cssi/SciSciGPT-SciSciNet huggingface dataset:
Varenicline enhances dopamine release facilitation more than nicotine after long-term nicotine treatment and withdrawal

An important factor contributing to the high relapse rates among smokers is nicotine withdrawal symptoms. Multiple studies suggest that decreased dopamine release in nucleus accumbens plays a key role in withdrawal. However, recent reports showed that long-term nicotine exposure itself also decreases accumbal dopamine release, suggesting that additional mechanisms are involved in withdrawal. Here, we used real-time cyclic voltammetry in brain slices containing the nucleus accumbens to further elucidate the changes in dopamine release linked to nicotine withdrawal. Rats received vehicle or nicotine via the drinking water for 2–3 months. Studies assessing the expression of somatic signs in vehicle-treated, nicotine-treated, and 24-h nicotine withdrawn rats showed that nicotine withdrawal led to a significant increase in somatic signs. Subsequent voltammetry studies showed that long-term nicotine decreased single-pulse-stimulated dopamine release via an interaction at α6β2* receptors. Nicotine withdrawal led to a partial recovery in α6β2* receptor-mediated release. In addition, long-term nicotine treatment alone increased dopamine release paired-pulse ratios and this was partially reversed with nicotine removal. We then evaluated the effect of bath-applied nicotine and varenicline on dopamine release. Nicotine and varenicline both decreased single-pulse-stimulated release in vehicle-treated, nicotine-treated, and nicotine withdrawn rats. However, bath-applied varenicline increased paired-pulse ratios to a greater extent than nicotine during long-term nicotine treatment and after its withdrawal. Altogether these data suggest that nicotine withdrawal is associated with a partial restoration of dopamine release measures to control levels and that varenicline's differential modulation of dopamine release may contribute to its mechanism of action.
Strong pinning in heat treated YBa2Cu3O7−δ

Abstract A number of authors have discussed the pinning of magnetic fluxoids in high temperature superconductors in terms of a cooperative process involving large numbers of defects. In particular, in a recent study of magnetic flux creep in high quality single crystals of YBa 2 Cu 3 O 7−δ , we showed that an appropriate collective pinning model accurately described the creep in that part of the H-T phase diagram where the creep is controlled by single fluxoid motion. Here we present data on similar crystals given an additional heat treatment at temperatures above 800°C. These crystals exhibit large critical currents that exceed the limit associated with collective pinning, suggesting the influence of strong pinning defects. An analysis of the pinning potential U(j) at large j provides further evidence for strong pinning. We suggest that the heat treatment introduces precipitates of nearly optimum size for pinning, leading to a combination of weak and strong pinning defects.
A new mixed mode fracture test specimen covering positive and negative values of T-stress

A B S T R A C T A new fracture test specimen is suggested and analyzed using finite element method. The mode I and mode II stress intensity factors as well as the T-stress were calculated for three geometries and loading conditions. It is shown that the specimen, called single edge cracked ring (SECR), covers different mixed mode loading conditions from pure mode I to pure mode II. The SECR specimen also covers negative and positive values of T-stresses. From the practical view point, the suggested specimen can be used easily for mixed mode II fracture tests.
Alert propagation in mobile ad hoc networks

Intrusion/misbehavior detection and response are two important components for defending against various attacks in mobile ad hoc networks. Unfortunately, there is a gap between local intrusion/misbehavior detection and network-wide response in such networks. To bridge this gap, alert propagation, aiming to spread alert messages to the whole network upon detection of malicious/abnormal activity, is a viable solution but has been overlooked.
Injectable in situ Physically and Chemically Crosslinkable Gellan Hydrogel

An injectable, in situ physically and chemically crosslinkable gellan hydrogel is synthesized via gellan thiolation. The thiolation does not alter the gellan's unique 3-D conformation, but leads to a lower phase transition temperature under physiological conditions and stable chemical crosslinking. The synthesis and hydrogels are characterized by (1)H NMR, FT-IR, CD, or rheology measurements. The injectability and the tissue culture cell viability is also tested. The thiolated gellan hydrogel exhibits merits, such as ease for injection, quick gelation, lower gelling temperature, stable structure, and nontoxicity, which make it promising in biomedicine and bioengineering as an injectable hydrogel.
Infant Brain Responses to Object Weight: Exploring Goal-Directed Actions and Self-Experience.

