cssi/SciSciGPT-SciSciNet huggingface dataset:
Sorption of iodine on minerals investigated by X-ray absorption near edge structure (XANES) and 125I tracer sorption experiments

The sorption of I on a set of selected minerals was examined by: X-ray absorption near edge structure (XANES) and high concentration chemical sorption experiments, as well as very low concentration tracer (using 125I) sorption experiments. A XANES method was used to determine I2, I(V) and I (-I) in supernatant solutions and slurries of minerals. This is, we believe, the first reported use of XANES to investigate the redox state of I that is sorbed on minerals. With this technique, it was determined that pyrite, biotite and magnetite sorb I from solutions containing 1000 μg ml−1 I. In the pyrite/water system, IO3− was reduced to what appeared to be I2 in the XANES scans and sorbed on the minerals surface. Magnetite sorbed I− from solution but not IO3−. In contrast, biotite sorbed IO3− from solution but did not take up any I−. No changes in I redox state were observed in the magnetite and biotite experiments. Based on this association the presence of Fe(II) in the sorbing phase appears to be related to uptake, but not necessarily to a change in I redox. Results of the XANES experiments, in which high concentrations of 1 were used, were corroborated for IO3− with pyrite, magnetite and biotite at very low concentrations of 125I. Most of the other minerals tested sorbed small fractions of the 125I tracer, but this level of uptake could not be observed in XANES scans. To examine the relationship between pyrite and IO3−, experiments were conducted in which concentrations of Fe, I, S2− and SO42− were determined in the aqueous phase of slurries containing pyrite. In the presence of I (starting as IO3−), concentrations of Fe in solution were significantly lower than without I, even at pH values sufficiently low that Fe should stay in solution. The XANES spectra indicate that I2 is present on this material, eliminating the possibility of FeI2 formation where I is present as I−. The implication is that I2, sorbed on the surface, inhibits release of Fe to solution (or promotes its precipitation) while S is oxidized to SO42− and released.
The role of T cell receptor signaling thresholds in guiding T cell fate decisions

Canonical T cell receptor signal transduction has been extensively studied and dissected in cell lines and primary lymphocytes. However, a static depiction of this signaling cascade fails to capture the complex and dynamic process by which individual T cells discriminate TCR:peptide-MHC affinity, then integrate signals over time to drive discrete cellular behaviors such as thymic selection, proliferation, and cytokine production. Recent technological advances have made it possible to study complex lymphocyte behavior on a single cell level and are revealing how T cells interpret information about affinity and abundance of antigen in order to make life-and-death cell fate decisions individually and collectively.
Agreement between indirect measures of perceived distance

A test configuration consisting of either one or two points of light was made to appear at different distances on different trials. The perceived distance of the configuration on each trial was measured indirectly using two procedures. In the size adjustment procedure, the observer adjusted the vertical separation of two equidistant points to produce a criterion-perceived separation of 1 in. On the basis of this adjustment, the perceived distance of the two-point configuration was derived by means of the size-distance invariance hypothesis (Gilinsky, 1951; Kilpatrick & Ittelson, 1953). In the head-motion procedure, the observer indicated the motion of a physically stationary test point as it appeared to move concomitantly with the head. On the basis of the direction and magnitude of this apparent motion, the perceived distance of the test point was derived by means of the apparent-distance/pivot-distance hypothesis (Gogel, 1982).The measures obtained from these two procedures correlated highly. Since the size adjustment procedure provides a measure of perceived distance that generally is accepted as valid, the results indicate that the head-motion procedure has a similar validity. Past research with the head-motion procedure often concerned the apparent motion or apparent distance of a single object presented in a dark surround. An analysis of the present results supports the conclusion that the apparent-distance/ pivot-distance hypothesis applies equally to situations in which objects in addition to the test object are present.
A Comparison of Early Childhood and Elementary Education Students' Beliefs about Primary Classroom Teaching Practices.

Abstract Two professional preparation paths lead to teaching positions in the lower primary grades; their different histories and emphasis result in potentially conflicting paradigms. We examined the viewpoints of 119 pre-service teachers who were either at the beginning or near the end of their programs in early childhood (ECED) or elementary education (ELED). They completed a survey of their beliefs about primary classroom practices. ECED students, compared to ELED students, favored practices more consistent with the constructivist nature of National Association for the Education of Young Children (NAEYC) guidelines in several areas, including teaching strategies, expectations of the children, assessment strategies, and teacher- and child-directed activities. One significant difference was found between beginning students and student teachers, with student teachers favoring more frequent use of less developmentally appropriate behavior management strategies.
Critical Dynamics of Ferromagnets in 6 − ε Dimensions

The critical dynamics of a model isotropic ferromagnet is studied in $6\ensuremath{-}\ensuremath{\epsilon}$ dimensions both above and below ${T}_{c}$. The renormalization group and the characteristic frequency exponent $z$ are determined to order $\ensuremath{\epsilon}$. Implications of the renormalization group are discussed. A direct calculation of the dynamic response function to order $\ensuremath{\epsilon}$ shows many interesting features, especially for $Tl{T}_{c}$.
Membrane isolation on polylysine-coated glass beads. Asymmetry of bound membrane

