cssi/SciSciGPT-SciSciNet huggingface dataset:
Resolution dependent errors in remote sensing of cultivated areas

Remote sensing has become a common and effective method for estimating the areal coverage of land cover classes. One class of particular interest is agriculture as area estimates of cultivated lands are important for purposes such as estimating yields or irrigation needs. The synoptic coverage of satellite imagery and the relative ease of automated analysis have led to widespread mapping of agriculture using remote sensing. The accuracy of area estimates derived from these maps is known to be related to the accuracy of the maps. However, even in the situation where the map is very accurate, errors in area estimates may occur. These errors result from the behavior of the distribution of subpixel proportions of cultivated areas, and how that behavior changes as a result of sensor spatial resolution and class definitions. The sensitivity of estimates of cultivated areas to sensor spatial resolution and to the choice of threshold used to define cultivated land is explored in six agriculturally distinct locations around the world. Using a beta model for the distribution of subpixel proportions that is parameterized using variograms, it is possible to model the distribution of subpixel proportions for any spatial resolution. When the spatial resolution is small with respect to the spatial structure of the landscape (as measured by the variogram range) use of any class definition threshold produces an estimate very close to the true area coverage. On the other hand, as the resolution becomes coarse in relation to the variogram range, the subpixel proportions are no longer concentrated at the extremes of the distribution and the difference between the estimated and the true area has greater sensitivity to the selected threshold used to define classes. Thus, for the cases examined here, both the resolution and the class definition threshold have a strong influence on area estimates. The spatial resolutions where errors can be large depend on landscape spatial structure, which can be quantified using variograms. The net effect is that for the same spatial resolution, some places will exhibit much larger errors in area estimates than others. For the site in the Anhui province of China, where agricultural fields are very small (0.07 ha on the average), area estimates are highly sensitive to class definition thresholds even at the relatively fine resolution of 45 m. Conversely, in California (USA) spatial resolutions as coarse as 500 m can be used to reliably estimate cultivated areas. Results also suggest that the proportion of the total area that is cultivated significantly influences the accuracy of area estimates. When the area proportion is low, the class definition threshold must also be low to achieve an accurate area estimate. Conversely, in areas dominated by agriculture, a very stringent class definition of cultivated lands is required for accurate area estimates. While explored in the context of estimation of cultivated areas, the findings presented here are generic to the problem of area estimation using remote sensing.
Meissner response of anisotropic superconductors

The response field of a half-space anisotropic superconductor is evaluated for an arbitrary weak external field source. Example sources of a point magnetic moment and a circular current are considered in detail. For the penetration depth $\ensuremath{\lambda}\ensuremath{\ll}L$ with L being any other relevant distance (the source size or the distance between the source and superconductor), the major contribution to the response is the \ensuremath{\lambda}-independent field of the source image. It is shown that the absolute value of \ensuremath{\lambda} cannot be extracted from the response field with a better accuracy than that for the source position. Similar problems are considered for thin films.
Congressional hearings: Neglected sources of information on American Indians

Abstract Over the past three decades, discussion of government documents on American Indians has emphasized federal agency documents and archival records. Despite the fact that Congress has the ultimate authority in Indian affairs, document librarians have not explored the considerable research potential of hearings as a format for information. This article will show, with examples from early twentieth century legislative and oversight hearings, that there is significant untapped research content on American Indians in congressional hearings.
Decreased glucose tolerance, not decreased insulin sensitivity, is a maturational abnormality in the male offspring of a parent with early coronary artery disease☆

We investigated whether the male offspring of a parent with early coronary artery disease (before the age of 60; n = 61) exhibit decreased insulin sensitivity compared with controls matched for age and body mass index (BMI) (n = 39). The insulin sensitivity index (SI) was determined by the minimal modeling method of Bergman from a frequently sampled intravenous glucose tolerance test with intravenous tolbutamide. Offspring and controls had a similar SI, insulin-independent glucose utilization (SG), first-phase insulin response (AIRG), and area under the glucose curve. When subjects were separated into two age groups, younger subjects aged 15 to 30 years and older subjects aged 31 to 45 years, important differences were seen. SG was significantly increased in younger offspring compared with controls (22.8 ± 2.3 v 16.8 ± 2.3 × 10−3 · min−1, P < .05). Older offspring had a significantly increased area under the glucose curve compared with controls (18,250 ± 322 v 17,225 ± 347 mg/dL · min−1, P < .05). Older offspring also had decreased SI compared with younger offspring (5.0 ± 0.4 v 6.6 ± 0.9 × 10−4 · min−1, · μ U/mL, P < .05), but this difference was eliminated after adjusting for BMI and waist to hip ratio (5.5 ± 0.4 v 5.8 ± 0.9 × 10−3 · min−1, nonsignificant). This study does not support the concept that insulin resistance is an early atherogenic risk factor in offspring at risk for coronary disease because of their family history. However, it does point to the importance of maturational changes in glucose homeostasis in these offspring.
Site-exposure model for proton-lactose symport in Escherichia coli.

