cssi/SciSciGPT-SciSciNet huggingface dataset:
Income Taxation and Heterogeneity

We study non-linear income taxation in a standard Mirrlees model, but allow for arbitrary heterogeneity in preferences. Our main theoretical result is a set of necessary and (locally) sufficient conditions for a tax schedule to be rationalizable within a very broad class of welfare functions. This test combines a standard first-order condition with a novel second-order condition. The latter reflects that, when households with the same income have very different taxable income elasticities, the planner can reform taxes to (a) sort households into different parts of the income distribution based on their elasticities and—at the same time—(b) exploit this separation with higher taxes on the less elastic. Moving to the data, we evaluate our test using novel estimates of the variance of taxable income elasticities by income bracket. In the NBER sample of tax returns from 1979 to 1990, our second-order condition fails every year. This implies that a “free lunch” is available through tax reform.
An overview of the legal aspects of human experimentation and research.

The early months of 1975 perhaps saw more alarm created within the community of professional persons who involve themselves in healing human beings or in conducting research involving human subjects than ever before. The notorious Boston abortion case [1] and the current flap over medical malpractice insurance rates [2] are merely illustrative. Throughout the whole realm of activity that may be generically described as research and experimentation on human subjects this controversy ramifies with consequences yet unknown. The purpose of this paper is to provide an overview of the legal aspects of research and experimentation on human subjects, directed somewhat toward behavioral research and particularly behavioral research in nonlaboratory settings.
Learning Skinner's Verbal Operants: Comparing an Online Stimulus Equivalence Procedure to an Assigned Reading.

The purpose of the present study was to compare the effects of an online stimulus equivalence procedure to that of an assigned reading when learning Skinner’s taxonomy of verbal behavior. Twenty-six graduate students participated via an online learning management system. One group was exposed to an online stimulus equivalence procedure (equivalence group) that was designed to teach relations among the names, antecedents, consequences, and examples of each elementary verbal operant. A comparison group (reading group) read a chapter from a popular textbook. Tests for the emergence of selection-based and topography-based intraverbal responses were then conducted, as were tests for generalization and maintenance. Overall, results suggest that the online equivalence procedure was not significantly more effective in promoting topography-based responses than the assigned reading. However, performance on selection-based tests was enhanced by the online equivalence procedure as was performance on topography-based tests when participants were required to provide operant names in response to consequences or examples. On average, the equivalence group performed at a level that was 10 percentage points (i.e., a full letter grade) above that of the reading group. The viability of the equivalence-based procedure is discussed in relation to the assigned reading.
Commercial Sex Work or Ukuphanda ? Sex-for-Money Exchange in Soweto and Hammanskraal Area, South Africa

This article introduces the conceptof ukuphanda, a Zulu verb that is used todescribe the sex-for-money exchanges that takeplace outside of commercial sex work in Sowetoand Hammanskraal area, South Africa. In linewith the ethnographic literature from othersareas of sub-Saharan Africa, it is argued thatwomen who exchange sex for money in taverns donot self-identify as commercial sex workers andexperience less stigma from the community. Unlike commercial sex work (as characterized bythe commercial sex work in Hillbrow,Johannesburg), which is understood to beassociated with short skirts and otherrevealing attire, sex-for-money exchange in thetaverns is viewed as more private, ambiguousand informal. Women who work as informal sexworkers, or “-phandela imali” (“tryto get money”), are understood to be usingsex-for-money exchange to survive financially.
Facilitation and depression at different branches of the same motor axon: evidence for presynaptic differences in release

This study provides evidence that a neuron can exhibit differences in activity-dependent transmitter release at two synaptic sites due to variations in the properties of its presynaptic terminals. Two muscles in the stomatogastric system of the lobster Homarus americanus are innervated by a single motor neuron but respond differently to that motor neuron's input, resulting in two different movements evoked by one motor neuron. During continued motor neuron stimulation, the gm8 muscle contracts slowly and maintains contraction, while the gm9 muscle contracts rapidly and then relaxes. These different muscle responses can be accounted for, in large part, by the properties of the respective neuromuscular synapses: the excitatory junctional potentials recorded in gm8 are initially small but summate and facilitate with repeated stimulation, while those in gm9 are initially large but depress with repeated stimulation. Presynaptic differences in neurotransmitter release contribute strongly to the divergent responses; reduction of the excitatory junction potential amplitude by partial postsynaptic receptor blockade or by desensitization does not change the amount of depression at gm9. However, reduction of neurotransmitter release with low-Ca2+, high-Mg2+ saline removes gm9 synaptic depression and reveals that both neuromuscular junctions exhibit frequency-dependent homosynaptic facilitation. Postsynaptic differences in muscle input resistance and muscle composition may enhance the effects of the divergent release properties, but are not responsible for the activity-dependent changes. Ultrastructural features of the nerve terminals on the two muscles are consistent with the differential output of the terminals; the synapses on gm9 are larger and have more presynaptic dense bars than their counterparts on gm8. These data suggest that the basis for the differences in transmitter release between the two muscles may be a higher density of release sites in the gm9 synapses that leads to a higher output of neurotransmitter, rapid depletion of transmitter stores, and synaptic depression.
Membranes of mammary gland: X. Adenosine triphosphate dependent calcium accumulation by golgi apparatus rich fractions from bovine mammary gland

