cssi/SciSciGPT-SciSciNet huggingface dataset:
Efficient discovery of visible light-activated azoarene photoswitches with long half-livesusing active search

Photoswitches are molecules that undergo a reversible, structural isomerization after exposure to different wavelengths of light. The dynamic control offered by molecular photoswitches is favorable for applications in materials chemistry, photopharmacology, and catalysis. Ideal photoswitches absorb visible light and have long-lived metastable isomers. We used high throughput virtual screening to predict the absorption maxima (λmax) of the E-isomer and half-lives (t1/2) of the Z-isomer. However, computing the photophysical and kinetic properties of each entry of a virtual molecular library containing 103–106 entries with density functional theory is prohibitively time-consuming. We applied active search, a machine learning technique to intelligently search a chemical search space of 255991 photoswitches based on 29 known azoarenes and their derivatives. We iteratively trained the active search algorithm based on whether a candidate absorbed visible light (λmax > 450 nm). Active search was found to triple the discovery rate compared to random search. Further, we projected 1962 photoswitches to 2D using the Uniform Manifold Approximation and Projection (umap) algorithm and found that λmax depends on the core, which is tunable with substituents. We then incorporated a second stage of screening with to predict the stabilities of the Z-isomers for the top 1% of candidates. We identified four ideal photoswitches that concurrently satisfy λmax > 450 nm and t1/2 > 2 hours; the range of λmax and t1/2 range from 465 to 531 nm and hours to years, respectively.
Updates to Good Practices for Estimating Area and Assessing Accuracy of Land Cover and Land Cover Change Products

While satellites have been collecting data since the 1970s, the remote sensing technology has exploded over the last decade, with the number of remote sensing instruments being far greater than ever before. Easy access to powerful computing platforms that give users direct access to the vast archives of satellite data, have created a situation where making maps and other spatial datasets has never been easier. This development is welcomed and gives geographical sciences an unprecedented potential to contribute to decision-making and policy. However, mapping complex and often spatially continuous surface conditions into a set of discrete map categories is bound to result in some of the map units being erroneous. The magnitude of errors will determine the reliability, usage, and interpretation of the map, which is why map users and producers have a direct interest in communicating and understanding the quality of maps. The quality of maps has traditionally been communicated via a so-called accuracy assessment, which results in measures of map accuracy based on the comparison of the map and a sample of observations of reference conditions on the land surface. While accuracy assessments are important and valuable, an analysis that ends with measures of map accuracy -- being it overall map accuracy or class-specific -- merely shows that the map is more or less incorrect (the very unlikely event of achieving 100% accuracy excluded). In policy and decision-making context, remote sensing is often used to quantify various phenomena on the land surface, such as the area of deforestation or urban expansion; but the presence of errors in remote sensing-based maps prevents the estimation of area directly from the map (“pixel counting”). As stated in the GFOI Methods & Guidance Document [1]:
Developmental Psychopathology and the Diagnosis of Mental Health Problems Among Youth

Recent years have evidenced a tremendous increase in research using a developmental psychopathology framework to examine clinical diagnoses among youth. Despite this increase, a relative dearth of literature systematically examines the development of co-occurring conditions among youth. In this introduction to the Special Issue on comorbidity among youth, we suggest that a developmental psychopathology perspective can provide an important foundation for the diagnosis of mental health problems among youth. As a potential framework for future investigations, we consider several developmental psychopathology principles that can inform assessment and diagnosis among youth psychological disorders. We use these principles as a foundation for considering co-occurring psychological disorders and provide potential explanations for comorbidity that can be addressed in future research that uses a developmental psychopathology perspective.
When Community Fails to Transform: Raveling and Unraveling a “Community of Writers”

This paper examines the importance of the notion of community in the practices of a remedial writing class at an urban university. Although labeled by their teacher as a “community of writers” this group did not write, and its members were judged by their university as failed writers. Their story illustrates the high value placed on the idea of community in school, its vulnerable nature and the fundamental conditions necessary to building its resilience. Implications for the role of community in remediation in higher education are noted in light of the failure of this group to form and sustain practices of community that might have supported their becoming successful writers.
An exercise in graph theory

We define a function that finds a path between two given nodes of a given directed graph, if such a path exists. We prove the function terminates and we prove that it is correct. Aside from illustrating one way to formalize directed graphs in ACL2, this chapter illustrates the importance of the user’s decomposition of a problem into mathematically tractable parts and the importance of defining new concepts to formalize those parts. Our proof involves such auxiliary notions as that of a simple (loop-free) path, the process for obtaining a simple path from an arbitrary path, and an algorithm for collecting all simple paths. The algorithm we analyze is a naive one that executes in time exponential in the number of edges. This chapter requires no specialized knowledge of graph theory; indeed, the main thrusts of the chapter have nothing to do with graph theory. They are: to develop your formalization skills and to refine your expectations of what a formalization will involve. Appropriate expectations of a project are often the key to success.
Humoral immune responses against gonadotropin releasing hormone elicited by immunization with phage-peptide constructs obtained via phage display.

