cssi/SciSciGPT-SciSciNet huggingface dataset:
CALM: Continuous Adaptive Learning for Language Modeling.

Training large language representation models has become a standard in the natural language processing community. This allows for fine tuning on any number of specific tasks, however, these large high capacity models can continue to train on domain specific unlabeled data to make initialization even more robust for supervised tasks. We demonstrate that in practice these pre-trained models present performance deterioration in the form of catastrophic forgetting when evaluated on tasks from a general domain such as GLUE. In this work we propose CALM, Continuous Adaptive Learning for Language Modeling: techniques to render models which retain knowledge across multiple domains. With these methods, we are able to reduce the performance gap across supervised tasks introduced by task specific models which we demonstrate using a continual learning setting in biomedical and clinical domains.
Assessing the Threat of Incel Violence

In recent years, increasingly serious incidents of violence have been committed by young men predominantly in the United States and Canada who self-identify as incels (involuntary celibates). Altho...
Synthetic promoter based azide biosensor toolkit to advance chemical-biology

Abstract Real-time azide or azido-functionalized molecular detection inside living cells using bioorthogonal chemistry-based approaches has been revolutionary to advancing chemical-biology. These methods have enabled diverse applications ranging from understanding the role of cellular glycosylation pathways, identifying diseased cells, and targeting delivery of azido-based therapeutic drugs. However, while classical techniques were applicable only to in-vitro detection of such functional groups, even recent bioorthogonal based-detection methods require expensive sensing reagents and also cannot selectively identify inorganic azide. Here, we report an in-vivo synthetic promoter based azide biosensor toolkit to selectively detect azide anions. A promiscuous cyanate-specific promoter was engineered to detect azide and rapidly induce expression of green fluorescent protein (GFP) in Escherichia coli. Our synthetic azide operon allows highly-tunable GFP expression, outperforming the classic lac-operon, and also offers an alternative low-cost protein expression system. Finally, we showcase the utility of this toolkit for in-vivo bioorthogonal reaction biosensing and glycoengineering based applications.
An Architecture for Advanced Networking Technology for Integrating Communications in Space

In the current model of space missions, the communications system can account for a significant percentage of the overall cost. Many times, an entire communications system is developed for each new mission. The Advanced Networking Technology for Integrating Communications in Space project (ANTICS) is focused on the development of a commodity communications capability that will allow new space missions to significantly reduce costs and provide a more robust ground infrastructure to support those missions. This paper describes a new architecture for ground-to-space communications based on the Long-Term Evolution (LTE) protocol suite that forms the primary basis for terrestrial cellular communications. By leap-frogging the state-of-the-art for space communications, this approach puts a more robust evolution path for space communications in place and provides space missions with a flexible, IP-based infrastructure capable of supporting a wide variety of applications. This paper provides the requirements and concepts of operation for space communications with LTE, an overarching architecture to utilize LTE in space mission communication systems, and the potential novel applications that are enabled by moving space communications towards the commercially successful LTE protocol suite.
Sequential Possibilistic Local Information One-Means Clustering For Image Segmentation

Clustering has long been applied to the problem of image segmentation. Because of spatial connectivity constraints, several approaches have been proposed to incorporate local consistency into image segmentation by clustering. One popular method, the fuzzy local information c-means (FLICM) has been shown to produce good segmentation results. Like the fuzzy cmeans (FCM) from which it is derived, FLICM requires that pixels "share" memberships across clusters, that is, the memberships of a pixel across all clusters need to sum to one. The possibilistic c-means (PCM) clustering was introduced to relax the membership sum-to-one constraint of the FCM, and has found a place in the clustering universe, particularly in those situations where the data contains outliers, is noisy, or highly overlapped. This paper extends the structure of FLICM to possibilistic versions for image segmentation. Two approaches are proposed. The first, called possibilistic local information cmeans (PLICM) inserts the local information term of FLICM into the basic PCM model. PLICM, like PCM, can produce coincident cluster centers. Recently, a sequential application of PCM (with c = 1) has been developed to mitigate negative effects of the co-incident cluster formation. Three algorithms form the family of sequential possibilistic 1-means (SP1M). These algorithms are extended to account for local information in image segmentation (SPLI1M). After development of the approach, experiments are performed on images which show that the SPLI1M family has superior performance in image segmentation over FLICM, PLICM and other clustering algorithms that don’t combine local spatial information of the image.
Systematic review and meta-analysis comparing arrival versus delayed vaccination of high-risk beef cattle with 5-way modified-live viral vaccines against BHV-1, BRSV, PI3, and BVD types 1 and 2