Abstract A model is presented for the lactose-proton co-transporter of E. coli. Either proton translocation inwards or galactoside translocation outwards brings about the exposure of galactoside binding sites externally. This alternation in the exposure of the galactoside binding site to either side of the membrane is viewed as the fundamental event in coupled uptake, rather than affinity changes for galactoside. The transporter is proposed to function as a dimer, exhibiting two forms corresponding to the “cis” and the “trans” orientation of the two galactosyl binding sites. A galactoside or a proton gradient brings about conversion of the sites from the “trans” to the “cis” configuration. The two forms can be experimentally differentiated by the accessibility of non-transportable substrate analogs to the galactosyl binding sites.
Ultrafast manipulation of electron spin coherence in quantum wells

A recently developed technique is reviewed with the potential for all-optical coherent control over electron spins in semiconductors. In these experiments, ultrafast laser pulses "tip" electron spins by generating effective magnetic fields via the optical Stark effect. Measurements of Stark shifts have provided estimates of the net tipping angle as a function of tipping pulse energy, intensity, and polarization. Background contributions to the measured tipping angle arise from the undesirable excitation of additional carriers by the tipping pulse.
New formulations of a Stokes type problem related to the primitive equations of the atmosphere and applications

The aim of this article is to propose new algorithms for a Stokes type system related to the primitive equations of atmosphere, which are the fundamental equations for the motion of the atmosphere [6]. We derive an equivalent formulation of these equations in which the natural constraint appearing in these equations is automatically satisfied without being explicitly imposed. Numerical algorithms based on the new formulation appeared to be very competitive compared to the Uzawa-Conjugate Gradient method.
Access conflicts in multiprocessor memories queueing models and simulation studies

The performance of an interleaved common memory accessed uniformly by multiple processors is modeled by queueing methods. The model includes access conflicts at the bank level while assuming an ideal access network.A scaling relation is derived that is generally valid and indicates that memory access delays are given by the product of the bank reservation time and a function of the memory utilization, which is given by the average number of access requests arriving at a bank per bank reservation time. For light memory traffic, access delays are proportional to the square of the bank reservation time and the ratio of the number of active memory access streams to the number of memory banks.Assuming random access patterns, an open and a closed queueing model are developed that are validated by simulations. Delay dependence on bank reservation time is quadratic for light loads and linear for very heavy loads.A heuristic extension of our model for vector accessing of banks in sequential mode is proposed.
Center-Based Early Head Start and Children Exposed to Family Conflict

Research Findings: Family conflict is known to be associated with poor development for young children, but many children appear resilient. This study examined the extent to which high-quality center care during early childhood protects children from these negative consequences. Children participating in center-based sites of the Early Head Start (EHS) Research and Evaluation study were grouped based on their treatment status: 305 children receiving EHS services, and 305 children not receiving EHS services. Family conflict was positively associated with aggressive behavior as reported by parents for children at 3 and 5 years of age for comparison children but not for children in EHS center-based programs. However, moderation impacts were not observed for objective ratings of child negativity to parent in semistructured interactions. Practice or Policy: These findings may suggest that attending lesser quality child care and living in a family characterized by conflict is associated with heightened aggressiv...
Synthesis and characterization of jar-like ZnO structures

A new jar-like ZnO structure was synthesized by heating a mixture of Zn and InI3 powder with a weight ratio of 4:1 dispersed on Si wafer at 450°C in air. The diameter of the jar was of the order of 15 μm and the length of 20 μm. The formation of a molten InI3 drop, coating the drop with Zn powders, oxidation of these Zn grains, decomposition of InI3 to In and I vapors and the subsequent release of these vapors from the structure are considered important steps in the formation of the observed structures. The necessary elements in forming such structures are analyzed, which can be used as a guide in the design of experiments to synthesize similar structures for different purposes. Such structures are predicted to be able to soak large amount of liquid and release it at low rate, which is a desired property in some applications.
Multi-domain binding of cytochrome c peroxidase by cytochrome c: Thermodynamic vs. microscopic binding constants

We have demonstrated that cytochrome c (Cc) binds to cytochrome c peroxidase (Cc P) with a 2:1 stoichiometry, and that: (i) Cc reacts at two distinct and non-exclusive surface domains of Cc P; (ii) two molecules of Cc can bind simultaneously to Cc P; and (iii) the ternary complex is more reactive than the binary complex for the heme—heme reaction. The quenching studies, however, provide only stoichiometric (thermodynamic) parameters. They do not directly probe the microscopic properties of the individual domains, and thus do not apportion the reactivity due to 1:1 stoichiometry between the two types of binary complexes: one with Cc bound at the high-affinity domain and one with Cc bound at a low-affinity domain. We describe here a method for analyzing the stoichiometric parameters obtained from triplet quenching titrations to partition the quenching of ZnCc by Cc P into contributions from the binary and ternary complexes, and also to give limits on the partition of the quenching into contributions from the low- and high-affinity binding domains. By applying this method to the experimental quenching titration data for the multi-domain binding of Cc to Cc P, we were able to evaluate, for the first time, the functional relevance of the low-affinity domain in the binary and ternary complexes at both low and high ionic strength. At low ionic strength, essentially no Cc binds at the low-affinity domain in a binary complex. However, reactivity at this domain is significant and indeed can be dominant, in the ternary complex, which does form with measureable concentration. At higher, more physiologically-relevant ionic strengths, very little ternary complex forms, but now the situation is changed, and there is significant reactivity from the 1:1 complex with Cc bound at the low-affinity domain. In other words, there is substantial reactivity from Cc bound at the weakly binding domain over a wide range of ionic strengths, either in a binary or a ternary complex. Finally, we suggest that at high ionic strength, interactions between the two bound Cc are shielded such that it is easier to bind the second Cc molecule when one domain is occupied already.
Near affine Hjelmslev planes