Erythrocyte membranes isolated on polylysine-coated glass beads exhibit many of the properties of the native membrane. Gel electrophoresis indicates that all major protein components of the membrane are retained during membrane isolation. The membrane integrity and accessibility of selected components was tested using non-penetrating probes. In general, membranes on beads displayed accessibility properties typical of inside-out vesicles. The accessibility of membrane acetylcholinesterase to assay reagents, as well as membrane accessibility to the actions of neuraminidase, trypsin and galactose oxidase-NaB3H4 demonstrated that the protoplasmic surface of membrane isolated on beads was exposed, while the extracellular surface was inaccessible. The differential accessibility of the membrane surfaces demonstrates the feasibility of investigating asymmetry of membranes isolated on cationic glass beads.
New concepts in collectin-mediated host defense at the air-liquid interface of the lung.

Objectives: Surfactant proteins A (SP-A) and D are collectins that play key roles in innate immune defense of the lung. Recent studies suggest that these proteins have a direct effect on the growth and viability of Gram-negative bacteria, Mycoplasma pneumoniae and Histoplasma capsulatum. Methodology: The researchers examined membrane permeabilization by BAL fluid of mice that were sufficient or deficient in surfactant proteins, of rough and smooth LPS-containing membranes, and of genetically altered bacteria. The permeability assay is based on the ability of agents to promote access of impermeable dyes propidium iodide and ELF97 to intracellular targets. Results: The permeabilizing activity of concentrated BAL material from SP-A+/+ mice was substantially greater than that from SP-A–/– animals, and was sensitive to hyperoxic exposure. Oxidation of the collectins in vitro also blocked their antimicrobial effects. Rough but not smooth LPS conferred susceptibility of model bacterial membranes to permeabilization by the collectins. The screening of genetically engineered SP-A mice with a Pseudomonas aeruginosa signature tagged mutagenesis library has revealed several pathways which are required for resistance to the permeabilizing effects of SP-A, including those required for salicylate biosynthesis and flagellar function. Conclusion: The researchers conclude that the pulmonary collectins directly permeabilize bacteria in an LPS-dependent and rough LPS-specific manner. Oxidative damage blocks the permeabilizing activity of alveolar lining fluid and purified proteins. The mechanism(s) of permeabilization is not known, but the crystal structure of SP-A reveals a hydrophobic cleft lined by charged residues which may play a role in membrane perturbation.
Utilizing UV and visible sensors on micro satellites to demonstrate target acquisition and tracking

The Distributed Sensing Experiment (DSE) program is a technology demonstration of target acquisition, tracking, and three-dimensional track development using a constellation of three micro satellites. DSE will demonstrate how micro satellites, working singly and as a group, can observe test-missile boost and ballistic-flight events. The overarching program objective is to demonstrate a means of fusing measurements from multiple sensors into a composite track. To perform this demonstration, each DSE micro satellite will acquire and track a target, determine a two-dimensional direction and movement rate for each, communicate observations to other DSE satellites, determine a three-dimensional target position and velocity, and relay this information to ground systems. A key design parameter of the program is incorporating commercial off-the-shelf (COTS) hardware and software to reduce risk and control costs, while maintaining performance. Having completed a successful Critical Design Review, the program is currently in fabrication, integration, and test phase. The constellation of satellites is scheduled for launch in CY2009. This paper describes the status and capabilities of the UV and visible sensor payloads, as well as the algorithms and software being developed to achieve the DSE mission.
Some Factors Affecting the Sensitivity and Spectral Response of Thermoelectric (Radiometric) Detectors

A number of thermal detectors (thermopiles) has been studied for variations in sensitivity which exist over their surfaces and also for variations of sensitivity with wavelength. These variations differ depending upon whether the thermoelectric output is measured with dc instrumentation, with conventional ac instrumentation, or with ac synchronous rectifier instrumentation. In general, lower responses for the longer wavelengths are observed when commercial thermopiles are compared with a new cavity black-body detector—and the difference may be greater when measured with ac synchronous rectifier instrumentation. When the output of a detector is measured through the use of a conventional tuned ac amplifier, variation in sensitivity of as much as 5 to 1 has been found for different areas of the surface. When a phase-sensitive amplifier is employed, first set for maximum response with the entire thermopile irradiated, even larger variations in sensitivity may be observed.
Shotgun Proteomics of the Haloarchaeon Haloferax volcanii

Haloferax volcanii, an extreme halophile originally isolated from the Dead Sea, is used worldwide as a model organism for furthering our understanding of archaeal cell physiology. In this study, a combination of approaches was used to identify a total of 1296 proteins, representing 32% of the theoretical proteome of this haloarchaeon. This included separation of (phospho)proteins/peptides by 2-dimensional gel electrophoresis (2-D), immobilized metal affinity chromatography (IMAC), metal oxide affinity chromatography (MOAC), and Multidimensional Protein Identification Technology (MudPIT) including strong cation exchange (SCX) chromatography coupled with reversed phase (RP) HPLC. Proteins were identified by tandem mass spectrometry (MS/MS) using nanoelectrospray ionization hybrid quadrupole time-of-flight (QSTAR XL Hybrid LC/MS/MS System) and quadrupole ion trap (Thermo LCQ Deca). Results indicate that a SCX RP HPLC fractionation coupled with MS/MS provides the best high-throughput workflow for overall prot...
Photoionization of N-Alkylphenothiazines in Mesoporous SiMCM-41, AlMCM-41, and TiMCM-41 Molecular Sieves

