cssi/SciSciGPT-SciSciNet huggingface dataset:
Regulation of the HscA ATPase Reaction Cycle by the Co-chaperone HscB and the Iron-Sulfur Cluster Assembly Protein IscU

The ATPase activity of HscA, a specialized hsp70 molecular chaperone from Escherichia coli, is regulated by the iron-sulfur cluster assembly protein IscU and the J-type co-chaperone HscB. IscU behaves as a substrate for HscA, and HscB enhances the binding of IscU to HscA. To better understand the mechanism by which HscB and IscU regulate HscA, we examined binding of HscB to the different conformational states of HscA and the effects of HscB and IscU on the kinetics of the individual steps of the HscA ATPase reaction cycle. Affinity sensor studies revealed that whereas IscU binds both ADP (R-state) and ATP (T-state) HscA complexes, HscB interacts only with an ATP-bound state. Studies of ATPase activity under single-turnover and rapid mixing conditions showed that both IscU and HscB interact with the low peptide affinity T-state of HscA (HscA++.ATP) and that both modestly accelerate (3-10-fold) the rate-determining steps in the HscA reaction cycle, k(hyd) and k(T-->R). When present together, IscU and HscB synergistically stimulate both k(hyd) (approximately = 500-fold) and k(T-->R) (approximately = 60-fold), leading to enhanced formation of the HscA.ADP-IscU complex (substrate capture). Following ADP/ATP exchange, IscU also stimulates k(R-->T) (approximately = 50-fold) and thereby accelerates the rate at which the low peptide affinity HscA++.ATP T-state is regenerated. Because HscA nucleotide exchange is fast, the overall rate of the chaperone cycle in vivo will be determined by the availability of the IscU-HscB substrate-co-chaperone complex.
Demonstration of bioaugmentation in a fluidized-bed process treating 1-naphthylamine

Abstract The feasibility of using a fluidized-bed reactor with bioaugmentation to treat low-strength wastewater or slightly contaminated groundwater was evaluated. Tap water spiked with 1.6 to 12.6 mg/L of 1-naphthylamine was treated in a fluidized-bed reactor with a hydraulic retention time of 6.2 to 13.3 h. With conventional operation, the reactor was unable to maintain consistent removal because of cell washout. Continuous removal efficiency was greater than 90% using bioaugmentation through periodic addition of acclimated cells from an off-line enricher-reactor. The concept demonstrated by this research presents an alternative for biological treatment of wastes (dilute wastewaters and contaminated groundwater) which are not normally considered good candidates for biological treatment.
Teamwork mentality in neurosurgical teams to improve patient safety.

eamwork is defined as “work done by several associates with each doing a part but all subordinating personal T prominence to the efficiency of the whole” (1). It is now universally recognized that a team that works effectively is the most powerful tool available to develop and grow their people and to optimize the activity to be completed. In the last few decades the culture of teamwork has become more and more significant in terms of the resulting socioeconomic impact. According to the American Society of Training and Development, companies that have been oriented toward team building have seen greatly increased productivity, quality, customer and employee satisfaction, and a greater ability to solve problems and disputes. Again, psychological studies have demonstrated that a team that works effectively allows each member to become smarter, more creative, and more sociable, and thus to contribute to the full development of an overall team personality. In effect, teamwork creates a form of distributed cognition that recognizes that we operate in systems both that are larger than isolated individuals and that take on a collective mind. This view extends our reach to encompass interactions between people, as well as interactions with resources in the environment. This is a well-described phenomenon in complex team settings such as flight crews (6, 10), operating rooms (ORs) and emergency rooms (5, 8), and ship navigation (9). To be effective in achieving its goals, a team should have the following characteristics:
Variation in rate of growth in the crayfish Orconectes virilis

ABSTRACT Mark-recapture data on individually marked adult Orconectes virilis living in a stream in southeastern Michigan were used to estimate growth rate and survivorship. Growth rates calculated for this population are markedly higher than those published for other populations of this species and are consistent with the exceptional size of these crayfish.
On Generating Knowledge in Service to Society.

In the US debate over science‐based educational research, experimentation is again coming to the fore as ideal for establishing an evidence base of what works in educational interventions thus contributing to the climate of accountability in educational research and practice. Mixed methods research is being positioned in this discussion as a reasonable alternative, a way of making it possible for both experimentalists and non‐experimentalists to join forces in the quest for accountability. This paper argues that mixed methods research is hardly something new; moreover, it is an epistemological response to what is basically a moral–political problem.
Infant Brain Extraction in T1-Weighted MR Images Using BET and Refinement Using LCDG and MGRF Models