Abstract A study is made of two generalizations of affine Hjelmslev planes in which the parallel axiom is not required to hold. Integer invariants are obtained for the finite planes in these new classes. Formulas are derived which enable one to compute the cardinalities of certain subsets of points and lines in terms of the invariants, and results are obtained on the nonexistence of planes with certain sets of invariants.
Quantum gravity in two dimensions: Exact solution of the Jackiw model.

The two-dimensional theory of gravity proposed by Jackiw is exactly quantized in the open case. The Wheeler-DeWitt equation is solved in closed form with and without cosmological constant. The theory has no degree of freedom and the unique wave functional reflects the classical aspects of the solution.
Status Deprivation and Delinquent Behavior

THE relationship between delinquent behavior and life style in the slums of London and Paris reported over a hundred years ago finds its counterpart in contemporary metropolitan America.' Evidence for the population of the present study shows that official delinquency rates vary inversely with socioeconomic status.2 There are some who argue that differential enforcement of the law and handling of law violators from the socioeconomic levels of the population accounts for these observed differences in official rates of delinquency., But assuming the relationship between delinquent behavior and socioeconomic status to be valid, the question quite naturally arises, what is there about low socioeconomic status that generates high delinquency rates? One explanation for this relationship is Albert K. Cohen's theory of subcultural delinquency. A too brief statement of his theory is that working-class boys, to the degree that they value middle-class status, experience status frustration when in status competition. Status frustration generates a problem of adjustment and places these boys in the market for a solution. Delinquency is often a collective subcultural solution to this status frustration because it provides criteria of status which these adolescents can meet.4 Cohen's theory necessarily postulates that adolescents have developed a conscious awareness or perception of differences in class
Subcellular location of S-adenosylmethionine:Δ24 sterol methyltransferase in Saccharomyces cerevisiae

Abstract Adaptation of anaerobically grown yeast cultures to oxidative conditions produces a rapid burst of ergosterol synthesis with concomitant formation of mitochondria. Mitochondrial enzymes are derepressed and synthesized de novo either on cytoplasmic or mitochondrial ribosomes during adaptation, and are subsequently incorporated into developing and mitochondrial structures. The dependence of mitochondrial formation and respiratory competence on the presence of ergosterol has indicated a close relationship between the development of the two systems. Properties of S -adenosylmethionine: Δ 24 sterol methyltransferase (EC 2.1.1.41), an enzyme involved in the terminal stages of ergosterol biosynthesis, have been examined in yeast during aerobic adaptation. The subcellular location of this enzyme is the promitochondria or mitochondria. The enzyme is synthesized on cytoplasmic ribosomes and coded for in nuclear DNA. The enzyme is present at low levels during anaerobic growth and is not subject to repression by high levels of glucose.
Factors Contributing to Achievement in the Study of Elementary German

THIS paper is a report on an experimental investigation2 of the study habits used by Liberal Arts and Sciences freshmen at the University of Illinois in their study of elementary German. The investigation is concerned with factors which may be responsible, in part, for differences in student achievement when intelligence scores are held constant. The factors believed to have a bearing upon success in learning German were divided into those measurable by achievement or ability tests and those to be studied by interview and questionnaire methods. In order to rule out the factor of intelligence we selected two groups of students with equal measured mental ability and with widely discrepant achievement in German. As a criterion of achievement the unweighted scores on the Cooperative German Test, Elementary Form O, were used. The Otis Quick-Scoring Mental Ability Test, Gamma Test: Form B, was used to measure mental ability. These tests were administered during the first week of the second semester, 1939-40, to all Liberal Arts and Sciences freshmen enrolled in their second semester of German.
Structural analysis of an NDE-inspected carbon-carbon component

