cssi/SciSciGPT-SciSciNet huggingface dataset:
Boundary layer transition detection by luminescence imaging

In recent experiments we have demonstrated the feasibility of a new approach to boundary layer transition detection. This new approach employs the temperature dependence of certain photoluminescent materials in the form of a surface coating or 'paint' to detect the change in heat transfer characteristics that accompany boundary layer transition. The feasibility experiments were conducted for low subsonic to transonic Mach numbers on two-dimensional airfoil and flat plate configurations. Paint derived transition locations were determined and compared to those obtained from Preston pressure probe measurements. Artificial heating of the models was used to obtain transition temperature signatures suitable for the instrumentation available to us. Initial estimates show, however, that passive kinetic heating at high Mach numbers is a promising alternative.
Determination of manganese in Naiad mollusc shells by neutron activation analysis

Abstract Naiads from two locations 11 river miles apart on the lower Muskingum River in Ohio were studied to determine whether location, calendar year and species could be correlated with the manganese concentration in the shells of the freshwater bivalve molluscs. Neutron activation analysis was used to determine the manganese concentration. The effect of each of these variables on the manganese content of the naiad shells was observed and discussed.
A Comparison of Various Contemporary Methods to Prevent a Wet Cast

Background: Many traditional methods and commercially available products are available to prevent a wet cast, although there is a paucity of literature regarding the optimal strategy. Methods: Using a synthetic leg model, a short leg cast was applied and six different methods were tested. Group A (Glad Press’n Seal wrap), Group B (plastic bag with rubber band), Group C (plastic bag with duct tape), Group D (double plastic bags with duct tape), Group E (CVS Pharmacy Reusable Cast & Wound Protector), and Group F (Dry Corp Dry Pro Large Half Leg Waterproof Cast Cover). Casts were submerged in water for two minutes and were weighed. Each group had ten individual trials. Effectiveness was measured by calculating the amount of water absorption using cast weights before and after submersion. Results: The percentage of water absorption prevention ranged from 62% to 100%, with Groups A and B being the least effective and Groups D, E, and F being the most effective. There was considerable variation in the simplicity of use. Groups C, D, and E were found to be simple to use, with increasing difficulty in Groups A, B, and F. Conclusions: Our findings conclude that the six methods tested are effective in preventing the majority of water saturation. Although abstaining from contact with water is the most prudent approach, if a cast cover is to be used, double plastic bags with duct tape (100% prevention, $10) and the CVS cast protector (100% prevention, $13) are the preferred contemporary methods to prevent a wet cast.
Built-in Self-test and Defect Tolerance in Molecular Electronics-based Nanofabrics

We propose a built-in self-test (BIST) procedure for nanofabrics implemented using chemically assembled electronic nanotechnology. Several fault detection configurations are presented to target stuck-at faults, shorts, opens, and connection faults in nanoblocks and switchblocks. The detectability of multiple faults in blocks within the nanofabric is also considered. We present an adaptive recovery procedure through which we can identify defect-free nanoblocks and switchblocks in the nanofabric-under-test. The proposed BIST, recovery, and defect tolerance procedures are based on the reconfiguration of the nanofabric to achieve complete fault coverage for different types of faults. We show that a large fraction of defect-free blocks can be recovered using a small number of BIST configurations. We also present simple bounds on the recovery that can be achieved for a given defect density. Simulation results are presented for various nanofabric sizes, different defect densities, and for random and clustered defects. The proposed BIST procedure is well suited for regular and dense architectures that have high defect densities.
Spine Cord Injury: An Update

The management of spinal cord injury has advanced significantly over the past decade. The spinal cord injured patient is typically young, and represents a significant public health concern, considering improved survival rates and prolonged disabilities. This update will review recent understanding of spinal cord injury epidemiology and pathophysiology. The treating physician must have an intimate knowledge of the role of surgical and pharmacological management in order to provide optimal care, and these are reviewed herein.
AUDITED SOCIAL RESPONSIBILITY DISCLOSURES

Abstract The disclosure of activities which are of societal concern is mandatory forsome non-profit organizations by virtue of the Single Audit Act of 1984. Weanalyze the desirability of mandating such disclosures for profit oriented entities. Differences in the nature of the contracts that govern the activities of these two types of organizations is discussed. Using societal welfare as a criterion, we conclude that no firm conclusions are warranted before further analysis demonstrates that the net welfare to society will be enhanced by mandating such disclosures.
Emergency treatment of movement disorders

