cssi/SciSciGPT-SciSciNet huggingface dataset:
Markers of cholesterol transport are associated with amyloid deposition in the brain

Cholesterol is implicated in the development of late-onset Alzheimer's disease (AD). We sought to determine the associations between beta amyloid (Aβ) plaque deposition in vivo using Pittsburgh compound B (PiB) and several indices of cholesterol homeostasis (i.e., total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, apolipoprotein E (ApoE), clusterin, oxysterol metabolites of cholesterol, and previously reported genes associated with late-onset AD) in 175 nondemented elderly subjects. High Aβ deposition was associated significantly with a lower Mini-Mental State Examination score (<27 points, p = 0.04), high systolic blood pressure (p = 0.04), carrying the apolipoprotein E epsilon 4 allele (p < 0.01), and lower plasma ApoE levels (p = 0.02), and variation in the ABCA7 (p = 0.02) and EPHA1 genes (p = 0.02). Cholesterol measures were not related to Aβ deposition in this cohort of nondemented elderly adults. However, plasma and genetic factors relating to cholesterol transport were associated with Aβ deposition in the brain. A better understanding of cholesterol transport mechanisms may lead to the design of potential targets for the prevention of Aβ deposition in the brain.
Lunar Gravitational Capture Conditions

Certain classes of lunar trajectories allow spacecraft to approach the moon from outside its sphere of ine uence and to end up in a temporarily captured state around the moon without any thrusting necessary. The spacecraft’ s state at the moon associated with these efe cient types of capture is investigated. First, analysis is done on objects approaching the moon from a direction that results in the lowest eccentricity at perilune. Following that, analysis is done on objects approaching the moon with trajectories that originate from the Earth. This second set of orbits are ballistic capture transfer trajectories that allow spacecraft to go from low Earth orbit to lunar capture with only one engine burn at Earth. The properties investigated provide insight to this particular form of transfer and can help in mission design.
Folding and misfolding mechanisms of the p53 DNA binding domain at physiological temperature.

p53 modulates a large number of cellular response pathways and is critical for the prevention of cancer. Wild-type p53, as well as tumorigenic mutants, exhibits the singular property of spontaneously losing DNA binding activity at 37°C. To understand the molecular basis for this effect, we examine the folding mechanism of the p53 DNA binding domain (DBD) at elevated temperatures. Folding kinetics do not change appreciably from 5°C to 35°C. DBD therefore folds by the same two-channel mechanism at physiological temperature as it does at 10°C. Unfolding rates, however, accelerate by 10,000-fold. Elevated temperatures thus dramatically increase the frequency of cycling between folded and unfolded states. The results suggest that function is lost because a fraction of molecules become trapped in misfolded conformations with each folding-unfolding cycle. In addition, at 37°C, the equilibrium stabilities of the off-pathway species are predicted to rival that of the native state, particularly in the case of destabilized mutants. We propose that it is the presence of these misfolded species, which can aggregate in vitro and may be degraded in the cell, that leads to p53 inactivation.
Pulse width modulation for reduced peak power full-swing on-chip interconnect

A full-swing on-chip interconnect using pulse width modulation (PWM) was designed and fabricated in 0.25μm CMOS for application in a tiled signal processing array architecture targeting wireless sensor nodes. Measurements show a decrease in the worst case power of 7% over traditional binary signaling for 11.8mm long wires at 10Mbps throughput and 0.7V VDD. Power savings are projected to increase to 20% for 30mm long wires, while becoming beneficial for shorter wires at future process nodes without multiple wires or power rails. Power savings occur for wire lengths greater than 1.34mm and reach 20% at 3.03mm at the 32nm node. Savings are also projected to reach 18.2% when used on wires spanning 16 tiles in the target architecture.
Effect of sodium fluoride solutions of varying pH on solubility of bovine enamel.

Abstract Neutron-irradiated dental enamel was treated with NaF solutions of varying pH and ionized fluoride concentrations. The pH of one group of fluoride solutions was adjusted by the addition of HCl acid and another group by the addition of HF acid. Comparison of phosphorus (P32) dissolution in acid buffer before and after treatment with the fluoride solutions showed that a reduction in enamel solubility of 94% could be obtained. The solubility reduction was dependent on both pH and ionized fluoride concentrations. Phosphorus (P32) loss from enamel during NaF treatment was also measured and it was found to increase with a decrease in pH but was influenced by the ionized F concentration and/or enamel solubility.
GMM with more moment conditions than observations

Abstract When there are more moment conditions than observations, the usual GMM weighting matrix is singular. We show that using the generalized inverse is not a good idea. With continuous updating, the criterion function equals one for every parameter value.
Gamma rays and energetic particles from primordial black holes

The standard model of quarks and leptons is used to discuss the signatures of black-hole evaporations. A firm bound on the primordial black hole abundance is obtained from MeV data. It is argued that the MeV bound can be improved by exploiting the new generation of TeV and PeV telescopes.
Efficacy, side effects and tolerance compared during headache treatment with three different calcium blockers.

