cssi/SciSciGPT-SciSciNet huggingface dataset:
Characterization of the serotype e polysaccharide antigen of Streptococcus mutans.

Abstract The structure of the Streptococcus mutans serotype e polysaccharide was studied in order to determine the chemical basis of the immunological cross-reactions observed between it and the streptococcal group E polysaccharide. The chemical structure was established using methylation analysis, periodate oxidation, partial methanolysis and 13 C NMR spectroscopy. The polysaccharide was found to consist of a polyrhamnose backbone of alternating 2- and 3-linked α- l -rhamnose units and sidechain β- d -glucosyl units linked to the 2-position of rhamnose units in the backbone. This structure of the oligosaccharide repeating unit of the S. mutans serotype e polysaccharide was identical to that of the group-specific polysaccharide of group E Streptococcus . Possible explanations for the previously reported differences in these two polysaccharides are discussed.
DETERMINATION OF PHOTODISINTEGRATION CROSS SECTIONS INDEPENDENT OF DETECTOR EFFICIENCY AND PHOTON SPECTRUM.

Abstract For a nucleus of mass number A whose binding energy for a particle of mass X exceeds that of the nucleus with mass S ≈2 X , the differential cross section σ A (γ, X) can be obtained at one photon energy when neither the detector efficiency nor the photon energy spectrum is known, provided that the cross section σ S (γ, X) is known. For example, if X is a nucleon, S is the deuteron, and if X is a triton, S is 6 Li. At one specific energy the detector efficiencies and photon fluxes will cancel in the ration of the counting rates. If the relative detector efficiency and spectral shape of the photon beam are known, the comparison sets the absolute cross section scale over an extended energy region. Where efficiency and number of photons per interval are both thought to be known absolutely, the comparison point allows a check on self-consistency. When the spectral shape has been obtained from deuteron photodisintegration, secondary standards can be used if the detector efficiency is known. Alternatively the efficiency function can be checked by comparing several different nuclei. The method is applicable to photoneutron time-of-flight measurements.
Gait and cognition in Parkinson's disease: implications for rehabilitation.

An increasing awareness of the interaction between gait and cognition has occurred over recent time. This interaction is even more prominent in Parkinson ' s disease (PD), where the alteration of striatal dopamine deficiency places a greater emphasis on cognition to com- pensate for the gait disturbances seen in PD. This disser- tation aims to provide an insight into this interaction in PD and demonstrate how normal gait control mechanisms are altered in PD to more cognitive control. Evidence will be provided which demonstrates a shift between attention and automatic gait control mechanisms toward attention. In addition, it will be demonstrated that, because of the cognitive dysfunction that also occurs in PD, the capa- city to normalize gait still remains impaired and becomes more subject to the effects of external environmental influences. Further, a rationale will be provided to utilize this interaction in a more beneficial manner, to assist the attention control mechanisms to return gait towards nor- mal. This latter approach is applicable to all aspects of gait disorders in PD and forms a basis for possible inter- vention therapies. gait, in a constantly changing environment. In Parkin- son ' s disease (PD), this interaction with the environment is exaggerated, due to malfunction of the basal ganglia, resulting in cognitive processes playing a much larger role in gait regulation than normal. This review will present a theoretical basis for the impact of cognition on gait in PD, based on an understanding of normal gait control mecha- nisms and how malfunction in PD shifts control of gait to cognitive processes. This increased dependency on cogni- tion to improve gait in PD, makes gait more vulnerable to external influences. The impact of worsening cognition, brought about by the disease process itself, erodes com- pensatory effects. Our focus will therefore be on normal gait control mechanisms, their malfunction in PD and the impact of change in cognitive function. A detailed expla- nation of cognitive problems in PD will illustrate how this compensatory capacity can be eroded and how gait dete- riorates. Finally, clinical examples will be used to demon- strate how focused attention can improve gait, but at the expense of concurrent tasks.
Optical phase under deep turbulence conditions

The Markov approximation for waves in random media specifies that, under strong scintillation conditions, the optical field of unbounded waves has a normal probability distribution with zero mean. Using the coherence function provided by the Markov approximation, we calculate statistics of the phase of the optical field that accounts for the presence of multiple phase dislocations. We also develop and test a Monte Carlo model that generates the phase samples obeying these statistics. In contrast to numerous phase models described in the literature, this model generates discontinuous phase samples that contain optical vortices.
Characterization of exoplanet hosts - Implications for planet formation

Spectroscopic analysis of exoplanet hosts and the stellar sample from which they are drawn provides abundances and other properties that quantitively constrain models of planet formation. The program Spectroscopy Made Easy (SME) determines stellar parameters by fitting observed spectra, though line lists must be selected wisely. For giant planets, it is now well established that stars with higher metallicity are more likely to have detected companions. Stellar metallicity does not seem to affect the formation and/or migration of detectable planets less massive than Neptune, especially when considering only the most massive planet in the system. In systems with at least one planet less than 10 times the mass of Earth, the mass of the most massive planet increases dramatically with host star metallicity. This may reflect metallicity dependent timescales for core formation, envelope accretion, and/or migration into the detection zone.
Search Engines for Shape Selectivity