Bovine respiratory disease (BRD) is a major economic and welfare concern of the beef cattle industry. Various approaches to vaccination against the major viral pathogens have been investigated, including timing. It is thought that beef cattle entering feedlots may not be able to adequately respond to vaccination due to the stresses of shipping and processing. A meta-analysis was performed to compare the effectiveness of on-arrival vaccination to vaccination delayed 7 or more days following arrival, using a modified-live viral (MLV) vaccine against bovine herpesvirus-1 (BHV-1 ), bovine respiratory syncytial virus (BRSV), parainfluenza-3 (PI3), and bovine viral diarrhea types 1 and 2 (BVD 1 and 2), on outcomes of BRO morbidity, retreatment risk, and mortality. Eight studies were identified comparing vaccination timing in feedlot cattle via literature search. Mantel-Haenzsel risk ratios were calculated for each outcome, and Forest plots were constructed. In the studies identified, there was no difference in BRD morbidity risk, retreatment risk, or BRD mortality between calves vaccinated at arrival or delayed. Based on the data from the studies analyzed, it would not appear that there is an advantage or disadvantage in terms or morbidity, retreatment risk, or mortality in delaying vaccination.
On Family, Fieldwork, and Liquid Gold.

In this essay, I story my discovery of breastmilk markets and my subsequent fieldwork and research program in the milk banking industry. I discuss how my experience growing up as the oldest of six ...
Fat in College: A Social Overview

Fat college students struggle with many social barriers both at the academy and in the greater context of society. Individuals who are classified as overweight or obese are stigmatized as lazy or out of control and are less likely than non-fat people to make it to college (Crandall 1994). Much of the prejudice directed at fat individuals is based on incorrect and ill-researched assumptions about individual responsibility for weight and the impact of weight on health. The social acceptability of anti-fat attitudes makes it less likely for fat individuals to claim group identity even though this may be their best chance for social fit.
Role induction and caregiver strain : A structural equation approach

Using causal modeling, this study of 71 adult daughter caregivers of elderly parents examines direct and indirect relationships between two caregiver induction factors. caregiver reason for selection into the role and level of willingness to assume the role. The influence of caregiver reason for selection on level of willingness and post-induction caregiver strain is explored using structural equation modeling. Reults suggest caregivers who perceive no other alternative for care are less willing to provide care. When caregivcrs perceive no alternative to care, they report decreased levels of willingness and increased strain. Implications for practice and future research are presented.
The Effect of Relativistic Particle Beams on the Evolution of Supernova Envelopes: Self-Consistent Solutions

We consider the effect of a relativistic particle beam produced as part of the collapse process of a supernova core into a neutron star or black hole on the evolution of the expanding envelope. Relativistic bremsstrahlung is the dominant energy loss mechanism until the material through which the beam propagates becomes ionized. After an ionized channel is formed, plasma processes and inverse Compton losses become the dominant loss mechanisms. The energy loss processes associated with the beam impart significant momentum to the irradiated segments of the shell. This suggests a natural explanation for the asymmetric expansion of some supernovae, including SN1987a, and may account for the early mixing seen in that object. It also implies that some fraction of the X-ray light from very early in a supernova explosion originates in an inverse Compton emission process wherein relativistic electrons from the beam collide with optical photons from the expanding envelope. In this paper we present self-consistent solutions to the rate equations for the energy loss due to collective processes and calculate the momentum transferred to the envelope by the beam. We then comment on the expected X-ray emission from SNl987a using such a model (Beall 1979), and make estimates of the associated γ-ray flux.
ECM-stimulated signaling and actin reorganization in embryonic corneal epithelia are Rho dependent.

PURPOSE. The goal of this study was to investigate the role of the small guanosine triphosphatase (GTPase), Rho, in the corneal epithelial response to extracellular matrix (ECM) molecules. The avian corneal epithelial model was used to establish that Rho is required for actin reorganization and tyrosine phosphorylation of integrin-mediated signal pathway proteins. METHODS. Whole embryonic corneal epithelia were isolated without the basal lamina and either transfected with Rhospecific antisense oligonucleotides or treated with Clostridium botulinum C3 exoenzyme and then stimulated with fibronectin (FN) or collagen (COL). The epithelia were evaluated for actin reorganization and protein production including Rho protein levels and tyrosine phosphorylation with Western blot analysis. RESULTS. After an overnight transient transfection with antisense oligonucleotides, Rho protein levels were decreased more than 80%, and tyrosine phosphorylation of all integrinmediated signal transduction proteins was decreased compared with control epithelia. Intracellular Rho distribution did not change in the presence of antisense oligonucleotides; however, the amount of immunolabeled Rho decreased. Disrupting the signaling cascade with Rho antisense also blocked FN- and COL-stimulated actin cortical mat reformation. C. botulinum C3 exoenzyme, a pharmacologic agent that specifically causes adenosine diphosphate (ADP) ribosylation and inactivation of Rho, also blocked actin reorganization and tyrosine phosphorylation. In contrast, decreasing Raf protein levels did not change FN-mediated actin reorganization or tyrosine phosphorylation. CONCLUSIONS. Decreasing Rho protein or blocking its function inhibited ECM-stimulated actin reorganization and signal transduction, as measured by tyrosine phosphorylation. (Invest Ophthalmol Vis Sci. 2002;43:3181‐3189)
Characterization of the 5′-Flanking Region of the Gene for the α Chain of Human Fibrinogen