Abstract Phage display is based on genetic engineering of phage coat proteins resulting in fusion peptides displayed on the surface of phage particles. The technology is widely used for generation of phages with novel characteristics for numerous applications in biomedicine and far beyond. The focus of this study was on development of phage-peptide constructs that stimulate production of antibodies against gonadotropin releasing hormone (GnRH). Phage-peptide constructs that elicit production of neutralizing GnRH antibodies can be used for anti-fertility and anti-cancer applications. Phage-GnRH constructs were generated via selection from a phage display library using several types of GnRH antibodies as selection targets. Such phage constructs were characterized for sequence similarities to GnRH peptide and frequency of their occurrence in the selection rounds. Five of the constructs with suitable characteristics were tested in mice as a single dose 5 × 10 11 virions (vir) vaccine and were found to be able to stimulate production of GnRH-specific antibodies, but not to suppress testosterone (indirect indicator of GnRH antibody neutralizing properties). Next, one of the constructs was tested at a higher dose of 2 × 10 12 vir per mouse in combination with a poly(lactide- co -glycolide) (PLGA)-based adjuvant. This resulted in multifold increase in GnRH antibody production and significant reduction of serum testosterone, indicating that antibodies produced in response to the phage-GnRH immunization possess neutralizing properties. To achieve optimal immune responses for desired applications, phage-GnRH constructs can be modified with respect to flanking sequences of GnRH-like peptides displayed on phage. Anticipated therapeutic effects also might be attained using optimized phage doses, a combination of several constructs in a single treatment, or application of adjuvants and advanced phage delivery systems.
Politics of Language Flow in West Africa

My previous work has looked at discrete language groups in Africa, and this paper begins a new project that examines citizen connection through lingua francas. Using ArcGIS technology and data from Ethnologue and Afrobarometer, I am tracing the spread of 8 languages in four countries in West Africa: Wolof and French in Senegal, Akan and English in Ghana, Dioula and French in Cote dIvoire and Krio and English in Sierra Leone. Not only do we want to know what languages are spreading (data for which are very hard to come by!), but we want to know why they are doing so. I have narrowed the causal factors I want to investigate to three: war, urbanization, and schooling. I hypothesize that wars and urbanization are much more important determinants of language spread than is education. This is because, as will be argued, governments have little incentive to spread official languages. To test this claim, I am gathering baseline information for each language in 1960 and comparing it to the spread of these languages in 2012. The intervening factors can be disaggregated by region and district, revealing which causal factors are more consequential.
Fine structure of transected interganglionic connectives and degenerating axons of wax moth larvae.

Interganglionic connectives of Galleria mellonella larvae were surgically isolated from the rest of the central nervous system, and the pieces were examined 3, 5, and 9 days later. Four categories of axoplasm fine structure were observed, and it is postulated that these represent progressive stages of degeneration. Axons resembling those in unoperated, lightly spun-up larvae constitute category I. Early axon degeneration (category II) is characterized by closely packed assemblages of mitochondria, neurotubules, and small vesicles. Later (category III), dense bodies, myeloid bodies, and autolytic bodies predominate, while mitochondria, small vesicles, and neurotubules diminish in abundance. In category IV axons nearly all organelles have disintegrated; large “empty vacuoles” occur, and the axolemma becomes discontinuous. Counts revealed that axon degeneration is progressive, but it is neither uniform, nor rapid. Unlike the axons, the neural lamella and much of the neuroglia remain unaltered. Comparisons are made to degenerative changes reported for axons of other insects and mammals.
The Glucose-Regulated Proteins (GRP78 and GRP94): Functions, Gene Regulation, and Applications

The knowledge of GRPs as molecular chaperones is rapidly evolving. It is anticipated that the GRPs will make special contributions in the areas of basic cell biology, biotechnology, and cancer biology. In particular, they may play a role as the prototype of a class of genes that are regulated by signal transduction pathways originating in the ER and traveling to the nucleus. GRP78 and GRP94 function as molecular chaperones and can bind to malfolded proteins and unassembled complexes. They are induced in response to stress, but once the stress is removed the GRPs are posttranscriptionally modified into biologically inactive forms. The promoters of the grp genes are highly conserved, with several CCAAT-like motifs and GC-rich regions. The high level of redundancy that exists in the mammalian grp promoters may act to ensure that the expression of the genes, both of which are single copy, is unlikely to be significantly lowered in the event of mutation. These genes are thought to be controlled by several transcription factors whose complex interactions with the grp promoters allow variable patterns of grp induction. The promoters of the grp genes constitutively express their gene products, and their promoter activities can be further enhanced in cellular environments of low glucose or oxygen. The grp78 promoter is known to retain its strong activity in differentiated and undifferentiated tissues. These features make it an attractive alternative to viral promoters for use in gene therapy. Gene therapy may also be useful in treating cancer in some cases, especially solid tumors. In these instances, GRP levels are already likely to be quite high. These high levels of GRPs may inhibit the efficacy of several anti-cancer treatments. Suppression of GRP induction, perhaps by anti-sense or ribozyme technology, may prove to be useful in conjunction with anti-cancer drugs to treat tumors.
A real options approach to valuing and negotiating licensing agreements