Abstract Golgi apparatus rich fractions from lactating bovine mammary gland had an Mg 2+ -dependent, Ca 2+ -stimulated adenosine triphosphatase. These Golgi apparatus fractions also accumulated Ca 2+ in vitro. Accumulation of Ca 2+ required ATP and could be abolished by treatment either with low concentrations of deoxycholate followed by ultrasound, or by heating at 100 °C for 10 min. The adenosine triphosphatase activity of Golgi apparatus was strongly stimulated by low concentrations of Ca 2+ and moderately stimulated by high concentrations of K + . This activity was unaffected by Na + and was not inhibited by ouabain. The pH optimum for the Mg 2+ -dependent hydrolysis of ATP was 7.5, the K m was 5 × 10 −5 M and the activation energy was 6 000 calories/mole. This Mg 2+ -dependent adenosine triphosphatase activity was also found in rough endoplasmic reticulum, smooth microsomes and milk fat globule membrane, the latter membrane being derived directly from the apical plasma membrane. All of these membrane fractions had the ability to specifically accumulate Ca 2+ . Specific accumulation was highest with smooth microsomes and lowest with milk fat globule membrane with Golgi apparatus and rough endoplasmic reticulum being intermediate. These observations provide one plausible explanation for intracellular Ca 2+ accumulation and secretion into milk. Further, these results help explain the ultrastructural observations of casein micelle formation in secretory vesicles elaborated by Golgi apparatus.
A 10-bit, 3 V, 100 MS/s pipelined ADC

The design of a low-power 10-bit, 100 MS/s ADC is presented. The ADC is based on a pipelined architecture in which the number of bits converted per stage and the stage sizes were optimized to simultaneously achieve the desired linearity while minimizing the total power. When operated at 100 MS/s with a 3 V supply the ADC core dissipates 105 mW. The ADC was fabricated in a 0.35 /spl mu/m double poly CMOS process.
Stochastic resonance in speech recognition: differentiating between /b/ and /v/

Proposes that a neural mechanism has evolved which utilizes ambient noise in the recognition of weakly uttered, barely distinguishable monosyllable segments of speech, or phonemes; this mechanism fitting the characteristics of stochastic resonance. SR was originally conceptualized in 1980 to account for the periodicity of the ice ages, and has thus far been found to account for many natural, physical, and biological phenomena. Our experiments are averages over simulations, consisting of adding artificially produced midband (with respect to the system sampling frequency) Gaussian noise to pure analog speech waveforms. Conclusions are drawn from the comparison of true-positive to false-positive recognition results. The speech recognition algorithm relies on a recently published technique that finds the minimum difference between event times over a variety of time-scales and time-shifts. Our results propose a neurological supplement to the theoretical and experimental findings of physiological stochastic resonance, expressed in the form of Brownian motion assisting cochlear channel gating of sub-threshold sound signals.
Adaptive computing technology: an enabling processing technology for advanced sensor systems

Adaptive computing technology (ACT) represents one of the key processing technologies being investigated for advanced sensor systems. A processor architecture study was conducted for analyzing the feasibility of inserting aided target acquisition technology into military ground vehicles. Preliminary results show that, with the given set of constraints, an architecture augmented with ACT was able to meet many of the insertion requirements. Key aspects of ACT learned from the study are discussed in terms of emerging advanced sensor systems.
Star Captures by Quasar Accretion Disks: A Possible Explanation of the M-σ Relation

A new theory of quasars is presented in which the matter of thin accretion disks around black holes is supplied by stars that plunge through the disk. Stars in the central part of the host galaxy are randomly perturbed to highly radial orbits, and as they repeatedly cross the disk they lose orbital energy by drag, eventually merging into the disk. Requiring the rate of stellar mass capture to equal the mass accretion rate into the black hole, a relation between the black hole mass and the stellar velocity dispersion is predicted of the form MBH ∝ σ. The normalization depends on various uncertain parameters, such as the disk viscosity, but is consistent with observation for reasonable assumptions. We show that a seed central black hole in a newly formed stellar system can grow at the Eddington rate up to this predicted mass via stellar captures by the accretion disk. Once this mass is reached, star captures are insufficient to maintain an Eddington accretion rate, and the quasar may naturally turn off as the accretion switches to a low-efficiency advection mode. The model provides a mechanism to deliver mass to the accretion disk at small radius, probably solving the problem of gravitational instability to star formation in the disk at large radius. We note that the matter from stars that is incorporated into the disk has an average specific angular momentum that is very small or opposite to that of the disk, and we discuss how a rotating disk may be maintained as it captures this matter if a small fraction of the accreted mass comes from stellar winds that form a disk extending to larger radius. We propose several observational tests and consequences of this theory.
Direct identification of ventrointermediate nucleus of the thalamus on magnetic resonance and computed tomography images