Movement disorder emergencies occur in both hypokinetic and hyperkinetic patients. Prompt recognition of these emergencies is crucial, and diagnosis is based on history and phenomenology. Supportive and temporizing measures must be implemented immediately before disease-specific therapy is begun. For neuroleptic malignant syndrome and related conditions, we recommend a three-tier approach depending on severity, starting with benzodiazepines, dopamine agonists or levodopa, and dantrolene or electroconvulsive therapy. Methylprednisolone pulse therapy also is beneficial for neuroleptic malignant syndrome due to abrupt medication withdrawal in patients with Parkinson’s disease. In treatment of other acute antidopaminergic-induced emergencies, anticholinergics usually suffice. To manage airway obstruction related to movement disorders, we rely on laryngoscopic evaluation to determine whether noninvasive or invasive interventions are needed. Hyperkinetic emergencies are treated individually based on the type of abnormal movements. If an antidopaminergic is needed, we prefer a dopamine depletor to a dopamine receptor blocker because of the risk of tardive syndromes with the latter. When focal hyperkinetic movements dominate the picture, botulinum toxin injection is a useful adjunct to medications.
Simultaneous observation of rotational coherent Stokes Raman scattering and coherent anti-Stokes Raman scattering in air and nitrogen

We report the first simultaneous observation to our knowledge of pure rotational coherent Stokes Raman scattering (CSRS) and coherent anti-Stokes Raman scattering (CARS) using broadband generation and detection. Three-dimensional small-angle phase-matching conditions for CSRS and CARS processes are discussed.
Inconsistencies in information security and digital forensics

Inconsistency in knowledge, information and data is ubiquitous. Inconsistency can be a very effective tool in accomplishing the objectives in information security and digital forensics. In this paper, our focus is on the utilities of inconsistency in those areas: access control lists in firewalls, intrusion detection systems, deception based defense, and digital image forensics. We describe an algorithm for detecting several types of firewall rule inconsistency. Compared with related work, our approach has several salient features. We also highlight various types of inconsistencies in the aforementioned areas. The take-home message is that inconsistency is a very important phenomenon and its utilities can never be underestimated in our endeavors.
Enforcing non-hierarchical access policies by hierarchical key assignment schemes

Without proposing a new key assignment scheme, this paper presents a graph translation procedure so that more complicated non-hierarchical access control policies can be enforced by existing hierarchical key assignment schemes.
The PPARs 2001: it's not over ‘til the fat lady sings

Abstract Recent advances into peroxisome proliferator-activated receptors (PPARs) were presented at a Keystone Symposium entitled ‘The PPARs 2001: A Transcription Odyssey', in Keystone, CO, USA, 4–10 February, 2001.
k-connectivity in random undirected graphs

Abstract This paper concerns vertex connectivity in random graphs. We present results bounding the cardinality of the biggest k-block in random graphs of the Gn,p model, for any constant value of k. Our results extend the work of Erdos and Renyi and Karp and Tarjan. We prove here that Gn,p, with p⩾ c n , has a giant k-block almost surely, for any constant k>0. The distribution of the size of the giant k-block is examined. We provide bounds on this distribution which are very nearly tight. We furthermore prove here that the cardinality of the biggest k-block is greater than n-log n, with probability at least 1−1/(n2log n), for p⩾ c n and c>k+3.
Learned specification of concept neurons.

The referential aspect of a concept can be defined by a disjunction of conjunations of attributes. A single neuron can represent a disjunction of conjunctions of attributes if the assumption that neurons are single-threshold devices is discarded. Instead, one must assume that such concept neurons are composed of hundreds or thousands of (high-threshold) receptive areas, each containing tens or hundreds of synaptic sites. When essentially all of the sites of a receptive area are activated in close temporal contiguity, the receptive area generates a local (spike) response which is assumed to be sufficient to fire the cell body and axon of the neuron. If we assume that all concepts possessed by a single human being can be encoded by single neurons in this manner, there are enough neurons in the human cortex only if we assume that most of these concept neurons are specified by learning. Genetic specification is ruled out by the enormous (infinite?) nember of possible concepts humans appear to be able to learn. Therefore, a speculative neural mechanism is presented regarding how “free” neurons could become specified by learning.
Improving Access Point Association Protocols through Channel Utilization and Adaptive Switching

In this paper, we propose a distributed access point selection scheme by which nodes select an appropriate access point to associate with based on each individual device's channel utilization. We define channel utilization as the ratio of required bandwidth to estimated available bandwidth. By incorporating channel utilization into the access point association protocol, we can effectively reduce unnecessary reassociations and improve upper layer performance such as throughput and packet delivery delay. We have further enhanced our association protocol by using adaptive switching to schedule the switching to neighboring access points (APs), ultimately bringing down the association overhead. When channel utilization is combined with adaptive switching, we observe a significant performance improvement compared to traditional association approaches.
Interplanar magnetic coupling in Cu/Ni composition modulated alloys

Abstract Measurements of the ac susceptibility of composition modulated structures of Cu/Ni have been performed as a function of temperature and magnetic field. A magnetic transition is clearly defined by a peak in the temperature dependence of the ac susceptibility. The peak temperature increases approximately linearly with increasing nickel plane thickness and decreases as the cubic power of the composition modulation. wavelength.
Growth evolution of Si:H prepared with SiH 4 + Si 2 H 6 as studied by real time spectroscopic ellipsometry

