cssi/SciSciGPT-SciSciNet huggingface dataset:
Liquid crystal droplet-based amplification of microvesicles that are shed by mammalian cells

Membrane-derived microvesicles (MVs) shed by cells are being investigated for their role in intercellular communication and as potential biomarkers of disease, but facile and sensitive methods for their analysis do not exist. Here we demonstrate new principles for analysis of MVs that use micrometer-sized droplets of liquid crystals (LCs) to amplify MVs that are selectively captured via antibody-mediated interactions. The influence of the MVs on the micrometer-sized LC droplets is shown to be readily quantified via use of flow cytometry. The methodology was developed using MVs shed by epidermoid carcinoma A431 cells that contain epidermal growth factor receptor (EGFR) as an important and representative example of MVs containing signaling proteins that play a central role in cancer. The LC droplets were found to be sensitive to 106 MVs containing EGFR (relative to controls using isotype control antibody) and to possess a dynamic range of response across several orders of magnitude. Because the 100 nm-sized MVs captured via EGFR generate an optical response in the micrometer-sized LC droplets that can be readily detected by flow cytometry in light scattering mode, the approach possesses significant advantages over direct detection of MVs by flow cytometry. The LC droplets are also substantially more sensitive than techniques such as immunoblotting because the lipid-component of the MVs serves to amplify the antibody-mediated capture of the target proteins in the MVs. Other merits of the approach are defined and discussed in the paper.
COMPARING TRADITIONAL METHODS FOR SELECTING CLASS INTERVALS ON CHOROPLETH MAPS

The most common goal when classing data for choropleth maps is to create homogeneous classes which contain similar data values. None of the four traditional data classing methods examined here (quartile, equal interval, standard deviation, and natural breaks) consistently generalized the experimental data sets into homogeneous classes. These methods were most accurate for data sets with specific distributional characteristics, but none classed all of any type of distribution accurately. Only the optimization method produced reliable and accurate results for all of the experimental data.
Supporting navigation of outdoor shopping complexes for visuallyimpaired users through multi-modal data fusion

Outdoor shopping complexes (OSC) are extremely difficult for people with visual impairment to navigate. Existing GPS devices are mostly designed for roadside navigation and seldom transition well into an OSC-like setting. We report our study on the challenges faced by a blind person in navigating OSC through developing a new mobile application named iExplore. We first report an exploratory study aiming at deriving specific design principles for building this system by learning the unique challenges of the problem. Then we present a methodology that can be used to derive the necessary information for the development of iExplore, followed by experimental validation of the technology by a group of visually impaired users in a local outdoor shopping center. User feedback and other performance metrics collected from the experiments suggest that iExplore, while at its very initial phase, has the potential of filling a practical gap in existing assistive technologies for the visually impaired.
Predicting the effects of military service experience on stressful occupational events in police officers

A review of the literature suggests that law enforcement agencies adopted a paramilitary model of management based on little empirical evidence supporting the suitability of this model. Moreover, relatively little is known about the effects of prior military service experience on the work events experienced by police officers. This paper will examine the effects of prior military service experience on exposure to organizational and field work events, and perceptions of stress among these events. The results show that more military experience did not significantly predict fewer organizational work events and lower perceptions of stress, or more field work events and greater perceptions of stress. More years of police experience and section assignment predicted fewer field work events, although perceptions of stress were not significantly lower. These results are discussed, as they compare with salient demographic variables found to influence work stress in police officers.
Companionship and knot group representations

Abstract A companionship argument is used to give a constructive geometric proof of a key result concerning the knot homomorph problem: Given elements μ and λ in a group G , is there a knot K in S 3 and a surjective representation ρ : π 1 ( S 3 − K )→ G , such that ρ ( m )= μ and ρ ( l )= λ , where m and l are the meridian and longitude of K . The result presented here is that if for some μ that normally generates G , the pair (μ,μ n ) is realizable, where n is the order of H 1 ( G ; Z , then the pair ( v , v n ) is realizable for any normal generator v .
SOME FACTORS WHICH INFLUENCE THE SURFACE OF STONE DIES POURED IN ALGINATE IMPRESSIONS

Abstract Critical examination of stone surfaces which have been poured into alginate impressions reveals: 1. Fixing solutions must be used where they are specified by the manufacturer. 2. Plastic bowls and spatulas for mixing alginate do not produce superior stone surfaces on casts. 3. With the particular alginates tested, placing the poured cast in tap water during the set of the stone produced an inferior surface. 4. The stone cast must not be separated before one hour. 5. There is a difference in the texture of the mix attained from various commercial brands of alginate.
Histologic and ultrastructural features of normal human parietal pericardium.

