cssi/SciSciGPT-SciSciNet huggingface dataset:
Entropic effects in large-scale Monte Carlo simulations

The efficiency of Monte Carlo samplers is dictated not only by energetic effects, such as large barriers, but also by entropic effects that are due to the sheer volume that is sampled. The latter effects appear in the form of an entropic mismatch or divergence between the direct and reverse trial moves. We provide lower and upper bounds for the average acceptance probability in terms of the Renyi divergence of order 1/2 . We show that the asymptotic finitude of the entropic divergence is the necessary and sufficient condition for nonvanishing acceptance probabilities in the limit of large dimension. Furthermore, we demonstrate that the upper bound is reasonably tight by showing that the exponent is asymptotically exact for systems made up of a large number of independent and identically distributed subsystems. For the last statement, we provide an alternative proof that relies on the reformulation of the acceptance probability as a large deviation problem. The reformulation also leads to a class of low-variance estimators for strongly asymmetric distributions. We show that the entropy divergence causes a decay in the average displacements with the number of dimensions n that are simultaneously updated. For systems that have a well-defined thermodynamic limit, the decay is demonstrated to be n(-1/2) for random-walk Monte Carlo and n(-1/6) for smart Monte Carlo (SMC). Numerical simulations of the Lennard-Jones 38 (LJ(38)) cluster show that SMC is virtually as efficient as the Markov chain implementation of the Gibbs sampler, which is normally utilized for Lennard-Jones clusters. An application of the entropic inequalities to the parallel tempering method demonstrates that the number of replicas increases as the square root of the heat capacity of the system.
Pulmonary growth and remodeling in infants with high-risk congenital diaphragmatic hernia.

Infants born with congenital diaphragmatic hernia (CDH) have pulmonary hypoplasia, but the pattern of postnatal growth in these lungs has not been documented. The lungs of 21 children dying with CDH were analyzed to determine how the pulmonary morphology changed with age. The patients were stratified into three age groups for ANOVA analysis (less than 8 days, 8 to 21 days, greater than 21 days). Morphometric techniques previously described were used. Lung volume and weight as well as pulmonary artery length and diameter increased with age (P = .04), whereas the number of airway generations was similar for each group. Radial alveolar number also increased, particularly in the contralateral lung (P = .02). The percentage of intraacinar artery muscularization decreased with age (P = .02), while larger intraacinar arteries showed a nonmuscular structure, again particularly in the contralateral lung (P = .004). It is concluded that: (1) significant lung growth does occur postnatally at the alveolar level after CDH repair; and (2) there is postnatal vascular remodelling resulting in larger and less muscular arteries. These changes should contribute to a decrease in pulmonary arterial hypertension over time. However, the time period over which these changes occur exceeds the current limitations of invasive support measures such as extracorporeal membrane oxygenation. Elucidation of the factors responsible for this growth could result in new therapeutic strategies to enhance or accelerate postnatal pulmonary development in infants with CDH.
Chromatin dynamics: Interplay between remodeling enzymes and histone modifications

Chromatin dynamics play an essential role in regulating the accessibility of genomic DNA for a variety of nuclear processes, including gene transcription and DNA repair. The posttranslational modification of the core histones and the action of ATP-dependent chromatin remodeling enzymes represent two primary mechanisms by which chromatin dynamics are controlled and linked to nuclear events. Although there are examples in which a histone modification or a remodeling enzyme may be sufficient to drive a chromatin transition, these mechanisms typically work in concert to integrate regulatory inputs, leading to a coordinated alteration in chromatin structure and function. Indeed, site-specific histone modifications can facilitate the recruitment of chromatin remodeling enzymes to particular genomic regions, or they can regulate the efficiency or the outcome of a chromatin remodeling reaction. Conversely, chromatin remodeling enzymes can also influence, and sometimes directly modulate, the modification state of histones. These functional interactions are generally complex, frequently transient, and often require the association of myriad additional factors. This article is part of a Special Issue entitled: Molecular mechanisms of histone modification function.
Whisker alignment of Ti–6Al–4V/TiB composites during deformation by transformation superplasticity

Abstract We examine the effect of 10 vol.% TiB whisker reinforcement on transformation superplasticity of Ti–6Al–4V, induced by thermal cycling about the α/β phase transformation range of the matrix under a uniaxial tensile stress. During superplastic deformation, the whiskers gradually align along the external loading axis, as measured by electron back-scattering diffraction of deformed specimens. The composites exhibit a gradual decrease in effective deformation rate during superplastic elongation. This effect is attributed to increased load transfer from matrix to whisker upon whisker alignment, and is explained with elastic calculations of stress partitioning.
Effect of spironolactone-hydrochlorothiazide on lung function in infants with chronic bronchopulmonary dysplasia