The effect of silane + disilane gas mixtures on the growth evolution of hydrogenated silicon (Si:H) thin films have been studied using in situ, real time spectroscopic ellipsometry during plasma enhanced chemical vapor deposition. Growth evolution diagrams were generated for fixed values of S (disilane-to-silane gas ratio) with variable R (hydrogen-to-reactive-gas ratio). Amorphous Si:H (a-Si:H) quality was found to degrade with increasing S, however R could be increased to maintain film quality. The growth rate of optimized a-Si:H material was stable with S, but a wider process parameter range for improved, but not fully-optimized, material was available at lower R with higher rates. Crystallinity was suppressed at higher values of S and lower values of R, but promoted with higher R at increased rates by potentially increasing the initial crystallite nucleation density.
Kindergartners' Mental Addition with Single-Digit Combinations

relationship (adding with zero leaves a number unchanged) rather than from the practice and memorization of individual facts. The results indicate that mental-arithmetic errors, changes in error patterns, and mastering some simple facts cannot be explained entirely as a function of practice. How do young children determine the sums of single-digit combinations when they have not learned their correct answers and may not compute them? Do they resort to guessing, retrieving learned errors, or estimating? How do children then master the combinations involving zero and one? Association- and schema-based views suggest fundamentally different answers to these questions.
In Defence of Defensive Warfare

We All Fall Down The Prospect of Biological and Chemical Warfare. By Robin Clarke. Pp. xiii + 201. (Allen Lane: London, 1968.) 35s.
A chronometric study of mental paper folding

Abstract On each trial Ss viewed one of the patterns of six connected squares that result when the faces of a cube are unfolded onto a flat surface. The Ss tried, as rapidly as possible, to decide whether two arrows, each marked on an edge of a (different) square, would or would not meet if the squares were folded back up into the cube. The time required to make such decisions increased linearly (from 2 to about 15 sec) with the sum of the number of squares that would be involved in each fold, if those folds were actually performed physically.
Controlled trial of hydroxychloroquine and d‐penicillamine singly and in combination in the treatment of rheumatoid arthritis

A 2-year, controlled, double-blind trial of D-penicillamine and hydroxychloroquine either alone or in combination was conducted on patients with progressive rheumatoid arthritis. The group given D-penicillamine alone improved most, but a linear fall-off in efficacy occurred. Surprisingly, the group receiving combination drug therapy did not fare as well as the group receiving D-penicillamine therapy. A subset of patients receiving hydroxychloroquine therapy had prolonged benefit. Toxicity, though not uncommon, was generally not severe.
Ethnic Politics, Mediation, and Conflict Resolution: The Guyana Experience:

Coercive and elitist approaches to political control in post-colonial states like Guyana have often proved counterproductive with respect to resolving ethno-political conflicts in these parts. In Guyana, this contradiction is usually manifested in terms of the escalation of legitimate political competition into overtly violent ethno-political violence and polarization, and reinforced by the consequent devaluation of the more democratic or pacific alternatives to conflict resolution such as mass or grass-roots participation, intergroup negotiations, and third-party mediation. Recurring debates between Cultural Pluralists and Marxists on this issue have so far failed to shed light on the prospects for the more pacific approaches to conflict resolution. Closer analytic scrutiny of actual ethno-political conflict events in Guyana between 1948 and 1999 leads to the understanding that such conflicts derive largely from what is termed a continual crisis of political legitimacy reflected in the inequities of political representation and economic resource distribution across groups. The more democratic or pacific approaches are here suggested as most appropriate for the resolution of the political legitimation crisis and the ultimate realization of a sustainable peace among the diverse groups in the Guyana political system.
Biodiversity and invasibility in grassland microcosms

In the years since Charles Elton proposed that more diverse communities should be less susceptible to invasion by exotic species, empirical studies have both supported and refuted Elton's hypothesis. Here, I use grassland community microcosms to test the effect of functional diversity on the success of an invasive annual weed (Centaurea solstitialis L.). I found that high functional diversity reduced the success of Centaurea by reducing resource availability. An equally important, but unstudied, question is whether diversity can buffer a community against the impacts of invasive species. In this experiment, although species diversity (independent of functional diversity) did not affect the success of the invader, the invader suppressed growth of species-poor communities more strongly. Invasion of Centaurea also increased summer evapotranspiration in species-poor communities. These results suggest that loss of species diversity alone does not affect community invasibility, but that communities with fewer species may be more likely to decline as a consequence of invasion.
A sims study of ion-assisted etching mechanisms; adsorbed fluorine on Si removed by ion bombardment