Abstract Morphologic studies of normal anterior parietal pericardium from seven patients revealed this tissue to be composed of three layers: (1) the serosa, consisting of a surface layer of mesothelial cells and a narrow submesothellal space, (2) the fibrosa, containing variously oriented layers of collagen fibrils and small elastic fibers, and (3) the epipericardial connective tissue layer, containing mainly large coarse bundles of collagen and forming part of the pericardiosternal ligament. Scanning electron microscopic examination is most useful for study of the surface features of pericardial mesothelial cells, which have single cilia and are covered with microvilli. The latter bear friction and increase the surface area for fluid transport. Junctional complexes between adjacent mesothelial cells consist of desmosomes, which reinforce intercellular adhesion and zonulae occludentes, which form permeability barriers. Actin-like filaments (50 A in diameter) are present in microvilli and in immediately subjacent regions of the cells; these filaments mediate changes in cell shape. Intermediate filaments (100 A in diameter) are associated with desmosomes and form bundles in the perinuclear regions; these filaments provide structural support to the cytoplasm.
A laser-based multispectral imaging system for real-time detection of apple fruit firmness

Recent research showed that spectral scattering is useful for assessing the firmness of apple fruit. This paper reports the development of a laser-based multispectral imaging prototype for real-time detection of apple fruit firmness. The prototype consisted of a common aperture multispectral imaging unit, a multi-laser unit, and a belt conveyor, which was able to capture and process spectral scattering images for up to two fruit/s. The multispectral imaging system was tested for detecting the firmness of 'Golden Delicious' and 'Red Delicious' apples when they were moving on the conveyor belt at an imaging speed of one fruit for every two seconds. The original scattering images were corrected by using the newly developed methods of removing noise pixels and incorporating fruit size into the calculation of the scattering distance and intensity. The corrected scattering images were reduced to one-dimensional scattering profiles by radial averaging. The scattering profiles were fitted with a Lorentzian distribution function of four parameters. Multi-linear regression models were developed using the four Lorentzian parameters for the four wavelengths for each apple cultivar, and the models were then used to predict the firmness of validation apples. The multispectral imaging system achieved good firmness predictions with values for the correlation coefficient of 0.85 for 'Golden Delicious' and 0.86 for 'Red Delicious'. The laser-based multispectral imaging system is fast and relatively easy to implement, and it has the potential to meet the requirement for online sorting and grading of apple fruit.
Growth hormone response to growth hormone-releasing factor in selected and control Holstein heifer calves.

Abstract Holstein heifer calves from selected and control lines were treated with growth hormone-releasing factor to determine whether the magnitude of the pituitary growth hormone response is associated with genetic potential for milk yield. Cows in the selected line were bred to highest Predicted Difference milk sires available each year, while control line cows were bred to bulls that were average for 1964 milk production. Eight calves from each line of similar age (206 to 210 days) and weight (205 kg average) were injected intravenously with .1 mg/kg growth hormone-releasing factor. Dams’ first lactation 305-day mature equivalent records were 10,192 ± 495 kg for selected calves and 6,908 ± 376 kg for control calves. Before treatment, GH tended to be higher in selected than control calves (mean ± SE: selected = 7.5 ± 1.8, control = 4.6 ± .4 ng/ml). After injection, peak GH were reached within 20 min and were similar in selected and control calves, averaging 66 ± 16 and 73 ± 13 ng/ml, respectively. Results indicate that the magnitude of the growth hormone response to growth hormone-releasing factor is not related to future performance of dairy calves.
On the effectiveness of on‐line repair policy: quality failure costs perspective

Examines the effectiveness of the line‐stop (on‐line) repair policy over traditional off‐line repair policy through two mathematical models developed based on total quality failure costs (TFC). The proposed models demonstrate that the TFC framework can be a valuable performance measure for evaluating the contribution of the line‐stop repair policy. The computational results also show that the line‐stop policy can bring substantial savings over the off‐line repair policy.
Activity monitor for small animals.

Abstract A photoelectric activity monitor which is easily moveable between cages is described, including a circuit diagram and set-up procedure. In a preliminary study, the number of squares traversed by mice on the cage floor was counted both instrumentally and visually; the instrument count ranged from 105 to 111 per 100 observer counts. In a correlation study, a simulated mouse was moved from square to square both laterally and diagonally while being counted by the instrument and a human observer. They agreed 994 and 977 times respectively in 1000 trials. The instrument should prove particularly useful in studying hyperactive mice, whose activity level is too high for the human observer to count accurately. Behavior monitor patterns may also be studied by feeding the channel outputs to a minicomputer.
Penoscrotal transposition and associated anomalies: report of five new cases and review of the literature.

