cssi/SciSciGPT-SciSciNet huggingface dataset:
High efficiency single pulse doped Al0.60In0.40As/GaInAs/InP HEMTs for Q-band power applications

Single pulse doped, 0.2 mu m-gate Al/sub 0.60/In/sub 0.40/As/GaInAs/InP HEMTs have been fabricated and characterised. The complete process sequence for the HEMTs includes SiN/sub x/ passivation and dry etched via hole fabrication. Power measurements at 44 GHz on a 10*60 mu m/sup 2/ device yielded 225 mW output power, 5 dB associated gain, and 39% power added efficiency. The results indicate that the single pulse doped InP-based HEMTs are suitable for high power applications at Q-band.
Chronic use of symptomatic headache medications

Abstract Chronic use of symptomatic headache medication is believed to be a risk factor for drug-induced chronic headache. This study reports the frequency of chronic use of symptomatic headache medications implicated in drug-induced chronic headache among primary-care headache (PCH) patients and identifies predictors of chronic/frequent use. The design uses a 2-year cohort study of a sample of PCH patients in Group Health Cooperative of Puget Sound, a large health maintenance organization in Seattle, WA. Among 779 PCH patients (aged 18–74 years) interviewed at baseline, 662 (85%) completed both 1- and 2-year follow-up interviews. This study estimates the percent of PCH patients reporting: (1) frequent use of over-the-counter, non-steroidal anti-inflammatory, opioid, sedative-hypnotic, and ergot medications (defined as 14 or more days of use for each class in the prior month), (2) chronic/frequent use of these medications, defined as surpassing criteria for frequent use on at least 2 of the 3 study interviews, and (3) chronic/frequent polypharmacy, defined as chronic/frequent use of 2 or more classes of headache medication. Twenty-one percent of PCH patients were chronic/frequent users of symptomatic headache medications, while 2.6% met study criteria for chronic/frequent polypharmacy. Chronic/frequent use of over-the-counter medications (15.9%) was twice as common as chronic/frequent use of prescription medications (7.7%). Headache days at baseline was the strongest predictor of chronic/frequent medication use. After controlling for baseline persistence and severity, older patients were more likely to be chronic/frequent users of headache medications. The age effect was explained by chronic/frequent use of over-the-counter medications. Chronic/frequent use of symptomatic headache medications was common among PCH patients, especially among patients with persistent headache. Primary-care patients and physicians need to be informed of potential risks of drug-induced chronic headache resulting from chronic/frequent use of prescription and over-the-counter symptomatic headache medications.
Geophysical exploration in polar areas with very low frequency phase variations

Geophysical exploration in polar areas is described with phase variations in very low frequency ground wave propagation from homogeneous and stratified ice to sea water. "Recovery effect" phase variations for mixed paths with homogeneous media are markedly different from those in a stratified media.
Machine learning approaches to improving pronunciation error detection on an imbalanced corpus

In this paper, we investigate the task of phone-level pronunciation error detection as a binary classification problem, the performance of which is heavily affected by the imbalanced distribution of the classes in a manually annotated data set of non-native English. In order to address problems caused by this extreme class imbalance, methods for cost-sensitive learning (weighting inversely proportional to class frequencies) and over-sampling of synthetic instances (SMOTE) are investigated in order to improve classification performance. Experiments using classifiers consisting of features based on acoustic phonetics and word identity demonstrate that these machine learning approaches lead to performance improvements over the baseline system based on the extremely imbalanced data. In addition, several different types of classifiers were compared. Finally, the paper analyzes the robustness of classifier performance across different phones.
Nitric Oxide Synthase Inhibition and Extracellular Glutamate Concentration After Cerebral Ischemia/Reperfusion

Background and Purpose Transient cerebral ischemia in rats results in selective loss of neuronal viability, eg, hippocampal CA1 neurons. The neurochemical variables responsible for this selective v...
Alteration of motor cortex excitability in response to intermittent photic stimulation.

Abstract Objective : To measure the duration of cortical silent period (C-SP) in response to different frequencies of intermittent photic stimulation (IPS). Methods : Ten normal volunteers without a history of seizures were studied. First, using a magnetic stimulator we determined the resting motor threshold (RMT). The C-SP produced by a single magnetic shock at 120% of RMT was measured in the maximally contracted abductor pollicis brevis. C-SP was then measured while subjects were exposed to IPS at 5, 10, 15, 20, 30, 50, and 60 Hz with closed eyes. Results : The average duration of C-SP was 135±33.2 ms with no photic stimulation. This did not change significantly when subjects were exposed to IPS at 5, 10, 15, 20, and 30 Hz. The duration of C-SP, however, decreased significantly at higher frequencies. At 50 Hz it was 116.2±43 ms ( P =0.003) and at 60 Hz it was 112.7±44.6 ms ( P Conclusion : Our findings suggest that motor cortex inhibition is altered in response to IPS at 50 and 60 Hz.
Integrated cell isolation and polymerase chain reaction analysis using silicon microfilter chambers.