Recent work has suggested the value of electroencephalographic (EEG) measures in the study of infants’ processing of human action. Studies in this area have investigated desynchronization of the sensorimotor mu rhythm during action execution and action observation in infancy. Untested but critical to theory is whether the mu rhythm shows a differential response to actions which share similar goals but have different motor requirements or sensory outcomes. By varying the invisible property of object weight, we controlled for the abstract goal (reach, grasp, and lift the object), while allowing other aspects of the action to vary. The mu response during 14-month-old infants’ own executed actions showed a differential hemispheric response between acting on heavier and lighter objects. EEG responses also showed sensitivity to “expected object weight” when infants simply observed an experimenter reach for objects that the infants’ prior experience indicated were heavier vs. lighter. Crucially, this neural reactivity was predictive—during the observation of the other reaching toward the object, before lifting occurred. This suggests that infants’ own self-experience with a particular object’s weight influences their processing of others’ actions on the object, with implications for developmental social-cognitive neuroscience.
Breaking the Bonds of Precedent: The 1905–6 Government Reform Commission and the Remaking of the Qing Central State

On January 29, 1901, in the grim aftermath of the Boxer Uprising and the humiliating foreign invasion of north China that followed, the Empress Dowager Cixi issued a famous edict that initiated the New Policy (xinzheng) reforms.The weakness of China is caused by the strength of convention and the rigid network of regulations. We have many mediocre officials but few men of talent and courage. The regulations are used by mediocre men as the means of their self-protection, and taken advantage of by government clerks as sources of profit. The government officials exchange numerous documents but they never touch reality. The appointment of capable men is restricted by regulations so rigid that even men of exceptional talent are missed. What misleads the country can be expressed in one word, selfishness, and what suffocates all under heaven is precedent.
Ultrafast Energy Transfer and Strong Dynamic Non-Condon Effect on Ligand Field Transitions by Coherent Phonon in γ-Fe2O3 Nanocrystals

Relaxation dynamics of an optically excited ligand field state and strong modulation of oscillator strengths of ligand field transitions by coherent acoustic phonon in γ-Fe2O3 nanocrystals were investigated through transient absorption measurements. A near-infrared pump beam prepared the lowest excited ligand field state of Fe3+ ions preferentially on the tetrahedral coordination site. A time-delayed visible probe beam monitored the dynamics of various ligand field transitions and modification of their oscillator strengths by a coherent lattice motion. Transient absorption data exhibited dynamic features of a few distinct time scales, 100 fs, 1 ps, and 17−100 ps, as well as intense oscillatory features resulting from a coherent acoustic phonon. The initial decay of the induced absorption in 100 fs has been attributed to the exchange interaction-mediated energy transfer from the tetrahedral to octahedral Fe3+ sites. The dynamics of slower time scales were assigned to the vibrational and electronic relaxati...
Investigating the effect of dehydration conditions on the compactability of glucose.

Abstract Hydrates are commonly found in pharmaceutical ingredients either in excipients or in the active pharmaceutical ingredient form. There is always the possibility that the processing involved in manufacturing can result in the dehydration of the hydrate components. It has been seen that different dehydration conditions can have an effect on the behavior of the final product; however this area has not been fully investigated. In this work, glucose monohydrate powder was dehydrated at four different conditions and then compressed to see the effect on the hardness of the compacts. Various analytical tools such as inverse gas chromatography, differential scanning calorimetry, X-ray powder diffractometry and scanning electron microscopy were used to determine any differences in the properties of the dehydrates and correlated with the obtained compact hardness. Annealing studies were performed to determine the effect of storage on the dehydrated materials both before and after compression. It was observed that while annealing of the powders did have an impact, annealing of the compacts did not influence the hardness. The results of the characterization and annealing studies showed that the difference in the behavior of glucose dehydrates were due to the presence of amorphous regions within the particulates.
Life of silicon carbide heaters in argon at high temperatures

The electrical heating elements made from silicon carbide in argon age slowly and may operate for more than 300 h at a temperature on the surface of 1700‡C and more than 200 h at 1800‡C.
3H-flunitrazepam binding to bovine retina and the effect of GABA thereon

Abstract Bovine retinae were examined for their ability to bind 3 H-flunitrazepam. Whole retinal homogenates revealed specific, high affinity, and saturable 3 H-flunitrazepam binding (K d , 1.1 nM; B max , 19.5 fmoles/mg tissue). In washed membrane preparations, 10 μM GABA caused a dramatic decrease in the K d (42 percent). The rank order of potency for the inhibition of 3 H-flunitrazepam binding by different benzodiazepines was: clonazepam > clobazam ⪢ Ro 5-4864. These results are supportive for the presence of benzodiazepine receptors in the bovine retina and indicate a likeness with the previously described benzodiazepine receptors of mammalian brain.
A Charmed Brew: Document Delivery and Collection Development in the Fast Lane

As we choose between on- site document delivery services or remote services and attempt to evaluate types of access available, costs involved, turn-around time, ease of order placement, delivery options, frequency of update, and technical support provided, we have created for ourselves not only a charmed brew, but as Ronald Leach says, "an electronic tower of Babylon."[5] Confused? Where does the confusion lie? Not only must we choose between the services I just mentioned, but we need to decide on the system and mode of delivery as well! Will we use fax, or how about Federal Express, Overnight Courier, United Parcel Service, Next Day Air, and please don't forget Second Day Air. The option of electronic scanning also exists, and for some, Ariel is the answer, where a scanned fax is sent over the Internet. Article discusses these and other decisions.
Quasi-one-dimensional numerical simulation of magnetoplasmadynamic thrusters