We present the largest single series of cases (n = 5) of penoscrotal transposition (PST) with carefully documented nongenitourinary/anal anomalies, none of which fell into categories of known syndromes, associations, sequences or chromosome disorders. Several unexpected anomalies were observed including coloboma of the iris and retina, hydrocephalus, microcephaly, diaphragmatic hernia, tracheo-esophageal fistula/esophageal atresia and cleft palate. The most frequent anomalies other than PST were renal defects (100%) such as renal agenesis and dysplasia, imperforate anus (60%), central nervous system anomalies (60%) and preaxial upper limb defects (40%). Cardiovascular defects (atrial septal defect, double aortic arch with vascular ring) were noted in only one case. The surviving patients (3/5) had postnatal growth failure and mental retardation. Our 5 PST patients are compared to 16 well-documented cases from the literature. The overall incidence of various extragenital abnormalities were: renal (90%), mental retarardation (60%), imperforate anus (33%), central nervous system (CNS) anomalies (29%), vertebral defects (29%), preaxial limb defects (24%) and congenital heart disease (19%). PST is a rare heterogenous anomaly, the detection of which should warrant careful clinical evaluation to rule out other anomalies, especially of the urinary system, gastrointestinal tract, upper limbs, craniofacial region and central nervous system. PST may be a localized field defect involving the genitourinary system; however, the wide variety of more distant defects noted in our series and the literature would raise doubt about that assumption. The high frequency of growth deficiency and mental retardation has also not been given due respect as accompanying problems associated with PST. © 1995 Wiley-Liss, Inc.
Tunneling splittings in the water dimer: Further development of the theory

Abstract Energy level expressions are derived for the hydrogen-bonded water dimer complex and some of its deuterated species, using a previously reported internal-axis-method-like formalism developed for high barrier tunneling problems involving several large-amplitude motions. First, the feasibility of various tunneling motions is considered, using a potential surface given by D. F. Coker and R. O. Watts ( J. Phys. Chem. 91 , 2513–2518 (1987)), and three main tunneling paths for (H 2 O) 2 are chosen. We assume that the most feasible path corresponds to a 180° rotation of the acceptor monomer; that the next most feasible path corresponds to a geared-type rotation of the two monomers, leading to an exchange of donor and acceptor monomer roles; and that the third most feasible path corresponds to an exchange of donor hydrogen atoms in the hydrogen bond, accompanied by an umbrella motion of the acceptor monomer. As the second step, the J and K dependence of the purely vibrational tunneling splittings, which arises in the IAM-like formalism because angular momentum is generated during the tunneling motions, is taken into account by computing sets of angles χ, θ, φ for Wigner D ( J ) ( χ , θ , φ ) K , K ′ expressions appearing as factors in the vibrational tunneling matrix elements. Symmetry relations determined for the angles χ, θ, φ greatly simplify the calculations. Finally, the Hamiltonian matrix is set up and diagonalized to obtain the desired energy level expressions (used without proof in an earlier paper treating observed microwave transitions of (H 2 O) 2 ). The J and K dependence of the tunneling splittings arising from the presence of rotational terms in the effective Hamiltonian operator is also discussed, but only for the most symmetric species (H 2 O) 2 and (D 2 O) 2 .
Therapy of bacterial meningitis in children.

The understanding of bacterial meningitis has undergone a major revolution since the first description of epidemic meningitis with a purpuric rash in 1805 [1]. This was followed by further observations of meningococcemia and meningitis, culminating with the isolation of the major meningeal pathogens (Neisseria meningitidis, Streptococcus pneumoniae, and Haemophilus influenzae) in the last two decades of the nineteenth century. Initial treatment of bacterial meningitis in the early years of this century consisted of methods for removal of large volumes of cerebrospinal fluid (CSF) and/or direct CSF instillation of various substances such as dyes and enzymes. The first truly therapeutic modality was introduced by Simon Flexner in 1913 [2], utilizing systemic and intrathecal antimeningococcal antisera; this treatment reduced the mortality rate of meningococcal meningitis from about 80% to 30%. However, major advances in the therapy of bacterial meningitis followed the advent of antimicrobial therapy with the introduction of sulfanilamide, penicillin, and other agents (streptomycin, chloramphenicol) [3,4]. Despite further advances in antibiotic development, the morbidity and mortality from bacterial meningitis remains unacceptably high. In this review, we focus on use of specific antimicrobial agents in the treatment of bacterial meningitis, highlighting recent changes in resistance patterns of meningeal pathogens, and discuss advances in the patho-
The effects of infant births on the sociosexual behavior and hormonal patterns of a cooperatively breeding primate (Cebuella pygmaea)

This study examined changes in the behavioral and hormonal patterns of cooperatively breeding pairs in a primate species with the passing of time and with specific reproductive events. We (1) compared patterns of sexual, agonistic, and affiliative behavior of newly paired pygmy marmosets with the same behavioral patterns immediately after the birth of their first set of infants; (2) determined if postpartum behavioral differences existed between pairs whose infants lived and those whose infants died; and (3) examined whether behavioral patterns changed over the course of ovarian cycles in parous pygmy marmosets as had been documented in nulliparous pairs. The behavior of pairs was recorded during daily half-hour focal samples for 60 days after pairing, and 30 or 60 days after the birth of infants for pairs whose litters died or lived, respectively. Daily urine samples from females during the study were analyzed for luteinizing hormone and pregnanediol glucuronide concentrations to determine dates of ovulation. The results indicated that males consistently altered their sexual behavior and olfactory monitoring of mates during periovulatory periods in the females' cycles both postpairing and postpartum, while similar rates of social and sexual behavior were maintained between the conditions. Sexual behavior occurred throughout the females' ovarian cycles. Peaks in sexual behavior during the periovulatory period in nulliparous pairs disappeared after the birth of infants. Pairs whose infants died showed higher rates of sexual behavior than pairs with surviving infants. Social and sexual behavior may function to maintain the relationship both during and outside of ovulation, especially with the loss of infants. © 1996 Wiley-Liss, Inc.
Ultrasonically sprayed and inkjet printed thin film electrodes for organic solar cells