Zeolites have been used successfully for over 30 years to separate small molecules of almost identical physical and chemical properties, relying on shape differences such as normal from branched paraffins. Many zeolites have approximately circular windows and these are the only ones used in current applications. As of today, the structures of 176 zeolites are available; many of them have windows that may be described as elliptic or irregular, presenting many opportunities for shape selective catalysis or adsorption. A molecule approaching a window may take a number of orientations, and it is difficult to visualize the three-dimensional shape and the best fit to the window. Search engines are needed to accelerate the discovery of one or more zeolite windows that can separate a given pair of molecules. A great deal of progress has already been made to construct such search engines, and innovative industrial processes may follow in the future.
Inequity in the distribution of science and technology outcomes: a conceptual model

We propose a conceptual model to encourage systematic analysis of social equity issues of science policy. The model considers the relationships among several attributes of science and technology goods and services including the incidence of its impact, degree of concentration, and whether its consumption generates capacity for the individual or groups or is “hedonic,” that is, short term and diminishing rapidly in its effects. We discuss the implications of the model in terms of four quite different types of equity. We conclude by suggesting some respects in which the model could be employed to facilitate public policy and moral deliberations about the effects of science and technology.
Phase formation in coevaporated NiCr thin films

NiCr thin films with chromium concentrations spanning the 0–100% range were coevaporated onto NaCl substrates held at room temperature, 200 and 300 °C. Analytical transmission electron microscopy provided complete identification of the phases present in the films and characterization of their microstructures. Films of 0–40% Cr contained grains of the f.c.c. solid solution of chromium in nickel which, when formed at 200 or 300 °C, exhibited {111} twinning. Films of 50–70% Cr deposited onto room temperature substrates contained nanocrystalline σ phase, while larger grains of σ phase were found for elevated substrate temperature depositions. Films of 80% Cr, deposited onto 300 °C substrates, contained δ phase with the A15 structure in addition to the b.c.c. solid solution of nickel in chromium observed in films deposited onto lower temperature substrates. These observations are discussed in terms of thermodynamic calculations and electron phase considerations as they apply to the NiCr alloy system.
Presentation of cryptococcal capsular polysaccharide (GXM) on activated antigen‐presenting cells inhibits the T‐suppressor response and enhances delayed‐type hypersensitivity and survival

A hallmark of infection with Cryptococcus neoformans is depression of the immune system characterized by poor inflammatory responses and loss of delayed-type hypersensitivity (DTH) and antibody responses. T-suppressor cell (Ts) responses, elicited by the capsular polysaccharide (GXM) of the organism, are known to develop during infection. This study was undertaken to develop a method to inhibit the anti-GXM Ts response and thereby study the influence of the Ts response on immune responsiveness and survival in cryptococcosis. Antigen-presenting cells (APC), elicited with complete Freund's adjuvant (CFA), were treated in vitro with GXM (GXM-APC). The GXM-APC were injected intravenously into normal mice. These mice were resistant to induction of anti-GXM Ts cells when soluble GXM was administered in tolerogenic doses or when animals were infected with C. neoformans. Inhibition of the anti-GXM Ts response was specific to GXM as levan-APC did not inhibit induction of anti-GXM Ts cells. Inhibition of the anti-GXM Ts response could not be attributed to increased clearance of GXM due to induction of anti-GXM antibodies or other mechanisms. Anti-cryptococcal DTH responses were lost in mice by the second week of infection. However, treatment with GXM-APC, but not levan-APC, allowed mice to maintain their DTH response. GXM-APC pretreatment enhanced survival of infected mice compared with mice pretreated with levan-APC. These results show that GXM-APC induces immune responses that inhibit the induction of Ts responses and enhances DTH responses in infected mice. These responses correlate with enhanced survival after cryptococcal infection.
Corporate cooptation of organic and fair trade standards

Recent years have seen a substantial increase in alternative agrifood initiatives that attempt to use the market to curtail the negative social and environmental effects of production and trade in a globalized food system. These alternatives pose a challenge to capital accumulation and the externalization of environmental costs by large agribusiness, trading and retail firms. Yet the success of these alternatives also makes them an inviting target for corporate participation. This article examines these dynamics through a case study of the two most significant such food system alternatives—organics and fair trade—focusing on corporate involvement in establishing and renegotiating the standards undergirding these initiatives. We compare the development of and contestation over the standards for both certified organic and certified fair trade, with particular attention to the U.S. context. We provide a brief history of their parallel processes of rapid growth and market mainstreaming. We examine claims of cooptation by movement participants, as well as the divergences and similarities between the organic and fair trade cases. Analyzing these two cases provides useful insights into the strategic approaches that corporate firms have deployed to further capital accumulation and to defuse threats to their profit margins and to status quo production, pricing, labor, trading and retailing practices. It can also offer valuable lessons regarding the most effective means of responding to such counter-reforms and of protecting or reasserting the more transformative elements at the heart of these alternative systems.
Fast radiochemical separations for neutron-deficient short-lived nuclides

