231 research outputs found
THE NATURE OF ALBANIAN NASAL-STOP SEQUENCES: PHONETIC, PHONOLOGICAL, SOCIOLINGUISTIC & HISTORICAL BEHAVIOR
The Albanian language is relatively unique among the Indo-European languages with its word initial nasal-stop sequences. Despite broad characterizations, the phonetic, phonological, and sociolinguistic properties of these sequences have not been analyzed with the same rigor as languages with similar sequences. I employ phonetic, perceptual dialectological and historical methods to examine not only how these clusters are employed by speakers in today’s Albanian linguistic landscape, but also to the historical mechanisms and timing of the development of these clusters and their variants within Albanian. With a combined spectral and aerodynamic analysis, I have identified that these clusters are phonemically composed of a discrete nasal and stop, but phonetically are highly variable and do not fit neatly into any partially-nasal category outlined by previous research. In folk linguistics, the variants of these sequences are socially but not phonemically contrastive. This suggests a partially-nasal system in transition, but also challenges our categorical framework for partially-nasal sequences, which is currently uncorroborated by perceptual studies
Measuring Physiological Responses and Emotional Expression during Treatment of Pediatric Feeding Disorders: A Pilot Study
Our study aimed to identify possible associations between measures of physiological and behavioral data in children with feeding disorders during treatment. We found that all children demonstrated an average normal heart rate during the feeding appointments, all children demonstrated a primarily neutral emotion, and that three out of four participants had a brief elevation in heart rate that exceeded the normal range. In the future we would like to further investigate the possible effects of environmental factors at play (i.e., food, electronics) during meals that may correlate with elevations in heart rate.https://digitalcommons.unmc.edu/surp2022/1023/thumbnail.jp
How are oxygen budgets influenced by dissolved iron and growth of oxygenic phototrophs in an iron-rich spring system? Initial results from the Espan Spring in FĂĽrth, Germany
At present most knowledge on the impact of iron on
18O / 16O ratios (i.e. δ18O) of dissolved oxygen
(DO) under circum-neutral conditions stems from experiments carried out
under controlled laboratory conditions. These showed that iron oxidation
leads to an increase in δ18ODO values. Here we present the
first study on effects of elevated Fe(II) concentrations on the δ18ODO in a natural, iron-rich, circum-neutral watercourse. Our
results show that iron oxidation was the major factor for rising dissolved oxygen
isotope compositions in the first 85 m of the system in the cold season
(February) and for the first 15 m during the warm season (May). Further
along the course of the stream, the δ18ODO decreased
towards values known for atmospheric equilibration around +24.6 ‰ during both seasons. Possible drivers for these changes may be reduced iron oxidation, increased atmospheric exchange and
DO production by oxygenic phototrophic algae mats. In the cold season, the
δ18ODO values stabilized around atmospheric equilibrium,
whereas in the warm season stronger influences by oxygenic photosynthesis caused values down to +21.8 ‰. In the warm season
from 145 m downstream of the spring, the δ18ODO
increased again until it reached atmospheric equilibrium. This trend can be
explained by respiratory consumption of DO combined with a relative
decrease in photosynthetic activity and increasing atmospheric influences.
Our study shows that dissolved Fe(II) can exert strong effects on the
δ18ODO of a natural circum-neutral spring system even
under constant supply of atmospheric O2. However, in the presence of
active photosynthesis, with supply of O2 to the system, direct
effects of Fe oxidation on the δ18ODO value become
masked. Nonetheless, critical Fe(II) concentrations may indirectly control
DO budgets by enhancing photosynthesis, particularly if cyanobacteria are
involved.</p
Prognostic factors associated with failure of total elbow arthroplasty
AimsThe aims of this study were to identify and evaluate the current literature examining the prognostic factors which are associated with failure of total elbow arthroplasty (TEA).MethodsElectronic literature searches were conducted using MEDLINE, Embase, PubMed, and Cochrane. All studies reporting prognostic estimates for factors associated with the revision of a primary TEA were included. The risk of bias was assessed using the Quality In Prognosis Studies (QUIPS) tool, and the quality of evidence was assessed using the modified Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) framework. Due to low quality of theevidence and the heterogeneous nature of the studies, a narrative synthesis was used.ResultsA total of 19 studies met the inclusion criteria, investigating 28 possible prognostic factors. Most QUIPS domains (84%) were rated as moderate to high risk of bias. The quality of the evidence was low or very low for all prognostic factors. In low-quality evidence, prognostic factors with consistent associations with failure of TEA in more than one study were: the sequelae of trauma leading to TEA, either independently or combined with acute trauma, and male sex. Severalother studies investigating sex reported no association. The evidence for other factors was of very low quality and mostly involved exploratory studies.ConclusionThe current evidence investigating the prognostic factors associated with failure of TEA is of low or very low quality, and studies generally have a moderate to high risk of bias. Prognostic factors are subject to uncertainty, should be interpreted with caution, and are of little clinical value. Higher-quality evidence is required to determine robust prognostic factors for failure of TEA
The Role of Millimeter-Waves in the Distance Measurement Accuracy of an FMCW Radar Sensor