Abstract OBJECTIVE The ventro-intermediate (Vim) nucleus of the thalamus is a commonly used target for the treatment of tremor. The thalamic fasciculus contains myelinated fibers, believed to play a role in the generation of tremor, that converge into a dense bundle at the inferior aspect of the Vim nucleus, making it visible on magnetic resonance (MR) and computed tomography (CT) images. This structure, therefore, can be visualized directly and targeted for thalamotomy. METHODS Thalamotomies were performed on nine patients (who have a follow-up of 13–23 months) with parkinsonian and essential tremors using MR and CT images. The tremor target was hypointense on MR images obtained in inversion recovery sequence and hypointense on CT images. It was therefore visualized, directly targeted, and probed. Stimulation studies were done to physiologically confirm accuracy of the probe placement and then a radiofrequency lesion was made. RESULTS Stimulation of the target identified as the Vim nucleus on MR and CT images produced responses similar to those expected from the Vim nucleus. After this site was lesioned tremor disappeared in all nine patients. CONCLUSION The Vim nucleus of the thalamus is visible on MR and CT images. Destruction of this target abolishes parkinsonian and essential tremors.
Fetal imaging in the skeletal dysplasias: overview and experience.

The skeletal dysplasias (osteochondrodysplasias) comprise a heterogeneous group of disorders that are characterized by generalized abnormalities of skeletal growth and development. Of approximately 125 well-described skeletal dysplasias, about 50 are clinically apparent and identifiable at birth. The prevalence of these dysplasias in the newborn is quite frequent and has been estimated to be between 3–4.5 per 10,000, and the overall frequency of skeletal dysplasias among perinatal deaths to be about 9 per 1,000. Over the past 23 years we have acquired an enormous experience in the International Skeletal Dysplasia Registry with skeletal dysplasias diagnosable at birth or earlier. More and more cases referred to the registry over the past 2 years have been diagnosed as abnormal by ultrasound during the second trimester. The results of our evaluation of almost 400 fetuses and stillborn babies with reference to detailed prenatal history and postmortem evaluation including radiographs, chondro-osseous morphology and even some biochemical and molecular studies are presented. The most common disorders diagnosed were osteogenesis imperfecta (OI), thanatophoric dysplasia, campomelic dysplasia and achondrogenesis type II. Twenty-two types of neonatally diagnosable skeletal dysplasias are discussed together with potential fetal (second trimester) ultrasound findings, the number of fetal ultrasound cases referred to this registry, the number of total cases of that disorder sent to our registry, and the inheritance pattern of that skeletal dysplasia. This information should prove helpful in the evaluation of future cases ascertained by ultrasonography in the second trimester.
Strong wall and transverse size effects on pressure drop of flow through open-cell metal foam

Abstract In applications where a fluid flows through the open pores of metal foam, the foam is treated as an infinite porous medium for which the Darcy law and the Forchheimer equation are applied, in order to describe the pressure drop and to obtain the permeability and form drag coefficient. However, in many practical applications the foam is confined, and depending on the transverse size of the foam (perpendicular to the flow direction), the confining walls and the size may have a strong effect on the velocity field and the resulting pressure drop and its behavior. Actually, for small confined foam size, the above flow relations may not be applicable, or they may require modifications in order to account for the added pressure drop due to the confining walls and size effects. Little or no attention has been paid to the transverse size of the foam perpendicular to the confining wall, which may explain some of the divergence in reported pressure drop in the literature. For confined cylindrical foam systems, this paper experimentally establishes a minimum diameter necessary for the foam to have diameter-independent pressure drop, i.e., negligible wall and size effects and constant permeability and form drag coefficient. This minimum diameter is obtained for two types of open-cell aluminum foam subjected to fully-developed airflow in the Forchheimer regime. Below this diameter, values of the two key flow properties show strong dependence on diameter. The Reynolds number ranged from approximately 15,000 to 115,000, and the foam diameters ranged from five to forty five cells for 10- and 20- pore per inch aluminum foam. The intertwined wall and size effect is isolated and studied.
Impact of major side branch on periprocedural enzyme elevation and long-term outcome in patients undergoing percutaneous coronary intervention and brachytherapy for in-stent restenosis

Side branch occlusion is 1 mechanism for the increase of creatine phosphokinase-MB after percutaneous coronary intervention and is associated with long-term adverse events. We studied 248 patients who underwent brachytherapy for in-stent restenosis with and without side branches, compared levels of creatine phosphokinase-MB with procedural, in-hospital, and long-term clinical outcomes, and found that patients with side branches have increased levels of creatine phosphokinase-MB after percutaneous coronary intervention and higher rates of restenosis, target vessel, and target lesion revascularization at 6-month follow-up.
Severity comparisons of specified and actual impulse tests

problem. Errors in pressure prediction will affect drag predictions much more than lift predictions because leading edge suction is an important factor in resultant pressure drag. In conclusion, it is shown that good estimates of pressure distributions can be derived from the combination of calculation procedures presented here. Also accurate lift and drag predictions can be made up to moderate angles of attack in transonic mixed flow.
Comments on the system Ag2SIn2S3