In this paper, we propose a novel framework for the automated extraction of the brain from T1-weighted MR images. The proposed approach is primarily based on the integration of a stochastic model [a two-level Markov–Gibbs random field (MGRF)] that serves to learn the visual appearance of the brain texture, and a geometric model (the brain isosurfaces) that preserves the brain geometry during the extraction process. The proposed framework consists of three main steps: 1) Following bias correction of the brain, a new three-dimensional (3-D) MGRF having a 26-pairwise interaction model is applied to enhance the homogeneity of MR images and preserve the 3-D edges between different brain tissues. 2) The nonbrain tissue found in the MR images is initially removed using the brain extraction tool (BET), and then the brain is parceled to nested isosurfaces using a fast marching level set method. 3) Finally, a classification step is applied in order to accurately remove the remaining parts of the skull without distorting the brain geometry. The classification of each voxel found on the isosurfaces is made based on the first- and second-order visual appearance features. The first-order visual appearance is estimated using a linear combination of discrete Gaussians (LCDG) to model the intensity distribution of the brain signals. The second-order visual appearance is constructed using an MGRF model with analytically estimated parameters. The fusion of the LCDG and MGRF, along with their analytical estimation, allows the approach to be fast and accurate for use in clinical applications. The proposed approach was tested on in vivo data using 300 infant 3-D MR brain scans, which were qualitatively validated by an MR expert. In addition, it was quantitatively validated using 30 datasets based on three metrics: the Dice coefficient, the 95% modified Hausdorff distance, and absolute brain volume difference. Results showed the capability of the proposed approach, outperforming four widely used BETs: BET, BET2, brain surface extractor, and infant brain extraction and analysis toolbox. Experiments conducted also proved that the proposed framework can be generalized to adult brain extraction as well.
Strong resistance of citrate anions on metal nanoparticles to desorption under thiol functionalization

Thiols are widely utilized to functionalize metal nanoparticles, including ubiquitous citrate-stabilized gold nanoparticles (AuNPs), for fundamental studies and biomedical applications. For more than two decades, citrate-to-thiol ligand exchange has been used to introduce functionality to AuNPs in the 5-100 nm size regime. Contrary to conventional assumptions about the completion of ligand exchange processes and formation of a uniform self-assembled monolayer (SAM) on the NP surface, coadsorption of thiols with preadsorbed citrates as a mixed layer on AuNPs is demonstrated. Hydrogen bonding between carboxyl moieties primarily is attributed to the strong adsorption of citrate, leading to the formation of a stabilized network that is challenging to displace. In these studies, adsorbed citrates, probed by Fourier transform infrared and X-ray photoelectron spectroscopy (XPS) analyses, remain on the surface following thiol addition to the AuNPs, whereas acetoacetate anions are desorbed. XPS quantitative analysis indicates that the surface density of alkyl and aryl thiolates for AuNPs with an average diameter of ∼40 nm is 50-65% of the value of a close-packed SAM on Au(111). We present a detailed citrate/thiolate coadsorption model that describes this final mixed surface composition. Intermolecular interactions between weakly coordinated oxyanions, such as polyprotic carboxylic acids, can lead to enhanced stability of the metal-ligand interactions, and this needs to be considered in the surface modification of metal nanoparticles by thiols or other anchor groups.
Novel High Efficiency Polarizing Backlighting System with a Polarizing Beam Splitter

A novel high efficiency polarizing backlight system is proposed that is based on novel broadband and wide-angle polarizing beam-splitters (PBS). The principle of the backlight system, the performance of the two PBSs and the computer-simulated results will be presented.
Interactions of forward and simultaneous masking in intensity discrimination.

Intensity coding mechanisms are explored in a paradigm involving both forward and simultaneous masking. For intensity discrimination of 1000-Hz pure tone in quiet, a near-miss to Weber’s law is observed. However, as more stimulus components are added to this relatively simple experiment, interactions among components produce a more complex pattern of results. An intense forward masker, while not causing any threshold shift for the test tone, produces a nonmonotonic intensity discrimination function [“the midlevel hump,” Zeng et al., Hearing Res. 55, 223–230 (1991)]. The midlevel hump can be removed by the presence of additional notched noise [Plack and Viemeister, J. Acoust. Soc. Am. 92, 1902–1910 (1992)] or narrow-band noise whose level is increased along with the test tone’s standard level. The same midlevel hump can also be enhanced by a fixed-low-level notched noise or a high-level, high-pass noise which causes minimal masking at the test frequency. Interactions of forward masking and simultaneous masking present a serious problem for a clear interpretation of these results. For example, the notched noise was originally intended to restrict off-frequency listening, but on-frequency masking compromised this original purpose and confounded the interpretation of the notched noise effects. By measuring systematically the growth-of-masking functions, the present study identified various interactions of forward and simultaneous masking and clarified the role of off-frequency listening in forward-masked intensity discrimination. Both peripheral and central mechanisms may have contributed to the occurrence, reduction and enhancement of the midlevel hump under these masking conditions.
Oil for food

Amidst fear of food shortages, prices slash upwards, doubling and redoubling in a year's span. The arid countries can respond least to such scarcities, most of all the richer and more parched natio...
Infected pancreatic pseudocysts with colonic fistula formation successfully managed by endoscopic drainage alone: report of two cases