We review both simple and exotic radiochemical techniques used for the separation, purification, and analysis of neutron-deficient short-lived nuclides. These range from classical wet-chemical methods to automated and instrumental techniques. We give special attention to chemical adjuncts of the He-jet recoil-transport technique and to high-resolution mass spectrometry. We also review recent developments in biological applications, including13N production and use.
Rey II: Redesigning the Rey screening test of malingering

This study has redesigned the Rey 15-item Visual Memory Test (1964) by introducing more complex figures and by increasing internal logic and pattern redundancy. Standardized administrative procedures and rules for a simple qualitative scoring system were established. Performance on the original Rey continued to be significantly contaminated by ability components and illness while performance on the Rey II qualitative scoring system was not significantly related to intelligence, age, mental status or memory. The Rey II demonstrated improved face validity. Linear Discriminant Function Analysis indicated that the qualitative scoring system had a higher classification accuracy than the quantitative system on both instruments; the Rey II qualitative scoring system accurately detected 31% more college malingerers than the Rey quantitative and 21% more clinical malingerers than the Rey II quantitative. A malingering cut-off of two qualitative errors gave the Rey II a 79% higher sensitivity in the college malingerers and 29% higher specificity in the clinical population than the standard quantitative Rey cut-off of nine items. © 1997 John Wiley & Sons, Inc. J Clin Psychol 53: 757–766, 1997.
The Personal Statement

The coursework and clinical rotations have been completed with flying colors, and the US Medical Licensing Examinations has been aced—so why are many applicants to residency programs across the country still so anxious? This anxiety is caused in part by the daunting task of writing the “personal statement,” one of the required elements for the residency program admission process. Ideally, selection committees view the personal statement as a window into the thoughts, priorities, career commitments, and persona of the applicant. Thus, students invest a great deal of effort and seek assistance from faculty mentors, family members, peers, and even professional writers. Web sites provide guidance on how to compose the “best” personal statement, along with, in many cases, examples of “outstanding” personal statements. In addition, some medical schools provide guidelines, didactic sessions, and a list of do’s and don’ts for the personal statement. Original ideas that started with the applicant are modified by others until the statement appears to “fit” some ideal mold. The statement, which should have been the true articulation of the applicant’s own personal journey, dreams, and desires, turns into a team effort with the sole purpose of impressing the residency program directors and resident selection committees. Given thevarioussources ofinput,the question ofwhether the personal statement remains an authentic portrayal of the applicant must be raised. Moreover, because the personal statement is rarely crafted solely by the applicant, how muchvalueshould residencyprogramdirectorsandselection committees place on the process of selecting candidates for interviews and for residency positions? Even though the intent of the personal statement has been widely endorsed, in practice the statements have become homogeneous and lack distinguishing, substantive value. 1 Attempts to develop objective criteria by which to evaluate personal statements have been unsuccessful. 2 Any scoring of the personal statement is inherently subjective, and a review of the literature indicates that opinions of the value of the personal statement vary among specialties, with some ranking it high and others ranking it very low in importance. 2,3 Attempts to develop criteria for the statement as a means of identifying individuals to invite for an interview are ongoing. 4
Renormalization group analysis of permeability upscaling

The heterogeneity of the subsurface permeability is considered as the most influential factor in determining groundwater flow and the transport of toxic contaminants. Numerical simulators cannot handle the large grids required to represent the small-scale variability of permeability, and thus explicit estimates of the large-scale behavior in terms of coarse-grained parameters are often required. Perturbation formulations of the effective permeability are based on simplifying assumptions that are valid only for certain probability distributions and weak heterogeneity. A generalized perturbation ansatz that involves higher orders has been proposed (Gelhar and Axness, 1983), but to our knowledge its validity has not been rigorously proved before in three dimensions. In this work we propose a general upscaling formulation valid for strong heterogeneity, general permeability distributions, and media with impermeable zones. We show that the effective permeability is determined by the self-energy series of the permeability fluctuations at zero frequency. Using the diagrammatic representation, we obtain a Dyson equation that involves only irreducible diagrams of the proper self-energy series. We develop a renormalization group (RG) analysis for isotropic lognormal media that proves the generalized perturbation ansatz to all orders. We show that the RG result accurately estimates laboratory permeability measurements in limestone (strong heterogeneity) and sandstone (weak heterogeneity). We also propose an explicit RG estimate for the preasymptotic effective permeability. We compare our results with an approach based on a leading order Green's function expansion (Paleologos et al., 1996), which, however, requires intensive numerical computations. Finally, we investigate the relation between the RG expression and the algebraic means used in numerical upscaling.
Fanconi anemia in Ashkenazi Jews.

