cssi/SciSciGPT-SciSciNet huggingface dataset:
Sample and probe: a novel approach for identifying development-specific cis-elements of the enkephalin gene.

We have developed a novel 'sample and probe' approach as a means to identifying specific DNA elements of the enkephalin gene that control differentiation of the enkephalinergic phenotype during neurodevelopment. The approach is a systematic spatiotemporal analysis of protein-DNA interactions; soluble nuclear proteins ('samples') prepared from microdissected regions of the developing brain are 'probed' with radiolabeled DNA fragments representing various regulatory regions of the enkephalin gene. The resulting spatiotemporal 'molecular maps', i.e. characteristic patterns of protein-DNA complexes showed DNA regions that harbor potential cis-elements regulating differentiation of the enkephalin phenotype at various stages of neurodevelopment. DNase I footprint analysis of such a DNA region identified a binding site (GACGGGAGATCGCTCGT) which is similar to the motif for a lymphoid-specific, developmentally regulated transcription factor, Ikaros, suggesting that the developing brain expresses Ikaros-like transcription factor(s) in a spatiotemporally defined manner. In summary, our approach offers a unique view into the chronology of coordinated protein-DNA interactions and will greatly facilitate identifying DNA elements and isolating development-specific transcription factors.
The sustainability assessment of the National Aquaculture Strategy for Cameroon

It is widely accepted that aquaculture initiatives in sub-Saharan Africa have failed to deliver benefits to society in the long run. Development of new national aquaculture strategies (NAS) is thus a common approach. In this study, we interviewed 21 key stakeholders, and a sustainability checklist consisting of 68 questions was applied to the NAS for Cameroon to understand to what extent it mainstreams sustainable development principles. The NAS assessed clearly defines the respective roles of the public and private sectors. Nevertheless, there are several shortcomings that could impede its sustainability and that of a subsequent aquaculture development plan.
The mechanical properties of an Al2O3/Ni3Al particulate-reinforced composite

Abstract The effects of temperature and thermal exposure on the mechanical properties and failure behavior of a nickel aluminide (Ni 3 Al) (IC-221) reinforced with Al 2 O 3 particulates were investigated. The high temperature specific yield strength of the composite was higher than the unreinforced matrix at all the temperatures tested. An increase as high as 40% was exhibited. However, only a slight improvement in specific modulus was observed at room temperature. The composite demonstrated near 100% strength retention after thermal exposures at 100 °C. Specimens with diffusion-bonded surface foils indicated that surface flaws typically account for a 20% decrease in failure strength. Compression creep tests at 650 and 700 °C indicated an improvement in creep strength over unreinforced IC-221.
DIET SELECTION AND RESOURCE USE BY FLYING FOXES (GENUS PTEROPUS)

Flying foxes of the genus Pteropus (Pteropodidae: Chiroptera) play important roles as pollinators and seed dispersers in oceanic-island forest communities. This research examined general theories of diet breadth, diet selection, and the evolution of feeding strategies in bats in light of information from members of the genus Pteropus that inhabit oceanic islands. The feeding ecology of two species of flying fox, Pteropus samoensis and Pteropus tonganus on the Samoan archipelago, was examined in detail by direct observation and by examining feeding refuse. P. samoensis and P. tonganus fed on over 78 plant species from 39 families throughout their range and on over 69 plant species in Samoa alone. Flying foxes interacted with 59% of the forest tree species in Amalau Valley for fruit or flower resources. Twenty-eight percent of the forest trees were commonly used, and 79% of forest canopy trees were used. Broad overlap in resource use was noted between P. samoensis and P. tonganus with over 22 shared plant species. Seasonal variation in fruit resource use was quantified with a preference index. Flying foxes ate a taxonomically nonrandom subset of fruit species and generally preferred primary forest fruits to those in the secondary forest. Six plant families (Sapotaceae, Mrytaceae, Moraceae, Combretaceae, Fabaceae, and Sapindaceae) were particularly important to flying foxes in Samoa. However, a set of core plant taxa does not exist for Pteropus spp. in Samoa. Differences in the evolution of feeding strategies between mainland fruit-eating chiroptera and island species likely reflect differences in the spatio-temporal availability of resources in the two systems.
Line-of-sight jitter of the Hubble Space Telescope

We report on the results of a dedicated on-orbit test which we have performed to measure the line-of-sight jitter of the Hubble Space Telescope. The test, which made use of one of the science instruments on board the spacecraft, had a very high sensitivity (a fraction of a milliarcsecond) and covered all frequencies up to 500 Hz. As was previously known from gyroscope data analysis, the bulk of the line-of-sight jitter occurs at frequencies lower than 5 Hz and is caused by motion of the spacecraft body reacting against the oscillation of its appendages. However, the test indicates that there are also minor contributions by various modes of the telescope structure in the 15 - 30 Hz range and the vibration of the primary mirror at 61 Hz when it is excited by thermally induced shocks or the running of the tape recorder. There are also traces of a component around 300 Hz induced by the tape recorder.
Silhouette photography of oceanic zooplankton