Abstract Secondary ion mass spectrometry (SIMS), previously calibrated using quartz crystal microbalance (QCM) methods, has been used to measure the cross-section for ion-bombardment-induced removal of fluorine adsorbed on silicon. Large (100 A2) cross-sections have been found at high fluorine coverages. It is believed that ion bombardment of the adsorbed fluorine layer forms relatively large quantities of volatile silicon fluorides which spontaneously desorb from the surface. At low fluorine coverages, where the cross-sections are much smaller (5–10 A2), there is insufficient fluorine to form volatile silicon fluorides and the adsorbed fluorine must be removed primarily by physical sputtering. This phenomenon of ion-bombardment-induced gasification or ion-induced clearing of adsorbed layers is believed to be responsible for the ion-enhanced gas-surface chemistry observed in directed beam studies involving fluorine and silicon. Furthermore, it is suspected that many of the observations of anisotropic etching in reactive gas glow discharges may be caused by this process.
Palladium(II), Magnesium(II), and Barium(II) Nitrate Combinations for Matrix Modification in Electrothermal Atomic Absorption Measurement of Total Selenium in Human Urine

Abstract Electrothermal atomic absorption spectrometry with a temperature-stabilizing platform and palladium(II) nitrate-magnesium nitrate-barium nitrate matrix modifier combination was used to measure total selenium concentrations in 0.5-ml samples of human urine. The method was validated by analysis of desiccated, standard urine samples (SRM 2670) from NIST. The peak height response was linear from 0 to 150 μg Se/liter urine with a sensitivity of 0.001 absorbance unit/μg Se/liter and a detection limit of 6 μg Se/liter (P = 0.05) for a single measurement. Total urinary selenium concentrations and urine volumes of 24-h samples from 28 healthy adult subjects on self-selected diets and living in San Angelo, Texas were measured. Daily total urinary excretions of 16 male and 12 female subjects (mean ± SD) were 28 ± 26 and 34 ± 25 μg Se/day, respectively. A single subject taking 300 μg Se/day in the form of aqueous SeO2 as a dietary supplement excreted 232 μg Se/day. The unsupplemented subjects′ daily selenium excretions correspond to a mean dietary intake of approximately 60 μg/day.
An embodied computational model of social referencing

Social referencing is the tendency to use the emotional reaction of another to help form one's own affective appraisal of a novel situation, which is then used to guide subsequent behavior. It is an important form of emotional communication and is a developmental milestone for human infants in their ability to learn about their environment through social means. In this paper, we present a biologically-inspired computational model of social referencing for our expressive, anthropomorphic robot that consists of three interacting systems: emotional empathy through facial imitation, a shared attention mechanism, and an affective memory system. This model presents opportunities for understanding how these mechanisms might interact to enable social referencing behavior in humans.
Delay-limited throughput of cooperative multiple access channels with hybrid-ARQ

This paper considers a two-user, quasi-static multiple access channel with hybrid-automatic repeat request (HARQ) and user cooperation. The protocol uses incremental redundancy HARQ packet transmission from both users until at least one userpsilas packet is successfully decoded. If one userpsilas packet is successful before the other, the successful user begins to act as a relay for the other user until packet success or until a maximum number of HARQ rounds L, where L represents the packet delay constraint. The performance of this cooperative multiple access channel is evaluated using the delay-limited throughput, defined as a measure of the throughput of an arbitrary packet, as well as the conventional long-term average throughput. The throughput metrics depend on each userpsilas individual outage probability, which is approximately equal to the userpsilas packet error probability as a function of the number of HARQ rounds. Compared to no user cooperation, this cooperative protocol provides significantly higher throughputs, with increasing gains for more stringent quality-of-service (QoS) constraints.
Large neighborhood search for dial-a-ride problems

Dial-a-Ride problems (DARPs) arise in many urban transportation applications. The core of a DARP is a pick and delivery routing with multiple vehicles in which customers have ride-time constraints and routes have a maximum duration. This paper considers DARPs for which the objective is to minimize the routing cost, a complex optimization problem which has been studied extensively in the past. State-of-the-art approaches include sophisticated tabu search and variable neighborhood search. This paper presented a simple constraint-based large neighborhood search, which uses constraint programming repeatedly to find good reinsertions for randomly selected sets of customers. Experimental evidence shows that the approach is competitive in finding best-known solutions and reaches high-quality solutions significantly faster than the state of the art.
A hierarchy of the functional organization for color, form and disparity in primate visual area V2.

