Robust Detection of Ocular Dominance Columns in Humans using High Field HSE BOLD fMRI

The ability to reliably and reproducibility map high resolution functional architecture using fMRI techniques has been a point of debate in animal as well as human studies. Several animal and human studies have successfully mapped high resolution functional organizations, however, the robustness of the phenomenon (i.e. reproducibility and demonstration in multiple subjects), which would certainly improve the credibility of the data, has been a subject of debate. Here we demonstrate the spatial specificity of Hahn spin echo BOLD by robust mapping of ocular dominance columns in humans at the high magnetic field of 7 T

Empyema Thoracis

Epmyema thoracis is associated with high mortality ranging between 6% to 24%. The incidence of empyema is increasing in both children and adults; the cause of this surge is unknown. Most cases of empyema complicate community- or hospital-acquired pneumonia but a proportion results from iatrogenic causes or develops without pneumonia. Parapneumonic effusions (PPE) develop in about one half of the patients hospitalized with pneumonia and their presence cause a four-fold increase in mortality. Three stages in the natural course of empyema have long been described: the exudative, fibrinopurulent, and organizing phases. Clinically, PPE are classified as simple PPE, complicated PPE, and frank empyema. Simple PPE are transudates with a pH > 7.20 whereas complicated PPE are exudates with glucose level <2.2 mmol/l and pH < 7.20. Two guidelines statements on the management of PPE in adults have been published by the American College of Chest Physicians (ACCP) and the British Thoracic Society (BTS). Although they differ in their approach on how to manage PPE, they agree on drainage of the pleural space in complicated PPE and frank empyema. They also recommend the use of intrapleural fibrinolysis and surgical intervention in those who do not show improvement, but the level of evidence for the use of intrapleural fibrinolysis is not high highlighting the need for more research in this area. A recently published large randomized trial has shown no survival advantage with the use of intrapleural streptokinase in patients with pleural infection. However, streptokinase enhances drainage of infected pleural fluid and may still be used in patients with large collection of infected pleural fluid causing breathlessness or ventilatory failure. There is emerging evidence that the combination of intrapleural tPA/DNase is significantly superior to tPA or DNase alone, or placebo in improving pleural fluid drainage in patients with pleural space infection. A guideline statement on the management of PPE in children has been published by the BTS. It recommends the use of antibiotics in all patients with PPE in addition to either video-assisted thoracoscopic surgery (VATS) or tube thoracostomy and intrapleural fibrinolysis. Prospective randomized trials have shown that intrapleural fibrinolysis is as effective as VATS for the treatment of childhood empyema and is a more economic treatment and therefore, should be the primary treatment of choice

Intrapleural therapy in management of complicated parapneumonic effusions and empyema

Empyema thoracis causes high mortality, and its incidence is increasing in both children and adults. Parapneumonic effusions (PPEs) develop in about one-half of patients hospitalized with pneumonia, and their presence increases mortality by about four-fold. PPEs can be divided into simple PPEs, complicated PPEs, and frank empyema. Two guideline statements on the management of PPEs in adults have been published by the British Thoracic Society (BTS) and the American College of Chest Physicians; a third guideline statement published by the BTS focused on management of PPEs in children. The two adult guideline statements recommend drainage of the pleural space in complicated PPEs and frank empyema. They also recommend the use of intrapleural fibrinolysis in those who do not show improvement. The pediatric guideline statement recommends adding intrapleural fibrinolysis to those treated by tube thoracostomy if they have loculated pleural space or thick pus. Published guideline statements on the management of complicated PPEs and empyema in adults and children recommend the use of intrapleural fibrinolysis in those who do not show improvement after pleural space drainage. However, published clinical trial reports on the use of intrapleural fibrinolysis for the treatment of pleural space sepsis suffer from major design and methodologic limitations. Nevertheless, published reports have shown that the use of intrapleural fibrinolysis does not reduce mortality in adults with parapneumonic effusions and empyema. However, intrapleural fibrinolysis enhances drainage of infected pleural fluid and may be used in patients with large collections of infected pleural fluid causing breathlessness or respiratory failure, but a proportion of these patients will ultimately need surgery for definite cure. Intrapleural streptokinase and urokinase seem to be equally efficacious in enhancing infected pleural fluid drainage in adults. In most of the published studies in adults, the use of intrapleural fibrinolysis was not associated with serious side effects. There is emerging evidence that the combination of intrapleural tissue plasminogen activator (tPA) and deoxyribonuclease (DNase) is significantly superior to tPA or DNase alone or placebo in improving pleural fluid drainage in patients with pleural space infection. In children, intrapleural fibrinolysis has not been shown to reduce mortality, but has been shown to enhance drainage of the pleural space and was safe. In addition, two prospective, randomized trials have shown that intrapleural fibrinolysis is as effective as video-assisted thoracoscopic surgery for the treatment of childhood empyema and is a more cost-effective treatment and therefore should be the primary treatment of choice