In this research, it is demonstrated that the integration of nondestructive evaluation with the finite element method (a quantitative NDE/FEM approach) can be used for analysis and behavior prediction of advanced materials, such as fiber composites, after processing and during in-service testing. First, stress, strain, and energy data were calculated by the finite element method for square plates with a 10 percent difference in the material properties between specified segments, i.e., between the center and the outside section or between two halves of the plate. This demonstrated the efficiency of the method in predicting variations in the structural behavior based on small material property differences. Then, finite element analyses and actual axial compression tests were performed on a Space Shuttle brake stator made from woven carbon-carbon composites. The material properties used in the numerical modeling of the stator were previously characterized at a large number of points on the component by quantitative NDE-procedures, i.e., ultrasonics and radiography. The results from the experimental compressive loading tests were used to verify the NDE/FEM results. Good agreement was found for most parameters.
A two-dimensional, diagonal sodium dodecyl sulfate-polyacrylamide gel electrophoresis technique to screen for protease substrates in protein mixtures

Proteases have emerged during the past few years as key players in the control of cell fate. Many have been identified and cloned, but to understand their function and to elucidate the pathways in which they are involved, the intracellular substrates processed by each protease must be identified. Even the intensive efforts in genome sequencing and cloning that yield new protein sequences every day do not provide a complete solution: the occurrence of a cleavage motif in a protein sequence is not sufficient for proteolytic susceptibility since folding may prevent access of the protease to the substrate site.
Optimal Glideslope Guidance for Spacecraft Rendezvous

M ANY space applications involve rendezvous with a vehicle in circular orbit. A subset of these applications requires the visiting vehicle to approach with a constant direction as seen by the target. This is the case for vehicles approaching the International Space Station (ISS), for example. By approaching it in a straight line the crew onboard the station can easily monitor nonnominal situations. The space shuttle employs a straight-line guidance law called glideslope [1]. Vehicles visiting the ISS usually employ a fixed-direction terminal approach, including H-II Transfer Vehicle (HTV) [2], Automated Transfer Vehicle (ATV) [3], and Cygnus [4]. In this work a constant direction guidance law is developed to rendezvous a target in circular orbit. This type of trajectory is referred to as glideslope. Much work exist in the general area of optimal space trajectories, an illustrative early work is that by Lawden [5]. Carter [6] studied minimum delta-v maneuvers to rendezvous with a vehicle in circular orbit. The approach used by Carter and by many authors after him is to optimize the system subject to the linearized dynamics, the socalled Clohessy–Wiltshire equations [7]. The rendezvous strategy by Lembeck and Prussing [8] is to add to an initial impulsive phase a low-thrust phase. Since continuous thrust is necessary to guide on the glideslope, this work also assumes low-thrust propulsion. Various aspects of this problemwere generalized. Carter andHumi [9] study the impulsive rendezvous in proximity of a general Keplerian orbit, while Carter [10] studies the continuous-thrust case. Power limitations and thrust bounds are also studied [11]. Guelman and Aleshin [12] develop a two-stage solution for the fixed-direction terminal approach. The first stage consists of an unconstrained optimization that puts the vehicle on the glideslope. The second stage is along the glideslope. In this work only the terminal phase is considered, when the spacecraft is required to fly on the glideslope. The current work differs considerably from the work of Guelman andAleshin [12]. In their work the constraint is not enforced directly, but the squared distance to the glideslope is added to the performance index with a weighting parameter. The bigger the parameter the closer the constraint is to be satisfied. This work’s approach is to satisfy the constraint exactly. Another difference between the two works is that Guelman and Aleshin solve their optimization numerically, while a closed-form solution is presented in this Note. The optimal guidance solution applies when the vehicle is on the glideslope. In practice, an inner-loop controller is needed tomaintain the vehicle on the desired terminal direction. II. Optimal Guidance
Use of pilocarpine during head and neck radiation therapy to reduce xerostomia and salivary dysfunction

Background. Salivary gland hypofunction commonly develops during radiation therapy to the head and neck region. This study evaluated whether the sialogogue pilocarpine given during radiation therapy may reduce the severity of xerostomia and salivary dysfunction. Methods. Nine patients requiring head, neck, or mantle radiation therapy participated in this double-blind, placebo-controlled trial. The patients took either 5 mg of pilocarpine or placebo four times daily for 3 months, beginning the day before radiation therapy. Subjective complaints and salivary functions were assessed. Results. The pilocarpine-treated group had a lower frequency of oral symptoms during treatment than the placebo-treated group. Although salivary flow decreased in all patients, the pilocarpine-treated group had smaller reductions in flow. No drug effect was observed in glands that were irradiated completely. Thus, pilocarpine appeared to stimulate salivary tissues outside the radiation field. Conclusions. These results suggest that stimulation with pilocarpine may reduce the severity of salivary dysfunction and associated oral symptoms during radiation therapy.
Ultrahigh-speed photonic analog-to-digital conversion technologies

This paper summarizes our recent work on high-speed photonic analog-to-digital conversion (A/D) technologies, where picosecond pulses generated by a 10 GHz mode-locked laser source were used to accomplish low-jitter photonic sampling. In addition, we describe our progress in the generation of 40 GHz wavelength-coded pulses for time-interleaved A/D, and the demonstration of photonic bandpass (at 1.6 GHz) Δ-∑ quantizers clocked at 10 GHz.
Properties of esterases from pharate pupal moulting fluid of the tobacco hornworm, Manduca sexta

