cssi/SciSciGPT-SciSciNet huggingface dataset:
A possible mechanism for amylase catalysis.

Abstract Arguments are presented which indicate that functional group catalysis by itself cannot account for the remarkable efficiency of amylases. On the basis of activation thermodynamics and X-ray analysis of lysozyme, a ring distortion is suggested as a possible additional interaction mechanism. To explain the exceptional rate of amylase catalysis, a reaction mechanism involving a combination of general acid catalysis by imidazole, ring distortion, and electrostatic solvation or general base catalysis or covalent bond formation with a carboxyl group is proposed. The overall stereochemistry of the reaction is ultimately controlled by the enzyme-directed approach of the solvent to the reaction center. The mechanism is consistent with both enzymic and physical organic data related to the hydrolysis of glycosides.
A generalized linear classification model with a smooth link function and predictors obtained from quantile spline fits to high-dimensional data

Abstract A classification model is developed for grading continuous recordings of the kind produced automatically by an analytical instrument. The explanatory variables of the model are features of the recordings extracted via (quantile) smoothing spline fits. The response variable is a grade and, in the training dataset, is an experts grade for a variety of recordings. A smooth inverse link function, allowing for nonlinearity in the experts grading scale, is incorporated in the model. The procedure is presented by way of an example that involves grading the quality of hypodermic syringes from friction profiles, obtained via tests conducted using an Instron™ machine. The linear predictor of the model describes grades, assigned by the expert to a training set of syringes, in terms of extracted features from associated friction profiles. A wide range of syringe quality is included in the training set. This allows application of the classification model to a large class of quality improvement studies. Using leave-one-out cross-validation, the prediction accuracy of the model is found to be about the same as that of the expert.
Divergence of classical trajectories and quantum chaos

Abstract This paper reviews our recent studies of the logarithmical in ħ effects in the statistical description of quantum chaos. We concentrate on the deviations from the universality in the level statistics and in the quantum correction to the conductivity. For the latter, we find that the weak localization correction to the current response is delayed by the large time t E = λ −1 z.sfnc; In h z.sfnc; , where λ is the Lyapunov exponent of the classical motion. For the former, we find the new contribution oscillating with the period π t E .
The World's Rain Forests: A Primer on Uniqueness

Primack, Richard, and Richard Corlett. 2005. Tropical rain forests: an ecological and biogeographical comparison. Blackwell, Malden, Massachusetts. ix + 319 p. $74.95, ISBN: 0-632-04513-2 (alk. paper).
Real-time load emulator for implementation of smart meter data for operational planning

This paper presents the design and implementation of a programmable load emulator that has the ability to emulate the active power-versus-time load data collected using smart meters. This load emulator can then be used as for hard-ware-in-the loop implementation during the development phase of energy management algorithms. In addition, the developed load emulator can simultaneously be programmed to a certain reactive power-versus-time curve. Although directed towards the emulation of daily load profiles, the developed load emulator can be used to emulate electric vehicles charging stations that sometimes interact with the utility grid, shipboard power system loads and even short and medium term pulsed loads. Hence, real time algorithms proposed for complex systems can be tested and optimized with this hardware-in-the-loop facility. In order to realize these capabilities, a PWM controlled converter was designed. Moreover, a vector decoupling technique was used to decouple the active and reactive powers and control them independently. The active power was controlled using an added leg to the converter to have a regulated DC bus voltage so that several curves can be emulated simultaneously. The operation of the developed load emulator was tested in real time and showed a very fast and accurate response. Experimental results show the validity of the developed converter and its applicability for smart grid research when real time control and operation is essential.
The formation of silicides in Mo-W Bilayer films on si substrates: A marker experiment

Use is made of the metallurgical similarity between Mo and W, and of their different atomic weights to study the diffusive formation of MoSi2 and WSi2. Thin film bilayers of Mo and W were deposited via e-beam evaporation upon Si single crystal substrates and annealed in an inert atmosphere at temperatures up to 1000‡C. The annealed samples were analysed by means of Rutherford backscattering and x-ray diffraction. The results indicate that Si is the dominant diffusing species. Observations on the formation of WSi2 are consistent with a process dominated by grain boundary diffusion through the W film.
The effects of reducing and alkylating agents on the acetylcholine receptor activity of frog sartorius muscle.

Exposure of frog sartorius muscle to the disulfide bond reducing agent, dithiothreitol, caused a decrease in the apparent affinity of their acetylcholine receptors for some agonists. Exposure to the oxidizing agent K3Fe(CN)6 reversed this effect. After reduction, the response to agonists was irreversibly blocked by exposure of the muscles to N-ethyl maleimide or 4-(N′-maleimido)phenyltrimethylammonium. However, contrary to what had been observed with electroplax, the blocking reaction did not occur at the acetylcholine binding site of the receptor.
Characterizing performance guarantees for multiagent, real-time systems operating in noisy and uncertain environments