SYNOPSIS Experiences gained in this laboratory during long-term, separate prophylactic trials utilizing three different calcium channel blockers among patients with common migraine, classic migraine, mixed and chronic cluster headaches are reviewed. Nifedipine provided symptomatic improvement among 65% of patients with common migraine and among 77% of patients with classic migraine. Forty-one percent of patients with mixed headache reported some relief of head pain. Sixty percent of patients with chronic cluster reported improved control of their headaches. Verapamil produced improved control of symptoms in 81% of patients with common migraine, 72% of those with classic, 67% of those with mixed and 79% of those with cluster. Nimodipine was reported to be beneficial among 84% of patients with common migraine, among 73% of those with classic migraine and among 53% with chronic cluster. Only 33% of patients treated with nimodipine for mixed headache reported improvement. Side effects were more common with nifedipine (71%) than with verapamil (41%) and were least common with nimodipine (20%). Tolerance developed in 42% of those treated with nifedipine and in 49% of those treated with verapamil. Development of tolerance with nimodipine was rare (4%). Each of these three calcium channel blockers showed different and specific therapeutic efficacies which differed according to the clinical classification of the different types of vascular head pain undergoing treatment.
An analysis of preferred orientation in YBa2Cu3O7–x superconducting films deposited by CVD on single-crystal and polycrystalline substrates

YBa2Cu3O7–x films were deposited by chemical vapor deposition (CVD) onto single-crystal MgO, single-crystal Al2O3, and polycrystalline Al2O3 substrates, characterized before and after annealing, and tested for their superconducting properties. The preferred orientation in the films was analyzed (i) with pole figures and (ii) by comparison of experimental x-ray powder diffraction patterns with those calculated for the material using the March–Dollase function to model the degree of preferred orientation. Preferred orientation was significant in as-deposited films, with March coefficients ranging from 0.1–0.5 (random orientation would have a coefficient of 1.0). The (006) pole figures of the films on single crystal substrates exhibited uniquely symmetric patterns. On single-crystal MgO before annealing, a minor secondary orientation of (006) poles in the film was observed in a pattern consistent with the symmetry of major crystallographic directions of MgO. On single-crystal Al2O3 after annealing, a “dual orientation” phenomenon was observed. The high-temperature anneal destroyed the orientation and superconducting properties of the CVD films deposited at high temperatures.
Central behavioral interactions between ethanol, (-)-nicotine, and (-)-cotinine in mice

A high correlation between alcohol use and smoking has long been suggested by epidemiological data. We examined the potential behavioral interactions between ethanol and nicotine using ethanol-induced motor incoordination as the test response in mice. Effect of pretreatment of various doses of (-)-nicotine, (-)-cotinine, a major metabolite of nicotine, and (+)-nicotine administered ICV on ethanol (IP)-induced motor incoordination was investigated. (-)-Nicotine (0.19, 0.38, 0.77 and, 1.54 nmoles ICV) produced significant attenuation of motor incoordination due to ethanol (2 g/kg IP) in a nearly dose-related manner which was blocked by ICV hexamethonium and trimethaphan, both purported nicotinic antagonists. (-)-Cotinine (0.35, 0.70, 1.41 nmole ICV) produced similar attenuation but was les potent than (-)-nicotine. Attenuation by (+)-nicotine (0.19, 0.38, and 0.77 nmoles ICV) was also significant but only at 0.77 nmole dose level. (+)-Nicotine-induced attenuation of motor incoordination by ethanol was antagonized by nicotinic antagonists. Data obtained suggest a central behavioral interaction between ethanol and nicotine at least through the participation of cholinergic nicotinic receptors.
Coherent-incoherent transition and relaxation in condensed-phase tunneling systems.

The tunneling dynamics of the spin-boson problem has been computed using discretized path-integral simulations for temperatures T and couplings, i.e., the Kondo parameter \ensuremath{\alpha}, spanning the entire T-\ensuremath{\alpha} plane. The inherent problem of alternating weights has been solved using a combination of the stationary-phase Monte Carlo method and contour-distortion techniques. A transition from coherent to purely incoherent relaxation was observed for the spin correlation function. The time correlation functions and the location of the coherent-incoherent boundary on the T-\ensuremath{\alpha} plane are well described by the noninteracting-blip approximation. In the deep-tunneling limit of large \ensuremath{\alpha}, low T, and high bath frequency, the system relaxes exponentially, with its relaxation time constant following a power-law temperature dependence, in accord with perturbation theory. At higher T and low bath frequency, the relaxation time crosses over to a classical Arrhenius temperature dependence, reflecting the onset of activated processes. For a narrow region within 1/21, numerical results suggest that the system undergoes incoherent relaxation, with a short-time exponential decay, followed by a long-time tail of the power-law type. The short-time exponential relaxation time follows a peculiar power-law temperature dependence, with the relaxation rate increasing as a function of decreasing temperature.
Street fighting: Placing the crisis of masculinity in David Fincher's Fight Club