Abstract By combining optical imaging, single unit electrophysiology and cytochrome oxidase (CO) histology, we sought to reveal in greater detail the functional organization within the CO stripes of visual area V2 of primates. To visualize the disparity selective regions of V2, the imaging of binocular interaction was employed. These imaging maps guided single unit penetrations that then revealed a columnar organization for disparity. Our studies also showed a pattern of intermixing between the color and disparity pathways of V2, including the existence of single cells tuned for both color and disparity. While previous studies have suggested that the CO stripes of V2 constitute the fundamental organizational unit within V2, our results show a further level of organization consisting of functionally distinct subcompartments, 0.7–1.5 mm in diameter, within individual stripes. These subcompartments, which are not clearly revealed by CO histochemistry, lie within each of the thin, pale, and thick CO dense stripes in V2 and are specific for aspects of color, orientation and retinal disparity, respectively. The present results favor an architectural view of V2, not unlike that of V1, as a collection of functionally distinct subcompartments or modules situated within each of the V2 stripes. These modules also support the notion that for each cortical area (e.g. V1, V2, V4), there exists a stereotyped cortical module with a geometry that is characteristic for each area. These modules exist as a middle tier in a hierarchy of functional organization within V2.
Two Distinct Cohesive Layer Models in Composite Delamination Investigation

[Abstract] The performances of two distinct types of the cohesive layer model are studied, with the ultimate goal of establishing a standard modeling methodology in the prediction of delamination growth initiation and progression. The essential difference between the two models is that the first is a model of finite thickness with appropriately prescribed material properties while the other has zero initial thickness. Experimental results of double cantilever specimens and laminates subjected low velocity impact are invoked in the study. It is seen that the latter model follows the experimental results with greater fidelity whereas the former predicts early termination of delamination growth.
Problems in Correlating In Vitro and In Vivo Studies of Drug Metabolism

No single approach for studying drug metabolism provides all the necessary information required for a complete understanding of the factors that govern the time courses of the concentrations of drugs and other foreign compounds and their metabolites in tissues of the body. Some of the factors are best studied with pure enzymes, while others are best studied with subcellular organelles, intact cells, intact organs or living animals. Well integrated programs encompassing all of these approaches are required if we are ever going to understand fully the metabolism of drugs by living animals and the ways by which pharmacokinetic characteristics may be altered. In order to make extrapolations between approaches, however, it is necessary to test data obtained by various approaches for consistency. Only in this way can we gain confidence that the conclusions derived fromin vitro experiments do indeed account for the events that occurin vivo.
On the cosmic ray cross-field diffusion for solar wind turbulence

The cross-field diffusion coefficient of charged particles in the presence of pure isotropic Alfven waves, pure isotropic magnetosonic waves and their mixture is considered using Monte Carlo particle simulations. We show that the cross-field diffusion coefficient $\kappa_{\perp}$ strongly depends on the assumed spectrum and amplitude of MHD turbulence but much less on the type of waves considered. It is demonstrated that transport perpendicular to the average magnetic field is mostly determined by compound diffusion which combines the effects of scattering off magnetic irregularities with magnetic braiding. The ratio $\kappa_{\perp}/\kappa_{\parallel}D_{\rm M}\approx {\rm const.}$ is independent of rigidity over the wide range considered.
Measurement of thermal lensing in Cr/sup 3+/-doped colquiriites

The first direct measurements of thermally induced lensing in end-pumped Cr/sup 3+/-doped LiSrAlF/sub 6/, LiSrGaAlF/sub 6/, LiSrCaAlF/sub 6/, and LiCaAlF/sub 6/ are reported. Using a sensitive measurement technique, focal lengths as long as 40 m were measured. A thermal model has been created to determine the temperature rise as a function of position inside the laser crystal. This new model calculates the temperature distribution by considering quantum defect, upconversion, and upper state lifetime quenching as heating sources. Thermal lensing in the colquiriites is significantly reduced because of compensation of the temperature-dependent refractive index by the induced photoelastic stress inside the colquiriite crystal.
Devolution and the Social Welfare of Elderly Immigrants: Who Will Bear the Burden?

Growing ethnic diversity translates into rising numbers of individuals facing socioeconomic disadvantage, creating a context in which detailed examinations of public policy are critical for understanding the health care needs of immigrant populations in the United States. Although many scholars document the link between social disadvantage and increased morbidity and mortality, additional analyses are needed to identify specific public policies associated with decreased access to social goods and public services. The implications of the latest welfare bill, the Personal Responsibility and Work Reconciliation Act of 1996, on the health and social welfare of the aging Hispanic population provides a unique opportunity for such inquiry. On the basis of demographic trends and recent analyses of data from the Hispanic Established Populations for Epidemiologic Study of the Elderly, the results suggest that older, Mexican–origin immigrants are likely to become an even greater administrative responsibility of state and local governments.
Concentrations of Ions at the Surfaces of Clays

Equations based on the theory of the structure of the electrical double layer developed at a charged plane surface are used to calculate the concentrations of ions at the surfaces of clays suspended in various electrolyte solutions. The results indicate that in clays where the surface density of charge is high the conditions close to the surface are independent of the outer electrolyte concentration provided that this is not too high. The treatment is applied to the problem of the conditions present at the surfaces of clays suspended in dilute acid, and the effect of the addition of neutral salts on the acidity at the surface is discussed.
What is wrong with appendage theory of consciousness