The 5′-flanking region of the gene coding for the γα chain of human fibrinogen was isolated, sequenced, and characterized. The principal site of transcription initiation was determined by primer extension analysis and the RNase protection assay and shown to be at an adenine residue located 55 nucleotides upstream from the initiator methionine codon, or 13,399 nucleotides downstream from the polyadenylation site of the gene coding for the chain. Transient expression of constructs containing sequentially deleted 5′-flanking sequences of the α chain gene fused to the chloramphenicol acetyltransferase reporter gene showed that the promoter was liver-specific and inducible by interleukin 6 (IL-6). The shortest DNA fragment with significant promoter activity and full response to IL-6 stimulation encompassed the region from -217 to +1 base pairs (bp). Although six potential IL-6 responsive sequences homologous to the type II IL-6 responsive element were present, a single sequence of CTGGGA localized from -122 to -127 bp was shown to be a functional element in IL-6 induction. A hepatocyte nuclear factor 1 (HNF-1) binding site, present from -47 to -59 bp, in combination with other upstream elements, was essential for liver-specific expression of the gene. A functional CCAAT/enhancer binding protein site (C/EBP, -134 to -142 bp) was also identified within 217 bp from the transcription initiation site. An additional positive element (-1393 to -1133 bp) and a negative element (-1133 to -749 bp) were also found in the upstream region of the α-fibrinogen gene.
Social Psychological Methods Outside the Laboratory

1 What is Meant by Non-Laboratory Research? 2 Why Study Social Psychological Processes Outside the Laboratory? 3 Field Experiments 4 Internet Research 5 Diary Methods 6 Ambulatory Assessment 7 Trace Measures 8 Conclusion
Multifield Galileons and higher codimension branes

In the decoupling limit, the Dvali-Gabadadze-Porrati model reduces to the theory of a scalar field $\ensuremath{\pi}$, with interactions including a specific cubic self-interaction---the Galileon term. This term, and its quartic and quintic generalizations, can be thought of as arising from a probe 3-brane in a five-dimensional bulk with Lovelock terms on the brane and in the bulk. We study multifield generalizations of the Galileon and extend this probe-brane view to higher codimensions. We derive an extremely restrictive theory of multiple Galileon fields, interacting through a quartic term controlled by a single coupling, and trace its origin to the induced brane terms coming from Lovelock invariants in the higher codimension bulk. We explore some properties of this theory, finding de Sitter like self-accelerating solutions. These solutions have ghosts if and only if the flat space theory does not have ghosts. Finally, we prove a general nonrenormalization theorem: multifield Galileons are not renormalized quantum mechanically to any loop in perturbation theory.
Effects of social cognitive demand on Theory of Mind in conversations of adults with traumatic brain injury.

Background: A requisite skill for successful conversation is the ability to adjust one's language according to contextual factors. Aims: This study examined one aspect of language use in context—the use of mental-state terms, i.e. words that communicate thoughts, beliefs or feelings—in conversations between adult males with and without traumatic brain injury (TBI) and familiar partners. Methods & Procedures: Participants were five males in the chronic stage of recovery following severe TBI and five male peers matched for age, conversing with friends. Conversational context was manipulated using conversation starters that were designed to induce differing levels of self-disclosure or intimacy, with the expectation that mental-state term use would increase when participants talked about more intimate topics. Outcomes & Results: Participants in both groups used more mental-state terms in more intimate conversations; however, adults with TBI did not increase their mental-state term use to the same extent as matched peers. Adults with TBI also used a significantly different pattern of mental-state term types across intimacy levels as compared with peers. Conclusions & Implications: These quantitative and qualitative differences may contribute to social conversation problems of adults with TBI.
Father participation in behavioral parent training for ADHD: review and recommendations for increasing inclusion and engagement.

Research on parenting has generally focused on mothers, with fathers’ parenting approaches and interventions for fathers being relatively less studied. To investigate the involvement of fathers in behavioral parent training (BPT), the literature on BPT for attention-deficit/ hyperactivity disorder (ADHD) was reviewed. A systematic review of this literature (N 32) indicated that the majority of research studies are composed of mothers as participants in treatment and raters of outcome (87% of reviewed studies did not include information on father-related outcomes). Present barriers to father participation in BPT (e.g., content of classes, characteristics of fathers) are discussed. Strategies for increasing father participation are offered and include establishing the expectation that fathers will be involved in treatment at initial clinical contacts, collecting treatment-related information from both parents, conducting BPT classes that focus on issues of direct relevance to fathers, and integrating parent– child interactions in recreational settings into BPT programs.
Stress modulation of drug self-administration: Implications for addiction comorbidity with post-traumatic stress disorder