Abstract Thin film pi-conjugated poly(3,4ethylenedioxythiophene): poly(styrenesulphonate) (PEDOT:PSS) as a hole transport layer on indium tin oxide is a key element in some of the most efficient organic photovoltaic and light emitting devices to date. Films are typically deposited by spincoating, which is not readily scalable. In this paper we investigate the critical parameters for both inkjet and ultrasonic spray deposition of PEDOT:PSS thin films on commercial indium tin oxide as a potentially scalable approach to contact formation. Inkjet parameters investigated include drop spacing and substrate temperature. Ultrasonic spray coating parameters investigated include substrate temperature and solution flow rate. We also show that the ink viscosity has a Newtonian character, making it well suited for inkjet printing. Films were characterized via optical profilometry, sheet resistance and atomic force microscopy. Optimized inkjet printed and ultrasonic sprayed PEDOT:PSS films were then compared to spincast layers in a prototypical bulk heterojunction photovoltaic device employing a poly(3-hexylthiophene) and [6,6]-PCBM (6,6-phenylC61-butric acid-methyl ester) blend as the absorber. Practically all three approaches produced devices of comparable efficiency. Efficiencies were 3.6%, 3.5% and 3.3% for spin, spray and inkjet depositions respectively.
Has the 80-hour work week had an impact on voluntary attrition in general surgery residency programs?

Background This article attempts to assess the effect of the duty-hour limitations implemented in 2003 on voluntary withdrawal of general surgery residents. Study design A questionnaire asked the program directors how many categorical general surgery residents left voluntarily in 2003 to 2004, their training levels, why they left, and where they went. Results were compared with an identical study of 2000 to 2001 and analyzed statistically using chi-square analysis. Results A total of 215 programs (85%) responded, compared with 206 programs (81%) in the previous study. One hundred two programs (48%) reported voluntary attrition of 148 residents, compared with 110 programs (53%) and 167 residents previously. An average of 1.5 residents per program left in programs that reported attrition and 0.7 residents per program in all responders, compared with 1.5 and 0.8 residents in the previous study. In both studies, most programs with attrition lost one (66% [2000 to 2001] and 65% [2003 to 2004]) or two residents (21% [2000 to 2001] and 27% [2003 to 2004]). Most attrition occurred at PGY1 (47%) and PGY2 (28%) levels; a total of 75% of all attrition occurred at these levels, compared with a total of 76% in the previous study. One hundred eleven residents (75%) entered other medical specialties, and 23 (16%) transferred to other general surgery programs, compared with 105 residents (63%) and 40 residents (24%) in the previous study. In both studies, personal issues and work hours/lifestyle were cited as the most common reasons for leaving. In each study, the net loss to general surgery (the number of residents who left voluntarily divided by the total resident population at risk) was 3% for that academic year. Analysis showed no statistically significant difference. Conclusions Rates and patterns of attrition seem to have been unaffected by Accreditation Council for Graduate Medical Education work-hours limitations.
Comment on: Universal quantum circuit for two-qubit transformations with three controlled-NOT gates and Recognizing small-circuit structure in two-qubit operators

Recent papers in Physical Review A have considered small quantum circuit decompositions in terms of a minimal number of controlled-NOT (CNOT) gates. Specifically, we point out errors in the papers by Vidal and Dawson [Phys. Rev. A 69, 010301(R) (2004)] and by Shende et al. [Phys. Rev. A 70, 012310 (2004)].
A selector theorem in Banach spaces

In the present paper, we prove a selector theorem in Banach spaces similar to that of Filippov (Ref. 1), but where the measurability of the selected function follows from a weak upper semicontinuity property.
An Inhalation System for Characterizing Total Lung Deposition of Ultrafine Particles

A new inhalation system is described for characterizing total lung deposition of ultrafine aerosols in humans as a function of particle diameter and breathing pattern. An electrostatic aerosol classifier generated the aerosols and an aerosol electrometer measured their concentrations in inhaled and exhaled air. An inductive plethysmograph measured tidal volumes and was part of a visual feedback system that assured breathing patterns were standardized. A fast-switching solenoid valve system separated inhaled and exhaled air and managed air flow patterns throughout the system. A hygroscopic aerosol, sodium chloride, was used for characterization, but the system is readily adaptable to an insoluble aerosol. The calibration of the system, methods used for data acquisition and analysis, and some of the system's advantages and limitations are discussed. Examples of data are shown to illustrate the system's capability to measure total lung deposition of ultrafine particles.
Detection and Evaluation of Plant Stresses for Crop Management Decisions