Abstract We apply real options modeling to a common pharmaceutical industry licensing arrangement to take into account various uncertainties and the flexibility value. The managerial flexibility is limited to the project abandonment option. We extend previous work by incorporating the phases required to bring the project from patent approval to market. We also incorporate a deterministic variable into the cash flow process that provides a realistic product lifecycle. We focus on the allocation of project value between licensor and licensee, i.e., the so-called “profit split” ratio (PSR) because it is commonly used in practice to negotiate terms. We find: (1) Ignoring the managerial flexibility in valuation may cause the licensee to either forego an acceptable deal or enter into an inferior deal. (2) The magnitude of project profitability as well as cost and sales uncertainty affects the licensor's bargaining power over compensation for granting abandonment flexibility to the licensee. (3) Managers must exercise care when estimating sales volatility because the flexibility value is more sensitive to sales volatility than it is to cost volatility. (4) Failure to incorporate the product lifecycle will produce suboptimal capital investment decisions.
Imaging of nontraumatic hemorrhage of the adrenal gland.

Nontraumatic hemorrhage of the adrenal gland is uncommon. The causes of such hemorrhage can be classified into five categories: (a) stress, (b) hemorrhagic diathesis or coagulopathy, (c) neonatal stress, (d) underlying adrenal tumors, and (e) idiopathic disease. Computed tomography (CT), ultrasonography (US), and magnetic resonance (MR) imaging play an important role in diagnosis and management. CT is the modality of choice for evaluation of adrenal hemorrhage in a patient with a history of stress or a hemorrhagic diathesis or coagulopathy (anticoagulant therapy). CT may yield the first clue to the diagnosis of adrenal insufficiency secondary to bilateral massive adrenal hemorrhage; such insufficiency is rare but life threatening. US is the modality of choice for evaluation of neonatal hematoma, and MR imaging is helpful for further characterization. MR imaging is also useful in the diagnosis of coexistent renal vein thrombosis. When an adrenal abscess is suspected, percutaneous aspiration and drainage un...
Turbulent prandtl number in thermally stratified shear flows of air

Abstract Turbulent Prandtl number and eddy viscosity distribution in the thermally stratified turbulent. boundary layer of an air flow are found to be functions of distance from the wall and thermal stabilities of the flow field. Turbulent Prandtl number in thermally stable shear flow of air is generally greater than that in thermally unstable shear flow of air.
Narrative Thinking As a Strategy Among Struggling Early Adolescent Readers and Writers

Abstract Students perceived as being “less proficient” readers and writers all too often receive language arts instruction that emphasizes decontextualized basic skills. Educators who advocate holistic forms of reading and writing instruction for all students encourage, instead, a consideration of reading and writing as sociocognitive meaning-making activities. This ethnographic study traces the narrative thinking strategies successfully used by adolescents in two self-contained special education classrooms as they made sense of their textbooks and composed original stories based on the subject matter they had been studying. Findings suggest that when students were encouraged to link the content from their textbooks with storied accounts from their own personal lives, they gained the energy and motivation needed for the cognitive demands of reading and writing. In addition, role-playing and composing original texts inspired by structured play also helped students tap into narrative thinking as a way of kn...
Narrow absorption line variability in repeat quasar observations from the Sloan Digital Sky Survey

We present the results from a time domain study of absorption lines detected in quasar spectra with repeat observations from the Sloan Digital Sky Survey Data Release 7 (SDSS DR7). Beginning with over 4500 unique time separation baselines of various absorption line species identified in the SDSS DR7 quasar spectra, we create a catalogue of 2522 quasar absorption line systems with two to eight repeat observations, representing the largest collection of unbiased and homogeneous multi-epoch absorption systems ever published. To investigate these systems for time variability of narrow absorption lines, we refine this sample based on the reliability of the system detection, the proximity of pixels with bright sky contamination to individual absorption lines, and the quality of the continuum fit. Variability measurements of this sub-sample based on the absorption line equivalent widths yield a total of 33 systems with indications of significantly variable absorption strengths on time-scales ranging from one day to several years in the rest frame of the absorption system. Of these, at least 10 are from a class known as intervening absorption systems caused by foreground galaxies along the line of sight to the background quasar. This is the first evidence of possible absorption line variability detected in intervening systems, and their short time-scale variations suggest that small-scale structures (~10-100 au) are likely to exist in their host foreground galaxies.
Elections: Debating the 1976 Debates: Establishing a Tradition of Negotiations

The 1976 presidential campaign brought televised presidential debates back to the presidential campaign after a 16-year absence. Like every presidential campaign debate, the 1976 debates were carefully planned and negotiated before they aired in the fall. The negotiators, much like the negotiators in 1960, gained control of the negotiations as well as the debates. This article culls together information from many sources to reveal how the 1976 debates were negotiated between the Ford and Carter campaigns as well as the League of Women Voters. This article is part of a larger project to develop a theory of presidential debate negotiation.
Pressure perturbations from geologic carbon sequestration: Area-of-review boundaries and borehole leakage driving forces