Pengaruh Tingkat Pendidikan, Masa Kerja dan Motivasi Kerja terhadap Kinerja Karyawan

Tujuan penelitian ini adalah untuk mengetahui pengaruh tingkat pendidikan terhadap kinerja karyawan pada Bank Ekonomi Raharja, mengetahui pengaruh masa kerja terhadap kinerja karyawan pada Bank Ekonomi Raharja, mengetahui pengaruh motivasi kerja terhadap kinerja karyawan pada Bank Ekonomi Raharja, dan mengetahui pengaruh tingkat pendidikan, masa kerja dan motivasi kerja terhadap kinerja karyawan pada PT. Bank Ekonomi Raharja.Teknik pengumpulan data yang digunakan adalah teknik komunikasi tidak langsung dan teknik studi dokumenter. Alat pengumpul data adalah kuesioner. Teknik analisis yang digunakan adalah teknik deskriptif kuantitatif dan teknik analisis regresi berganda. Hasil penelitian menunjukkan bahwa (1) terdapat pengaruh positif dan signifika tingkat pendidikan terhadap kinerja sebesar Pontianak sebesar 34.6% dengan signifikansi 0.00 ≤ 0,05. (2) Masa kerja berpengaruh positif terhadap kinerja sebesar 44.4% dengan signifikansi 0.00 ≤ 0,05. (3) Motivasi kerja berpengaruh positif terhadap kinerja sebesar 44.7% dengan signifikansi 0.00 ≤ 0,05. (4) Tingkat pendidikan, masa kerja dan motivasi kerja berpengaruh positif terhadap kinerja sebesar 72.9% dengan signifikansi 0.00 ≤ 0,05. Kata kunci : pendidikan, masa kerja, motivasi, kinerja Abstrack: The purpose of this study was to determine the effect of education on the performance of employees at Bank Ekonomi Raharja, knowing the effect of tenure on the performance of employees at Bank Ekonomi Raharja, knowing the effect of work motivation on employee performance in Bank Ekonomi Raharja, and determine the effect of education, tenure and work motivation on employee performance in PT. Bank Ekonomi Raharja. The data collection technique used is the technique of indirect communication and techniques of documentary studies. Data collection tool is a questionnaire. The analysis technique used is quantitative descriptive technique and multiple regression analysis techniques. The results showed that (1) there is positive and signifika level of education on the performance of Pontianak amounted to 34.6% at the 0.05 significance ≤ 0:00. (2) The tenure of the positive effect on the performance of 44.4% with a significance of 0.05 ≤ 0:00. (3) Motivation positive effect on the performance of 44.7% with a significance of 0.05 ≤ 0:00. (4) The level of education, years of service and work motivation positive effect on the performance of 72.9% with a significance of 0.05 ≤ 0:00

Sub Millimeter Analysis of Specificity of SE, GE, and ASE BOLD Responses in the Human Visual Cortex

Sub-millimeter spatial resolution applications are becoming of increasing interest in fMRI. Several animal and human studies have successfully mapped high resolution functional organizations. However, it is not known which fMRI technique (which depends on field strength), maximizes contrast to noise as well as specificity to capillaries for sub-millimeter functional mapping. In this work we examine this problem by comparing functional maps, at 0.5mm in plane resolution, of gradient echo BOLD, spin echo BOLD, and asymmetric echo BOLD in human visual cortex at 7 Tesla

Cortical depth dependent functional responses in humans at 7T: improved specificity with 3D GRASE

Ultra high fields (7T and above) allow functional imaging with high contrast-to-noise ratios and improved spatial resolution. This, along with improved hardware and imaging techniques, allow investigating columnar and laminar functional responses. Using gradient-echo (GE) (T2* weighted) based sequences, layer specific responses have been recorded from human (and animal) primary visual areas. However, their increased sensitivity to large surface veins potentially clouds detecting and interpreting layer specific responses. Conversely, spin-echo (SE) (T2 weighted) sequences are less sensitive to large veins and have been used to map cortical columns in humans. T2 weighted 3D GRASE with inner volume selection provides high isotropic resolution over extended volumes, overcoming some of the many technical limitations of conventional 2D SE-EPI, whereby making layer specific investigations feasible. Further, the demonstration of columnar level specificity with 3D GRASE, despite contributions from both stimulated echoes and conventional T2 contrast, has made it an attractive alternative over 2D SE-EPI. Here, we assess the spatial specificity of cortical depth dependent 3D GRASE functional responses in human V1 and hMT by comparing it to GE responses. In doing so we demonstrate that 3D GRASE is less sensitive to contributions from large veins in superficial layers, while showing increased specificity (functional tuning) throughout the cortex compared to GE