Abstract White blood cells are isolated from whole blood in silicon–glass 4.5-μl microchips containing a series of 3.5-μm feature-sized ‘weir-type‘ filters, formed by an etched silicon dam spanning the flow chamber. Genomic DNA targets, e.g., dystrophin gene, can be directly amplified using the polymerase chain reaction (PCR) from the white cells isolated on the filters. This dual function microchip provides a means to simplify nucleic acid analyses by integrating in a single device two key steps in the analytical procedure, namely, cell isolation and PCR.
Effects of Seasonal Operation on the Quality of Water Produced by Public‐Supply Wells

Seasonal variability in groundwater pumping is common in many places, but resulting effects of seasonal pumping stress on the quality of water produced by public-supply wells are not thoroughly understood. Analysis of historical water-quality samples from public-supply wells completed in deep basin-fill aquifers in Modesto, California (134 wells) and Albuquerque, New Mexico (95 wells) indicates that several wells have seasonal variability in concentrations of contaminants of concern. In Modesto, supply wells are more likely to produce younger groundwater with higher nitrate and uranium concentrations during the summer (high) pumping season than during the winter (low) pumping season. In Albuquerque, supply wells are more likely to produce older groundwater with higher arsenic concentrations during the winter pumping season than during the summer pumping season. Seasonal variability in contaminant concentrations in Modesto is influenced primarily by effects of summer pumping on vertical hydraulic gradients that drive migration of shallow groundwater through the aquifer to supply wells. Variability in Albuquerque is influenced primarily by the period of time that a supply well is idle, allowing its wellbore to act as a conduit for vertical groundwater flow and contaminant migration. However, both processes are observed in each study area. Similar findings would appear to be likely in other alluvial basins with stratified water quality and substantial vertical head gradients. Results suggest that even in aquifers dominated by old groundwater, changes to seasonal pumping patterns and/or to depth of well completion can help reduce vulnerability to selected contaminants of either natural or anthropogenic origin.
Interaction with Coxsackievirus and Adenovirus Receptor, but Not with Decay-Accelerating Factor (DAF), Induces A-Particle Formation in a DAF-Binding Coxsackievirus B3 Isolate

Although many coxsackie B viruses interact with decay accelerating factor (DAF), attachment to DAF by itself is not sufficient to initiate infection. We examined the early events in infection that follow virus interaction with DAF, and with the coxsackievirus and adenovirus receptor (CAR). Interaction with soluble CAR in a cell-free system, or with CAR on the surfaces of transfected cells, induced the formation of A particles; interaction with soluble or cell surface DAF did not. The results suggest that CAR, but not DAF, is capable of initiating the conformational changes in the viral capsid that lead to release of viral nucleic acid.
A tutorial on plastic consumer optics

Consumer devices increasingly contain embedded optical systems. Many of these optical systems are based on molded plastic optical elements. This tutorial provides background on the design and manufacture of such systems. Consideration is given to the material issues, manufacturing concerns, and typical design trade-offs and constraints that often accompany plastic consumer optics.
Reaction efficiency of diffusion-controlled processes on finite, aperiodic planar arrays

Abstract Using the theory of finite Markov processes, we show quantitatively that diffusion-limited, reactive events on two finite planar arrays having an aperiodic lattice structure are kinetically advantaged relative to processes on platelets having a regular, hexagonal [6 3 ] structure. The possible relevance of the results obtained to catalytic processes on quasicrystals and zeolite ‘rafts’ is noted.
Physical properties of the bovine encephalitogenic protein; molecular weight and conformation.

— The highly basic encephalitogenic protein isolated from bovine spinal cord was studied by various physicochemical methods: 1 The molecular weight was determined by sedimentation equilibrium, by calculation from the data on sedimentation coefficients and intrinsic viscosities, by measurement of intrinsic viscosity in the presence of concentrated guanidine hydrochloride (according to the method of Tanford, Kawahara and Lapanie, 1967), and by exclusion chromatography on Sephadex G-100 columns. All values obtained were in good agreement and indicated a molecular weight of approximately 18,000–20,000. 2 Studies of sedimentation velocities in the presence and absence of 6 m-guanidine-HCl indicated that there was a significant difference in the values of sedimentation coefficients. 3 The same conditions were applied to the measurements of viscosity; the difference was small but significant. These findings and the magnitude of the intrinsic viscosity suggested that this protein was in a disordered configuration. From these data, it is concluded that the protein was apparently monodispersed, in the presence or absence of the denaturing agent. This protein behaved like a polyelectrolyte in neutral aqueous solution. 4 The measurements of optical rotatory dispersion also confirmed that this protein existed in a disordered configuration.
Exit Block of Artificial Pacemaker Induced by Carotid Sinus Massage

Failure of the pacemaker is a common complication of pacemaker therapy. Identification of the disorder responsible for the failure to pace is often difficult. An increase in myocardial threshold can result in nonconduction of the artificial impulse, particularly near the end of the life of the buttery, when the output of current has started to decine. This report demonstrates such an increase in myocardial resistance which was apparent only upon massage of the carotid sinus.
Identifying events using similarity and context

As part of our work on automatically building knowledge structures from text, we apply machine learning to determine which clauses from multiple narratives describing similar situations should be grouped together as descriptions of the same type of occurrence. Our approach to the problem uses textual similarity and context from other clauses. Besides training data, our system uses only a partial parser as outside knowledge. We present results evaluating the cohesiveness of the aggregated clauses and a brief overview of how this work fits into our overall system.
Metallic nickel as a reagent for the coupling of aromatic and benzylic halides