To test the hypothesis that spironolactone-hydrochlorothiazide (Aldactazide) will improve urine output and lung function in infants with bronchopulmonary dysplasia, we studied 21 hospitalized, spontaneously breathing, oxygen-dependent infants with chronic bronchopulmonary dysplasia. Infants were randomly assigned to receive either a 1:1 mixture of spironolactone and hydrochlorothiazide orally (n = 12) (3 mg/kg/day of both compounds) or no treatment (n = 9) for 6 to 8 days each. Dynamic lung compliance, total pulmonary resistance, and hemoglobin oxygen saturation were measured on the first and last days of each study period. Fluid intake and urine output were measured each day. Although the treatment significantly increased urine output, neither lung mechanics nor oxygenation were improved by the drug. The magnitude of the diuresis achieved with spironolactone-hydrochlorothiazide treatment was comparable to the diuresis achieved in a previous study of furosemide treatment (J Pediatr 1986:109;1034-9). Statistical analysis indicated that a type II error was an unlikely explanation for our failure to detect a beneficial effect. In three patients, doubling the oral dose did not improve lung mechanics or oxygenation. We speculate that diuresis per se is not responsible for lung function improvement during treatment with other drugs with diuretic properties.
Serotonin storage mechanism and its interaction with reserpine.

Es gelang nicht, mit physikalisch-chemischen Methoden einen HT-Komplex in hamolysierten oder homogenisierten Suspensionen von Kaninchen-Thrombozyten nachzuweisen. Versuchsergebnisse uber die HT-Aufnahme durch Thrombozyten stimmen mit der Moglichkeit uberein, dass das Amin in den Zellen durch einen aktiven Transportmechanismus konzentriert wird. Es wird angenommen, dass die Abgabe von normalem HT aus der Zelle unter Reserpineinwirkung, durch eine Hemmung des Aufnahmemechanismus und langsame, passive Diffusion aus den Zellen erfolgt.
Interpretation of crayfish hepatopancreatic function based on fine structural analysis of epithelial cell lines and muscle network.

The ultrastructure of R-, F-, and B-cells and of the myoepithelial network in crayfish hepatopancreas tubules was studied as a basis for the functional interpretation of hepatopancreatic digestive activity: 1. R-cells absorb luminal nutrients, mainly via contact digestion and molecular transport, and they store and metabolize glycogen and lipids. To this extent, R-cells combine the functions of vertebrate intestinal absorptive and hepatic parenchymal cells. 2. F-cells synthesize digestive enzymes and sequester them in a supranuclear vacuole which enlarges by pinocytic intake of luminal nutrients and fluids. 3. F-cell to B-cell transformation results from continued engorgement of the F-cell's supranuclear vacuole until only the nuclear region and a pinocytically activeapical complex remain identifiable. 4. B-cell secretion involves pinching off of the apical complex followed by extrusion of the enzyme-rich vacuolar contents. 5. The tubule's myoepithelial network consists of circular fibers, each containing a single myofibril, which branch to form longitudinal fibers. Sarcomeres are long (10–12 μ) and each thick myofilament is surrounded by 11–13 thin ones. This arrangement permits coordinated, tonic contractions of tubule segments which transport nutrients “in” and enzymes “out”. 6. Neurosecretory control of tubular function is suggested by the presence of vesicle-containing, extratubular cell processes which contact the circular muscle fibers.
Metal-mediated crystallization of amorphous germanium in germanium-silver layered systems

Abstract The crystallization behaviour of amorphous Ge (a-Ge) in a-Ge/Ag/a-Ge trilayer and a-Ge/Ag multilayer systems has been investigated using in situ transmission electron microscopy (TEM) and differential scanning calorimetry. The crystallization temperature of a-Ge in these systems is 240–270°C, about 250°C lower than that found in pure a-Ge. During the reaction, in situ cross-section TEM showed that Ag grains separate the a-Ge matrix and the crystallized Ge (c-Ge) grains, and that the Ag grains migrate towards the a-Ge region, leaving the c-Ge phase behind. Our in situ atomic resolution TEM also revealed that the lattice points of the migrating Ag grains are stationary. These observations indicate that the Ge atoms diffuse through the Ag grains for the growth of the c-Ge phase, whereas the migration of the Ag grains is caused by the reverse self-diffusion of the Ag atoms. The mechanism is essentially identical to that in other metal-mediated crystallization reactions (e.g. Al-Si, Ag-Si). The observ...
Exploding a few myths about productivity and presenting a formula for the future

There is ample evidence that in the past 17 years annual gains in productivity in the United States have lagged behind those of other advanced industrialized countries. Between 1960 and 1977, the U.S. could boast productivity increases of only 2.8 percent per year, compared with 5.7 percent for West Germany and 8.4 percent for Japan (Fig. 1). However, it should also be emphasized that the absolute productivity level in the U.S. is still high compared with other countries, even though the rate of improvement may be lower.
Innovation without imagination

There have been increasing calls within the evolutionary biology community for a new evolutionary synthesis, a new perspective on the mechanisms and processes that produce the remarkable diversity of life. The causes of evolutionary innovations, from the surge of animal diversity during the Cambrian radiation 530 million years ago to the explosion of placental mammals or the origin of flowering plants, appear to many to require explanations beyond those provided by the microevolutionary perspective of the Modern Synthesis.
Reactions of CH3SH and (CH3)2S2 on the (0001) and (0001̄) Surfaces of ZnO