High resolution whole brain diffusion imaging at 7 T for the Human Connectome Project

Mapping structural connectivity in healthy adults for the Human Connectome Project (HCP) benefits from high quality, high resolution, multiband (MB)-accelerated whole brain diffusion MRI (dMRI). Acquiring such data at ultrahigh fields (7 T and above) can improve intrinsic signal-to-noise ratio (SNR), but suffers from shorter T2 and T2⁎ relaxation times, increased B1+ inhomogeneity (resulting in signal loss in cerebellar and temporal lobe regions), and increased power deposition (i.e. specific absorption rate (SAR)), thereby limiting our ability to reduce the repetition time (TR). Here, we present recent developments and optimizations in 7 T image acquisitions for the HCP that allow us to efficiently obtain high quality, high resolution whole brain in-vivo dMRI data at 7 T. These data show spatial details typically seen only in ex-vivo studies and complement already very high quality 3 T HCP data in the same subjects. The advances are the result of intensive pilot studies aimed at mitigating the limitations of dMRI at 7 T. The data quality and methods described here are representative of the datasets that will be made freely available to the community in 2015

Multiplexed Echo Planar Imaging for Sub-Second Whole Brain FMRI and Fast Diffusion Imaging

Echo planar imaging (EPI) is an MRI technique of particular value to neuroscience, with its use for virtually all functional MRI (fMRI) and diffusion imaging of fiber connections in the human brain. EPI generates a single 2D image in a fraction of a second; however, it requires 2–3 seconds to acquire multi-slice whole brain coverage for fMRI and even longer for diffusion imaging. Here we report on a large reduction in EPI whole brain scan time at 3 and 7 Tesla, without significantly sacrificing spatial resolution, and while gaining functional sensitivity. The multiplexed-EPI (M-EPI) pulse sequence combines two forms of multiplexing: temporal multiplexing (m) utilizing simultaneous echo refocused (SIR) EPI and spatial multiplexing (n) with multibanded RF pulses (MB) to achieve m×n images in an EPI echo train instead of the normal single image. This resulted in an unprecedented reduction in EPI scan time for whole brain fMRI performed at 3 Tesla, permitting TRs of 400 ms and 800 ms compared to a more conventional 2.5 sec TR, and 2–4 times reductions in scan time for HARDI imaging of neuronal fibertracks. The simultaneous SE refocusing of SIR imaging at 7 Tesla advantageously reduced SAR by using fewer RF refocusing pulses and by shifting fat signal out of the image plane so that fat suppression pulses were not required. In preliminary studies of resting state functional networks identified through independent component analysis, the 6-fold higher sampling rate increased the peak functional sensitivity by 60%. The novel M-EPI pulse sequence resulted in a significantly increased temporal resolution for whole brain fMRI, and as such, this new methodology can be used for studying non-stationarity in networks and generally for expanding and enriching the functional information

Fast spin echo sequences for BOLD functional MRI

At higher field strengths, spin echo (SE) functional MRI (fMRI) is an attractive alternative to gradient echo (GE) as the increased weighting towards the microvasculature results in intrinsically better localization of the BOLD signal. Images are free of signal voids but the commonly used echo planar imaging (EPI) sampling scheme causes geometric distortions, and T2* effects often contribute considerably to the signal changes measured upon brain activation. Multiply refocused SE sequences such as fast spin echo (FSE) are essentially artifact free but their application to fast fMRI is usually hindered due to high energy deposition, and long sampling times. In the work presented here, a combination of parallel imaging and partial Fourier acquisition is used to shorten FSE acquisition times to near those of conventional SE-EPI, permitting sampling of eight slices (matrix 64  ×  64) per second. Signal acquisition is preceded by a preparation experiment that aims at increasing the relative contribution of extravascular dynamic averaging to the BOLD signal. Comparisons are made with conventional SE-EPI using a visual stimulation paradigm. While the observed signal changes are approximately 30% lower, most likely due to the absence of T2* contamination, activation size and t-scores are comparable for both methods, suggesting that HASTE fMRI is a viable alternative, particularly if distortion free images are required. Our data also indicate that the BOLD post-stimulus undershoot is most probably attributable to persistent elevated oxygen metabolism rather than to delayed vascular compliance