Autonomous robots offer the potential to conduct Counter-Weapons of Mass Destruction (C-WMD) missions in an efficient and robust manner. However, to leverage this potential, a mission designer needs to be able to determine how well a robot system will operate in the noisy and uncertain environments that a C-WMD mission may require. We are developing a software framework for verification of performance guarantees for C-WMD missions based on the MissionLab software system and a novel process algebra approach to representing robot programs and operating environments.In this paper, we report on our initial research for the Defense Threat Reduction Agency (DTRA) in understanding what is required from a performance guarantee to give a mission designer the information necessary to understand how well a robot program will perform in a specific environment. We link this to prior work on metrics for robot performance. Using a simple mission scenario, we explore the implications of uncertainty in the four components of the problem: the robot program, and the sensors, actuators and environment with which the program is executed.
Parathyroid autotransplantation: Use of cryopreserved glands in an investigation of hypocalcemia

Abstract Parathyroid glands were removed from 12 dogs, cryopreserved, and autotransplanted: one-half of these dogs were made eucalcemic with 1,25-(OH) 2 -cholecalciferol during the peritransplant period while the other dogs were allowed to become hypocalcemic. The interval of hypocalcemia did not aid in autograft function success. Cryopreserved autotransplanted parathyroid glands can maintain calcium homeostasis in the dog.
Inside-out evacuation of transitional protoplanetary discs by the magneto-rotational instability

A newborn star is encircled by a remnant disc of gas and dust. A fraction of the disc coalesces into planets. Another fraction spirals inward and accretes onto the star1. Accreting gas not only produces observed ultraviolet radiation, but also drags along embedded planets, helping to explain otherwise mysterious features of observed extrasolar systems. What drives disc accretion has remained uncertain. The magneto-rotational instability (MRI), driven by coupling between magnetic fields and disc rotation, supplies a powerful means of transport2, but protoplanetary disc gas might be too poorly ionized to couple to magnetic fields1,2,3,4,5,6. Here we show that the MRI explains the observed accretion rates of newly discovered transitional discs7,8, which are swept clean of dust inside rim radii of ∼10 AU. Stellar coronal X-rays ionize the disc rim, activating the MRI there. Gas flows steadily from the rim to the star, at a rate set by the depth to which X-rays ionize the rim wall. Blown out by radiation pressure, dust largely fails to accrete with gas. Our picture supplies one concrete setting for theories of how planets grow and have their orbits shaped by disc gas9, and when combined with photo-evaporative disc winds10 provides a framework for understanding how discs dissipate.
The First Year Experience with the Dual Chamber ICD

In July 1997, a dual chamber pacemaker combined with a tiered therapy implantable cardioverter defibrillator (ICD) first became available in the United States. We report the first-year experience of one center in the United States with this dual chamber ICD. Of a total of 174 ICDs, 95 (55%) were dual chamber devices and 79 (45%) were single chamber. New dual chamber ICD insertions averaged 57.4 +/- 8.9 minutes, though there was a learning curve as the last 30 implants averaged 45.1 +/- 6.1 minutes with a negative slope to the regression line of procedure duration (-0.52, P < 0.05). New single chamber ICD implants were 18.5 minutes quicker (38.9 +/- 7.2 minutes). The most challenging implants were dual chamber upgrades (mean procedure duration 64.9 +/- 15.8 minutes), especially if there was a previously implanted pacemaker and ICD at separate sites. Indications for a new dual chamber device were grouped into classic pacemaker indications (52.5%), which comprised the Class I ACC/AHA guidelines, ICD-specific indications (24.6%), and other (23.0%). In the 34 patients undergoing dual chamber upgrade, the classic and ICD-specific groups were equal (47.0% each). Complications were rare (2.8%), though 3 (8.8%) of 34 undergoing a dual chamber upgrade developed late infections requiring explantation. In its first year, the dual chamber ICD has become a common device at our institution comprising 55% of new implants. As experience grows, we anticipate similar usage at most institutions.
A general method for high performance liquid chromatography of pyrrolizidine alkaloid free bases and N‐oxides

A reverse phase, ion-pair high performance liquid chromatographic method for the separation of five distinct structural subclasses of pyrrolizidine alkaloids has been developed. The system consists of a μBondapak CN or Nova-Pak Phenyl column in a radial compression apparatus, eluted isocratically with methanol: water (27:73) containing 0.01 M dibutylammonium phosphate. Symmetrical, well-resolved peaks were obtained for 30 pyrrolizidine alkaloids within a 15 min elution time. Both the free base and the N-oxide forms of the alkaloids can be analysed under the same conditions. The elution times are indicative of the relative polarities of the alkaloids being separated.
First-excursion failure of randomly excited structures

The probability for a randomly excited structure to survive a service time interval without suffering a first-excursion failure is determined analytically. The first-excursion failure occurs when, for the first time, the structural response passes out of a prescribed safety domain. The problem is formulated from the viewpoint of the Stratonovich-Kuznetsov theory of random points. The exact solution is expressed in two equivalent series forms, one reducible to Rice's "in and exclusion" series. The first order truncation of the second series corresponds to Poisson random points and the second order truncation to random points with "pseudo" Gaussian arrival rate. Numerical results are presented for a single-degree-offreedom linear oscillator under Gaussian white noise excitation based on these truncations and the model of nonapproaching random points suggested by Stratonovich.
The development of specific visual connections in the monkey and the goldfish: outline of a geometric theory of receptotopic structure.