The ability to quantitatively assess crop conditions using remotely sensed data would not only improve yield forecasts but would also provide information that would be useful to farm managers in making day-to-day management decisions. Experiments were conducted using ground-based radiometers to relate spectral response to crop canopy characteristics. It was found that radiometrically measured crop temperature, when compared with a reference temperature, was related to the degree of plant stress and could indicate the onset of stress. Reflectance based vegetation indices, on the other hand, were not sensitive to the onset of stress but were useful in evaluating the consequences of stress as expressed in changing quantities of green phytomass. Anatomical and physiological changes occur within plant cells when plants are stressed and increase the amount of reflected radiation. However, canopy geometrical changes may alter the amount of radiation that reaches a radiometer, complicating the interpretation of spectral response to stress. Timeliness, frequency of coverage, andresolution are three factors that must be considered when satellite-based sensors are used to evaluate crop conditions for farm management applications.
Characterizing the effects of natural clouds on scene simulations

In modeling and simulations the importance of the natural environment has always been recognized with regard to its influence on contrast transmission. However, the variability of surface illumination and solar loading due to broken clouds, the resulting impact of dynamic range on recognition, and clouds as backgrounds, along with the traditional influences due to transmission and path radiance, are emerging areas of relevance due to improvements in the modeling of these effects. The Air Force LOWTRAN model has been the traditional choice for multi- waveband analysis of spectral atmospheric effects on systems performance. But this code only has spatially varying effects in the vertical direction. Dynamic range impacts of horizontally variable illumination conditions cannot be addressed. We describe a series of codes designed to allow the linking of predictions of cloud fractions, base heights, layer depths, and layer cloud types with a model to predict the cloud density structure. These results are coupled to a radiative transfer model. We describe the salient features of this physics based model. We then describe the point-to- point calculation method to produce path radiance and transmittance statistics at multi-channel resolution. The weighted spectra are used to describe the effects on a given sensor channel. We further describe the perspective view generation method used to render cloudy scenes from a variety of observer positions. The radiative transfer model is robust in the sense that its results are not limited to low cloud densities. The spectral region covered is the same as that treated by LOWTRAN and LOWTRAN output is used to initialize the upper boundary for incident direct (solar/lunar) and diffuse radiation source and used to determine the background molecular absorption (by modeled layer) of the scattering volume. Typical scattering volumes treated have an 8 km X 8 km footprint and are either 4 km, 8 km, or 16 km high. These volume choices can be used for addition of clouds as scene elements in simulations, usage of the surface illumination information as a positionally varying solar loading or brightness data set, and for path characterization for contrast transmission calculations.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Cytokines secreted by bone-metastatic breast cancer cells alter the expression pattern of f-actin and reduce focal adhesion plaques in osteoblasts through PI3K

Breast cancer frequently metastasizes to bone, resulting in osteolytic lesions. These lesions, formed by activated osteoclasts, cause pain, an increased susceptibility to fractures, and hypercalcemia. It has been shown that breast cancer cells communicate with osteoblasts and subsequently stimulate osteoclast activity; however, little research has focused on understanding the interaction between breast cancer cells and osteoblasts. We recently reported that conditioned medium from MDA-MB-231 breast cancer cells inhibited the differentiation of MC3T3-E1 osteoblasts through the secretion of transforming growth factor beta (TGFbeta). In addition, the breast cancer conditioned medium altered MC3T3-E1 morphology, the pattern of actin stress fibers, and reduced focal adhesion plaques. In the current study, we identified the mechanism used by MDA-MB-231 cells to cause these effects. When MC3T3-E1 osteoblasts were cultured with MDA-MB-231 conditioned medium preincubated with neutralizing antibodies to platelet derived growth factor (PDGF), insulin-like growth factorII (IGFII), and TGFbeta, focal adhesion plaques and actin stress fiber formation were restored. These cytokines were further found to signal through PI3Kinase and Rac. In conclusion, TGFbeta, PDGF, and IGFII might be good therapeutic targets for treating breast cancer-induced osteolytic lesions.
Oestrogen Receptor β: Role in Neurohypophyseal Neurones

The robust expression of oestrogen receptor β (ER-p) in magnocellular vasopressin neurones has focused attention on the role of this receptor and the gonadal steroids in the regulation of vasopressin secretion. Although the effects of gonadal steroids on vasopressin secretion have been the subject of many studies, there is no consensus in the literature as to their role. Possible reasons for the diverse findings are discussed, including diversity in the types, site and level of expression of steroid receptors across species, gender and physiological conditions. The physiological regulation of expression is of particular interest because ER-p mRNA expression in vasopressin neurones is inversely correlated to the osmotic state of the animal. Chronic hyperosmolality inhibits ER-p mRNA expression in magnocellular vasopressin neurones, while chronic hypo-osmolality enhances expression. This is consistent with an inhibitory role for ER-p because hyperosmolality is a potent stimulus for vasopressin secretion, whereas vasopressin secretion is maximally inhibited by chronic hypo-osmolality. An inhibitory role is also indicated by in vitro experiments demonstrating inhibition of osmotically stimulated vasopressin secretion by oestrogen and testosterone, and ER-p mediated inhibition of NMDA-stimulated vasopressin secretion. The challenge remains to elucidate the mechanism of this inhibition, and to understand its significance for maintenance of whole-body fluid and electrolyte homeostasis.
Ontogeny of bioelectric activity in the spinal cord of the chick embryo and its behavioral implications