Recent writing in geography and its cognate disciplines suggests that the crisis of masculinity is in large part about the marginalization of men. With this paper, we take this spatial metaphor to task using David Fincher's Fight Club as a foil against which we try to pin larger issues of masculinity and urban life. That Flight Club can be viewed as alienated men confronting their homosocial and homoerotic selves through laddish revolutionary pranks detracts from its potential as a commentary on larger social tensions and contradictions. Men are simultaneously in the center and at the margins of what Bourdieu describes as the habitus; they are simultaneously playful and despairing, they are simultaneously alienated and the purveyors of hegemonic order. Fincher's movie engages these spatial metaphors and offers an opportunity to destroy the habitus, to change both masculinity and culture.
The accelerator store: A shared memory framework for accelerator-based systems

This paper presents the many-accelerator architecture, a design approach combining the scalability of homogeneous multi-core architectures and system-on-chip's high performance and power-efficient hardware accelerators. In preparation for systems containing tens or hundreds of accelerators, we characterize a diverse pool of accelerators and find each contains significant amounts of SRAM memory (up to 90p of their area). We take advantage of this discovery and introduce the accelerator store, a scalable architectural component to minimize accelerator area by sharing its memories between accelerators. We evaluate the accelerator store for two applications and find significant system area reductions (30p) in exchange for small overheads (2p performance, 0p--8p energy). The paper also identifies new research directions enabled by the accelerator store and the many-accelerator architecture.
The effect of Lewis number on the stability of a catalytic reaction

An extensive numerical study was carried out to determine the effect of Lewis number on the stability of a chemical reaction occurring inside a porous catalyst pellet. It is found that when the Lewis number is different from 1, the coupling between the concentration and temperature causes several pathological effects during the transient periods. One of the most interesting phenomenon is the occurrence of a unique unstable steady state with a periodic appearance of a very hot spot.
Low Density Lipoprotein Receptor Activity in Fibroblasts Cultured from Diabetic Donors

Low density lipoprotein (LDL) receptor activity was evaluated in cultured skin fibroblasts from diabetics and nondiabetic controls to evaluate whether intrinsic abnormalities of the LDL pathway exist, which might account for the premature atherosclerosis associated with diabetes mellitus. LDL receptors did not differ between cells grown from 16 diabetics (7 insulin-dependent, 9 non-insulin-dependent) or from 16 nondiabetic controls. An inverse relationship between LDL receptor activity and cell density was observed (y = 1.35 × −1.22, r = 0.90, P < 0.001), which appeared the same for diabetic and nondiabetic cells. Normalized values for LDL degradation by diabetic and nondiabetic cell strains were 1.52 ± 0.42% of added LDL/106 cells and 1.34 ± 0.28, respectively ( P = NS). The kinetics of the LDL receptor also appeared to be the same in cells derived from a diabetic and a nondiabetic donor. LDL receptor activity in diabetic cells increased appropriately in response to physiologic concentrations of insulin in the incubation medium. Thus, LDL receptor activity appears to be normal in diabetic cell strains. Therefore, these results do not support the possibility that alterations in the LDL pathway contribute to the accelerated atherosclerosis associated with diabetes.
The two consecutive M substates in the photocycle of bacteriorhodopsin are affected specifically by the D85N and D96N residue replacements

The photocycle of the proton pump bacteriorhodopsin contains two consecutive intermediates in which the retinal Schiff base is unprotonated; the reaction between these states, termed M1 and M2, was suggested to be the switch in the proton transport which reorients the Schiff base from D85 on the extracellular side to D96 on the cytoplasmic side (Varo and Lanyi, Biochemistry 30, 5016-5022, 1991). At pH 10 the absorption maxima of both M1 and M2 could be determined in the recombinant D96N protein. We find that M1 absorbs at 411 nm as do M1 and M2 in wild-type bacteriorhodopsin, but M2 absorbs at 404 nm. Thus, in M2 but not M1 the unprotonated Schiff base is affected by the D96N residue replacement. The connectivity of the Schiff base to D96 in the detected M2 state, but not in M1, is thereby established. On the other hand, the photostationary state which develops during illumination of D85N bacteriorhodopsin contains an M state corresponding to M1 with an absorption maximum shifted to 400 nm, suggesting that this species in turn is affected by D85. These results are consistent with the suggestion that M1 and M2 are pre-switch and post-switch states, respectively.
The automatic implantable cardioverter defibrillator: T wave sensing in the newest generation.

