cssi/SciSciGPT-SciSciNet huggingface dataset:
Collective Buckling of Periodic Soft Nanostructures on Surfaces and Promotion for Nanolithography

Mechanical instabilities of periodic soft nanostructures and their interaction with the deformation of a base could lead to collective buckling. Our theoretical calculations suggest multiple modes of buckling associated with distinctive potential energies. This theoretical discovery allowed us to selectively promote certain buckling modes through experiments as an unusual approach for nanolithography. One typical example includes reducing the feature size in a selectively buckled grating from a pitch of 200 to 130 nm.
Family History Unawareness of Blood Clot Risk: Links to Misdiagnoses and Illness Uncertainties in Personal and Expert Realms

The difficulty of diagnosing blood clots makes salient the question, “What role does family history awareness have for guiding lay and expert actions?” The authors examine the in-depth life reflection interviews of 20 women who experienced a first venous blood clot between the ages of 18 and 50 years, identifying causal attributions the women made for thrombosis after the event. Twelve participants described an understanding of the cascade of events linked to thrombosis, revealing that there is seldom a single cause. The other eight identified belief in a single determining cause for their thrombosis. The authors reflect on the symptoms the women experienced during the course of the clotting event, patterns of care that they executed to self-manage their blood clot, and their misdiagnoses associated with symptoms and care. The women recalled the patterns of care received through formal health care systems and the reported misdiagnoses linked to these interactions. The recollections reveal that the subtle ...
Robust spectral unmixing for anomaly detection

This paper is concerned with a joint Bayesian formulation for determining the endmembers and abundances of hyperspectral images along with sparse outliers which can lead to estimation errors unless accounted for. We present an inference method that generalizes previous work and provides a MCMC estimate of the posterior distribution. The proposed method is compared empirically to state-of-theart algorithms, showing lower reconstruction and detection errors.
Real-Time Identification of Possible Contamination Sources Using Network Backtracking Methods

In case of contamination intrusion in water distribution systems, water quality sensor data can be used to determine the location and time of the contamination source. One approach to contamination source identification is finding the source location that minimizes the difference between modeled and measured water quality. However, this is an inherently ill-posed mathematical problem, due to the shortage of measurements compared to source parameters, and regularization methods are required to force identification of a unique solution. An alternative practical method is developed in this paper to identify all possible locations and times that explain contamination incidents detected by the water quality sensors. Since sensors cannot detect the quantitative concentration of a contaminant, this method only requires a binary sensor status over time. A particle backtracking algorithm is used to identify the water flow paths and travel times leading to each sensor measurement. Those locations and times that are...
Fine structure and histochemistry of the freshly extruded and hardened spermatophore of the spiny lobster, Panulirus interruptus.

Freshly extruded and hardened spermatophores of the spiny lobster, Panulirus interruptus, were compared using light and electron microscopy (EM). The spermatophore is composed of a sperm tube embedded in an acellular matrix. The sperm tube consists of tightly packed spherical cavities in an acellular material within which the sperm lie. The extruded spermatophore is white, soft, and sticky on all surfaces. The highly coiled sperm tube can be seen near the surface of the foot of the spermatophore, which is the side that will attach to the exoskeleton of the female. The opposite surface, the cap, will harden and darken after exposure to seawater. In the soft spermatophore, the matrix surrounding the sperm tube and extending from foot to cap is composed of small (2-μm) granules embedded in a loose weave of filaments. In the hardened spermatophore, the matrix is composed of small (4-μm) empty spheres. At the cap region the matrix darkens, and at the foot the granules dissolve to form a thick layer characterized by vertical striations. The structure of this spermatophore is compared to those spermatophores of other decapods that have been described at the EM level. The chemical composition and possible function(s) of the various components are discussed.
A user's commentary on Fiswidgets.

computing environment for neuroimaging data analysis that involves the construction of graphical interfaces for existing software packages and tools. Two independent groups are targeted as users of this software resource: developers of new software tools for neuroimaging data analysis and end users who use image processing software to analyze data for publication. This commentary provides a perspective on the strengths and weaknesses of the Fiswidgets software as perceived by users within my neuroimaging research laboratory. We have served as beta testers of the software for the past two years, and some of the Fiswidgets developers also provide computer system administration support for my laboratory. All fourteen members of the laboratory involved in neuroimaging studies use the software, which has been used to analyze the data for two published papers, and six papers currently in preparation or review. In general, we have found the claims made by Fissell et al. (2002) to be well supported. Particular strengths of the Fiswidgets environment are its ease of use, its flexibility and commitment to multiple analysis packages and tools, and its capacity to support automatic and iterative execution of a complex processing sequence. A significant factor in the adoption of any new neuroimaging software is the ease by which it can be used. One of the biggest advantages to the Fiswidgets environment is the rapid learning curve demonstrated by new users. A few hours of one-on-one training with another experienced user in the laboratory, coupled with access to a “how-to” manual generated for use within the laboratory, can provide a new user with enough knowledge to complete a set of basic processing steps for a single subject (e.g., image reconstruction, detrending, baseline normalization, etc.). This is made possible by the use of graphical interfaces to the underlying processing software; most users with only rudimentary Unix or command-scripting skills can operate very proficiently within a Windows-like environment. Additionally, it is possible to save and recall stored processing sequences via the
Characteristics of an Abnormal Type of Egg Shell

Abstract EGG shells of the type illustrated in Figure 1 have a large number of small spots which are more translucent than the rest of the shell and lend the egg a speckled appearance when candled. The candling appearance of these shells is distinctly different from that of the mottled shells described by Holst, Almquist and Lorenz (1932), as in the latter case the more translucent areas are much larger and more numerous. Another peculiarity of these abnormal shells is that, when tapped, they emit a musical clink like that obtained from a glass vessel, while normal shells give only a dull sound. Hence, these abnormal shells will be referred to for convenience as “glassy” shells. Glassy shells appear to be thinner and more fragile than normal shells. Since it is a common belief that glassy shells are highly porous, because of their peculiar appearance, they are usually placed in the . . .
A Multilevel Investigation of the Association between School Context and Adolescent Nonphysical Bullying

Although researchers have identified individual-level predictors of nonphysical bullying among children and youth, school-level predictors (i.e., characteristics of the school environment that influence bullying exposure) remain largely unstudied. Using data from a survey of 1,838 students in 21 Boston public high schools, we used multilevel modeling techniques to estimate the level of variation across schools in student reports of nonphysical bully victimization and identify school-level predictors of bullying. We found significant between school variation in youth reports of nonphysical bullying, with estimates ranging from 25-58%. We tested school-level indicators of academic performance, emotional well-being, and school safety. After controlling for individual-level covariates and demographic controls, the percent of students in the school who met with a mental health counselor was significantly associated with bullying (OR = 1.03, 95% CI = 1.01, 1.06). There was no significant association between school-level academic performance and perceptions of school safety on individual reports of bullying. Findings suggest that prevention and intervention programs may benefit from attending to the emotional well-being of students and support the importance of understanding the role of the school environment in shaping student experiences with bullying.
Interagency teams: A vehicle for service delivery reform

Human service delivery organizations often have great difficulty implementing new service delivery technologies. This study examines the extent to which interagency service delivery teams facilitate the implementation of a popular reform that significantly challenges the status quo: family-centered service delivery. Survey data from 121 providers representing 25 agencies within one county suggest that interagency teams may promote provider implementation of new service delivery practices. Teams members were more likely than nonteam members to implement practices consistent with family-centered service delivery. Consumer focus group data support these findings, with consumers noting that services received from providers in the team context were more individualized, empowering, and comprehensive than the services they typically received in the county. The implications of these findings for practitioners and scholars interested in facilitating human service delivery reform are discussed. © 2002 Wiley Periodicals, Inc.
Homotopic invariance of fixed points in hyperconvex metric spaces

Abstract We consider the homotopic invariance of fixed points of set-valued contractions and nonexpansive mappings in hyperconvex metric spaces. Results previously obtained only for Banach spaces are extended to the setting of these metric spaces.
The instability of blood pressure variability over time

Abstract The variability of blood pressure for the individual person is an important parameter in the design of screening programs for detecting persons with high blood pressure. The components of this variability have been assessed in a group of 326 persons in an industrial setting and a recommendation has been made that persons be screened for three visits with two measurements per visit in order to maximize the sensitivity and specificity of the procedure [1]. One question that arises is whether the variance components remain stable over time for a particular person. In order to answer this question, we rescreened 123 persons from the above group approximately 1 yr after the initial screening and estimated their variance components a second time. We find that in general there is no significant correlation between the variance components measured 1 yr apart. The validity of the concept of labile hypertension is discussed in light of these findings.
Validation of the System Usability Scale (SUS) SUS in the Wild

For almost 20 years, practitioners and researchers have been using the System Usability Scale (SUS) as a “quick and dirty” method of evaluating the usability of different websites, software, and ot...
Feminist theories and media studies

This essay discusses the assumptions that ground radical, liberal, and socialist feminist theoretical frameworks, and reviews and critiques feminist media research. I argue that liberal feminism, which characterizes much U.S. mainstream media research, speaks only to white, heterosexual, middle and upper class women and is incapable of addressing most women's concerns. Radical and structuralist feminist communication scholars, however, tend to focus exclusively on texts and often ignore important contextual considerations. I conclude that socialist feminism offers the greatest potential for a comprehensive framework to address women's devaluation in communication but that much more theoretical and empirical work still needs to be done. Finally, I encourage the recent tendency among feminist communication scholars to ignore disciplinary boundaries and draw freely on literary, film, and speech studies, as well as mass communication and feminist theory.
G-protein-coupled receptor family

Abstract The discovery of dozens of new sequences belonging to this superfamily, the increasing use of the polymerase chain reaction to isolate new genes, and the high-level expression of receptors in yeast are the highlights of recent research in this field.
An intrinsic potential‐dependent inactivation mechanism associated with calcium channels in guinea‐pig myocytes.

1. Currents through Ca2+ channels of single guinea-pig ventricular myocytes were studied using patch electrodes for whole-cell recording. Currents through Na+ and K+ channels were suppressed by the application of drugs or the substitution of impermeant ions. 2. Inactivation of the Ca2+ current (ICa) was investigated using a two-pulse protocol. The amount of inactivation left behind by a pre-pulse appeared to be related to current magnitude, as others have reported. The dependence of inactivation on the pre-pulse potential was partially U-shaped, as the amount of inactivation peaked at 0 mV and then declined with more positive pre-pulses. 3. Non-specific current carried by monovalent ions through Ca2+ channels (Ins) was induced by lowering the extracellular Ca2+ concentration with EGTA. Ins peaked in an inward direction at -20 mV, reversed direction at +22 mV, and became a large outward current at more positive potentials. 4. Ins inactivated with a slow time course. The inactivation was not due to accumulation or depletion phenomena. Studies using two-pulse protocols showed that the amount of inactivation left by a pre-pulse was directly related to the pre-pulse potential. 5. The addition of micromolar amounts of free Ca2+ to the external solution induced outward rectification of Ins. Inward currents were small or absent, while larger outward currents could still be seen at very positive potentials. Ca2+-channel inactivation still occurred under these conditions, even in the absence of any significant ionic movement. 6. The time courses of Ins inactivation and recovery were studied. The half-time of Ins inactivation decreased with larger depolarizations. Recovery of Ins was very slow, but could be accounted for by changes in the surface charge of the membrane. 7. It is concluded that Ins inactivation is due solely to a voltage-dependent inactivation process which is intrinsic to myocardial Ca2+ channels. Voltage-dependent inactivation appears to account for a significant proportion of total Ca2+-channel inactivation at negative potentials, and appears to account for almost all of the inactivation at very positive potentials, even in the presence of millimolar concentration of external Ca2+.
Arsenic, antimony, and germanium biogeochemistry in the Baltic Sea

Arsenic, antimony, and germanium species concentrations have been determined from fivehydrographic stations along the central axis of the Baltic Sea from the Bornholm Basin to theGulf of Finland. Arsenic and antimony concentrations are lower than in the open oceans and inmost rivers. In the oxic waters, the pentavalent species of As and Sb predominate, while in theanoxic basins, the distribution shifts to the trivalent species and possibly some sulfo-complexes.Methylated arsenic species make up a large fraction of dissolved As in the surface waters, andmethylated species of As, Sb, and Ge are detectable throughout the water column. Germanicacid concentrations are about ten times higher than in the ocean and much higher than can beaccounted for by Ruvial input. The vertical distributions of arsenic, antimony, and germaniumwithin the Baltic Sea are controlled by biogeochemical cycling, involving biogenic uptake,particulate scavenging and partial regeneration. A mass balance including river and atmosphericinputs, exchange with the Atlantic through the Belt Sea, and removal by sediment depositionsuggests that anthropogenic inputs make a significant contribution to the budgets of all threeelements, with atmospheric fluxes dominating the input of Ge to the Baltic. DOI: 10.1111/j.1600-0889.1984.tb00232.x
A Hydrophobic Gel Phantom for Study of Thermochemical Ablation: Initial Results Using a Weak Acid and Weak Base

Purpose To develop a model for study of exothermic chemical reactions potentially useful for tissue ablation. Materials and Methods Seven gelatins ranging from 0.5% to 30% wt/vol with and without 15% or 30% caps and several commercial gels were evaluated. Baseline temperature measurements were taken. Acetic acid and ammonium hydroxide were sequentially injected over periods of 10–15 seconds in 1-mL aliquots, forming a discrete aqueous reaction chamber. Congo red pH indicator was included to assess the reaction. A thermocouple allowed data collection at completion of injection and every 15 seconds for 5 minutes. Injections were performed in triplicate, and average temperatures for each time point were reported. Results Gelatins fractured or refluxed even at the lowest concentrations tested. Most commercial gels proved too viscous and likewise led to reflux along the needle tract. A mineral oil–based gel was selected because of its ability to form a chamber without reflux or fracture and its clear colorless character, hydrophobic nature, chemical stability, viscosity, specific gravity, and cost. Temperatures during the first 60 seconds of the neutralization reaction showed an immediate increase that correlated well with concentration. Conclusions The oil gel phantom is a safe, useful, readily available, inexpensive model to study mixing behaviors and maximum heating potentials for reactions that may prove useful in thermochemical tissue ablation for oncologic interventions. Measurable temperature changes occurred even at the lowest concentrations, and higher concentrations produced a greater release of heat energy.
Persistent expression of activated Notch inhibits corticotrope and melanotrope differentiation and results in dysfunction of the HPA axis

The hypothalamic-pituitary-adrenal (HPA) axis is an important regulator of energy balance, immune function and the body's response to stress. Signaling networks governing the initial specification of corticotropes, a major component of this axis, are not fully understood. Loss of function studies indicate that Notch signaling may be necessary to repress premature differentiation of corticotropes and to promote proliferation of pituitary progenitors. To elucidate whether Notch signaling must be suppressed in order for corticotrope differentiation to proceed and whether Notch signaling is sufficient to promote corticotrope proliferation, we examined the effects of persistent Notch expression in Pomc lineage cells. We show that constitutive activation of the Notch cascade inhibits the differentiation of both corticotropes and melanotropes and results in the suppression of transcription factors required for Pomc expression. Furthermore, persistent Notch signaling traps cells in the intermediate lobe of the pituitary in a progenitor state, but has no effect on pituitary proliferation. Undifferentiated cells are eliminated in the first two postnatal weeks in these mice, resulting in a modest increase in CRH expression in the paraventricular nucleus, hypoplastic adrenal glands and decreased stress-induced corticosterone levels. Taken together, these findings show that Notch signaling is sufficient to prevent corticotrope and melanotrope differentiation, resulting in dysregulation of the HPA axis.
Will Wage Setters Ever Stagger Decisions

Models featuring the implications of long-term contracts typically impose the pattern of negotiation and then develop the implications of this particular structure with no analysis of whether the structure is optimal or stable. Recent work, however, focuses on the choice of the timing of wage negotiations across sectors.1 In Fethke and Policano [1984] we develop a two-sector model in which each sector is subject to both aggregate and relative disturbances. The main result is that whenever the variability of relative disturbances exceeds the weighted variability of aggregate disturbances, a uniformly staggered pattern of negotiation represents a symmetric noncooperative Nash solution. The twosector case has special properties. First, the benefit associated with staggered negotiation apparently depends on the existence of large negotiating sectors in the economy. Second, symmetry of relative disturbances in the two-sector case leads to the unusual equivalence of the noncooperative and the joint-optimization solutions to the problem of determining the optimal negotiation pattern. One natural question concerns whether the incentive to stagger negotiation dates will diminish as the number of sectors increases. In this paper we develop the three-sector case in detail and then generalize the analysis to any number of sectors. The results indicate that the more significant are relative disturbances, the larger is the number of sectors that will be supported by a stable Nash equilibrium with uniformly staggered negotiation dates. In an economy characterized by atomistic sectors, the incentive to stagger negotiation dates disappears. We also compare the joint-optimization solution with the Nash solution and find that when there are more than two sectors, the requirement for uniform staggering to be optimal is more difficult to satisfy under joint optimization than under the Nash strategy. This di-
Chemical defense of the red tide dinoflagellate Karenia brevis against rotifer grazing

In order to test whether phytoplankton such as the red tide dinoflagellate Karenia brevis negatively affect rotifer grazers and what mechanisms are involved in these interactions, we conducted laboratory feeding experiments using K. brevis cultured from Gulf of Mexico coastal waters and two species of rotifers, one co-occurring and the other from an inland sea in Russia. The co-occurring rotifer Brachionus ibericus did not ingest K. brevis as a sole diet but tolerated K. brevis in a diet mixed with Rhodomonas lens, whereas the allopatric rotifer, Brachionus plicatilis, rejected K. brevis in either diet, although B. plicatilis started feeding on the mixed diet after a delay of 4 days. The deterrence of K. brevis was mediated by its cellular organic extracts and not by exudates, with compounds other than brevetoxins PbTx-2, PbTx-3, and PbTx-9 implicated in deterrence. The finding that closely related rotifers respond differently to K. brevis and to its chemical defense suggests that a shared evolutionary history may have led B. ibericus to tolerate K. brevis in a mixed diet.
Agronomic productivity and nitrogen requirements of alternative tillage and crop establishment systems for improved weed control in direct-seeded rice

a b s t r a c t Weed control is a primary concern in direct-seeded rice, particularly for herbicide-resistant weed species which stand to threaten the long-term sustainability of California rice systems. In a four-year field study we evaluated the potential for improved weed control using no-till stale seedbed practices in water- seeded (WS) and drill-seeded (DS) rice establishment systems. In addition, as the agronomic performance of alternative tillage and crop establishment methods is not well understood, we assessed the produc- tivity of these systems and estimated economic optimum nitrogen (EON) rates based on yield response to nitrogen (N) trials. Establishment system treatments included: water-seeded conventional tillage (WS conventional), water-seeded conventional tillage stale seedbed (WS stale), water-seeded no-till stale seedbed (WS no-till stale), drill-seeded conventional tillage (DS conventional), and drill-seeded no-till stale seedbed (DS no-till stale). Compared to the WS conventional system, WS stale and WS no-till stale treatments significantly reduced sedge weed biomass by 59 and 95%, respectively. Although redstem (Ammannia spp.) was not controlled, alternative WS systems reduced grass weed biomass by more than 99% when present. Within DS systems, no-till stale seedbed practices significantly reduced watergrass (Echinochloa spp.) biomass by 75% in the first two years but did not improve watergrass control during the second half of the study. Grain yields were not different for conventional and alternative rice establish- ment systems each year when N was applied at 168 kg N ha −1 and weeds were fully controlled. However, yields were significantly lower for alternative establishment systems compared to the WS conventional system when no N fertilizer was applied, likely as a result of greater soil N losses. The response of grain yield to N rate was significantly different among systems and estimated EON rates indicated that WS stale and WS no-till stale systems required an increase of 30-35 kg N ha −1 to maximize yields and returns to N compared to the WS conventional system. Results from this experiment demonstrate that alternative tillage and crop establishment systems can lead to improved weed control while remaining viable from an agronomic and economic standpoint in California. Provided N rates are close to optimal and WS and DS establishment methods are selected to target weed species of concern, these findings suggest that no-till stale seedbed practices should be considered as a component of integrated weed management strategies in direct-seeded rice moving forward.
Multicystic encephalomalacia after first-trimester intrauterine fetal death in monochorionic twins

Abstract Multicystic encephalomalacia occurs in approximately 20% of surviving cotwins after second- and third-trimester intrauterine fetal death of one twin in monochorionic pregnancies. We report a case of multicystic encephalomalacia after the demise of a cotwin in the first trimester diagnosed by magnetic resonance imaging and confiarmed pathologically.
Soleus and anterior tibial motor units of the cat

Abstract The functional properties of 30 soleus and 46 anterior tibial motor units in the cat were investigated by isolating and stimulating filaments of ventral rootlets containing one functional axon. The soleus data support previous studies which indicated slow conducting axons and slow contracting motor units for that muscle. Force output was greater than reported by others but consistent with the weight-beraing role of soleus in posture and locomotion. Anterior tibial units were supplied by fast conducting axons. Their contraction times were short, but average force output was similar to that of the soleus units. At low rates of stimulation soleus units developed substantially more tension than anterior tibial units. This finding provides additional evidence that tone can be developed and maintained in postural muscles by the asynchronous activation of slowly firing motor units. Within the populations of soleus or anterior tibial motor units there was no clear relation between axonal conduction velocity, contraction time or peak tetanic tension. A relationship among these parameters has been generally assumed for large as well as small muscles of the cat hind limb. The physiological properties of motor units reflect the individuality of muscle structure and function. The concept of motor unit types has been a useful one, yet the contractile properties of any one type may vary from muscle to muscle.
Individual variability in Tyr-Gly-Gly formation from enkephalin hydrolysis in mouse plasma

We examined the effects of captopril (an angiotensin-converting enzyme inhibitor) and phosphoramidon (a selective enkephalinase inhibitor) on Tyr-Gly-Gly production during Met-enkephalin hydrolysis in plasma samples taken from individual outbred Swiss-Webster and inbred C57BL/6J and DBA/2J mice. Discriminant analysis procedures identified three distinct plasma profiles of Tyr-Gly-Gly production in all strains of mice: a captopril-sensitive/phosphoramidon-insensitive profile, a captopril-insensitive/phosphoramidon-sensitive profile, and a moderate captopril and phosphoramidon sensitivity profile. The abilities of captopril and phosphoramidon to inhibit Tyr-Gly-Gly production in the same mouse plasma sample were highly inversely correlated (r = -0.938). Plasma of Swiss-Webster mice whose cages and bedding had been changed 24 h prior to sample collection was significantly more likely to exhibit the captopril-sensitive/phosphoramidon-insensitive profile than the plasma of mice whose cages/bedding had not been changed for at least 5 days. The results suggest that environmental novelty may dramatically alter the activity of a plasma dipeptidyl carboxypeptidase system, and thereby regulate behavioral and physiological responses to novel experiences.
FISHING YIELD, CURVATURE AND SPATIAL BEHAVIOR: IMPLICATIONS FOR MODELING MARINE RESERVES

. Given a paucity of empirical data, policymakers are forced to rely on modeling to assess potential impacts of creating marine reserves to manage fisheries. Many modeling studies of reserves conclude that fishing yield will increase (or decrease only modestly) after creating a reserve in a heavily exploited fishery. However, much of the marine reserves modeling ignores the spatial heterogeneity of fishing behavior. Contrary to empirical findings in fisheries science and economics, most models assume explicitly or implicitly that fishing effort is distributed uniformly over space. This paper demonstrates that by ignoring this heterogeneity, yield-per-recruit models systematically overstate the yield gains (or understate the losses) from creating a reserve in a heavily exploited fishery. Conversely, at very low levels of exploitation, models that ignore heterogeneous fishing effort overstate the fishing yield losses from creating a reserve. Starting with a standard yield-per-recruit model, the paper derives a yield surface that maps spatially differentiated fishing effort into total long-run fishing yield. It is the curvature of this surface that accounts for why the spatial distribution of fishing effort so greatly affects predicted changes from forming a reserve. The results apply generally to any model in which the long-run fishing yield has similar curvature to a two-patch Beverton-Holt model. A simulation of marine reserve formation in the California red sea urchin fishery with Beverton-Holt recruitment, eleven patches, and common larval pool dispersal dynamics reinforces these results.
The benefit of upgrading chronically right ventricle–paced heart failure patients to resynchronization therapy demonstrated by strain rate imaging

Background RV pacing induces conduction delay (CD), mechanical dyssynchrony, and increased morbidity in patients with HF. CRT improves HF symptoms and survival, but sparse data exist on its direct effect on chronically RV-paced HF patients. Objectives To assess the benefit of cardiac resynchronization therapy (CRT) in chronically right ventricle (RV)–paced heart failure (HF) patients. Methods We studied 12 consecutive patients with class III HF who had a previously implanted pacemaker or implantable cardioverter-defibrillator. These individuals were chronically RV paced and referred for upgrade to a biventricular device by their primary cardiologists. Tissue Doppler and strain rate imaging (TDI and SRI, respectively) were performed immediately before each upgrade and 4–6 weeks afterward to quantify changes in regional wall motion and synchrony with CRT. Results CRT significantly reduced the mean QRS duration (205 ms to 156 ms; P P P = .006). The parameter exhibiting greatest improvement was the coefficient of variation (CoV: standard deviation/mean) of time to peak systolic strain rate, a marker of ventricular dyssynchrony, which decreased from 34.3%±13.0% to 19.0%±6.6% ( P P Conclusions Upgrading chronically RV-paced HF patients to CRT improves global and regional systolic function. TDI and SRI provide compelling evidence that this benefit parallels that seen in HF patients with CD unrelated to RV pacing, which implies that biventricular pacing synchronizes mechanical activation in different myocardial regions in patients upgraded from RV pacing as well.
Rise, decline, fall

In the international system of states, wonders are occurring. As the bipolar structure wrought during and after World War II by the Soviet Union, the United States, and their allies has begun to crack, student of international relations have renewed their interest in long-term historical studies of states and state systems. Among other changes, scholars have started defecting from the assumption that the nuclear era is unique, hence not worth comparing with other eras. They (or perhaps I should say we) have begun taking seriously the search for connections and disjunctions between the Europecentered system of states that ruled that world before 1945 and the successive international regimes that have prevailed since then. We have entered a period of fruitful divergence among views of how states change form, how relations among states evolve, and connections between the two. We are, in fact, seeing increasingly that the two processes are one: that the same interactions-centered on war, preparations for war, and threats of wartransform states and systems of states. Michael Doyle's Empires illustrates the renewed will to unite analyses of international and domestic politics. It takes a very different tack from
Edge enhancement by diffusion: microscopic magnetic resonance imaging of an ultrathin glass capillary

Abstract Diffusion can improve magnetic resonance imaging (MRI) on a microscopic length scale by edge enhancement which acts against diffusional blurring. We demonstrate the edge-enhancement effect and we provide an appropriate mathematical description using Kubo's line shape function formalism. We apply the theory to make specific predictions for edge enhancement in a two-dimensional phantom system. In particular, we determine the corresponding line shape function and use it to reconstruct an MRI image of water in an ultrathin (50 μm) capillary tube. We explain how a corresponding experiment can be realized with microcoils capable of receiving adequate free induction decay signals from microscopically small sample volumes.
Secreted β-APP stimulates MAP kinase and phosphorylation of tau in neurons

Abstract We have previously demonstrated that the secreted form of the β-amyloid precursor protein (β-APP) activates mitogen-activated protein (MAP) kinases in PC-12 pheochromocytoma cells. β-APP as well as other treatments that activate MAP kinase also enhance phosphorylation of the microtubule-associated protein tau in these cells. In this study, we extended this analysis to neurons. Using dissociated cultures of cortical neurons, we found that exposure to β-APP activated MAP kinase 4 and 7 days but not 1 day after plating. Phosphorylation of tau in neurons was measured by immunoreactivity with the AT8 antibody, which recognizes a phosphorylated epitope present in tau from paired helical filaments. We found that activation of MAP kinase in neurons was associated with increased amounts of AT8-reactive tau. These results support a role for MAP kinase in transducing the biological effects of secreted β-APP on neurons and suggest possible mechanisms by which β-APP might be involved in the pathogenesis of Alzheimer's disease.
A Reordering for the PageRank Problem

We describe a reordering particularly suited to the PageRank problem, which reduces the computation of the PageRank vector to that of solving a much smaller system and then using forward substitution to get the full solution vector. We compare the theoretical rates of convergence of the original PageRank algorithm to that of the new reordered PageRank algorithm, showing that the new algorithm can do no worse than the original algorithm. We present results of an experimental comparison on five datasets, which demonstrate that the reordered PageRank algorithm can provide a speedup of as much as a factor of 6. We also note potential additional benefits that result from the proposed reordering.
Coccidioidomycosis in adolescents presenting as chest pain

Chest pain is a relatively common complaint in adolescents and is most often attributed to anxiety or musculoskeletal conditions. Pleuritic chest pain in association with fever and cough are frequently reported in adults with primary pulmonary coccidioidomycosis. We describe three cases in which chest pain mimicking costochondritis was the predominant initial presenting symptom of pulmonary coccidioidomycosis. In addition, in each case, recent tuberculin skin test reactivity complicated the diagnostic assessment and treatment. We conclude that, in endemic areas, coccidioidomycosis should be considered in the differential diagnosis of acute chest pain in teenagers as well as in adults.
Environmental pollutants, diet, physical activity, body size, and breast cancer: where do we stand in research to identify opportunities for prevention?

Department of Preventive Medicine, Keck School of Medicine,University of Southern California, Los Angeles, California.Breast cancer is the most common invasive cancer in women worldwide and theleading cause of death in US women in mid-life. Treatment has adverse effects,adding to the importance of finding modifiable risk factors. At the invitation ofSusan G. Komen for the Cure, we reviewed studies of breast cancer and environ-mental pollutants, diet (assessed prospectively), body size, and physical activity,and animal studies that identify chemicals as potential mammary carcinogens.Databases developed in the review include information on 216 chemicals thatincreased mammary gland tumors in animal studies and 450 epidemiologic stu-dies (accessible at www.silentspring.org/sciencereview and www.komen.org/environment). Exposure to potential mammary carcinogens is widespread fromchemicals found in consumer products, air and drinking water pollution, food,and women’s workplaces. Epidemiologic studies have included only a small num-ber of chemicals identified as mammary carcinogens or as hormone disruptors,which may have implications for breast cancer; however, evidence is emergingfor associations between breast cancer and polychlorinated biphenyls, polycyclicaromatic hydrocarbons, and organic solvents. Prospective diet studies have notrevealed consistent associations with breast cancer. Improved exposure assess-ment methods will help advance future human studies of both diet and environ-mental pollutants. Studies of physical activity show that it is protective. In thesame vein as evidence-based medicine, messages for patients, policymakers, andReceived July 18, 2006; revision receivedJanuary 3, 2007; accepted January 30, 2007.Supported by Susan G. Komen for the Cure aspart of the Environmental Factors and Breast Can-cer Science Review project led by Silent SpringInstitute with collaborating investigators at Har-vard Medical School, Roswell Park Cancer Insti-tute, and the University of Southern California.We thank Wendy Mason and Dwight E. Randle atSusan G. Komen for the Cure, for their leadershipthroughout the project. We thank Liesel Seryakfor expert research assistance in preparation ofthis commentary.Address for reprints: Julia Green Brody, PhD,Silent Spring Institute, 29 Crafts St., Newton, MA02458; Fax: (617) 332-4284; E-mail: brody@silentspring.org
Line widths and temperatures of Ar-N2 ICP discharges measured by high-resolution Fourier transform spectrometry

Abstract The high-resolution Fourier transform spectrometer (FTS) of the Los Alamos National Laboratory was used for diagnostic studies of Ar-N 2 ICP discharges. High-resolution FTS data were obtained to: (a) conduct analysis of line widths and line shapes for Fe lines to ascertain contributions from the Gaussian and Lorentzian components; (b) to calculate the Doppler or translational temperatures of emitting species by using the half width of the Gaussian component; and (c) to determine excitation temperatures based on the relative intensities of many spectral lines. The effect of gas composition and plasma operating conditions on line widths, Doppler and excitation temperatures were examined.
The Wallerian degeneration slow (Wlds) gene does not attenuate disease in a mouse model of spinal muscular atrophy

Spinal muscular atrophy (SMA) is a severe neuromuscular disease characterized by loss of spinal alpha-motor neurons, resulting in the paralysis of skeletal muscle. SMA is caused by deficiency of survival motor neuron (SMN) protein levels. Recent evidence has highlighted an axon-specific role for SMN protein, raising the possibility that axon degeneration may be an early event in SMA pathogenesis. The Wallerian degeneration slow (Wld(s)) gene is a spontaneous dominant mutation in mice that delays axon degeneration by approximately 2-3 weeks. We set out to examine the effect of Wld(s) on the phenotype of a mouse model of SMA. We found that Wld(s) does not alter the SMA phenotype, indicating that Wallerian degeneration does not directly contribute to the pathogenesis of SMA development.
Identification of Variables Associated With Group Separation in Descriptive Discriminant Analysis: Comparison of Methods for Interpreting Structure Coefficients

Discriminant Analysis (DA) is a tool commonly used for differentiating among 2 or more groups based on 2 or more predictor variables. DA works by finding 1 or more linear combinations of the predic...
An epitaxial-base Germanium power transistor for television horizontal deflection

The evolution of a transistor designed specifically for television horizontal deflection is described in this paper. Device requirements are discussed and the required device design compromises are listed. The technique of epitaxy is indicated as a means of avoiding some of the usual device design compromises. The characteristics of the resulting epitaxial transistor are given. A few circuit design considerations are discussed.
Bmp Signaling Regulates Myocardial Differentiation from Cardiac Progenitors Through a MicroRNA-Mediated Mechanism

