cssi/SciSciGPT-SciSciNet huggingface dataset:
Introduction to the Special Issues in Honor of Salvador Barberà’s 65th birthday

The size and quality of this two-volume special issue in honor of Salvador Barbera speaks to the wide scope of his contributions as a friend, co-author, mentor, and builder. We begin by framing some of Salvador’s important research contributions. The theory of social choice is at the very center of economic analysis. In the late 1960s, following various contributions by William Vickrey, Robin Farquharson, Edward Clarke, Ted Groves, Alan Gibbard and Mark Satterthwaite, the notion of strategy-proofness took form and, together with ideas emerging in game theory, produced an “economics of incentives”. This line of research became among the most fruitful work in all of social science of the last quarter of the twentieth century. Salvador Barbera is among the most influential scholars in this line of research, particularly on the voting models side. He stands among the world leaders. In particular, Salvador Barbera’s work on strategy-proofness has been of fundamental importance and he has made several seminal contributions. These begin with papers that follow from his Ph.D. thesis and are particularly concerned with strategyproofness when one allows some randomization in outcomes. Those papers helped uncover the role of chance or randomization in social decisions, and showed the limited extent to which that can help in mitigating individual incentives for manipulation. That work has recently sparked a series of interesting follow-up papers. Salvador’s other important works on strategy-proofness in such rich domains include insightful proofs based on pivotal voter arguments and extensions to infinite settings (in work with Bezalel Peleg).
Rate of densification of gel during coagulation of viscose

We have developed a simple method which permits measurement of the rate of densification of the gel forming during the coagulation of viscose and in effect experimentally separates the coagulation process from the regeneration process. The method is based on changes in density of a drop of viscose as it passes through a column of a salt solution. In devising the experimental program, three assumptions have been made: (1) Stokes' law is assumed to be valid for the movement of a drop of viscose through a column of a salt solution; (2) the volumes of sodium cellulose xanthate and water are assumed additive in viscose, permitting the calculation of the density of anhydrous xanthate; (3) the mechanics of loss of water initially from a surface are assumed to be the same whether the area is planar or spherical, i.e., a drop of viscose initially dehydrates in the same manner as does a thin film. Using this experimental technique, we have studied the coagulation of viscose as a function of salt index, ripening temperature, type of salt, and concentration of salt.
Surrender as a Developmental Achievement in Couple Systems

This article explores the concept of surrender in couple relationships. It proposes that the ability to allow oneself to “surrender” to one's partner is a developmental achievement that enhances intimacy between partners. Rather than conceptualizing the act of surrender as an indication of submissive behavior and/or the abuse of power dynamics in the relationship, it is argued that surrender can be growth promoting for individuals in the context of their relationship. The article expands the conceptualization of Emmanuel Ghent's (1990) classic paper that differentiated the concepts of masochism, submission, and surrender. The concepts of the paper are illustrated in a summary of clinical work with a heterosexual couple.
Ion-ion hybrid Alfvén wave resonator demonstrated

[1] Theoretical calculations have indicated that in magnetized plasmas with two ion species, Alfven waves, oscillations of the magnetic field due to plasma currents, can become trapped in a resonator. Such a resonator has now been demonstrated for the first time in a laboratory. Vincena et al. created the resonator in a magnetized plasma with hydrogen and helium ions. Their observations agreed well with theoretical predictions. Similar resonators could occur in the magnetosphere around Earth and other planets, where the resonant modes can interact with energetic particles. (Geophysical Research Letters, doi:10.1029/2011GL047399, 2011)
An evaluation of environmental disclosures made in corporate annual reports

Abstract This paper evaluates the quality and accuracy of environmental disclosures made in corporate annual reports. Annual report disclosures made by 26 firms in environmentally sensitive industries are examined. An indexing procedure is used to measure the contents of the disclosures, and the relationship between the disclosure contents and the firms' environmental performance is tested. The study provides a detailed measure of environmental disclosure contents. Results indicate that corporate environmental disclosures are incomplete and are not related to the firms' actual environmental performance.
Synchronization of conference presentation sequence using delay equalization approach

