cssi/SciSciGPT-SciSciNet huggingface dataset:
Compliance with wetland mitigation standards in the upper peninsula of Michigan, USA.

The United States has lost about half its wetland acreage since European settlement, and the effectiveness of current wetland mitigation policies is often questioned. In most states, federal wetland laws are overseen by the U.S. Army Corps of Engineers, but Michigan administers these laws through the state’s Department of Environmental Quality (MDEQ). Our research provides insight into the effectiveness of the state’s implementation of these laws. We examined wetland mitigation permit files issued in Michigan’s Upper Peninsula between 2003 and 2006 to assess compliance with key MDEQ policies. Forty-six percent of files were out of compliance with monitoring report requirements, and forty-nine percent lacked required conservation easement documents. We also conducted site assessments of select compensatory wetland projects to determine compliance with MDEQ invasive plant species performance standards. Fifty-five percent were out of compliance. We found no relationship between invasive species noncompliance and past site monitoring, age of mitigation site, or proximity to roads. However, we found wetland restoration projects far more likely to be compliant with performance standards than wetland creation projects. We suggest policy changes and agency actions that could increase compliance with wetland restoration and mitigation goals.
Pseudomonas syringae type III secretion system effectors: repertoires in search of functions

The ability of Pseudomonas syringae to grow and cause diseases in plants is dependent on the injection of multiple effector proteins into plant cells via the type III secretion system (T3SS). Genome-enabled bioinformatic/experimental methods have comprehensively identified the repertoires of effectors and related T3SS substrates for P. syringae pv. tomato DC3000 and three other sequenced strains. The effector repertoires are diverse and internally redundant. Insights into effector functions are being gained through the construction of mutants lacking one or more effector genes, which may be reduced in growth in planta, and through gain-of-function assays for the ability of single effectors to suppress plant innate immune defenses, manipulate hormone signaling, elicit cell death, and/or display biochemical activities on plant protein targets.
Interaction of ethanol and congener contents in aversion conditioning to alcoholic beverages in rats

One hundred rats (Rattus norvegicus) received aversion training (beverage-LiCl pairings) with wine and distilled spirits conditioned stimuli (CSs) whose contents were high or low in congeners. Following training, each CS group received 8 days access to a 5% ethanol solution or to distilled water and then were tested for aversion to the original beverage CS. Groups that had received distilled water access between training and testing showed more persistent aversion effects to the wine CSs as a class than to the distilled spirits CSs. For each beverage class, aversion was greater to the CS with the higher content of congeners. Compared with distilled water access groups, groups that had received the 5% ethanol solution between training and testing showed reduced aversion effects to the beverage high in congener contents in each beverage class and no change in aversion to the low-congener beverage.
An annual cycle of steroid hormone concentrations and gonad development in the winter skate, Leucoraja ocellata , from the western Gulf of Maine

The winter skate, Leucoraja ocellata (Mitchill, 1815) is a large oviparous skate that is endemic to inshore waters of the western North Atlantic. The reproductive cycle of this species was characterized in monthly samples taken off the coast of New Hampshire, USA (42°15′N; 70°25′W), at depths of 9–107 m from November 2000 to October 2001. Plasma concentrations of the sex steroids testosterone (T), 17β-estradiol (E2), and progesterone (P4) were determined by radioimmunoassay in mature male and female skates. Changes in ovary weight, shell gland weight, and follicle size for 66 female skates were compared to patterns of all three steroid hormones. Beginning in January, ovary weight, shell gland weight, average diameter of the largest follicle, and plasma E2 increased steadily, culminating in a transient peak in July. This peak was followed by a steady decline in plasma E2 concentrations, which returned to the lowest values in December. Although T concentrations fluctuated throughout the year, a low concentration in July coincided with a peak in E2. Skates sampled in September, October, and November had the highest P4 concentrations, coinciding with the period of egg-case production. For males (n=64), annual cycles of T and E2 were compared to stages of spermatogenic development. Testosterone concentrations displayed two peaks, one in December/January and the other in July, which were associated with maximum spermatocyst concentration, while E2 peaks in February, June, and October coincided with maximum spermatocyte concentration. Along with our observations that some reproductive individuals were present throughout the year, these findings suggest that the winter skate has a partially defined reproductive cycle.
How racial cues affect support for American racial hierarchy among African Americans and Whites

Though racial hierarchy has been critical to American political development and continues to color much of American politics, little is known about the extent to which political factors mitigate or exacerbate support for the racial status quo. Using insights gained from research on system justification and racial priming, this paper examines how the use of negative racial cues by political elites affects support for American racial hierarchy among African Americans and Whites, where racial hierarchy is assessed both explicitly (with survey items) and implicitly (with the Implicit Association Test). Results from two original experiments suggest that the effect of elite racial cues on support for racial hierarchy is moderated by political ideology, and the strength and direction of the effects varies by racial group and the type of support for racial hierarchy – explicit or implicit – being examined.
Increased expression of the enzyme β1-4-galactosyltransferase is associated with human parotid neoplasms