Abstract The oxidative addition of aromatic and benzylic halides to activated metallic nickel occurred under mild conditions to give the corresponding dehalogenative coupled products in good yields.
Less invasive versus conventional heart valve surgery in patients with severe heart failure

Objective Patients with severe heart failure might benefit from reduced operative trauma, but rarely undergo less-invasive valve surgery. The present study compared the outcomes of less-invasive heart valve surgery with those of complete sternotomy in such patients. Methods From January 1995 to July 2010, 871 patients in New York Heart Association class III or IV underwent valve surgery (aortic or mitral, or both). A less-invasive approach was used in 205. Propensity score matching yielded 185 matched pairs for outcomes comparison adjusted for patient characteristics and 139 pairs adjusted further for individual surgeon. Results Without considering surgeons, myocardial ischemic times (59 ± 27 vs 64 ± 26 minutes, P = .04), cardiopulmonary bypass times (75 ± 35 vs 86 ± 34 minutes, P P = .007) were shorter for less-invasive surgery. Hospital morbidity, mortality (1.6% [3 of 185] vs 2.7% [5 of 185]; P = .5), and long-term survival (53% and 48% at 12 years; P = .3) were similar. After considering the surgeon, these benefits were not apparent; rather, efficiency, safety, and effectiveness were equivalent to those of complete sternotomy. Thus, myocardial ischemic (63 ± 30 vs 62 ± 25 minutes, P = .8) and cardiopulmonary bypass (80 ± 40 vs 81 ± 31 minutes, P = .5) times were similar, as were intensive care unit stay (median, 28 vs 30 hours; P = .09), postoperative complications, in-hospital mortality (2.2% [3 of 139] vs 3.6% [5 of 139]; P = .5), and long-term survival (57% and 53% at 12 years; P = .5). Conclusions In selected patients with severe heart failure, less-invasive valve surgery is a viable option, yielding at least equivalent efficiency, safety, and effectiveness to complete sternotomy. However, achieving these outcomes requires surgeons experienced in less-invasive surgery.
Primary intracranial myxopapillary ependymomas: report of two cases and review of the literature

Myxopapillary ependymoma is a variant of ependymoma occurring almost exclusively in the conus medullaris or filum terminale. Myxopapillary ependymoma found primarily in the brain is extremely rare. Two such cases appearing at the 4th ventricle and cerebral falx are reported. The imaging features of such tumors are a primary cystic mass with strong enhancement at its solid part. Myxopapillary ependymoma should be a possible differential diagnosis when an intracranial cystic tumor is found.
Performance analysis of the signal-code-modulation technique

The authors analyse the performance of a mixed analogue-digital modulation technique called signal code modulation (SCM). The technique is based on the idea of representing the analogue signal by a digital (i.e. quantised) component, and an analogue component consisting of the quantisation error. The combination of these digital and analogue components provides an exact representation of the original signal. Both components are transmitted by the communication system and used to reconstruct an estimate of the signal at the receiver. The presence of the analogue residual allows system performance to improve when excess channel SNR is available. The digital component provides an SNR gain and makes it possible to employ coding to achieve near-error-free transmission. The performance of the SCM method is analysed in some detail.
On the origin of the intracluster light in massive galaxy clusters

We present a pilot study on the origin and assembly history of the ICL for four galaxy clusters at 0.44 0.2 L* and that neither dwarf disruption nor major mergers with the BCG alone can explain the observed level of luminosity and remain consistent with either the observed evolution in the faint end slope of the luminosity function or predictions for the number of BCG major mergers since z=1. Taken together, the results of this pilot study are suggestive of a formation history for these clusters in which the ICL is built-up by the stripping of >0.2 L* galaxies, and disfavor significant contribution to the ICL by dwarf disruption or major mergers with the BCG.
Pressure effects on the flow behavior of sickle (HbSS) red cells in isolated (ex-vivo) microvascular system

Abstract The effect of varying arterial perfusion pressure ( P a ) on flow behavior of human normal (HbAA) and sickle (HbSS) erythrocytes was evaluated in isolated rat mesoappendix vasculature. Red cell velocity ( V rbc ) and wall shear rate in single arterioles (i.d. 20.4 ± 4.5 μm, X and SD) were determined and total peripheral vascular resistance (PRU) calculated. The vasculature initially perfused with Ringer's solution was then perfused with red cells suspended (HCT 2%) in the same medium. At P a of 100 mm Hg, oxy HbSS cells resulted in higher (50%) PRU and lower V rbc (7.1 ± 2.2 mm/sec) and wall shear rates (1800 ± 490 sec −1 ) than those recorded with HbAA cells which show a more rapid microvascular passage, i.e., V rbc (14.4 ± 2.8 mm/sec) and wall shear rates (3810 ± 360 sec −1 ). At the same P a , partial deoxygenation ( P O 2 40 mm Hg) of HbSS cells caused marked (300%) increase in PRU, and decrease in V rbc (3.2 ± 0.9 mm/sec), and wall shear rates (820 ± 440 sec −1 ). During stepwise decrement of P a (100-30 mm Hg), PRU for oxy HbSS cells remains elevated but the overall trend is similar to that for HbAA cells and Ringer's perfusion. At P a of 30 mm Hg, oxy HbSS cells caused some microvascular obstruction. In contrast, with decrement in P a below 80 mm Hg partially deoxy HbSS cells resulted in progressive increase in PRU and drastic decrease in V rbc , coupled with progressive capillary obstruction and stasis. An increased propensity of these cells to cause irreversible vasoocclusion is demonstrated when low-pressure conditions prevail.
Cocaine Induces Nuclear Export and Degradation of Neuronal Retinoid X Receptor-γ via a TNF-α/JNK- Mediated Mechanism