The AICD uses an automatic gain control amplifier for detecting the small electrograms during ventricular fibrillation. The latest generation of the AICD appears to have a more sensitive lock on gain amplifier, as 6 of 76 patients implanted with the new AICD had double counting of the QHS-T wave complex resulting in asymptomatic discharges. Solutions to the problem of limiting these asymptomatic discharges are difficult and include slowing of the heart rate with beta blockers, changing the lead system, or replacement of the device. One of the six patients was treated with beta blockers. Three patients had their device changed, two patients requested the inactivation of their device until a rate programmable unit was available. The potential for T wave sensing in a lock on gain amplifier represents the unique dilemma between detecting small electrograms of ventricular fibrillation, and detecting diastolic events which occur shortly after the QRS complex.
Impedance Spectroscopy Characterization of a Piezoresistive Structural Polymer Composite Bulk Sensor

In this study, self-monitoring characteristics of a new piezoresistive structural polyester polymer composite bulk sensor were investigated under various loading conditions using impedance spectroscopy (IS). IS was used to estimate the bulk resistance of the piezoresistive polymer composite and the contact resistance of the two-probe measuring system used, along with the stress and shape dependence of these resistances. The piezoresistive behavior of cylindrical specimens in compression and circular disk specimens in bending and splitting tension showed repeatable characteristics. The contact resistances were about 1 % and 4.4 % of the bulk resistances for the cylindrical and circular disk specimens, respectively. The contact resistances were relatively small compared to the bulk resistances, and the change in contact resistance with applied stress was quantified. The average piezoresistivity coefficient for cylindrical specimens was 0.015 MPa−1 in compression, and for the circular disk specimens the coefficients were 3.1 × 10−4 MPa−1 and 4.62 × 10−4 MPa−1 under bending and splitting tensile loading, respectively. An incremental stress-resistivity model was used to predict the observed behavior of the piezoresistive polymer composite.
Targeting AKT with the allosteric AKT inhibitor MK-2206 in non-small cell lung cancer cells with acquired resistance to cetuximab

The epidermal growth factor receptor (EGFR) is a central regulator of tumor progression in human cancers. Cetuximab is an anti-EGFR monoclonal antibody that has been approved for use in oncology. Despite clinical success the majority of patients do not respond to cetuximab and those who initially respond frequently acquire resistance. To understand how tumor cells acquire resistance to cetuximab we developed a model of resistance using the non-small cell lung cancer line NCI-H226. We found that cetuximab-resistant (Ctx (R) ) clones manifested strong activation of EGFR, PI3K/AKT and MAPK. To investigate the role of AKT signaling in cetuximab resistance we analyzed the activation of the AKT pathway effector molecules using a human AKT phospho-antibody array. Strong activation was observed in Ctx (R) clones for several key AKT substrates including c-jun, GSK3β, eIF4E, rpS6, IKKα, IRS-1 and Raf1. Inhibition of AKT signaling by siAKT1/2 or by the allosteric AKT inhibitor MK-2206 resulted in robust inhibition of cell proliferation in all Ctx (R) clones. Moreover, the combinational treatment of cetuximab and MK-2206 resulted in further decreases in proliferation than either drug alone. This combinatorial treatment resulted in decreased activity of both AKT and MAPK thus highlighting the importance of simultaneous pathway inhibition to maximally affect the growth of Ctx (R) cells. Collectively, our findings demonstrate that AKT activation is an important pathway in acquired resistance to cetuximab and suggests that combinatorial therapy directed at both the AKT and EGFR/MAPK pathways may be beneficial in this setting.
Effects of interstitial content on the texture of swaged and of recrystallized titanium wire

Abstract The textures of swaged and of recrystallized wires of titanium of three purity levels (zone refined, commercial A-50, and commercial A-70) were investigated. The texture of the cold-worked state of all three materials is a strong 〈1010〉 fiber texture. For grain sizes less than about 3 μm the recrystallized texture is the same as that in the as-swaged condition. For larger grain sizes, the 〈1010〉 direction rotates ± 15 degrees from the wire axis in all three materials. In the case of the zone-refined material a similar rotation occurs for the basal plane with respect to the wire axis; however, this does not occur for the less-pure A-50 and A-70 materials. Some possible reasons for this effect of purity are discussed.
Cuentas y cultura material: la reconstrucción del Real Palacio de Lima después del terremoto de 1746

This article is an analysis and transcription of an account book on the rebuilding of the Royal Palace of Lima, after the devastating earthquake of 1746. The document contains detailed information about the origin and costs of the work force and the products used in the rebuilding, information rarely found in documentation from the period. It thus offers a rich entryway into a number of important themes regarding eighteenth-century Peru. These include material culture, the life and death of slaves, and construction techniques. It contributes to the understanding of social and economic history of colonial Peru and more specifically to late colonial architecture and accounting, as well as the history of the Palace itself.
Antagonism of Sexual Behavior in Female Rats by Ventromedial Hypothalamic Implants of Antiestrogen