No adequate method has been available to characterise a sample of Zooplankton quickly and accurately. As Mullen noted1, although relatively rapid, measures of standing crop such as displacement volume, dry weight, carbon content and electronic size spectra do not distinguish clearly between animals and plant or detrital material, much less between herbivores and carnivores. Direct microscopic enumeration has remained the only approach giving information detailed enough for many ecological studies. Unfortunately, this method is time-consuming, it cannot be undertaken routinely at sea, and it is feasible only after chemical agents have been added to ‘fix’ and then ‘preserve’ the sample. With time, plankton samples always deteriorate in preservatives, although the degree of this effect varies with species. We report here that a little-known photographic technique—high-speed silhouette photography2,3—can be used to analyse live Zooplankton samples at sea.
An antagonistic effect with antioxidants for unsaturated fats

α-and γ-tocopherol act as pro-oxidants with marine oils containing the antioxidant EMQ. The term “antagonism” is suggested for such phenomena. Antagonism was also demonstrable in purified unsaturated fatty ester acids and triglycerides. Nitrogenous inhibitors (EMQ, DPPD, ADA) are more affected by added tocopherols than are the phenolic antioxidants examined (BHT, BHA, PG, NDGA). Phenolic antioxidants other than tocopherols do not show marked antagonism with EMQ.
Studies on a temperature-sensitive step essential to herpesvirus DNA replication

Abstract The nature of a previously described ( Stevens, 1966 ) heat-sensitive step essential to the replication of infectious bovine rhinotracheitis virus deoxyribonucleic acid has been investigated. By temperature “shift down” experiments, the step was found to occur 1 hour after infection. In addition, the virus was shown to induce increased activity of a unique DNA polymerase at both 37° and 42°. These results, when coupled with previous data, suggest that the heat-sensitive step is concerned with an essential change either in the intracellular location or in the physical state of the infecting DNA molecule.
C-terminal angiogenin peptides inhibit the biological and enzymatic activities of angiogenin.

Abstract Synthetic peptides corresponding to the C-terminal region of angiogenin (Ang) inhibit the enzymatic and biological activities of the molecule while peptides from the N-terminal region do not affect either activity. The peptide Ang(108–121) transiently abolishes the inhibition of cell-free protein synthesis caused by angiogenin coincidentally with its cleavage of reticulocyte RNA. Several C-terminal peptides also inhibit nuclease activity of angiogenin when tRNA is the substrate. Furthermore, peptide Ang(108–123) significantly decreases neovascularization elicited by angiogenin in the chick chorioallantoic membrane assay.
Application of the Fast Fourier Transform Algorithm to On-Line Reactor Diagnosis

The FFT computing algorithm, when implemented on a modern digital process computer, provides nearly realtime power spectrum analysis of noise signals. Programmable selection of frequency range, filter center frequencies, and bandwidths makes its use attractive for increasing the safety and availability of complex and expensive reactor systems through on-line monitoring of fluctuations in neutron or gamma flux, system pressure, or mechanical vibration.
Subharmonic motion of particles in a vibrating tube

We study the motion of strongly inelastic particles in a narrow vibrating tube using molecular-dynamics simulation. At low frequency of the vibration, we observe qualitative changes of the motion as the depth of the pile increases. The center of mass of the particle cloud can be described by a superposition of modes of different frequencies. For certain values of the depth, a single mode dominates. The frequency of the dominant mode is 1/2, 1/3, or 1/1 of the vibration. We suggest that the behavior can be understood in terms of a new time scale {tau}, reflecting the recompaction time for a finite-depth pile. {copyright} {ital 1998} {ital The American Physical Society}
Who Really Benefits From Nephron-sparing Surgery?

Objective To analyze the influence of preoperative renal function on postoperative renal outcomes after radical nephrectomy (RN) and nephron-sparing surgery (NSS) for malignancy in patients stratified according to preoperative chronic kidney disease (CKD) stage and surgical extent (NSS vs RN). Patients and Methods Retrospective review of patients undergoing renal surgery for localized renal masses stratified by surgical extent and preoperative CKD stage based on glomerular filtration rate (GFR) level: stage I (>90 mL/min/1.73 m 2 ), stage II (60-89 mL/min/1.73 m 2 ), and stage III (30-59 mL/min/1.73 m 2 ). Survival analysis for significant renal impairment was based on freedom from the development of new-onset GFR 2 . Results A total of 1306 patients were included in the analysis with preoperative CKD stage I (27.9%), II (52.1%), and III (20.1%); 41.3% and 58.7% underwent NSS and RN, respectively. NSS was associated with a lower annual rate of GFR decline in preoperative CKD stage-I ( P = .028) and stage-II patients ( P = .018), but not in CKD stage-III patients ( P = .753). Overall, 5.0% and 15.0% developed new-onset GFR 2 and 2 , respectively. There was no difference in the probability of developing significant renal impairment between NSS and RN in CKD stage-I or -III patients, whereas only in CKD stage-II patients was the surgical extent independently associated with development of significant renal impairment (RN: odds ratio, 9.0; P = .042 for GFR 2 and odds ratio, 2.3; P = .003 for GFR 2 ). Conclusion Compared with RN, NSS is associated with a lower rate of GFR decline for preoperative CKD stage-I and -II patients, but only CKD stage-II patients demonstrated a decreased risk of developing significant renal impairment.
Memory and suggestibility in older adults: live event participation and repeated interview