Fistulization of pancreatic pseudocysts into surrounding viscera is a well-known phenomenon and usually requires surgical management. We report two cases of pancreatic pseudocysts that developed spontaneous fistulas to the colon with resulting fever and abdominal pain. The patients were managed nonoperatively with a combination of endoscopic drainage and antibiotics, and their pseudocysts and fistulas resolved. The patients have remained symptom-free for a mean of 14 months of follow-up.
Modeling Nanoparticle Internalization via Receptor-Mediated Endocytosis

In recent years there has been an enormous interest in using receptor-mediated endocytosis (RME) for cellular delivery of nanoparticles (NPs). In this approach, NPs containing a certain load (drug molecules, RNA, etc.) are coated with appropriate ligands that allows them to get internalized via RME. The internalized NPs then can be used for various biomedical applications including imaging, biosensing and targeted drug delivery.Current theoretical models proposed to explain NP internalization via RME are based on the hypothesis that the wrapping of a NP is driven by the formation of bonds between receptors (on cell surface) and ligands (on NP). We explore an alternative hypothesis: We propose that the wrapping of a NP is driven by the assembly of a protein coat that forms on the cytoplasmic side of the cell membrane during RME. Using a simple model of coat assembly that we proposed earlier (Banerjee et al., Biophys. J. 102, 2725 (2012)) we study the kinetics of NP internalization. In particular, we calculate how the wrapping probability and the mean wrapping time depend on the size of a NP. We compare our results with experimental data and those of other theoretical models.
Unidirectional replication in Escherichia coli of three small plasmids derived from R factor R12.

Abstract Replicating molecules of three small plasmids, pSM1, pSM2, and pSM3, were isolated from a CsCl density gradient containing ethidium bromide. These plasmids are all derived from R12, a mutant of NR1 (same as R100). By means of pulse-labeling experiments, the replicating forms were located at buoyant densities intermediate between those of the closed circular and open circular DNA bands. These molecules were analyzed by electron microscopy following digestion with restriction endonucleases. Digestion of pSM2 with EcoR1 and with HindIII revealed the presence of a single origin of replication located 1.72 kilobases (kb) from the EcoR1 cutting site (2.04 kb from the HindIII cutting site). These experiments also demonstrated that replication occurs in a unidirectional mode from the origin. Analysis of EcoR1-cleaved replicating molecules of pSM1 and pSM3, which carry common sequences completely or partly homologous to pSM2, provides further evidence for the unidirectional replication of these plasmids from a common origin. The site of the origin of replication was fixed at 85.5 on the kilobase map of R100. This origin, which is located in the RTF region, probably corresponds to one of the replication origins of R100.
A Study of Optimal Abstract Jamming Strategies vs. Noncoherent MFSK

We introduce an abstract model for studying MFSK jammers. We conclude that Houston's partial-band tone jammers are optimal among all energy-restricted jamming threats vs. orthodox MFSK, but that if the communicator uses random amplitude modulation as a countermeasure, a gain of 3dB vs. optimal jamming (which is no longer tone jamming) is achievable.
Developmental Expression of Monocyte (MN) Early Growth Response-1 Gene(EGR-1) in Response to Lipopolysaccharide (LPS) and Nitric Oxide (NO) |[dagger]| 320

The maturation of monocyte function across gestational age is an important factor in the host response of preterm and term newborns to infectious and non-infectious agents. EGR-1 is essential in promoting cell differentiation of progenitor cells to macrophages. LPS stimulates MN immune function and EGR-1 expression. Nitric oxide modulates EGR-1 expression and induces MN differentiation. Investigating the developmental expression of EGR-1 in response to LPS and to NO is relevant to our study of development of monocyte immune responses. Freshly isolated cord blood MN and peripheral blood mononuclear cells (PBMC) were stimulated with 10μg/ml LPS for 2.5 hrs or preincubated with a NO donor,S-nitroso-N-acetylpenicillamine (SNAP, 0.5mM) for 30 min, then stimulated with LPS in cell culture. Northern analysis and slot blots of mRNA for EGR-1 were performed using a 32P labeled cRNA probe for human EGR-1. In Northern blots of PBMC mRNA, EGR-1 expression increased from baseline when preterm, term and adult cells were stimulated with LPS. In slot blots of MN mRNA, EGR-1 expression again increased with LPS stimulation. With SNAP pretreatment, EGR-1 expression in response to LPS was blunted in adult MN whereas expression was increased in term and preterm cells. These results were confirmed with densitometry scanning. The neonatal samples had a clear increase in EGR-1 expression when pretreated with the NO donor when compared to stimulation with LPS alone. Nitric oxide modulation of the effect of LPS on EGR-1 expression is developmentally regulated. Understanding the developmental aspects of monocyte responses to the oxidant stress in various disease states will be important in the pursuit of efficacious therapies for the newborn at varying levels of maturation.
The electrical conductivity of doped and undoped uranium oxide

The conductivity of undoped and doped uranium dioxide was investigated over the temperature range of approximately 300–1600 K. Activation energies calculated for the undoped samples and those doped with Cr2O3 and Gd2O3 are in agreement with previously published values. The values calculated for TiO2- and La2O3-doped samples were nearly twice that for the undoped UO2. The addition of Nb2O5 resulted in the extension of the intrinsic region of conductivity to lower temperatures than had been previously reported. The dependence of the extrinsic conductivity of Gd2O3- and Cr2O3-doped samples on the dopant level supports an impurity compensation model of conduction.
The normal QRS vectorcardiogram in infants and children from birth to fifteen years