Magnetoplasmadynamic (MPD) thrusters are a promising method of propulsion for a variety of space missions. This research develops and analyzes a numerical simulation of a quasi-one-dimensional model of a MPD thruster. A finite-difference scheme is used to integrate the governing equations. These equations allow for separate heavy species and electron temperatures and a variable nonequilibrium ionization fraction, and they can be expanded to allow for velocity slip between neutrals and ions. The model includes source terms used to represent collisional energy transfer between species, viscosity, and ambipolar diffusion, electron heat conduction, and the effects of velocity slip. Solutions to the governing equations were found for a range of cases and geometries, including different source terms in order to determine their effect on the thruster flow. These results show that thermal equilibrium is not a valid assumption in a typical MPD thruster, that viscosity and velocity slip can greatly influence heavy species temperature, and that viscosity and area variation play a significant role in determining thruster performance. Finally, good agreement is found with experimental thrust measurements, but not with operating voltage measurements.
Top-down attention switches coupling between low-level and high-level areas of human visual cortex

Top-down attention is an essential cognitive ability, allowing our finite brains to process complex natural environments by prioritizing information relevant to our goals. Previous evidence suggests that top-down attention operates by modulating stimulus-evoked neural activity within visual areas specialized for processing goal-relevant information. We show that top-down attention also has a separate influence on the background coupling between visual areas: adopting different attentional goals resulted in specific patterns of noise correlations in the visual system, whereby intrinsic activity in the same set of low-level areas was shared with only those high-level areas relevant to the current goal. These changes occurred independently of evoked activity, persisted without visual stimulation, and predicted behavioral success in deploying attention better than the modulation of evoked activity. This attentional switching of background connectivity suggests that attention may help synchronize different levels of the visual processing hierarchy, forming state-dependent functional pathways in human visual cortex to prioritize goal-relevant information.
A computational study of the impingement region of an unsteady subsonic jet

Vertical/Short Take-Off and Landing (V/STOL) aircraft may encounter operating difficulties while hovering near the ground. Lift loss, hot gas and debris ingestion, and landing surface damage are some of the potential problems which can result from the interaction of the propulsive jets with the airframe and ground. The purpose of the present work is to develop a detailed understanding of a flowfield, a jet exiting from a flat plate impacting a ground plane, that contains much of the essential physics of the complex flows encountered by V/STOL aircraft in hover. To achieve this, a high-resolution time-accurate numerical simulation of the impinging jet flow was performed. The numerical simulation is based on the solution of the laminar compressible Navier-Stokes equations using the Beam-Warming algorithm. Complex start-up and periodic jet and jet-induced vortex structures were captured, including the formation of primary and secondary jet-induced vortices and wall-jet separation. The formation and development of these phenomena are supported by experimental measurements and smoke visualization. Results are compared with appropriate experiments.
Attachment of nascent RNA molecules to superhelical DNA.

Comparisons are made of the attachment of nascent RNA molecules synthesized in vitro with Escherichia coli RNA polymerase on native bacteriophage PM2 DNA, a double-helical circular DNA with −110 superhelical twists, and on a derivative of this DNA with no superhelical twists. When RNA synthesis is terminated on either DNA by adding EDTA to chelate the Mg2+ ions, the nascent (incompletely polymerized) RNA chains remain bound to the DNA by bonds that involve fewer than 20 nucleotides of the RNA molecule. Differences between the two kinds of DNA are found when the complexes with nascent RNA are treated with sodium dedecyl sulfate or other agents that dissociate proteins (e.g. 3 m -CsCl; 5 m -urea; phenol). With such treatments, all RNA is released from the non-superhelical DNA, whereas only 40% of the RNA molecules are released from the superhelical DNA. The other 60% become bound even more tightly to that DNA, apparently by means of a hybrid helix that can involve up to 600 nucleotides of the bound RNA. It is suggested that the hybrid helix forms spontaneously on the superhelical DNA after denaturing the enzyme because the unwinding of the DNA helix needed to create the RNA-DNA helix relieves some of the strain that is known to exist in the superhelical DNA. Since the extensive hybrid helix does not exist before adding the detergent, the intact structure of the enzyme appears to be important to prevent its formation. Evidently RNA polymerase has a site that dissociates the polymerized portion of the RNA from the DNA as the enzyme moves along the template.
The Z = 0.8596 Damped LY alpha Absorbing Galaxy toward PKS 0454+039

We present Hubble Space Telescope (HST) and ground-based data on the Z(sub abs) = 0.8596 metal-line absorption system along the line of sight to PKS 0454+0356. The system is a moderate-redshift damped Ly-alpha system, with N(H I) = (5.7 +/- 0.3) x 10(exp 20)/sq cm as measured from the Faint Object Spectrograph (FOS) spectrum. We also present ground-based images which we use to identify the galaxy which most probably gives rise to the damped system; the most likely candidate is relatively underluminous by QSO absorber standards M(sub B) approximately -19.0 for A(sub 0) = 0.5 and H(sub 0) = 50 km/s/Mpc) and lies approximately 8.5/h kpc in projection from the QSO sight line. Ground-based measurements of Zn II, Cr II, and Fe II absorption lines from this system allow us to infer abundances of (Zn/H) = -1.1, (Cr/H) = -1.2, and (Fe/H) = -1.2 indicating overall metallicity similar to damped systems at z is greater than 2, and that the depletion of Cr and Fe onto dust grains may be even less important than in many of the high-redshift systems of comparable metallicity. Limits previously placed on the 21 cm optical depth in the z = 0.8596 system, together with our new N(H I) measurement, suggest a very high spin temperature for the H I, T(sub s) is greater than 580 K.
Putative non-reciprocal crossing over in Drosophila melanogaster.