Electron spin resonance and diffuse reflectance spectroscopy have been used to monitor the photoionization yields of N-alkylphenothiazine cation radicals (PC{sub n}{sup +}) generated by UV irradiation within mesoporous SiMCM-41, AlMCM-41, and TiMCM-41 molecular sieves. Mesoporous SiMCM-41 and AlMCM-41 molecular sieves are efficient for accomplishing stable photoproduced electron transfer of N-alkylphenothiazine molecules (PC{sub n}) at room temperature and at 77 K. A series of mesoporous TiMCM-41 molecular sieves with variable amounts of framework titanium have been hydrothermally synthesized and used for PC{sub n} photoionization in comparison with SiMCM-41 and AlMCM-41 molecular sieves. The addition of Ti into the framework of SiMCM-41 increases the net PC{sub n}{sup +} cation radical photoyield at room temperature and 77 K. Thus, Ti in the TiMCM-41 framework is suggested to act as a better electron acceptor in competition with SiMCM-41 and AlMCM-41 molecular sieves. The photoionization efficiency for form PC{sub n}{sup +} cation radicals increases in the order SiMCM-41 < AlMCM-41 < TiMCM-41. The photooxidation yields decrease as the alkyl chain lengths of the PC{sub n} molecules increase from methylphenothiazine (PC{sub 1}) to hexadecylphenothiazine (PC{sub 16}). Diffuse reflectance (DR) UV-visible spectra support the formation of some radical cation dimer as the alkyl chain length increases frommore » PC{sub 1} to PC{sub 16} in all MCM-41 materials and thus the photoionization yields decrease from PC{sub 1} to PC{sub 16}. The photoyield is higher by about 2.5 times at 77 K compared to room temperature. The PC{sub n}{sup +} cation radicals are stable in SiMCM-41, AlMCM-41, and TiMCM-41 at room temperature for several hours and do not decay at 77 K. The observed photoyields of PC{sub n} molecules in mesoporous MCM-41 molecular sieves suggest that these materials can be utilized effectively for solar energy conversion and storage.« less
Prototyping with microsoft .net gadgeteer

Microsoft .NET Gadgeteer is a new prototyping platform that makes it easier to construct, program and shape new kinds of computing objects. It is comprised of modular hardware, software libraries and 3D CAD support. Together, these elements support the key activities involved both in the rapid prototyping and the small-scale production of custom embedded, interactive and connected devices. We propose to organize and run a studio at TEI 2010 where participants are introduced to the platform and its capabilities. Participants will work in groups, assembling electronic modules, writing software and designing a case or enclosure for their device. The end-result will be that each group develops a fully functional device, which can be exhibited at the TEI demo session.
Biofilm Growth and Detachment of Actinobacillus actinomycetemcomitans

The gram-negative, oral bacterium Actinobacillus actinomycetemcomitans has been implicated as the causative agent of several forms of periodontal disease in humans. When cultured in broth, fresh clinical isolates of A. actinomycetemcomitans form tenacious biofilms on surfaces such as glass, plastic, and saliva-coated hydroxyapatite, a property that probably plays an important role in the ability of this bacterium to colonize the oral cavity and cause disease. We examined the morphology of A. actinomycetemcomitans biofilm colonies grown on glass slides and in polystyrene petri dishes by using light microscopy and scanning and transmission electron microscopy. We found that A. actinomycetemcomitans developed asymmetric, lobed biofilm colonies that displayed complex architectural features, including a layer of densely packed cells on the outside of the colony and nonaggregated cells and large, transparent cavities on the inside of the colony. Mature biofilm colonies released single cells or small clusters of cells into the medium. These released cells adhered to the surface of the culture vessel and formed new colonies, enabling the biofilm to spread. We isolated three transposon insertion mutants which produced biofilm colonies that lacked internal, nonaggregated cells and were unable to release cells into the medium. All three transposon insertions mapped to genes required for the synthesis of the O polysaccharide (O-PS) component of lipopolysaccharide. Plasmids carrying the complementary wild-type genes restored the ability of mutant strains to synthesize O-PS and release cells into the medium. Our findings suggest that A. actinomycetemcomitans biofilm growth and detachment are discrete processes and that biofilm cell detachment evidently involves the formation of nonaggregated cells inside the biofilm colony that are destined for release from the colony.
Individual differences in stroop and local-global processing: a possible role of interhemispheric interaction.