Abstract One hundred sixty-six QRS vectorcardiograms from 154 patients with normal hearts have been analyzed according to morphology and rotation of the loop and position of the 0.02, 0.03, 0.04 and 0.05 second instantaneous vectors. The patients' age ranged from birth to fifteen years inclusive. The vectorcardiograms were taken with an apparatus similar to that of Shillingford and Brigden using the cube system of Grishman. Variations in the morphology and rotation of the QRS loop are not uncommon in the first month of life. The “transition” period has also considerable variation as to the time of onset and termination. As a rule, in the horizontal plane of the cube system, counterclockwise rotation should be seen at four months and the figure of eight pattern should be absent at ten years in a normal vectorcardiogram. At three months and over, the 0.03 second instantaneous vector normally should not be directed to the right. The horizontal plane of the cube system of Grishman gives the most information relative to the progressive changes in the QRS loop from birth to fifteen years.
Micromechanisms of fatigue crack growth retardation following overloads

New mechanistic interpretations to rationalize fatigue crack growth retardation due to load excursions are presented. It is reasoned that crack closure arising from residual tensile displacements is not the primary mechanism for growth attenuation following a peak tensile overload. A new mechanism for retardation is discussed in terms of a “micro-roughness” model. Quantitative analyses are provided to estimate the extent of reductions in effective driving force in the retarded growth region due to possible crack branching and fracture face micro-roughness. It is argued that the retarded crack advance is effectively governed by the micromechanisms of Stage I growth although nominally Stage II conditions exist in the post-overload zone. The implications of the present arguments are shown to be consistent with a number of typical post-overload phenomena cited in the literature.
A report on the Fourth Conference on Transport Theory

A summary of the conference is given, including the conference program and highlights of the technical sessions. Topics in the technical sessions include: discussion of the mono-energetic transport equation with isotropic scattering in two-dimensional geometry; the slab transport equation; the spectrum of the transport operator for time-dependent slowing down problems; the resolvent integration method to the multigroup transport operator; the multigroup transport operator with anisotropic scattering; asymptotic methods applied to the transport equation; the Hilbert space approach to the transport operator in multiplying media; the criticality problem for a reflected slab in a two-group approximation, using the original singular eigenfunction method; the critical slab multigroup transport problem; a new symmetry group for the neutron transport equation; the extension of the transfer matrix method to treat transport problems in spherical geometry; a three-dimensional problem with continuous energy dependence and isotropic scattering; a space-time stability analysis of a nuclear reactor with nonlinear feedback effects; derivation of diffusion-type equations for the ''self'' Green's function of a particle in a liquid; the linearized Boltzmann equation of rarified gas dynamics with the linear BGK model of molecular interaction; the motion of a sphere through a fluid; kinetic theory; error analysis of coarse network calculations withmore » transport computer codes; and diffusion of binary gas mixtures. (GHT)« less
Input statistics and hebbian cross-talk effects

As an extension of prior work, we studied inspecific Hebbian learning using the classical Oja model. We used a combination of analytical tools and numerical simulations to investigate how the effects of synaptic cross talk which we also refer to as synaptic inspecificity depend on the input statistics. We investigated a variety of patterns that appear in dimensions higher than two and classified them based on covariance type and input bias. We found that the effects of cross talk on learning dynamics and outcome is highly dependent on the input statistics and that cross talk may lead in some cases to catastrophic effects on learning or development. Arbitrarily small levels of cross talk are able to trigger bifurcations in learning dynamics, or bring the system in close enough proximity to a critical state, to make the effects indistinguishable from a real bifurcation. We also investigated how cross talk behaves toward unbiased "competitive" inputs and in which circumstances it can help the system productively resolve the competition. Finally, we discuss the idea that sophisticated neocortical learning requires accurate synaptic updates similar to polynucleotide copying, which requires highly accurate replication. Since it is unlikely that the brain can completely eliminate cross talk, we support the proposal that is uses a neural mechanism that "proofreads" the accuracy of the updates, much as DNA proofreading lowers copying error rate.
Agricultural Policy in an Urban Society

D URING the past four years some leading members of this association have expressed a profound malaise concerning the institutional setting in which agricultural policies must now be made. This malaise is justified. Cochrane predicted in 1964 that "increased agricultural productivity is going to drive farm program costs, under voluntary control programs, into direct collision with the budget limitation objectives of the urban voter within the next three to ten years. A crisis in commercial farm policy is in the making" [8, p. 460]. Bonnen, in 1965, concluded that the whole complex of institutions constituting (in his words) the Agricultural Establishment is in danger of imminent demise:
Posterior Reversible Encephalopathy Syndrome: Incidence of Atypical Regions of Involvement and Imaging Findings