1. From ⧫⧫ heterozygous for the mutantswa/wa4white-eyed progeny are recovered in association with crossing over. On the basis of the marker gene distribution to the white-eyed exceptions, the left segment of theirw locus comes from thewa4chromosome, the right segment from thewachromosome. 2. No exceptions reciprocal to the white-eyed exceptions were found. 3. Evidence is presented which demonstrates that the white-eyed exceptions are associated with a cytologically undetectable loss. 4. The occurrence of the white-eyed exceptions is dependent not on thewamutant but rather on tightly linked factors to the right ofwa. 5. It is suggested that the white-eyed exceptions occur as a consequence of crossing over within not strictly homologusly paired component segments of thewhite region of the chromosome.
Gonococcal Endocarditis: Twenty-Five Year Experience

Gonococcal endocarditis is a devastating albeit rare complication of disseminated gonorrhea. It virtually disappeared as a disease entity with the advent of antibiotic therapy. Recently, it has reappeared with surprisingly high frequency for unclear reasons. Since 1983, the authors have observed six episodes of this disease in five patients, the largest series reported to date. It is predominantly a disease of young people without underlying valvular heart disease. Characteristic clinical features include a high frequency of congestive heart failure and nephritis and a proclivity for aortic valve involvement, commonly with associated ring abscess, and large vegetations. Genitourinary symptoms, arthralgias, and rash are uncommon. Previously undescribed features include involvement of all four valves simultaneously, recurrence on an aortic valve prosthesis, and a high frequency of terminal complement deficiencies. Precipitous hemodynamic deterioration despite appropriate therapy is not uncommon, and overall mortality rate remains an alarming 19%.
Correlation bags, vibrons, and strong correlation fluctuations in the copper oxides

Two equilibrium Cu-O bond lengths coexist in the superconductive CuO2 sheets of the high Tc copper oxides because of a discontinuous change in the volume of localized and delocalized electrons at a cross-over from localized to itinerant electronic behavior. Cooperative bond-length segregation and a progressive ordering of the two bond lengths with decreasing temperature result. Transformation from local fluctuations to long- range order in a traveling charge- density wave occurs at a critical point Tcrit≈Tc for a hole concentration x≈ 1/6 per Cu atom in the superconductive CuO2 sheets. Extensive experimental evidence for the model is cited.
Value of Dobutamine Stress Echocardiography in Determining the Prognosis of Patients With Known or Suspected Coronary Artery Disease

Abstract Although the accuracy of dobutamine stress echo (DSE) for detecting coronary artery disease (CAD) has been established, its role in determining prognosis is less well defined. The purpose of this study was to evaluate the prognostic significance of DSE in patients with known or suspected CAD. Follow-up was obtained on 291 patients an average of 15 months after clinically indicated DSF. Studies were stratified with respect to resting and inducible wall motion abnormalities into 1 of 4 responses: normal, ischemic, fixed, and mixed. Hard end points of nonfatal myocardial infarction and cardiac death were tabulated for outcome. Statistically significant differences in the incidence of hard cardiac end points were noted for 2 of 4 DSE responses. A normal DSE was associated with a statistically lower likelihood of a hard cardiac event than was a DSE demonstrating resting or inducible abnormalities (p = 0.001). DSE with a mixed response (resting abnormality with additional inducible ischemia) was associated with a higher likelihood of cardiac events by multivariate analysis (p = 0.003). By multiple logistic regression analysis of dobutamine response, age, and cardiac risk factors, only a mixed response on DSE was independently associated with the occurrence of a hard cardiac event in the follow-up period. In addition, left ventricular dysfunction on the resting echocardiogram was associated with a worse prognosis in patients with major noncardiac disease. We conclude that dobutamine response is an independent predictor of cardiac events compared with traditional risk factor analysis and that DSE can identify high- and low-risk subsets of patients with known or suspected CAD. (Am J Cardiol 1996;78:404–408)
The ethic of care: leisure possibilities and constraints for women.

Abstract The purpose of this paper is to provide a review and an interpretive framework for examining the “ethic of care” (i.e., the activity of relationships) as it offers possibilities and constraints for the leisure of women. The explanatory implications of the ethic of care are useful in further understanding antecedent and intervening constraints to leisure as well as understanding the empowering possibilities of leisure for women. The paper uses a feminist framework to address the concept of an ethic of care, the ways that the ethic has been embodied in leisure behavior for women primarily within the family, the link between an ethic of care and constraints to leisure for women, and the possibilities for the value of an ethic of care in the leisure of all individuals. In describing the experiences of women, the ethic of care is not meant to further dichotomize males and females in leisure but to offer an explanation of women's leisure and to provide some ideas that require further empirical research.
Intravascular ultrasound imaging of saphenous vein graft stenosis.