One hundred and thirteen young (mean age: 20.2 years) and older adults (mean age: 76.4 years) participated in an event that entailed various relaxation techniques, such as a body massage and aromatherapy. On two separate occasions several weeks following participation, half of each group was given misleading information about certain aspects of the event, including suggestions that they had been massaged on parts of their body which had not been touched. Results showed that older adults were disproportionately influenced by the presentation of erroneous suggestions. These findings add to the small but growing body of knowledge about the vulnerability of older eyewitnesses. Copyright © 2004 John Wiley & Sons, Ltd.
Clinical Pharmacokinetics of Paclitaxel

Paclitaxel is a new anticancer agent showing significant promise as therapy for solid tumours and leukaemia, given alone or in combination with other chemotherapeutic agents. Paclitaxel concentrations in biological specimens can be measured using high performance liquid chromatography, or more recently by immunoassay.
Spiral Sling Salvage Anti-Incontinence Surgery for Women With Refractory Stress Urinary Incontinence: Surgical Outcome and Satisfaction Determined by Patient-Driven Questionnaires

PURPOSE Female patients with refractory stress urinary incontinence (SUI) are a unique surgical challenge. They undergo multiple surgical procedures and eventually are left with urethral closure and continent diversion as their final option. We previously presented our initial experience of a technique that provides circumferential coaptation of the urethra in patients with severe urethral incompetence due to neurologic injuries or congenital anomalies. This study expands on that experience and reports on the clinical and quality of life of patients after spiral sling placement in a defined population of patients with refractory SUI. METHODS We prospectively evaluated 46 patients with refractory SUI who had undergone spiral sling placement. The surgical outcome was determined by clinical history and physical examination and, primarily, by patient self-assessment and included validated symptom, bother, and quality-of-life questionnaires. RESULTS Their mean age was 62 years. The mean follow-up was 15 months. At presentation, the patients had undergone a mean of 2.8 incontinence procedures and wore a mean of 5.5 pads daily. The mean pad use decreased to 1.3 pads daily (P <.05). Preoperatively, the mean severity and bother score from the SUI symptoms was 3.0 and 2.9, respectively (0, none; 3, severe). Postoperatively, these numbers decreased to 1.0 and 0.8 (P <.05). The mean overall improvement in symptoms was 82%. No perioperative complications developed. The procedure failed in 1 patient, who underwent urethral closure with urinary diversion. Two patients underwent repeat proximal spiral sling procedure. CONCLUSIONS The spiral sling is an effective salvage transvaginal procedure that can be considered for female patients with refractory SUI.
Quantitative analysis of cerebral cortical atrophy and correlation with clinical severity in unilateral Sturge-Weber syndrome

Sturge-Weber syndrome is a neurocutaneous disorder with vascular malformations of the skin, brain, and eye. The objective of this study was to determine whether cortical atrophy in patients with Sturge-Weber syndrome correlates with clinical severity. Eighteen subjects (age 4 months-35 years) with unilateral Sturge-Weber syndrome received a neurologic examination and submitted previous magnetic resonance imaging (MRI) films. A blinded investigator assigned clinical severity scores based on seizures, hemiparesis, visual field cut, and cognitive impairments. Computer-aided analysis of MRIs produced laterality scores for cortical volume asymmetry. A significant relationship existed between clinical severity and laterality scores (Spearman's rho = -0.804; P < .001). Laterality scores also correlated well with hemiparesis subscores and weakly with cognitive impairment subscores (Kendall's tau b; P < .05). Using this simple, computer-aided analysis, cortical volume asymmetry correlated with clinical status. This method offers the advantages of relative simplicity, objectivity, and wide applicability to films from outside institutions, as would be encountered in clinical practice.
Estimation and Accuracy after Model Selection.

Classical statistical theory ignores model selection in assessing estimation accuracy. Here we consider bootstrap methods for computing standard errors and confidence intervals that take model selection into account. The methodology involves bagging, also known as bootstrap smoothing, to tame the erratic discontinuities of selection-based estimators. A useful new formula for the accuracy of bagging then provides standard errors for the smoothed estimators. Two examples, nonparametric and parametric, are carried through in detail: a regression model where the choice of degree (linear, quadratic, cubic, …) is determined by the Cp criterion and a Lasso-based estimation problem.
Dynamic mechanical studies of the glass transition temperature of photopolymerized multifunctional acrylates