Human biopsy samples of parotid gland neoplasms were examined for the level of enzyme activity of the glycosyltransferase, beta 1-4-galactosyltransferase. An analysis of an adenoid cystic carcinoma, Warthin's tumor, mucoepidermoid carcinoma, and five pleomorphic adenomas all revealed elevated levels of enzyme activity. Evidence for plasma membrane beta 1-4-galactosyltransferase activity was provided by membrane fractionation as well as intact cell enzyme assays. On the other hand, the major protein of human saliva, salivary alpha-amylase, was substantially reduced in the same tissue compared with adjacent normal parotid gland tissue. The trichloroacetic acid-soluble proteins isolated from gland homogenates were also reduced in two of the carcinoma samples but increased in the pleomorphic adenomas. Additionally, the proliferation of these cells, in vitro, could be retarded by culturing in media containing the galactosyltransferase specific modifier protein, alpha-lactalbumin, or the nucleotide sugar, UDP-galactose.
A discriminant analysis applied to methacholine bronchoprovocation testing improves classification of patients as normal, asthma, or COPD

Two discriminant functions, incorporating baseline measurements of pulmonary function and measures of airway responsiveness, were developed to improve patient classification into groups of normal, asthma, or COPD. Accuracy of group classification was compared between the usual laboratory method (single discriminating cut-off) and these new mathematically developed functions. Forty-five normal subjects, 27 asthmatic patients, and ten well-defined COPD patients were entered into the analysis. Measurements of airway responsiveness were determined by measurement of both specific airway conductance (SGaw) and spirometry (FEV 1 ) after sequential inhalation of methacholine. Results A single discriminant cut-off using measures of SGaw (PD35) or FEV 1 (PD20) does not sufficiently discriminate asthma from groups that contain normal and COPD subjects (67 to 71 percent predictive value). On the other hand, our discriminant functions demonstrated improved patient classification (positive predictive value, 88 to 89 percent). We conclude that bronchoprovocation tests used to evaluate the diagnosis of asthma should incorporate measures of baseline lung function into the analysis. This, we believe, is especially necessary when baseline lung function demonstrates minimal airflow obstruction and the possibility of other causes of airway disease exist.
The fourth test of general relativity

In the 'fourth test of general relativity' the gravitational acceleration of celestial bodies-the Earth and the Moon-were experimentally compared in the gravitational field of the Sun. Because such bodies obtain an appreciable fraction of their total mass-energy from their internal gravitational self-energy (5*10-10 for the Earth), this comparison of free-fall rates measures, among other things, how gravity pulls on gravitational energy and how gravitational energy contributes to the inertial mass of celestial bodies. Using high-precision laser ranging between Earth and reflectors on the Moon's surface, it was found that the Earth and Moon's acceleration in the Sun's gravitational field are the same to one part in 1011. Hypothesising that the gravitational to inertial mass ratio of a celestial body may differ from one by the order of the gravitational self-energy content of the body divided by the total mass-energy: MG/MI=1+ eta (UG/Mc2) eta being a dimensionless constant determined by gravitational theory, the lunar laser ranging experiment limits mod eta mod to less than 1.4*10-2. This experiment is consistent with general relativity which predicts eta =0, but scalar-metric tensor theories, such as the Brans-Dicke theory, vector-metric tensor theories and two-tensor theories of gravity are inconsistent with this experiment unless sufficient adjustable parameters are used.
Odysseans of the Twenty‐First Century

In his book Radical Evolution: The Promise and Peril of Enhancing Our Minds, Our Bodies—and What It Means to Be Human (2005), author-journalist Joel Garreau identifies four technologies whose synergistic activity may transform humankind into a state transcending present human nature: genetic, robotic, information, and nano (GRIN) technologies. If the GRIN technologies follow Moore's Law, as information technology has done for the past four decades, Homo sapiens and human society may be unimaginably different before the middle of this century. But among scientists, futurists, and other pundits there is no agreement on the nature and ramifications of this transformation. Based on dozens of interviews, Garreau sees three possible scenarios for our species. The Heaven Scenario foresees enhanced bodies and minds in a disease-free world, perhaps even immortality; the Hell Scenario warns of losing our identity as a biological entity and perhaps the demise of liberal democracy; the Prevail Scenario predicts that we will muddle through the GRIN technology revolution basically intact, as we have prevailed during past technological upheavals. In this review, these scenarios are examined in the context of Kuhn's “normal” versus “extraordinary” science and in the context of current understanding about gene function.
Potentiation by reserpine and tetrabenazine of brain catecholamine depletions by MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) in the mouse; evidence for subcellular sequestration as basis for cellular resistance to the toxicant