Fanconi anemia (FA) should be included among the genetic diseases that occur at high frequency in the Ashkenazi Jewish population. FA exhibits extensive genetic heterogeneity; there are currently 11 complementation groups reported, and 8 (i.e., FANCA, FANCC, FANCD1/BRCA2, FANCD2, FANCE, FANCF, FANCG, and FANCL) genes have been isolated. While patients may be from widely diverse ethnic groups, a single mutation in complementation group FA-C, c.711+4A>T (commonly known as IVS4+4A>T prior to current nomenclature rules) is unique to FA patients of Ashkenazi Jewish ancestry, and has a carrier frequency of greater than 1/100 in this population. In addition, a mutation (c.65G>A) in FANCA (FA-A is the most common complementation group in non-Jewish patients) and the mutation c.6174delT in FANCD1/BRCA2 are also unique to the Ashkenazi Jewish population. Therefore, the study of Fanconi anemia can lend insight into the types of cancer-predisposing genetic diseases specific to the Ashkenazi.
Thermal characterization of the plastic crystalline phase

Abstract Differential scanning calorimetry provides a simple and rapid method for the identification and characterization of plastic crystalline materials. The methods used are illustrated by applying them to 2,2-dinitropropane.
Geotechnical issues and answers during construction of the trans-Alaska pipeline

The trans-Alaska oil pipeline completed in 1977 was an unprecedented construction project. Some of the most challenging problems faced were in the geotechnical field. In the format of issues and answers, this paper highlights the activities and decision-making functions of the field engineering organization which was developed. This organization was responsive to the identified need for field confirmation of geotechnical conditions during construction and for assurance of adequacy of as-built construction. Appropriate procedures and line of communication were established to satisfy these needs.
Myotubularin and MTMR2, Phosphatidylinositol 3-Phosphatases Mutated in Myotubular Myopathy and Type 4B Charcot-Marie-Tooth Disease

Myotubularin is the archetype of a family of highly conserved protein-tyrosine phosphatase-like enzymes. The myotubularin gene, MTM1, is mutated in the genetic disorder, X-linked myotubular myopathy. We and others have previously shown that myotubularin utilizes the lipid second messenger, phosphatidylinositol 3-phosphate (PI(3)P), as a physiologic substrate. We demonstrate here that the myotubularin-related protein MTMR2, which is mutated in the neurodegenerative disorder, type 4B Charcot-Marie-Tooth disease, is also highly specific for PI(3)P as a substrate. Furthermore, the MTM-related phosphatases MTMR1, MTMR3, and MTMR6 also dephosphorylate PI(3)P, suggesting that activity toward this substrate is common to all myotubularin family enzymes. A direct comparison of the lipid phosphatase activities of recombinant myotubularin and MTMR2 demonstrates that their enzymatic properties are indistinguishable, indicating that the lack of functional redundancy between these proteins is likely to be due to factors other than the utilization of different physiologic substrates. To this end, we have analyzed myotubularin and MTMR2 transcripts during induced differentiation of cultured murine C2C12 myoblasts and find that their expression is divergently regulated. In addition, myotubularin and MTMR2 enhanced green fluorescent protein fusion proteins exhibit overlapping but distinct patterns of subcellular localization. Finally, we provide evidence that myotubularin, but not MTMR2, can modulate the levels of endosomal PI(3)P. From these data, we conclude that the developmental expression and subcellular localization of myotubularin and MTMR2 are differentially regulated, resulting in their utilization of specific cellular pools of PI(3)P.
The effect of the Earth's magnetic field on measurements of the Doppler Shift of satellite radio transmissions

Effect of the earths magnetic field on measurements of the doppler shift of satellite radio transmissions
Deficiency of copper can cause neuronal degeneration.

Abstract The aim of this article is to emphasize the important role that copper plays in the function of nerve cells. We are reporting preliminary data which suggest that the swelling of axons which we produce in rats by iminodipropionitrile, IDPN, is due to its chelating action on copper, and how conversely supplementation with copper abolishes both symptoms and lesions. The copper values we obtained by atomic absorption spectrophotometry of the spinal cord and brain from the animals fully support this contention. In comparing these results with the diseases that are known to be due to copper deficiency, namely Menkes disease in man, swayback in lambs and several neurological mutant mice, we find not only similar axonal swellings, but also amelioration of symptoms and lesions by early administration of copper. Considering the main forms in which copper is present, we discuss the cuproproteins, i.e. ceruloplasmin and metallothionein, and their role in transport and delivery of copper to various organs. Further, the many cuproenzymes i.e. superoxide dismutase, tryptophan-2,3-dioxygenase, lysine oxidase, cytochrome oxidase, monoamine oxidases, tyrosinase, dopamine-β-hydroxylase and d-amino levulinate dehydratase are noted for their roles in the nervous system. Finally, we suggest that neuronal copper deficiency should be more fully investigated as a possible etiological factor in the more common neurodegenerative diseases, such as Alzheimer's disease and amyotrophic lateral sclerosis, ALS.
Linguistic Structure and Speech Shadowing at Very Short Latencies

SPEECH shadowing is an experimental task in which the subject is required to repeat (shadow) speech as he hears it. When the shadower is presented with a sentence, he will start to repeat it before he has heard all of it. The response latency to each word of a sentence can therefore be measured.
Developmental studies of sea urchin chromatin. Chromatin isolated from spermatozoa of the sea urchin Strongylocentrotus purpuratus.