The present experiments sought to identify brain regions in which implants of an antiestrogen would antagonize the ability of a systemic estradiol treatment to activate sexual behavior in female rats. In experiment 1, ovariectomized female rats were implanted subcutaneously with 5-mm Silastic capsules containing a 5% concentration of estradiol and injected with 500 micrograms progesterone 2 days later, 4-5 h before testing for sexual behavior. Bilateral intracranial implants of 1% crystalline concentrations of the high-affinity antiestrogens monohydroxytamoxifen (TAM) or keoxifene placed into the ventromedial nucleus of the hypothalamus (VM) 24 h prior to estradiol treatment significantly reduced lordosis responsivity compared with control females receiving empty cannulae. Implants of 1% TAM into the medial preoptic area or medial amygdala 24 h prior to estradiol that no significant effect on lordosis. Similarly, implants of 1% TAM into the VM 12 h after estradiol had no effect on lordosis. In experiment 2, lordosis was activated by subcutaneous implants of Silastic capsules containing 1% estradiol plus 500 micrograms progesterone. In this experiment, implants of 1% TAM into the VM 24 h prior to estradiol significantly reduced lordosis only if both cannulae tips were in, or adjacent to, the VM. Females receiving intracranial 1% TAM, but whose cannulae (even unilaterally) were outside the VM, had levels of lordosis equivalent to those of control females. Increasing the concentration of intracranial TAM to 10% virtually eliminated lordosis in females with bilateral implants in the VM, whereas females receiving intracranial 10% TAM in the region of, but outside, the VM showed no evidence of a lordosis deficit.(ABSTRACT TRUNCATED AT 250 WORDS)
Host specificity of entomophilic nematodes—A review

Abstract Entomophilic nematodes can be biologically manipulated either as biological control agents or as biological insecticide agents. The characteristics, mode of application, and degree of specificity for each of these is considered. The importance of host specificity information for nematode parasites potentially useful in controlling insect pests is emphasized. A general discussion of host specificity and the factors influencing host specificity of entomophilic nematodes is presented. Characteristics of nematodes of the genus Heterotylenchus are discussed while particular emphasis is placed on H. autumnalis, a potentially useful biological control agent of the face fly, Musca autumnalis. Greater detail of the bionomics of this nematode, its attributes and disadvantages as a successful control agent are considered. The factors resulting in host specificity of this parasite, especially host resistance, in Musca domestica, Orthellia caesarion, and Ravinia l'herminieri, are encapsulation and melanization. It is emphasized that biological control workers are working with a dynamic, evolving host-parasite system and that really they are faced with the same problems (resistance of the host and target specificity of the applied material) originally and still confronting the toxicologist and economic entomologist.
Reliable protein structure refinement using a physical energy function

In the past decade, significant progress has been made in protein structure prediction. However, refining models to a level of resolution that is comparable with experimental results and can be used in studies like enzymatic activity still remains a major challenge. We have previously demonstrated that our modular protein-solvent energy function, uniquely involving a potential of mean force description for hydrophobic solvation, works well in protein globular structure prediction and loop modeling. In this work, we couple protein-solvent energy function with our global optimization method stochastic perturbation with soft constraints and use them to refine a collection of template models from submitted predictions to recent Critical Assessment of Techniques for Protein Structure Prediction blind prediction contests. A prediction protocol based on a selection of structures with the lowest energy is able to successfully refine all of the test proteins, and, more importantly, our energy function does not show degradation in prediction when sampling is exhausted.
An Adaptive Sampling Algorithm with Applications to Denial-of-Service Attack Detection

There is an emerging need for the traffic processing capability of network security mechanisms, such as intrusion detection systems (IDS), to match the high throughput of today's high-bandwidth networks. Recent research has shown that the vast majority of security solutions deployed today are inadequate for processing traffic at a sufficiently high rate to keep pace with the network's bandwidth. To alleviate this problem, packet sampling schemes at the front end of network monitoring systems (such as an IDS) have been proposed. However, existing sampling algorithms are poorly suited for this task especially because they are unable to adapt to the trends in network traffic. Satisfying such a criterion requires a sampling algorithm to be capable of controlling its sampling rate to provide sufficient accuracy at minimal overhead. To meet this utopian goal, adaptive sampling algorithms have been proposed. In this paper, we put forth an adaptive sampling algorithm based on weighted least squares prediction. The proposed sampling algorithm is tailored to enhance the capability of network based IDS at detecting denial-of-service (DoS) attacks. Not only does the algorithm adaptively reduce the volume of data that would be analyzed by an IDS, but it also maintains the intrinsic self-similar characteristic of network traffic. The latter characteristic of the algorithm can be used by an IDS to detect DoS attacks by using the fact that a change in the self-similarity of network traffic is a known indicator of a DoS attack.
A mixed-integer linear programming problem which is efficiently solvable

Abstract Efficient algorithms are known for the simple linear programming problem where each inequality is of the form x j − x i ≤ a ij . Furthermore, these techniques extend to the integer linear programming variant of the problem. This paper gives an efficient solution to the mixed-integer linear programming variant where some, but not necessarily all, of the unknowns are required to be integers. The algorithm we develop is based on a graph representation of the constraint system and runs in O (| V || E | + | V | 2 lg| V |) time. It has several applications including optimal retiming of synchronous circuitry, VLSI layout compaction in the presence of power and ground buses, and PERT scheduling with periodic constraints.
Maps to weight space in Hida families