Abstract The anatomical structure of the primate retino-striate system and the goldfish retino-tectal system are characterized by idealized geometrical domains. The physiological retinotopic mappings are then shown to be determined by the boundary conditions of the respective anatomical surfaces. This fact is interpreted as support for the “systems-matching” hypothesis of neural development of Gaze & Keating. It is suggested that the development of specific neural mappings may be, in part, a variational problem in which two neural surfaces establish connections as “smoothly” as possible. Dirichlet's Principle supplies a quantitative definition of the term “smooth”—the average physiological magnification factor of the neural mapping is minimized, subject to the boundary conditions of the available tissue. Three developmental rules are formulated, which deal respectively with gross specificity, polarity, and detailed map construction. The latter rule, based on Dirichlet's Principle, supplies a link between the classical theory of fields and developmental neurobiology. Specific experimental tests are outlined in the goldfish visual system, and a general discussion of global approaches to neural structure and function is presented.
Characterization of steroid production in cultured human choriocarcinoma cells

Progesterone is the major steroid synthesized by the JEG-3, BeWo, and JAR cell lines of choriocarcinoma. A lesser amount of pregnenolone is produced. The 17alpha-hydroxy derivatives of these steroids are only minimally present in three lines. The addition of fetal calf serum to the culture medium modestly increases the synthesis of these steroids, but increases the quantity of 17beta-estradiol produced by 30- to 90-fold. The addition of dehydroepiandrosterone, dehydroepiandrosterone sulfate, androstenedione, androstenediol, and testosterone was shown to stimulate 17beta-estradiol synthesis. There is a clear dose-response relationship between the amount of testosterone added and the quantity of 17beta-estradiol produced. These results indicate that 3beta-hydroxysteroid dehydrogenase-isomerase, 17beta-ol dehydrogenase, and aromatase are active in cultured choriocarcinoma cells, whereas 17beta-hydroxylase and 17-20 desmolase do not appear to be functional in these cells. It is concluded that the stereoidogenic capabilities of choriocarcinoma cells in culture are similar to those of the in vivo placenta and support their use as an experimental model of placental steroidogenesis.
Entry-level jobs: First rung on the employment ladder or economic dead end?

The ability of young workers to move from dead-end jobs into higher-wage jobs which have better career prospects is greatly influenced by the individual’s characteristics, local labor market conditions, and his or her human capital. This paper examines the characteristics of entry-level jobs of young workers in the 1980s with emphasis on how education and training influence the types of jobs held. The incidence of post-school training is quite low even though all types of post-school training raise wages significantly. Company-provided training reduces the probability that a young worker will leave his or her employer, while off-the-job training increases the ability of employees, especially young women, to move out of a dead-end job.
Employment responses to international liberalization in Chile

Abstract This paper investigates employment patterns in Chile following a substantial trade liberalization. The paper examines patterns of job creation and job destruction and relates these patterns to firms' size and trade orientation.
A linear-time algorithm for finding a minimum spanning pseudoforest

Abstract A pseudoforest is a graph each of whose connected components is a tree or a tree plus an edge; a spanning pseudoforest of a graph contains the greatest number of edges possible. This paper shows that a minimum cost spanning pseudoforest of a graph with n vertices and m edges can be found in O(m+n) time. This implies that a minimum spanning tree can be found in O(m) time for graphs with girth at least log(i)n for some constant i.
Functional repair of a mutant chloride channel using a trans-splicing ribozyme.

RNA repair has been proposed as a novel gene-based therapeutic strategy. Modified Tetrahymena group I intron ribozymes have been used to mediate trans-splicing of therapeutically relevant RNA transcripts, but the efficiency of the ribozyme-mediated RNA repair process has not been determined precisely and subsequent restoration of protein function has been demonstrated only by indirect means. We engineered a ribozyme that targets the mRNA of a mutant canine skeletal muscle chloride channel (cClC-1) (mutation T268M in ClC-1 causing myotonia congenita) and replaces the mutant-containing 3′ portion by trans-splicing the corresponding 4-kb wild-type sequence. Repair efficiency assessed by quantitative RT-PCR was 1.2% ± 0.1% in a population of treated cells. However, when chloride channel function was examined in single cells, a wide range of electrophysiological activity was observed, with 18% of cells exhibiting significant functional restoration and some cells exhibiting complete rescue of the biophysical phenotype. These results indicate that RNA repair can restore wild-type protein activity and reveal considerable cell-to-cell variability in ribozyme-mediated trans-splicing reaction efficiency.
Caudate intracellular response to thalamic and cortical inputs.