The glass transition temperatures of the highly crosslinked networks formed from photopolymerizing-the multifunctional monomers trimethylol propane triacrylate (TrMP TrA), pentaerythritol tetraacrylate (PETeA), and dipentaerythritol monohydroxy pentaacrylate (DPEMHP eA) were determined using a dynamic viscoelastometer. All glass transition temperatures, Tg, were in excess of 150°C indicating the highly crosslinked structure of the resulting networks. The curves of the damping factor as a function of temperature were broadened peaks spanning up to 100°C due to the extreme heterogeneity of these structures. Evidence of trapped radicals was also observed as cured samples subjected to a thermal pretreatment had higher Tg than those without the thermal pretreatment.
Thermal desorption methods for porosity characterization of carbons and chars

Abstract A novel approach is presented and explored for porosity characterization and the study of porosity development in carbons and chars during activation processes. This approach involves the interpretation of post-activation temperature programmed desorption (TPD) spectra. The procedure involves first forming oxygen complexes on a carbon surface by oxygen gasification. Subsequently, the sample temperature is raised in a low-pressure inert carrier gas (helium) at a programmed heating rate, during which the rates of evolution of CO and CO2 are measured. A comparison of gas evolution results and surface areas determined from nitrogen adsorption isotherms using the αs-plot method, show that there exist strong correlations between the nature of the resultant porosity and its development, and post-reaction desorption features of oxygen surface complexes formed during the activation process. It is demonstrated that the surface area of the larger pores and the total CO2 evolved upon TPD are correlated. It is concluded that the CO-evolving complexes are formed over the entire surface area of the chars during activation, but that the surface area in the larger porosity is primarily responsible for the formation of CO2-evolving surface complexes. The relationship between micropore surface area and the CO evolution ‘corrected’ for the expected contribution from carboxylic acid anhydride surface complexes in the larger porosity, indicates that these latter types of complexes may be responsible for much of the CO2 evolution under conditions when oxygen is the activating agent.
A cosmological redshift-distance square law?

This paper directly examines the claims of Segal (1976) that the (m,z) Hubble diagram is fitted best by a square law z = Kr-squared rather than by the traditional Hubble law z = Hr in the low-redshift range, z no more than about 0.01, corresponding to galaxies brighter than 14th mag. Segal attempts to fit a distance relation to the (m,z) scatter diagram in which each individual galaxy is plotted. The exact relation between the mean redshift for all galaxies in a small magnitude interval and the apparent magnitude is calculated. This relation is independent of luminosity function and peculiar velocity distribution about the general expansion, and is not affected by sample incompleteness as a function of apparent magnitude or the clustering of galaxies in the sample. Segal's method is affected by all of these and requires a highly sophisticated statistical analysis to deal with the non-Gaussian pointwise scatter. The present analysis favors the Hubble law and conclusively rules out the square law for the small redshift region.
Space Station Operations Would Extend Until at Least 2024 Under Obama Plan

An 8 January decision by the White House to propose an extension of the International Space Station's (ISS) operation until at least 2024 would allow for increased research on board the floating laboratory, a longer planning horizon for commercial activities, and a continuation of international cooperation in space, administration officials said. The proposal, which has received initial support from some key members of Congress, would be the second extension for ISS under the Obama administration and would accommodate increased research related to long-duration human space flight, Earth science, and other areas. ISS, which in the United States is authorized under the NASA Authorization Act of 2010, was last extended in 2010 and costs about $3 billion annually to operate.
Engineering triterpene metabolism in tobacco

Terpenes comprise a distinct class of natural products that serve a diverse range of physiological functions, provide for interactions between plants and their environment and represent a resource for many kinds of practical applications. To better appreciate the importance of terpenes to overall growth and development, and to create a production capacity for specific terpenes of industrial interest, we have pioneered the development of strategies for diverting carbon flow from the native terpene biosynthetic pathways operating in the cytosol and plastid compartments of tobacco for the generation of specific classes of terpenes. In the current work, we demonstrate how difficult it is to divert the 5-carbon intermediates DMAPP and IPP from the mevalonate pathway operating in the cytoplasm for triterpene biosynthesis, yet diversion of the same intermediates from the methylerythritol phosphate pathway operating in the plastid compartment leads to the accumulation of very high levels of the triterpene squalene. This was assessed by the co-expression of an avian farnesyl diphosphate synthase and yeast squalene synthase genes targeting metabolism in the cytoplasm or chloroplast. We also evaluated the possibility of directing this metabolism to the secretory trichomes of tobacco by comparing the effects of trichome-specific gene promoters to strong, constitutive viral promoters. Surprisingly, when transgene expression was directed to trichomes, high-level squalene accumulation was observed, but overall plant growth and physiology were reduced up to 80 % of the non-transgenic controls. Our results support the notion that the biosynthesis of a desired terpene can be dramatically improved by directing that metabolism to a non-native cellular compartment, thus avoiding regulatory mechanisms that might attenuate carbon flux within an engineered pathway.
An agreement approach to predict severe angiographic coronary artery disease with clinical and exercise test data.