1. 1. Three esterolytic fractions (I–III) were partially purified by chromatographic procedures from pharate pupal moulting fluid of the tobacco hornworm, Manduca sexta L. 2. 2. Maximum activity toward 1-naphthyl acetate occurred at pH ≥ 8 for I and between pH 6 and 7 for II and III. 3. 3. The apparent Michaelis constants for 1-naphthyl acetate were 145, ≥500 and 46 μM for I, II and III, respectively. 4. 4. I and III were inhibited by diisopropylphosphorofluoridate. II was inactivated by p-chloromercuribenzoate. 5. 5. I also hydrolyzed acetylthiocholine and this activity was inhibited by eserine. 6. 6. While all of the fractions hydrolyzed juvenile hormone, III was greater than 10 times more active than the other enzymes. 7. 7. These results suggest that I is a mixture of carboxylesterases and cholinesterases, that II is an arylesterase, and that III contains carboxylesterase and JH esterase enzymes.
A petroleum discovery-rate forecast revisited—The problem of field growth

A forecast of the future rates of discovery of crude oil and natural gas for the 123,027-km2 Miocene/Pliocene trend in the Gulf of Mexico was made in 1980. This forecast was evaluated in 1988 by comparing two sets of data: (1) the actual versus the forecasted number of fields discovered, and (2) the actual versus the forecasted volumes of crude oil and natural gas discovered with the drilling of 1,820 wildcat wells along the trend between January 1, 1977, and December 31, 1985. The forecast specified that this level of drilling would result in the discovery of 217 fields containing 1.78 billion barrels of oil equivalent; however, 238 fields containing 3.57 billion barrels of oil equivalent were actually discovered. This underestimation is attributed to biases introduced by field growth and, to a lesser degree, the artificially low, pre-1970's price of natural gas that prevented many smaller gas fields from being brought into production at the time of their discovery; most of these fields contained less than 50 billion cubic feet of producible natural gas.
Using RNAi to catch Drosophila genes in a web of interactions: insights into cancer research

The completion of whole-genome sequencing of various model organisms and the recent explosion of new technologies in the field of Functional Genomics and Proteomics is poised to revolutionize the way scientists identify and characterize gene function. One of the most significant advances in recent years has been the application of RNA interference (RNAi) as a means of assaying gene function. In the post-genomic era, advances in the field of cancer biology will rely upon the rapid identification and characterization of genes that regulate cell growth, proliferation, and apoptosis. Significant efforts are being directed towards cancer therapy and devising efficient means of selectively delivering drugs to cancerous cells. In this review, we discuss the promise of integrating genome-wide RNAi screens with proteomic approaches and small-molecule chemical genetic screens, towards improving our ability to understand and treat cancer.
Bypassing the requirement for MYC in lymphoma progression

Recent studies in mice engineered to express regulatable alleles of MYC, RAS, and other oncogenes support the general principle that the genetic lesions that initiate tumorigenesis are often essential to maintain the malignant phenotype. The general design of many of these experiments may be
Insulin‐like growth factor‐I improves cellular and molecular aspects of healing in a collagenase‐induced model of flexor tendinitis

Flexor tendinitis is a common and debilitating injury of elite and recreational athletes. Healing may be improved through intratendinous injection of insulin-like growth factor-I (IGF-I), which has been shown in vitro to stimulate mitogenesis and enhance tendon matrix production. This study investigated the effects of intratendinous injection of IGF-I on tendon healing in an equine model of flexor tendinitis. Collagenase-induced lesions were created in the tensile region of the flexor digitorum superficialis tendon of both forelimbs of eight horses. Treated tendons were injected with 2 μg rhIGF-I intralesionally every other day for 10 injections, while controls received 0.9% NaCl. Tendon fiber deposition and organization were evaluated serially using ultrasonography throughout the 8 week trial period. Following euthanasia, the tendons were harvested and DNA, hydroxyproline, and glycosaminoglycan content determined, mechanical strength and stiffness evaluated, gene expression and spatial arrangement of collagen types I and III assessed by northern blot and in situ hybridization, and tendon fiber architecture assessed by polarized light microscopy. Local soft tissue swelling was reduced in the IGF-I treated limbs. Similarly, lesion size in IGF-I treated tendons was smaller 3 and 4 weeks after initiation of treatment. Cell proliferation and collagen content of the IGF-I treated tendons were increased compared to controls. Mechanically, IGF-I treated tendons showed a trend toward increased stiffness compared to saline treated controls. Considered together with the decreased soft tissue swelling and improved sonographic healing, these data support the potential use of intralesional IGF-I for treatment of debilitating tendon injuries.
Fluorescence Quenching Kinetics of Anthracene Covalently Bound to Poly(Methacrylic Acid): Midchain Labeling