Abstract Intracellular recordings of cat caudate neuronal responses evoked by stimulation of the cerebral cortex or of a number of thalamic sites were made. The predominant response was an EPSP-IPSP sequence. A higher percentage of “pure” EPSPs were recorded from the stimulation of centromedian-parafascicular region than from stimulation of other thalamic sites. The outcomes of these experiments were generally in agreement with recent reports concerning the fine structure of the caudate nucleus. The combined anatomical and physiological data suggest that the great majority of striatal input fibers are excitatory and the majority of interneurons are inhibitory in their synaptic effects.
Synthesis and Decomposition of an Ester Derivative of the Procarcinogen and Promutagen, PhIP, 2-Amino-1-methyl-6-phenyl-1H-imidazo[4,5-b]pyridine: Unusual Nitrenium Ion Chemistry

The food-derived heterocyclic amine (HCA) carcinogen 2-amino-1-methyl-6-phenyl-1H-imidazo[4,5-b]pyridine, PhIP, is often generated in the highest concentration of the HCAs formed during broiling and frying of meat and fish. Although it is considered to be an important contributor to human cancer risk from exposure to HCAs, the chemistry of PhIP metabolites that presumably react with DNA to initiate carcinogenesis has received only cursory attention. We have synthesized the ester derivative N-pivaloxy-2-amino-1-methyl-6-phenyl-1H-imidazo[4,5-b]pyridine, 1b, and investigated its chemistry in aqueous solution. Although 1b was too unstable to isolate, we could characterize it by NMR methods in DMF-d7, a solvent in which it is stable at −40 °C. It decomposed rapidly in aqueous solution, but its conjugate acid, 1bH+, is not reactive. The nitrenium ion, 2, was trapped by N3- to form the unusual tetrazole adduct, 16. In the absence of N3-, the expected hydration products of 2 were not detected, but the reduction ...
Energy-gap reduction in heavily doped silicon: Causes and consequences

Abstract The authors review briefly the existing theoretical treatments of the various effects that contribute to the reduction of the energy gap in heavily doped Si, namely electron-electron and electron-impurity interactions and the effect of disorder in the impurity distribution. They then turn to the longstanding question why energy-gap reductions extracted from three different types of experiments have persistently produced values with substantial discrepancies, making it impossible to compare with theoretical values. First, they demonstrate that a meaningful comparison between theory and experiment can indeed be made if theoretical calculations are carried out for actual quantities that experiments measure, e.g. luminescence spectra, as recently done by Selloni and Pantelides. Then, they demonstrate that, independent of any theoretical calculations, the optical absorption spectra are fully consistent with the luminescence spectra and that the discrepancies in the energy-gap reductions extracted from the two sets of spectra are caused entirely by the curve-fitting procedures used in analyzing optical-absorption data. Finally, they show explicitly that, as already believed by many authors, energy-gap reductions extracted from electrical measurements on transistors do not correspond to true gap reductions. They identify two corrections that must be added to the values extracted from the electrical data in order to arrive at the true gap reductions and show that the resulting values are in good overall agreement with luminescence and absorption data. They, therefore, demonstrate that the observed reduction in emitter injection efficiency in bipolar transistors is not strictly due to a gap reduction, as generally believed, but to three very different effects.
Nitrification in the euphotic zone as a source for nitrite, nitrate, and nitrous oxide at Station ALOHA

We measured chemoautotrophic bacterial nitrification rates in the lower euphotic zone at the North Pacific Time-series Station ALOHA using low-level chemical assays and inhibitor-sensitive radiocarbon uptake experiments. These measurements were compared with independent nitrification rate estimates based on nitrous oxide distributions, nitrate assimilation rates based on nitrate changes during an in situ incubation, and historical estimates of nitrification and nitrate assimilation from this region. Ammonium oxidation rates ranged from 1.0 to 137.4 hmol m-3 d-l, and nitrite oxidation rates varied from undetectable to 138.0 pmol m-3 d-l. Conservative estimates of depth-integrated euphotic zone nitrification rates from the complete three-cruise data set were 0.69 mmol rnd2 d-l for nitrite oxidation and 1.64 mmol m-2 d-l for ammonium oxidation. The highest nitrification rates were found below the primary nitrite maximum, suggesting a significant contribution of euphotic zone ammonium oxidation to the nitrite pool below but not within this feature. A mass balance of nitrous oxide indicates that this gas is produced within the euphotic zone at a rate of 1.68-7.94 pmol m-2 d-l. The nitrous oxide production rate provides an independent estimate of the total euphotic zone nitrification rate in the range of 0.34-l .59 mmol m-2 d-l. We estimate that the total euphotic zone nitrification rate is 47-142% of the concurrent nitrate assimilation rate, indicating that nitrification in the euphotic zone is an important source of regenerated nitrate. Nitrification, the microbiologically mediated oxidation of ammonium to nitrite and nitrite to nitrate, is a key process in the global nitrogen cycle (Ward 1986). In the marine environment, the vertical flux into the cuphotic zone of nitrate regenerated by nitrification in deep water is considered crucial to ecosystem stability through its support of new primary photosynthetic production (Eppley and Peterson 1979). However, nitrifying bacteria are also active within the euphotic zone, especially within the primary nitrite maximum (Olson 198 1
Ultrasonic Microbubble Destruction Stimulates Therapeutic Arteriogenesis Via the CD18-Dependent Recruitment of Bone Marrow–Derived Cells