Abstract The high temperature polymorph of AgInS2 has been found to be orthorhombic with a =7.001 , b =8.278 , c =6.698 A , space group probably Pna21 with a distorted wurtzite structure. The phase transition temperature was found to be 620 ± 10°C and the melting point 880 ± 10°C. A new cubic spinel type phase was found at the composition AgIn5S8 with a =10.827 A .
The Phosphorus Requirements of Growing Chickens as Related to Age

Abstract THE phosphorus requirements for growing chickens have been studied chiefly by means of rations containing considerable cereal products. This has complicated the estimation of the requirement for phosphorus by the growing chicken due to the poor availability of phytin phosphorus as shown by Lowe, Steenbock and Krieger (1939) and Heuser, Norris, McGinnis and Scott (1943). Mitchell and McClure (1937) and Mitchell (1947) have assessed the phosphorus requirements of poultry and have shown that the requirements should decrease with increasing body size. However, most experiments on phosphorus requirement of chickens have consisted of feeding the same levels of phosphorus for the entire experimental period, thus masking any change in the actual requirements with advancing age or increasing body size. In considering the comparative nutritional requirements of different classes of farm animals, Guilbert and Loosli (1951) observed that the recommended allowances of phosphorus for growing chickens remain constant with advancing age whereas . . .
A single amino acid in gamma-aminobutyric acid rho 1 receptors affects competitive and noncompetitive components of picrotoxin inhibition

A class of bicuculline-insensitive gamma-aminobutyric acid (GABA) receptors, GABAC, has been identified in retina. Several lines of evidence indicate that GABAC receptors are formed partially or wholly of GABA rho subunits. These receptors generate a Cl- current in response to GABA but differ from GABAA receptors in a number of ways. Picrotoxin, widely accepted as a noncompetitive antagonist of GABAA receptors, displays competitive and noncompetitive antagonism of GABAC receptors in perch and bovine retina and GABA rho 1 receptors expressed in Xenopus oocytes. The aim of this study was to identify the molecular basis of the two components of picrotoxin inhibition of GABA rho 1 receptors. By using a domain-swapping and mutagenesis strategy, a difference in picrotoxin sensitivity between rho 1 and rho 2 receptors was localized to a single amino acid in the putative second transmembrane domain. Substitution of this amino acid with residues found in the analogous position in highly picrotoxin-sensitive glycine alpha and GABAA subunits increased the sensitivity of rho 1 mutants 10- to 500-fold. Importantly, the competitive component of picrotoxin inhibition of the rho 1 mutant receptors was almost eliminated. These findings demonstrate that an amino acid in the putative channel domain of GABA rho 1 receptors influences picrotoxin sensitivity and mediates agonist binding by an allosteric mechanism.
Improved acoustic modeling for speaker independent large vocabulary continuous speech recognition

The authors report recent improvements to an HMM (hidden, Markov model)-based, continuous speech recognition system. These advances, which include the incorporation of interword context-dependent units and position-dependent units and an improved feature analysis, lead to a recognition system which gives a 95% word accuracy and 75% sentence accuracy for speaker independent recognition of the 1000-word, DARPA resource management task using the standard word pair grammar (with a perplexity of about 60). With the improved acoustic modeling of subword units, the overall error rate reduction was over 42% compared with the performance results reported in the baseline system. The best results obtained so far using the word pair grammar gave 95.2% average word accuracy for the three DARPA evaluation sets. >
Experimenting with Welfare Reform: Emulating Success, Cutting Costs, or Racing to the Bottom?*

This article calls upon the social scientific research community to systematically assess policy devolution within American federalism through the lens of welfare reform. It asks specifically whether the benefits of policy devolution in this area—the opportunity to learn from policy experiments in similar states and the ability to tailor policies to individual state circumstances—outweigh the costs of devolution—possible racial biases across the states, incentives for cutting costs, and fears of a race to the bottom in benefits and eligibility criteria. A scientific research agenda for addressing these issues is developed. The contribution of De Jong et al. (2006) is assessed in terms of its advancement of this agenda. A path toward future contributions to this agenda is suggested.
Detecting mixtures from structural model differences using latent variable mixture modeling: A comparison of relative model fit statistics.