Drug abuse and dependence present significant health burdens for our society, affecting roughly 10% of the population. Stress likely contributes to the development and persistence of drug use; for example, rates of substance dependence are elevated among individuals diagnosed with post-traumatic stress disorder (PTSD). Thus, understanding the interaction between stress and drug use, and associated neuroadaptations, is key for developing therapies to combat substance use disorders. For this purpose, many rodent models of the effects of stress exposure on substance use have been developed; the models can be classified according to three categories of stress exposure: developmental, adult nonsocial, and adult social. The present review addresses preclinical findings on the effect of each type of trauma on responses to and self-administration of drugs of abuse by focusing on a key exemplar for each category. In addition, the potential efficacy of targeting neuropeptide systems that have been implicated in stress responses and stress system neuroadaptation in order to treat comorbid PTSD and substance abuse will be discussed. This article is part of a Special Issue entitled 'Post-Traumatic Stress Disorder'.
Efficient iterative diagonalization of separable pseudopotential Hamiltonians

Abstract Iterative diagonalization techniques as well as Car-Parrinello molecular dynamics simulation using first principles pseudopotentials require the repeated calculation of matrix times vector products. We discuss a technique which reduces the number of operations for the separable part of the Hamiltonian expressed in plane waves from order NN at N el to order N In(N)N el where N is the number of plane waves, Nat the number of atoms, and N el the number of electrons.
Decreased scapular notching with lateralization and inferior baseplate placement in reverse shoulder arthroplasty with high humeral inclination.

Background: Scapular notching is a radiographic finding of unknown clinical significance following reverse total shoulder arthroplasty (RTSA). The purpose of this study was to determine how baseplate position affects the incidence of scapular notching and measure the clinical outcomes. Hypothesis: We hypothesized that low base plate position on the glenoid and new prosthesis design with a higher humeral inclination angle would decrease the incidence of notching at 2 years follow-up. Materials and methods: A total of 54 patients with an average follow-up of 30 months met inclusion criteria and underwent radiographic analysis of scapular notching and radiographic measures to determine glenoid component placement. Clinical measures including visual analog score, American Shoulder and Elbow Surgeons (ASES) scores, and range of motion (ROM) were prospectively collected. Results: Thirty-nine of the 54 patients had no notching. 7 had Grade 1 notching, 7 had Grade 2 notching, one had Grade 3, and one had Grade 4 notching. Notching was associated with higher placement of the glenoid component as measured by peg-glenoid rim distance and base plate distance. All patients with no evidence of notching at 1-year, continued to have no notching after multi-year follow-up. Clinical outcome measures including ASES scores, ROM, and visual analog pain scores were improved at follow-up. Conclusion: We concluded that lower neck-shaft angle and low baseplate positioning led to a low incidence of significant scapular notching as only 6 out of 57 (16%) patients had notching Grade 2 and above. At short-term follow-up, this RTSA results in excellent clinical outcomes and a significantly lower scapular notching rate than traditional techniques.
The ecological role of caudal lamellae loss in the larval damselfly, Ischnura posita (Hagen) (Odonata: Zygoptera).

Damselfly larvae may autotomize and regenerate any of their 3 caudal lamellae. At least one missing or regenerating lamella was evident in 50.1% of field collected Ischnura posita larvae. Lamellae loss during molting is very infrequent (1 out of 117 recorded molts). Laboratory trials indicate that conspecifics remove lamellae and that this process is density dependent. The percentage of larvae losing lamellae during 24 h trials ranged from 73.5 at the highest density tested to 17.3 at the lowest density. I. posita larvae are cannibalistic. The presence of lamellae reduces an individual's chance of being cannibalized. More than twice as many final instar lamellae-less larvae were cannibalized during 24 h trials than analogous individuals having 3 lamellae at experimental initiation. Costs are also associated with lamellae autotomy. 1) Although individuals without lamellae can swim they are more reluctant to release from a wooden stalk and swim when threatened (9% release) than are larvae with lamellae (29% release). Since swimming is part of their repertoire of anti-predator behaviors this behavioral shift should be detrimental. 2) Caudal lamellae function in O2 uptake. Trials were conducted with larvae having and not having lamellae in an experimental horizontal oxygen gradient system. Relative to larvae without lamellae, those with lamellae preferred deeper depths at PO2 values greater than 70 torr. Many lamellae-less larvae distributed themselves at the water surface throughout the range of PO2 values tested. Differential depth distribution between larvae with and without lamellae is highly significant (P < 0.01).
The myosin swinging cross-bridge model

No biological system has been studied by more diverse approaches than the actin-based molecular motor myosin. Biophysics, biochemistry, physiology, classical genetics and molecular genetics have all made their contributions, and myosin is now becoming one of the best-understood enzymes in biology.
Structural Basis for Cell Cycle Checkpoint Control by the BRCA1-CtIP Complex.