High-accuracy, short-range distance measurement is required in a variety of industrial applications e.g., positioning of robots in a fully automated production process, level measurement of liquids in small containers. An FMCW radar sensor is suitable for this purpose, since many of these applications involve harsh environments. Due to the progress in the field of semiconductor technology, FMCW radar sensors operating in different millimeter-wave frequency bands are available today. An important question in this context, which has not been investigated so far is how does a millimeter-wave frequency band influence the sensor accuracy, when thousands of distance measurements are performed with a sensor. This topic has been dealt with for the first time in this paper. The method used for analyzing the FMCW radar signal combines a frequency- and phase-estimation algorithm. The frequency-estimation algorithm based on the fast Fourier transform and the chirp-z transform provides a coarse estimate of the target distance. Subsequently, the phase-estimation algorithm based on a cross-correlation function provides a fine estimate of the target distance. The novel aspects of this paper are as follows. First, the estimation theory concept of Cramér-Rao lower bound (CRLB) has been used to compare the accuracy of two millimeter-wave FMCW radars operating at 60 GHz and 122 GHz. In this comparison, the measurement parameters (e.g., bandwidth, signal-to-noise ratio) as well as the signal-processing algorithm used for both the radars are the same, thus ensuring an unbiased comparison of the FMCW radars, solely based on the choice of millimeter-wave frequency band. Second, the improvement in distance measurement accuracy obtained after each step of the combined frequency- and phase-estimation algorithm has been experimentally demonstrated for both the radars. A total of 5100 short-range distance measurements are made using the 60 GHz and 122 GHz FMCW radar. The measurement results are analyzed at various stages of the frequency- and phase-estimation algorithm and the measurement error is calculated using a nanometer-precision linear motor. At every stage, the mean error values measured with the 60 GHz and 122 GHz FMCW radars are compared. The final accuracy achieved using both radars is of the order of a few micrometers. The measured standard deviation values of the 60 GHz and 122 GHz FMCW radar have been compared against the CRLB. As predicted by the CRLB, this paper experimentally validates for the first time that the 122 GHz FMCW radar provides a higher repeatability of micrometer-accuracy distance measurements than the 60 GHz FMCW radar. View Full-Tex
A critical review of the formation of mono- and dicarboxylated metabolic intermediates of alkylphenol polyethoxylates during wastewater treatment and their environmental significance
This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ 2010 Taylor & Francis.Alkylphenoxyacetic acids, the metabolic biodegradation products of alkylphenol ethoxylates, are commonly found in wastewaters and sewage effluents. These persistent hydrophilic derivatives possess intrinsic estrogenic activity, which can mimic natural hormones. Their concentrations increase through the sewage treatment works as a result of biodegradation and biotransformation, and when discharged can disrupt endocrine function in fish. These acidic metabolites represent the dominant alkylphenolic compounds found in wastewater effluent and their presence is cause for concern as, potentially, through further biotransformation and biodegradation, they can act as sources of nonylphenol, which is toxic and estrogenic. The authors aim to assess the mechanisms of formation as well as elimination of alkylphenoxyacetic acids within conventional sewage treatment works with the emphasis on the activated sludge process. In addition, they evaluate the various factors influencing their degradation and formation in laboratory scale and full-scale systems. The environmental implications of these compounds are considered, as is the need for tertiary treatment processes for their removal
A high-level 3D visualization API for Java and ImageJ
BACKGROUND: Current imaging methods such as Magnetic Resonance Imaging (MRI), Confocal microscopy, Electron Microscopy (EM) or Selective Plane Illumination Microscopy (SPIM) yield three-dimensional (3D) data sets in need of appropriate computational methods for their analysis. The reconstruction, segmentation and registration are best approached from the 3D representation of the data set.
RESULTS: Here we present a platform-independent framework based on Java and Java 3D for accelerated rendering of biological images. Our framework is seamlessly integrated into ImageJ, a free image processing package with a vast collection of community-developed biological image analysis tools. Our framework enriches the ImageJ software libraries with methods that greatly reduce the complexity of developing image analysis tools in an interactive 3D visualization environment. In particular, we provide high-level access to volume rendering, volume editing, surface extraction, and image annotation. The ability to rely on a library that removes the low-level details enables concentrating software development efforts on the algorithm implementation parts.
CONCLUSIONS: Our framework enables biomedical image software development to be built with 3D visualization capabilities with very little effort. We offer the source code and convenient binary packages along with extensive documentation at http://3dviewer.neurofly.de
Impaired Brain Dopamine and Serotonin Release and Uptake in Wistar Rats Following Treatment with Carbotplatin
Chemotherapy-induced cognitive impairment, known also as “chemobrain”, is a medical complication of cancer treatment that is characterized by a general decline in cognition affecting visual and verbal memory, attention, complex problem solving skills, and motor function. It is estimated that one-third of patients who undergo chemotherapy treatment will experience cognitive impairment. Alterations in the release and uptake of dopamine and serotonin, central nervous system neurotransmitters that play important roles in cognition, could potentially contribute to impaired intellectual performance in those impacted by chemobrain. To investigate how chemotherapy treatment affects these systems, fast-scan cyclic voltammetry (FSCV) at carbon-fiber microelectrodes was used to measure dopamine and serotonin release and uptake in coronal brain slices containing the striatum and dorsal raphe nucleus, respectively. Measurements were taken from rats treated weekly with selected doses of carboplatin and from control rats treated with saline. Modeling the stimulated dopamine release plots revealed an impairment of dopamine release per stimulus pulse (80% of saline control at 5 mg/kg and 58% at 20 mg/kg) after 4 weeks of carboplatin treatment. Moreover, Vmax, the maximum uptake rate of dopamine, was also decreased (55% of saline control at 5 mg/kg and 57% at 20 mg/kg). Nevertheless, overall dopamine content, measured in striatal brain lysates by high performance liquid chromatography, and reserve pool dopamine, measured by FSCV after pharmacological manipulation, did not significantly change, suggesting that chemotherapy treatment selectively impairs the dopamine release and uptake processes. Similarly, serotonin release upon electrical stimulation was impaired (45% of saline control at 20 mg/kg). Measurements of spatial learning discrimination were taken throughout the treatment period and carboplatin was found to alter cognition. These studies support the need for additional neurochemical and behavioral analyses to identify the underlying mechanisms of chemotherapy-induced cognitive disorders
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