Abstract Objective To demonstrate that an agreement approach to applying equations on the basis of clinical and exercise test variables is an accurate, self-calibrating, and cost-efficient method for predicting severe coronary artery disease in clinical populations. Design Retrospective analysis of consecutive patients with complete data from exercise testing and coronary angiography referred for evaluation of possible coronary artery disease. After developing an equation in a training set, this equation and two other equations developed by other investigators were validated in a test set. The study was performed at two university-affiliated Veteran's Affairs medical centers. Patients 1080 consecutive men studied between 1985 and 1995 who had coronary angiography within 3 months of the treadmill test. The population was randomly divided into a training set of 701 patients and a test set of 379 patients. Patients with previous coronary artery bypass surgery, valvular heart disease, marked degrees of resting ST depression, and left bundle branch block were excluded. Measurements Recording of clinical and exercise test data along with visual interpretation of the electrocardiogram recordings on standardized forms and abstraction of visually interpreted angiographic data from clinical catheterization reports. Results Simple clinical and exercise test variables improved the standard application of exercise-induced ST criteria for predicting severe coronary artery disease. By setting probability thresholds for severe disease of 40% for the three prediction equations, the agreement approach divided the test set into three groups: low risk (patients with all three equations predicting 39% probability) for severe coronary artery disease. Because the patients in the no agreement group would be sent for further testing and would eventually be correctly classified, the sensitivity of the agreement approach was 89% and the specificity was 96%. The agreement approach appeared to be unaffected by disease prevalence, missing data, variable definitions, or even angiographic criteria. Conclusions Requiring diagnosis of severe coronary disease to be dependent on agreement between these three equations has made them likely to function in all clinical populations. The agreement approach should be an efficient method for the evaluation of populations with varying prevalence of coronary artery disease, limiting the use of more expensive noninvasive and invasive testing to patients with a higher probability of left main or triple-vessel coronary artery disease. This approach provides a strategy that can be applied by inputting the results of basic clinical assessment into a programmable calculator or a computer to assist the practitioner in deciding when further evaluation is appropriate, thus assuring patients access to subspecialty care. (Am Heart J 1997;134:672-9.)
Rado Numbers for the Equation Σ i=1 m-1 x i +c=x m , for Negative Values of c

For every integer m>=3 and every integer c, let r(m,c) be the least integer, if it exists, such that for every 2-coloring of the set {1,2,...,r(m,c)} there exists a monochromatic solution to the [email protected]?i=1m-1x"i+c=x"m.The values of r(m,c) were previously known for all values of m and all nonnegative values of c. In this paper, exact values of r(m,c) are found for all values of m and all values of c such that -m+2
Synthesis of Processor Allocator for Torus-Based Chip MultiProcessors

Chip MultiProcessor (CMP) architectures are dominant trend in parallel processing systems. With the number of on-chip processors rising to the hundreds, allocation and management of the processors are also important factor to achieve high efficiency of CMPs. In this paper, the authors study a Processor Allocator (PA) for CMP based on torus Network-on-Chip. The best, IFF and IAS algorithms for mesh-based CMP are presented and their torus extension is proposed. The synthesis of both IFF and IAS allocation techniques for mesh and torus topologies is performed and its results are analyzed. The presented outcomes reveal the significant advantage of the PA driven by bit map algorithms. The mesh-based PA driven by the IFF scheme outperformed the other techniques by good frequency characteristic and low logic utilization. For the torus-based PA only the IFF technique with torus extension remains the reasonable solution, however its performance characteristic is weaker in comparison to the mesh counterpart.
Trace synthesis in cued recall

Abstract Several memory models propose that recall may combine traces of different memories. Such models predict blend errors during cued recall. To examine memory blending during recall, four experiments were performed. In each experiment, subjects rated the plausibility of several sentences, many of which shared words with one other sentence. Later, they were asked to recall words from a single sentence to complete partial-sentence cues. When the cue matched two study sentences, subjects made blend errors, recalling one word from each study sentence more frequently than in a control condition. Blend errors were relatively infrequent, however, occurring on about 5% of opportunities. A good account of the results was provided by a stochastic interactive activation model that causes blend errors by synthesizing traces during retrieval.
Hormonal contraception and trophoblastic sequelae after hydatidiform mole (A Gynecologic Oncology Group study)

A prospective randomized study was undertaken to determine whether the administration of oral contraceptives after the evacuation of a hydatidiform mole affects the human chorionic gonadotropin serum level in a way that leads to an increased frequency in the diagnosis of postmolar trophoblastic disease. Between 1981 and 1988, 266 patients were randomly assigned to either oral contraceptives or barrier contraception after evacuation of a hydatidiform mole. Patients were followed up until serum levels of human chorionic gonadotropin were normal or until specific criteria for the diagnosis of postmolar trophoblastic disease were met. Twenty-three percent of patients receiving oral contraceptives had postmolar trophoblastic disease, whereas those using a barrier method had a rate of 33%. The median time to spontaneous regression in the oral contraceptives group was 9 weeks, whereas the median time to regression in the barrier group was 10 weeks. Twice as many patients in the barrier group became pregnant in the immediate follow-up period. We conclude that oral contraceptives are the preferred method of contraception after evacuation of a hydatidiform mole.
Automatic preparation of protein crystals using laboratory robotics and automated visual inspection

Abstract A significant concern in the field of protein crystallography remains the routine preparation of single crystals suitable for x-ray diffraction studies. Crystallization techniques developed within the last three decades typically require accurate manipulation of microliter quantities of protein, buffer, and precipitating solutions. The accuracy and reproducibility necessary for such processes, together with the repetitiveness of the tasks, make several of the crystallization methods particularly appropriate for automation techniques. We describe here our efforts to automate the preparation of protein crystals by the sandwiched drop method using commercially available laboratory robotics equipment. The system incorporates a video monitoring station which permits automated inspection of individual crystallization droplets. Results obtained from the automatic monitoring of crystallization experiments will be utilized to redesign and prepare new experiments which will then be carried out by the robotics system, thereby allowing a more fully automated system for crystallization.
An empirical investigation of the advertising spending decisions of a multiproduct retailer

Abstract In a multiproduct retailing context, an approach for testing marketing mix variables is presented that should be of interest to retailers and researchers alike. Traditional model building for decision evaluation purposes suffers from a serious drawback in that the underlying model is assumed to be known. The present approach incorporates the search for the “true” model as an intrinsic part of the method. Based on up to date modeling perspectives, the approach can be divided into three steps: (1)the use of multiple time series analysis to assist in model specification; (2) the choice of functional form, model estimation and testing; and (3) the use of statistical and simulation methods to test decision making hypotheses. The approach is applied to three years of a western wear retailer's weekly sales and advertising data; multiple time series analysis is used to specify a simultaneous equation model that captures demand interdependences. After subjecting the model to several stability tests, it is then used as a basis for testing several interesting hypotheses concerning the retailer 's advertising decision making behavior. The key insight for multiproduct retailers is that advertising budget allocation decisions across products and media are probably more important than decisions affecting the level of the total budget since the former have a greater impact on profit contribution.
The electric motor, the telegraph, and Joseph Henry's theory of technological progress

Joseph Henry (1797-1878), America's foremost electrical physicist of the early nineteenth century, stood at the center of the developing science and technology of the newly discovered electric current. The electromagnetic telegraph and the battery-powered motor were two leading technological efforts of the period. Although Henry chose not to engage in the actual inventive process, he closely followed the development of both devices. While he fully supported the work on the telegraph, especially S.F.B. Morse's experiments, he stood opposed to the battery-powered motor on the grounds of impracticality. He stated these views forcefully to the numorous inventors who sought his expert advice on electricity. This paper explores the reasons for Henry's contrasting opinions of the telegraph and the motor. Underlying these opinions was a set of assumptions about the progress of technology and its proper relations to scientific knowledge and the current needs of society.
Ultrafast infrared spectroscopy probes hydrogen-bonding dynamics in liquid water

Time-resolved infrared spectroscopy has the potential to provide unprecedented information about molecular dynamics in liquids. In the case of water, one of the most exciting techniques being developed is transient hole-burning. From experiments on dilute HOD in D2O one can obtain the transition frequency time-correlation function for the OH stretch, finding that it decays on a time scale of between 0.5 and 1 ps. In this report we provide a molecular-level interpretation of this spectral diffusion in terms of the dynamics of forming and breaking hydrogen bonds.
Characterization of Aquifex aeolicus ribonuclease III and the reactivity epitopes of its pre-ribosomal RNA substrates

Ribonuclease III cleaves double-stranded (ds) structures in bacterial RNAs and participates in diverse RNA maturation and decay pathways. Essential insight on the RNase III mechanism of dsRNA cleavage has been provided by crystallographic studies of the enzyme from the hyperthermophilic bacterium, Aquifex aeolicus. However, the biochemical properties of A. aeolicus (Aa)-RNase III and the reactivity epitopes of its substrates are not known. The catalytic activity of purified recombinant Aa-RNase III exhibits a temperature optimum of ∼70–85°C, with either Mg2+ or Mn2+ supporting efficient catalysis. Small hairpins based on the stem structures associated with the Aquifex 16S and 23S rRNA precursors are cleaved at sites that are consistent with production of the immediate precursors to the mature rRNAs. Substrate reactivity is independent of the distal box sequence, but is strongly dependent on the proximal box sequence. Structural studies have shown that a conserved glutamine (Q157) in the Aa-RNase III dsRNA-binding domain (dsRBD) directly interacts with a proximal box base pair. Aa-RNase III cleavage of the pre-16S substrate is blocked by the Q157A mutation, which reflects a loss of substrate binding affinity. Thus, a highly conserved dsRBD-substrate interaction plays an important role in substrate recognition by bacterial RNase III.
Tandem columns and mixed-bed columns in high-performance liquid chromatography of proteins

By using a cation- and an anion-exchange column in series, mixtures of acidic and basic proteins were separated in a single chromatographic run with increasing salt gradient at pH 7.0. The serial order of the columns was found to affect the chromatographic results, and the effect was attributed to alteration of the salt gradient profile upon traversing the first ion-exchange column. Single columns, packed with a binary mixture of a cation and an anion exchanger gave similar chromatographic results as the tandem columns and thus offered an alternative approach to the separation of both acidic and basic proteins in a single chromatographic run. A ternary mixed phase was obtained by adding a mildly hydrophobic stationary phase to the mixture of the two ion exchangers. This column could be used with increasing salt gradient as a cation exchanger for the separation of basic proteins, or as an anion exchanger for the separation of acidic proteins. Furthermore, it could be used as a “bipolar” electrostatic-interaction column with increasing salt gradient and as a hydrophobic-interaction column with decreasing salt gradient for the separation of both types of proteins in a single chromatographic run. The constituent stationary phases used in the mixed-bed columns were prepared from the same silica support, i.e., they had the same particle and pore dimensions, density, and pore volume. Besides their obvious advantages in analytical applications, appropriate mixed stationary phases, all having retentive properties for the components to be separated, are expected to be useful also in preparative chromatography to “tailor” column selectivity for a given separation problem without loss of separating capacity.
Late Pleistocene human population bottlenecks, volcanic winter, and differentiation of modern humans☆

The “Weak Garden of Eden” model for the origin and dispersal of modern humans (Harpendinget al., 1993) posits that modern humans spread into separate regions from a restricted source, around 100 ka (thousand years ago), then passed through population bottlenecks. Around 50 ka, dramatic growth occurred within dispersed populations that were genetically isolated from each other. Population growth began earliest in Africa and later in Eurasia and is hypothesized to have been caused by the invention and spread of a more efficient Later Stone Age/Upper Paleolithic technology, which developed in equatorial Africa. Climatic and geological evidence suggest an alternative hypothesis for Late Pleistocene population bottlenecks and releases. The last glacial period was preceded by one thousand years of the coldest temperatures of the Later Pleistocene (∼71–70 ka), apparently caused by the eruption of Toba, Sumatra. Toba was the largest known explosive eruption of the Quaternary. Toba's volcanic winter could have decimated most modern human populations, especially outside of isolated tropical refugia. Release from the bottleneck could have occurred either at the end of this hypercold phase, or 10,000 years later, at the transition from cold oxygen isotope stage 4 to warmer stage 3. The largest populations surviving through the bottleneck should have been found in the largest tropical refugia, and thus in equatorial Africa. High genetic diversity in modern Africans may thus reflect a less severe bottleneck rather than earlier population growth. Volcanic winter may have reduced populations to levels low enough for founder effects, genetic drift and local adaptations to produce rapid population differentiation. If Toba caused the bottlenecks, then modern human races may have differentiated abruptly, only 70 thousand years ago.
Disruption of Staphylococcus epidermidis biofilm formation using a targeted cationic peptide.

This study reports the use of a targeted cationic peptide with the ability to disrupt Staphylococcus epidermidis biofilm formation. Complications due to nosocomial infections of implanted medical devices pose a significant health risk to patients, with Staphylococcus epidermidis often implicated in the case of blood-contacting biomaterials. S. epidermidis virulence relies mainly on its ability to form a biofilm, the main component of which is polysaccharide intercellular adhesin (PIA). We utilized the synthetic β6-20 peptide, known to specifically bind S. epidermidis, in order to deliver a cationic polylysine peptide (G3K6) to the bacterial surface and disrupt the charge–charge interactions needed for PIA retention and biofilm stability. The effects of the β6-20-G3K6 peptide on biofilm formation were assessed using optical density, fluorescently labeled wheat germ agglutinin, nucleic acid stain (SYTO 9), and a metabolic assay (XTT, 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide inner salt). Biofilms formed in the presence of β6-20-G3K6 peptide (100 μM) resulted in a 37.9% reduction in PIA content and a 17.5% reduction of adherent bacteria relative to biofilms grown in the absence of peptide. These studies demonstrate the targeting ability of the β6-20 peptide towards biomaterial-adherent S.epidermidis, and highlight the potential for disrupting the early stages of biofilm formation. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A:, 2012.
Path-integral Monte Carlo simulation of helium at negative pressures

Path-integral Monte Carlo simulations of liquid helium at negative pressure have been carried out for a temperature range from the critical temperature to below the superfluid transition. We have calculated the temperature dependence of the spinodal line as well as the pressure dependence of the isothermal sound velocity in the region of the spinodal. We discuss the slope of the superfluid transition line and the shape of the dispersion curve at negative pressures.
How do new BSN nurses perceive their nursing education

Objective: The goal was to determine if new bachelor’s of science in nursing (BSN) nurses perceived their education to be relevant for the current demands of the profession. Methods: The design was nonexperimental, descriptive survey research. Data were gathered using a researcher-designed mailed survey. Addresses for survey participants, RNs who had graduated with a BSN within 2 years prior to June 2012, were obtained from the North Carolina State Board of Nursing. Results: This study found that new gradu- ates in the sample perceived their academic preparation to be adequate for transitioning into professional practice; however, new graduates wish they’d had more opportunities to practice clinical skills while in nursing school. Respondents also perceived that some health assessment content included in nursing programs may not typically be useful in entry-level nursing practice. Conclusions: Because a large percentage of the sample perceived they’d had inadequate clinical practice time, new nurses might not feel completely com- petent with practice-related skills. Employers should take this into consider- ation when structuring orientation programs. Additionally, the curricula planners for BSN programs might creatively and strategically consider ways to increase or improve the clinical practice opportunities for nursing students.
Constitutions, Corporations, and Corruption: American States and Constitutional Change, 1842 to 1852

Between 1842 and 1852, eleven states adopted new constitutions, simultaneously creating procedures for issuing government debt and for chartering corporations through general incorporation acts. Why simultaneously? Voters wanted geographically specific infrastructure investments but opposed geographically widespread taxation. States resolved the dilemma by developing several innovative public finance schemes. One, "taxless finance," used borrowed funds and special corporate privileges without raising current taxes. Another scheme, "benefit taxation," coordinated the incidence of taxes with the geographic benefits of investments through the property tax. After the fiscal crisis of the early 1840s, states changed their constitutions to eliminate taxless finance in the future. Between 1790 and 1860 the United States population moved west over the Appalachians and across the Gulf plains, creating new states as they went. The states, with some federal assistance, constructed a system of finance and transportation to tie the nation together. The states also developed a set of economic institutions that allowed free entry into the corporate form, limited the ability of governments to incur unfunded debts, encouraged generally responsible public finance, and demonstrated that a democratic republic could deliver on a commitment to secure private property rights and the rule of law. These accomplishments are celebrated parts of American economic history. Were they related? Specifically, did state government efforts to provide the physical and commercial infrastructure lead to changes in, or follow from, existing economic and political institutions?
Reducing the numerical effort of finite-temperature density matrix renormalization group calculations

Finite-temperature transport properties of one-dimensional systems can be studied using the time dependent density matrix renormalization group via the introduction of auxiliary degrees of freedom which purify the thermal statistical operator. We demonstrate how the numerical effort of such calculations is reduced when the physical time evolution is augmented by an additional time evolution within the auxiliary Hilbert space. Specifically, we explore a variety of integrable and non-integrable, gapless and gapped models at temperatures ranging from T = ∞ down to T/bandwidth = 0.05 and study both (i) linear response where (heat and charge) transport coefficients are determined by the current–current correlation function and (ii) non-equilibrium driven by arbitrary large temperature gradients. The modified density matrix renormalization algorithm removes an 'artificial' build-up of entanglement between the auxiliary and physical degrees of freedom. Thus, longer time scales can be reached.
Integrin Dependence of Calu-1 Cell Motility on Endothelial Extracellular Matrix Proteins

We recently showed that the motility of the malignant Calu-1 human epidermoid lung carcinoma cells correlates to their expression levels of α2, α3, α6, and β1 integrin subunits. To determine a causative relationship underlying this correlation, here we measured Calu-1 cell adhesion to and migration on laminin, collagen IV, human umbilical vein endothelial cell monolayers, and endothelial cell extracellular matrix in the presence of function-blocking antibodies against the suspect integrin subunits. Blocking individual α subunits did not affect adhesion to or motility on laminin, but when used in pair-wise combinations, monoclonal antibody treatments significantly decreased tumor cell motility on, without diminishing adhesion to, laminin and the other substrates. Blocking all three α subunits at once or the β1 subunit alone abolished migration on laminin; however, the latter treatment also abolished adhesion, whereas the former treatment did not. By contrast, blocking the β1 subunit significantly reduced motility on collagen IV, endothelial cell monolayers, and endothelial cell extracellular matrix, but always without affecting adhesion. These results suggest a separation of roles and mechanisms of different integrins in adhesion and motility.
Cellular enzymology: the steady-state kinetics of compartmentalized enzymes.

Attempts to apply traditional techniques of enzyme kinetic analysis(Lineweaver-Burk and Eadie-Hofstee plots) to enzymes compartmentalized by the membranes of cells, organelles, or vesicular membrane fragments will generally lead to incorrect estimates of the kinetic constants of the enzymes and incorrect conclusions about the mechanism of reaction. The error is the consequence of concentration differences, arising through the reaction process, between the solution outside the cell or organelle membrane and the solution in the interior where the reaction is taking place. The use of enzymological plots to interpret data from membrane transport studies, for example, may therefore be misleading. The specific form of the modifications to be expected in these plots for the most common types of reaction mechanisms is presented in the text in graphical form, with the algebraic expressions summarized in an appendix. The plots show curvatures which may be incorrectly interpreted as implying co-operative kinetics when, in fact, they are quite pedestrian. In some simple cases, there exist alternative ways of plotting the data which permit the correct evaluation of kinetic constants and distinction among mechanisms. The effect of cellular compartmentation on inhibition studies is also described.