Temperature-programmed desorption (TPD) was used to study the adsorption and reaction of CH3SH and (CH3)2S2 on the (0001) and (0001) surfaces of ZnO. The interaction of these molecules with ZnO was found to be structure-sensitive. Both CH3SH and (CH3)2S2 adsorb dissociatively on ZnO(0001), forming adsorbed methylthiolate intermediates and only molecularly on ZnO(0001). In the case of CH3SH, this result is consistent with that reported previously for the interaction of Bronsted acids with ZnO and indicates that exposed cation−anion pairs are the active sites for dissociative adsorption. Only exposed Zn cations are required for the dissociative adsorption of (CH3)2S2. Methylthiolate species produced by dissociative adsorption of CH3SH and (CH3)2S2 on ZnO(0001) were found to undergo a variety of reaction pathways, including coupling to produce dimethyl sulfide and oxidation to formaldehyde, CO, and CO2. Pathways for the production of these various products are proposed.
Piggyback sampler for dissolved gas studies on sealed water samples

Abstract A sampler which obtains leak-proof sealed water samples from any depth has been developed for the study of dissolved gases. Closing of the sampler is activated by the tripping of the Nansen bottle to which it is attached. The water collected by the sampler is thus taken at the same time and place at which the Nansen bottle measures thermometric depth and temperature and collects water for measurement of salinity and other properties. Other advantages include ease of operation and low cost. The sampler has been tested at sea under a wide range of conditions.
Expanding the boundaries of agricultural development

The challenges of reducing global hunger and poverty are different today than they were 30 years ago. Current challenges include price volatility associated with increased integration of food, energy, and finance markets; the steady progression of climate change; poorly defined land institutions; and a failure to break vicious cycles of malnutrition and infectious disease. Farmland speculation is occurring globally—often at odds with rural poverty alleviation—and food insecurity remains a pressing issue with the estimated number of chronically malnourished people hovering around one billion. Given these patterns, food and agriculture are becoming increasingly ingrained in international security and policy discussions. This paper explores several ways in which the traditional field of agricultural development needs to expand to address the broader issues of international security and human welfare. It focuses on five key interrelated issues: the macroeconomic and energy contexts of agricultural development; climate change; deforestation, land access, and land markets; farming systems and technology for the ultra-poor; and food-health linkages with a specific focus on infectious disease. Recommendations for investments in capacity building, revised curricula, and development projects are made on the basis of evidence presented for each issue. It is clear that academic programs, government agencies, development and aid organizations, and foundations need to dismantle the walls between disciplinary and programmatic fields, and to find new, innovative ways to reach real-world solutions.
Dynamic hardware-assisted software-controlled page placement to manage capacity allocation and sharing within large caches

In future multi-cores, large amounts of delay and power will be spent accessing data in large L2/L3 caches. It has been recently shown that OS-based page coloring allows a non-uniform cache architecture (NUCA) to provide low latencies and not be hindered by complex data search mechanisms. In this work, we extend that concept with mechanisms that dynamically move data within caches. The key innovation is the use of a shadow address space to allow hardware control of data placement in the L2 cache while being largely transparent to the user application and off-chip world. These mechanisms allow the hardware and OS to dynamically manage cache capacity per thread as well as optimize placement of data shared by multiple threads. We show an average IPC improvement of 10-20% for multi-programmed workloads with capacity allocation policies and an average IPC improvement of 8% for multi-threaded workloads with policies for shared page placement.
Proximity effect coupled V Cr superlattices

Abstract V m Cr n superlattices, where m and n denote the number of atomic planes of V and Cr in each layer, with m equal to 98, 147, 175 and 197 and n varying between 3 and 100 have been prepared. The films were grown in an ultra-high vacuum chamber (base pressure ≈1×10 −9 Torr) equipped with dual e-guns and a rotating substrate holder. Films were grown at 250°C on “c” cut sapphire substrates. The zero field transition temperature and parallel upper critical field of the films have been measured. A dimensional crossover in the parallel upper critical field is observed at n equal to about 80. The zero field transition temperature data has been modeled using the procedures and of Werthamer and Auvil and Ketterson. The magnetic scattering time, τ, in the Cr layers has been found to be dependent on the vacuum during deposition: 4.5×10 −14 sec for films deposited at ≤ 4×10 −7 Torr and 5.5×10 −14 sec for films deposited at ≤ 4×10 −8 Torr. For the V 175 Cr x series with n >- 80 the best fits occur for infinite scattering time τ.
A field-based technique for the longitudinal profiling of ultrarelativistic electron or positron bunches down to lengths of /spl les/10 microns

Present and future generations of particle accelerating and storage machines are expected to develop ever-decreasing electron/positron bunch lengths, down to 100 /spl mu/ and beyond. In this paper a method for measuring the longitudinal profiles of ultrashort (1000 /spl muspl ap/10 /spl mu/) bunches, based on: 1) the extreme field compaction attained by ultrarelativistic particles, and 2) the reduction of the group velocity of a visible light pulse in a suitably-chosen dielectric medium, is outlined. >
Senator Barack Obama: The Rhetoric of Hope and the American Dream

This article offers a brief discussion of the origin of Senator Barack Obama's rhetoric of hope. Specifically, it discusses how Senator Obama creates a contemporary vision of an inclusive America a...
Everyday executive functions in Down syndrome from early childhood to young adulthood: evidence for both unique and shared characteristics compared to youth with sex chromosome trisomy (XXX and XXY)