Abstract The present article distinguishes three kinds of accounts of direct (reflective) awareness (i.e. awareness of one's mental occurrences causally unmediated by any other mental occurrence): mental‐eye theory, self‐intimational theory and appendage theory. These aim to explain the same phenomenon, though each proposes that direct (reflective) awareness occurs in a fundamentally different way. Also, I address a crucial problem that appendage theory must solve: how does a direct (reflective) awareness succeed in being awareness specifically of the particular mental‐occurrence instance that is its object? Appendage theory is singled out for this attention because psychologists, as they embark on their renewed study of consciousness, are most likely to be attracted by appendage theory for their explanation of direct (reflective) awareness.
MOLECULAR GENETIC ANALYSES OF MICROSPOROGENESIS AND MICROGAMETOGENESIS IN FLOWERING PLANTS

In flowering plants, male reproductive development requires the formation of the stamen, including the differentiation of anther tissues. Within the anther, male meiosis produces microspores, which further develop into pollen grains, relying on both sporophytic and gametophytic gene functions. The mature pollen is released when the anther dehisces, allowing pollination to occur. Molecular studies have identified a large number of genes that are expressed during stamen and pollen development. Genetic analyses have demonstrated the function of some of these genes in specifying stamen identity, regulating anther cell division and differentiation, controlling male meiosis, supporting pollen development, and promoting anther dehiscence. These genes encode a variety of proteins, including transcriptional regulators, signal transduction proteins, regulators of protein degradation, and enzymes for the biosynthesis of hormones. Although much has been learned in recent decades, much more awaits to be discovered and understood; the future of the study of plant male reproduction remains bright and exciting with the ever-growing tool kits and rapidly expanding information and resources for gene function studies.
EEG and pathologic findings in patients undergoing brain biopsy for suspected encephalitis.

Abstract Previous studies have suggested that EEG may be helpful in the diagnosis of herpes encephalitis (HE). To further define the value of EEG in an acutely ill, febrile, encephalopathic patient suspected as having encephalitis, we reviewed initial preoperative EEGs with the results of cerebral biopsies in 24 consecutive patients suspected of having encephalitis. Statistical analysis demonstrated that EEG patterns have only limited association with biopsy results. Since diseases which mimic encephalitis may also generate identical EEG changes, this is not an unexpected finding. EEG is useful in the evaluation and management of patients with encephalitis. However, the absence of specific wave forms or focal EEG abnormalities in the proper clinical setting should not deter consideration of HE or delay treatment.
Gas Chromatographic Determination of Hexamethylene Bisacetamide in Plasma and Urine

Abstract A rapid, simple and specific gas chromatographic method has been developed to measure the differentiating agent hexamethylene bisacetamide (HMBA) in biological samples. Addition of a homolog as an internal standard, ultrafiltration and then direct packed column GC-FID analysis of the ultrafiltrate gives a detection limit of less than 50 μg/ml (0.25 mM) for HMBA in plasma or urine. Ultrafiltration is quantitative and assay precision is better than 4.3% for the 1–5 mM range. This method has been applied to determine the bolus dose pharmacokinetics and disposition of HMBA in a single small animal such as a rat. The developed assay should be suitable for therapeutic monitoring of human patients undergoing HMBA treatment.
GPS-Based Satellite Tracking System for Precise Positioning

NASA is developing a Global Positioning System (GPS) based measurement system to provide precise determination of Earth satellite orbits, geodetic baselines, ionospheric electron content, and clock offsets between worldwide tracking sites. The system will employ variations on the differential GPS observing technique and will use a network of nine fixed ground terminals. Satellite applications will require either a GPS flight receiver or an on-board GPS beacon. Operation of the system for all but satellite tracking will begin by 1988. The first major satellite application will be a demonstration of decimeter accuracy in determining the altitude of TOPEX in the early 1990's. By then the system is expected to yield long-baseline accuracies of a few centimeters and instantaneous time synchronization to 1 ns.
Escherichia coli O157:H7 Infections: Discordance between Filterable Fecal Shiga Toxin and Disease Outcome

Shiga toxin (Stx)-producing Escherichia coli O157:H7 are the most common cause of hemolytic uremic syndrome (HUS). We detected free fecal Stx in 48%, 40%, and 17% of infected children with uncomplicated diarrhea, children who subsequently developed HUS, and children with HUS, respectively. Vero cell assay detected Stx more frequently than did a commercial Stx enzyme immunoassay. In children's stool samples obtained on or before day 4 of illness, each 10-fold decrease in titer was, paradoxically, associated with 3.8-fold increased odds of developing HUS (P = .03; 95% confidence interval, 0.77-19.7). The fecal Stx type did not correlate with the Stx expressed by bacteria grown in vitro and was not related to bacterial titer in the studied samples. These data suggest that therapeutic and diagnostic strategies directed toward binding or identifying intraintestinal fecal Stx may have limited success.
The synthesis of organic polymers containing hypervalent Iodine

