RF system calibration for global Q matrix determination

The use of multiple transmission channels (known as Parallel Transmission, or PTx) provides increased control of the MRI signal formation process. This extra flexibility comes at a cost of uncertainty of the power deposited in the patient under examination: the electric fields produced by each transmitter can interfere in such a way to lead to excessively high heating. Although it is not possible to determine local heating, the global Q matrix (which allows the whole-body Specific Absorption Rate (SAR) to be known for any PTx pulse) can be measured in-situ by monitoring the power incident upon and reflected by each transmit element during transmission. Recent observations have shown that measured global Q matrices can be corrupted by losses between the coil array and location of power measurement. In this work we demonstrate that these losses can be accounted for, allowing accurate global Q matrix measurement independent of the location of the power measurement devices

TINJAUAN KRIMINOLOGIS TERHADAP TINDAK PIDANA INCEST DENGAN KORBAN ANAK(STUDI KASUS DI LAPAS KLAS IIA BANDA ACEH)

ABSTRAKTRI KARUNIA PUTRI AMELIA,TINJAUAN KRIMINOLOGIS TERHADAP 2015 TINDAK PIDANA INCEST DENGAN KORBAN ANAK (STUDI KASUS DI LAPAS KLAS IIA BANDA ACEH)Fakultas Hukum Universitas Syiah Kuala(v,54),pp.,bibl(Dr. DAHLAN ALI., S.H., M.Hum., M.Kn.,)Salah satu kejahatan yang sering terjadi adalah tindak pidana perkosaan. Tindak pidana perkosaan merupakan salah satu dari tindak pidana terhadap kesusilaan. Dalam Bab XIV dalam Buku II KUHP memuat kejahatan terhadap kesusilaan yang tersebar pada pasal 281 hingga 303 KUHP. Di dalamnya yang dimaksud dengan kesusilaan sebagian besar berkaitan dengan seksualitas. Salah satu jenis kelainan seksual adalah hubungan seks yang dilakukan secara paksa bersama seseorang yang masih ada hubungan darah yaitu incest, dan yang biasanya menjadi korban ialah anak-anak. Incest sebagaimana dirumuskan dalam kamus besar bahasa Indonesia adalah hubungan seksual antara orang-orang yang bersaudara dekat yang dianggap melanggar adat, hukum dan agama. Sanksi mengenai incest dengan korban anak dapat dilihat dalam Pasal 81 dan Pasal 82 Undang-Undang No. 23 Tahun 2002 Tentang Perlindungan Anak.Penelitian ini bertujuan untuk menjelaskan faktor penyebab terjadinya tindak pidana incest, dan untuk mengetahui upaya yang perlu dilakukan untuk menanggulangi tindak pidana incest di provinsi Aceh.Untuk memperoleh data dalam penelitian skripsi ini, dilakukan penelitian pustaka (library research) dan penelitian lapangan (field research) yang dilaksanakan di Banda Aceh dengan lokasi penelitian pada Lembaga Pemasyarakatan Klas IIA dengan tipe penelitian deskriptif yaitu menganalisis data yang diperoleh dari studi lapangan dan kepustakaan dengan cara menjelaskan dan menggambarkan kenyataan objek. Hasil penelitian menunjukkan bahwa faktor-faktor penyebab terjadinya tindak pidana incest adalah: Faktor rendahnya pendidikan dan ekonomi, Faktor lingkungan atau tempat tinggal, Faktor alkohol, Faktor kurangnya pemahaman terhadap agama, dan Peranan korban. Penanggulangan tindak pidana incest dapat dilakukan dengan cara mengadakan pelayanan emergency call kepada masyarakat, mengadakan pengedukasian bagi para orang tua, dan juga pembinaan mental kepada pelaku dan korban tindak pidana incest.Disarankan kepada pemerintah agar hendaknya memperbanyak wadah tempat pengaduan untuk masyarakat, serta diadakan penyuluhan hukum agar dapat menumbuhkan kesadaran masyarakat untuk benar-benar mentaati hukum. Selain itu disarankan agar sistem pembuktian dalam kasus perkosaan dapat lebih permudah, khususnya incest.Banda Ace

Functional cardiac MRI in preterm and term newborns.

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A tract-specific approach to assessing white matter in preterm infants.

Diffusion-weighted imaging (DWI) is becoming an increasingly important tool for studying brain development. DWI analyses relying on manually-drawn regions of interest and tractography using manually-placed waypoints are considered to provide the most accurate characterisation of the underlying brain structure. However, these methods are labour-intensive and become impractical for studies with large cohorts and numerous white matter (WM) tracts. Tract-specific analysis (TSA) is an alternative WM analysis method applicable to large-scale studies that offers potential benefits. TSA produces a skeleton representation of WM tracts and projects the group's diffusion data onto the skeleton for statistical analysis. In this work we evaluate the performance of TSA in analysing preterm infant data against results obtained from native space tractography and tract-based spatial statistics. We evaluate TSA's registration accuracy of WM tracts and assess the agreement between native space data and template space data projected onto WM skeletons, in 12 tracts across 48 preterm neonates. We show that TSA registration provides better WM tract alignment than a previous protocol optimised for neonatal spatial normalisation, and that TSA projects FA values that match well with values derived from native space tractography. We apply TSA for the first time to a preterm neonatal population to study the effects of age at scan on WM tracts around term equivalent age. We demonstrate the effects of age at scan on DTI metrics in commissural, projection and association fibres. We demonstrate the potential of TSA for WM analysis and its suitability for infant studies involving multiple tracts