The breast and ovarian tumor suppressor BRCA1 has important functions in cell cycle checkpoint control and DNA repair. Two tandem BRCA1 C-terminal (BRCT) domains are essential for the tumor suppression activity of BRCA1 and interact in a phosphorylation-dependent manner with proteins involved in DNA damage-induced checkpoint control, including the DNA helicase BACH1 and the CtBP-interacting protein (CtIP). The crystal structure of the BRCA1 BRCT repeats bound to the PTRVSpSPVFGAT phosphopeptide corresponding to residues 322−333 of human CtIP was determined at 2.5 A resolution. The peptide binds to a cleft formed by the interface of the two BRCTs in a two-pronged manner, with phospho-Ser327 and Phe330 anchoring the peptide through extensive contacts with BRCA1 residues. Several hydrogen bonds and salt bridges that stabilize the BRCA1−BACH1 complex are missing in the BRCA1−CtIP interaction, offering a structural basis for the ∼5-fold lower affinity of BRCA1 for CtIP compared to that of BACH1, as determined ...
Bumped from the shuttle fleet: Why didn't Enterprise fly in space?

Although it has hardly been noted in historical or popular literature, NASA's surprising decision not to prepare the first space shuttle Enterprise for spaceflight deserves attention as a significant event in early shuttle history. The decision came at a stressful juncture when the space shuttle program was transitioning from research and development to production and operations; it was an early signal of a looming crisis in the program and also an indication of early shuttle-era space policy. This essay examines the changing status of Enterprise in the little-noticed period 1976 through 1978. Three main factors influenced the fate of Enterprise : (1) the evolution of shuttle engineering and design, (2) funding and schedule pressures on the shuttle program, and (3) shuttle fleet size policy. Decisions in these areas came together in late 1977, with the result that, soon after its debut, Enterprise lost its place in the shuttle fleet and never flew in space.
Pernicious anemia in the second decade of life

Summary A 13-year-old Caucasian boy who had pernicousanemia with normal gastric acidity and a normal gastric biopsy is described. Although these findings are characteristic of the congenital form of pernicous anemia, it is unlikely that he was born with absence of intrinsic factor since he was 13 years of age at the time symptoms of a deficiency of vitamin B12 developed.
Determination of decaborane by means of ferricyanide.

(1960). Determination of Decaborane by Means of Ferricyanide. American Industrial Hygiene Association Journal: Vol. 21, No. 4, pp. 312-315.
The Tools of Regional Development Policy

A number of federal programs have impacts on state or regional economic development. The discussion in this paper is limited, however, to the two which have regional development as their specific objectives, namely, the Economic Development Administration (EDA), a part of the US Department of Commerce, and the Appalachian Regional Commission (ARC). Both EDA and ARC were designed to deal with regions which, for one reason or another, failed to share in the robust national growth of the 1960's. EDA has relied overwhelmingly on investment in social overhead capital rather than in directly productive activities. The ARC, on the other hand, developed highways to assure development corridors. After the highways were assurred, the ARC shifted its emphasis to investment in human capital - primarily in health and educational facilities. Looking to the future, it is not clear that policies designed to deal with depressed areas when the national growth rate was high will be applicable to depressed areas created in part by a sharp reduction in the national growth rate. 3 tables, 8 footnotes. (SAC)
Method development for the determination of 52 pesticides in tobacco by liquid chromatography-tandem mass spectrometry.

Abstract A method using reversed phase liquid chromatography–electrospray ionization–tandem mass spectrometry was developed for the determination of 52 pesticides in tobacco. The influence of mobile phase additives was investigated to improve sensitivity and accuracy of the method and to reduce matrix effects. The tobacco extracts were purified via a Chem Elut partition cartridge by consecutive elution with pentane followed by dichloromethane. The two fractions were further purified by Florisil solid-phase extraction with acetone or diethyl ether elution. An additional dispersive solid-phase extraction step with primary–secondary amine led to decreased recoveries of several pesticides due to degradation or binding to the sorbent. The method was validated for the tobacco types Burley, Oriental and Virginia. The recovery rates of almost all pesticides ranged between 70 and 120%. The limits of quantification were below or near the 10 ng/g level. Few but significant differences between the tobacco types could be found regarding recovery and sensitivity.
Closure measurements of naturally initiating small cracks

The initiation and growth of cracks in smooth 2024-T3 aluminum specimens have been investigated using acetate replicas. Crack opening displacements were measured as a function of load at several positions along the crack as it grew across the thickness of the specimen and became a through-the-thickness crack of a few millimeters in length. Tests run for R-ratios of 0.5, 0.0 and -1.0 showed that closure loads were well predicted by Newman's (1984) model. It is noted that small cracks grow slightly faster than would be predicted by long-crack data, and it is suggested that effects other than plasticity-induced closure must be taken into account.
A review of M. S. Robertson's work

(1984). A review of M. S. Robertson's work. Complex Variables, Theory and Application: An International Journal: Vol. 3, No. 1-3, pp. 11-25.
Solution conformation of a cyclic neurokinin antagonist: A nmr and molecular dynamics study