Two experiments are reported examining individual differences in the processing of centrally presented stimuli containing two dimensions of information lateralized to opposite cerebral hemispheres. Left-handers, arising from (a) their lesser degree of functional lateralization and (b) their greater degree of callosal connectivity, were hypothesized to exhibit greater interdimensional (and presumably interhemispheric) interaction. Experiment 1 utilized local-global stimuli, and left-handers were found to be impaired at keeping the two dimensions independent and superior at integrating the two dimensions. Experiment 2 used Stroop stimuli, and left-handers again were impaired at keeping the two dimensions independent (i.e., showed greater Stroop interference). Correlational analyses indicated that the mechanisms of interdimensional integration versus independence are at least partially independent from one another. Results suggest that aspects of interhemispheric interaction can be addressed via the use of nonlateralized input.
Source of Solar Acoustic Modes

Solar acoustic modes are found to be excited in a thin superadiabatic layer of turbulent convection (about 75±50 km below the photosphere) beneath the Sun's surface. Comparing the theoretical power spectra of both velocity and pressure oscillations of medium angular degree with that obtained from the Michelson Doppler Imager instrument on board the Solar and Heliospheric Observatory, we find that a composite source consisting of a monopole, which corresponds to mass or entropy fluctuations, and a quadrupole, which consists of the Reynolds stress, excites these oscillations. The dominant source is of a monopole type since it provides the best match to the observed velocity and intensity oscillation power spectra. For the above source to match the observed asymmetry in intensity, a part of the background is found to be correlated with the pressure perturbation. The sign of the correlation is found to be negative, which suggests that there is photospheric darkening prior to the occurrence of the localized acoustic event, in agreement with the previous finding of P. R. Goode and coworkers.
Formation of [Des-Asp1]angiotensin I by the perfused rat lung.

Bioassay studies have indicated that angiotensin I (Ang I), but not angiotensin II (Ang II), is degraded by the intact lung. The present study was an attempt to isolate and quantify pulmonary metabolites of Ang I. The pulmonary vascular bed of the rat was isolated and perfused at 4–6 ml/min (<20 mm Hg) with oxygenated Krebs buffer containing 5% bovine serum albumin. [3H-Leu10]Ang I (3–10 ng) was administered, and pulmonary effluent samples were collected every 15 sec for 5 min. Peptides were isolated by Dowex chromatography and separated by thin layer chromatography.3H-labeled peptides were eluted from the thin layer chromatography plate, and the Ang I and [des-Asp1]Ang I levels were estimated by RIA. These peptides were shown to be hydrolyzed by purified converting enzyme with the release of His-3H-Leu. About 25% of the [3H]Ang I administered was isolated as [3H-des-Asp1]Ang I, and this percentage increased to 33% after treatment with teprotide. These studies clearly demonstrate that [des-Asp1]Ang I is a...
Enabling HPC simulation workflows for complex industrial flow problems

The use of simulation based engineering taking advantage of massively parallel computing methods by industry is limited due to the costs associated with developing and using high performance computing software and systems. To address industries ability to effectively include large-scale parallel simulations in daily production use, two key areas need to be addressed. The first is access to large-scale parallel computing systems that are cost effective to use. The second is support for complete simulation workflow execution on these systems by industrial users. This paper presents an approach, and set of associated software components, that can support industrial users on large-scale parallel computing systems available at various national laboratories, universities, or on clouds.
Modes of Thought and Meaning Making: The Aftermath of Trauma

Although it has been well documented that the key to positive growth in the aftermath of trauma is creating renewed meaning, there is a need for research documenting the specific cognitive processes by which this is accomplished. This article examines the cognition of two high-achieving professionals who are in the midst of restoring meaning to their professional lives following traumatic experiences. Using a case study approach, this article identifies commonalties between both professionals (showing how the use of metaphor, “world making,” and context influence meaning making) and the differences that emerge because of unique life circumstances.
Computer-assisted interpretation of mass spectrometry—mass spectrometry data of potentially hazardous environmental compounds

Abstract Dunn III, W.J. and Swain, D., 1993. Computer-assisted interpretation of mass spectrometry—mass spectrometry data of potentially hazardous environmental compounds. Chemometrics and Intelligent Laboratory Systems , 19: 175–179 The recent development of tandem mass spectrometry (MS), with much higher information content in the mass spectrum, makes it possible to obtain higher identification accuracy compared to that obtained with one-dimensional mass spectra. We have begun a project to explore the use of computational pattern recognition methods to identify compounds from their tandem mass, or MS—MS, spectra. We have obtained MS—MS spectra of several potentially hazardous polycyclic aromatic hydrocarbons and other compounds of environmental interest and applied pattern recognition to these spectra. Some of our recent findings are discussed below.
PHOTOPERIODIC RESPONSE OF LESPEDEZA.