OBJECTIVE. Posterior reversible encephalopathy syndrome (PRES) is classically characterized as symmetric parietooccipital edema but may occur in other distributions with varying imaging appearances. This study determines the incidence of atypical and typical regions of involvement and unusual imaging manifestations.MATERIALS AND METHODS. Seventy-six patients were eventually included as having confirmed PRES from 111 initially suspected cases, per imaging and clinical follow-up. Two neuroradiologists retrospectively reviewed each MR image. Standard sequences were unenhanced FLAIR and T1- and T2-weighted images in all patients, with diffusion-weighted imaging (n = 75) and contrast-enhanced T1-weighted imaging (n = 69) in most. The regions involved were recorded on the basis of FLAIR findings, and the presence of atypical imaging findings (contrast enhancement, restricted diffusion, hemorrhage) was correlated with the severity (extent) of hyperintensity or mass effect on FLAIR.RESULTS. The incidence of regio...
Toxicity Analysis of Postoperative Image-Guided Intensity-Modulated Radiotherapy for Prostate Cancer

Purpose To report on the acute and late gastrointestinal (GI) and genitourinary (GU) toxicity associated with a unique technique of image-guided radiotherapy (IGRT) in patients undergoing postprostatectomy irradiation. Methods and Materials Fifty patients were treated with intensity-modulated radiation therapy (IMRT) after radical prostatectomy. Daily image guidance was performed to localize the prostate bed using kilovoltage imaging or cone-beam computed tomography. The median prescription dose was 68 Gy (range, 62–68 Gy). Toxicity was graded every 3 to 6 months according to the Common Terminology Criteria for Adverse Events version 3.0. Results The median follow-up was 24 months (range, 13–38 months). Grade 2 acute GI and GU events occurred in 4 patients (8%) and 7 patients (14%), respectively. No Grade 3 or higher acute GI or GU toxicities were observed. Late Grade 2 GI and GU events occurred in 1 patient (2%) and 8 patients (16%), respectively. Only a single (2%) Grade 3 or higher late toxicity was observed. Conclusions Image-guided IMRT in the postprostatectomy setting is associated with a low frequency of acute and late GI/GU toxicity. These results compare more favorably to radiotherapy techniques that do not use in-room image-guidance, suggesting that daily prostate bed localization may reduce the incidence of adverse events in patients undergoing postprostatectomy irradiation.
Test of the inverse Compton model for Cygnus X-1

The unsaturated Compton model for Cygnus X-1 is attractive as it accounts for the power law spectrum with index (alpha) approximately equal to 1, and for the alleged high electron temperature (greater than 1 billion K). A critical test for the model is proposed, utilizing spectral data and especially the transition data when Cyg X-1 exhibited anticorrelated variations in soft and hard X-ray luminosities, with the pivoting point at about 10 keV; it is shown that the hard X-ray data available to date strongly support this model.
Size effect, material ductility and shape of fracture process zone in quasi-brittle materials

Abstract Numerical three-point bending tests were conducted on a softening material model to study the effect of specimen size and material ductility on the shape of the fracture process zone. A bonded particle model (BPM) was used for simulation of the rock. The particles at the contact points were allowed to follow a softening behavior to be able to capture the initiation and development of the process zone. Five different beam sizes of 20 (height) × 60 (span), 40 × 120, 80 × 240, 160 × 480, and 320 × 960 mm 2 were used. All beams had a notch at their mid-span to study the mode I fracturing of rock. For each specimen size, six different realizations were introduced to study the effect of particle arrangement on the induced damage zone. The material ductility was controlled and modified by introducing different slopes for the post peak behavior of the contact points between the particles. The shape of the process zone was obtained by calculating both the width and the length of the process zone at the peak load. The results suggest that as the specimen size increases, the process zone expands in its size. In addition, the results indicate that for quasi-brittle materials, the length to width ratio of the process zone is greater compared to that of ductile materials. Furthermore, it is shown that the sizes of the representative elemental volumes corresponding to the width and the length of the process zone may not be identical in the quasi-brittle materials.
The dissolution of benzene, toluene, m-xylene and naphthalene from a residually trapped non-aqueous phase liquid under mass transfer limited conditions

The results of dissolution experiments for benzene, toluene, m-xylene and naphthalene (BTXN) from a relatively insoluble oil phase (tridecane), residually trapped in a non-sorbing porous medium, are described. This mixture was chosen to simulate dissolution of soluble aromatic compounds from a petroleum hydrocarbon mixture, e.g., crude oil, for which a large fraction of the mixture is relatively insoluble. The experiments were carried out at a small source length to interstitial velocity ratio, L/v, so that dissolution would be mass transfer limited (MTL). When fitted to data for toluene, a multiregion mass transfer model was found to predict the experimental data satisfactorily for the other components without adjustment of the mass transfer rate parameters. These results indicate that the dissolution process can be generalized for various hydrophobic organic compounds present in a multicomponent non-aqueous phase liquid (NAPL) when mass transfer limitations are present. This also suggests that dissolution data obtained for one compound can be useful for predicting the dissolution histories for other compounds from petroleum hydrocarbon mixtures.
“Take Five” Nutrition Fair Markets Nutrition in a University Residence Hall Dining Center