The solution structure of a hexapeptide, cyclo(Gln-Trp-Phe-Gly-Leu-Met), which is a selective NK-2 antagonist, has been studied by a combination of two-dimensional nmr and molecular dynamics (MD) techniques. The simulation based on nmr and MD data resulted in the convergence to a family of structures. Free molecular dynamics for 50 ps in the presence of DMSO solvent molecules shows that the structure is energetically stable. One intramolecular hydrogen bond between the amide proton of Gin and the carbonyl oxygen of Gly was revealed. This result is consistent with the results from the measurement of the temperature coefficient of the amide protons. The extent of intermolecular hydrogen bonding between the amide protons of the peptide and DMSO was also revealed by the free MD simulation. The resulting structure of the cyclic peptide contains a variation type I′ β-turn in the Gly-Leu-Met-Gln segment. Comparison of the structure of this peptide with that of other NK-2 antagonist cyclic hexapeptides was made, and the activity of cyclic antagonists appears to be inversely related to the conformational rigidity of the cyclic peptides. © 1994 John Wiley & Sons, Inc.
Gender differences in perceptions of web-based shopping

Women have yet to welcome Web-based shopping as readily as men. A primary factor for this state is how men and women view shopping. Understanding those differences will help vendors address this vital pool of consumers.
Kirchhoff's approximation indiffractive optics

Kirchhoff's approximation is reviewed and applied to standard problems of diffractive optics. Despite a consistent definition the range of validity varies significantly depending on the application. Kirchhoff's approximation is also compared with alternative diffraction models.
LiDAR-Derived DEM and Raw Height Comparisons along Profile Corridor Gradients within a Forest

We compared field based and airborne LiDAR-derived profile corridor measurements across forest canopy types and terrain ranging from 37% to 49% slope. Both LiDAR-derived DEM and raw LiDAR point elevations were compared to field data. Primary objectives included examining whether canopy type or terrain slope influenced LiDAR-derived profile measurements. A secondary objective included comparing cable logging payloads based on field measured profile elevations to payloads based on LiDAR-derived elevations. Average RMSE elevation errors were slightly lower for profile point to LiDAR DEM values (0.43 m) than profile point to nearest LiDAR elevation point (0.49 m) with differences being larger when sites within forest clearings were removed from analysis. No statistically significant relationship existed between field measured ground slopes and associated profile point and LiDAR DEM elevation differences but a mild correlation existed when LiDAR raw point elevation differences were compared. Our payload analysis determined the limiting payload distance and had consistent results across study sites. The DEM-based profile outperformed the nearest point profile by 5% on average. Results suggest that forest analysts should consider using the nearest LiDAR DEM value rather than the nearest LiDAR point elevation for terrain heights at discrete locations, particularly when forest canopy occludes locations of interest.
RBACvisual: A Visualization Tool for Teaching Access Control using Role-based Access Control

This paper presents RBACvisual, a user-level visualization tool designed to facilitate the study and teaching of the role-based access control (RBAC) model, which has been widely used in companies to restrict access to authorized users. RBACvisual provides two graphical abstractions of the underlying specification. Policies can be input and modified graphically or using text-based files. Students can use an embedded Query system to answer commonly asked questions and to test their understanding of a given policy. A Practice subsystem is also provided for instructors to assign quizzes to students; the answers can be sent to the instructor via email. We also present the results of an evaluation of RBACvisual within a senior-level course on information security. The student feedback was positive and indicated that RBACvisual helped students understand the model and enhanced the course.
The special child in school-report on a paper

Dr. Seymour B. Sarason is in the Department of Psychology and the Psycho-Educational Clinic, Yale University. This is a report based on a recording of Dr. Sarason's paper which he presented at the Twenty-second National Conference of the Orton Society, Boston, 1971. (Dr. Sarason was unable to prepare a manuscript for publication as he had planned to do ; but his talk generated not only immediate interest and enthusiasm following its presentation at the Conference, but several urgent requests from subscribers to the Bulletin for copies of his remarks. For these reasons, and because we feel his talk to be of special relevance to other papers in this issue of the Bulletin, the staff has taken the liberty of preparing and publishing this report, and take full responsibility for it. We believe it accurately reflects Dr. Sarason's talk.)
The nitrobenzo [b] thiophenes

Syntheses, and infrared and nuclear magnetic resonance spectral data for the six mononitrobenzo[b] thiophenes are described. Sulfonation of benzo[b] thiophene has been demonstrated to produce the 2- and 3-isomers.
Photorefractive polymer dispersed liquid crystals

ABSTRACTOrganic photorefractive materials have received increasing attention for photonic applications due to their highperformance level and their ease ofprocessing. Here, we present functionalized polymer dispersed liquid crystalsthat exhibit strong photorefractive properties. Their properties are investigated by wave-mixing experiments andtheir performance compared with photorefractive polymers and photorefractive liquid crystals.Keywords: Liquid crystal, photorefractive, polymer, organic, nonlinear optics, holography, optical processing,photoconductor 1. INTRODUCTION Photorefraclive materials arc among the most sentive nonlinear optical materials since they exhibit large refractive indexchanges when exposed to low power laser beams.' The photorefractive effect is based on the build-up of a space-chargethrough the photoexcitalion of carriers and their transport over macroscopic distances. Transport can occur by eitherdiffusion of the carriers, if the excitation is nonuniform, or by drift, if an electric field is applied to the material. Chargeseparation results in a space-charge field that changes the refractive index of the material. This refractive index change is aphase replica of the initial light distribution. Thus, photorefractive materials are used as optical recording medium.Optical media that can record a grating, that is the interference pattern of two coherent laser beams, are in high demand.For real-time optical recording or processing applitions, the material must have a dynamic response. hi other words thelight-induced gratings should be erasable or be able to accommodate any changes in the light waves that are inducing them,in real time. Materials with such optical encoding properties allow for implementanon of a wide range of optical applicationsranng from reconfigurable interconnects, dynamic holographic orage, to optical correlation, image recognition, imageprocessing; and phase conjugation. Therefore, materials where the optical encoding is dynamic and based on a periodicmodulation ofthe refractive index are the focus of intense research.During its first twenty-five years of existence, the photorefractive effect was studied mainly in inorganic Crystals,
Chapter Five: The Role of Discourse

