signals and speed limits at different portions of the road, as well as vehicle interactions that are significant on busy streets. In light of the inadequacy, in this paper, we present an original methodology to study the broadcasting performance of 802.11p VANETs with practical vehicle distribution in urban environments. First, we adopt the empirically verified stochastic traffic models, which incorporate the effect of urban settings (such as traffic lights and vehicle interactions) on car distribution and generate practical vehicular density profiles. Corresponding 802.11p protocol and performance models are then developed. When coupled with the traffic models, they can predict broadcasting efficiency, delay, and throughput performances of 802.11p VANETs based on the knowledge of car density at each location on the road. Extensive simulation is conducted to verify the accuracy of the developed mathematical models with the consideration of vehicle interaction. In general, our results demonstrate the applicability of the proposed methodology on modeling protocol performance in practical signalized road networks and shed insights into the design and development of future communication protocols and networking functions for VANETs.
Objectives
To determine the effect of chronic disorders and their co‐occurrence on survival and functioning in community‐dwelling older adults.
Design
Population‐based cohort study.
Setting
...Kungsholmen, Stockholm, Sweden.
Participants
Individuals aged 78 and older examined by physicians four times over 11 years (N = 1,099).
Measurements
Chronic diseases (grouped according to 10 organ systems according to the International Classification of Diseases, Tenth Revision, code) and multimorbidity (≥2 coexisting chronic diseases) were evaluated in terms of mortality, population attributable risk of death, median years of life lost, and median survival time with and without disability (need of assistance in ≥1 activities of daily living).
Results
Approximately one in four deaths were attributable to cardiovascular and one in six to neuropsychiatric diseases. Malignancy was the condition with the shortest survival time (2.5 years). Malignancies and cardiovascular disorders each accounted for approximately 5 years of life lost. In contrast, neurosensorial and neuropsychiatric conditions had the longest median survival time (>6 years), and affected people were disabled for more than half of this time. The most‐prevalent and ‐burdensome condition was multimorbidity, affecting 70.4% of the population, accounting for 69.3% of total deaths, and causing 7.5 years of life lost. Finally, people with multimorbidity lived 81% of their remaining years of life with disability (median 5.2 years).
Conclusion
Survival in older adults differs in length and quality depending on specific conditions. The greatest negative effect at the individual (shorter life, greater dependence) and societal (number of attributable deaths, years spent with disability) level was from multimorbidity, which has made multimorbidity a clinical and public health priority.
We present that the next-generation Enriched Xenon Observatory (nEXO) is a proposed experiment to search for neutrinoless double- β (0νββ) decay in 136Xe with a target half-life sensitivity of ...approximately 1028 yr using 5 × 103 kg of isotopically enriched liquid-xenon in a time projection chamber. This improvement of two orders of magnitude in sensitivity over current limits is obtained by a significant increase of the 136Xe mass, the monolithic and homogeneous configuration of the active medium, and the multiparameter measurements of the interactions enabled by the time projection chamber. Finally, the detector concept and anticipated performance are presented based upon demonstrated realizable background rates.
•Propose firstly a novel frequency-free movable test vehicle for retrieving bridge modal parameters.•Use PU tires to make the test vehicle, which does not show frequency up to 20 Hz.•Using the test ...vehicle in parked state eliminates the pavement roughness effect.•By applying to multi-span bridges, the proposed technique is shown to be accurate, efficient and robust.
Vehicle frequency and pavement roughness are two factors that used to adversely affect the vehicle scanning method for bridges. To tackle these at once, this study proposes the use of a novel frequency-free test vehicle in parked state for bridge measurement. In terms of measurement speed and data quality, the proposed technique is a trade-off between the moving vehicle and fixed sensor techniques, which has the advantage of movability. A test vehicle (single-axle) is considered frequency-free if its frequency is made far larger than those of the bridge of interest. The test vehicle will also be free of pavement roughness if it is used in the parked (non-moving) state. Firstly, based on the bridge-vehicle transmissibility, a test vehicle is designed to have a frequency far beyond those of the bridge of concern, thereby enhancing the bridge frequency peaks. Secondly, lab tests were conducted for two axle-wheel assemblies under ambient vibration. Of interest is that the axle with PU tires shows a favorable random, small and even spectral distribution with no self frequency up to 20 Hz. The PU tires was then assembled as a part of the test vehicle that is self balanced in entity. Finally, the self-made test vehicle was calibrated on a benchmarked bridge and applied to the Xiamen Bus Rapid Transit system. Taking a three-span girder bridge of the system as an example, it was demonstrated that the frequencies, mode shapes and damping ratios of the first four modes of the bridge (flexural or torsional) can be well detected by the frequency-free test vehicle. Compared with the direct measurement, the proposed technique is equally accurate, but more competitive in efficiency and movability.