Abstract Coronary angiography has been used as a gold standard for assessing the results of such interventional procedures as balloon angioplasty, atherectomy and laser angioplasty. However, it is still imprecise in defining the extent and composition of atheromatous plaques, and can underestimate the severity of disease process in an eccentric lesion. 1,2 The introduction of intravascular ultrasound as an imaging modality for atherosclerotic coronary artery disease has opened a new field for studying the morphologic changes before and after interventional procedures. Because of the incorporation of high-frequency transducers, it is possible to obtain images of the coronary arterial wall and assess the structural composition of the diseased segments. 3–5 With the increasing number of procedures and devices being developed currently to deal with atherosclerotic obstruction, there is a need for a technique that will permit accurate assessment of alterations in the luminal area, integrity of the intimal surface, and the presence or absence of ulcerated plaques and thrombi. The present study describes our initial experience in using intravascular ultrasound to evaluate stenosed saphenous vein grafts undergoing angioplasty.
Isolation and identification of lanosterol as a normal constituent of the lipids of the free living nematode Panagrellus redivivus

Abstract 1. 1. The lipids of the free-living nematode Panagrellus redivivus were examined for C30 triterpenes. 2. 2. The common sterol precursor lanosterol was identified as a constituent of the lipids of Panagrellus redivivus.
Evolutionary analysis ofα andβ hemoglobin genes by REH theory under the assumption of the equiprobability of genetic events

It is shown how REH theory in conjunction with mRNA or gene sequence data can be used to obtain estimates of the fixation intensity, the number of varions, and the total mutations fixed between homologous pairs of nucleic acids. These estimates are more accurate than those that can be derived from amino acid sequence data. The method is illustrated forα andβ hemoglobin genes and these improved estimates are compared with those made from the amino acid sequences for which those genes code. Significant differences are found between the estimates made by these two methods. For theβ hemoglobin gene sequences examined here, the fixation intensity is some-what less than the protein data had suggested, and the number of rations is considerably greater. Depending on the gene sequences examined, between 62 and 83% of the codons appear able to fix mutations during the divergences considered. This reflects the constraints of natural selection on acceptable mutations. The total number of base replacements separating the genes for human, mouse, and rabbitβ hemoglobin varies from 61 to 105 depending on the pair examined. Rabbitα andβ hemoglobin are separated by at least 290 fixed mutations. For such distantly related sequences estimates made from protein and mRNA data differ less, reflecting the higher quality of information from the many observed changes in primary structure. The effects of nonrandom gene structure on these evolutionary estimates and the fact that various genetic events are not equiprobable are discussed.
UNDEREMPLOYMENT, GENDER, AND LIFE COURSE: WOMEN ATTORNEYS AND COPING STRATEGIES FOR PARENTHOOD

This article focuses on a group of women attorneys launched on careers that are interrupted for shorter or longer periods by the birth of children. Small samples are used for illustration but studied in depth they provide a micro‐level view of employment patterns that are reported in aggregate statistics or the macro level. This article adds gender to the matrix of employment patterns and professional careers. Voluntary underemployment, negotiated for women attorneys, may be a strategy to cope with high demands and limited structural accommodations to those demands.
Inhibition of rat liver catechol-O-methyltranferase by lanthanum, neodymium and europium

Abstract Partially purified rat liver catechol- O -methyltransferase (COMT) is inhibited by lanthanum, and by the lanthanides, neodymium and europium. The 50 per cent inhibitory concentrations are 3 × 10 −6 , 1.2 × 10 −6 , and 8.5 × 10 −7 M for La 3+ , Nd 3+ and Eu 3+ respectively. The inhibition of COMT by these ions is reversible. Lineweaver-Burk plots of the results of experiments in which the enzyme activity was measured in the presence of varying concentrations of magnesium, an activator of COMT, and different concentrations of La 3+ , Nd 3+ and Eu 3+ were compatible with non-competitive or “mixed” inhibition. Double reciprocal plots of the results of experiments in which COMT activity was determined in the presence of different concentrations of La 3+ and varying quantities of the two co-substrates for the reaction, S -adenosyl-1-methionine and 3,4-dihydroxybenzoic acid, were also compatible with non-competitive or “mixed inhibition”. The characteristics of the inhibition of rat liver COMT by La 3+ , Nd 3+ and Eu 3+ are similar to those of the inhibition of COMT by Ca 2+ . However, lanthanum, neodymium and europium are two to three orders of magnitude more potent inhibitors of COMT than is calcium.
The lizard ear: Scincidae†