In this paper, a delay equalization approach is proposed for cohesive conference presentation with minimal screen- freezing effect. The underlying screen-freezing effect is due to varying delays in the communication channels involved in broadcasting. In turn, this poses a threat to the goal of uniform delay distribution among data packets for synchronized presentation broadcast. We wish to achieve uniformity among packet arrival times to the recipients. This objective is achieved by transforming a given input delay distribution (D) to the desired output density through a delay equalization process. Considering a general case of between packet and frame delay distributions for a given input, the desired output is obtained through a delay equalization process. In case of a specific normal delay distribution, a memory-less system g(D) is determined as an approximation to the delay equalizer such that the equalizer output O(t)equalsg[D(t)] is uniformly distributed in the allowable delay limits of (a,b) assuring the specified quality of service (QoS) parameters. The corresponding delay is added at each recipient workstation, which acts as the wait period required before it begins its designated presentation.For a zero mean normal delay density case, the equalizer transfer function can be given in a closed from solution as O(t)equalsg[D(t)[equals(b-a)]0.5+eft(-D/$RO OTR(0)))[+a, where erf(x) is the standard error function. The histogram approximation is adopted as an asymptotically delay equalization means for general cases. This technique provides a means for modifying the dynamic range of data acquired by altering it into a desired distribution. In experimentation, equalizer characteristic functions are derived for a set of selected input delays to obtain the desired output. The delay equalizer system developed here is suited for deployment in a distributed hierarchical conferencing environment. To accommodate a broadcast continuity, the multimedia presentation is provided with a shared workspace among the web servers acting as administrators in the network. The arrival times and the presentation durations of the data packets at the recipient workstations are recorded in this shared workspace. For a case study, a Poisson distribution type delay density is selected to be the input for the delay equalizer with the desired output to be uniformly distributed. The transfer function input and output distributions are derived and depicted in a parametric form for different values of mean in the simulation results to illustrate the effectiveness of the equalization process. We have demonstrated that this method is appropriate for equalizing the lumped communication channel delays. Further work is in progress for developing the distributed channel delay equalization.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Polymer Sliding in Axons

In axons the cytoskeletal polymers are transported by slow axonal transport. Microtubules, microfilaments and neurofilaments move at different rates in the axon. On the basis of their transport rates, two populations of polymers can be distinguished: SCb polymers are transported at 2-4 mm day-1 and SCa polymers are transported at 0.25-1 mm day-1. As they move within the axon, the faster moving SCb polymers must pass the slower moving SCa polymers. This observation and others indicate that polymers slide in the axon. A model of polymer sliding is presented. This model provides a dynamic architectural framework for studies of the mechanisms of slow axonal transport.
Going Mobile: A Medical Library's Outreach Strategy

This article addresses the planning, implementation, and recommendations of one medical library in reaching out to users in the mobile environment. A three-pronged approach was adopted by the Mobile Committee that addressed this issue and included the creation of a mobile web page , Mobile LibGuide , and recurring library drop-in support sessions targeted at specific student populations. Attendance at drop-in sessions was popular as was the use of the Mobile LibGuide. Increased use of the mobile web page is anticipated as a result of inclusion in The George Washington University Mobile App in spring 2011.
High functioning male with fragile X syndrome and fragile X-associated tremor/ataxia syndrome

Fragile X syndrome (FXS) affects individuals with more than 200 CGG repeats (full mutation) in the fragile X mental retardation 1 (FMR1) gene. Those born with FXS experience cognitive and social impairments, developmental delays, and some features of autism spectrum disorders. Carriers of a premutation (55-200 CGG repeats) are generally not severely affected early in life; however, are at high risk of developing the late onset neurodegenerative disorder, Fragile X-associated Tremor/Ataxia Syndrome (FXTAS), or Fragile X-associated Primary Ovarian Insufficiency (FXPOI), and may have other medical conditions such as developmental delay, autism spectrum disorders, hypertension, anxiety, and immune-mediated disorders. Here we present a case of a 58-year-old man with a borderline IQ, average memory skills, and executive function deficits. He met criteria for multiple psychiatric diagnoses and presented with tremor and ataxia, meeting criteria for FXTAS. Molecular testing unveiled a completely unmethylated FMR1 full mutation in peripheral blood mononucleated cells with elevated FMR1 mRNA and premutation alleles of different sizes in two other tissues (primary fibroblasts and sperm), indicating the presence of allele instability based on both inter- and intra-tissue mosaicism. The observation of FXTAS in this case of a full mutation mosaic man suggests that the pathogenic mechanism underlying this disorder is not observed exclusively in premutation carriers as it was originally thought. The concomitant presence of features of FXS and late onset neurological deterioration with probable FXTAS likely result from a combined molecular pathology of elevated FMR1 mRNA levels, a molecular hallmark of FXTAS and low FMRP expression that leads to FXS.
Temperature measurement in microfluidic systems using a temperature-dependent fluorescent dye.