Several attempts have been made to establish various leguminous plants as forage and cover crops on pasture land in Hawaii. Korean Lespedeza (Lespedeza stipulacea Maxim) and the common Lespedeza (L. striata Thunb. H and A) were among those tried. These two species are widely grown throughout the central and southern parts of the United States, where they attain good vegetative growth and are from one to two feet in height. In contrast, when they are grown in Hawaii, these plants attain a height of only a few inches before maturing. Their inability to develop a good vegetative growth in Hawaii suggested that their failure was concerned with the relationship of the plants to the relative length of day. Based on this supposition, a series of experiments was conducted to determine the critical day length for flowering in Lespedeza. Smith (2) reported that Lespedeza can be grown under 14 hours of photoperiod without fruiting. However, the effect of increasing the duration of the light period up to the critical photoperiod for the initiation of flowering has not been investigated. Four light-tight chambers were constructed. The plants were grown in wooden soil boxes 3 ? 4 ? 1.5 ft. in size which were placed on galvanized pipe frames fitted with rollers. The boxes were rolled out of the light-tight chambers each morning at 7:30 a.m., and the plants were exposed to normal conditions of sunlight intensity until 4:30 p.m. The length of the various photoperiods was adjusted by exposing the plants in the chambers to additional light from fluorescent lamps regulated by time switches. In each experiment, the treatments were started as soon as the seeds began to germinate. A field test was conducted during the longer days of the year to corroborate the results obtained in the chambers.
The role of within-compound associations in learning about absent cues

When two cues are reinforced together (in compound), most associative models assume that animals learn an associative network that includes direct cue–outcome associations and a within-compound association. All models of associative learning subscribe to the importance of cue–outcome associations, but most models assume that within-compound associations are irrelevant to each cue’s subsequent behavioral control. In the present article, we present an extension of Van Hamme and Wasserman’s (Learning and Motivation 25:127–151, 1994) model of retrospective revaluation based on learning about absent cues that are retrieved through within-compound associations. The model was compared with a model lacking retrieval through within-compound associations. Simulations showed that within-compound associations are necessary for the model to explain higher-order retrospective revaluation and the observed greater retrospective revaluation after partial reinforcement than after continuous reinforcement alone. These simulations suggest that the associability of an absent stimulus is determined by the extent to which the stimulus is activated through the within-compound association.
Numerical study of water management in the air flow channel of a PEM fuel cell cathode

Abstract The water management in the air flow channel of a proton exchange membrane (PEM) fuel cell cathode is numerically investigated using the FLUENT software package. By enabling the volume of fraction (VOF) model, the air–water two-phase flow can be simulated under different operating conditions. The effects of channel surface hydrophilicity, channel geometry, and air inlet velocity on water behavior, water content inside the channel, and two-phase pressure drop are discussed in detail. The results of the quasi-steady-state simulations show that: (1) the hydrophilicity of reactant flow channel surface is critical for water management in order to facilitate water transport along channel surfaces or edges; (2) hydrophilic surfaces also increase pressure drop due to liquid water spreading; (3) a sharp corner channel design could benefit water management because it facilitates water accumulation and provides paths for water transport along channel surface opposite to gas diffusion layer; (4) the two-phase pressure drop inside the air flow channel increases almost linearly with increasing air inlet velocity.
BI-08MICROVESICLES CAN DISTINGUISH BETWEEN TUMOR PROGRESSION AND TREATMENT EFFECT/PSEUDOPROGRESSION IN GLIOBLASTOMA PATIENTS TREATED WITH RADIATION AND TEMOZOLOMIDE.

The standard of care for glioblastoma (GB) is radiation therapy (RT) and temozolomide (TMZ) following optimal surgery. This regimen has been accompanied by an increase in the occurrence of equivocal imaging findings, e.g. tumor progression vs. treatment effect (TE), which includes pseudoprogression (PsP). Thus decisions regarding further treatment are difficult and often delayed. None of the current imaging methods for identifying TE/PsP have proven sensitive and specific. Therefore, we developed a method to isolate microvesicles (MV) from blood sample in patients with GB. MV are defined herein as lipid membrane-bound sacs with a diameter >300 nm. METHODS: 3 ml citrated blood was collected from GB patients at their RT simulation and at multiple times during and following treatment. MV were isolated during multiple centrifugations (300g, 2500g, 15,000g). The pellet from the final spin was analyzed using flow cytometry. Antibodies to phosphotidylserine were used to identify the MV. RESULTS: We analyzed 16 blood samples from 10 GB patients that met analysis criteria: the MV sample was obtained at or following the completion of CRT and, a definitive diagnosis (TP, TE or PSP) was reached within 60 days of the date of the sample. MV counts in the patients with stable disease or TE/PsP were significantly lower than patients who developed recurrence or died of their disease (p = 0.0385). Based on MRI and/or pathological assessment, 2 patients have died of their disease, 1 patient is alive with recurrence, 3 patients have stable disease and 4 patients are being followed for PsP vs. tumor progression (TP). SUMMARY/CONCLUSION: These preliminary data suggest that the analysis of blood (liquid biopsy) for MV may be useful to distinguish TE/PsP from TP in GB patients. MVs may be valuable in addition to standard imaging for decision making in patients with equivocal imaging findings.
Metabolism of testosterone-4-14C by rat skin: variations during the hair cycle.

The metabolism of testosterone-4-14C by the skin of Wistar rats was followed in three consecutive hair cycles. The major metabolites were Δ4-androstenedione and 5α-dihydrotestosterone; minor products were 5α-androstanedione, 3α-androstanediol, androsterone, epiandrosterone, and 3β-androstanediol. It was observed that the metabolism of testosterone fluctuated during the hair cycles in the hairy skin, but was without significant variations in glabrous skin. The 5α-reductase activity was examined by summing the 14C in the 5α-metabolites. When this activity was expressed in mg of DNA content of skin, an increase was observed in the resting phase of the hair cycle (telogen). The 17β-hydroxysteroid dehydrogenase activity was examined by summing the 14C in the 17-ketometabolites, and the maximal activity was found in the middle of the growing phase (anagen). (Endocrinology 89: 1506, 1971)
Besieged Institutions and the Massachusetts Teacher Tests

Teacher testing was inaugurated in Massachusetts in 1998 and a 59% failure rate among test-takers led to public shaming of the teacher candidates and their colleges and universities in the media. Within a two-year time period, low-performing teacher education programs in Massachusetts initiated a wide range of test preparatory activities which led to a dramatic increase in their students' pass rates. The authors separate colleges and universities into three categories and examine their differentiated responses to teacher testing. Their finding that institutions of higher education have responded effectively to teacher testing does not preclude critique of teacher testing as currently practiced in Massachusetts.
Performance Evaluation in Bibliographic Instruction Workshop Courses: Assessing What Students Do as a Measure of What They Know.

Evaluation of student performance in bibliographic instruction (B.I.) has been, and continues to be, an area of interest to B.I. practitioners. The last 15 years have seen a number of excellent analyses and reviews of evaluation techniques. Many recent articles focus on evaluation methods used within specific B.I. programs.
A method for predicting RNA structure from amino-acid sequence data.

Abstract A method is presented that enables computation of the stability of hairpin loops in an RNA chain, knowing only the amino-acid sequence translated from that chain. The method is based on a statistical decoding procedure and a thenno-dynamic evaluation of bonding in terms of free energy. The decoding takes into account all triplets of bases for each amino acid. Every possible hairpin loop formed by bonding between base pairs is examined by a computer program. Using thermodynamic criteria, it is decided which loops have a high probability of being bound. For these, a free energy of loop formation is evaluated in order to predict stability. The method is tested on 54 amino-acid sequences obtained by translating 18 different tRNA's. The loops predicted from the amino-acid sequence are compared with their actual counterparts in the original nucleotide sequence. A strong positive correlation is observed between the predicted and actual stabilities. A hairpin loop predicted to be stable from the amino-acid sequence has, on average, a probability of 0.5 of being stable, 0.3 of being metastable and 0.2 of being unstable, in the actual nucleotide sequence. Various applications of this method to obtain information about sequence and structure in messenger RNA's are discussed.
Fluctuation analysis of an organic semiconductor–insulator interface

The space–charge region of an organic semiconductor (OS)–insulator interface is probed by analyzing the spontaneous, thermally driven drain current fluctuations of a field-effect transistor in which the OS forms the gate electrode. This so called “excess drain current noise” is the outcome of local fluctuations of the Fermi level, resulting from stochastic exchange of electrons between traps near the Fermi level. The power spectral density of this noise is characteristic of a Lorentzian process with a distribution of time constants, which is attributed to the disorder in the OS film. Furthermore, this disorder leads to local inhomogeneity of the work function in the film and a finite correlation length of the work function fluctuations. The measurement of work function noise is only possible within a correlation length of the OS–insulator interface. Through systematic variation of gate voltage, primary doping and secondary doping levels, the correlation length, disorder, and the trapping/de-trapping time constant are examined on polyaniline as a representative OS. A model is proposed for local work function variations and spontaneous charge-carrier fluctuations within polyaniline films with consequences for organic electronics using organic semiconductors.
Congress and the Emergence of Sectionalism: From the Missouri Compromise to the Age of Jackson – Edited by Paul Finkelman and Donald R. Kennon

Despite its misleading title (the book does not entirely concern links between Congress and sectionalism), this edited volume presents fresh interpretations of sectional struggles and Jacksonian‐er...
Automatic speckle cancellation techniques for multidither adaptive optics

Analytical and computer simulation results show that it is possible to restore speckle-degraded performance of multidither adaptive optics systems. Such systems are known to be vulnerable to interference caused by the motion of a speckle pattern across their receiver apertures. Analysis has shown that the primary effect of speckel is to amplitude-modulate the usual point-source intensity distribution reflected from a target glint. With large targets there is also an additive noise contribution from the intensity associated with reflections from the area surrounding the target glint. A method is described whereby the speckle interference is estimated and electronically canceled in order to restore the degraded adaptive performance.
A Discourse on Black Studies: Liberating the Study of African People in the Western Academy

This article seeks to examine the current phase in the discipline with a projection of what it could be in the future if researchers reevaluate their responses from the standpoint of African people...
Device-induced ventricular geometric remodeling: appraisal of critical issues.

BACKGROUND AND AIMS: Devices to therapeutically alter the shape of failing left ventricles are being developed by at least two laboratories. This review attempts to assess potential for benefit and possible negative consequences of the device concepts. METHODS AND RESULTS: Data from all known publications and scientific presentations were reviewed. Findings address four key issues: (1) Predictions, based on physical computations, of direct beneficial reduction in myocardial afterload are indeed computationally realistic and supported by effects reported experimentally. (2) Concerns that remodeling might necessitate unacceptably high epicardial contact pressure appear unfounded. Computational force modeling indicates that with optimization of contact area and contour, the expected degree of remodeling (approximately 20% effective radius reduction) might be achieved by epicardial pressures very near existing endocardial pressures, and in diastole, well below arterial perfusion pressures. Reported augmentation of systolic function suggests that there is no significant compromise of regional perfusion in acute (< or = 4 weeks) preclinical studies. (3) If intramural tangential shear stresses were sustained by local bending, detrimental tensile/compressive stresses might be introduced. However, microstructure predicts and reported evidence confirms rapid shear-stress relaxation. (4) The same reduction in wall-stress/chamber-pressure ratios that produces benefit during systole would simultaneously worsen diastolic same-volume stiffness. However, if better systolic contraction effects more complete emptying, operational volume range should become incrementally lower, at least compensating. This is supported by early published data. CONCLUSIONS: There appears to be solid computational and early experimental support for the concept of geometric ventricular remodeling. If one or more of the devices being tested should prove to be safe and effective, left ventricular geometric remodeling will be of substantial benefit in heart failure treatment.
Effect of organic acids on the growth and fermentation of ethanologenic Escherichia coli LY01.

Hemicellulose residues can be hydrolyzed into a sugar syrup using dilute mineral acids. Although this syrup represents a potential feedstock for biofuel production, toxic compounds generated during hydrolysis limit microbial metabolism. Escherichia coli LY01, an ethanologenic biocatalyst engineered to ferment the mixed sugars in hemicellulose syrups, has been tested for resistance to selected organic acids that are present in hemicellulose hydrolysates. Compounds tested include aromatic acids derived from lignin (ferulic, gallic, 4-hydroxybenzoic, syringic, and vanillic acids), acetic acid from the hydrolysis of acetylxylan, and others derived from sugar destruction (furoic, formic, levulinic, and caproic acids). Toxicity was related to hydrophobicity. Combinations of acids were roughly additive as inhibitors of cell growth. When tested at concentrations that inhibited growth by 80%, none appeared to strongly inhibit glycolysis and energy generation, or to disrupt membrane integrity. Toxicity was not markedly affected by inoculum size or incubation temperature. The toxicity of all acids except gallic acid was reduced by an increase in initial pH (from pH 6.0 to pH 7.0 to pH 8.0). Together, these results are consistent with the hypothesis that both aliphatic and mononuclear organic acids inhibit growth and ethanol production in LY01 by collapsing ion gradients and increasing internal anion concentrations.
Understanding Family Involvement in the College Experience Today

With the parents of today’s college students challenging traditional policies and philosophical approaches to student development, administrators must develop a consistent and coordinated message that meets their changing needs.
Unique mosaicism of tetraploidy and trisomy 8: Clinical, cytogenetic, and molecular findings in a live-born infant

We report on a live-born infant with mosaicism of tetraploidy and trisomy 8 who had craniofacial abnormalities, cardiac and genitourinary defects, agenesis of the corpus callosum, and anomalies of limbs. The infant died at age 14 weeks. Molecular studies were done on peripheral blood lymphocytes and cultured amniocytes to determine the origin of the cytogenetic abnormalities. On the basis of the results, we describe a possible mechanism to explain these abnormalities. To our knowledge, this infant represents the first reported case of mosaic trisomy 8 with a tetraploid cell line.
The Base of the Devonian and an Early Devonian Graptolite Succession in Central Nevada

A consensus has developed among stratigraphers interested in the Silurian-Devonian boundary that the Monograptus uniformis graptohte zone should be the base of the Devonian. Use of that zone as the base of the Devonian makes correlation with it relatively easy as significant evolutionary developments m several fossil groups have been recognized close to the base of the zone. If the base of the Monograptus uniformis zone is used as the base of the Devonian, then three, and possibly four, graptolite zones may be recognized in Lower Devonian rocks of central Nevada. The zones are characterized by evolution within the Monograptus hercynicus group as well as the appearance of Monograptus microdon, Linograptus posthumus, and Abiesgraptus. The Nevada zonal associations may be recognized in both carbonate rocks and in thrust-faulted argillaceous rocks. Most of the Nevada species appear to be slightly (probably subspecifically) different from their European relatives.
Diffusion-weighted MRI of the prostate at 3.0 T: Comparison of endorectal coil (ERC) MRI and phased-array coil (PAC) MRI—The impact of SNR on ADC measurement