Abstract Chromatin was isolated from spermatozoa of the sea urchin Strongylocentrotus purpuratus. The isolated chromatin shows less absorptivity ratio of 230 nm : 260 nm and possesses less protein than does embryonic chromatin. The ratio of histone : DNA is 1.02; nonhistone : DNA 0.13; RNA : DNA 0.04. Sperm chromatin melts in two steps with Tms 70°C and 84°C in 2.5 × 10−4, M EDTA in contrast to embryonic chromatin with a single Tm = 72°C. Disc electrophoresis of basic proteins of sperm revealed one minor component with extremely fast mobility and three major components. The one with the slowest mobility is characteristic of sperm. The embryo has in turn its characteristic histone which also migrated slowly in disc electrophoresis. Both of these unique histone fractions are selectively extracted from chromatin by 5% perchloric acid. Amino acid analyses of these chromatographically purified unique fractions show that both contain a large amount of lysine, while that from sperm, in addition, contains also a large amount of arginine. Minimal molecular weights of 33,000 for sperm and 16,200 for embryo unique histone were estimated from these analyses. Sperm chromatin supports a level of RNA synthesis in vitro with exogeneously supplied RNA polymerase about 2% that of the corresponding free DNA.
Investigation of the SV40 - human cancer association: Look for the full signature of the virus

In the controversy about the association of simian virus 40 with human cancers, the greatest problem is the ascertainment of SV40 exposure. This difficulty would be resolved if one were to look for all components of SV40 infection. How does SV 40 circulate in the human community? Do cancer patients with SV40-positive tumors have serological correlates of SV 40 infection and of SV40-induced cancer? SV40 association with a cancer should be studied in the context of the known risk factors for that cancer. The tumor cell-virus relationship should be characterized with respect to viral integration and viral localization to the tumor cell. Specimens should be masked and the assays should include panels of specimens to estimate analytic sensitivity and specificity. In view of the rarity of some of the tumors reported to be associated with SV40, a multi-institutional investigation initiated and coordinated by the NIH would be most effective.
Type Curves for Analysis of Afterflow-Dominated Gas-Well Buildup Data

This paper extends the ''McKinley method'' of type-curve analysis for afterflow-dominated data to gas wells by including the effects of changing gas properties with pressure. While many approximations are involved, it is demonstrated that for gas wells the new curves offer an improvement over McKinley's constant fluid-property curves. It should be possible to use the new curves to obtain a reliable value for near-wellbore permeability and improve estimates of formation permeability and flow efficiency from afterflow-distorted gas-well buildup data.
Deposition of foulant particles during tangential flow filtration

Abstract The fraction of foulant particles deposited on Anopore aluminum oxide microfiltration membranes during tangential flow filtration was measured by direct visual observation (DVO). Yeast cells and 4.5 μm, 10 μm, and 20 μm latex particles were used as model foulants. The fractional particle deposition was found to increase with increasing permeate flux and decrease with increasing wall shear rate. At a fixed permeate flux and wall shear rate, the fractional deposition decreased with increasing particle size, allowing for particle segregation by size. For feed suspensions at the isoelectric point of the membrane (pH 8), individual particles and cells were frequently observed rolling over the membrane surface. To better understand the observed fractional deposition and foulant rolling speed, a mathematical model of a sphere rolling over a rough, permeable surface due to viscous shear flow was developed. The primary parameter in the model is the dimensionless permeate flux, defined as the ratio of permeate flux (velocity of fluid flowing normal to the surface) to the characteristic shear velocity (velocity of fluid flowing tangentially over the surface at one particle radius above the surface). For a given permeate flux, a sphere will stick to the surface only when it encounters a roughness element taller than a critical height. The time-averaged translational velocities of particles rolling over the membrane surface were also calculated using the model and are in good agreement with experimental results, with values reduced by interactions with the membrane to typically 20–50% of the undisturbed tangential fluid velocity at one radius above the membrane.
Structure and genome organization of the large RNA of iris yellow spot virus (genus Tospovirus, family Bunyaviridae)

The structure and organization of the large (L) RNA of iris yellow spot virus (IYSV) was determined, and with this report, the complete genomic sequence of IYSV of the genus Tospovirus, family Bunyaviridae has been elucidated. The L RNA of IYSV was 8,880 nucleotides in length and contained a single open reading frame in the viral complementary (vc) strand. The primary translation product of 331.17 kDa shared many of the features of the viral RNA-dependent RNA polymerase (RdRp) coded by L RNAs of known tospoviruses. The 5′ and 3′ termini of IYSV L RNA (vc) contain two untranslated regions of 33 and 226 nucleotides, respectively, and both termini have conserved terminal nucleotides, another common feature of tospovirus genomic RNAs. Conserved motifs characteristic of RdRps of members of the family Bunyaviridae were present in the IYSV RdRp.
PUTNAM, KANT, AND SECONDARY QUALITIES