Poly(methacrylic acid) labeled by anthracene in the middle of the chain (A-m-PMA) has been synthesized by anionic polymerization of tert-butyl methacrylate followed by introduction of the difunctional terminating agent 9,10-bis(bromomethyl)anthracene. Deprotection to yield the polyacid using trifluoroacetic acid in the presence of thioanisole results in complete removal of the tert-butyl moieties without destruction of the anthracene chromophore. Steady-state and time-resolved fluorescence quenching by Tl+ in aqueous solution at pH 11 at different ionic strengths has been measured. The data have been analyzed and compared to data previously obtained for 9-ethanolanthracene pendant-labeled poly(methacrylic acid) (9EA-PMA) using the following kinetic models: Stern−Volmer; hindered-access; combined Stern−Volmer−Perrin model developed by Morishima et al. (Macromolecules 1993, 26, 4293). These two polymers exhibit very similar quenching behavior, with the most significant difference being that static quenchin...
Modeling laser radar systems in the Night Vision Integrated Performance Model (NV-IPM)

Active imaging systems are currently being developed to increase the target acquisition and identification range performance of electro-optical systems. This paper reports on current efforts to extend the Night Vision Integrated Performance Model (NV-IPM) to include laser radar (LADAR) systems for unresolved targets. Combining this new LADAR modeling capability with existing sensor and environment capabilities already present in NV-IPM will enable modeling and trade studies for military relevant systems.
Collision Avoidance and Improving Space Surveillance

Satellite collision avoidance and other efforts to reduce man-made hazards to operating satellites present numerous opportunities for international cooperation. In fact, this article argues that such cooperation and cooperation of commercial and government satellite operators may be required in order to minimize the number of false alarms, to minimize the possibility that a satellite may perform a maneuver that would increase the risk of collision or other interference, and, as a result, minimize the operational cost of such a service.
N.A.G.: network auralization for Gnutella

N.A.G. (Network Auralization for Gnutella) is interactive software art designed to actively involve a lay public without musical training in a creative musical experience. Users enter search keywords, and the software looks for matching music files on the Gnutella peer-to-peer file-sharing network. As it downloads music, it plays an audio collage whose structure is based on the relative download rates of the files.
Simple Optical Models for Diagnosing Surface-Atmosphere Shortwave Interactions.

Abstract A technique is developed for diagnosing effective surface and atmospheric optical properties from climate model shortwave flux diagnostics. These properties can be used to distinguish the contributions of surface and atmospheric optical property changes to shortwave flux changes at the surface and top of the atmosphere. In addition to the four standard shortwave flux diagnostics (upward, downward, surface, and top of atmosphere), the technique makes use of surface-down and top-up fluxes over a zero-albedo surface obtained from an auxiliary online shortwave calculation. The simple model optical properties, when constructed from the time-mean fluxes, are effective optical properties, useful for predicting the time-mean response to optical property changes. The technique is tested against auxiliary online shortwave calculations at four validation albedos and shown to predict the monthly mean surface absorption with an rms error of less than 2% over the globe. The reasons for the accuracy of the tech...
Antenatal diagnosis of sickle cell anaemia by direct analysis of the sickle mutation

Sickle cell anemia was detected antenatally by restriction analysis with the enzyme Dde I, which cleaves normal human DNA at the position corresponding to aminoacid number 6 of the beta-globin chain. This site is abolished by the mutation in sickle cell disease, and hence different-sized fragments are generated on digestion of normal and sickle genes with this enzyme. In a pregnancy at risk for sickle cell anaemia, digestion of DNA from cultured amniotic fluid cells revealed a pattern indicating the haemoglobin AA genotype. The diagnosis was later confirmed by fetal blood analysis. The test proved applicable to the sickle gene from Africa, Asia, The Middle East, and two Mediterranean countries.
A q-analog of hypergeometric series well-poised in tSU(n) and invariant G-functions

Abstract We introduce natural q-analogs of hypergeometric series well-poised in SU(n), the related hypergeometric series in U(n), and invariant G-functions. We prove that both the SU(n) multiple q-series and the invariant G-functions satisfy general q-difference equations. Both the SU(n) and U(n) q-series are new multivariable generalizations of classical basic hypergeometric series of one variable. We prove an identity which expresses our U(n) multiple q-series as a finite sum of finite products of classical basic hypergeometric series. These U(n) q-series also satisfy an elegant reduction formula which is analogous to the “inclusion lemma” for classical invariant G-functions.
Extracellular pressure stimulates colon cancer cell adhesion in vitro and to surgical wounds by Src (sarcoma protein) activation.