Abstract A "Take Five" nutrition fair coordinated by Community Nutrition graduate students in partnership with Dining Services, was conducted in a university residence hall dining center to increase resident students' awareness, knowledge and consumption of fruits and vegetables (F/V) and to increase graduate students' skills in program planning, implementation and evaluation. A student focus group and consultation with Dining Services staff were used to determine audience interests. Developed by graduate students, a web site linked to the Dining Services web site served to promote activities and provide nutrition information. On the day of the fair, students who called the menu hotline heard not only the daily menu options, but an announcement about the activities. Interactive programs, posters, table tents and displays related to benefits of increased F/V consumption, making healthful F/V choices from the menu and healthful snacks students can make or select in the residence hall. Salad bars featured fruit and vegetable trays with traditional favorites as well as less familiar choices. Recipes and samples of low fat F/V dips and a dried fruit snack mix were distributed. Evaluation included observation and written evaluation from participants and class members. Presenters and staff observed students participated in activities and made positive comments about F/V selections. Written evaluations from 87 students show that 62% said they would prepare/eat one of the snacks shown, 46% stated "yes" and 37% "maybe" they would eat more F/V most days. Student evaluations identify teamwork as a program strength.
Gene Cluster Statistics with Gene Families

Identifying genomic regions that descended from a common ancestor is important for understanding the function and evolution of genomes. In distantly related genomes, clusters of homologous gene pairs are evidence of candidate homologous regions. Demonstrating the statistical significance of such “gene clusters” is an essential component of comparative genomic analyses. However, currently there are no practical statistical tests for gene clusters that model the influence of the number of homologs in each gene family on cluster significance. In this work, we demonstrate empirically that failure to incorporate gene family size in gene cluster statistics results in overestimation of significance, leading to incorrect conclusions. We further present novel analytical methods for estimating gene cluster significance that take gene family size into account. Our methods do not require complete genome data and are suitable for testing individual clusters found in local regions, such as contigs in an unfinished assembly. We consider pairs of regions drawn from the same genome (paralogous clusters), as well as regions drawn from two different genomes (orthologous clusters). Determining cluster significance under general models of gene family size is computationally intractable. By assuming that all gene families are of equal size, we obtain analytical expressions that allow fast approximation of cluster probabilities. We evaluate the accuracy of this approximation by comparing the resulting gene cluster probabilities with cluster probabilities obtained by simulating a realistic, power-law distributed model of gene family size, with parameters inferred from genomic data. Surprisingly, despite the simplicity of the underlying assumption, our method accurately approximates the true cluster probabilities. It slightly overestimates these probabilities, yielding a conservative test. We present additional simulation results indicating the best choice of parameter values for data analysis in genomes of various sizes and illustrate the utility of our methods by applying them to gene clusters recently reported in the literature. Mathematica code to compute cluster probabilities using our methods is available as supplementary material.
349 THE EFFECT OF CHLOROTHIAZIDE (CT) ON LAS IX-INDUCED HYPERCALCIURIA

Infants with chronic lung disease often develop rickets secondary to prolonged lasix (L) treatment. We studied the effect of CT on the hypercalciuric response to L in 11 young adult rats (Wt 259±1.1 gm, M±SE). The rats were fed Purina rat chow and received water ad lib. At the end of a 15 day control period, urine was collected for 72 hrs. The rats were then divided into 2 groups: Group I (n=5) received 15 mg/kg/d of L IP and Group II (n=6) received 20 mg/kg/d of CT IP for 15 d, at the end of which a 72 hr urine collection was performed. Following this all rats received both drugs at the above dosage and a third 72 hr urine collection was done at the end of a 15 d treatment period. Each urine collection was analyzed for Ca concentration. Urinary Ca excretion data (mg/kg/d) are displayed below. We conclude that administration of L produces a 50% increase in urinary Ca excretion compared to control. However, the combination of L and CT caused a 24% reduction in urinary Ca excretion when compared with L alone. Urinary Ca excretion with CT alone was not significantly different than control. These data support the use of both CT and L therapy in infants with chronic lung disease when diuretic therapy is needed.
AN ANTIBODY AGAINST REVERTANT FORMS OF CELL-WALL-DEFICIENT BACTERIAL VARIANT IN SERA FROM PATIENTS WITH CROHN'S DISEASE

Abstract Sera from patients with Crohn's disease or ulcerative colitis, and from controls were examined by indirect immunofluorescence for antibody against two strains of pseudomonas-like cell-wall-defective bacterial variants. Serum samples from 22 of 25 patients with Crohn's disease produced fluorescence of both revertant cell-wall-defective bacterial strains. Intensity of fluorescence correlated positively with the degree of disease activity. Sera from 23 patients with ulcerative colitis and from 15 control subjects did not produce any significant staining of either of the two revertant cell-wall-defective bacterial strains. Absorption of sera with Escherichia coli, Bacteroides thetaiotomicron, and Pseudomonas aeruginosa did not alter the intensity of fluorescence in patients with Crohn's disease, whereas similar absorption of sera from patients with ulcerative colitis and controls abolished the slight staining of cell-wall-defective strains produced by 29% of unabsorbed serum samples.
End Users Who Meet Their Own Requirements

Over the past 25 years, user interface designers and usability engineers have studied and refined human-computer interaction techniques with the goal of improving people's productivity and experience. One result is an increasing number of tools designed to help end users build or customize software solutions for a variety of everyday problems -- from email filters, to spreadsheet simulations, to interactive web applications. How far can end users go in meeting their own software requirements? Given the right tools, people and organizations may be able to rapidly develop solutions to a huge number of context-specific computing requirements, eliminating the wait for IT professionals to analyze and engineer a solution. But is this a good thing? End-user programmers are not trained in software engineering or computing paradigms. They have little intrinsic motivation to test their constructions for even basic concerns like correctness or safety. In this talk I argue that the transformation of end users into software developers is well underway and discuss the prospects for maximizing the benefits to society while addressing the risks.
Reference drug programs: Effectiveness and policy implications

In the current economic environment, health care systems are constantly struggling to contain rapidly rising costs. Drug costs are targeted by a wide variety of measures. Many jurisdictions have implemented reference drug programs (RDPs) or similar therapeutic substitution programs. This paper summarizes the mechanism and rationale of RDPs and presents evidence of their economic effectiveness and clinical safety. RDPs for pharmaceutical reimbursement are based on the assumption that drugs within specified medication groups are therapeutically equivalent and clinically interchangeable and that a common reimbursement level can thus be established. If the evidence documents that a higher price for a given drug does not buy greater effectiveness or reduced toxicity, then under RDP such extra costs are not covered. RDPs or therapeutic substitutions based on therapeutic equivalence are seen as logical extensions of generic substitution that is based on bioequivalence of drugs. If the goal is to achieve full drug coverage for as many patients as possible in the most efficient manner, then RDPs in combination with prior authorization programs are safer and more effective than simplistic fiscal drug policies, including fixed co-payments, co-insurances, or deductibles. RDPs will reduce spending in the less innovative but largest market, while fully covering all patients. Prior authorization will ensure that patients with a specified indication will benefit from the most innovative therapies with full coverage. In practice, however, not all patients and drugs will fit exactly into one of the two categories. Therefore, a process of medically indicated exemptions that will consider full coverage should accompany an RDP. In the current economic environment, health care systems are constantly struggling to contain rapidly rising costs. Drug costs are targeted by a wide variety of measures. Many jurisdictions have implemented reference drug programs, and others are considering them. This paper summarizes the mechanism and rationale of RDPs, presents evidence of their economic effectiveness and clinical safety, and concludes with some practical implications of implementing RDP policies.
Meat goat kids finished on alfalfa, red clover or orchardgrass pastures: Carcass merit and meat quality

This experiment was conducted in 2005-2007 to evaluate carcass and chevon (goat meat) quality parameters when meat-goat kids (n=72) were finished on alfalfa (Medicago sativa L; ALF); red clover (Trifolium pratense L.; RCG); or orchardgrass (Dactylis glomerata L.; OGR) pastures. Carcass conformation score was greater (P=0.08) when meat-goat kids were finished on ALF compared to OGR with RCG intermediate. Chevon meat samples from goats finished on the three pasture treatments did not differ in ash, intramuscular fat, or crude protein content or in concentrations of omega6 and omega3 fatty acids, or the omega6 to omega3 ratio. Goats finished on OGR had higher (P<0.001) 18:1 trans-11 fatty acids (FA) compared to ALF or RCG. Overall, meat-goat kids finished on ALF, RCG, or ORG produced desirable carcass weights for most niche markets in the USA. Chevon is a low-fat meat option with high desirable fatty acids for human diets.
α1-Adrenergic receptors in the nucleus tractus solitarii region of rats with experimental and genetic hypertension

Abstract The binding of theα1-adrenergic receptors antagonist,125I-HEAT, to membranes of nucleus tractus solitarii (NTS) regions of the brains of neurogenic hypertensive, spontaneously hypertensive (SH), and deoxycorticosterone (DOCA)/salt hypertensive rats and their respective controls was studied to quantitate the expression ofα1-adrenergic receptors. Scatchard analysis of the binding studies revealed a 1.8-fold increase in theBmax ofα1-adrenergic receptors in NTS region membranes of SH rats when compared to their Wistar-Kyoto (WKY) control without significant difference in theKd for125I-HEAT. A decrease in theKd with no difference inBmax of receptors125I-HEAT was observed in the NTS region membranes of neurogenic hypertensive rats when compared with their sham-operated controls. In contrast, comparison of theBmax andKd values for125I-HEAT binding in NTS region membrane of the DOCA/salt hypertensive rats and its sham-operated control showed no significant differences. We suggest that alterations in baroreceptor afferent activity may be related to alterations in centralα1-adrenergic receptors binding in SH rats and rats with neurogenic hypertension.
In vivo stability, maturation and relative differential synthesis rates of individual ribosomal proteins in Escherichia coli B/r