Abstract Spontaneous spinal cord electrical activity was observed in the lumbosacral region of curarized chick embryos between 5 and 20 days of incubation. Unit activity and polyneuronal burst discharges were found at 5 days, the earliest stage observed. The presence of bursts at 5 days suggests that complex bioelectric activity, which may be multisynaptic in nature, is present very early in development. The burst discharges were also of interest because of their prominence, wide spatial distribution and probable behavioral significance. At 5–6 days, bursts were simple accelerations in unit firing density. At 7–8 days, they increased in duration and complexity due to the appearance of the afterdischarge, a trailing off of unit firing several sec in duration which follows a shorter, higher amplitude, initiating discharge. Burst discharges at 9 and 11 days were some of the longest observed. By 13 days, shorter bursts characteristic of more mature stages were observed. The temporal distribution of bursts also changed with development. At 5–6 days, bursts clustered together in groups of 2–4. By 9 days, burst clusters of regular duration occurred at regular intervals. This regular periodicity was lost at 13 days. The percentage of time that burst discharges were present at a given stage of development increased from a low of 8% at 5 days up to a peak at 13 days of 49%. Activity declined to 14% on day 20, one day before hatching. Because of the many similarities between the amount and periodicity of spontaneous burst activity and embryonic movements at a given stage of development, bursts were proposed as a neural correlate of spontaneous, embryonic motility.
PERMANENT MYXEDEMA: AN UNUSUAL COMPLICATION OF GRANULOMATOUS THYROIDITIS

A patient who suffered three attacks of acute granulomatous thyroiditis eventually experienced permanent myxedema, as proved by failure of thyroidal uptake of I131 to increase after adequate stimulation with TSH. This phenomenon is distinctly unusual, in contrast to the more frequent occurrence of transient myxedema following severe attacks of acute thyroiditis.
Recent Advances in Antithrombotic Therapy for Stroke Prevention in Patients With Atrial Fibrillation

Atrial fibrillation (AF) is the most common sustained cardiac dysrhythmia and patients with AF have a higher risk for stroke than the general population. The prevalence of AF is increasing, which underscores the importance of understanding the therapeutic options available for stroke prevention in the primary care setting. This article examines evidence for the use of novel oral anticoagulant (OAC) therapy, including the direct thrombin inhibitor dabigatran and the activated factor X inhibitors rivaroxaban and apixaban for stroke prevention in patients with AF. Although warfarin therapy is the gold standard for prevention of stroke, its use is associated with significant challenges related to drug-drug and food-drug interactions. Warfarin use also requires frequent blood monitoring to maintain anticoagulation within a narrow therapeutic window. Overall, the novel OACs are as good as, or better than, warfarin therapy for stroke prevention in patients with AF, and they have a comparable or reduced risk of associated major bleeding. In addition, the novel OACs have fewer drug-drug and food-drug interactions and do not require continuous blood monitoring. Integration of the novel OACs into clinical practice offers patients with AF new treatment options, and as therapeutic use of the novel OACs increases, real-world experience will add to our understanding of the value of these agents.
Design of high-order unsymmetrical multiple-loop feedback active filters

Multiple-loop feedback (MF) topologies for the synthesis of high-order active filters are briefly reviewed. Design philosophies, suitable for realising unsymmetrical transfer functions, are discussed. Some practical considerations, which are of importance in designing MF filters, are given.
Effect of mobile phase additives in packed-column subcritical and supercritical fluid chromatography

The effect of mobile phase additives is investigated for a variety of compounds under subcritical and supercritical conditions using packed columns. Retention of hydrogen bond donor/acceptor analytes was found to be more dependent on the presence of mobile phase additives than weak hydrogen bond acceptor analytes. The temperature and pressure of the mobile phase are major factors in the extent of this dependence. Consequently, selectivity between homologous compounds is dependent on both the additive used and the state of the mobile phase. Efficiency is nearly always improved by the presence of mobile phase additives, more so under supercritical conditions than under subcritical conditions. These observations suggest that surface molar excesses of mobile phase additives play a large part in the resulting character of the supercritical chromatographic system.
Estimating individual rater reliabilities

Rating scales have no inherent reliability that is independent of the observers who use them. The often reported interrater reliability is an average of perhaps quite different individual rater reliabilities. It is possible to separate out the individual rater reliabilities given a number of independent raters who observe the same sample of ratees. Under cer tain assumptions, an external measure can replace one of the raters, and individual reliabilities of two independent raters can be estimated. In a somewhat similar fashion, estimates of treatment effects present in ratings by two independent raters can provide the external frame of reference against which dif ferences in their individual reliabilities can be evaluated. Models for estimating individual rater reliabilities are provided for use in selecting, evalu ating, and training participants in clinical research.
Adrenal neuroblastoma in an adult with tumor thrombus in the inferior vena cava