Let \(\bar \rho\) be a two-dimensional Fp-valued representation of the absolute Galois group of the rationals. Suppose \(\bar \rho\) is odd, absolutely irreducible and ordinary at p. Then we show that \(\bar \rho\) arises from the irreducible component of a Hida family (of necessarily greater level than that of \(\bar \rho\)) whose map to weight space, including conjugate forms, has degree at least 4.
The influence of diblock copolymers on the structure and properties of polybutadiene-polyisoprene blends

The structure and properties of a ternary polymer system comprised of 1, 4 polybutadiene, cis 1, 4 polyisoprene, and the corresponding 1, 4 polybutadiene/cis 1, 4 polyisoprene diblock copolymer have been investigated. Dynamic mechanical properties were measured as a function of frequency (3.5 to 110 Hz) and temperature (−135 to 40°C). Thermomechanical analysis and transmission electron microscopy provided additional information on the, phase relationships in the various specimens. The blends studied covered the entire triangular composition diagram; both slow solvent evaporation and rapid spin casting techniques were employed in the sample preparation. Results indicate that the BI diblock is a single phase material whereas binary blends of the two homopolymers are two-phase in nature. Ternary blends of the two homopolymers with diblock and binary blends of a single homopolymer with diblock can be one or two phase materials depending on the sample composition and the ratio of B to I units in the diblock. All evidence From the dynamic, thermomechanical and microscopic experiments is used to elucidate the influence of the diblock in these polymer blends.
Imaging of giant cell tumor of bone

Giant cell tumor (GCT) of bone is a benign but locally aggressive and destructive lesion generally occurring in skeletally mature individuals. Typically involving the epiphysiometaphyseal region of long bones, the most common sites include the distal femur, proximal tibia and distal radius. On radiographs, GCT demonstrates a lytic lesion centered in the epiphysis but involving the metaphysis and extending at least in part to the adjacent articular cortex. Most are eccentric, but become symmetric and centrally located with growth. Most cases show circumscribed borders or so-called geographical destruction with no periosteal reaction unless a pathological fracture is present. There is no mineralized tumor matrix. Giant cell tumor can produce wide-ranging appearances depending on site, complications such as hemorrhage or pathological fracture and after surgical intervention. This review demonstrates a spectrum of these features and describes the imaging characteristics of GCT in conventional radiographs, computerized tomography scans, magnetic resonance imaging, bone scans, positron emission tomography scans and angiography.
Anesthesia for Cesarean section in a patient with paraplegia resulting from tumour metastases to spinal cord.

Purpose: Spinal cord injured patients present multiple unique challenges to the anesthesiologist. These include choice of muscle relaxant and management of autonomic hyperreflexia. We report the anesthetic management for Cesarean delivery in a patient who was paraplegic due to spinal canal metastases. Preeclampsia and fever complicated this case.
Willingness-to-pay stated preferences for 8 health-related quality-of-life domains in psoriasis: a pilot study.

Background Psoriasis is a chronic skin condition that has a major impact on health-related quality of life (QOL). We evaluated health-related QOL via willingness to pay and a ranking task for 8 domains of health relevant to psoriasis: intimacy, physical comfort, self-care, ability to work or volunteer, ability to concentrate, emotional health, social comfort, and ability to sleep. Objective The goals of the study were to pilot test a new method to measure QOL impact in psoriasis and identify the areas of life most affected by psoriasis. Methods Forty participants with a history of psoriasis were interviewed in a face-to-face format. First, participants were asked to rank the 8 domains of health we were investigating. Second, patients were asked how much money they would be willing to pay for a hypothetical cure for each domain of health. Responses in US dollars were interpreted as strength of preference rather than absolute monetary values. Results About half of the patients in the sample (48%) were female, 60% had a college degree or further education, and 38% had an income level over $45,000/y. Physical comfort, social comfort, and emotional health were highly ranked by more than 75% of respondents. Ability to concentrate was least likely to be affected by psoriasis with just a quarter (25.7%) of respondents ranking this domain as important. The median amount patients were willing to pay for a hypothetical cure of psoriasis specific to a particular domain was highest for physical comfort ($2000, 25th quartile=$500, 75th quartile=$5500) and emotional health ($2000, 25th quartile=$250, 75th quartile=$5000), and lowest for ability to sleep ($625, 25th quartile=$50, 75th quartile=$5000). Limitations The sample size is modest for this pilot study. Willingness to pay as a method of eliciting stated preferences for qualitative aspects of health may be influenced by individual perception of money. Conclusions This study successfully pilot tested a willingness-to-pay method and a ranking task to measure the relative severity of 8 domains of health-related QOL and found that physical comfort, social comfort, and emotional health were the domains of health most affected by psoriasis.
Scaling of Fluorescence Stokes Shift and Superradiance Coherence Size in Disordered Molecular Aggregates

Fluorescence line shapes and cooperative spontaneous emission in disordered one-dimensional molecular aggregates are calculated using closed expressions derived by applying the method of optimal fluctuation. A simple scaling relation Ls ∼ ωs-1/2 is established between the low temperature disorder-induced Stokes shift ωs and the superradiance enhancement factor Ls. Scaling of the Stokes shift with aggregate size, and the time-dependent Stokes shift are discussed as well. Excellent agreement is obtained with numerical simulations.
Overcoming obstacles to behavior change in diabetes self-management.