Cocaine abuse represents an immense societal health and economic burden for which no effective treatment currently exists. Among the numerous intracellular signaling cascades impacted by exposure to cocaine, increased and aberrant production of pro-inflammatory cytokines in the CNS has been observed. Additionally, we have previously reported a decrease in retinoid-X-receptor-gamma (RXR-γ) in brains of mice chronically exposed to cocaine. Through obligate heterodimerization with a number of nuclear receptors, RXRs serve as master regulatory transcription factors, which can potentiate or suppress expression of a wide spectrum of genes. Little is known about the regulation of RXR levels, but previous studies indicate cellular stressors such as cytokines negatively regulate levels of RXRs in vitro. To evaluate the mechanism underlying the cocaine-induced decreases in RXR-γ levels observed in vivo, we exposed neurons to cocaine in vitro and examined pathways which may contribute to disruption in RXR signaling, including activation of stress pathways by cytokine induction. In these studies, we provide the first evidence that cocaine exposure disrupts neuronal RXR-γ signaling in vitro by promoting its nuclear export and degradation. Furthermore, we demonstrate this effect may be mediated, at least in part, by cocaine-induced production of TNF-α and its downstream effector c-Jun-NH-terminal kinase (JNK). Findings from this study are therefore applicable to both cocaine abuse and to pathological conditions characterized by neuroinflammatory factors, such as neurodegenerative disease.
Lactosylceramidosis: lactosylceramide galactosyl hydrolase deficiency and accumulation of lactosylceramide in cultured skin fibroblasts.

Fibroblasts were cultured from skin and bone marrow of a patient with an unusual neurovisceral lipid storage disease, characterized by the accumulation of lactosylceramide and a deficiency of lactosylceramide galactosyl hydrolase. The fibroblasts were found to manifest the defect both chemically and enzymically. Biochemical studies of cells cultured from the patient's parents indicated that the disease was inherited in an autosomal recessive manner.
Central nervous system tissue detection in meat from advanced meat recovery systems

Three hundred meat samples, recovered from beef neck- and breast-bones using a conventional advanced meat recovery (AMR) system, the de-sinewed minced meat (DMM10) technology, and hand-boning, were collected and tested for presence of central nervous system tissue (CNST) in meat using an ELISA-based test. Samples were collected at two processing facilities (Est. A and B). Sternum meat was the non-CNST reference (control) - it is distant from brain and spinal cord locations on a carcass, with low likelihood of contamination with CNST. Neckbone meat was recovered from bones obtained from carcasses where the spinal cord was removed manually, Est. B, or using a Jarvis circular hydraulic cord remover saw, Est. A. All samples from AMR, DMM, and hand methods showed lower calculated levels of "risk material" than the stated limit of detection (0.1%) of ELISA kit. There was no apparent difference among these, and use of the Jarvis saw had no perceptible advantage.
Cost utility in the United States of rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone for the treatment of elderly patients with diffuse large B-cell lymphoma

BACKGROUND Findings from the Groupe d'Etude des Lymphomes Adultes LNH 98-5 study showed that rituximab added to combined cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) prolonged progression-free survival and overall survival in adults age ≥ 60 years with diffuse large B-cell non-Hodgkin lymphoma (DLBCL). The current study was conducted to investigate the incremental cost utility of the addition of rituximab to CHOP (R-CHOP) compared with CHOP alone. METHODS Clinical prognosis of the time to disease progression and death was estimated using published evidence from the LNH 98-5 study (n = 399 patients) that was linked mathematically to published long-term outcome data on patients with DLBCL. Drug-acquisition costs were based on published data from formulary pricing sources, and the costs of cancer surveillance and end-of-life care were based on published literature sources. The authors assessed cost utility as the difference in costs between R-CHOP and CHOP divided by the increase in expected overall survival adjusted for quality of life. RESULTS Over 5 years, it was projected that R-CHOP would prolong overall survival by 1.04 years. The mean cumulative cost of CHOP was $3358, and the mean cost of R-CHOP was $17,225, resulting in a cumulative net increase of $13,867. The posttreatment cancer surveillance cost for CHOP was $3950, compared with $5202 for R-CHOP. It was estimated that R-CHOP would have a cost-utility ratio of $19,297 per year of life gained compared with CHOP when adjusted for quality of life. R-CHOP remained cost effective over wide ranges of variables in sensitivity analyses. CONCLUSIONS Compared with CHOP alone, it was predicted that R-CHOP would be cost effective in elderly patients with DLBCL. Cancer 2005. © 2005 American Cancer Society.
Processing of G4 DNA by Dna2 Helicase/Nuclease and Replication Protein A (RPA) Provides Insights into the Mechanism of Dna2/RPA Substrate Recognition