Objective— We have previously shown that, under certain conditions, ultrasonic microbubble destruction creates arteriogenesis and angiogenesis in skeletal muscle. Here, we tested whether this neovascularization response enhances hyperemia in a rat model of arterial insufficiency and is dependent on the recruitment of bone marrow–derived cells (BMDCs) to treated tissues via a β2 integrin (CD18)-dependent mechanism. Methods and Results— Sprague-Dawley rats, C57BL/6 wild-type mice, and C57BL/6 chimeric mice engrafted with BMDCs from either GFP + or CD18 −/− mice received bilateral femoral artery ligations. Microbubbles (MBs) were intravenously injected, and one gracilis muscle was exposed to pulsed 1 MHz ultrasound (US). Rat hindlimbs exhibited significant increases in adenosine-induced hyperemia and arteriogenesis compared to contralateral controls at 14 and 28 days posttreatment. US-MB–treated wild-type C57BL/6 mice exhibited significant arteriogenesis, angiogenesis, and CD11b + monocyte recruitment; however, these responses were all completely blocked in CD18 −/− chimeric mice. The number of BMDCs increased in US-MB–treated muscles of GFP + chimeric mice; however, GFP + BMDCs did not incorporate into microvessels as vascular cells. Conclusion— In skeletal muscle affected by arterial occlusion, arteriogenesis and hyperemia can be significantly enhanced by ultrasonic MB destruction. This response depends on the recruitment, but not vascular incorporation, of BMDCs via a CD18-dependent mechanism.
Kinematics and control of rigid body manipulation with a flexible sheet and its application to a rehabilitation bed

A new method for manipulation of a rigid body with a flexible sheet is presented, and the method is applied to repositioning of bedridden patients. A key feature of the proposed system is that the body is not securely connected to the sheet and the contact region between the body and the sheet changes dynamically during manipulation. The use of a soft flexible sheet and the untethered nature of manipulation, makes the system particularly well suited to handling the human body. We present an application to a rehabilitation bed for repositioning a bedridden patient to alleviate secondary ailments such as bedsores. In order to prevent injury to the patient's fragile skin, it must be ensured that the patient does not slip on the sheet during repositioning. We model the system and present a no-slip condition based on system parameters. The model is used to develop a closed loop control strategy for coordinating the motions of multiple actuators of the prototype bed. The prototype bed can successfully reposition test subjects using the control strategy developed.
Natural selection on inflorescence color polymorphisms in wild Protea populations: The role of pollinators, seed predators, and intertrait correlations

 Premise of the study: The processes maintaining fl ower color polymorphisms have long been of evolutionary interest. Mechanistic explanations include selection through pollinators, antagonists, local environments, drift, and pleiotropic effects. We examined the maintenance of infl orescence color polymorphisms in the genus Protea (Proteaceae) of South Africa, in which ~40% of species contain different color morphs.  Methods: We studied 10 populations of four bird-pollinated Protea species and compared adult performance, fl oral and leaf morphology, vegetative pigmentation, germination, and seedling survival between co-occurring pink and white morphs. We also tested for differences in pollination success and pre-dispersal seed predation.  Key results: White morphs produced seeds 10% heavier and 3.5 times more likely to germinate, which all else being equal, should fuel positive selection on white. In one studied population per species, however, white morphs were more susceptible to seed predation by endophagous larvae. Pollinators had no morph-specifi c effects on female fecundity, as measured by amount or probability of seed set. Differences in stem color indicated that white morphs produced smaller quantities of pigment and associated compounds throughout, possibly explaining their higher seed palatability.  Conclusions: Our fi ndings suggest a mechanism for some white protea polymorphisms: deleterious pleiotropic effects on pink morphs are occasionally offset by reduced losses to seed-eating larvae. Because trends were repeated across species, we suggest that similar processes may also occur in other proteas, placing a new emphasis on seed predators for infl uencing some of South Africa ’ s amazing fl oral diversity.
Children's assessments of corporal punishment and other disciplinary practices: The role of age, race, SES, and exposure to spanking

Abstract African-American and Anglo-American children's assessments of four disciplinary methods (spanking, reasoning, withdrawing privileges, and time-out) were investigated with 108 children ages 6–10 years old and one of their parents. Children watched videos depicting a child being disciplined and then rated each discipline method. Reasoning was rated as most fair, spanking as least fair. Spanking was regarded most effective for immediate compliance but not for long-term behavior change. Children with medium high levels of exposure to spanking were more likely to regard it as the best disciplinary technique compared with children with low or high exposure levels. Younger children rated spanking as fairer than older children. No differences were found between African-American and Anglo-American children's assessments after controlling for exposure to spanking and socioeconomic status. Implications about the role of children's assessments of discipline for internalization are discussed.
RIP60, a mammalian origin-binding protein, enhances DNA bending near the dihydrofolate reductase origin of replication.