PURPOSEthis study describes how 5 individuals with type 2 diabetes overcame obstacles that interfered with maintaining behavior changes in diet, exercise, and self-monitoring of blood glucose (SMBG...
A new model for diffusion weighted MRI: Complete Fourier direct MRI

The diffusion weighted MR signal is modeled using particle methods. The model shows that the signal is the Fourier transform of the distribution function of the number of spins at the initial time at a given position with a given displacement integral value. The distribution function is computed via Fourier transform steps that keep the Hermitian property of the signal in order to guarantee that the distribution function is real valued. The function, which depicts the tissue microstructure ‘as it is’ without being tied to any expansions, transformations and assumptions such as Markovian property or symmetry about the spin motions, is displayed using isosurfaces overlayed on the spin density map for a fixed baboon brain sample.
Magnetic resonance imaging in congenital heart disease: what to do with what we see and don't see?

Magnetic resonance imaging (MRI) is increasingly being applied to critically ill newborns with congenital heart disease (CHD) with the hope of understanding mechanisms accounting for adverse neurodevelopmental outcome. This powerful technique has opened an unprecedented window into normal development and pathogenesis during fetal life and surrounding surgery. Much as the technological advances of cardiopulmonary bypass, cardiac intensive care, and transcatheter and surgical techniques have translated into improved survival for neonates with complex congenital heart lesions, MRI promises to elucidate mechanisms and measure outcomes in a way that will inform treatment and establish neurointensive care to lessen neurologic morbidity. Many agree that improving neurodevelopmental outcome in CHD is the preeminent challenge to the field.1 MRI studies in CHD have made the important and surprising observations that (1) brain injury is present before surgery,2 (2) injury is most commonly focal affecting the white matter,3 and (3) brain development is delayed in term infants with CHD.4 Despite its promise as a sensitive early outcome variable that could be used to structure interventional studies with novel trial design,5 success to date has largely been descriptive, identifying clinical risk factors in limited case series. A particular challenge applying these findings to clinical practice is that the incidence of injury and associated risk factors are often unique to each form of CHD.6 For this reason, the approach has not substantially altered clinical care to date. However, several themes have emerged from multiple studies, providing confidence that the identified risk factors are valid and potent. These include the significance of postoperative hypotension,3,6 hypoxemia3 and diminished regional cerebral oxygen saturation.6,7 Although multiple studies have noted the high frequency of preoperative brain injury, particularly in neonates with transposition of the great arteries (TGA),2,6,8 few risk factors have been identified …
Online test and fault-tolerance for nanoelectronic programmable logic arrays

Fault-tolerance is one of the major challenges facing nanoelectronic systems. Previous defect-tolerance techniques have focused on offline testing and are ill-suited for handling device death. We propose a fault-tolerance scheme for nanoelectronic PLAs that is based on checkpointing. With low overhead, our scheme is able to test and diagnose crosspoint faults that may appear in the PLA during its operational lifetime.We also present a new test vector compaction algorithm that significantly reduces the number of test vectors. This new algorithm takes advantage of the density and reconfigurability of nanoelectronic circuits by raising the granularity of defect diagnosis to the row/column level. We are therefore able to reduce the number of test vectors to O(n+p) for a PLA with n input and p product lines without sacrificing diagnosability. Experimental results show that our checkpointing scheme, together with the compaction algorithm, tolerates a much higher fault rate than previously possible.
Wireless-compatible CMOS-based celluar sensor

Biosensors have a need to accurately detect and quantify a biological target within a complex medium, such as serum. Cells are uniquely qualified to accomplish this, but cannot communicate with the outside world. We demonstrate a synergistic fusion between a genetically engineered cell line and a wireless-compatible CMOS sensor leveraging the cells innate ability to specifically bind, amplify and transduce the signal with electronics that are capable transforming this cellular signal into an electronic one. We demonstrate the detection of TNF-alpha (TNFα) within serum without washing. Since cells are real-time transducers of binding events, real-time monitoring of biological agents and reactions are possible.
Treading Softly: Paths to Ecological Order . By Thomas Princen