The accuracy of structural model parameter estimates in latent variable mixture modeling was explored with a 3 (sample size) × 3 (exogenous latent mean difference) × 3 (endogenous latent mean difference) × 3 (correlation between factors) × 3 (mixture proportions) factorial design. In addition, the efficacy of several likelihood-based statistics (Akaike's Information Criterion [AIC], Bayesian Information Ctriterion [BIC], the sample-size adjusted BIC [ssBIC], the consistent AIC [CAIC], the Vuong-Lo-Mendell-Rubin adjusted likelihood ratio test [aVLMR]), classification-based statistics (CLC [classification likelihood information criterion], ICL-BIC [integrated classification likelihood], normalized entropy criterion [NEC], entropy), and distributional statistics (multivariate skew and kurtosis test) were examined to determine which statistics best recover the correct number of components. Results indicate that the structural parameters were recovered, but the model fit statistics were not exceedingly accurat...
REVOLUTA regulates meristem initiation at lateral positions

While the shoot apical meristem (SAM) is indirectly responsible for the initiation of all above-ground postembryonic organs, in most plants the vast majority of these organs are directly initiated by lateral meristems. In Arabidopsis thaliana, the lateral meristems include flower meristems (FMs), which form on the flanks of the SAM, and lateral shoot meristems (LSMs), which develop in leaf axils. While significant progress has been made on the molecular genetic basis of SAM initiation during embryo development, relatively little is known about the initiation of meristems at lateral positions. Here we have characterized the phenotypic consequences and genetic interactions of mutations in the REVOLUTA (REV) gene, with an emphasis on the role of REV in lateral meristem initiation. Our observations indicate that REV is required for initiation of both LSMs and FMs, and likely acts in the same pathway as, and upstream of, known meristem regulators. We identified the REV gene and found it encodes a predicted homeodomain/leucine zipper transcription factor that also contains a START sterol-lipid binding domain. REV is the same as the IFL gene. REV was expressed at the earliest stages of LSM and FM formation. Within the inflorescence shoot meristem, REV expression appeared to predict 3--5 incipient flower primordia on the flanks of the SAM, and REV expression at stage 1 and stage 2 matched that of WUS and STM, respectively. We propose that REV acts at lateral positions to activate the expression of known meristem regulators.
Functional abrogation of p53 is required for T-Ag induced proliferation in cardiomyocytes.

Targeted expression of the SV40 large T-antigen oncoprotein (T-Ag) induces cardiomyocyte proliferation in the atria and ventricles of transgenic mice. Previous studies have identified the p53 tumor suppressor, p107 (a homologue of the retinoblastoma tumor suppressor), and p193 (a novel BH3 only proapoptosis protein) as prominent TAg binding proteins in cardiomyocyte cell lines derived from these transgenic mice. To further explore the significance of these protein-protein interactions in the regulation of cardiomyocyte proliferation, a transgene comprising the human atrial natriuretic factor (ANF) promoter and sequences encoding a mutant T-Ag lacking the p53 binding domain was generated. Repeated micro-injection of this DNA gave rise to genetically mosaic animals with minimal transgene content, suggesting that widespread cardiac expression of mutant T-Ag was deleterious. This notion was supported by the observation that the transgene was selectively lost from the cardiac myocytes (but not the cardiac fibroblasts) in the mosaic animals. Crosses between the mosaic mice and animals expressing a cardiac restricted dominant negative p53 resulted in transgene transmission with ensuing overt cardiac tumorigenesis. Transfection of the mutant T-Ag in embryonic stem (ES) cell-derived cardiomyocytes resulted in wide-spread cell death with characteristics typical of apoptosis. Co-transfection with a dominant negative p53 transgene rescued mutant TAg-induced cell death in the ES-derived cardiomyocyte cultures, resulting in a marked proliferative response similar to that seen in vivo with the rescued transgenic mouse study. These results indicate that T-Ag expression in the absence of p53 functional abrogation results in cardiomyocyte death.
Thenar insertion of abductor pollicis longus accessory tendons and thumb carpometacarpal osteoarthritis

Although the etiology of osteoarthritis of the thumb carpometacarpal (CMC) joint remains unclear, some theories have focused on variations in the local anatomy of the abductor pollicis longus tendon insertion. This cadaver study of 68 specimens analyzed the relationship between a thenar insertion of an accessory abductor pollicis longus tendon and the presence and severity of thumb CMC osteoarthritis. The joint cartilage surfaces were visually graded for degenerative changes. Thirty-five of 68 specimens (51%) had a thenar insertion, most frequently inserting on either the abductor pollicis brevis or opponens pollicis fascia or muscle belly. No significant association between a thenar insertion and thumb CMC arthritis was observed. Conversely, increasing age was noted to have a significant association with degenerative joint disease. Thus, these findings indicate that a thenar slip of the abductor pollicis longus tendon does not correlate with the presence or severity of CMC osteoarthritis.
An optimal real-time algorithm for planar convex hulls

An algorithm is described for the construction in real-time of the convex hull of a set of n points in the plane. Using an appropriate data structure, the algorithm constructs the convex hull by successive updates, each taking time O(log n), thereby achieving a total processing time O(n log n).
rSPACE: Spatially based power analysis for conservation and ecology

Summary Power analysis is an important step in designing effective monitoring programs to detect trends in plant or animal populations. Although project goals often focus on detecting changes in population abundance, logistical constraints may require data collection on population indices, such as detection/non-detection data for occupancy estimation. We describe the open-source R package, rSPACE, for implementing a spatially based power analysis for designing monitoring programs. This method incorporates information on species biology and habitat to parameterize a spatially explicit population simulation. A sampling design can then be implemented to create replicate encounter histories which are subsampled and analysed to estimate the power of the monitoring program to detect changes in population abundance over time, using occupancy as a surrogate. The proposed method and software are demonstrated with an analysis of wolverine monitoring in a U.S. Northern Rocky Mountain landscape. The package will be of use to ecologists interested in evaluating objectives and performance of monitoring programs.
U.S. Presidents and Their Roles in Emergency Management and Disaster Policy 1950-2009

This paper attempts both to rate the quality and breadth of presidential involvement in emergency management, as well as to examine the possible reasons for the differing quality. Using three major factors for evaluation, it is possible to review the presidential records from the second half of the twentieth century to today, and derive broad categorical assessments using a holistic methodology. The major factors are the ability and willingness to appropriately distinguish the needs and priorities of disaster management apart from civil defense needs and priorities, the selection of well-qualified disaster management leaders with a background in natural and accidental disasters, and the quality of implementation of programs including administrative execution, number and level of presidential disaster declarations, and timely presidential involvement in catastrophes. Using this framework, two presidents emerged as excellent, three as good, four as average, and two as poor. Interestingly, while some presidents learned from previous executive types of experiences, others did not. While some presidents learned from major catastrophes (focusing events) that occurred just before or during their administrations, others were hard-pressed simply to recover from especially disruptive or new disasters and failed to improve the system as a result. A consistent finding is that the performance of presidents in emergency management has had a growing effect on their overall reputations by the public and experts. Before 1950, presidential roles were extremely modest and expectations almost nonexistent. After Truman and through Regan, roles increased substantially and expectations were modest. From Clinton through Obama, the roles have continued to increase and expectations have become exceedingly high.
Delivering the Lateral Inhibition Punchline: It’s All About the Timing

Experimental and theoretical biologists have long been fascinated with the emergence of self-organizing patterns in developing organisms, and much attention has focused on Notch-mediated lateral inhibition. Within sheets of cells that may adopt either of two possible cell fates, lateral inhibition establishes patterns through the activity of a negative intercellular feedback loop involving the receptor, Notch, and its ligands Delta or Serrate. Despite a long history of intensive study in Drosophila, where the mechanism was first described, as well as in other organisms, new work continues to yield important insights. Mathematical modeling, combined with biological analyses, has now shed light on two features of the process: how antagonistic and activating ligand-receptor interactions work together to accelerate inhibition and ensure fidelity, and how filopodial dynamics contribute to the observed pattern refinement and spacing.
Analysis of Hydrogen Tunneling in an Enzyme Active Site using von Neumann Measurements.

We build on our earlier quantum wavepacket study of hydrogen transfer in the biological enzyme soybean lipoxygenase-1 by using von Neumann quantum measurement theory to gain qualitative insights into the transfer event. We treat the enzyme active site as a measurement device which acts on the tunneling hydrogen nucleus via the potential it exerts at each configuration. A series of changing active site geometries during the tunneling process effects a sequential projection of the initial, reactant state onto the final, product state. We study this process using several different kinds of von Neumann measurements and show how a discrete sequence of such measurements not only progressively increases the projection of the hydrogen nuclear wavepacket onto the product side but also favors proton over deuteron transfer. Several qualitative features of the hydrogen tunneling problem found in wavepacket dynamics studies are also recovered here. These include the shift in the “transition state” toward the reactant ...
Estrogen alters excitability but not morphology of a sexually dimorphic neuromuscular system in adult rats.

In rats, motoneurons of the spinal nucleus of the bulbocavernosus (SNB) innervate the bulbocavernosus (BC) muscle, which surrounds the base of the penis. The SNB/BC is a sexually dimorphic, steroid-sensitive neuromuscular system, which is critically important in male reproductive behavior. Androgens are necessary for the development, morphology, and function of the SNB/BC system. However, estradiol (E) is also necessary for the development of the SNB/BC system, and E is capable of maintaining BC EMG activity in adulthood. In this study, we used electrophysiological and anatomical methods to examine estrogenic effects on BC EMG activity. We used a modified H-reflex testing method to investigate polysynaptic reflex characteristics in intact males, castrates, and castrates treated short term with estradiol benzoate (EB). Measures of EMG activity, response latency, and spike count were altered in castrates, but maintained in EB-treated castrates to the levels of intact males. Furthermore, estrogenic effects were found in EMG activity that could be isolated to the periphery of the SNB/BC system. BC NMJ size and muscle fiber area have been demonstrated to be hormone sensitive, and we examined these for possible correlates of E's effects on BC EMG activity. BC muscles of intact males, castrates, and short-term EB-treated castrates were fixed and stained with zinc iodide and osmium tetroxide. NMJ size and muscle fiber area did not differ between groups. Together, these data suggest that E treatment results in changes in the neuromuscular periphery that maintain BC EMG activity, but this effect cannot be accounted for by changes in NMJ size or muscle fiber area. © 2003 Wiley Periodicals, Inc. J Neurobiol 56: 66–77, 2003
In Praise of Joan Robinson: Economics as Social Control

Economics is commonly understood to comprise efforts to describe, interpret, understand (in the sense of verstehen), and to explain the economy, its structures and processes of choice, and its regulative mechanism(s): in short, to constitute an attempt at positive, if not also normative, knowledge. This is the view held by most economists and historians of economic thought. George Shackle is the best known advocate of the existence of a second function performed by economics, namely, the provision of psychic balm. As Shackle understands the matter, in The Years of High Theory: All we can seek is consistency, coherence, order. The question for the scientist is what thought-scheme will best provide him with a sense of that order and coherence, a sense of some permanence, repetitiveness and universality in the structure or texture of the scheme of things, a sense even of that one-ness and simplicity which, if he can assure himself of its presence, will carry consistency and order to their highest expression. Religion, science and art have all of them this aim in common. The difference between them lies in the different emphases in their modes of search.
Adolescents adjusting to a group home environment: A residential care model of re-organizing attachment behavior and building resiliency

Abstract While many residential care models focus on the environment that existed within group homes, there is a need for these programs to concentrate on how some adolescents begin to adjust to life in a unique new environment. Nurturance and consistent care cannot be underestimated for displaced adolescents who have experienced a disruption in their attachment organization. This model includes two components: one that supports a stable and secure environment which is essential in re-organizing attachment behavior and another component of care and treatment that builds resilient adolescents through effective therapeutic teaching. This residential model has been designed to supplant unstable family models that many of the adolescents have experienced and to ultimately enhance the adolescent's resiliency in managing life after the group home. Case samples are included to illustrate the implementation of the model.
The Synthesis, Crystal Structure, Electrical Conductivity and Band Electronic Structure of (BPDT-TTF)2lCl2

Abstract (BPDT-TTF)2ICl2 is a synthetic metal salt composed of the electron donor molecule bis(propylenedithio)tetrathiafulvalene (BPDT-TTF, C12H12Sk) and the linear iododichloride anion, ICl2 −. The crystal structure of (BPDT-TTF)2ICl2, determined at 298 K and 120 K, closely resembles those of the organic metals and semiconductors based on bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF, C10H8H8), in that all of these materials contain sheetlike donor molecule networks sandwiched between anion layers. In contrast to the (BEDT-TTF)2X salts, however, there is a total absence of S···S contact distances less than ∼3.6 A (the van der Waals radius sum) within the donor-molecule network of (BPDT-TTF)2ICl2. In addition, each stack of BPDT-TTF molecules is also strongly dimerized. The lack of short S···S contact distances at both 298 K and 120 K appears to be a consequence of the bulky propylene groups of BPDTTTF compared to the smaller ethylene groups of the BEDT-TTF molecule. Based upon four-probe a.c. resistiv...
Downy woodpecker foraging behavior: foraging by expectation and energy intake rate.

I describe an artificial patch system that was used to study the foraging behavior of free-roaming downy woodpeckers (Picoides pubescens) in a woodlot in southeastern Michigan. The artificial “patches” used were thin logs into which were drilled small holes to hold food items (bits of sunflower seed kernels). Downy woodpeckers would systematically search the holes of a patch for food items and thus by manipulating the food distribution within the patches, the birds could be made to experience differing rates of energy intake while foraging.
CONTROL OF PIGMENT PRODUCTION IN MOUSE MELANOMA CELLS IN VITRO : Evocation and Maintenance

A clonally derived amelanotic melanoma cell line repeatedly has been forced to produce pigment by the inhibitor of DNA synthesis, I-beta-D-arabinofuranosylcytosine (ara-C) at sublethal levels. One ara-C-derived melanotic line has been cloned, and has continued to produce pigment for 2 years on normal medium. The inhibitor is most effective when administered to synchronized cells in four pulses on successive days at 1.8 x 10(-5)M during the S phase of the cell cycle. Colcemid at a sublethal concentration, and growth on medium solidified with agar also evoked pigment production in this line, but a large number of other inhibitors of biosynthetic processes did not, under the conditions tested. The melanotic lines are active producers of tyrosinase (DOPA oxidase), whereas the amelanotic line produces an inhibitor of tyrosinase activity. Both enzyme and inhibitor are labile at 4 degrees C and -20 degrees C, and decay of the inhibitor in homogenates of amelanotic cells reveals a low level of residual DOPA oxidase activity. The mean population doubling time of a cloned melanotic line is 23 hr, and that of a cloned amelanotic line 16.5 hr. A similar decrease in rate of growth is found in other melanotic lines and is believed to be a significant factor in maintaining this differentiated function. Rapid growth may be related to the production of an inhibitor by the amelanotic cells.
Phylodynamics of HIV-1 in lymphoid and non-lymphoid tissues reveals a central role for the thymus in emergence of CXCR4-using quasispecies.