Abstract We investigate the possibility that brine could be displaced upward into potable water through wells. Because of the large volumes of CO 2 to be injected, the influence of the zone of elevated pressure on potential conduits such as well boreholes could extend many kilometers from the injection site—farther than the CO 2 plume itself. The traditional approach to address potential brine leakage related to fluid injection is to set an area of fixed radius around the injection well/zone and to examine wells and other potentially open pathways located in the “Area-of-Review” (AoR). This suggests that the AoR needs to be defined in terms of the potential for a given pressure perturbation to drive upward fluid flow in any given system rather than on some arbitrary pressure rise. We present an analysis that focuses on the changes in density/salinity of the fluids in the potentially leaking wellbore.
An application of the E-ε turbulence model for studying coupled air-sea boundary-layer structure

An E-e turbulence model is used to study air-sea interaction characteristics and turbulence structure using a coupled model for air-sea boundary layers. The E-e turbulence model consists of equations for the turbulent kinetic energy, the energy-dissipation, and for the turbulent exchange coefficient expressed in terms of turbulent kinetic energy and energy-dissipation. The energy-dissipation equations for the air-sea interface are solved analytically to obtain boundary conditions for energy-dissipation at the interface. The air-sea interaction and turbulence characteristics of the E-e model are compared with those of the mixing-length model and with available observations.
Physical and Chemical Properties of a Minespoil Eight Years after Reclamation in Northeastern Ohio

The potential of using flue gas desulfurization by-products (FGD) for the reclamation of acid minespoil was assessed in Tuscarawas County of Ohio, USA. In Treatment 1, 280 Mg ha -1 of FGD was incorporated into the graded spoil to a depth of 20 cm. In Treatment 2, 280 Mg ha -1 of FGD and 112 Mg ha -1 of yard waste compost were incorporated into the graded spoil (FGDC). In Treatment 3,112 Mg ha -1 of limestone was incorporated into the graded spoil and was covered with 20 cm of graded borrowed topsoil (BTS). Six cores and six bulk soil samples were obtained from each treatment for the 0- to 10-cm depth in summer 2002. From the 10- to 20-cm depth, only bulk soil samples were obtained. Bulk and core soil samples were also collected from an unreclaimed spoil (SP) and a nearby unmined soil (UMS). Among the three reclamation treatments, BTS showed better soil quality with higher soil organic C (28.5 Mg ha -1 ), water-stable aggregation (556 g kg -1 ), and mean weight diameter (3.2 mm) of aggregates than FGDC or FGD treatments. The FGDC had higher soil inorganic and organic C than FGD. However, saturated hydraulic conductivity (K S ), cumulative infiltration (I), infiltration rates at 5 min (is) and 2.5 h (i c ), and soil pH were similar among three treatments. Among treatments and controls, soil bulk density (p b ) was lower for FGD, FGDC, and UMS than BTS and SP; and water-stable aggregation and mean weight diameter of the aggregates was higher for UMS and BTS than FGDC, FGD, and SP for both depths. The I and i c were similar among UMS and treatments. Reclamation improved the soil quality with higher soil pH (7) and inorganic and soil organic C than in the SP. With respect to FGD, the soil organic C in FGDC increased at the rate of 0.64 Mg ha -1 yr -1 for the 0- to 10-cm depth. Overall, BTS was the best reclamation treatment. However, if topsoil is unavailable or transport is expensive, FGDC can be used as an effective reclamation material.
Lattice QCD simulations on big cats, sea monsters and clock towers

We present details of lattice QCD computations we are performing on the Cray XT series of computers, from BigBen – an XT3 hosted at the Pittsburgh Supercomputing Center (PSC) – through Jaguar (XT4) and Kraken (XT5) – which are hosted at the National Center for Computational Science (NCCS) and the National Institute of Computational Science (NICS), respectively, at Oak Ridge National Laboratory (ORNL). We discuss algorithmic tuning to make the computation more efficient and present some recent results.
Urinary cytokine and chemokine profiles across the menstrual cycle in healthy reproductive-aged women

Objective To assess the utility of urinary cytokines for monitoring reproductive function by considering detection, variation across the menstrual cycle, and relations with hormones. Design Longitudinal cohort study. Setting Academic institution. Patient(s) Healthy, reproductive-aged women with self-reported regular menstrual cycles and at least one observed ovulatory cycle (n = 248). Intervention(s) None. Main Outcome Measure(s) Urinary cytokines measured by 30-plex immunoassays in 3,550 biospecimens, and nested random-effects analysis of variance (ANOVA) and marginal structural models used to evaluate variability and relations with hormones. Result(s) For 24 of 30 evaluated factors, detectable levels were observed in at least 50% of urine samples. Interleukin-6 (IL-6), IL-8, IL-10, IL-15, granulocyte colony stimulating factor (G-CSF), hepatocyte growth factor (HGF), interferon-α (IFN-α), and RANTES (regulated upon activation normal T-cell expressed and secreted) levels varied significantly across the menstrual cycle. The proinflammatory factors IL-1β, IL-6, IL-8, and HGF were 1.5–3 times higher during menses than the late follicular phase. In marginal structural models, IL-1β, IL-6, IL-8 were associated with lower estradiol and progesterone concentrations. Conclusion(s) Variability during the menstrual cycle and correlations with reproductive hormone levels support a role of cytokines in the menstrual cycle; however, because of the limited variability for most cytokines considered, the utility of urine as a matrix for assessment of inflammation in menstrual cycle function appears limited for clinical purposes.
Adolescent Movements: Dating, Elopements, and Youth Policing in Ladakh, India