Abstract
Nickelates are a rich class of materials, ranging from insulating magnets to superconductors. But for stoichiometric materials, insulating behavior is the norm, as for most late transition ...metal oxides. Notable exceptions are the 3D perovskite LaNiO
3
, an unconventional paramagnetic metal, and the layered Ruddlesden-Popper phases R
4
Ni
3
O
10
, (R = La, Pr, Nd). The latter are particularly intriguing because they exhibit an unusual metal-to-metal transition. Here, we demonstrate that this transition results from an incommensurate density wave with both charge and magnetic character that lies closer in its behavior to the metallic density wave seen in chromium metal than the insulating stripes typically found in single-layer nickelates like La
2-
x
Sr
x
NiO
4
. We identify these intertwined density waves as being Fermi surface-driven, revealing a novel ordering mechanism in this nickelate that reflects a coupling among charge, spin, and lattice degrees of freedom that differs not only from the single-layer materials, but from the 3D perovskites as well.
Objectives
Excessive accumulation of adipose tissue may accelerate brain aging, but the underlying mechanisms are poorly understood. Several adiposity indices were proposed to assess obesity, while ...their linkage with brain health in older adults remained unclear. Here we aimed to examine the associations of adiposity indices with global and regional cerebral blood flow (CBF) in older adults, while considering insulin resistance.
Design
This was a cross-sectional population-based study that included older adults derived from the baseline participants in the ongoing Multimodal Interventions to Delay Dementia and Disability in rural China (MIND-China) study.
Setting And Participants
The study included 103 Chinese rural-dwelling older adults (age≥60 years; 69.9% women) who underwent brain magnetic resonance imaging scans.
Methods
We estimated eight adiposity indices based on anthropometric measures. We automatically quantified global and regional CBF using the arterial spin labeling scans. Insulin resistance was assessed using the triglyceride-glucose index and then dichotomized into high and low levels according to the median. Data were analyzed using general linear model and voxel-wise analysis.
Results
Of the eight examined adiposity indices, only higher waist-to-height ratio (WHtR) and body roundness index (BRI) were associated with reduced global CBF (multivariable-adjusted β-coefficients and 95%CI: −1.76; −3.25, −0.27 and −1.77; −3.25, −0.30, respectively) and hypoperfusion in bilateral middle temporal gyri, angular gyri and superior temporal gyri, left middle cingulum and precuneus (P<0.05). There were statistical interactions of WHtR and BRI with levels of insulin resistance on CBF, such that the significant associations of higher WHtR and BRI with lower global and regional CBF existed only in people with high insulin resistance (P<0.05).
Conclusion
Higher WHtR and BRI are associated with cerebral hypoperfusion in older adults, especially in people with high insulin resistance. This may highlight the pathological role of visceral fat in vascular brain aging.
Abstract
Using observations from the Solar Dynamics Observatory’s Atmosphere Imaging Assembly and the Ramaty High Energy Solar Spectroscopic Imager, we present novel measurements of the shear of ...post-reconnection flare loops (PRFLs) in SOL20141218T21:40 and study its evolution with respect to magnetic reconnection and flare emission. Two quasi-parallel ribbons form adjacent to the magnetic polarity inversion line (PIL), spreading in time first parallel to the PIL and then mostly in a perpendicular direction. We measure the magnetic reconnection rate from the ribbon evolution, and also the shear angle of a large number of PRFLs observed in extreme ultraviolet passbands (≲1 MK). For the first time, the shear angle measurements are conducted using several complementary techniques allowing for cross validation of the results. In this flare, the total reconnection rate is much enhanced before a sharp increase in the hard X-ray emission, and the median shear decreases from 60°–70° to 20°, on a timescale of 10 minutes. We find a correlation between the shear-modulated total reconnection rate and the nonthermal electron flux. These results confirm the strong-to-weak shear evolution suggested in previous observational studies and reproduced in numerical models, and also confirm that, in this flare, reconnection is not an efficient producer of energetic nonthermal electrons during the first 10 minutes when the strongly sheared PRFLs are formed. We conclude that an intermediate shear angle, ≤40°, is needed for efficient particle acceleration via reconnection, and we propose a theoretical interpretation.
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