Background During HIV-1 infection coreceptor switch from CCR5- (R5)- to CXCR4 (X4)-using viruses is associated with disease progression. X4 strains of HIV-1 are highly cytopathic to immature thymocytes. Virtually no studies have evaluated the HIV-1 quasispecies present in vivo within thymic and lymphoid tissues or the evolutionary relationship between R5 and X4 viruses in tissues and peripheral blood. Methodology/Principal Findings High-resolution phylodynamic analysis was applied to virus envelope quasispecies in longitudinal peripheral blood mononuclear cells (PBMCs) and lymphoid and non-lymphoid tissues collected post mortem from therapy naive children with AIDS. There were three major findings. First, continued evolution of R5 viruses in PBMCs, spleen and lymph nodes involved multiple bottlenecks, independent of coreceptor switch, resulting in fitter quasispecies driven by positive selection. Second, evolution of X4 strains appeared to be a sequential process requiring the initial fixation of positively selected mutations in V1-V2 and C2 domains of R5 variants before the emergence of high charge V3 X4 variants. Third, R5 viruses persisted after the emergence of CXCR4-using strains, which were found predominantly but not exclusively in the thymus. Conclusions/Significance Our data indicate that the evolution of X4 strains is a multi-step, temporally structured process and that the thymus may play an important role in the evolution/amplification of coreceptor variants. Development of new therapeutic protocols targeting virus in the thymus could be important to control HIV-1 infection prior to advanced disease.
Introduction to respiratory control in skeletal muscle.

It is well known that a linear relationship exists for submaximum exercise intensity and oxygen consumption. Most of the increase in oxygen consumption is by skeletal muscle mitochondria for the purpose of producing enough ATP to match the energy needs of the muscle. The control of mitochondrial ATP production in muscle when workload is varied is a complex process and remains a very active area of research. Thus, the purpose of this symposium is to discuss the factors involved in the coupling between increases in work and increased oxygen consumption by muscle. The program will begin with a consideration of the challenges faced by skeletal muscle when attempting to meet its energy demands and the intracellular strategies that have evolved to optimize energy delivery. Next the major control theories for mitochondrial respiration will be discussed. Finally, experiments will be presented that are designed to determine which of these theories are best suited for specific skeletal muscle fiber types. It is hoped that the information presented will increase our awareness of different energy supply-demand strategies among fiber types and how supply-demand strategies are optimized by endurance training.
AudioDAQ: turning the mobile phone's headset port into a universal data acquisition interface

Smartphone peripherals like the Square card reader, RedEye mini, and HiJack platform suggest a growing interest in using the headset port for more than just headsets. However, these peripherals only support sporadic activities in an efficient manner. Continuous sensing applications - like monitoring EKG signals - is possible but remains too inefficient for many realistic usage scenarios. We present AudioDAQ, a new sensor data acquisition platform. In contrast with prior work, AudioDAQ requires no hardware or software modifications on the phone, uses significantly less power, and allows continuous data capture over extended periods of time. The design is efficient because we draw all necessary power from the microphone bias voltage, and it is general because this voltage is present in every headset port. Data is modulated within the audible range, captured with the built-in voice recording app, and sent to a server for processing and storage. We show the viability of this approach by demonstrating an EKG monitor that can capture data continuously for hours.
Experimental evidence of the theoretical spatial frequency response of cubic phase mask wavefront coding imaging systems.

The optical transfer function of a cubic phase mask wavefront coding imaging system is experimentally measured across the entire range of defocus values encompassing the system’s functional limits. The results are compared against mathematical expressions describing the spatial frequency response of these computational imagers. Experimental data shows that the observed modulation and phase transfer functions, available spatial frequency bandwidth and design range of this imaging system strongly agree with previously published mathematical analyses. An imaging system characterization application is also presented wherein it is shown that the phase transfer function is more robust than the modulation transfer function in estimating the strength of the cubic phase mask.
Understanding the nature of system change: An interdisciplinary approach

The paper seeks to open up a debate on the nature of change at a conceptual and theoretical level. It argues that the abundance of methodologies and strategies for managing system change belies an acute lack of any clear understanding of the very nature and essence of change itself, whether it be institutional, technological, environmental or organizational. The paper calls for a greater comprehension of the fundamental dynamics of change, and highlights the considerable need for a solid theoretical basis from which to explore the complexities of system change. A cross-discipline approach is suggested, involving the analysis of change phenomena drawn from across the natural and physical sciences, deriving common characteristics and principles for abstraction into a general change framework. Several examples of the approach are described briefly, using change phenomenon taken from a range of disciplines. The paper concludes by outlining other subject areas which contain conceptually useful change phenomena worth investigating.