Executive functions (EF) are thought to be impaired in Down syndrome (DS) and sex chromosome trisomy (Klinefelter and Trisomy X syndromes; +1X). However, the syndromic specificity and developmental trajectories associated with EF difficulties in these groups are poorly understood. The current investigation (a) compared everyday EF difficulties in youth with DS, +1X, and typical development (TD); and (b) examined relations between age and EF difficulties in these two groups and a TD control group cross-sectionally. Study 1 investigated the syndromic specificity of EF profiles on the Behavior Rating Inventory of Executive Function (BRIEF) in DS (n = 30), +1X (n = 30), and a TD group (n = 30), ages 5-18 years. Study 2 examined age effects on EF in the same cross-sectional sample of participants included in Study 1. Study 3 sought to replicate Study 2's findings for DS by examining age-EF relations in a large independent sample of youth with DS (n = 85) and TD (n = 43), ages 4-24 years. Study 1 found evidence for both unique and shared EF impairments for the DS and +1X groups. Most notably, youth with +1X had relatively uniform EF impairments on the BRIEF scales, while the DS group showed an uneven BRIEF profile with relative strengths and weaknesses. Studies 2 and 3 provided support for fairly similar age-EF relations in the DS and TD groups. In contrast, for the +1X group, findings were mixed; 6 BRIEF scales showed similar age-EF relations to the TD group and 2 showed greater EF difficulties at older ages for +1X. These findings will be discussed within the context of efforts to identify syndrome specific cognitive-behavioral profiles for youth with different genetic syndromes in order to inform basic science investigations into the etiology of EF difficulties in these groups and to develop treatment approaches that are tailored to the needs of these groups.
Thermophysical properties of CeB6 and PrB6 at subambient temperatures

Equilibrium adiabatic heat-capacity measurements have been made on zone refined samples of CeB6 and PrB6. Companion measurements made on LaB6, NdB6, and GdB6 have been reported elsewhere. These show cooperative lambda-type anomalies associated with antiferro-magnetic ordering. Except for lanthanum hexaboride, Schottky internal crystal field levels result in significant contributions to the thermodynamic functions. The gross thermodynamic properties at 298.15 K heat capacity (Cp/R), entropy increment ( 0 0 , / m T SR ), and Gibbs energy function are correlated with the nature of the lanthanide. For LaB6, CeB6, PrB6, NdB6, and GdB6 the three properties are, respectively: {11.654, 12.014, 11.997, 11.916, 11.695} Cp/R; {10.001, 11.803, 12.430, 12.558, 13.982} S 0 /R, and finally {4.379, 5.912, 6.232, 6.451, 7.905} m 0 /R.
Direct generation of Spice compatible passive reduced order models of ground/power planes

The continuing growth of complexity in modern ULSI design, combined with sub-nanosecond switching speeds, have made necessary the careful assessment of issues such as interplane capacitance, decoupling capacitor selection and placement, as well as resonance effects in the power distribution network. Toward this objective, various research groups have proposed modeling methodologies based on a two-dimensional approximation of Maxwell's equations in the space between adjacent power/ground planes. In this paper, a solid power/ground plane pair is discretized by a distributed RLCG circuit. The resulting discrete model is used in conjunction with the passive reduced-order modeling algorithm PRIMA for the generation of low order, multi-port macromodels to be incorporated in non-linear circuit simulators such as SPICE. Through a rigorous mathematical and physical investigation of the distributed electromagnetic effects between power/ground planes, reliable estimates for the order of the reduced model are derived for accurate multiport modeling over a given frequency bandwidth. The numerical results show that the generated rules provide the robustness required for the numerical generation of guaranteed-passive, reduced order electrical models for power/ground plane structures of optimum complexity.
Unsupervised Speaker Diarization Using Riemannian Manifold Clustering

We address the problem of speaker clustering for robust unsupervised speaker diarization. We model each speakerhomogeneous segment as one single full multivariate Gaussian probability density function (pdf) and take into consideration the Riemannian property of Gaussian pdfs. By assuming that segments from different speakers lie on different (possibly intersected) sub-manifolds of the manifold of Gaussian pdfs, we formulate the original problem as a Riemannian manifold clustering problem. To apply the computationally simple Riemannian locally linear embedding (LLE) algorithm, we impose a constraint on the length of each segment so as to ensure the fitness of single-Gaussian modeling and to increase the chance that all k-nearest neighbors of a pdf are from the same submanifold (speaker). Experiments on the microphone-recorded conversational interviews from NIST 2010 speaker recognition evaluation set demonstrate promising results of less than 1%
Effects of Thromboxane Synthase Inhibition on Placental Prostacyclin and Thromboxane Production