ABSTRACTIn India's northwest border region of Ladakh, norms of sexuality are changing, which is resulting in the emergence of new sexual practices, such as dating, ‘roaming’, and the dramatic elopements of Buddhist and Muslim youth. This has caused the emergence of youth policing the perceived sexual infractions of others, through targeting particular zones of intimacy – marriage, religious identity, and mobility. Yet, youth policing is uneven, targeting those considered to be the most ‘at risk’ for moral transgressions, including Buddhists, the elite, and those pursuing education. Ladakhi youth are in a tenuous position, where they negotiate their desires to be ‘modern’ with the community pressure to maintain a strong sense of cultural identity. This paper examines how youth navigate between tensions of modernity and culture, showing that they employ a range of strategic practices and tactics that provide space for expressing desires for modernity, while simultaneously securing cultural loyalty.
Unbalanced tension analysis for UHV transmission towers in heavy icing areas

Abstract Unbalanced tension is one of the most important controlling loads for the design of transmission towers in cold regions. It can be caused in some cases including non-uniform accreted ice, broken wires, ice shedding and galloping. Firstly, for the comparison of the unbalanced tensions and the inclinations of the suspension strings, the FEA method and the constant conductor length method were applied. The results by two methods are approximately well agreed. With the consideration of some design parameters of the transmission line, a seven continuous span FEA model of conductors and insulators was established. Secondly, under different load cases, the tensions and the unbalanced tensions of conductors were analyzed for the UHV suspension tower and tension tower in heavy icing areas. It shows that the load modes and the eccentricity of the accreted ice, as well as the wind velocity only have little effect on the unbalanced tensions. The transforming density method and 10 m/s of wind velocity are proposed for the analysis of the unbalanced tensions. When there are no elevation difference and span difference, the unbalanced tension of the UHV suspension tower increases with the ice thickness, the span length and the icing rate, and the calculated values for different ice thickness are lower than those of regulations. With the increasing of the elevation difference and the span difference, the ratios of the unbalanced tensions with and without elevation difference as well as span difference increase. However, the ratios of the unbalanced tensions with and without elevation difference as well as span difference decrease with the ice thickness. For tension towers, variations of the elevation difference and the span difference have little effect on the unbalanced tensions. Lastly, the calculated values of the unbalanced tension percentages of UHV transmission towers were compared with those of applicable regulations, some suggestions on the unbalanced tension values were proposed.
Greenhouse Gas Implications of Fleet Electrification Based on Big Data-Informed Individual Travel Patterns

Environmental implications of fleet electrification highly depend on the adoption and utilization of electric vehicles at the individual level. Past research has been constrained by using aggregated data to assume all vehicles with the same travel pattern as the aggregated average. This neglects the inherent heterogeneity of individual travel behaviors and may lead to unrealistic estimation of environmental impacts of fleet electrification. Using "big data" mining techniques, this research examines real-time vehicle trajectory data for 10,375 taxis in Beijing in one week to characterize the travel patterns of individual taxis. We then evaluate the impact of adopting plug-in hybrid electric vehicles (PHEV) in the taxi fleet on life cycle greenhouse gas emissions based on the characterized individual travel patterns. The results indicate that 1) the largest gasoline displacement (1.1 million gallons per year) can be achieved by adopting PHEVs with modest electric range (approximately 80 miles) with current battery cost, limited public charging infrastructure, and no government subsidy; 2) reducing battery cost has the largest impact on increasing the electrification rate of vehicle mileage traveled (VMT), thus increasing gasoline displacement, followed by diversified charging opportunities; 3) government subsidies can be more effective to increase the VMT electrification rate and gasoline displacement if targeted to PHEVs with modest electric ranges (80 to 120 miles); and 4) while taxi fleet electrification can increase greenhouse gas emissions by up to 115 kiloton CO2-eq per year with the current grid in Beijing, emission reduction of up to 36.5 kiloton CO2-eq per year can be achieved if the fuel cycle emission factor of electricity can be reduced to 168.7 g/km. Although the results are based on a specific public fleet, this study demonstrates the benefit of using large-scale individual-based trajectory data (big data) to better understand environmental implications of fleet electrification and inform better decision making.
Anomalous Magnetoresistance Behavior of Bismuth Antidot Arrays

Antidot arrays were formed in thin films of bismuth by the e-beam evaporation of the metal on the porous surface of porous anodic alumina templates. The magnetoresistance of the antidot array films was measured and compared to that of films deposited on glass slides. A significant difference in magnetoresistance behavior was observed, and this difference was attributed to the enhancement of the two dimensional weak antilocalization effect in the antidot arrays. Scattering rates were obtained by fitting the experimental results to the theoretical expression. The results indicate that the antidot morphology enhances the elastic scattering rate over the inelastic scattering rate.
Dosimetric characteristics of a commercial multileaf collimator.

The dosimetric characteristics of a multileaf collimator(MLC) retrofitted to a SL25 linear accelerator have been investigated. Central‐axis depth dose, surface dose, penumbra, beam flatness and symmetry, field size factors, beam transmission through leaves and/or diaphragms, and leakage between the leaves were measured. Quantitative measurements of all beam parameters show good agreement with the design specifications of the manufacturer. No changes were observed in flatness, symmetry, penumbra, and penetration for both 6‐ and 25‐MV photon beams when compared to the values for the standard collimator. No significant differences were observed in the penumbra as a function of leaf position. Transmission measurements in areas shielded by either X diaphragms or leaves plus diaphragms are less than 1% of dose within open field. The average leakage between leaves is about 2.5% for 6‐MV and 3.5% for 25‐MV photon beams. The peak value of the leakage at any point between leaves is less than 5%. The dosimetric features of shaped fields using the MLC are comparable to those of alloy shaped fields with the standard SL25 collimator.
A functional approach to efficient nitrogen use in crop production

Abstract Nitrogen fertilization is a critical component of most cropping systems. However, plant recovery of applied N is often only 50% or less. Low N-use efficiency is a contributor to groundwater contamination, eutrophication, acid rain, global warming, and farm insolvency. A method to improve N-use efficiency by plants is proposed where N availability from organic sources is compared with plant N uptake requirement over thermal time. From these relationships, N-use efficiency dynamics and plant N uptake from mineralized organic sources can be predicted. This will provide growers with information on the quantity and time to apply additional N for optimal yield and improved N-use efficiency.
Continuous Performance Test (CPT) of college students with ADHD, psychiatric disorders, cognitive deficits, or no diagnosis.

Objective/Method: The Conner’s Continuous Performance Test (CPT) was administered to four groups of adult college students who self-referred for comprehensive psychoeducational evaluation and received either no diagnosis (n = 30) or a diagnosis of ADHD (n = 26), a psychiatric disorder (n = 17), or various cognitive deficits (n = 22).Results: The groups did not differ with respect to age, sex, race, or IQ. Although the ADHD group made more CPT errors of omission, had longer response times, and showed greater variability in responding than the other three groups, these differences did not reach statistical significance when analyzed parametrically using standard scores. But when the pattern of scores across the groups was analyzed nonparametrically, significant and interpretable results emerged.Conclusion: The CPT reliably differentiated between individuals with ADHD and both normal college students and individuals with psychiatric diagnoses but not persons with learning/cognitive disorders.
Maternal hepatic and embryonic effects of 1,2,3,4-tetrachlorobenzene in the rat.

Abstract To assess possible maternal hepatic and reproductive effects of this uncharged, low molecular weight, lipophilic chlorinated benzene 0, 100, 300 and 1000 mg/kg/day of 1,2,3,4-tetrachlorobenzene (TCB) was orally administered to pregnant rats on days 9–13 of gestation and the animals were killed on day 14 of pregnancy. Phenobarbital and s-naphthoflavone were administered to other pregnant rats as positive hepatic controls. Maternal mortality ( sol7 19 rats ) was increased and body weight gain was greatly decreased in the 1000 mg/kg/day TCB group. Liver to body weight ratio and hepatic microsomal protein content were unaffected by any TCB treatment. On day 14 maternal NADPH-cytochrome c reductase activity was increased at 1000 mg/kg/day, while the maternal hepatic microsomal cytochrome P-450 content was significantly induced by both 300 and 1000 mg/kg/day of TCB. Microsomal N-demethylation of aminopyrine was increased from 2.6 to 4.0 amd 4.5 nmol/mg protein/min at doses of 300 and 1000 mg/kg TCB, respectively. However, maternal hepatic microsomal ethoxyresorufin O-deethylase activity was not consistently increased by TCB. Hepatic glutathione S-transferase activity towards 1,2-dichloro-4-nitrobenzene was increased only by the 1000 mg/kg/day TCB treatment. The rate of microsomal p-nitrophenol and phenolphthalein glucuronidation was increased by TCB administration. Embryonic growth was adversely affected by TCB treatment. Yolk sac diameter, embryonic crown-rump length, and head length were all decreased by treatment with 300 mg/kg/day TCB. This TCB treatment did not significantly elevate the number of dead or abnormal embryos.
Nondestructive evaluation of internal maturity of tomatoes using spatially offset Raman spectroscopy

Abstract This research explored the use of spatially offset Raman spectroscopy (SORS) for nondestructive evaluation of internal maturity of tomatoes. A Raman system using a 785-nm laser was developed to collect spatially offset spectra in the wavenumber range of 200–2500 cm −1 . The SORS measurements were conducted using a source-detector distance ranging from 0 to 5 mm with a step size of 0.2 mm. One hundred and sixty tomatoes at seven ripeness stages (i.e., immature green, mature green, breaker, turning, pink, light red, and red) were tested. The feasibility of the SORS for subsurface detection was examined by using a Teflon slab placed under outer pericarp slices of 5-mm and 10-mm thicknesses cut from green and red tomatoes. Raman signals from the outer pericarp layer and the Teflon layer were effectively separated by self-modeling mixture analysis of the offset spectra after fluorescence correction. Three Raman peaks due to carotenoids inside the tomatoes started showing at the mature green stage. Two peaks appeared consistently at 1001 and 1151 cm −1 , and the third peak was gradually shifted from 1525 cm −1 (lutein at mature green stage) to 1513 cm −1 (lycopene at red stage) owing to the loss of lutein and β-carotene and the accumulation of lycopene during tomato ripening. The Raman peak changes were evaluated by spectral information divergence (SID) with pure lycopene as the reference. The SID values decreased as the tomatoes ripened, and thus these values can be used to evaluate the internal ripeness of tomatoes.
Effects of increasing the magnitude of an alternative reinforcer on drug choice in a discrete-trials choice procedure