A technique is described for the measurement of fluid temperatures in microfluidic systems based on temperature-dependent fluorescence. The technique is easy to implement with a standard fluorescence microscope and CCD camera. In addition, the method can be used to measure fluid temperatures with micrometer spatial resolution and millisecond time resolution. The efficacy of the method is demonstrated by measuring temperature distributions resulting from Joule heating in a variety of microfluidic circuits that are electrokinetically pumped. With the equipment used for these measurements, fluid temperatures ranging from room temperature to 90 °C were measured with a precision ranging from 0.03 to 3.5 °Cdependent on the amount of signal averaging done. The spatial and temporal resolutions achieved were 1 μm and 33 ms, respectively.
Use of Intraoperative Computed Tomography Scanning in Determining the Magnitude of Arthroscopic Osteochondroplasty

Femoroacetabular impingement has recently become a recognized cause of disability and hip arthritis. Hip arthroscopy and femoroacetabular reshaping have been performed to treat this condition. Quantification of the excess femoral and acetabular bone requiring resection has been challenging with the less invasive arthroscopic technique. We describe the use of intraoperative computed tomography assessing osteochondroplasty during arthroscopic surgery to treat cam- and pincer-type femoroacetabular impingement. We also describe the technical steps and present the important radiologic findings we have been able to visualize. We found intraoperative computed tomography scanning to be a reliable and reproducible method of assessing the quality of femoroacetabular impingement surgery. We believe that femoroacetabular impingement surgery can be assessed intraoperatively by use of computed tomography scanning where corrections can be made if necessary.
Proportional hazards models based on biased samples and estimated selection probabilities.

In non-randomized biomedical studies using the proportional hazards model, the data often constitute an unrepresentative sample of the underlying target population, which results in biased regression coefficients. The bias can be avoided by weighting included subjects by the inverse of their respective selection probabilities, as proposed by Horvitz & Thompson (1952) and extended to the proportional hazards setting for use in surveys by Binder (1992) and Lin (2000). In practice, the weights are often estimated and must be treated as such in order for the resulting inference to be accurate. The authors propose a two-stage weighted proportional hazards model in which, at the first stage, weights are estimated through a logistic regression model fitted to a representative sample from the target population. At the second stage, a weighted Cox model is fitted to the biased sample. The authors propose estimators for the regression parameter and cumulative baseline hazard. They derive the asymptotic properties of the parameter estimators, accounting for the difference in the variance introduced by the randomness of the weights. They evaluate the accuracy of the asymptotic approximations in finite samples through simulation. They illustrate their approach in an analysis of renal transplant patients using data obtained from the Scientific Registry of Transplant Recipients Emploi de mode′les a‵ risques proportionnels en pre′sence de biais et de probabilite′s de se′lection estime′es Dans les applications du modele des risques proportionnels aux donnees d'etudes biomedicales non randomisees, il est frequent que l'echantillon ne soit pas representatif de la population cible sous-jacente, ce qui induit un biais dans les coefficients de regression. Ce biais peut ětre elimine en ponderant les sujets observes par l'inverse de leur probabilite de selection respective, tel que propose par Horvitz & Thompson (1952) et etendu au modele des risques proportionnels pour des donnees d'enquěte par Binder (1992) et Lin (2000). En pratique, les poids sont souvent estimes, ce dont l'inference doit tenir compte pour eviter d'ětre faussee. Les auteurs proposent un modele des risques proportionnels pondere en deux temps dans lequel les poids sont d'abord estimes au moyen d'une regression logistique sur un echantillon representatif de la population cible. Un modele de Cox pondere est ensuite ajuste a l'echantillon biaise. Les auteurs proposent des estimations des parametres de regression et du risque de base cumule. Us determinent les proprietes asymptotiques de ces estimations en tenant compte du changement de variance cause par le caractere aleatoire des poids. Ils font appel a des simulations pour evaluer la precision a taille finie des approximations asymptotiques. Ils illustrent leur propos au moyen de donnees du Registre scientifique des greffes d'organe portant sur des patients ayant subi une transplantation du rein.
Speech Breathing in Able-Bodied Children and Children With Cerebral PalsyA Review of the Literature and Implications for Clinical Intervention

Management of the communication problems of children with cerebral palsy presents many challenges to speech-language pathologists. In this paper, we focus on one aspect of that challenge, speech br...
Alternative splicing of Pax6 in bovine eye and evolutionary conservation of intron sequences.