Selective inhibition of thromboxane synthesis without affecting prostacyclin synthesis is being considered as a potential treatment for preeclampsia because of its imbalance of increased thromboxane/decreased prostacyclin production. Thromboxane production by the placenta is greatly increased in preeclampsia so effective therapy must inhibit placental, as well as maternal platelet, thromboxane production. The following study was done to evaluate the production rates of thromboxane and prostacyclin in placental tissues incubated with and without the throraboxane synthase inhibitor, U-63,557A. Fresh, human term placental tissues (350 mg) were incubated in a sterile manner in 7 ml Dulbecco's Modified Eagle's Medium for 48 hours at 37°C with 95% oxygen and 5% carbon dioxide in a metabolic shaker. Samples were collected at 0, 8, 20, 32 and 48 hours and analyzed for thromboxane A2 by radioimmunoassay of its stable metabolite, thromboxane B2, and for prostacyclin by radioimmunoassay of its stable metabolite, 6-k...
The Min Oscillator Uses MinD-Dependent Conformational Changes in MinE to Spatially Regulate Cytokinesis

SUMMARY In E. coli, MinD recruits MinE to the membrane, leading to a coupled oscillation required for spatial regulation of the cytokinetic Z ring. How these proteins interact, however, is not clear because the MinD-binding regionsofMinEaresequestered within a six-stranded b sheet and masked by N-terminal helices. minE mutations that restore interaction between some MinD and MinE mutants were isolated. These mutations alter the MinE structure leading to release of the MinD-binding regions and the N-terminal helices that bind the membrane. Crystallization of MinD-MinE complexes revealed a fourstranded b sheet MinE dimer with the released b strands (MinD-binding regions) converted to a helices bound to MinD dimers. These results identify the MinD-dependent conformational changes in MinE that convert it from a latent to an active form and lead to a model of how MinE persists at the MinD-membrane surface.
Fair-Rate Allocation in Multiuser OFDM-SDMA Networks

We propose algorithms for rate allocation in a multiuser orthogonal-frequency-division multiple-access (OFDMA) system, which aim to maximize the system throughput and maintain fairness among users. The system comprises of variable-rate users (with specified minimum rates) as well as constant-rate users communicating with a base station. Rate allocation criteria based on the Nash bargaining solutions are formulated. Proportional fair-rate allocation as well as fair-rate allocation in classical OFDMA systems with orthogonality constraints, are subsumed as special cases of our formulations. The resulting optimization problems, which also accommodate practical per-user power constraints, are solved using the dual decomposition techniques. The efficiencies of our proposed methods are demonstrated through simulation results.
Both daughter cells traffic and exocytose membrane at the cleavage furrow during mammalian cytokinesis

Membrane trafficking during cytokinesis is not well understood. We used advanced live cell imaging techniques to track exocytosis of single vesicles to determine whether constitutively exocytosed membrane is focally delivered to the cleavage furrow. Ultrasensitive three-dimensional confocal time-lapse imaging of the temperature-sensitive membrane cargo protein vesicular stomatitis virus protein–yellow fluorescent protein revealed that vesicles from both daughter cells traffic out of the Golgi and into the furrow, following curvilinear paths. Immunolocalization and photobleaching experiments indicate that individual vesicles accumulate at the midbody and generate a reserve vesicle pool that is distinct from endosomal and lysosomal compartments. Total internal reflection fluorescence microscopy imaging provided direct evidence that Golgi-derived vesicles from both daughter cells not only traffic to the furrow region but dock and fuse there, supporting a symmetrically polarized exocytic delivery model. In contrast, quantitative analysis of midbody abscission showed inheritance of the midbody remnant by one daughter cell, indicating that cytokinesis is composed of both symmetrical and asymmetrical stages.
Unexpected findings in the exploration of African American underrepresentation in biospecimen collection and biobanks

Racial/ethnic minorities are underrepresented in current biobanking programs. The current study utilized community-based participatory research to identify motivating factors and barriers that affect older African Americans' willingness to donate biospecimens. The standardized phone survey was administered to 78 African Americans who are 55 years old or older and live in the metropolitan Detroit area to assess their overall willingness to donate biospecimens and what factors were associated with it. The majority of the participants were willing to donate biospecimens, along with their personal information, for medical research and indicated that they did donate biospecimens when they were asked. However, African Americans were rarely asked to participate in biobanking programs. Furthermore, African Americans were not as concerned with research exploitation or as mistrusting of medical researchers as previously thought by the medical researchers. Even if African Americans were concerned over potential research exploitation or mistrust of medical researchers, these concerns or mistrust did not translate into an actual unwillingness to participate in biobanking programs. Rather, transparency in medical research and biobanking programs was more important when predicting African Americans' willingness to donate biospecimens for medical research. The findings suggest that underrepresentation of African Americans in current biobanking programs may not be due to their willingness/unwillingness to participate in such programs but rather due to a failure of medical researchers to approach them. Additionally, researchers and clinicians should focus on increasing the transparency of medical research and biobanking programs rather than changing African Americans' potential negative attitudes toward them.
Bird speciation in the tropics