Rhesus monkeys were trained in a discrete-trials choice procedure and allowed to choose between food delivery (1-16 pellets; 1 g/pellet) and intravenous injections of cocaine (0.03-0.56 mg/kg/injection; N = 4) or procaine (1.0-10 mg/kg/injection; N = 4) during daily 3-h sessions. Injections were available as the alternative to food. When the amount of food available as the alternative to drug was held constant and dose of drug was varied, the frequency of drug choice and total drug intake increased in a dose-related fashion for both cocaine and procaine. For both drugs, when the amount of food available as the alternative to drug was increased and the dose of the drug was held constant, the frequency of drug choice and total drug intake decreased. Thus, increases in the magnitude of an alternative non-drug reinforcer decreased cocaine and procaine self-administration. Further, the results suggest that while increasing the magnitude of the alternative reinforcer decreased the potency of cocaine as a positive reinforcer, the reinforcing efficacy of procaine was decreased. Because drug use by humans typically occurs in a context in which other reinforcers are available, the present results are consistent with the hypothesis that drug self-administration by humans can be decreased by increasing the value of alternative positive reinforcers. In addition, these results suggest that the extent to which drug self-administration is sensitive to this manipulation varies across drugs.
Brainstem Strokes in a Pediatric Patient with Polyarteritis Nodosa: A Unique Case of CNS Vasculitis (P07.152)

Objective: To report a case of a series of brainstem infarctions in a pediatric patient with polyarteritis nodosa. Background Polyarteritis nodosa (PAN) is a medium and small vessel vasculitis that usually involves multiple organ systems. It is most common in adult males, peaking in the 6th decade of life. PAN is rare in children. CNS involvement is not uncommon; however, isolated cranial nerve palsies are extremely rare. Design/Methods: We reviewed the medical record of our patient and conducted a MEDLINE search to review the related literature. Results: An 11-year-old girl with a history of PAN, confirmed by temporal artery biopsy, presented with double vision at lateral gaze. Her exam revealed ptosis and limited adduction of the left eye. An MRI brain, CTA head, cerebral angiogram and lumbar puncture were normal. The patient was diagnosed with a partial CNIII palsy. Her double vision and ptosis spontaneously improved. Three weeks later, the patient presented with acute onset eye twitching, dizziness, gait instability, and nausea. Her exam revealed upbeat nystagmus of both eyes and an ataxic gait. Repeat MRI brain revealed an acute infarction in the medulla and a subacute, lacunar infarction in the left midbrain. Conclusions: A series of small-vessel brainstem infarctions in a pediatric patient with polyarteritis nodosa and otherwise negative work-up supports the diagnosis of CNS vasculitis. This is the first reported case of CNS vasculitis in a patient with PAN who was otherwise in remission and on maintenance therapy. There are few reports in the literature of PAN patients developing CNS vasculitis. Previous reports have demonstrated large vessel strokes or large T2-hyperintense lesions on imaging. Limited imaging technology in the past may have overlooked some small-vessel infarctions. Small-vessel brainstem infarctions, sometimes presenting with isolated cranial nerve palsies, may represent an unusual manifestation of CNS vasculitis. Disclosure: Dr. Noorollah has nothing to disclose. Dr. Abdelmoity has nothing to disclose. Dr. Hoeltzel has nothing to disclose.
Multiple encephalitogenic peptides of myelin basic protein in A. CA mice

Abstract Experimental allergic encephalmomyclitis (EAE) is an autoimmune disease of the central nervous system. It is mediated by T cells and is an animal model for the human disease multiple sclerosis. In most mouse strains that are susceptible to induction of EAE by myclin basic protein, a dominant peptide of myclin basic protein is recognized by encephalitogenic T cells. We report here the susceptibility of the A.CA strain (II-2′) to myclin basic protein induced EAE and that multiple peptides of myclin basic (1-11, 9-20, and 87-99) can induce disease in these mice. The finding that multiple epitopes of the same self-antigen can elicit EAE in an inbred strain of mouse raised the possibility of more heterogeneity in encephalitogenic peptides of the putative autoantigen in human disease than previous studies have suggested.
Electrical Responses of the Retinal Nerve and Optic Ganglion of the Squid

Recordings were obtained from the retinal nerves and optic ganglia of intact squid, which were maintained in good condition by perfusing their mantles with sea water. Only "on" discharges were found in the nerves, whereas "on" and "off" discharges as well as spontaneous activity and tactile responses were obtained from the ganglia.
Proteomic analysis of transducin β‐subunit structural heterogeneity