Ce travail constitue le cinquieme chapitre d'un ouvrage general portant sur l'expression de la temporalite au cours de l'acquisition d'une langue seconde. Cette etude generale prend en compte toutes les possibilites mises en oeuvre par la langue pour referer au temps. Ce chapitre, ainsi que les chapitres 3 et 4, s'inscrit dans le cadre d'une approche orientee vers la forme (alors que les chapitres 1 et 2 s'appuyent sur une approche orientee vers le sens). Il prolonge le chapitre precedent dans l'examen critique des etudes visant a tester l'acquisition du systeme aspecto-temporel en langue seconde. Dans ce cadre, l'A. s'interesse ici particulierement a la relation entre la structure du discours et la distribution de la morphologie aspecto-temporelle. Il se penche sur l'hypothese discursive et mene une etude critique des theories linguistique portant sur la structure narrative. Les donnees du corpus analysees au chapitre precedent (productions ecrites et orales de 16 apprenants), dans le cadre de l'hypothese aspectuelle, sont reutilisees ici afin de tester l'hypothese discursive. Ainsi l'A. compare l'influence de l'aspect et du discours et presente une integration de ces resultats. A cette fin, il s'appuie sur des narrations personnelles, impersonnelles et personalisees. Finalement, il examine de quelle maniere les recherches sur l'influence du discours peuvent etre etendues afin d'inclure des textes non narratifs
Characterization of wear modes in ion-implanted steel from auger measurements

Abstract Auger spectra and depth profiles are reported from nitrogen-implanted steel samples that have been worn for various times on a Falex lubricant tester modified for use as a wear tester. The effect of the nitrogen implantations (2.5×10 17 N 2 + ions cm −2 at 180 keV) is to decrease the wear rate by about an order of magnitude. The Auger results reveal details of how the nitrogen is worn away at various times and at various depths. Several wear models are examined to determine their predictions for both wear time and depth profiles. The non-uniform wear model without major diffusion is consistent with the data. A major finding is that the nitrogen is worn away in about 3 h; however, the much improved wear conditions remain unchanged for at least 15 h. Thus the nitrogen acts as the initiator of good wear conditions rather than the sustainer, as has often been discussed in the past.
CONTINUOUS KYNURENINE ADMINISTRATION DURING THE PRENATAL PERIOD, BUT NOT DURING ADOLESCENCE, CAUSES LEARNING AND MEMORY DEFICITS IN ADULT RATS

Cognitive dysfunctions, including deficits in hippocampus-mediated learning and memory, are core features of the psychopathology of schizophrenia (SZ). Increased levels of kynurenic acid (KYNA), an astrocyte-derived tryptophan metabolite and antagonist of α7 nicotinic acetylcholine and N-methyl-d-aspartate receptors, have been implicated in these cognitive impairments. Following recent suggestive evidence, the present study was designed to narrow the critical time period for KYNA elevation to induce subsequent cognitive deficits. KYNA levels were experimentally increased in rats (1) prenatally (embryonic day (ED) 15 to ED 22) or (2) during adolescence (postnatal day (PD) 42 to PD 49). The KYNA precursor kynurenine was added daily to wet mash fed to (1) dams (100 mg/day; control: ECon; kynurenine-treated: EKyn) or (2) adolescent rats (300 mg/kg/day; control: AdCon; kynurenine-treated: AdKyn). Upon termination of the treatment, all animals were fed normal chow until biochemical analysis and behavioral testing in adulthood. On the last day of continuous kynurenine treatment, forebrain KYNA levels were significantly elevated (EKyn +472 %; AdKyn +470 %). KYNA levels remained increased in the hippocampus of adult EKyn animals (+54 %), but were unchanged in adult AdKyn rats. Prenatal, but not adolescent, kynurenine treatment caused significant impairments in two hippocampus-mediated behavioral tasks, passive avoidance and Morris water maze. Collectively, these studies provide evidence that a continuous increase in brain KYNA levels during the late prenatal period, but not during adolescence, induces hippocampus-related cognitive dysfunctions later in life. Such increases may play a significant role in illnesses with known hippocampal pathophysiology, including SZ.
Thinking about China's Future