Observations on inner ear structure were made in five species of Scincidae, together with measurements of auditory sensitivity in terms of cochlear potentials. The basilar membrane and auditory papilla show a characteristic form, with considerable uniformity in dimensions except for a moderate expansion in the dorsal region and a more prominent one at the ventral end. A characteristic feature is the presence of a tectorial membrane that covers a large part of the surface of the medial limbus, but never leaves this surface and thus fails to make any contact with the auditory papilla. Hair-cell stimulation is achieved entirely through operation of the inertia principle (or equivalent principles) by means of a chain of sallets extending along most of the cochlea but giving way in the region of the ventral expansion to a single large body, the culmen papillae. The sensitivity varies in the five skinks studied from better than average to some-what below average in comparison with other lizard species. Thus an inertial (or inertia-like) system of hair-cell stimulation compares favorably with the tectorial membrane (restraint) system exhibited in the ears of most other lizards and all the higher animals.
Walking in the Shadows of the Past: The Jewish Experience of Rome in the Twelfth Century

The Jewish and Christian inhabitants of twelfth-century Rome viewed the urban landscape of their city through the lens of its ancient past. Their perception of Rome was shaped by a highly localized topography of cultural memory that was both shared and contested by Jews and Christians. Our reconstruction of this distinctively Roman perspective emerges from a careful juxtaposition of the report of Benjamin of Tudela’s visit to Rome preserved in his Itinerary and various Christian liturgical and topographical texts, especially those produced by the canons of the Lateran basilica. These sources demonstrate that long-standing local claims regarding the presence in Rome of ancient artifacts from the Jerusalem Temple and their subsequent conservation in the Lateran acquired particular potency in the twelfth century. Jews and Christians participated in a common religious discourse that invested remains from the biblical and Jewish past reportedly housed in Rome with symbolic capital valued by the two communities and that thus fostered both contact and competition between them. During this pivotal century and within the special microcosm of Rome, Jews and Christians experienced unusually robust cultural and social interactions, especially as the Jews increasingly aligned themselves with the protective power of the papacy.
Protein-Induced Shape Changes in Phase-Separated Vesicles

We explore changes in curvature in vesicles composed of a mixture of phospholipids and cholesterol upon the binding of protein to the membrane. Experiments were done with model peptides and with members of the BAR family of proteins. Vesicles were prepared using electroformation with a mix of phosphatidylcholine, cholesterol, and sphingomyelin. As a sample is lowered through temperature Tmix, a homogeneous vesicle phase separates into two fluid phases with distinct compositions. A line tension at the boundary between the phases deforms the membrane, producing buds with a shape determined by a balance of membrane and line tension. Green fluorescent protein (GFP) with a 6X histidine tag was added to the solution, where it bound to Ni-chelating phospholipids present in the membrane at concentrations ranging from 0.1 to 5 mol%. Domain budding was recorded before and after GFP addition using both differential interference and fluorescence microscopy. Analysis of the shape of the vesicle before and after addition of GFP allows for the determination of the change in line tension owing to the GFP binding. Similar results were obtained with vesicles introduced to poly-L-histidine. A possible mechanism for the change in shape seen with both GFP and poly-L-histidine binding is formation of protein-Ni-chelating lipid complexes that sit at the boundary between phases and lower the line tension. Preliminary investigations into shape changes caused by BAR domains of Drosophila amphiphysin revealed fine vesicle tubulation that initiated at the boundary between the two lipid phases. The addition of both model proteins (GFP and poly-L-histidine) and biologically relevant protein (BAR domains) into our system allows for a broader understanding of the effect of protein, which are ubiquitous in cell membranes, on phase separation and budding.NSF IGERT Program in NanotechnologyUmass Biomedical Innovation Initiative
Transcranial Doppler ultrasound following closed head injury: vasospasm or vasoparalysis?

Abstract Nine patients suffering closed head injury were studied using transcranial Doppler ultrasound recording of the basal cerebral arteries. On admission, six patients had Glasgow Coma Scores of 7 or less, while three had initial scores of 8-10. Eight of the nine patients (82%) developed abnormally high mean velocities (≥110 cm/s) in one or more vessels. The onset, duration, and amplitude of the altered flow velocities were somewhat different from those that are seen with vasospasm after aneurysmal subarachnoid hemorrhage, which tend to occur later. Cerebral angiography in one of the study patients confirmed the presence of vasospasm. Multivariate regression analysis showed a definite correlation between the velocities recorded, even when abnormally elevated, and concurrent pH and P CO 2 measurements ( p = 0.01, R 2 = 0.23). Although these results suggest that the cerebral vasculature retains its vasoreactivity following head injury, arguing against vasoparalysis, inconsistencies found in some of the patients lead us to think that both vasospasm and vasoparalysis may occur following head trauma but that they may have different temporal profiles.
Deletion of dnaN1 generates a mutator phenotype in Bacillus anthracis