Partially purified transducin was resolved using two-dimensional gel electrophoresis (2-DE). Peptide mass fingerprinting of several different spots believed to correspond to the 37 kDa beta-subunit of transducin (T(beta)) was performed. Spots were excised and proteolyzed using modified trypsin. Matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS) was performed on the peptide mixture resulting from each spot. As many as six spots with different pI, ranging from 5.2 to 6.1, were observed when separated using 2-DE. MALDI peptide mass fingerprinting determined with high probability that all of the spots were the same gene product, guanine nucleotide-binding protein G(I)/G(S)/G(T) beta-subunit 1 (GNB1; T(beta1)). This suggested that post-translational modification was responsible for the differences in pI. Phosphorylation experiments showed that at least one T(beta1) spot was phosphorylated in vitro with [gamma-(32)P]ATP by an endogenous kinase. Treatment of T(beta) with alkaline phosphatase caused a large change in the spot pattern of T(beta), suggesting that phosphorylated T(beta) is a substrate for alkaline phosphatase. We conclude that T(beta1) constitutes over 99% of the T(beta) expressed in bovine rod outer segments and displays structural heterogeneity that is due to post-translational modification. We also conclude that some, but not all, of the heterogeneity observed is due to phosphorylation of Tb1.
Diffusional interactions at dual disk microelectrodes: comparison of experiment with three-dimensional random walk simulations

Abstract Three-dimensional random walk simulations were used to model the diffusional interactions between coplanar dual disk microelectrodes. Working curves for the dependence of shielding factor, collection efficiency, and amplification factor on the size of the gap between the electrodes were developed. The simulations showed that when the gap size was ⩾22 radii, the electrodes could be considered as independent and diffusionally isolated. Empirical equations for determining the gap size from simple shielding and generator–collector experiments were established. The simulation was used to model the collector electrode response for square waves of various frequencies applied to the generator electrode. Simulation results were in excellent agreement with the experimental results for several dual disk electrodes having various gap sizes.
Artificial crosses involving eastern North American silenes

Intentional interspecific crosses of North American species of Silene (Caryophyllaceae) have been uniformly successful. Crossability is high among western North American species; F, hybrids are vigorous and floriferous, but usually are wholly sterile (Kruckeberg 1955, 1961b, 1962). It is therefore worthwhile to find out whether high crossability and low fertility are to be found consistently throughout Silene. Should this correlation persist in large measure throughout the genus, then we would have a clearer insight into the nature and extent of taxonomic discontinuity in the genus.
Structural Properties of Type I Collagen Isolated from Chickens with Scoliosis

This study examines biochemically the Type I collagen isolated from skin of chickens that develop idiopathic scoliosis. Previous studies indicate a defect in collagen exists in these chickens. Alpha1 (I) and α2 chains were separated by gel filtration and carboxymethyl cellulose column chromatography and were then subjected to the analytical techniques of sodium dodecyl sulfate gel electrophoresis, Staphylococcus aureus V8 protease digestion, cyanogen bromide peptide mapping and amino acid analyses. In all categories, the scoliotic α1 (I) and α2 chains were identical to α chains isolated from normal chickens. These data suggest that the altered properties of collagen solubility and connective tissue stress relaxation seen in these scoliotic chickens are not a manifestation of an altered primary structure of the α chains or post-translational modification affecting chromatographic elution profiles or electrophoretic migration patterns.
Pulmonary function: the basics

Abstract The basics of pulmonary function testing in hospital laboratories are spirometry (FEV 1 , FVC, FEV 1 /FVC) and the carbon monoxide transfer factor (TLCO) and its components (KCO [∼TLCO/VA] and VA). A low FEV 1 /FVC ratio indicates intrapulmonary airflow obstruction. Distinction between intrapulmonary and extrapulmonary (upper airway) obstruction is given by maximal inspiratory and expiratory flow–volume curves. Other tests of lung mechanics are measurements of absolute lung volumes (TLC, FRC, RV) and maximal inspiratory and expiratory pressures against an obstruction at the mouth. Spirometry, lung volumes and mouth pressures can differentiate obstructive (low FEV 1 /FVC) and restrictive (normal FEV 1 /FVC, low TLC) patterns, detect hyperinflation (high TLC and FRC) and respiratory muscle weakness (reduced mouth pressures). The TLCO and KCO measure the integrity of the blood–gas barrier, being reduced in emphysema, interstitial lung diseases and pulmonary vascular pathology. The KCO (as % predicted) is high in extrapulmonary restriction (pleural, chest wall and respiratory neuromuscular disease), and in ‘loss of lung units' provided the structure of the lung remaining is normal. Thus, the KCO distinguishes extrapulmonary (high KCO) causes of ‘restriction' from intrapulmonary causes (low KCO). Significant hypoxaemia (low PaO 2 ) normally provokes compensatory hyperventilation and lowering of the PaCO 2 . Surrogates for arterial blood gases, avoiding arterial puncture, include pulse oximetry, ‘arterialized' capillary samples and transcutaneous PO 2 and PCO 2 probes.