Abstract Replication of the Chinese hamster dihydrofolate (dhfr) gene initiates near a 281-bp HaeIII fragment of stably bent DNA that binds RIP60, a 60-kDa origin-specific DNA-binding protein that has been purified from HeLa cell nuclear extract (L. Dailey, M. S. Caddle, N. Heintz, and N. H. Heintz, Mol. Cell. Biol. 10:6225-6235, 1990). Circular permutation assays showed that stable DNA bending in the dhfr origin region fragment was due to the presence of five oligo (dA)3-4 tracts, designated bend elements B1 to B5, that are spaced 10 bp apart. DNA bending directed by elements B1 to B5, as assessed by anomolous migration of DNA fragments on polyacrylamide gels, was accentuated at 4 degrees C. Bend element B5, which is in inverse orientation relative to elements B1 to B4, overlaps an ATT-rich motif that comprises the RIP60 protein-binding site. Gel mobility shift assays with circularly permuted bent DNA fragments and purified RIP60 showed that RIP60 markedly enhanced DNA bending of the dhfr origin region sequences. These results suggest that, as in many plasmids, bacteriophages, and eucaryotic viruses, mammalian DNA-binding proteins may enhance DNA bending near origins of replication during initiation of DNA synthesis.
The resilient regional labour market? The US case

This article examines the ability of regional labour markets to rebound by growing the middle class or increasing wages. Using data on US metros, we identify regions that are transformative in terms of achieving a new equilibrium or reversing their path dependency. We then use discriminant analysis to identify the factors behind this resiliency. Regional resilience is rare, and changing a region’s path is easier than achieving a new equilibrium. Among the most important factors behind regional transformation are the ability to attract immigrants, retain manufacturing, and innovate a high-tech economy. The diversity of outcomes suggests that a simple strong versus weak market dichotomy is insufficient to characterize regional resiliency, and a wide array of policies will be necessary.
Industrial distributor selling: The roles of outside and inside sales

Abstract This paper examines the current practice of industrial distributor selling, focusing on the roles played by the outside and inside sales forces. Based on benchmark survey results, the present composition, responsibilities, and compensation programs of outside and inside sales forces are compared and contrasted. Some predictions are given on likely changes in selling practices, drawing upon interviews with managers, and managerial implications of them, are offered.
Is a Good Teacher a Good Teacher for All? Comparing Value-Added of Teachers With Their English Learners and Non-English Learners

Districts, states, and researchers are using value-added models with increasing frequency to evaluate educational policies and programs, as well as teachers and other educators individually. Despit...
Catalyst-free synthesis routine to indium nitride nanowires

A vapor-solid growth strategy (catalyst free) of one-dimensional materials was employed to synthesize hexagonal wurtzite InN nanowires with large yield as much as gram quantities on a hot-wall CVD system. Morphology characterization by FE-SEM revealed uniform nanowires with 700/spl deg/C growth temperature have /spl sim/70 nm average diameter and /spl sim/5-30 micron length. EDS, XRD and micro-Raman spectroscopy characterization showed the formation of high-purity hexagonal wurtzite InN nanowires. Further structural characterizations by high-resolution TEM and low-temperature electrical characterizations (mobility and carrier density) are being undertaken.
Isolation rearing affects sequential organization of motor behavior in post-pubertal but not pre-pubertal Lister and Sprague–Dawley rats.

Objecti6e: Dopaminergic and serotonergic modulation potently influences the sequential organization of rat movements in a simple unconditioned motor paradigm. Rats reared in social isolation post-weaning differ profoundly from their socially reared litter mates on behavioral, neurochemical, and neuroanatomical measures. This investigation examined (1) whether social isolation significantly affects the sequential organization of rat movements, (2) whether these changes occur at different ages, and (3) whether these changes differ across strains. Method: male Lister and Sprague‐Dawley rats reared in isolation post-weaning and socially reared controls were tested at 2 and 8 weeks post-weaning, in the Behavioral Pattern Monitor for 30-min sessions. The amount of activity and the spatial patterns of movements as measured by both the spatial scaling exponent and the fluctuation spectrum of local spatial scaling exponents were assessed in 10-min intervals. Results: Habituation of locomotor activity was significantly attenuated in isolation reared rats during the 30-min sessions irrespective of strain. Spatial patterns of movements were significantly affected by isolation rearing in movements in post-pubertal but not pre-pubertal Lister and Sprague‐Dawley rats. The spatial scaling exponent and the fluctuation spectrum analysis revealed a shift towards straight, distance-covering, and repetitive movements rather than a complex re-organization of the behavioral repertoire. Conclusions: Isolation rearing profoundly affects the sequential organization of movements in post-pubertal rats, suggesting that emerging behavioral dysfunctions parallel developmentally those found in patients with schizophrenia. © 1998 Elsevier Science B.V. All rights reserved.
Adaptive speciation: the role of natural selection in mechanisms of geographic and non-geographic speciation.