The high number of species in the tropics permits two interpretations, an ecological and a genetic one. According to the genetic one, certain processes are active in the tropics (e.g. increased mutation rates or a speeding up of the number of generations) which accelerate the process of the multiplication of species. According to the ecological one, the tropical environment favours the accumulation and continued coexistence of an exceptionally high number of species, produced by the orthodox speciation process. The analysis of bird speciation favours a largely ecological interpretation. There is no evidence that speciation in the tropics differs in principle from that in the temperate zone. An alternation of dry and pluvial periods during the Pleistocene, together with continued if not accelerated mountain building in South America, south-east Asia, and New Guinea, resulted in the steady production of numerous geographical isolates some of which completed the speciation process. Ecological factors may accelerate the rate of speciation in the tropics. This includes the possibility of a greater sedentariness of populations and a correspondingly greater efficiency of geographic barriers. It includes perhaps a greater narrowness of ecological niches and consequently a better chance for a new species to carve out a niche in an already rich fauna. Among populations coexisting in a geographical isolate, only a small percentage seem to complete speciation. The others either fuse again with the parental species when the geographical isolation ends or become extinct. Size of the speciating population and its ability to find a new niche seem to be crucial for success. All guesses as to which recent species owe their origin to what particular past climatic events, must be considered as highly speculative. The unambiguous establishment of such correlations has so far been unsuccessful, at least so far as birds are concerned. Absolute figures for rates of speciation cannot be given.
A Sensitive High-Throughput Assay for Evaluating Host-Pathogen Interactions in Cryptococcus neoformans Infection

Background: Cryptococcus neoformans causes serious disease in immunocompromised individuals, leading to over 600,000 deaths per year worldwide. Part of this impact is due to the organism’s ability to thwart what should be the mammalian hosts’ first line of defense against cryptococcal infection: internalization by macrophages. Even when C. neoformans is engulfed by host phagocytes, it can survive and replicate within them rather than being destroyed; this ability is central in cryptococcal virulence. It is therefore critical to elucidate the interactions of this facultative intracellular pathogen with phagocytic cells of its mammalian host. Methodology/Principal Findings: To accurately assess initial interactions between human phagocytic cells and fungi, we have developed a method using high-throughput microscopy to efficiently distinguish adherent and engulfed cryptococci and quantitate each population. This method offers significant advantages over currently available means of assaying hostfungal cell interactions, and remains statistically robust when implemented in an automated fashion appropriate for screening. It was used to demonstrate the sensitivity of human phagocytes to subtle changes in the cryptococcal capsule, a major virulence factor of this pathogen. Conclusions/Significance: Our high-throughput method for characterizing interactions between C. neoformans and mammalian phagocytic cells offers a powerful tool for elucidating the relationship between these cell types during pathogenesis. This approach will be useful for screens of this organism and has potentially broad applications for investigating host-pathogen interactions.
Factors affecting seasonal movements of juvenile Greater Sage-Grouse: A reconceptualized nest survival model

ABSTRACT Estimating the climatic and habitat factors that affect animal movement patterns (e.g., migration, dispersal, site fidelity) is informative for management and conservation. Juvenile Greater Sage-Grouse (Centrocercus urophasianus) have been identified as having a significant influence on population growth, but relatively little is known about factors that influence survival, movement, and the potential interrelation between the two. Movement out of fall habitat has been suggested to influence the survival of juvenile Greater Sage-Grouse. We reconceptualized the nest survival model (equating movement out of a focal area with failure of a nest) to extend its use to movement data on juveniles in south-central Utah. We found that juveniles' seasonal movements were affected by a linear trend in time (β = −0.655, 95% confidence interval [CI]: −1.049 to −0.26) and by precipitation (β = −3.718, 95% CI: −6.687 to −0.749), with an interaction between the parameters (β = 0.360, 95% CI: 0.002–0.718). In the a...
State of the Art in Electromagnetic Therapeutics: Soft Tissue Applications

There is increasing use of pulsed electromagnetic fields (PEMF) as adjunctive therapy for a variety of musculoskeletal injuries. PEMF in current orthopaedic clinical practice has been employed to treat delayed and non­union fractures1–5, rotator cuff tendinitis6, spinal fusions7 and avascular necrosis8. A clinically relevant response to the PEMF signals in current clinical use is generally not immediate, requiring daily treatment for several months in the case of non-union fractures (although experimental signals now exist which elicit significantly faster response3). In contrast, clinically effective electromagnetic treatment of sprains, strains, contusions and other soft tissue injuries such as wounds, would require a physiologically meaningful response in hours or days. Until recently, application of EMF signals to other pathologies such as soft tissue and musculoskeletal injuries and post-surgical, post-traumatic and chronic wounds has been sparse. This review summarizes the present status of the use of low or non-thermal pulsed radio frequency (PRF) signals for such pathologies.
Multi-Channel High Tc SQUID System for MCG

We have developed a multi-channel high Tc SQUID system for magnetocardiography. The system consists of a 16ch SQUID in a liquid nitrogen dewar, a cylindrical permalloy magnetic shield including a movable bed, an adjustable gantry and electronics with a personal computer. The SQUIDs whose diameter is 17mm were arranged in 4 by 4 matrix with spacing of 20mm. The field resolution of the SQUID is less than 1pT/√Hz @10Hz. The liquid nitrogen dewar is compact with the diameter of 190mm. The magnetic shield is compact with the diameter of 0.85m and the length of 1.6m. It has open ends for a patient to feel relaxed. The development of a compact and low cost system is aimed for use in hospitals and bioengineering laboratories. We obtained a 16ch magnetocardiogram of the 6cm by 6cm area above the human heart and constructed time-varying magnetocardiac isofield contour maps. System noise level was about 25pT in real time mode and less than 5pT by averaging of 11 times.
Contemporary Concerns in Managing Bone Sarcoma.