Abstract Administration to mice of the neurotoxicant MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) decreased striatal dopamine and, to a lesser extent, hippocampal noradrenaline levels when measured 2 weeks after the last dose of MPTP. Reserpine and tetrabenazine, inhibitors of the catecholamine vesicular transporter, potentiated the catecholamine depletions produced by MPTP in the hippocampus and striatum, respectively. These results are compatible with our hypothesis that sequestration of the toxic MPTP metabolite MPP + (1-methyl-4-phenylpyridinium) in the catecholamine storage vesicle retards the catecholaminergic toxicity of MPTP.
Pharmacological and Signaling Analysis of Human Chemokine Receptor CCR-7 Stably Expressed in HEK-293 Cells: High-Affinity Binding of Recombinant Ligands MIP-3β and SLC Stimulates Multiple Signaling Cascades

Abstract The chemokine receptor CCR-7 is expressed in T, NK, and dendritic cells in a time-ordered and stimulus-dependent manner. Thorough analyses of the pharmacological profiles of the recombinant ligands for CCR-7, MIP-3β/ELC/CK-beta 11, and SLC/Exodus-2/TCA4/6C-kine, using CCR-7-expressing HEK-293E transfectants determine that ligands both bind with a K d in the 100 pM range—10- to 100-fold greater affinities than published K d values. High-affinity binding of each ligand is associated with rapid mobilization of intracellular calcium and cell migration as predicted for chemokine GPCRs, and in keeping with more recent evidence, robust activation of mitogen-activated protein kinase (MAPK).
Processing complexity and sentence memory : evidence from amnesia

Abstract This study examines sentence memory as a function of linguistic processing complexity in amnesic patients. Sentence length as well as lexical and syntactic complexity were manipulated in two sentence repetition experiments. It was found that the amnesic patients performed considerably worse than the control subjects and that performance decreased: (1) when sentence length was increased by the addition of adjuncts compared to arguments of the verb; (2) when the verb selected more thematic frames; and (3) when sentences involved “empty” argument positions that must be linked to antecedents, particularly across clausal boundaries. These data showed how linguistic complexity affects sentence memory and implied that the amnesic deficit did not involve a generalized difficulty for materials of similar length, rather, the deficit was specific to certain representational types and processing routines.
Measurement of Supply Pin Current Distributions in Integrated Circuit Packages

Maintaining low supply impedance is a critical task in modern high-performance chip and system design, and this depends on how the current flows on the chip, package, and board power distribution layers. Using a simple inductive pickup loop previously described, we measure the per-pin via currents for a large VLSI chip in operation. Interestingly, the variation in AC current across the package was only 33%. indicating that for this chip current crowding was not an issue. Furthermore, we measured the board bypass capacitance currents as well, and found that the capacitors supplied between 80%n and 120% of the peak transient currents of the pins to which I hey were connected. Since the maximum current is only slightly larger than the current required by the attached pin, the board bypass capacitance primarily affects the pin it is connected to, and does not really bypass the other VDD pins in that region.
Five methoxy-2-methyl-3-indole acetic acid, a metabolite and alkali hydrolysis product of indomethacin, markedly inhibits platelet aggregation only in the presence of aorta or a product released by aorta

Abstract 5-methoxy-2-methyl-3-indole acetic acid (5MIAA) is a metabolite and alkali hydrolysis product of indomethacin. This indole derivative was previously found to be an effective in vivo inhibitor of platelet aggregation in an experimental model of microvascular injury in the mouse. In a standard aggregometer assay, the in vitro inhibitory action of 5MIAA was weak and failed to explain its in vivo effect. The present study employed two assay systems testing the capacity of 5MIAA to increase the aggregate inhibiting activity of the aorta. In one series of experiments the aorta, the drug and platelet rich plasma were incubated together, and in another series aliquots of aortic incubation media were transferred to PRP. Both types of study showed that 5MIAA interacts with the aorta and with a substance(s) produced by aortic wall to markedly inhibit aggregation stimulated by arachidonic acid. Thus, when 100μg/ml of 5MIAA, which by itself had a negligible effect on aggregation, was added to a cuvette containing both aorta and PRP, the inhibitory effect of the aorta was enhanced three fold. The substance with which 5MIAA interacts was eliminated by cyclooxygenase inhibitors, but direct tests of 5MIAA's ability to potentiate the effect of prostacyclin were unsuccessful.
Alcohol-related dementia: validation of diagnostic criteria.