China's modernisation mission is enduring but there continues to be a large mismatch in China's view of the world and how the world views China. This rejoinder questions China's commitment to political reform, discusses the economic challenges facing China and wonders whether there is a distinct and unique China growth model. Assessing China's impact as a rising power on the international system, it critiques China's global diplomacy and the future of US–China relations. The rejoinder is more circumspect on these issues than Cui's original article.
Dynamic algebras: Examples, constructions, applications

Dynamic algebras combine the classes of Boolean (B ∨ ′ 0) and regular (R ∪; *) algebras into a single finitely axiomatized variety (B R ◊) resembling an R-module with “scalar” multiplication ◊. The basic result is that * is reflexive transitive closure, contrary to the intuition that this concept should require quantifiers for its definition. Using this result we give several examples of dynamic algebras arising naturally in connection with additive functions, binary relations, state trajectories, languages, and flowcharts. The main result is that free dynamic algebras are residually finite (i.e. factor as a subdirect product of finite dynamic algebras), important because finite separable dynamic algebras are isomorphic to Kripke structures. Applications include a new completeness proof for the Segerberg axiomatization of prepositional dynamic logic, and yet another notion of regular algebra.
Modulation of disk margin structure during renewal of cone outer segments in the vertebrate retina.

In the process of disk renewal in retinal cone outer segments (COSs), apical displacement of disks must be coupled to systematic reductions in disk area and perimeter in order to retain overall conical geometry. We have quantified these changes in disk area and perimeter segment lengths by morphometric analyses of cross sections of fully formed disks taken from basal to apical ends of COSs. Specifically excluded from these analyses are data arising from partial or incomplete disks within the COS, which do not conform to the conical geometry and which constitute a minor fraction of the COS disk population. Thus, our results address the long-range pattern of structural changes affecting the major population of disks along the length of the COS. Our data indicate that decreases in total disk margin length associated with apical displacement of fully formed disks are due to decreases in the length of the margin opposite the cilium, i.e., the open margin segment. In contrast, the average length of the closed margin segment remains constant or increases slightly in the apical direction. The open margins of frog COS disks have recently been shown to possess a distinctive lattice of membrane-associated components (Fetter and Corless: Invest. Ophthalmol. Vis. Sci. 28:646–657, '87). We have also examined COSs by the freeze-fracture, deep-etch technique for evidence of a mechanism whereby measured changes in open margin length may be accommodated while maintaining the overall organization of the open margin segments. In regions of membrane continuity between open margins and the COS plasma membrane, we have observed elevated ridges on the plasma membrane that (1) tend to lie parallel to the open margin segments, (2) have a similar axial spacing, (3) occasionally demonstrate interconnecting filaments similar to those of the open margin lattice, and (4) appear to have a particulate substructure. The mechanism proposed for reducing open margin length involves tangential displacement of the lateral edges of the open margin lattice to the adjacent plasma membrane. These shifted lattice domains initially give rise to the plasmalemmal ridges, which subsequently disassemble, and whose components become redistributed in the COS plasma membrane. These structural features of COS open margins suggest several revisions of our earlier model of disk morphogenesis (Corless and Fetter: J. Comp. Neurol. 257:24–38, '87), which was based on the margin structure of ROS disks alone. Eckmiller (J. Cell Biol. 105:2267–2277, '87) has recently proposed that partial disks observed within the COS represent sites of new disk formation. We evaluate the consequences of partial disk geometries for local remodelling of the open margin lattice and briefly outline an alternative interpretation of the partial COS disks that is fully consistent with available morphological data.
ISOLATION AND BIOLOGICAL PROPERTIES OF SECRETORY GRANULES FROM RAT ANTERIOR PITUITARY GLANDS

A method is described for the isolation of secretory granules from rat anterior pituitary glands. The method consists of differential and isopycnic gradient centrifugations, followed by filtration of the zones containing granules on Nuclepore filters to remove mitochondria. Highly purified granules were obtained as indicated by electron microscopy. Major parts of the thyrotropin (TSH) and adrenocorticotropin (ACTH) were recovered in a single fraction of granules as were follicle-stimulating (FSH) and luteinizing (LH) hormones. The somatotropin (STH) and prolactin (LTH) were recovered in separate granule fractions. The major parts of the six different hormones were associated with their respective granule fractions as shown by bioassays specific for each of the hormones. The diameters of granules in sections of intact rat pituitary glands and in isolated pellets were measured, and the means and ranges were in close agreement. These results contribute to the identification of the cell types which produce the different pituitary hormones.
On the Automatic Determination of Light-Curve Parameters for Cepheid Variables

A computerized algorithm for the automatic detection of Cepheid variables and for the estimation of their periods, amplitudes, and mean magnitudes from sparse data sets is presented. It is intended to be suitable for use in such programs as the measurement of Cepheid distances to external galaxies, for example with the Hubble Space Telescope. The reliability of the algorithm is tested by application to new photometric reductions of pre-repair HST images of the nearby Sdm galaxy IC 4182, with comparison to published analyses of the same data (Saha et al. 1994, ApJ, 425, 14).