We describe the appearance of an adrenal neuroblastoma associated with tumor thrombus occurring in an adult patient. The tumor measured 14 x 12 x 12 cm, showed heterogeneous signal intensity on both T1-weighted and T2-weighted images, and displayed peripheral nodular enhancement on early post-gadolinium images. Tumor thrombus was identified within the inferior vena cava, which extended into the right atrium.
The stabilizing effects of axial stretching on turbulent vortex dynamics

The evolution and dynamics of vortices in inviscid, incompressible flow under the influence of a deformation field which causes stretching in the axial direction are studied. These vortices are simulated using three-dimensional vortex methods which offer the advantages of having no inherent numerical dissipation and great computational efficiency for short to intermediate times. Two cases in particular are studied: The evolution of a stable, but strongly perturbed vortex, and the evolution of an unstable vortex. In both types of vortices, it is found that the stretching and radial inflow associated with the surrounding deformation field can suppress the growth of disturbances and slow the development of turbulence. This stabilization is even greater than what one would expect from the purely kinematic effects of the deformation field alone, indicating there is a negative feedback on the nonlinear vortex dynamics. The physical mechanisms for stabilization by stretching are discussed, along with potential a...
Dielectric constant of cotton

Abstract A technology derived from the technique for measuring magnetic susceptibility is applied to determine the average dielectric constant of cotton fibers. To a large extent the dielectric constant measurements are independent of the packing fraction and are reasonably independent of the shape of the sample. The results obtained at a frequency of 60 Hz agree well with those obtained by Hearle at 1000 Hz. In this range of frequencies (60–1000 Hz) this dielectric constant of cotton is not expected to change and has a value of seventeen.
Ligand binding studies with microsomal cytochrome P-450 from the housefly, Musca domestica L.

Abstract Optical difference spectra of cytochrome P-450 from abdominal microsomes of the housefly, Musca domestica, were determined using representatives of several recently discovered chemical classes of ligands not previously tested on insects. These included the group IV B dihalides stannous fluoride and germanium iodide, which gave spectra similar to that when carbon monoxide is present and several trivalent oxygen-containing phosphorus compounds which, with the microsome preparation, gave spectra with two peaks in the Soret region, similar to that when ethyl isocyanide is used.
Stricture location in Barrett's esophagus

Twenty-eight patients with Barrett's esophagus were studied and strictures were present in 13. Two strictures were malignant. Of the 11 benign strictures, six were located at the squamocolumnar junction, while five were located below the squamocolumnar junction. Contrary to previous reports, benign esophageal strictures often occur below the squamocolumnar junction in patients with Barrett's esophagus.
Computer simulation of flagellar movement IX. Oscillation and symmetry breaking in a model for short flagella and nodal cilia.

A computer model of flagella in which oscillation results from regulation of active sliding force by sliding velocity can simulate the movements of very short flagella and cilia. Of particular interest are the movements of the short (2–3 µm) nodal cilia of the mammalian embryo, which determine the development of the asymmetry of the internal organs. These cilia must generate a counterclockwise (viewed from base to tip) circling motion. A three-dimensional computer model, with active force generated by a simple mathematical formulation and regulated by sliding velocity, can generate this circling motion if a time delay process is included in the control specification. Without the introduction of a symmetrybreaking mechanism, the computer models start randomly in either direction, and maintain either clockwise or counterclockwise circling. Symmetry can be broken by at least two mechanisms: (1) control of dynein activity on one outer doublet by sliding velocity can be influenced by the sliding velocity experienced on an adjacent outer doublet, or (2) a constant twist of the axoneme caused by an off-axis component of dynein force. This second mechanism appears more reasonable, but its effectiveness is highly dependent upon specifications for the elastic resistances of the model. These symmetry-breaking mechanisms need to be present only at the beginning of circling. With these models, once a circling direction is established, it remains stable even if the symmetry-breaking mechanism is removed.
Synthesis and characterization of monodispersed core-shell spherical colloids with movable cores.