MicroRNAs (miRNAs) are small, noncoding RNAs that regulate gene expression posttranscriptionally. We investigated the hypothesis that bone morphogenetic protein (Bmp) signaling regulates miRNAs in cardiac progenitor cells. Bmp2 and Bmp4 regulate OFT myocardial differentiation via regulation of the miRNA-17-92 cluster. In Bmp mutant embryos, myocardial differentiation was delayed, and multiple miRNAs encoded by miRNA-17-92 were reduced. We uncovered functional miRNA-17-92 seed sequences within the 3' UTR of cardiac progenitor genes such as Isl1 and Tbx1. In both Bmp and miRNA-17-92 mutant embryos, Isl1 and Tbx1 expression failed to be correctly downregulated. Transfection experiments indicated that miRNA-17 and miRNA-20a directly repressed Isl1 and Tbx1. Genetic interaction studies uncovered a synergistic interaction between miRNA-17-92 cluster and Bmp4, providing direct in vivo evidence for the Bmp-miRNA-17-92 regulatory pathway. Our findings indicate that Bmp signaling directly regulates a miRNA-mediated effector mechanism that downregulates cardiac progenitor genes and enhances myocardial differentiation.
Regioselective cycloaddition of a C-alkoxy-nitrone

Abstract The first cycloaddition of a C-alkoxy-nitrone is reported and is regiospecific, yielding only the 4-substituted adduct with methyl propiolate as predicted by frontier orbital theory.
Prenatal antidepressant exposure is associated with risk for attention-deficit hyperactivity disorder but not autism spectrum disorder in a large health system

Prenatal antidepressant exposure is associated with risk for attention-deficit hyperactivity disorder but not autism spectrum disorder in a large health system
Factors controlling evaporation and energy partitioning beneath a deciduous forest over an annual cycle.

Abstract The energy balance components were measured above the ground surface of a temperate deciduous forest over an annual cycle using the eddy covariance technique. Over a year, the net radiation at the forest floor was 21.5% of that above the canopy, but this proportion was not constant, primarily because of the distinct phenological stages separated by the emergence and senescence of leaves. The dominant response to seasonal changes in net radiation was through corresponding changes in the sensible heat flux, and both net radiation and sensible heat flux peaked just before leaf emergence. Evaporation at the forest floor was typically less than 0.5 mm per day, and unlike sensible heat flux, was not closely coupled to seasonal changes in net radiation. Instead, evaporation at the forest floor responded primarily to rapid changes in litter water content. Forest floor evaporation was limited by the water-holding capacity of litter, and when the atmospheric demand was large, the litter layer dried on the time scale of several hours. After this rapid period of drying, net radiation and sensible heat flux dominated the energy budget. When leaves were present during the growing season, the sensible and latent energy fluxes at the forest floor were less than 10% of the total canopy fluxes, and the mean Bowen ratio was similar to that above the canopy. However, during the dormant season, the controls of the energy budget at the forest floor largely determine the whole canopy fluxes. On an annual basis, the fluxes from the forest floor are roughly 15–22% of those above the canopy and the evaporation was 86 mm.
Transplantation of neurons reveals processing areas and rules for synaptic connectivity in the cricket nervous system

In order to assess the nature of spatial cues in determining the characteristic projection sites of sensory neurons in the CNS, we have transplanted sensory neurons of the cricket Acheta domesticus to ectopic locations. Thoracic campaniform sensilla (CS) function as proprioceptors and project to an intermediate layer of neuropil in thoracic ganglia while cercal CS transduce tactile information and project into a ventral layer in the terminal abdominal ganglion (TAG). When transplanted to ectopic locations, these afferents retain their modality-specific projection in the host ganglion and terminate in the layer of neuropil homologous to that of their ganglion of origin. Thus, thoracic CS neurons project to intermediate neuropil when transplanted to the abdomen and cercal CS neurons project to a ventral layer of neuropil when transplanted to the thorax. We conclude that CS can be separated into two classes based on their characteristic axonal projections within each segmental ganglion. We also found that the sensory neurons innervating tactile hairs project to ventral neuropil in any ganglion they encounter after transplantation. Ectopic sensory neurons can form functional synaptic connections with identified interneurons located within the host ganglia. The new contacts formed by these ectopic sensory neurons can be with normal targets, which arborize within the same layer of neuropil in each segmental ganglion, or with novel targets, which lack dendrites in the normal ganglion and are thus normally unavailable for synaptogenesis. These observations suggest that a limited set of molecular markers are utilized for cell-cell recognition in each segmentally homologous ganglion. Regenerating sensory neurons can recognize novel postsynaptic neurons if they have dendrites in the appropriate layer of neuropil. We suggest that spatial constraints produced by the segmentation and the modality-specific layering of the nervous system have a pivotal role in determining synaptic specificity.