Polyesters of the formula have been made from iodosobenzenes + acid anhydrides and from iodobenzene diacetates + dicarboxylic acids. The products do not resemble in solubility behavior the iodosobenzene esters of monocarboxylic acids, the polyesters of convential diols, or the ionic salts of dicarboxylic acids. Under the best conditions they are more stable thermally than iodobenzene diacetate or dipropionate, but none is stable above 200°C. There are indications that polymers containing hypervalent atoms represent a new class of polymers by virtue of their unusual solubility behavior and physical properties.
Focal radiation, a method for inducing structural modifications in the immature rat brain†

A new and relatively simple technique for conducting developmental neurology experiments is described. This technique consists of subjecting rats less than four days in age to a collimated source of external beta radiation that can be directed to selected parts of the brain. Use of this method yields the following advantages: (1) the size relationships of the parts of the brain can be altered, (2) bilateral asymmetry of the cerebrum, and/or cerebellum can be produced, (3) chronic functional defects which develop as the rat develops can be obtained, (4) the experimenter may selectively destroy any site in the brain provided that it is superficial enough, and (5) foci of epilation appear on the scalp and serve as markers. The limitations of this method are also discussed.
On Drawing Attention to Ignorance

In the years since a symposium on science and ignorance at the 1993 annual meeting of the American Association for the Advancement of Science (AAAS), a small but growing number of scholars has begun to study scientific ignorance. This essay offers informal descriptions of three major projects on the social construction of ignorance and raises the possibility for the development of a sociology of scientific ignorance (SSI) to complement the existing sociology of scientific knowledge (SSK). As currently conceptualized, SSI would draw attention to a wide range of phenomena in scientific discourse and practice; these include a rich assortment of ignorance claims, and ignorance arrangements, social arrangements that work to deprive people of scientific knowledge. For SSI to develop its full potential will require scholars to overcome ignorance of existing scholarship and resistance within both science and science studies to ignorance as an organizing idea. The benefits, if scholars can do these things, may be ...
Improving the safety of homeless young people with mobile phones: values, form and function

By their pervasiveness and by being worn on our bodies, mobile phones seem to have become intrinsic to safety. To examine this proposition, 43 participants, from four stakeholder groups (homeless young people, service providers, police officers, and community members), were asked to consider how homeless young people could use mobile phones to keep safe. Participants were asked to express their knowledge for place-based safety and to envision how mobile phones might be used to improve safety. Detailed analysis of the resulting data, which included value sketches, written value scenarios, and semi-structured discussion, led to specific design opportunities, related to values (e.g., supporting trust and desire to help others), function (e.g., documenting harms for future purposes), and form (e.g., leveraging social expectations for how mobile phones can be used to influence behavior). Together, these findings bound a design space for how mobile phones can be used to manage unsafe situations.
The Sorokin-Merton Correspondence on “Puritanism, Pietism and Science,” 1933–34

On this occasion, I shall try to respond to the suggestions that I report what it was like to be a graduate student at Harvard in the early 1930s engaged in writing a dissertation which took the shape in print of the monograph, Science, Technology and Society in Seventeenth-Century England. This, quite some time before the sociology of science had emerged with a cognitive and social identity. I shall not attempt an account – let alone an explanatory account – of the micro-environment at Harvard back then that provided local context for that study. Indeed, I suspect that the Gerald Holton, Everett Mendelsohn and Arnold Thackray reconstructions come closer to the intellectual and social reality of that time and place than anything I might reconstruct.
Recovering from Inconsistency in Distributed Simple Temporal Networks.

Simple Temporal Networks (STNs) are frequently used in scheduling applications, as they provide a powerful and general tool for managing temporal constraints. One obstacle to their use in multi-agent scheduling contexts, however, is the additional problem of maintaining consistency across agent models. Like in centralized applications, unexpected execution results (e.g., an activity taking longer to execute than planned) can introduce conflicts into an agent’s local model that require changes to its current local schedule. But in a distributed environment these local changes must also be propagated to those other agents with interdependent decisions, and the asynchrony and latency of this communication can introduce inter-agent inconsistency. In this paper, we consider the problem of managing and recovering from detected inconsistencies in a distributed STN-based scheduling framework. Our approach exploits a higher, domain-level semantics of the temporal constraints posted in the STN to design a set of strategies to update the agent’s schedule and resolve the STN conflict. We present experimental results on a suite of problems involving coordinated management of joint schedules that indicate the potential of our approach.
Utilizing the retiming-skew equivalence in a practical algorithm for retiming large circuits