Abstract Purpose To compare ADC values measured from diffusion-weighted MR (DW-MR) images of the prostate obtained with both endorectal and phased-array coils (ERC + PAC) to those from DW-MRI images obtained with an eight-channel torso phased-array coil (PAC) at 3.0 T. Methods The institutional review board issued a waiver of informed consent for this HIPAA-compliant study. Twenty-five patients with biopsy-proven prostate cancer underwent standard 3-T MRI using 2 different coil arrangements (ERC + PAC and PAC only) in the same session. DW-MRI at five b -values (0, 600, 1000, 1200, and 1500 s/mm 2 ) were acquired using both coil arrangements. On b = 0 images, signal-to-noise ratios (SNRs) were measured as the ratio of the mean signal from PZ and TZ ROIs to the standard deviation from the mean signal in an artifact-free ROI in the rectum. Matching regions-of-interest (ROIs) were identified in the peripheral zone and transition zone on ERC-MRI and PAC-MRI. For each ROI, mean ADC values for all zero and non-zero b -value combinations were computed. Results Mean SNR with ERC-MRI at PZ (66.33 ± 27.07) and TZ (32.69 ± 12.52) was 9.27 and 5.52 times higher than with PAC-MRI ((7.32 ± 2.30) and (6.13 ± 1.56), respectively) ( P b -values in the PZ and TZ were significantly lower with PAC-MRI than with ERC-MRI ( P Conclusion Lower SNR of DW-MR images of the prostate obtained with a PAC can significantly decrease ADC values at higher b -values compared to similar measurements obtained using the ERC. To address these requirements, clinical MR systems should have image processing capabilities which incorporate the noise distribution.
Financial Regulation in the United States: Lessons from History

History is institutional memory writ large. One looks at economic history to see what problems recur, what causes them to recur, what solutions have worked best in the past, and which interventions have made the problems worse. The authors argue that a moderately complex interaction between the workings of the financial sector, the way in which the political system is organized, and the administration of regulation makes perfect regulation of the financial sector extremely unlikely. Many of these problems arise as a result of conflicting incentives for those participating in and regulating the financial field. The authors find that some proposed solutions have improved matters but have costs, and that some proposed solutions have actually worsened problems in the financial sector. Peoples and governments never have learned anything from history, or acted on principles deduced from it. —Georg Wilhelm Friedrich Hegel, 1837
Tumor Immune Evasion

Host immunity can contribute to the elimination of malignant tumors, and cancer growth is often enhanced when immunity is suppressed. Many types of tumors have developed mechanisms to suppress the immune system in order to enhance their survival. Some tumors can escape immune detection by down-regulating their own expression of HLA class I proteins, rendering them invisible to cytotoxic T lymphocytes (1). More commonly, tumors actively suppress immune effector mechanisms by secreting proteins (such as TGF-β or IL-10) that inhibit effector CD8+ T cell responses and promote induction of Treg cells (2). On page _ of this issue, Shields et al. identify a novel mechanism used by melanomas to deceive the immune system (3). Chemokine CCL21-expressing melanomas recruit CCR7+ lymphoid tissue inducer (LTi) cells and reorganize portions of their tumor stroma into lymphoid tissue-like structures. This ingenuous stromal reconstruction directs the recruitment and maintenance of at least two types of suppressor immune cells, CD4+ regulatory T (Treg) cells and myeloid-derived suppressor cells (MDSC), both of which suppress immune recognition and effector functions, thereby promoting immune tolerance and tumor progression.
Introduction to “The Vampire in the Next Cubicle: The Americans with Disabilities Act and the Undead”

The Americans with Disabilities Act (ADA), first passed by the US Congress in 1990, signed into law by President George H.W. Bush on July 26, 1990 and later amended with the changes having taken effect on January 1, 2009, prevents, in certain situations, employers from discriminating against individuals who possess disabilities. While the ADA’s coverage in dealing with employment obstacles for individuals with disabilities is extremely broad, the civil rights protections guaranteed under the Act are similar to those that were established by the federal government to protect women and individuals who were members of racial, ethnic and religious minority groups from employment discrimination. Although disabled individuals have greatly benefited from the implementation of the ADAover the last two decades, the unemployment rate of disabled persons still remains significantly higher than the unemployment rate for nondisabled individuals. Additionally, one should also be cognizant of the fact that the vast majority of working-age disabled persons are not currently in the labor force so the “true” unemployment rate for such individuals is undoubtedly much greater than the official rate reported by the government. In this well-written, informative and provocative essay, Dr. David J. Prottas, Associate Professor in the Department of Management, Marketing, and Decision Sciences at Adelphi University, provides an excellent discussion of the ADA through analyzing the Act’s applications with regards to vampires, a group that many Americans appear to be extremely interested in as indicated by the recent spate of books, television shows, and movies that depict vampires and human beings interacting with each other. The author’s exploration of whether vampirism can be considered a disability under the ADA is written in the same spirit as that of “The Theory of Interstellar Trade” authored by Dr. Paul Krugman, the Nobel Prize winning economist. As is true of Dr. Krugman’s paper, Dr. Prottas’ treatise on the ADA displays a thoughtful analysis, combined with numerous insights, of an otherwise farcical topic. I welcome employment relations scholars from around the globe to contribute future essays analyzing any employment-related topic from a wide variety of theoretical perspectives. Moreover, if any of the journal’s readers would like to respond to particular essays published in the “Perspectives” Section, please do not hesitate to contact me with your proposal. I welcome both practitioner-based and scholarly-based articles. I hope that you enjoy this essay and find it most illuminating. Employ Respons Rights J (2012) 24:77 DOI 10.1007/s10672-012-9192-8