The dnaN gene in eubacteria is an essential gene that encodes the β subunit of replicative DNA polymerase. Nearly all eubacterial genomes sequenced to date predict a single copy of the dnaN gene in a well-conserved neighboring gene context. However, 19 genomes out of 348 scanned, including Bacillus anthracis, Bacillus cereus, Bacillus thuringiensis, and Bacillus weihenstephanensis, predict more than one dnaN gene. In most cases, these genomes appear to maintain a copy of the dnaN homolog in its usual neighboring gene context (designated as dnaN1) in addition to a second copy (designated as dnaN2) in an entirely different gene context. We used B. anthracis as our model system to investigate the role of these DnaNs. We constructed a single knockout mutant of dnaN1 and of dnaN2; however, we could not make a viable double knockout mutant of dnaN1 and dnaN2. The dnaN1 knockout mutant displays a markedly reduced colony size. It also displays a significantly increased mutation rate, which is similar to that of a mismatch repair deficient strain and to a strain deficient both in dnaN1 and mismatch repair. The dnaN2 knockout mutant, however, has a similar growth rate and a comparable mutation rate to that of the wild type. This is the first study demonstrating the existence of two functional DnaN homologs in the B. anthracis genome, with DnaN1 appearing to be more crucial than DnaN2. Our results also suggest the direct involvement of DnaN1 in the DNA mismatch repair process, which is consistent with previous findings.
The effect of Backbone cyclization on the thermodynamics of β-sheet unfolding: Stability optimization of the PIN WW domain

Backbone cyclization is often used in attempts to enhance protein stability, but is not always successful as it is possible to remove stabilizing or introduce destabilizing interactions in the process. Cyclization of the PIN1 WW domain, a 34-residue three-stranded β-sheet structure, removes a favorable electrostatic interaction between its termini. Nevertheless, optimization of the linker connecting the N- and C-termini using information based on the previously determined ensemble of NMR structures leads to β-sheets that are more stable than those derived from the linear sequence. Linkers that are too short or too long introduce strain, likely disrupting native interactions, leading to cyclic folds that are less stable than that of the linear sequence.
Thermally-induced soft errors in nanoscale CMOS circuits

Electrical noise will play an increasingly critical role in future nanoscale CMOS circuit operation character ized by lower supply voltages VDD and smaller device sizes. Both of these downscaling approaches reduce the margin of immunity to thermal noise, alpha particle strikes, and threshold voltage variations. This paper investigates the noise probability distributions for both equilibrium and non-equilibrium logic states of advanced CMOS flip-flops operated at ultra-low VDD. The theoretical distribution of transition times from one stable operation point to the other stable operation point is also der ived, which is a useful representation of the soft error rate. It is shown that such nanoscale flip-flop designs are extremely sensitive to threshold variations, reducing average failure time to a few days. Monte Carlo simulations are provided to validate the theoretical model and its predictions.
Continuous-flow devices and percutaneous site infections: clinical outcomes.

Background Although continuous-flow left ventricular assist device (LVAD) support has become standard therapy, the complexities of device and patient management remain a challenge. In particular, percutaneous site infections (PSI) are a serious complication during the post-implant course. We sought to study the incidence, risk factors, and clinical effect of PSI. Methods Data were obtained from the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) Registry. All adult patients who received a primary intracorporeal continuous flow LVAD between June 2006 and September 2010 were included. Descriptive statistics, Kaplan-Meier depictions, and multivariable analysis in the parametric hazard domain were used for statistical analysis. Results A total of 239 PSIs were documented in 197 of 2,006 recipients (9.8%) of a continuous-flow LVAD. Mean follow-up was 8.1 months. Mean time to development of a PSI was 6.6 months. At 1 year after implant, nearly 19% of continuous-flow LVAD recipients developed a PSI. Multivariate analysis showed younger age (hazard ratio, 1.20; p p = 0.004). Twenty-three patients died after development of a PSI. Sepsis was the most common cause of death (26.1%). Conclusions PSIs occur in approximately 19% of continuous-flow LVAD recipients by 12 months after implant. Young age is the only predictor of PSI. Importantly, development of a PSI adversely affects survival. Efforts to enhance driveline integration and to develop future totally implantable systems are warranted.
Heuristic evaluation of user interface for point-of-care diagnosis and rehabilitation of mild Traumatic Brain Injury

Clinical assessment systems deployed in rehabilitation settings are likely to consist of several software and hardware components that subjects directly interact with. While it is extremely important that all facets of user interface are tested for critical ergonomic issues, it may be useful to identify those issues during the design and development of the system. In this paper, we present a point-of-care research prototype that is being developed to assist with diagnosis and rehabilitation of upper-limb motor deficits in mild Traumatic Brain Injury (TBI) patients. The aim of this paper is to describe the application of heuristic evaluation to expose user interface problems during the development process. Results from a participatory model of heuristic evaluation are used to highlight the utility of this usability method in clinical engineering especially, in designing medical devices.
Abstract IA9: The MEK network as a target for combination therapies

Small molecule inhibitors of signal transduction pathways can elicit complex and sometimes non-intuitive molecular responses in cancer cells. Increasing evidence supports the notion that these responses are important mediators of de novo drug resistance. We systematically assessed molecular and cellular responses to MEK inhibitors, aiming at identifying meaningful targets for combination therapies. Proteomic analyses revealed an EGFR-dependent feedback loop resulting in activation of the PI3 kinase pathway following MEK inhibition. In agreement with this, combinations of MEK inhibitors and inhibitors of EGFR inhibitors or PI3 kinase show synergistic effects on cell proliferation and apoptosis rates in molecularly defined disease subtypes. To further explore molecular networks affected by MEK inhibition, Bayesian network inference algorithms were applied and reverse-engineered networks were generated that are amenable to in silico forward-simulation. Using this technology, new, MEK-dependent, novel regulators of cell cycle and apoptosis were identified and experimentally validated. These findings highlight the potential of mathematical modeling approaches to efficiently reveal new and therapeutically relevant features of signal transduction networks.
Utility of the bladder flap at cesarean delivery: a randomized controlled trial.