Background: We hypothesized that pressure stimulates colon cancer cell adhesion to surgical wounds. Methods: We quantitated adhesion of murine 26/51 transplantable colon cancer cells by cell counting or chromium 51-labeling. Tumor cells were added to murine surgical wounds after 30 minutes preincubation under ambient or 15 mm Hg increased pressure. Src activation was assayed by immunoblotting for phosphorylated Src and inhibited by 4-amino-5-(4chlorophenyl)-7-(t-butyl)pyrazolo-[3-4-d]pyrimidine (PP2). Results: Pressure stimulated colon 26/51 cell adhesion to murine wounds by 43% to 52% (n = 9, P <0.05 each). Pressure stimulated Src phosphorylation by 39% ± 4% (n = 5, P = 0.004) in colon 26 cells. The Src inhibitor PP2 (20 μmol/L) did not inhibit Src phosphorylation at ambient pressure but prevented pressure stimulation of Src phosphorylation. Src blockade by PP2 did not affect basal adhesion of either tumor to murine wounds but completely blocked pressure stimulation of adhesion (n = 4, P <0.001 each). Conclusions: Increased pressure may activate cancer adhesion to surgical wounds via Src. Src antagonists might inhibit this process.
Laminar ShearStress Pattern for Nonsimilar Incompressible Boundary Layers

A technique has been developed and applied to the solution of the laminar incompressible nonsimilar boundarylayer problem. The basic feature of this method involves the finding of a strained value of the Gortler's Principle Function such that the corresponding zero-order similarity solution provides a highly accurate approximate sheer stress result at the wall. The method can be applied locally without reference to other streamwise locations. Working charts and tables of the required universal function are provided to facilitate computations. Several examples are given to illustrate the present technique and to demonstrate its effectiveness and accuracy.
Pufendorf and Condillac on Law and Language

AbstractThis essay argues that Pufendorf conceived the principles of natural law against the rationalism and innatism of the 17th century, and that Condillac similarly formulated a conception of the human origin of language, both of them thus securing open and human foundations for the two primal institutions of law and language, and also making all citizens free agents in the ordering of communal living.
Glycosaminoglycan synthesis by adult rat submandibular salivary-gland secretory units

Abstract The synthesis of glycosaminoglycans (GAG) by a preparation of purified, functional submandibular-gland secretory units (acini and intercalated ducts) was examined. Such units were isolated from Sprague-Dawley rats by digestion of minced gland with hyaluronidase and collagenase followed by gentle sieving of the digest through a graded series of Teflon screens. They incorporated amino acids into exocrine proteins which could be released by stimulation with isoproterenol as in vivo , indicating their functional integrity. Secretory units, incubated for 2 h in medium containing [ 35 S]-sodium sulphate alone or in combination with [ 3 H]-glucosamine, were then washed, homogenized and digested in pronase. The resulting material was then sequentially digested by specific enzymic and chemical procedures and analysed by chromatography on Sephadex G-50 columns to identify the various GAG synthesized. Secretory units synthesized a GAG mixture which was 20–25 per cent hyaluronic acid, 70–75 per cent heparan sulphate, and only 3–5 per cent chondroitin or dermatan sulphates, similar to that synthesized in vivo . No GAG was present in the secretory material, suggesting that all the GAG synthesized was destined for the basement membrane or cell surface.
Characterization of methyl mercury in dental wastewater and correlation with sulfate-reducing bacterial DNA

Dental wastewater (DWW) was collected over two months from a 12-chair clinic and a single-chair office to identify conditions that may affect Hg methylation. DWW was settled for 24 h and samples were collected from the top and bottom of the supernatant to simulate a range of particles that may escape in-line traps. Total Hg spanned 5 orders of magnitude (0.02-5000 microM), following a log-normal distribution with p10, p50, and p90 concentration values of 0.24, 31 and 4000 microM, respectively; typically well in excess of free aqueous Hg solubility. Methyl Hg was present in high levels (2-270 nM), also following a log-normal distribution with p10, p50, and p90 concentration values of 2.8, 17, and 100 nM, respectively. There were no statistically significant differences (90% CI) in p50 methyl Hg or total Hg between the clinic and office. Methyl Hg was predicted from total Hg data by (+/- 95% CI): Log (Me-Hg) = 0.33 (+/- 0.06) x Log (T-Hg) - 2.27 (+/- 0.13). Total methyl Hg from DWW to U.S. wastewater collection systems is estimated to be 2-5 kg yr(-1). Equilibrium speciation modeling predicted that DWW Hg was primarily in sulfide-Hg complexes, except at high total Hg levels where organo-Hg complexes become significant. DNA extracts amplified by quantitative polymerase chain reaction with primers for total eubacteria and sulfate-reducing bacteria (SRB) indicated that the total eubacterial DNA was composed primarily of SRB, and highly significant correlations were found between methyl Hg and both amplified Desulfobacteraceae (p < 0.0001) and Desulfovibrionacaea DNA (p < 0.00001). Both are known Hg methylators. In marked contrast, there was no significant correlation between methyl Hg and amplified Desulfobulbus DNA, a genus generally not known to methylate Hg at high rates. These results strongly suggest that SRB are implicated in DWW Hg methylation.
Glycogen Deposition in the Liver Induced by Cortisone: Dependence on Enzyme Synthesis

The deposition of liver glycogen in starved rats given a single dose of cortisone is inhibited by puromycin and actinomycin. The former agent interferes with induced enzyme formation in general, and the latter with the cortisone-induced rise in liver enzyme levels. The results suggest that the regulatory eJffect of cortisone on carbohydrate metabolism may be brought about -by its action on the cellular concentration of certain enzyme proteins.
General principles governing the behavior of the microcirculation.