The polyguanine-rich DNA sequences commonly found at telomeres and in rDNA arrays have been shown to assemble into structures known as G quadruplexes, or G4 DNA, stabilized by base-stacked G quartets, an arrangement of four hydrogen-bonded guanines. G4 DNA structures are resistant to the many helicases and nucleases that process intermediates arising in the course of DNA replication and repair. The lagging strand DNA replication protein, Dna2, has demonstrated a unique localization to telomeres and a role in de novo telomere biogenesis, prompting us to study the activities of Dna2 on G4 DNA-containing substrates. We find that yeast Dna2 binds with 25-fold higher affinity to G4 DNA formed from yeast telomere repeats than to single-stranded DNA of the same sequence. Human Dna2 also binds G4 DNAs. The helicase activities of both yeast and human Dna2 are effective in unwinding G4 DNAs. On the other hand, the nuclease activities of both yeast and human Dna2 are attenuated by the formation of G4 DNA, with the extent of inhibition depending on the topology of the G4 structure. This inhibition can be overcome by replication protein A. Replication protein A is known to stimulate the 5'- to 3'-nuclease activity of Dna2; however, we go on to show that this same protein inhibits the 3'- to 5'-exo/endonuclease activity of Dna2. These observations are discussed in terms of possible roles for Dna2 in resolving G4 secondary structures that arise during Okazaki fragment processing and telomere lengthening.
Normal surfaces minimizing weight in a homology class

Abstract In this paper we use elementary combinatorial methods of PL topology to study the intersection of normal surfaces which are least weight in a homology class. Our point of view is that of Jaco and Rubinstein in which a theory of least weight normal surfaces is developed and used to give new proofs of the equivariant sphere theorem and the equivariant loop theorem. Our main result is a generalization of a theorem of Hass: If G is a group acting simplicially on a triangulated orientable 3-manifold M such that Fix(G) is a subcomplex and there exists a nontrivial element α in H2(M;Z) with g ∗ (α)=±α for each gϵG then there exists an equivariantly embedded normal surface F representing the homology class α. The proof of Hass relies on the differentiable theory of minimal surfaces while ours is a simple, self-contained topological proof.
Oxidative stress and antioxidants: exposure and impact on female fertility

Background Reproductive failure is a significant public health concern. Although relatively little is known about factors affecting fertility and early pregnancy loss, a growing body of literature suggests that environmental and lifestyle factors play an important role. There is sufficient evidence to hypothesize that diet, particularly its constituent antioxidants, and oxidative stress (OS) may influence the timing and maintenance of a viable pregnancy. We hypothesize that conditions leading to OS in the female affect time-to-pregnancy and early pregnancy loss. Methods We review the epidemiology of female infertility related to antioxidant defenses and oxidation and examine potential sources of OS from the ovarian germ cell through the stages of human pregnancy and pregnancy complications related to infertility. Articles were identified through a search of the PubMed database. Results Female OS is a likely mediator of conception and threshold levels for OS exist, dependent on anatomic location and stage of preconception. Conclusions Prospective pregnancy studies with dietary assessment and collection of biological samples prior to conception with endpoints of time-to-pregnancy and early pregnancy loss are needed.
Evaluating the Effect of Decompression Surgery on Cerebrospinal Fluid Flow and Intracranial Compliance in Patients with Chiari Malformation with Magnetic Resonance Imaging Flow Studies

OBJECTIVE: To quantify the effect of decompression surgery on craniocervical junction hydrodynamics and on global intracranial compliance (ICC) in patients with Chiari I malformation by use of magnetic resonance measurements of cerebrospinal fluid and blood flow. Studying the effect of decompression surgery may improve our understanding of the pathophysiological characteristics of Chiari I malformation and aid in identifying patients who will benefit from the procedure. METHODS: Twelve patients were studied with a 1.5-T magnetic resonance imaging scanner before and after decompression surgery. Cine phase contrast magnetic resonance images were used to quantify maximum cord displacement, maximum systolic cerebrospinal fluid velocity and volumetric flow rate, and overall ICC. ICC was derived by use of a previously reported method that measures small changes in intracranial volume and pressure that occur naturally with each cardiac cycle. RESULTS: After surgery, changes were documented both in the local hydrodynamic parameters and in ICC. However, only the change in ICC, an average increase of more than 60%, was statistically significant. Increased ICC, which was associated with improved outcome, was measured in 10 of the 12 patients, no significant change was documented in 1 patient, and decreased ICC was measured in 1 patient whose symptoms persisted after surgery. CONCLUSION: An increase in the overall compliance of the intracranial compartment is the most significant and consistent change measured after decompression surgery. Changes in cord displacement, cerebrospinal fluid velocities, and flow in the craniospinal junction were less consistent and less affected by the operation. Thus, ICC may play an important role in the outcome of decompression surgery related to improving symptoms and restoring normal neurological hydrodynamics in patients with Chiari I malformations.
Teaching medical device design using design control.