The introduction of clock skew at an edge-triggered flip-flop has an effect that is similar to the movement of the flip-flop across combinational logic module boundaries, and these are continuous and discrete optimizations with the same effect. While this fact has been recognized before, this paper, for the first time, utilizes this information to find an optimal retiming. The clock period is guaranteed to be at most one gate delay larger than the optimal clock period found using skew alone; note that since skew is a continuous optimization, it is possible that the optimal period may not be achievable. The method views the circuit hierarchically, first solving the clock skew problem at one level above the gate level, and then using local transformations at the gate level to perform retiming for the optimal clock period. The solution is thus divided into two phases. In Phase A, the clock skew optimization problem is solved with the objective of minimizing the clock period, while ensuring that the difference between the maximum and the minimum skew is minimized. Next, in Phase B, retiming is employed and some flip-flops are relocated across gates in an attempt to set the values of all skews to be as close to zero as possible.
A multivariate frequency-domain approach to long-lead climatic forecasting

Guided by the increasing awareness and detectability of spatiotemporally organized climatic variability at interannual and longer timescales, the authors motivate the paradigm of a climate system that exhibits excitations of quasi-oscillatory eigenmodes with characteristic timescales and large-scale spatial patterns of coherence. It is assumed that any such modes are superposed on a spatially and temporally autocorrelated stochastic noise background. Under such a paradigm, a previously described (Mann and Park) multivariate frequency-domain approach is promoted as a particularly effective means of spatiotemporal signal identification and reconstruction, and an associated forecasting methodology is introduced. This combined signal detection/forecasting scheme exhibits significantly greater skill than conventional forecasting approaches in the context of a synthetic example consistent with the adopted paradigm. The example application demonstrates statistically significant skill at 5‐ 10-yr lead times. Applications to operational long-range climatic forecasting are motivated and discussed.
Mouse Models of Gastric Cancer

Animal models have greatly enriched our understanding of the molecular mechanisms of numerous types of cancers. Gastric cancer is one of the most common cancers worldwide, with a poor prognosis and high incidence of drug-resistance. However, most inbred strains of mice have proven resistant to gastric carcinogenesis. To establish useful models which mimic human gastric cancer phenotypes, investigators have utilized animals infected with Helicobacter species and treated with carcinogens. In addition, by exploiting genetic engineering, a variety of transgenic and knockout mouse models of gastric cancer have emerged, such as INS-GAS mice and TFF1 knockout mice. Investigators have used the combination of carcinogens and gene alteration to accelerate gastric cancer development, but rarely do mouse models show an aggressive and metastatic gastric cancer phenotype that could be relevant to preclinical studies, which may require more specific targeting of gastric progenitor cells. Here, we review current gastric carcinogenesis mouse models and provide our future perspectives on this field.
A 10 bit 75 mega-sample per second A/D converter

Metastability and limitations in sample frequency in subranging A/D (analog-to-digital) converter topologies are explored. A monolithic 10-b A/D converter utilizing multiple subranging digitizers to eliminate metastable states and increase sample speed is presented. This converter uses an extension of the dual rank architecture to eliminate the potential for metastable states associated with the coarse rank thresholds. Highly linear input amplifiers are utilized to drive the residue signal, simplifying the input drive requirements. The residue amplifier incorporates clamping circuitry to minimize the effect of overdrive signals on settling time and accuracy. >
A Numerical Study of Energy Separation in a Jet Flow

Redistribution of the total energy of a fluid in motion, which is called "energy separation," has been observed in various flow situations. Understanding the underlying mechanism of this interesting phenomenon has been limited due to lack of the temporal information on flow and temperature fields. In the present study, numerical simulation of a viscous circular jet was performed to provide detailed temporal information on pressure, vorticity, and total temperature fields. Nondimensionalized governing equations, including mass, momentum, and total energy conservation equations, were simultaneously solved by an equal-order linear finite element and fractional four-step method. The results show that the formation and transport of vortices induce a pressure fluctuation in the flow field. The fluid, which flows through the disturbed pressure field, exchanges pressure work with the surroundings, and gains or loses total energy. This work exchange leads to higher and lower total temperature regions than the surroundings. In addition to the presence and movement of the vortices, the results indicate that the vortex-pairing process significantly intensifies the pressure fluctuation and corresponding total temperature difference. This implies that the vortex-pairing process is a very important process in intensifying energy separation and might explain the enhancement of energy separation in a jet using acoustic excitation.
An Incoherent Optical Correlator for Real-time Pattern Recognition

A new incoherent optical image correlator is presented which does not require a hologram to store the reference image information. Theoretical analysis is given to describe the system operation. Experimental results have confirmed that this correlator is capable of performing real-time pattern recognition. A one-dimensional edge-enhancement technique can be used to sharpen the correlation peak. Scale-invariant operation has been realized by adopting an adaptive frequency modulated acousto-optic device.