Objective The authors sought to validate the diagnostic criteria for alcohol-related dementia. Methods The sample consisted of veterans consecutively admitted to a 240-bed VA Nursing Home Care Unit. Baseline and follow-up assessments included measures of cognition and functioning. The diagnosis and type of dementia was determined within 2 months of admission by a geropsychiatrist using patient interviews, chart review, and information from a structured collateral interview. Residents were followed for up to 2 years. Results Data were collected on 192 of the residents, of whom, 158 (82%) were diagnosed with some form of dementia. Alcohol-related dementia (ARD) was diagnosed in 16 residents (10.1%), probable Alzheimer dementia (AD), in 26 (16.5%); vascular dementia (VD), in 46 (29.1); and mixed or dementia of undetermined origin, in 70 (44.3%). Those with ARD were less cognitively impaired and were more often unmarried. Residents with ARD demonstrated a stabilization of both cognition and functional status, whereas those with AD and VD showed a general decline in both cognition and functional status. Conclusion These results serve to validate the diagnostic criteria for ARD and suggest that abstinence may be of clinical value in treating patients with dementia and alcohol dependence. Further research needs to be conducted to confirm the value of abstinence.
Nonlinear and Linear Site Response and Basin Effects in Seattle for the M 6.8 Nisqually, Washington, Earthquake

We used recordings of the M 6.8 Nisqually earthquake and its M L 3.4 aftershock to study site response and basin effects for 35 locations in Seattle, Washington. We determined site amplification from Fourier spectral ratios of the recorded horizontal ground motions, referenced to a soft-rock site. Soft-soil sites (generally National Earthquake Hazard Reduction Program [NEHRP] class E) on artificial fill and young alluvium have the largest 1-Hz amplifications (factors of 3–7) for both the mainshock and aftershock. These amplifications are correlated with areas of higher damage from the mainshock to major buildings and liquefaction. There are several indications of nonlinear response at the soft-soil sites for the mainshock ground motions, despite relatively modest peak accelerations in the S waves of 15%–22% g . First, the mainshock spectral ratios do not show amplification at 2–8 Hz as do the aftershock spectral ratios. Spectral peaks at frequencies below 2 Hz generally occur at lower frequencies for the mainshock spectral ratios than for the aftershock ratios. At one soft-soil site, there is a clear shift of the resonant frequency to a lower frequency for the mainshock compared with the aftershock. The frequency of this resonance increases in the coda of the mainshock record, indicating that the site response during the weaker motions of the coda is more linear than that of the initial S wave. Three of the soft-soil sites display cusped, one-sided mainshock accelerograms after the S wave. These soft-soil sites also show amplification at 10–20 Hz in the S wave, relative to the rock site, that is not observed for the aftershock. The cusped waveforms and 10–20-Hz amplification are symptomatic of nonlinear response at the soft-soil sites. These sites had nearby liquefaction. The largest amplifications for 0.5 Hz occur at soft-soil sites on the southern portion of the Seattle Basin. Stiff-soil sites (NEHRP classes D and C) on Pleistocence-age glacial deposits display similar spectral amplification for the mainshock and aftershock, indicating approximately linear response. The stiff-soil sites generally have moderate amplification (factors of 1.1–2.4) at 0.5 and 1 Hz. Amplifications at 1 and 5 Hz for all sites generally increase with decreasing shear-wave velocity measured in the top 30 m ( V s 30). However, larger amplifications at 0.5 and 1 Hz for sites with similar V s 30 values are observed for sites in the Seattle Basin, illustrating the amplification from the deeper (>30 m) sediments and the contribution from basin surface waves. Record sections for the mainshock and aftershock show that basin surface waves produce the peak velocities for many of the sites in the Seattle Basin and often dominate the amplitude at 1 Hz and lower frequencies.
Cyberpandemics: History, Inevitability, Response

As cyberspace has evolved into a large, dynamic, and tangled web of computing devices, engineers often fail to design in dependability properties-such as stability, robustness, and security-at the system level. Consequently, unintentional and malevolent actions taken in cyberspace have affected critical infrastructures in the physical world. These disturbances and systems' resultant undependable behavior can progress and spread like infectious disease-like cyberpandemics.
Taste thresholds of patients with cancer of the esophagus.

Twelve patients with untreated cancer of the esophagus and 14 control subjects matched for age, smoking, and alcohol consumption were tested for taste thresholds. Taste acuity for the four basic tastes was evaluated by three stimulus forced choice techniques (Henkin). There were no significant differences between the groups for detection and recognition thresholds for sour, salty, sweet, or bitter taste stimuli. Comparison of patients' detection and recognition thresholds with those of eight young healthy nonsmokers showed marked differences. Salivary urea nitrogen concentration was not different between patients and matched controls and did not correlate with bitter taste thresholds. Variable results have been reported for taste sensitivity in patients with malignant disease. In view of the results of this study and the many factors which influence taste acuity, it appears that a general statement regarding taste alterations in cancer patients cannot be made. Choice of appropriate control groups to correct for factors known to affect taste but not related to cancer per se is important for proper interpretation of taste testing results. Cancer 52:386-389, 1983.
Molecular genetics of Rett syndrome

Rett syndrome is a neurodevelopmental disorder affecting almost exclusively females. It affects approximately one in 15 000 females and is characterized by a loss of purposeful hand use, autism, ataxia and seizure. The disorder is usually sporadic, but rare familial cases have also been reported. Recently it has been shown that familial cases are an X-linked dominant disorder and the disease locus maps to Xq28. A candidate gene called methyl-CpG-binding protein 2 was identified from the Xq28 region and was shown to contain mutations in about 77% of Rett syndrome patients. Since the encoded protein was previously shown to be a global transcriptional repressor, undesired expression of yet unidentified genes that are normally repressed is considered to be pathogenic in Rett syndrome.
QMOD: physically meaningful QSAR