L'A. rejette l'affirmation de H. Putnam qui attribue a Kant la these selon laquelle toutes les qualites sont des qualites secondes. Definissant les qualites comme des proprietes 1) dependantes de l'esprit, 2) relationnelles, 3) dispositionnelles, ou 4) des modes de l'espace et du temps, l'A. montre que pour Kant les proprietes des corps sont premieres, alors que les proprietes internes des objets sont secondes
The Impact of Analysts' Forecast Errors and Forecast Revisions on Stock Prices

: We present a comprehensive analysis of the association between stock returns, quarterly earnings forecast errors, and quarter-ahead and year-ahead earnings forecast revisions. We find that forecast errors and the two forecast revisions have significant effects on stock prices, indicating each conveys information content. Findings also show that the fourth quarter differs from other quarters—the relative importance of the forecast error (quarter-ahead forecast revision) is lower (higher). We also find a marked upward shift over time in the forecast error and forecast revision coefficients, consistent with the I/B/E/S database reflecting an improved quality of both earnings forecasts and actual earnings.
The F2 Excretion of Normal Men on Different Levels of Niacin Intake.

SummaryF2 analyses have been made on the urine of normal young men who were maintained on controlled niacin intakes. The method of Najjar showed no difference in the F2 excretion of 2 groups whose intakes over a period of 161 days averaged 12.4 and 22.4 mg of niacin per day. There was no difference in the F2 excretion of 2 groups maintained for 32 days on intakes of 0.12 and 10.12 mg of niacin per day when the method of Huff and Perlzweig was used for the determination.
The influence of strains on retained vacancy supersaturations in rapidly cooled metals

We have calculated the stresses that are customarily encountered in the rapid quenching of small specimens of high thermal diffusivity. Stresses due to both thermal gradients and hydrodynamic drag were considered. The effect of plastic strains on retained thermal vacancy concentrations was evaluated by quenching pure platinum wires while simultaneously deforming them. The smallest plastic shear strains imposed were less than 10−5 and the largest greater than 10−2. In this range, increasing the strain invariably reduced the concentration of retained vacancies. The fractional vacancy loss increased with increasing quench temperature. The evidence indicates that quenching strains normally encountered are of little consequence. The dominant result of large plastic strains is more sinks for vacancies rather than more vacancies.
Investigation of the magnitude and range of the Ruderman-Kittel interaction in SmRh4B4 and ErRh4B4.

The superconductive and magnetic transition temperatures taken together are shown to provide a unique probe which separately determines both the magnitude and range of the Ruderman-Kittel interaction in the $R{\mathrm{Rh}}_{4}{\mathrm{B}}_{4}$ magnetic superconductors ($R=\mathrm{E}\mathrm{r},\phantom{\rule{0ex}{0ex}}\mathrm{S}\mathrm{m}$). Experimentally, an unexpected peak is found in the antiferromagnetic-ordering temperature of Sm${\mathrm{Rh}}_{4}$${\mathrm{B}}_{4}$ versus electron mean free path, while for Er${\mathrm{Rh}}_{4}$${\mathrm{B}}_{4}$ the ferromagnetic-ordering temperature decreases monotonically. These qualitative features, as well as the quantitative differences between Sm${\mathrm{Rh}}_{4}$${\mathrm{B}}_{4}$ and Er${\mathrm{Rh}}_{4}$${\mathrm{B}}_{4}$, are in excellent agreement with calculations using a mean-free-path-dependent Ruderman-Kittel interaction.
Secure Compressed Domain Watermarking for H.264 Video

Exponential growth of the internet provided new ways of propagating and sharing digital video data. Thus ownership protection of the video data is critical and important in this era. Though there are many standards and technologies available to efficiently share the digital video, almost all of them lack ownership protection mechanism. This paper proposes new compressed domain secure digital watermarking algorithm for H.264 video. Our algorithm selects the macroblocks in a pseudo random sequence based on a secret key and based on the content of the macro-block. The proposed algorithm is of low complexity and suitable to embed watermark in real time along with H.264 video encoding.
Relationships of a brief measure of youth assets to health-promoting and risk behaviors.