The design of medical devices requires an understanding of a large number of factors, many of which are difficult to teach in the traditional educational format. This subject benefits from using a challenge-based learning approach, which provides focused design challenges requiring students to understand important factors in the context of a specific device. A course was designed at San Diego State University (CA, USA) that applied challenge-based learning through in-depth design challenges in cardiovascular and orthopedic medicine, and provided an immersive field, needs-finding experience to increase student engagement in the process of knowledge acquisition. The principles of US FDA ‘design control’ were used to structure the students’ problem-solving approach, and provide a format for the design documentation, which was the basis of grading. Students utilized a combination of lecture materials, industry guest expertise, texts and readings, and internet-based searches to develop their understanding of t...
MICROBIAL IMMOBILIZATION AND THE RETENTION OF ANTHROPOGENIC NITRATE IN A NORTHERN HARDWOOD FOREST

To determine the importance of microorganisms in regulating the retention of anthropogenic NO3-, we followed the belowground fate and flow of 5SNO3- in a mature northern hardwood forest, dominated by Acer saccharum Marsh. Total recovery of added t5N (29.5 mg t5N/m2 as NaNO3) in inorganic N, microbial immobilization in forest floor and soil microbial biomass, soil organic matter, and root biomass pools (0-10 cm depth) was 93% two hours following application of the 15NO3- but rapidly dropped to -29% within one month, presumably due to movement of the isotope into other plant tissues or deeper into soil. Microbial immobilization was initially (i.e., at 2 h) the largest sink for 15NO3- (21% in forest floor; 16% in soil microbial biomass). After one month, total t5N recovery varied little (24-18%) throughout the remainder of the growing season, suggesting that the major N transfers among pools occurred relatively rapidly. At the end of the four-month experiment, the main fates of the '5N label were in soil organic matter (7%), root biomass (6%), and N immobilized in forest floor and soil microbial biomass (6%). Temporal changes in the 15N enrichment (atom % excess 15N) of plant and soil pools during the first month of the experiment indicated the dynamic nature of NO3- cycling in this forest. The 15N enrichment of soil microbial biomass and the forest floor significantly increased two hours after isotope additions, suggesting rapid microbial immobilization of NO3-. In contrast, the 15N enrichment of soil organic matter did not peak until day 1, presumably because much of the added 15N cycled through microorganisms before becoming stabilized in soil organic matter, or it directly entered soil organic matter via physical processes. Furthermore, the 15N enrichment of root biomass (<0.5-mm diameter and 0.5- 2.0 mm diameter) was greatest between day 7 and day 28, following significant increases in the 15N enrichment of soil organic matter (day 1) and, more importantly, NH4+ (day 2). From these data we conclude that microorganisms are immediate, short-term sinks for anthropogenic NO3-. Although the long-term fate of NO3- additions to this forest is likely in soil organic matter and plants, the cycling of N through microorganisms appears to be the major short-term factor influencing patterns of NO3- retention in this ecosystem.
Scalable lookahead regular expression detection system for deep packet inspection

Regular expressions (RegExes) are widely used, yet their inherent complexity often limits the total number of RegExes that can be detected using a single chip for a reasonable throughput. This limit on the number of RegExes impairs the scalability of today's RegEx detection systems. The scalability of existing schemes is generally limited by the traditional detection paradigm based on per-character-state processing and state transition detection. The main focus of existing schemes is on optimizing the number of states and the required transitions, but not on optimizing the suboptimal character-based detection method. Furthermore, the potential benefits of allowing out-of-sequence detection, instead of detecting components of a RegEx in the order of appearance, have not been explored. Lastly, the existing schemes do not provide ways to adapt to the evolving RegExes. In this paper, we propose Lookahead Finite Automata (LaFA) to perform scalable RegEx detection. LaFA requires less memory due to these three contributions: 1) providing specialized and optimized detection modules to increase resource utilization; 2) systematically reordering the RegEx detection sequence to reduce the number of concurrent operations; 3) sharing states among automata for different RegExes to reduce resource requirements. Here, we demonstrate that LaFA requires an order of magnitude less memory compared to today's state-of-the-art RegEx detection systems. Using LaFA, a single-commodity field programmable gate array (FPGA) chip can accommodate up to 25n 000 (25 k) RegExes. Based on the throughput of our LaFA prototype on FPGA, we estimate that a 34-Gb/s throughput can be achieved.
Cryogenic performance of a GaAs MMIC distributed amplifier

A three-stage GaAs MMIC distributed amplifier chip which was specially packaged in a two-chip, six-stage amplifier for cryogenic operation from 1 to 10 GHz is discussed. When immersed in liquid nitrogen, a fourfold reduction in amplifier noise is observed over the 4-GHz to 8-GHz frequency range. The cryogenic amplifier package is described, and the test configuration is explained. The reduction in amplifier noise is in agreement with the generally observed scaling with ambient temperature (in Kelvin) for discrete GaAs FET amplifiers. >
US Infant Mortality Trends Attributable to Accidental Suffocation and Strangulation in Bed From 1984 Through 2004: Are Rates Increasing?