Recent discussion of mechanism has suggested new approaches to several issues in the philosophy of science, including theory structure, causal explanation, and reductionism. Here, I apply what I take to be the fruits of the "new mechanical philosophy" to an analysis of a contemporary debate in evolutionary biology about the role of natural selection in speciation. Traditional accounts of that debate focus on the geographic context of genetic divergence--namely, whether divergence in the absence of geographic isolation is possible (or significant). Those accounts are at best incomplete, I argue, because they ignore the mechanisms producing divergence and miss what is at stake in the biological debate. I argue that the biological debate instead concerns the scope of particular speciation mechanisms which assign different roles to natural selection at various stages of divergence. The upshot is a new interpretation of the crux of that debate--namely, whether divergence with gene flow is possible (or significant) and whether the isolating mechanisms producing it are adaptive.
Sin Stock Returns

In this article, the authors examine the issue of how social values affect economic values. Based on a small subset of the stock universe that has been generally associated with sin-seeking activities, such as alcohol consumption, adult services, gaming, tobacco, weapons, and biotech alterations, the authors find that a sin portfolio produced an annual return of 19% over the study period, unambiguously outperforming common benchmarks in terms of both magnitude and frequency. Several likely reasons for the positive excess returns in sin stocks are identified. The authors argue that trustees or fiduciaries who develop institutional investment policy statements should fully understand the economic consequences of screening out stocks of companies that produce a product inconsistent with their value systems. In addition, institutional investors should question if the cost to uphold common social standards is worthwhile.
Effects of 9-cis-Retinoic Acid on the Insulin-Like Growth Factor Axis in Former Smokers

Purpose Insulin-like growth factor (IGF) axis has been associated with the risk of lung cancer. 9-cis-retinoic acid (9-cis-RA) has shown potential chemopreventive activities in former smokers. This study was designed to evaluate the effects of 9-cis-RA on IGF axis in former smokers to identify any benefit the retinoid may have in preventing lung cancer. Patients and Methods Serum concentrations of IGF-I, IGF binding protein (IGFBP)-3, and their molar ratio (IGF-I/IGFBP-3) were measured with radioimmunoassay kits in stored blood samples from the participants of an original chemoprevention trial. The participants had ceased smoking for at least 12 months and were randomly assigned to receive 3 months of daily oral 9-cis-RA (100 mg) or placebo. All statistical tests were two-sided. Results A total of 111 samples from the study's baseline and 84 samples from the 3 months treatment were analyzed. The serum concentrations of IGF-I and IGF-I/IGFBP-3 at baseline were significantly lower in female than in male par...
GMSK modulation for deep space applications

Due to scarcityof spectrum at 8.42 GHz deep space X-band allocation, many deep space missions are now considering the use of higher order modulation schemes instead of the traditional binary phase shift keying (BPSK). One such scheme is pre-coded Gaussian minimum shift keying (GMSK). GMSK is an excellent candidate for deep space missions. GMSK is a constant envelope, bandwidth efficient modulation whose frame error rate (FER) performance with perfect carrier tracking and proper receiver structure is nearly identical to that of BPSK. There are several issues that need to be addressed with GMSK however. Specifically, we are interested in the combined effects of spectrum limitations and receiver structure on the coded performance of the X-band link using GMSK. The receivers that are typically used for GMSK demodulations are variations on offset quadrature phase shift keying (OQPSK) receivers. In this paper we consider three receivers: the standard DSN OQPSK receiver, DSN OQPSK receiver with filtered input, and an optimum OQPSK receiver with filtered input. For the DSN OQPSK receiver we show experimental results with (8920, 1/2), (8920, 1/3) and (8920, 1/6) turbo codes in terms of their error rate performance. We also consider the tracking performance of this receiver as a function of data rate, channel code and the carrier loop signal-to-noise ratio (SNR). For the other two receivers we derive theoretical results that will show that for a given loop bandwidth, a receiver structure, and a channel code, there is a lower data rate limit on the GMSK below which a higher SNR than what is required to achieve the required FER on the link is needed. These limits stem from the minimum loop signal-to-noise ratio requirements on the receivers for achieving lock. As a result of this, for a given channel code and a given FER, there could be a gap between the maximum data rate that BPSK can support without violating the spectrum limits and the minimum data rate that GMSK can support with the required FER depending on the type of GMSK receiver that is used.
Third-Party Web Tracking: Policy and Technology

In the early days of the web, content was designed and hosted by a single person, group, or organization. No longer. Webpages are increasingly composed of content from myriad unrelated "third-party" websites in the business of advertising, analytics, social networking, and more. Third-party services have tremendous value: they support free content and facilitate web innovation. But third-party services come at a privacy cost: researchers, civil society organizations, and policymakers have increasingly called attention to how third parties can track a user's browsing activities across websites. This paper surveys the current policy debate surrounding third-party web tracking and explains the relevant technology. It also presents the FourthParty web measurement platform and studies we have conducted with it. Our aim is to inform researchers with essential background and tools for contributing to public understanding and policy debates about web tracking.
Twenty-five year mortality of US servicemen deployed in Vietnam: predictive utility of early drug use