One of my favorite colleagues told me about the day he invited his pediatrician father to attend his tumor board. Forty patient histories were presented by a medical oncology fellow; their imaging results were carefully reviewed by musculoskeletal radiologists, and biopsy results were reviewed by the sarcoma pathologist. At the end of the session, the colleague’s father raised his hand and said, “You presented two patients with osteosarcoma. In my 70 years as a pediatrician, I have never seen a patient with osteosarcoma.” This story reminds us how infrequent bone cancers are. It also describes a modern sarcoma tumor board, which includes representatives of numerous specialties who discuss effective management plans for patients with bone sarcomas. The favorite colleague is Robert Benjamin, senior author of Chemotherapy for Bone Sarcoma in Adults; the sarcoma tumor board is at MD Anderson Cancer Center. The outcomes of the studies reported and the prescriptions described by that sarcoma group were likely more dependent upon the care system developed at MD Anderson than on the details of a systemic remedy. The outcomes for patients treated in multiple clinics are perhaps better exemplified by the report by Zalupski et al for the Southwest Oncology Group (SWOG), which described 63 adult and teenage patients with localized extremity osteosarcoma who were treated at 24 institutions. In this single-arm cohort study, the 5-year survival rate was only 58%, and the number of patients with 90% necrosis was 48%. Grade 4 hematologic toxicity was seen in 89% of patients, and one fatality occurred as a result of chemotherapy. Numerous unspecified variables are associated with single-cohort studies. Caution must always be observedwith interpretation of such studies. The review on bone sarcoma byWagner et al highlights three such single-arm cohort studies in metastatic osteosarcoma: a study by Fox et al about the results of the chemotherapy doublet of gemcitabine and docetaxel, a study by Grignani et al of sorafenib, and a study by Grignani et al of sorafenib and everolimus. All three studies reported not meeting their definitions of success, yet Wagner et al reinterpreted the data. Interpretation of clinical success, defined as improvement in progressionfree survival in a nonrandomized clinical trial setting, is fraught with opportunity to misinterpret. The error is compounded with the authors’ statement that the Grignani et al study of sorafenib and everolimus “failed tomeet its arbitrary prespecified end point,” but that it was close enough to call a positive result. They also failed to mention that two thirds of the patients in the study had serious toxicities from this combination. In 2006, the Children’s Oncology Group reported that survivors of a bone cancer have a 40-fold increased risk of developing a grade 3, 4, or 5 serious chronic illness compared with their siblings. One in four bone cancer survivors have two or more chronic illnesses, including coronary artery disease, cardiomyopathy,
Correlates of smoking among youth: the role of parents, friends, attitudes/beliefs, and demographics

Family engagement has been shown to play a crucial role in youth cigarette use prevention and uptake. We examine cross-sectional and longitudinal data to determine whether changes in parental monitoring factors influence changes in smoking susceptibility. Two cross-sectional surveys of Florida youth (12–17 years) were conducted in 2009, with a follow-up survey in 2010. Multivariable analyses examined demographics, parent characteristics, family engagement, and parental monitoring on youth susceptibility to smoke. Cross-sectional data show eating together 6+ times/week and doing something for fun 5+ times/week were related to an increased likelihood of Very Low and decreased likelihood of High susceptibility, respectively. Parental monitoring factors and parents tell on a friend who smokes was significantly related to having Very Low susceptibility in both surveys. Mother’s education, parent smokes, family engagement factors, and parental monitoring were significant in both survey rounds. Longitudinal analyses showed change in eating together did not significantly affect the odds of change in smoking susceptibility; however, change in the frequency of doing things for fun with a parent showed decreased odds of susceptibility (OR = .63 [.49–.82]), opposite of the hypothesized direction. Lastly, as youth aged, they were more likely to experience a greater odds of decreased susceptibility (OR14-15y = 1.47 [1.08–1.99] and OR≥16y = 1.40 [1.05–1.84], respectively) and less likely to experience an increased odds of susceptibility (OR14-15y = .65 [.49–.86] and OR≥16y = .72 [.56–.93], respectively). We found mixed results for family engagement and parental monitoring on changes in youth smoking susceptibility. Cross-sectional data showed general associations in the expected direction; however, longitudinal analyses showed family engagement variables had significance, but in the opposite hypothesized direction.
Border crossings: Perceptual and post-perceptual object representation

Carey's claim that no object representations are perceptual rests on a faulty view of perception. To delineate origins of post-perceptual (“conceptual” or “core cognitive”) representation, we need a more accurate view of perceptual representation.
Topological Mapping to Estimate Numbers of Bark-inhabiting Insects

The methodology of a topological mapping procedure for estimating the total number of insects inhabiting a tree trunk is presented. Data necessary for using the procedure are insect densities at measured intervals on the bole. The procedure minimizes errors resulting from smoothing, regression or extrapolation and provides estimates suitable for evaluating bias and variability of other sampling plans.
Effects of relaxin on rat atrial myocytes. II. Increased calcium influx derived from action potential prolongation