Objective Accidental suffocation and strangulation in bed, a subgroup of sudden, unexpected infant deaths, is a leading mechanism of injury-related infant deaths. We explored trends and characteristics of these potentially preventable deaths. Methods In this descriptive study, we analyzed US infant mortality data from 1984 through 2004. To explore trends in accidental suffocation and strangulation in bed and other sudden, unexpected infant deaths, we calculated cause-specific infant mortality rates and estimated proportionate mortality. Sudden, unexpected infant death was defined as a combination of all deaths attributed to accidental suffocation and strangulation in bed, sudden infant death syndrome, and unknown causes. Finally, we examined factors that were reported as contributing to these accidental suffocation and strangulation in bed deaths. Results Between 1984 and 2004, infant mortality rates attributed to accidental suffocation and strangulation in bed increased from 2.8 to 12.5 deaths per 100000 live births. These rates remained relatively stagnant between 1984 and 1992 and increased between 1992 and 2004; the most dramatic increase occurred between 1996 and 2004 (14% average annual increase). In contrast, total sudden, unexpected infant death rates remained stagnant between 1996 and 2004, whereas the proportion of deaths attributed to sudden infant death syndrome declined and to unknown cause increased. Black male infants Conclusions Infant mortality rates attributable to accidental suffocation and strangulation in bed have quadrupled since 1984. The reason for this increase is unknown. Prevention efforts should target those at highest risk and focus on helping parents and caregivers provide safer sleep environments.
Interventions to Promote Sun Protection Behaviors: What Do We Know About the Efficacy of Health- and Appearance-based Messages and the Role of Cognitions and Emotions?

Human behavior has been implicated as a critical component in the development of a number of diseases, including skin cancer. More than 85% of all skin cancers are attributed to over-exposure to the sun, and two primary types of interventions have been utilized to motivate sun protection practices – those that focus on the health consequences (i.e., skin cancer) and those that highlight the negative appearance consequences (i.e., wrinkles and age spots) of sun exposure. Both health-based and appearance-based interventions have been demonstrated to increase awareness of sun exposure dangers and of recommended risk reduction behaviors. Much of the literature examining the efficacy of appearance-based interventions also contains evidence of behavior change in response to such interventions. The role of consciously accessible attitudes and perceptions as mechanisms of behavior change has been extensively examined, and there is evidence that sun protection interventions may promote behavior change in part by altering various health-related cognitions (e.g., perceived susceptibility to skin damage). However, the role of nonconscious mechanisms in the efficacy of sun protection interventions has received little empirical attention. A growing body of literature, primarily in other health contexts, has demonstrated that behavior is sometimes more strongly predicted by emotions than cognitions, and that processes outside of conscious awareness may affect behavior change. It is suggested that both future sun protection interventions, and health promotion theories in general, could benefit from a thorough examination of the role that emotions and autonomic reactions may play in intervention efficacy.
Subdimensional Expansion for Multirobot Path Planning

Abstract Planning optimal paths for large numbers of robots is computationally expensive. In this paper, we introduce a new framework for multirobot path planning called subdimensional expansion, which initially plans for each robot individually, and then coordinates motion among the robots as needed. More specifically, subdimensional expansion initially creates a one-dimensional search space embedded in the joint configuration space of the multirobot system. When the search space is found to be blocked during planning by a robot–robot collision, the dimensionality of the search space is locally increased to ensure that an alternative path can be found. As a result, robots are only coordinated when necessary, which reduces the computational cost of finding a path. We present the M ⁎ algorithm, an implementation of subdimensional expansion that adapts the A ⁎ planner to perform efficient multirobot planning. M ⁎ is proven to be complete and to find minimal cost paths. Simulation results are presented that show that M ⁎ outperforms existing optimal multirobot path planning algorithms.
Chaotic mode competition in parametrically forced surface waves

Vertical forcing of a fluid layer leads to standing waves by means of a subharmonic instability. When the driving amplitude and frequency are chosen to be near the intersection of the stability boundaries of two nearly degenerate modes, we find that they can compete with each other to produce either periodic or chaotic motion on a slow timescale. We utilize digital image-processing methods to determine the time-dependent amplitudes of the competing modes, and local-sampling techniques to study the onset of chaos in some detail. Reconstruction of the attractors in phase space shows that in the chaotic regime the dimension of the attractor is fractional and at least one Lyapunov exponent is positive. The evidence suggests that a theory incorporating four coupled slow variables will be sufficient to account for the mode competition.
Biomolecular Self-Assembly of Quantum-Dot Composites

A biomimetic approach utilizing biomolecular self-assembly was used to tailor quantum-dot composites for use as nonlinear optical media. Yeast tRNA was utilized as an ion-exchange/nucleation site within a polymeric matrix (polyacrylamide). Cadmium ion-exchange and subsequent sulfide precipitation resulted in quantum-dot formation. Illumination of samples with an Argon laser (514 nm) utilizing the Z-scan measurement method resulted in χ 3 values of +3.7 ×10 −6 esu.
Press pundits and Portuguese society

Since the end of the 1980s, the relevance and visibility of media pundits have increased considerably in Portuguese society, due to the institutionalization of the Portuguese democracy, the increased relevance given to public debate and the development of the media sector. This article presents an empirical study regarding the space given over to pundits in mainstream Portuguese print media between 1980 and 2005, a period of significant change in Portugal. It is argued that, seen as a public space, punditry can be conceived as an indicator of the democratization process in Portugal. This study aims to analyze how the changes that took place in Portuguese media and society affected the pundits’ world, their profile and the presence of women in their midst. This study aims to answer several questions: Who are the Portuguese media pundits? Where do they come from? Is this a balanced gender space? What was the impact of structural changes in the media sector and Portuguese society throughout the past 26 years...
Relationship of Test-Day Somatic Cell Score with Test-Day and Lactation Milk Yields

To determine the relationship of test-day (TD) somatic cell score (SCS) to TD and lactation milk yields, 1,320,590 records from Holstein first and second calvings from 1995 through 2002 were examined. All lactations had recorded yield and SCS for at least the first 4 TD. Least square analyses were conducted for yields on TD 2 through 10 within herd and cow. The model included regressions on current TD SCS and mean SCS of all previous TD with separate estimates by parity; effects for parity and calving year were included as well as regression on days in milk on TD 1. Corresponding analyses were conducted without regression on current SCS. An analysis of lactation yield was performed with a similar model and regression on all TD SCS. The SCS was highest most often on TD 1 for parity 1 (22.5%) and on TD 10 for parity 2 (18.5%). Regression of TD milk yield on mean of previous TD SCS was highest during the latter half of lactation (maximum of -0.346 kg/SCS unit on TD 9) for parity 1 and during TD through 7 (maximum of -0.366 kg/SCS unit on TD 4) for parity 2. Regression of TD yield on current TD SCS tended to be larger for later lactation. Regression of lactation yield on TD SCS was negative and important for TD 1 through 6 for parity 1 and for all TD for parity 2. To minimize milk loss, mastitis control is most important immediately pre- and postcalving for parity 1 and throughout lactation for parity 2.
SNDR Considerations for the Minimum Clipping Power Loss Scheme

Orthogonal frequency division multiplexing (OFDM) is a robust wireless communications scheme but has the disadvantage that the symbols have a large dynamic range. Many proposals have been presented for suppressing the large peaks of an OFDM symbol so that higher power efficiencies can be achieved. In this paper, we will examine the recently proposed partial-transmit-sequence-based minimum clipping power loss scheme (MCPLS) and show how it can be generalized to apply to selected mapping (SLM) as well. Additionally, we will relate the clipping power metric in MPCLS to the signal to noise plus distortion ratio (SNDR) that is more commonly used to quantify clipping distortion. Finally, we will derive the SNDR-maximizing parameters that should be used in the new SLM-MPCLS scheme.
Comparison of the loading behavior of self-drilling and predrilled miniscrews throughout orthodontic loading.

Introduction: A predrilled miniscrew, when used as a temporary anchorage device in the infrazygomatic crest of the maxilla, can be displaced under orthodontic loading. The purpose of this retrospective cephalometric study was to compare the loading behavior of predrilled and self-drilling miniscrews placed in the infrazygomatic crest of the maxilla. Methods: The subjects were 32 women who had miniscrews in the infrazygomatic crest of the maxilla as skeletal anchorage for en-masse anterior retraction and intrusion; 16 had predrilled miniscrews, and 16 had the self-drilling type. The miniscrews were all 2 mm in diameter and 10 to 17 mm long. They were loaded with nickel-titanium closed-coil springs 2 weeks after placement. All the miniscrews remained stable, without detectable mobility or loosening, throughout the treatment period. Cephalometric radiographs were taken immediately before force application (T1) and at least 5 months later (T2). The T1 and T2 cephalometric tracings were superimposed to determine whether any displacement of the miniscrews had occurred. Results: The predrilled and self-drilling miniscrews were all significantly displaced in accordance with the force direction of the nickel-titanium coil springs. The amounts of miniscrew displacement were similar between the predrilled and self-drilling miniscrews, and were correlated to the length of the loading period. The displacements were 0.0 to 1.6 mm with extrusion, 1.5 mm with forward or backward tipping at the screw tail, and 1.5 mm with forward tipping at the screw head. Conclusions: The loading behaviors of predrilled and self-drilling miniscrews were similar in the infrazygomatic crest of the maxilla. These miniscrews were all subject to displacement under orthodontic loading, and the amount of the displacement was correlated to the length of the loading period, although they remained stable without detectable mobility or loosening.
MBE growth and characterization of InAs quantum dots on strained GaAs 1-x Sb x buffer layer for application in high efficiency solar cells

We have investigated InAs quantum dots (QDs) on strained GaAsSb barrier layer in different Sb compositions. Use of Sb incorporated barrier layer for QD growth gives better quantum dot properties such as density, lateral size and uniformity. Growing GaAs 0.89 Sb 0.11 results in a doubling of QD density and a 50% decrease in size of the QDs compared to growth on GaAs. Also, size distribution of QDs became narrower after incorporating Sb. These are described based on atomic force microscope (AFM) and its analysis data. X-ray Diffraction (XRD) shows Sb composition as a function of Sb/As flux ratio. On the basis of Reflective High Energy Electron Diffraction (RHEED) oscillation surface morphology of GaAs 1-x Sb x is described as well.