OBJECTIVE: To test the hypothesis that omission of the bladder flap in primary and repeat cesarean deliveries shortens operating time without increasing intraoperative and postoperative complications. METHODS: We randomized 258 women undergoing primary and repeat cesarean deliveries at 32 weeks of gestation or more to creation (n=131) or omission (n=127) of the bladder flap. Emergency cesarean deliveries, planned vertical uterine incisions, and previous abdominal surgeries besides cesarean deliveries were excluded. The primary outcome measure was total operating time. Secondary outcomes were bladder injury, incision-to-delivery time, incision-to-fascial closure time, estimated blood loss, postoperative microhematuria, postoperative pain, hospital days, endometritis, and urinary tract infection. Analysis followed the intention-to-treat principle.
Object-oriented hypermedia support systems

The autors explore the integration of three software technologies, hyper-navigational user control, multimedia, and object-orientation, to develop more responsive support systems. The merger of these technologies gives rise to a visionary hybrid system type referred to as hypermedia support systems (HSSs). HSSs promote higher levels of understanding because users can interact with rich data types-video, audio, text, and graphics-and approach information from different points of view. Hyper-navigation parallels the associative memory model proposed by cognitive psychologists to represent the human thinking process. As such, hyper-navigation gives users the ability to access information in an intuitive and flexible manner, thereby supporting even unstructured problem solving. Incorporating multimedia technology further increases responsiveness by combining different media elements for display and control from a PC. An object-oriented approach coupled with special objects called software topics provides an integrating mechanism for HSSs. >
Race, Sex, and the U.S. Working Class.

The classical and neo-Marxist theories of the relationship between capitalism and racism and sexism are briefly examined. The predictions of each theory concerning trends in racial and sexual discrimination in the labor force are discussed. While classical Marxist theory predicts a diminishing of racial and sexual barriers, neo-Marxist theory predicts their continuance. Census data are brought to bear on the question in order to test the two theories. Discrimination according to race and sex is measured by the occupational distribution of the races and sexes, the trends in income within each occupation, and the educational level in each occupation. Trends are observed over the period 1940 to 1970. It is found that the classical Marxist prediction of increasing racial homogeneity in the working class is borne out by the data, but that the neo-Marxist prediction of continuing sexual discrimination is also confirmed. A tentative explanation of the divergent tendencies by race and sex is offered. It is suggested that a sexual division of labor is being maintained because of a differential need of the corporations for masculine and feminine personality traits in its labor force. The pressure to keep white wages down, on the other hand, has probably been the major factor leading to the authentic integration of blacks into most levels of the work force.
Oral Epithelial Cell Responses to Multispecies Microbial Biofilms

This report describes the use of a novel model of multispecies biofilms to stimulate profiles of cytokines/chemokines from oral epithelial cells that contribute to local inflammation in the periodontium. Streptococcus gordonii (Sg)/S. oralis (So)/S. sanguinis (Ss) and Sg/Fusobacterium nucleatum (Fn)/Porphyromonas gingivalis (Pg) biofilms elicited significantly elevated levels of IL-1α and showed synergistic stimulatory activity compared with an additive effect of the 3 individual bacteria. Only the Sg/Actinomyces naeslundii (An)/Fn multispecies biofilms elicited IL-6 levels above those of control. IL-8 was a primary response to the Sg/An/Fn biofilms, albeit the level was not enhanced compared with a predicted composite level from the monospecies challenges. These results represent some of the first data documenting alterations in profiles of oral epithelial cell responses to multispecies biofilms.
Learner corpus analysis and the development of foreign language proficiency

Abstract This paper makes a methodological contribution to the emerging field of learner corpus analysis [Granger, S., 1998. Learner English on Computer. Longman, London, 1998; Granger, S., 2002. Computer Learner corpora, Second Language Acquisition, and Foreign Language Teaching. John Benjamins, Amsterdam, 2002] and to Second Language Acquisition (SLA) research by suggesting that a corpus of learner and expert speaker correspondence, in conjunction with ethnographic data, may facilitate microgeneses of particular elements of the foreign language (FL) under study. On the basis of a 100,000-word corpus of telecollaborative correspondence, chronological pathways of da -compound use by learners of German are examined. Telecollaboration involves the use of global computer networks to link expert speakers and learners of particular languages for the purposes of social interaction and academic discussions over a limited period of time within an institutionalized setting.
Climate change in the Lake Valencia Basin, Venezuela, 12600 yr BP to present

We present a palaeoclimate record for northern South America, extending from the latest Pleistocene (~12600 14C yr BP) to present. Climate reconstruction for the Valencia Basin, Venezuela, was base...