Abstract Purpose To test the utility of a brief measure of developmental assets for predicting risk and health-promoting behaviors. Methods Six "assets" questions were added to an existing school-based survey of health-related behaviors. "Asset" questions dealt with students' grades in school, their communication with parents about school, students' perceptions of their role in school decision-making, students' participation in after-school activities and volunteering, and students' perceptions that they "matter" in their community. Participants were 30,916 Vermont students in grades 8–12. The sample included approximately equal numbers of girls and boys. It was 92% white. Fifty-nine percent of students' mothers had completed at least some postsecondary education (according to student report). Data were analyzed by Chi-square techniques and logistic regression. Results Number of assets (0–6) was negatively related to students' engagement in each of seven risk behaviors, and positively related to three health-promoting behaviors. The effects of number of assets were in most cases independent of demographic variables. Among the six assets, academic success (grades in school) contributed the greatest effect for most of the outcome measures; however, each of the assets contributed significant independent effects to multiple risk- and health-behaviors. Conclusions Students' assets, even if relatively few, may make important contributions to wellness, independent of other well-established demographic factors.
Evidence for two catalytically independent clusters of active sites in a functional modular polyketide synthase.

Modular polyketide synthases (PKSs), such as the 6-deoxyerythronolide B synthase (DEBS), catalyze the biosynthesis of structurally complex and medicinally important natural products. These large multifunctional enzymes are organized into “modules”, where each module contains active sites homologous to those of higher eucaryotic fatty acid synthases (FASs). Like FASs, modular PKSs are known to be dimers. Here we provide functional evidence for the existence of two catalytically independent clusters of active sites within a modular PKS. In three bimodular derivatives of DEBS, the ketosynthase domain of module 1 (KS-1) or module 2 (KS-2) or the acyl carrier protein domain of module 2 (ACP-2) was inactivated via site-directed mutagenesis. As expected, the purified proteins were unable to catalyze polyketide synthesis (although the KS-1 mutant could convert a diketide thioester into the predicted triketide lactone). Remarkably however, the KS-1/KS-2 and the KS-2/ACP-2 mutant pairs could efficiently complement ...
Studies of onion root respiration. V. Effect of culturing temperature and seed sample on root respiration and diameter.

Abstract Onion roots from two differents “lots” of sets were grown in nutrient solution at three different temperatures; 20, 25, and 30°C. Gas exchange measurements (in air and O2) were made at 30°C on 0–5, 0–10, and 0–15 mm segments of the root using the Warburg manometic technique; values for the 5–10 and 10–15 mm segments were for the most part obtained by difference, however, some few measurements were made directly. Roots cultured at the higher temperatures show a decrease in rate of oxygen consumption and carbon dioxide production as compared to those cultured at 20°C. This decrease is not proportional in the case of the two gases exchanged as exemplified by the fact that the respiratory quotient exhibits a decreased value for the roots cultured at the higher temperatures. This indicates that carbon dioxide production is depressed to a greater degree than is oxygen consumption. The most marked changes of his nature are shown by meristematic tissue. The diameter of the roots produced at the three temperatures is not significantly different for any one “lot” of onion sets. However, the diameter of roots produced from different “lots” of sets is markedly different. Because of this, the desirability of reporting measurements of gas exchange per unit weigtht of tissue rather than per root is shown; a practice which should result in more comparable data. Also, in any one series of investigations, it appears to be desirable to use onion sets from the same “lot”. The results are discussed in relation to earlier investigations. It is suggested that onion roots, as well as other plant tissue, be cultured at constant temperature, which should yield more reproducible results in future experimental work.
Neck MR Imaging Anatomy

The normal MR imaging appearance of the neck can be confusing given the number and complexity of structures that pass through it. This article strives to simplify normal MR imaging anatomy of the neck using a spatial approach. We present the protocols used at our institution and provide tables with details. Magnetic resonance (MR) imaging anatomy and appearance of the deep spaces of the neck are described with extensive labeled imaging correlates. Pearls and common pitfalls encountered with MR imaging of the neck are discussed. Additional aspects of normal neck MR imaging are described including lymph node, brachial plexus, and vascular anatomy.
Molecular determinants of neural crest migration

Normal septation of the cardiac outflow tract requires migration of neural crest cells from the posterior rhombencephalon to the branchial arches and developing conotruncal endocardial cushions. Proper migration of these cells is mediated by a variety of molecular cues. Adhesion molecules, such as integrins, are involved in the interaction of neural crest cells with the extracellular matrix, while cadherins allow neural crest cells to interact with each other during their migration. Pax3 appears to be important for proliferation of neural crest precursors, and connexin-43-mediated gap junction communication influences the rate of migration. Endothelin and its receptors are required for normal postmigratory differentiation. Platelet-derived growth factor and retinoic acid have roles in neural crest migration and differentiation as well. Finally, the similarity between the cardiovascular malformations seen in the DiGeorge and 22q11 deletion syndromes and animal models of neural crest deficiency has led to the examination of the role of genes located near or within the DiGeorge critical region in neural crest migration. Am. J. Med. Genet. (Semin. Med. Genet.) 97:280–288, 2000. © 2001 Wiley-Liss, Inc.
New design for anterior unit-built porcelain prostheses.