Gold nanoparticles have been conformally coated with amorphous silica (using a sol−gel method) and then an organic polymer (via surface-grafted, atom transfer radical polymerization) to form spherical colloids with a core−double-shell structure. The thickness of silica and polymer shells could be conveniently controlled in the range of tens to several hundred nanometers by changing the concentration of the reagent and/or the reaction time. Selective removal of the silica layer (through etching in aqueous HF) led to the formation of hollow polymer beads containing movable gold cores. This new form of core−shell particles provides a unique system for measuring the feature size and transport property associated with hollow particles. In one demonstration, we showed that the thickness of a closed polymer shell could be obtained by mapping the electrons backscattered from the core and shell. In another demonstration, the plasmon resonance band of the gold cores was used as an optical probe to follow the diffus...
Anatomy of a Modern Marine Sabkha in a Rift Valley Setting, Northwest Gulf of California, Baja California, Mexico: ABSTRACT

An extensive sabkha, 100 by 20 km (62 by 12 mi), caps Holocene siliciclastic tidal flats along the coast of Baja California in the northwest Gulf of California structural trough. This sabkha, bounded on the west by alluvial fans, is a complex of sand flat, saline mud flat, gypsum-halite pan, and supratidal mud flat subenvironments. The sand flat, transitional between the fans and the sabkha, consists of horizontally to wavy laminated sand washed onto the flats by sheetfloods from the fans under upper-flow-regime conditions. The sand flat passes into saline mud flats characterized by massive mud crowded with discoidal gypsum crystals grown within the sediment, destroying the layering. This intrasediment growth of gypsum is driven by evaporative pumping of brine from a shal ow subsurface brine body. A gypsum pan occupies a wide, shallow depression within the saline mud flat. After storm flooding (either marine or meteoric) the pan becomes a temporary saline lake with an algal mat overgrowing a siliciclastic storm layer. Precipitation of gypsum needles from the open lake brine and bottom growth of gypsum prisms produce a gypsum layer that mimics the algal mat topography. Evaporation of the lake leads to (1) vadose diagenetic growth of gypsum that distorts and polygonally disrupts the gypsum layers (2) deposition of a surface halite layer in the center of the pan. These layered pan deposits are the evaporites of the sabkha. Seaward of the saline mud flats are supratidal mud flats underlain by millimeter-thick laminites with deep prism cracks, sheet cracks, an scattered gypsum discoid crystals. Pervasive mud cracking during long periods of nondeposition completely disrupts layering, creating a massive arid "soil." A beach ridge separates this sabkha complex from the burrowed and ripple cross-laminated intertidal sediments. End_of_Article - Last_Page 460------------
Distinct expression patterns for two Xenopus Bar homeobox genes.

The BarH1 and BarH2 homeobox genes are coexpressed in cells of the fly retina and in the central and peripheral nervous systems. The fly Bar genes are required for normal development of the eye and external sensory organs. In Xenopus we have identified two distinct vertebrate Bar-related homeobox genes, XBH1 and XBH2. XBH1 is highly related in sequence and expression pattern to a mammalian gene, MBH1, suggesting that they are orthologues. XBH2 has not previously been identified but is clearly related to the DrosophilaBar genes. During early Xenopus embryogenesis XBH1 and XBH2 are expressed in overlapping regions of the central nervous system. XBH1, but not XBH2, is expressed in the developing retina. By comparing the expression of XBH1 with that of hermes, a marker of differentiated retinal ganglion cells, we show that XBH1 is expressed in retinal ganglion cells during the differentiation process, but is down-regulated as cells become terminally differentiated.
Upon Opening the Black Box and Finding It Empty: Social Constructivism and the Philosophy of Technology:

What do philosophers need to know about technology? What kind of knowledge do we need to have? And how much? Perhaps it is enough simply to have lived in a society in which a wide variety of technologies are in common use. Drawing upon an everyday understanding of such matters, one can move on to develop general perspectives and theories that may enable us to answer important questions about technology in general. The problem is that one's grasp may be superficial, failing to do justice to the phenomena one wants to explain and interpret. One may seize upon a limited range of vaguely understood examples of technical applications-a dam on a river, a robot in a factory, or some other typification-and try to wring universal implications from a sample that is perhaps too small to carry the weight placed upon it. An alternative would be to focus one's attention more carefully, becoming expert in the technical knowledge of a specific field, attaining the deeper understanding of, say, a worker, engineer, or technical professional. Even that may prove limiting, however, because the experience available in one field of practice may not be useful in comprehending the origins, character, and consequences of technical practices in other domains. The sheer multiplicity of technologies in modern society poses serious difficulties for anyone who seeks an overarching grasp of human experience in a technological society. Yet another strategy might be to study particular varieties of technology in a scholarly mode, drawing upon existing histories and contemporary social studies of technological change as one's base of understanding. And one
Visualization of target inspection data at the National Ignition Facility

As the National Ignition Facility continues its campaign to achieve ignition, new methods and tools will be required to measure the quality of the target capsules used to achieve this goal. Techniques have been developed to measure capsule surface features using a phase-shifting diffraction interferometer and Leica Microsystems confocal microscope. These instruments produce multi-gigabyte datasets which consist of tens to hundreds of files. Existing software can handle viewing a small subset of an entire dataset, but none can view a dataset in its entirety. Additionally, without an established mode of transport that keeps the target capsules properly aligned throughout the assembly process, a means of aligning the two dataset coordinate systems is needed. The goal of this project is to develop web based software utilizing WebGL which will provide high level overview visualization of an entire dataset, with the capability to retrieve finer details on demand, in addition to facilitating alignment of multiple datasets with one another based on common features that have been visually identified by users of the system.