Abstract Pax-6is essential for eye development and for tissue-specific gene expression within the eye. Splicing of an alternative exon (5a) leads to variant DNA binding specificity in Pax6. Here we show that in the mature bovine eye the relative abundance of the alternative Pax6-5a mRNA varies markedly, particularly between the lens and iris. Additional alternative splicing products were identified which may lead to “domain swapping” or truncation of Pax6 proteins. Comparison of amphibian (Xenopus) and mammalian (bovine)Pax-6genes revealed highly conserved intronic sequences flanking exon 5a, including potential lariat sites which may have a role in the mechanism of alternative splicing.
Investigation of protein expression in magnetic field-treated human glioma cells.

We previously reported phenotypic changes in human breast cancer cells following low-level magnetic field (MF) exposure. Here proteomic methods were used to investigate the biochemical effect of MF exposure in SF767 human glioma cells. Protein alterations were studied after exposure to 1.2 microTesla (µT) MF [12 milliGauss (mG), 60 Hertz (Hz)] ± epidermal growth factor (EGF). SF767 cells were exposed for 3 h to sham conditions (<0.2 µT ambient field strength) or 1.2 µT MF (±EGF; 10 ng/ml). Solubilized protein fractions (sham; 1.2 µT; sham + EGF; 1.2 µT + EGF) were loaded for electrophoresis by 2D-PAGE and stained using a colloidal Coomassie blue technique to resolve and characterize the proteins. Protein patterns were compared across groups via Student's t-test using PDQUEST software. Cell profiles revealed significant alterations in the spot density of a subset of treated cells. Automated spot excision and processing was performed prior to peptide mass fingerprinting proteins of interest. Fifty-seven proteins from the detectable pool were identified and/or found to differ significantly across treatment groups. The mean abundance of 10 identified proteins was altered following 1.2 µT exposure. In the presence of EGF six proteins were altered after low magnetic field treatment by increasing (4) or decreasing (2) in abundance. The results suggest that the analysis of differentially expressed proteins in SF767 cells may be useful as biomarkers for biological changes caused by exposure to magnetic fields. Bioelectromagnetics 28:546–552, 2007. © 2007 Wiley-Liss, Inc.
Evolution of the ribosome at atomic resolution

The origins and evolution of the ribosome, 3–4 billion years ago, remain imprinted in the biochemistry of extant life and in the structure of the ribosome. Processes of ribosomal RNA (rRNA) expansion can be “observed” by comparing 3D rRNA structures of bacteria (small), yeast (medium), and metazoans (large). rRNA size correlates well with species complexity. Differences in ribosomes across species reveal that rRNA expansion segments have been added to rRNAs without perturbing the preexisting core. Here we show that rRNA growth occurs by a limited number of processes that include inserting a branch helix onto a preexisting trunk helix and elongation of a helix. rRNA expansions can leave distinctive atomic resolution fingerprints, which we call “insertion fingerprints.” Observation of insertion fingerprints in the ribosomal common core allows identification of probable ancestral expansion segments. Conceptually reversing these expansions allows extrapolation backward in time to generate models of primordial ribosomes. The approach presented here provides insight to the structure of pre-last universal common ancestor rRNAs and the subsequent expansions that shaped the peptidyl transferase center and the conserved core. We infer distinct phases of ribosomal evolution through which ribosomal particles evolve, acquiring coding and translocation, and extending and elaborating the exit tunnel.
Puercan mammalian systematics and biostratigraphy in the Denver Formation, Denver Basin, Colorado

As a result of the Denver Basin Project, several more fossils of Puercan mammals are reported here from five areas in the Denver Formation: South Table Mountain, Greater Denver, the West Bijou Site, Big Gulch, and Corral Bluffs. Systematic description and discussion are provided for one multituberculate and 11 ungulate taxa, including a new species of Baioconodon . Some taxa represent extensions of previously recognized temporal and geographic ranges. Notably, the ungulate Protungulatum donnae from strata of early Puercan (Pu1) age in the Denver Formation represents the southernmost occurrence of the species, while Oxyclaenus simplex , in probable early Puercan strata of the Denver Formation, appears to represent both a temporal and geographic range extension from middle Puercan (Pu2) strata of the San Juan Basin, New Mexico. Additionally, I report the first occurrence in the Denver Basin of the arctocyonid Loxolophus faulkneri . Refined biostratigraphic interpretations, resulting from new discoveries and incorporating paleomagnetic, palynological, and radioisotopic analyses presented elsewhere, suggest that Puercan interval zones Pu1 and Pu2 are both represented by mammalian faunas in the Denver Formation. Localities at South Table Mountain, as well as the Denver Oxyclaenodon Site (DMNH loc. 299) and Nicole's Mammal Jaw locality (DMNH loc. 2557), are Pu1 correlatives. Discoveries reported here support previous interpretations that the Alexander and South Table Mountain localities are probably similar in age (i.e., