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The analysis of multi-phase pharmaceuticals, particularly when similar structures are involved (i.e. polymorphs, salts or hydrates), can often be a difficult task. Historically, x-ray powder diffraction (XRD) and differential scanning calorimetry (DSC) have been utilized to study pharmaceutical samples. Relative to other materials, diffraction data for pharmaceuticals are often complex due to the large number of diffraction maxima caused by the size of the molecule and/or the molecular symmetry. Multi-phase mixtures tend to have a large number of overlapping peaks which can hinder the difftactionist's ability to identify phases and interpret the data. When similar structures are analyzed calorimetrically, their thermal events may severely overlap (as will be shown), preventing accurate interpretation of the data. In addition there are several types of thermal events which may not be related to structural transitions. A common one in pharmaceuticals is the loss of solvent or absorbed (versus molecular) water.
Capillary collimators have found a number of uses in fluorescence, diffraction and other x-ray fields. Most of these applications are realized with single, straight glass capillaries. Focussing of synchrotron x-radiation beams has been shown with tapered capillaries. In addition, numerous straight and bent capillaries, bundled into lens-like optics, offer experimenters many other possibilities for better use of the x-radiation from tubes, synchrotron radiation, and plasma sources or the x-ray intensity collected from samples.
Large area, parallel beams of x-rays are potentially useful in many diffraction, imaging and other x-ray analysis applications. Diffraction, in typical experiments, uses only a small portion of the incident beam that is within a limited “rocking curve” of the crystal capable of diffracting, although the whole crystal may be illuminated by the incident beam. Signal intensity can be increased if the ”whole” crystal can be made to diffract simultaneously. Similarly for imaging, improved results also are possible if divergent beams are replaced with nearly parallel ones. Production of parallel beams of large areal extent has not been simple. Often this meant that the source had to be placed at great distances from the sample, reducing the incident intensity. Sometimes, asymmetric cuts of crystals can be used to increase beam cross-sectional areas.
Production of parallel beams of large area! extent has not been simple. Often this meant that the source had to be placed at great distances from the sample, reducing the incident intensity. Sometimes, asymmetric cuts of crystals can be used to increase beam cross-sectional areas.
It is a well-known result of Sanov (5) that groups of exponent pk (p prime) satisfy the th Engel congruence (definition below). Recently, an alternative proof of this has been given by Glauberman, Krause, and Struik (3). Bruck (2) has conjectured that such groups satisfy the th Engel congruence. In this note we go some way towards proving this.
No previous research has investigated the neural correlates of vocabulary acquisition in second language learners of sign language. The present study investigated whether poor vocabulary knowledge engaged similar prefrontal lexico-semantic regions as seen in unimodal L2 learners. Behavioral improvements in vocabulary knowledge in a cohort of M2L2 learners were quantified. Results indicated that there is significant increase in vocabulary knowledge after one semester, but stabilized in the second semester. A longitudinal fMRI analysis was implemented for a subset of learners who were followed for the entire 10 months during initial sign language acquisition. The results indicated that learners who had poor sign vocabulary knowledge consistently showed greater activation in regions involved in motor simulation, salience, biological motion and spatial processing, and lexico-semantic retrieval. In conclusion, poor vocabulary knowledge requires greater engagement of modality-independent and modality-dependent regions, which could account for behavioral evidence of difficulty in visual phonology processing.
Understanding how language modality (i.e., signed vs. spoken) affects second language outcomes in hearing adults is important both theoretically and pedagogically, as it can determine the specificity of second language (L2) theory and inform how best to teach a language that uses a new modality. The present study investigated which cognitive-linguistic skills predict successful L2 sign language acquisition. A group (n = 25) of adult hearing L2 learners of American Sign Language underwent a cognitive-linguistic test battery before and after one semester of sign language instruction. A number of cognitive-linguistic measures of verbal memory, phonetic categorization skills, and vocabulary knowledge were examined to determine whether they predicted proficiency in a multiple linear regression analysis. Results indicated that English vocabulary knowledge and phonetic categorization skills predicted both vocabulary growth and self-rated proficiency at the end of one semester of instruction. Memory skills did not significantly predict either proficiency measures. These results highlight how linguistic skills in the first language (L1) directly predict L2 learning outcomes regardless of differences in L1 and L2 language modalities.
Accurate wavelengths for highly-ionized L-shell spectra were measured in the 10–16Å region. The purpose being to determine lines in coincidence with L-shell transitions from the elements oxygen, fluorine, and neon. L-shell transitions have been proposed for resonant photopumping of K-shell electrons in these elements to, generate lasing between upper levels in the 40–150 eV region. The current effort improves on and expands the earlier spectroscopic work performed at KMS Fusion, Inc., where possible line coincidences were identified for photoionizing in the 1–3 and 1–4 levels in fluorine. New experimental techniques have led to a wavelength accuracy now believed to be ± 2 mÅ for cases in which adequate calibration lines are available. Exact spectral line matches were found for Mn with the F H,-line at 12.643Å and for both Mn and Cr with the F He line at 14.458Å. The Mn line at 12.643Å has been identified, using ab initio atomic structure calculations, as the 1D2 − 1F3 transition in Be-like Mn XXII. The Mn line emissivity was determined to be 30 MW into 2 steradians for a conversion efficiency of 0.04%. Photopumping with Mn coated gasfilled targets is presently being tried in gain measurement experiments at LLNL.
We wanted to present our experience with the extended endoscopic approach to clival pathology, focusing on cerebrospinal fluid leak and reconstruction challenges.
We examined a consecutive series of 37 patients undergoing the extended endoscopic approach for skull base tumours, 9 patients with clival pathology. Patients were examined for the incidence of post-operative cerebrospinal fluid leak in relation to tumour pathology, location, size, reconstruction and lumbar drain.
The overall incidence of post-operative cerebrospinal fluid leak was 10.8 per cent. Seventy-five per cent of patients who had a post-operative cerebrospinal fluid leak underwent a transclival approach (p < 0.05). All patients with clival pathology who underwent an intradural dissection had a post-operative cerebrospinal fluid leak (p < 0.05).
Post-operative cerebrospinal fluid leak rates after the extended endoscopic approach have improved significantly after advancements including the vascularised nasoseptal flap. Despite this, transclival approaches continue to pose much difficulty. Further investigation is necessary to develop technical improvements that can meet the unique challenges associated with this region.
Children face innumerable challenges following exposure to disasters. To address trauma sequelae, researchers and clinicians have developed a variety of mental health interventions. While the overall effectiveness of multiple interventions has been examined, few studies have focused on the individual components of these interventions. As a preliminary step to advancing intervention development and research, this literature review identifies and describes nine common components that comprise child disaster mental health interventions. This review concluded that future research should clearly define the constituent components included in available interventions. This will require that future studies dismantle interventions to examine the effectiveness of specific components and identify common therapeutic elements. Issues related to populations studied (eg, disaster exposure, demographic and cultural influences) and to intervention delivery (eg, timing and optimal sequencing of components) also warrant attention.
A one-month-old male presented with a palpable right neck mass, which had been noticed 10 days previously. The mass was not perceived to be painful or bothersome to the patient. There was no reported fever or weight loss. He was feeding normally and there was ipsilateral mild torticollis. He was born at 37 weeks by cesarean section due to cardiac decelerations during labor. Imaging evaluation with ultrasound (US) (Fig. 2.1a) demonstrated heterogeneous, mass-like enlargement involving the right inferior sternocleidomastoid muscle (SCM). The mass tapered gently toward the SCM and was surrounded by normal appearing SCM. The fascial planes surrounding the muscle were preserved. There were morphologically normal appearing prominent ipsilateral cervical chain lymph nodes. The lesion did demonstrate moderate internal vascularity on Doppler ultrasound (Fig. 2.1b).
An MRI was also performed in spite of the fact that the US appearance was strongly suggestive of fibromatosis colli. This demonstrated enlargement of the inferior right SCM, with intact surrounding fascial planes. The process was confined to the inferior SCM. There was increased T2 signal and heterogeneous enhancement of the involved muscle (Fig. 2.1c, d, e). There were no calcifications present in the lesion. The MRI findings also supported the diagnosis of fibromatosis colli.
Some birds and mammals have vocal communication systems in which coordination between individuals is important. Examples would include duetting or antiphonal calling in some birds and mammals, rapid exchanges of the same vocalization, and vocal exchanges between paired individuals and other nearby pairs. Mirror neurons may play a role in such systems but become functional only after experience.
Deer populations are increasing throughout the northern hemisphere, and unregulated numbers can jeopardize biodiversity and the economy. These populations are difficult to monitor using visual counts. Estimating densities from surveys of faecal pellets is reliable but time-consuming and thus, if carried out by professionals, expensive. Utilizing volunteers has clear advantages. Based on research from the UK (6 years) and Nova Scotia, Canada (4 years), we investigated the methodological refinements and training required to achieve reliable data when using volunteers. For safety reasons volunteers worked in teams of 5–10 (n = 611) under supervision of scientists. We compared faecal accumulation rate and faecal standing crop surveys using 10 × 10 m quadrats. Both methods produced similar estimates of density, but because of significant time savings and greater volunteer enjoyment we favour faecal standing crop over faecal accumulation rate surveys. Volunteer teams surveyed quadrats significantly faster than a single professional but needed significantly longer to reach and stake out new quadrats. On average, teams found 68% of all droppings. Performance of individuals was affected by training, gender, and willingness and aptitude to survey. After five quadrats men scored significantly higher than women but this difference was reduced after 20 quadrats. Age did not affect performance but willingness and aptitude correlated with ability to find and identify droppings. We conclude that volunteers can monitor deer effectively but that techniques should be modified. The provision of context, training, supervision and verification by a professional are essential. Because of the drain on scientists’ time, cost-effective volunteer deployment is a question of scale.