T HE successful achievement of tissue homeostasis is dependent upon regulatory mechanisms which are unique to the terminal vascular bed, and function independently of the remainder of the circulatory system. In general, the reactions of the peripheral blood vessels fall into three main categories: the maintenance of blood pressure (arteries and arterioles) ; the local regulation of blood flow within the tissue proper (terminal arterioles, precapillary sphincters and capillaries) ; and the return of the blood to the heart (the muscular venules and veins). In the general area of blood pressure regulation, two attributes of the larger arteries and arterioles are of importance. The general compliance or distensibility of the vessels, an intrinsic physical property governed in the main by its elastic tissue elements [I] ; and active changes in caliber mediated by the contractile smooth muscle elements [2]. There are a number of important differences in the basic properties of the smaller blood vessels as conduits in comparison with larger vessels. The distensibility of the muscular arterioles is a function of the prominent smooth muscle component. As a consequence, the tension-length relationship in the small vessels does not follow purely physical laws, since the muscle tone, unlike the elastic tissue factor in large blood vessels, represents a variable and an actively modulated property [3]. The loss of its connective tissue investment removes the small blood vessels from the status of a separate compartment and makes the vessel wall an integral part of the tissue. This contingency exposes the smooth muscle and endothelial elements to the environmental influence of the tissue metabolic milieu and introduces a new set of regulatory mechanisms. A waning in the regulatory influence of the sympathetic nervous system becomes apparent concurrent with the structural alterations [3]. Not only are the vessels in the terminal vascular bed under the predominant influence of humoral factors but, as a consequence of their extreme sensitivity to vasoactive agents, show a considerable latitude of independence of the remainder of the circulatory system [5l. One other feature distinguishes the microcirculation. The local introduction of vasoactive principles gives to this agency the ultimate control of the tissue circulation, to the extent that local factors can override systemic stimuli, even when they are of maximal intensity. The sympathetic nervous system, thus, serves to modulate the changes in peripheral circulation, integrating them with the activity of the larger blood vessels.
A method of verifying the coefficients an and bn of the Mie theory of light scattering by nonabsorbing isotropic spheres

Abstract The coefficients an and bn of the terms of Mie's series for the intensity of electromagnetic radiation scattered by isotropic spheres are complex numbers. If the spheres are nonabsorbing, van de Hulst showed that each value of an and bn lies on a circle in the complex plane with its center at ( 1 2 , 0i) and a radius of 1 2 . This relationship provides a simple method of checking the self-consistency of values of the coefficients. If all are rounded to the same number of significant figures, each value of Im(an) and Im(bn) and 93% of those of Re(an) and Re(bn) may be verified with an uncertainty of two to ten times the rounding-off error. Over the circumference of the circle between (0.445, ±0.497i) and (0.555, ±0.497i), the uncertainty in Re(an) and Re(bn) increases tenfold for each tenfold decrease in | Re (a n ) − 1 2 | or Re (b n ) − 1 2 ; this fortunately corresponds to a tenfold decrease in the percentage of coefficients involved.
The Role of Rural Communities in the Postsecondary Preparation of Low-Income Students.

In the past decade, rural education has been critiqued for contributing to brain drain and social stratification that saps the human, social, and economic resources of rural communities. This article, based on an investigation of six small rural school districts in the same state, offers an alternative view of the role of community groups and individuals in the academic preparation and postsecondary aspirations of local low-income students. From the accounts of 79 school and community residents, we developed a typology that categorizes local stakeholders by their involvement in three common functions: program support, program directing, and program initiation/administration. These proeducational activities, in combination, support the necessary tasks of qualification, graduation, application, and aspiration. Results not only increase understanding about the ways rural communities support educational preparation, but also clarify the links between particular community behaviors and the completion of essent...
Fracture prediction for the proximal femur using finite element models: Part I--Linear analysis.

In Part I we reported the results of linear finite element models of the proximal femur generated using geometric and constitutive data collected with quantitative computed tomography. These models demonstrated excellent agreement with in vitro studies when used to predict ultimate failure loads. In Part II, we report our extension of those finite element models to include nonlinear behavior of the trabecular and cortical bone. A highly nonlinear material law, originally designed for representing concrete, was used for trabecular bone, while a bilinear material law was used for cortical bone. We found excellent agreement between the model predictions and in vitro fracture data for both the onset of bone yielding and bone fracture. For bone yielding, the model predictions were within 2 percent for a load which simulated one-legged stance and 1 percent for a load which simulated a fall. For bone fracture, the model predictions were within 1 percent and 17 percent, respectively. The models also demonstrated different fracture mechanisms for the two different loading configurations. For one-legged stance, failure within the primary compressive trabeculae at the subcapital region occurred first, leading to load transfer and, ultimately, failure of the surrounding cortical shell. However, for a fall, failure of the cortical and trabecular bone occurred simultaneously within the intertrochanteric region. These results support our previous findings that the strength of the subcapital region is primarily due to trabecular bone whereas the strength of the intertrochanteric region is primarily due to cortical bone.