Large numbers of young men were exposed to high-quality opiates for a relatively short time period during military service in Vietnam. This study examined the relationships of opiate and other drug abuse before, during, and shortly after their time of service in Vietnam with the subsequent 25-year mortality among the cohort of 1227 US Army enlisted returnees and their matched civilians previously studied in 1972 and 1974. Composite factor scores of a variety of drug use measures and other individual behavioral measures were selected separately for three time periods around service in Vietnam from over 120 measures associated with mortality. Results of path analytic models applied to selected significant measures showed that both in-Vietnam and post-Vietnam drug use factors were large and significant predictors of mortality, controlling for pre-service drug use, continuity to later drug use, and demographic and other behavioral measures. The magnitude of the direct effect of drug use on mortality was larger than those of the covariates that were entered in the path analyses, except age. Notwithstanding the high remission rate from opiate addiction, drug use in Vietnam had considerable predictive utility for premature death in this cohort. In light of the re-emergence of increased heroin use since the mid-1990s, the findings point to the importance of early intervention of drug use and comorbid problems for today's youth now initiating heroin use.
Nonparametric Bayesian Texture Learning and Synthesis

We present a nonparametric Bayesian method for texture learning and synthesis. A texture image is represented by a 2D Hidden Markov Model (2DHMM) where the hidden states correspond to the cluster labeling of textons and the transition matrix encodes their spatial layout (the compatibility between adjacent textons). The 2DHMM is coupled with the Hierarchical Dirichlet process (HDP) which allows the number of textons and the complexity of transition matrix grow as the input texture becomes irregular. The HDP makes use of Dirichlet process prior which favors regular textures by penalizing the model complexity. This framework (HDP-2DHMM) learns the texton vocabulary and their spatial layout jointly and automatically. The HDP-2DHMM results in a compact representation of textures which allows fast texture synthesis with comparable rendering quality over the state-of-the-art patch-based rendering methods. We also show that the HDP-2DHMM can be applied to perform image segmentation and synthesis. The preliminary results suggest that HDP-2DHMM is generally useful for further applications in low-level vision problems.
The "PI" (Placement And Interconnect) System

"PI" is an advanced LISP-based placement and interconnect system for custom NMOS or CMOS (single-layer metal) designs. When fully implemented, PI will handle placement of arbitrarily-sized rectangular modules, routing of power and ground, signal routing, and compaction. In this paper we briefly review the structure of PI, and present details on the signal-routing heuristics, focusing on the definition of "channels", the global router, the "crossing placer", and the channel routers. The signal router is fully operational; the rest of PI is currently being coded and will be more fully described in later papers and theses.
Structural properties of polystyrene oligomers in different environments: a molecular dynamics study

We have performed detailed molecular dynamics simulations to investigate the effects of solvation and confinement on the structure of polystyrene (PS) oligomers in four different environments, melt, concentrated solution, dilute solution and confined concentrated solution at 450 K and 1 bar, respectively. Local packing of the monomers and the solvent (toluene, good solvent) molecules were monitored by means of radial distribution functions (RDFs). We have also investigated bond, angle, and dihedral angle distributions of the monomers. End-to-end distances, radii of gyration and persistence lengths were calculated to characterize the static properties. The chain in the dilute solution was found to exhibit more stretched conformations. Dilution effect of the solvent was observed in the RDFs between the monomer centers. Only slight conformational changes in the polymers were observed by solvation. The effect of confinement was mainly seen in the density profiles, which showed an oscillatory behavior in the confined system.
The influence of estradiol and diet on small intestinal glucose transport in ovariectomized rats.

Although gender differences exist for intestinal absorption of nutrients and drugs, the possible role estradiol may play in modulating nutrient transport has not been established. Therefore, small intestine glucose transport was measured 1 week after administering estradiol to ovariectomized rats fed diets high in carbohydrate (C) or protein (P). Rats treated with estradiol ate 21% less (P < 0.05) and lost body mass (7%; P < 0.05) but did not have smaller intestines. Administration of estradiol increased rates of glucose transport, but only when the rats were fed the C diet. These findings indicate that estradiol causes a disconnect between food intake and the dimensions and nutrient transport capacities of the small intestine. Furthermore, the responses to estradiol are influenced by diet composition, are not of the same magnitude for rats and dogs, and can be predicted to affect systemic availability of nutrients and drugs.
Public Participation and the Transatlantic Trade and Investment Partnership

This article explores how the Transatlantic Trade and Investment Partnership, a free trade agreement currently being negotiated between the United States and European Union, might enhance agency decision-making by expanding opportunities for stakeholder input on both sides of the Atlantic. It compares the primary mechanisms for public participation in the United States and European Union, identifies the primary goals each side seeks to achieve, and highlights possible reforms that might improve participatory processes on both sides.
Status Inconsistency and Drinking Behavior

For more than a quarter of a century, status inconsistency has been invoked by analysts to explain problematic behavior and illness. A fundamental problem has been distinguishing between the effects of inconsistencies between two or more social positions and the effects of the positions themselves. This study examines the effects of status and status inconsistency on patterns of alcohol consumption. The principal findings are that as ascribed status exceeds achieved status, quantity of beer and liquor consumed per occasion increases, and that as achieved status exceeds ascribed status, frequency of wine and liquor consumption increases.