Treading Softly: Paths to Ecological Order . By Thomas Princen. Cambridge, MA: MIT Press, 2010. 224p. $22.95. When you are trying to get someone to embrace new habits of mind and body, like, say, those of ecological sustainability, it sometimes works to appeal to common sense. Thomas Princen employs this stragegy of persuasion—he also invokes enlightened self-interest, but I think he prefers to appeal to common sense—in his bold, tolerant, honest, and powerful short book. To be more specific, he invokes a set of minor or currently rather quiet “segments” (p. 171) inside the mixed bag that is American common sense. Common sense is not, after all, a stable block but a conglomeration of diverse parts, some of which do not fit at all well with the others. And it is the heterogeneity of the common store of wisdom that makes possible Princen's reorganization of it. He highlights some underutilized segments of the “old normal” and harnesses their power to the project of building a society that “takes infinite material growth as impossible,” “embraces limits” (p. 187), and is devoted to “living well by living well within our means” (p. 124).
Evaluation of ZigBee communication platform for controlling the charging of PHEVs at a municipal parking deck

Large penetration of Plug in Hybrid Electric Vehicles (PHEV) poses a potential threat to grid stability if PHEV battery charging is not managed. Thus there is a need of enabling technologies for control of PHEV battery charging. A critical component of such a system is the communication between the PHEV batteries and a central controller which we call the intelligent energy management system (iEMS). In this paper we describe the system architecture with ZigBee as the communication medium, followed by an experimental setup to demonstrate the iEMS with ZigBee communication. Our future work is to measure delay, throughput, received signal strength etc. to characterize the communication link and quantify its effect on iEMS performance.
Neuronal correlates of functional magnetic resonance imaging in human temporal cortex

The relationship between changes in functional magnetic resonance imaging and neuronal activity remains controversial. Data collected during awake neurosurgical procedures for the treatment of epilepsy provided a rare opportunity to examine this relationship in human temporal association cortex. We obtained functional magnetic resonance imaging blood oxygen dependent signals, single neuronal activity and local field potentials from 8 to 300 Hz at 13 temporal cortical sites, from nine subjects, during paired associate learning and control measures. The relation between the functional magnetic resonance imaging signal and the electrophysiologic parameters was assessed in two ways: colocalization between significant changes in these signals on the same paired associate-control comparisons and multiple linear regressions of the electrophysiologic measures on the functional magnetic resonance imaging signal, across all tasks. Significant colocalization was present between increased functional magnetic resonance imaging signals and increased local field potentials power in the 50–250 Hz range. Local field potentials power greater than 100 Hz was also a significant regressor for the functional magnetic resonance imaging signal, establishing this local field potentials frequency range as a neuronal correlate of the functional magnetic resonance imaging signal. There was a trend for a relation between power in some low frequency local field potentials frequencies and the functional magnetic resonance imaging signal, for 8–15 Hz increases in the colocalization analysis and 16–23 Hz in the multiple linear regression analysis. Neither analysis provided evidence for an independent relation to frequency of single neuron activity.
Location of Calcium Within Bacillus Spores by Electron Probe X-Ray Microanalysis

Spectroscopic microanalysis of the element-characteristic X rays produced by a scanning electron microprobe was employed to detect calcium and carbon in both intact and thin-sectioned spores of Bacillus cereus T and B. megaterium QM B1551. Linear scan profiles and multilinear scan images of the X-ray emissions for calcium (Ca(Kalpha)) were compared with those for carbon (C(Kalpha)) as an index of mass. Location was accomplished by stereological comparisons with secondary electron images and conventional transmission electron micrographs. Although the elements could be detected at the attogram level theoretically, spatial resolution was limited to approximately 500 to 1,000 nm in an intact spore, e.g., by the primary electron beam diameter, the electron-excited spore microvolume, and the type of specimen support. The resolution was improved to approximately 100 to 200 nm by use of thin-sectioned spores, with precautions to prevent calcium leakage from the specimen during preparations. In both intact and sectioned spores, calcium was distributed throughout the spore, similarly to carbon, and concentrated mainly in a central region corresponding to the spore protoplast.
Subdiaphragmatic murine electrophysiological studies: sequential determination of ventricular refractoriness and arrhythmia induction.

Programmed electrical stimulation (PES) is a crucial aspect of the evaluation of the risk of arrhythmias in cardiac patients and provides a powerful tool for understanding the mechanisms of arrhyth...
Some comments on research and publication practices and ethics

Pressure has increased on engineering faculties to do more, including publishing. Publication has also become more common as a "ticket" to the proliferating number of meetings being held, where giving a paper is often the only way to ensure attending a meeting. The result has been an apparently substantial increase in the amount of publication by those active in their fields. It has possibly also created a number of associated problems with regard to publication ethics and related issues. This column is the first of two parts, addressed to the general topic of research and publication practices, and ethics. >
A monolithic three‐terminal GaInAsP/GaInAs tandem solar cell

We describe the design and performance of a three-terminal tandem solar cell for low-concentration terrestrial applications. Designed for operation under a GaAs filter, the tandem demonstrates cumulative conversion efficiencies of 10.2 and 11.9% at 1 sun and 45 suns, respectively, under the concentrated direct spectrum. The middle terminal is shared between the two subcells and allows them to be operated independently at their respective maximum power points. Copyright # 2009 John Wiley & Sons, Ltd.