Computational methods for predicting ligand affinity where no protein structure is known generally take the form of regression analysis based on molecular features that have only a tangential relationship to a protein/ligand binding event. Such methods have utility in retrospective rationalization of activity patterns of substituents on a common scaffold, but are limited when either multiple scaffolds are present or when ligand alignment varies significantly based on structural changes. In addition, such methods generally assume independence and additivity of effect from scaffold substituents. Collectively, these non-physical modeling assumptions sharply limit the utility of widely used QSAR approaches for prospective prediction of ligand activity. The recently introduced Surflex-QMOD approach, by virtue of constructing physical models of binding sites, comes closer to a modeling approach that is congruent with protein ligand binding events. A set of congeneric CDK2 inhibitors showed that induced binding pockets can be quite congruent with the enzyme’s active site but that model predictivity within a chemical series does not necessarily depend on congruence. Muscarinic antagonists were used to show that the QMOD approach is capable of making accurate predictions in cases where highly non-additive structure activity effects exist. The QMOD method offers a means to go beyond non-causative correlations in QSAR analysis.
Improved recovery of hexachlorobenzene in adipose tissue with a modified micro multiresidue procedure

Using the described methodology the recovery of hexachlorobenzene from adipose tissue was significantly increased over that normally obtained with other multiresidue procedures. The recovery of other commonly encountered chlorinated hydrocarbon pesticides was not affected nor was the "background" from adipose tissue intolerable. Although extensive work has not been done, it is likely that improved recovery of hexachlorobenzene could be expected from other tissues.
Discrimination of schizophrenics with and without nervous system damage using the Luria-Nebraska Neuropsychological Battery.

The Luria-Nebraska Neuropsychological Battery was administered to 40 inpatient schizophrenics (17 non-brain-damaged and 23 brain-damaged) at a state hospital. Results indicated that 109 individual items as well as all 14 summary scales were significantly different between groups. Findings were reviewed with regard to clinical effectiveness of brain damage detection with the Luria-Nebraska in these populations and to supporting the concept of neuropsychological deficit gradients.
Clinical uses of lasers in dermatology

The accessibility of the skin to examination and study has permitted dermatologists to play an extremely important role in defining the clinical usefulness and limitations of many laser systems as well as developing innovative concepts, techniques and devices that further improved the effectiveness of laser treatment. As new laser technology evolved over the years, dermatologists have also helped define the specificity of laser-tissue interaction and employed the newly developed laser technologies in innovative ways which further expanded the usefulness of these devices. One of the most important concepts to be developed by dermatologists--selective photothermolysis--has led to the creation of a series of laser systems which have provided numerous unique advantages in the management of many common vascular and pigmented conditions of the skin and mucous membranes, even in infants and children. The net result of these technologic advances has been the creation of new and effective treatment techniques which have been so profoundly superior to existing technology that they have been rapidly incorporated into the daily practice of most dermatologists.
THE MULLITE CONTENT OF SOME AMERICAN TANK BLOCKS1

Samples of the various glass tank blocks manufactured in the United States were analyzed for mullite by the hydrofluoric-acid method.
Undergraduate biomedical imaging education.

Biomedical engineers, with their training in the life sciences as well as engineering, mathematics and physical sciences, are uniquely poised to both support and advance biomedical imaging technologies, which noninvasively capture the structure and function of living organisms. Biomedical imaging, born of Roentgen’s 1895 discovery of X-rays, now incorporates a wide variety of modalities that produce images reflecting the distribution and interaction of energy with the body’s tissues. Such images are acquired and used in many different ways including traditional medical imaging for diagnosis, therapy planning and assessment. Biomedical engineers also acquire and use images in the forms of standard videos to study gait analysis, endoscopic videos to guide therapeutic interventions, and still camera optical images to quantify biometrics and to read DNA microarrays. Strong undergraduate imaging curricula are critical to developing the essential human infrastructure needed to support biomedical imaging. This is especially true given the rapidly growing demand for engineers trained in the field of biomedical imaging. 6 This paper reviews current imaging curricula in biomedical engineering undergraduate programs and describes the best practices that should guide the development and refinement of biomedical imaging curricula. These curricula must capitalize on available resources—persons with expertise to teach imaging, computers with imaging software, imaging equipment if available and hands-on alternatives and simulations otherwise, as well as resources available on the internet as described in this paper. Incorporation of imaging examples to teach concepts already taught in basic science and mathematics courses helps address the lim
Size effects in multisubband quantum wire structures.

We present a Monte Carlo simulation of multisubband quasi-one-dimensional GaAs-${\mathrm{Al}}_{\mathrm{x}}$${\mathrm{Ga}}_{1\mathrm{\ensuremath{-}}\mathrm{x}}$As structures. The simulation includes polar-optical-phonon and inelastic acoustic-phonon scattering and investigates the effect of changing confinement on electron velocity. Even at low longitudinal fields, for confinements in the range 50--230 A\r{}, intersubband scattering has a profound effect on transport parameters. Under optimum conditions, differential mobility in excess of twice the bulk value at 300 K is obtained. Asymmetric geometry and high degree of confinement result in interesting differences from magnetotransport. In addition, resonance analogous to the magnetophonon effect occurs when the separation between lowest subbands is equal to the polar-optical-phonon energy.
Beyond dependency theory: national and regional patterns of underdevelopment in Guatemala

The historical and spatial pattern of Guatemala's underdevelopment is examined here, with special attention being paid to the differentiation of the national core and western periphery in the twentieth century. It is argued that Guatemala's underdevelopment cannot be traced to its long-standing export dependency, but rather to the uneven expansion of export-generated capital and its varying impact on relations of production in different parts of Guatemala's economy in the twentieth century. Evidence supporting this position consists of census data on changing patterns of urban growth and occupational characteristics of Guatemala's (operationally defined) economic cores and peripheries. This evidence is measured against explicit models of dependency structures and underdevelopment, as well as field and historical data on changing patterns of relations of production.
The importance of carbonization conditions on the character of phenanthrene coke and its graphitizability

Abstract The coking of liquid phenanthrene in a batch reactor was followed by measuring the formation of pyridine insolubles as a function of time over the temperature range 510–570°C. Following an induction period, the disappearance of pyridine solubles is first order, with the rate constants having an activation energy of 65 kcal/mole. This is significantly higher than the activation energy (46 kcal mole ) associated with the rate constants describing the carbonization of the isomer, anthracene. As the rate of carbonization increases, the low-temperature cokes produced decrease in their subsequent graphitizabilities. Further, the reactivity to air of the graphitized carbons is increased.
Pyruvic decarboxylase inhibition in ketoaciduria

A patient with intermittent episodes of cerebellar ataxia has been described (Pediat. 43:1025, 1969). The child excreted large amounts of urinary pyruvic acid during an episode which was studied in detail. Fibrobalst tissue culture cells were assayed for pyruvic decarboxylase and found to contain a low concentration of this enzyme. further examination of urine collected during the ataxic episode revealed that alanine was excreted in amounts proportional to that of pyruvic acid and that both metabolites were in concentrations inversely proportional to those of glutamic acid and aspartic acid. A child with late diagnosed, and hitherto untreated, phenylketonuria (PKU) was examined and found to have a high serum phenylalaline concentration and ketoaciduria. She was treated with a phenylalanine deprivation diet and urines collected in day and night 12-hour contiguous sequence. As the serum phenylalanine concentration fell there was a concomitant decrease in greatly elevated concentrations of urinary pyruvic acid into the normal range tother with a steady increase in concentrations of urinary glytamic acid. These observations suggested that inhibition of pyruvic decarboxylase could be an important mechanism in PKU as well as other ketoacidurias and that such a mechanism might involve the metabolism of glutamic acid. Experiments were carried out and showed that authentic α iso caproic acid and phenylpyruvic acid produce a marked decrease in the activity of pyruvic decarboxylase in vitro.
Advances in the assessment of cognitive skills using computer-based measurement

The impact of technology in the field of intellectual assessment has, for the most part, been limited to computerized administration and scoring. Anderson's (2001) theory of intelligence suggests that performance on traditional IQ measures is acquired via two main routes, thinking and dedicated processing systems known as modules. Empirical data used to support this relationship between the speed of basic processing and intellectual functioning have been evidenced primarily by correlations between measures of general intelligence and measures of inspection time (IT). These IT measures allow individuals to make a forced choice discrimination task without a motor component. Because only the time used to cognitively solve the problem is recorded, these responses typically occur in milliseconds. Many theorists (e.g., Burns & Nettelbeck, 2002; Deary, 2000; Jensen, 2006) consider IT to be a more "pure" measure of intelligence, because the influences of verbal skills, memory, and socialization are minimized and results are therefore considered to be more culture-fair. Until relatively recently, IT measurement was restricted to complex and expensive specialized laboratory equipment. This article describes the theoretical background and developmental process of a computer-based IT measure that is easily adaptable to accommodate the needs of the researcher.
On the definition and measurement of pleiotropy

Pleiotropy, a 103-year-old concept [1], refers to the phenomenon of one mutation affecting multiple traits. Compared with the fundamental importance of pleiotropy in genetics, development, evolution, and medicine, our empirical knowledge of the prevalence and mechanism of pleiotropy is scarce [2]. Given this context, Paaby and Rockman's recent Opinion article on pleiotropy and its empirical estimation [3] is timely, but several of their claims are debatable.
HUMAN REGULATORY T CELLS: A UNIQUE, STABLE THYMIC SUBSET OR A REVERSIBLE PERIPHERAL STATE OF DIFFERENTIATION?

FOXP3 is probably the best marker available currently for identifying natural regulatory T cells (Tregs) in mice and humans. Evidence from mouse literature suggests that natural FOXP3+ Tregs are formed in the thymus and expand in the periphery to contribute significantly to peripheral Tregs. In this review, we discuss recent reports that show that, in humans, the formation of FOXP3+ Tregs is a natural consequence of T cell activation and that de novo peripheral generation of FOXP3+ Tregs is a much more dominant source of circulating Tregs than natural thymically derived Tregs. We also suggest that the role of Tregs in human diseases must be reviewed in light of these new findings and great caution should be exercised in immunotherapeutic interventions that involve the modulation or generation of putative Tregs.
Simply read: erythrocytes modulate platelet function. Should we rethink the way we give aspirin?

The role of thrombosis in the precipitation of acute clinical syndromes of vascular occlusion, such as myocardial infarction and many strokes, is well established.1 The sequence of plaque fissure, platelet activation, and superimposed thrombogenesis underlies the use of platelet inhibitors, such as aspirin, in the prevention and treatment of such cardiovascular diseases.2 3 Perhaps less well appreciated is the multicellular contribution to thrombogenesis. Among the pioneers of this concept is the group associated with Aaron Marcus.2 3 Not only have they drawn our attention to the presence of erythrocytes (RBCs) and polymorphonuclear leukocytes (PMNs) within the thrombus, but they have provided in vitro evidence for bidirectional modulation of platelet function by these cell types. Whereas PMNs appear to diminish the capacity of platelets to respond to agonists,4 RBCs appear to facilitate platelet activation.5 6 Marcus and colleagues7 8 also provided evidence to suggest that interactions among platelets, RBCs, and PMNs may also facilitate the transcellular metabolism of bioactive lipids to novel species. These may, in part, contribute to the functional consequences of such cellular interactions.9 Santos and colleagues10 have now extended their in vitro observations of RBC-platelet interactions into the clinical domain. Before we consider their contribution, which appears in the current issue of Circulation, 10 it is worth providing the context for our present understanding of such phenomena. Almost 90 years ago, Duke11 described measurement of the bleeding time in three patients with anemia and thrombocytopenia. Transfusion raised the platelet count and shortened their prolonged bleeding times to normal. Despite the subsequent decline of the platelet count to pretransfusion levels, the bleeding time remained considerably shorter than before transfusion. Presciently, Duke observed that “since anemia is associated with a delayed bleeding time, this relief might be accounted for by the …
PIAGET AND THE ROLE OF GUIDED EXPERIENCES IN HUMAN DEVELOPMENT.

Stimnzary.-Considerable confusion has appeared in the literature relative to the nature and significance of experience, as it pertains to such investigations as those of Piaget. A planned program for developing the concepc of specific gravity was tested using experimental and control groups at the kindergarten and first grade levels. Stage of concept development was measured in individual interviews with the 39 Ss before and after administration of the learning program, which consisted of a 1-hr. period on each of three successive days. Resulrs indicated that (a) planned learning programs can affect significantly che development of the concepr of specific gravity at this age level and (b) the age levels for the development of the stages suggested by Piaget do not hold for a significant proportion of Ss when a planned learning program is applied. The purpose of this paper is to consider the nacure of "guided" or "planned learning experiences" and to arternpc some clarification of the problem of cheir role in h~unan developrnenc. In years pasc considerable confusion has appeared relacive to chis question, and the recenc revival of interest in Piaget's work on the developmenc of conceprs appears to have increased the confusion. Before proceeding, it is necessary to define the certns gzrded experiences and planned learning experiencer. In this paper che terms are used synonymously co designate those atcempcs to assisc a child or adult in learning (such as in learning the meaning of a concepr or in cultivating an appreciation) by developing, from an analysis of the nature of the learning cask and the nature of the learner, a planned sequence of experiences for mastering the task and by morivating the person ro participate in this experience. The planned sequence starts with che presenr development of the learner and leads step by scep to the objective. The cerm unplanned experiences, as ~~sed in this paper, refers to the experiences the environment happens to provide. The kind and sequence of experiences are determined by criceria ocher than the requirernencs suggested by an analysis of the specified learning cask. We do not know in detail the narure of the experiences and background of Ss examined by Piaget (1951)
Development of an 18-Megavolt Marx Generator

An 18-megavolt, 1 megajoule Marx generator has been constructed and tested to 11 MV as the primary energy store of the Hermes II flash x-ray machine. A geometrical arrangement for the capacitors that takes advantage of the stray capacities to provide a wide triggering range and fast Marx erection time was developed from model and circuit studies. The design parameters of the Marx were checked by constructing and testing a 4 MV, 100 kJ generator using components proposed for the 18 MV system. Spark gaps were developed specifically for the generator and have operated successfully for over 50,000 gap firings.
Abstract A68: Aromatase inhibition and chemopreventive potential of novel resveratrol derivatives

Resveratrol, a naturally occurring stilbene found in the human diet, has been shown to mediate a host of biological activities. It has been reported to display both estrogenic and anti‐estrogenic activities, depending on cell type and conditions, but inhibition of aromatase activity is weak (IC50 = 25 µM). We have conducted a systematic study in which about 60 substituted stilbenes were synthesized and evaluated for biologic potential. Several of these synthetic derivatives were found to inhibit aromatase activity with IC50 values in the sub‐micromolar range. Within the series, structure‐activity relationships demonstrated substitution of an amine group produced greater inhibition than a nitro group, and the position of these groups was of greater importance than the number and position of methoxy groups. Compound 1 [(E)‐4‐(3,5‐dimethoxystyryl)aniline] was one of the most potent inhibitors, with an IC50 of 0.31 µM, which is comparable to that of aminoglutethimide (IC50 = 0.2 µM). In addition, crystallographic analysis revealed compound 1 binds to quinone reductase 2 in an orientation similar to that of resveratrol, but demonstrates greater inhibitory potency. Compound 1 has been synthesized on a multigram scale, oral administration with laboratory animals indicates excellent absorption and good metabolic stability, and more advanced testing is underway. (Supported by program project P01 CA48112 awarded by the National Cancer Institute) Citation Information: Cancer Prev Res 2010;3(1 Suppl):A68.
Common basis for the mechanism of metallo and non-metallo KDO8P synthases.

Abstract The three-dimensional structures of metal and non-metal enzymes that catalyze the same reaction are often quite different, a clear indication of convergent evolution. However, there are interesting cases in which the same scaffold supports both a metal and a non-metal catalyzed reaction. One of these is 3-deoxy-D-manno-octulosonate 8-phosphate (KDO8P) synthase (KDO8PS), a bacterial enzyme that catalyzes the synthesis of KDO8P and inorganic phosphate (Pi) from phosphoenolpyruvate (PEP), arabinose 5-phosphate (A5P), and water. This reaction is one of the key steps in the biosynthesis of bacterial endotoxins. The evolutionary tree of KDO8PS is evenly divided between metal and non-metal forms, both having essentially identical structures. Mutagenesis and crystallographic studies suggest that one or two residues at most determine whether or not KDO8PS requires a metal for function, a clear example of “minimalist evolution”. Quantum mechanical/molecular mechanical (QM/MM) simulations of both the enzymatic and non-enzymatic synthesis of KDO8P have revealed the mechanism underlying the switch between metal and non-metal dependent catalysis. The principle emerging from these studies is that this conversion is possible in KDO8PS because the metal is not involved in an activation process, but primarily contributes to orienting properly the reactants to lower the activation energy, an action easily mimicked by amino acid side-chains.
Development Of Two Infrared Position Sensors

Reliable detectors for locating the position of a focal spot of visible radiation have been commercially available, but comparable infrared position sensors have not. This paper describes the development of two new detectors for infrared position sensing: (1) a room-temperature PbSe sensor, and (2) a liquid-nitrogen-cooled InSb sensor. With suitable electronics signal processing, each of these large sensor elements shows a linear response with x-and y-position displacement in the central region of the detector. These sensors are superior to previously reported detectors in threshold sensitivity, temporal frequency bandwidth, and drift. Detector characteristics and applications are discussed.© (1981) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Culture-Centered Computing: Social Policy and Development of New Information Technology in England and the United States

In addition to using computers, anthropologists now study computerization as a cultural process in its own right. A properly developed applied anthropology of computerization could help create more humane organizations as well as more effective information technology.This article contributes to the applied anthropology of computing by focusing on culture-centered computing, an approach to computing that results from a policy of deliberately using social and cultural means to influence the outcomes of the computerization process. The article is based primarily on anthropological fieldwork in Sheffield, England, where substantial computerization policy emerged in the 1980s, and secondarily in the Upper Mohawk Valley in New York, U.S.A.After placing studies of policy in the context of the anthropology of computing, the article summarizes the results of more general social science studies of computerization as a process of social change. Following an extended discussion of the development and adaptation of se...
Electroporation-mediated transformation of Arcanobacterium (Actinomyces) pyogenes.

Abstract Plasmids derived from pNG2 or RSF1010 were introduced into strains ofArcanobacterium (Actinomyces) pyogenesby electroporation. Electroporation conditions were varied systematically to give a maximum electroporation frequency of 3.7 × 105CFU/μg DNA at 1.5 kV/cm and 246 Ω, resulting in a time constant of approximately 10 ms. TheA. pyogenestransformants expressed plasmid-encoded resistance to chloramphenicol, erythromycin, kanamycin, and streptomycin. The source of incoming DNA affected the growth rate of transformants, but not the electroporation efficiency. This is the first report of genetic transformation of the veterinary pathogenA. pyogenes.