Relaxin produces positive inotropic and chronotropic effects in rat hearts. The effect of relaxin on the action potential duration (APD) of single quiescent rat atrial cells was investigated with a whole cell patch clamp. Relaxin induced a significant, dose-dependent prolongation of the APD. This effect was maximal at 200 ng/ml (nominal concentration of 33.6 nM), which caused, on average, a 57% increase in the time taken to reach 90% repolarization. The effect of relaxin was blocked by the protein kinase A inhibitor 5-24 amide, indicating that its effect is mediated by an adenosine 3',5'-cyclic monophosphate-dependent mechanism. The increased APD induced by relaxin caused an enhanced entrance of calcium, with the charge carried through voltage-activated calcium channels increased by approximately 25%. This increase was not due to a direct modulation of calcium currents (20); rather, it was a consequence of the longer period of cellular depolarization. Our findings that relaxin increased the APD and therefore increased the calcium influx in atrial myocytes could explain the positive inotropic effects induced by relaxin in atrial preparations.
Comparison of gas chromatography-electron capture and enzyme-linked immunosorbent assay for deoxynivalenol in milled fractions of naturally contaminated wheat.

An enzyme-linked immunosorbent assay (ELISA) for deoxynivalenol was compared with a gas chromatography-electron capture assay to determine deoxynivalenol levels in milled fractions of wheat. The milling provided eight fractions: first, second, and third break flours; first, second, and third reduction flours; brans; and shorts. The difference between levels of deoxynivalenol quantitated by ELISA or gas chromatography did not depend significantly on the wheat samples or milled wheat fractions. For none of the fractions or samples did the differences differ significantly (P = 0.05) from zero. Based on these comparative tests, ELISAs for deoxynivalenol in milled wheat fractions should provide reliable results rapidly and economically in a commercial setting.
Psoriatic plaques "koebnerizing" to areas of acanthosis nigricans in an obese female: clues to a common pathway?

Recent evidence suggests that the activation of several growth factor receptors (EGFR, IGFR1, and FGFRs) is a possible cause of acanthosis nigricans, a skin disorder characterized by velvety thin plaques in skin folds and often seen in patients with insulin resistance. The authors report a 14-year-old obese (body mass index = 38.5kg/m2) girl with a history of polycystic ovarian syndrome and pre-diabetes who presented with psoriatic plaques in her scalp and, subsequently, in areas mostly confined to where she had characteristic lesions of acanthosis nigricans. The authors propose that this as-of-yet unreported observation may represent a preferential koebnerization phenomenon where the abnormal keratinocyte proliferation in acanthosis nigricans may serve as the epidermal “micro-trauma” necessary to incite the prototypical isomorphic response seen in psoriasis.
Cu 2+-labeled dansyl compounds as fluorescent and PET probes for imaging apoptosis

Compound DNSTT-Cu2+, a novel chelate of Cu2+ with DOTA conjugated to a fluorescent dansyl fragment, is developed for imaging cell apoptosis. Apoptotic U-87MG cells could be selectively visualized by the fluorescence of DNSTT-Cu2+ from cytoplasm of cells, confirmed by the fluorescence of apoptosis cells co-labeled with Alexa Fluor 568-labeled annexin V, a conventional probe for selectively labeling membranes of apoptosis cells. A radioactive 64Cu2+ analog, DNSTT-64Cu2+, was easily synthesized, providing a potential PET probe for imaging apoptosis in vivo.
An Economic Approach to Price Fixing

This article examines optimal policy toward coordinated oligopolistic price elevation. First, it analyzes the social welfare implications of enforcement, elaborating the value of deterrence and the nature of possible chilling effects. Then, it explores a variety of means of detection, with particular attention to the sorts of errors that may arise under each. Finally, it examines the level and type of sanctions that should be employed. It emerges that there is remarkably little overlap in content between the present investigation and prior legal policy work on the subject. Some central issues have been ignored while particular resolutions of others have been taken for granted, thereby indicating the need for wholesale reassessment.
Ableist Shame and Disruptive Bodies: Survivorship at the Intersection of Queer, Trans, and Disabled Existence

Disabled people’s sexuality is fraught with tensions of desexualization and criminalization – at once presumed nonexistent while pathologized as terrifying and perverse. As sexuality is intricately tied to notions of gender identity (themselves dependent on the able-normative body), disabled people exist more often as objects in othering narratives than as subjects, let alone narrators, of their own. While people with all types of disabilities face astounding rates of sexual violence, those who are also queer, trans, or otherwise LGBTQIAP-identified inhabit bodies marginalized as deviant in multiple ways. Shared experiences of pathologization severely impact access to support, resources, mental health care, and healing spaces for queer and trans disabled survivors, whose experiences with gendered and sexual violence often transgress boundaries between home, school, institutions (and other carceral spaces), and the streets. This chapter will include discussion of exacerbating factors in trauma and erasure of queer and trans disabled survivors, such as the presumptions of incompetence and caregiver benevolence, the delegitimization of disabled people’s genders and sexualities, and the internal violence of ableist shame.