In vivo fluorescence lifetime tomography of a FRET probe expressed in mouse

Förster resonance energy transfer (FRET) is a powerful biological tool for reading out cell signaling processes. In vivo use of FRET is challenging because of the scattering properties of bulk tissue. By combining diffuse fluorescence tomography with fluorescence lifetime imaging (FLIM), implemented using wide-field time-gated detection of fluorescence excited by ultrashort laser pulses in a tomographic imaging system and applying inverse scattering algorithms, we can reconstruct the three dimensional spatial localization of fluorescence quantum efficiency and lifetime. We demonstrate in vivo spatial mapping of FRET between genetically expressed fluorescent proteins in live mice read out using FLIM. Following transfection by electroporation, mouse hind leg muscles were imaged in vivo and the emission of free donor (eGFP) in the presence of free acceptor (mCherry) could be clearly distinguished from the fluorescence of the donor when directly linked to the acceptor in a tandem (eGFP-mCherry) FRET construct

A deformable model for the reconstruction of the neonatal cortex

We present a method based on deformable meshes for the reconstruction of the cortical surfaces of the developing human brain at the neonatal period. It employs a brain segmentation for the reconstruction of an initial inner cortical surface mesh. Errors in the segmentation resulting from poor tissue contrast in neonatal MRI and partial volume effects are subsequently accounted for by a local edge-based refinement. We show that the obtained surface models define the cortical boundaries more accurately than the segmentation. The surface meshes are further guaranteed to not intersect and subdivide the brain volume into disjoint regions. The proposed method generates topologically correct surfaces which facilitate both a flattening and spherical mapping of the cortex

Altered biomechanical stimulation of the developing hip joint in presence of hip dysplasia risk factors

Fetal kicking and movements generate biomechanical stimulation in the fetal skeleton, which is important for prenatal musculoskeletal development, particularly joint shape. Developmental dysplasia of the hip (DDH) is the most common joint shape abnormality at birth, with many risk factors for the condition being associated with restricted fetal movement. In this study, we investigate the biomechanics of fetal movements in such situations, namely fetal breech position, oligohydramnios and primiparity (firstborn pregnancy). We also investigate twin pregnancies, which are not at greater risk of DDH incidence, despite the more restricted intra-uterine environment. We track fetal movements for each of these situations using cine-MRI technology, quantify the kick and muscle forces, and characterise the resulting stress and strain in the hip joint, testing the hypothesis that altered biomechanical stimuli may explain the link between certain intra-uterine conditions and risk of DDH. Kick force, stress and strain were found to be significantly lower in cases of breech position and oligohydramnios. Similarly, firstborn fetuses were found to generate significantly lower kick forces than non-firstborns. Interestingly, no significant difference was observed in twins compared to singletons. This research represents the first evidence of a link between the biomechanics of fetal movements and the risk of DDH, potentially informing the development of future preventative measures and enhanced diagnosis. Our results emphasise the importance of ultrasound screening for breech position and oligohydramnios, particularly later in pregnancy, and suggest that earlier intervention to correct breech position through external cephalic version could reduce the risk of hip dysplasia

Adaptive scan strategies for fetal MRI imaging using slice to volume techniques

© 2015 IEEE.In this paper several novel methods to account for fetal movements during fetal Magnetic Resonance Imaging (fetal MRI) are explored. We show how slice-to-volume reconstruction methods can be used to account for motion adaptively during the scan. Three candidate methods are tested for their feasibility and integrated into a computer simulation of fetal MRI. The first alters the main orientation of the stacks used for reconstruction, the second stops if too much motion occurs during slice acquisition and the third steers the orientation of each slice individually. Reconstruction informed adaptive scanning can provide a peak signal-to-noise ratio (PSNR) improvement of up to 2 dB after only two stacks of scanned slices and is more efficient with respect to the uncertainty of the final reconstruction

Placenta microstructure and microcirculation imaging with diffusion MRI

PURPOSE: To assess which microstructural models best explain the diffusion-weighted MRI signal in the human placenta. METHODS: The placentas of nine healthy pregnant subjects were scanned with a multishell, multidirectional diffusion protocol at 3T. A range of multicompartment biophysical models were fit to the data, and ranked using the Bayesian information criterion. RESULTS: Anisotropic extensions to the intravoxel incoherent motion model, which consider the effect of coherent orientation in both microvascular structure and tissue microstructure, consistently had the lowest Bayesian information criterion values. Model parameter maps and model selection results were consistent with the physiology of the placenta and surrounding tissue. CONCLUSION: Anisotropic intravoxel incoherent motion models explain the placental diffusion signal better than apparent diffusion coefficient, intravoxel incoherent motion, and diffusion tensor models, in information theoretic terms, when using this protocol. Future work will aim to determine if model-derived parameters are sensitive to placental pathologies associated with disorders, such as fetal growth restriction and early-onset pre-eclampsia