Abstract The disadvantages of breakage, gingival impingement, and poor esthetic contour associated with a unit-built porcelain prosthesis have been eliminated by employing a new design of the substructure frame. The substructure frame has been strengthened by the addition of a high lingual shoulder to prevent flexing of the metal and subsequent porcelain fracture. The solder joints have been relocated incisally, thus maintaining proximal space for greater gingival health. Also, the incisal location of the solder joint makes it possible to taper the proximal surfaces of the porcelain jackets toward the gingivae. This eliminates the proximal bulk which, previously, was necessary to hide the gingival solder joint and facilitates the fabrication of a porcelain unit-built restoration that not only encourages gingival health but is esthetic and lifelike as well. A new full-coverage preparation and a technique that facilitates two thirds reduction in the size of the labial gold collar have been suggested. The new substructure coping design also can be employed when a complete porcelain-fused-to-metal prosthesis is desired.
Generalization of the Child Observation Record: a validity study for diverse samples of urban, low-income preschool children

The present investigation addressed the construct validity of the Child Observation Record (COR) with low-income urban preschool children. From two separate samples representing low-income preschool children, COR ratings were analyzed using multivariate techniques. Independent analyses from these two urban sites yielded a three-dimensional structure: Cognitive Skills, Social Engagement, and Coordinated Movement. Further analyses cross-validated this structure for males and females and across ethnic groups. Concurrent assessments provided convergent and discriminant validity for the Social Engagement dimension and convergent validity for Cognitive Skills dimension. Analyses of item distributions of the 5-point developmental sequences represented by the 30 COR items were used to examine the assumption that all the distributions were continuous unimodal distributions. Findings did not universally support this assumption revealing some irregular distributions with troughs in the mid-range of continua. Implications of the findings for early childhood assessment of vulnerable children and future research were discussed.
Synthesis and structure of Ag(1-Me-12-SiPh3-CB11F10): selective F12 substitution in 1-Me-CB11F11- and the first Ag(arene)4+ tetrahedron.

The selective substitution of the antipodal F atom in 1-Me-CB11F11- with a SiPh3 moiety led to the isolation and structure determination of the cesium(I) and silver(I) salts of the 1-Me-12-SiPh3-CB11F10- anion. The silver salt contains both a nearly trigonal-planar Ag(arene)3+ cation and the first example of a Ag(arene)4+ cation.
Operant behavior in transition: FI to FI

Three rats received extensive initial training on an FI 2-min schedule of reinforcement and were then shifted to an FI 30-sec schedule. The length of the postreinforcement pause very rapidly decreased, suggesting that the rats were “surprised” by the changed schedule. The subsequent shift back to the FI 2-min schedule led to a gradual change in performance, with responding appropriate to both intervals occurring.
Ocular drug delivery

Drug delivery to the eye is hampered by anatomical factors, including the corneal epithelium, the blood-aqueous barrier and the blood-retinal barrier. This review aims to outline the major routes of ocular drug delivery, including systemic, topical, periocular and intravitreal. The pharmacokinetics, the disadvantages and the clinical relevance of these drug delivery routes have been emphasised. Recent advances in surgical techniques, therapeutic approaches and material sciences have produced exciting new therapies for ocular diseases. The role of ophthalmic drug formulation in targeting the desired ocular tissue and enhancing drug delivery by the chosen route whilst minimising side effects is also discussed.
The ambivalent, knowing male body in the Pasadena dance theatre

Classical ballet training, in the context of a semi‐professional company, serves as an initiatory vehicle for its male participants. This study examines the negotiation of this initiatory vehicle by men in the Pasadena Dance Theatre (PDT), a highly acclaimed company in Pasadena, California. Examined are the ways in which the PDT men consolidate cohesive group subject positions; how difference is framed and policed; how masculine agency is bracketed and qualified; and how the masculine ballet dancer as subject position is mediated through/by the women's bodies which set masculinity in motion.
Discrete Internal Symmetry Groups for Leptons and Quarks

The successful identification of the internal symmetry groups for the leptons and quarks can be verified by obtaining the correct values for a host of invariant quantities including the rest masses of the particles. It appears that three related discrete rotation groups are viable contenders for the three lepton families, one group for each family. The model predicts no more leptons to be discovered. An extension to the quarks predicts four quark families.
A fast algorithm for 3D reconstruction from unoriented projections and cryo electron microscopy of viruses

In a cryo electron microscopy experiment, the data is noisy 2-D projection images of the 3-D electron scattering intensity where the orientation of the projections is not known. In previous work we have developed a solution for this problem based on a maximum likelihood estimator that is computed by an expectation maximization algorithm. In the expectation maximization algorithm the expensive step is the expectation which requires numerical evaluation of 3- or 5-dimensional integrations of a square matrix of dimension equal to the number of Fourier series coeffcients used to describe the 3-D reconstruction. By taking advantage of the rotational properties of spherical harmonics, we can reduce the integrations of a matrix to integrations of a scalar. The key properties is that a rotated spherical harmonic can be expressed as a linear combination of the other harmonics of the same order and that the weights in the linear combination factor so that each of the three factors is a function of only one of the Euler angles describing the orientation of the projection.