The relative differential synthesis rates† of individual ribosomal proteins (r-proteins) were determined for Escherichia coli B/r growing in succinate medium (growth rate, μ = 0.65 doublings per hour), glucose medium (μ = 1.36) and glucose-amino acids medium (μ = 1.90). These differential synthesis rates were found to increase co-ordinately with increasing bacterial growth rates; this implies that ribosomes from bacteria growing at different rates are homogeneous with respect to their protein composition (i.e. the stoichiometric amounts of the different r-proteins per ribosome are constant and independent of the bacterial growth rate). Following incorporation into ribosomes, the bulk of the r-proteins were found to be as stable as total protein. Only two r-proteins, S6 and S21, were less stable than total protein; their decay half-lives, measured in succinate and glucose-amino acids cultures, were estimated to be approximately 500 minutes. In addition, post-translational modification of proteins S18, L6 and L11 was observed and the possible relations between modification and in vivo ribosome assembly are discussed. Finally, evidence is presented suggesting that the coordinate production of r-proteins may result, in part, from a mechanism that degrades excess r-proteins that are not rapidly incorporated into ribosomal particles.
PTHrP Expression in Chondrocytes, Regulation by TGF-β, and Interactions between Epiphyseal and Growth Plate Chondrocytes

Abstract Although PTHrP has been identified as a key regulator of chondrocyte differentiation in the growth plate, the factors directly regulating PTHrP expression have not been identified. Furthermore, while cells from the epiphysis are considered the physiologic source of PTHrP, the relative expression of PTHrP in epiphyseal and growth plate chondrocytes has not been defined. PTHrP expression was examined in chondrocytes isolated from 3- to 5-week-old chick long bones. The expression of PTHrP mRNA was 10-fold higher in epiphyseal chondrocytes compared to cells from the growth plate. Growth plate chondrocytes were isolated into populations with distinct maturational characteristics by countercurrent centrifugal elutriation and analyzed for PTHrP expression. The expression was highest in the least mature cells and progressively declined with the onset of maturation. The regulation of PTHrP expression was further examined in epiphyseal chondrocytes. Both TGF-β1 and cis -retinoic acid stimulation markedly increased PTHrP mRNA levels, while BMP-2 and PTHrP stimulation decreased the expression of this transcript. The effects of TGF-β1 (8.9-fold stimulation) and TGF-β3 (9.2-fold) were slightly greater than the effects of TGF-β2 (4.9-fold). The effect of TGF-β was dose-dependent and increases could be detected after 68 h of treatment. To analyze the paracrine effect of epiphyseal and growth plate chondrocytes on each other, these cells were placed in coculture and the mRNA from each of the populations was harvested separately after 24 h. Following coculture the PTHrP mRNA levels increased in the epiphyseal cells while the expression of type X collagen and Indian hedgehog transcripts decreased in growth plate chondrocytes. The results demonstrate potentially important paracrine interactions between these cell populations, possibly mediated by TGF-β and PTHrP.
Radar Scattering from Venus at Large Angles of Incidence and the Question of Polar Ice Caps

Spectrum analysis of radar waves backscattered from an anulus near the limb of Venus shows that a uniform scattering model applies over regions extending from the equator to within approximately 15 degrees of the poles. These observations indicate that large polar ice caps extending to latitudes as low as 60 degrees are very unlikely.
Relationship between synaptosomal uptake and release of [14C]gaba, [14C]diaminobutyric acid and [14C]beta-alanine.

[14C]GABA is taken up by rat brain synaptosomes via a high affinity, Na+-dependent process. Subsequent addition of depolarizing levels of potassium (56.2 MM) or veratridine (100 μM) stimulates the release of synaptosomal [14C]GABA by a process which is sensitive to the external concentration of divalent cations such as Ca2+, Mg2+, and Mn2+. However, the relatively smaller amount of [14C]GABA taken up by synaptosomes in the absence of Na+ is not released from synaptosomes by Ca2+ -dependent, K +-stimulation. [14C]DABA, a competitive inhibitor of synaptosomal uptake of GABA (Iversen & Johnson, 1971) is also taken up by synaptosomal fractions via a Na + -dependent process; and is subsequently released by Ca2+ -dependent, K+-stimulation. On the other hand, [14C]β-alanine, a purported blocker of glial uptake systems for GABA (Schon & Kelly, 1974) is a poor competitor of GABA uptake into synaptosomes. Comparatively small amounts of [14C] β-alanine are taken up by synaptosomes and no significant amount is released by Ca2+ -dependent, K+-stimulation. These data suggest that entry of [14C]GABA into a releasable pool requires external Na+ ions and maximal evoked release of [14C]GABA from the synaptosomal pool requires external Ca2+ ions. The GABA analogue, DABA, is apparently successful in entering the same or similar synaptosomal pool. The GABA analogue, β-alanine, is not. None of the compounds or conditions studied were found to simultaneously affect both uptake and release processes. Compounds which stimulated release (veratridine) or inhibited release (magnesium) were found to have minimal effect on synaptosomal uptake. Likewise compounds (DABA) or conditions (Na+-free medium) which inhibited uptake, had little effect on release.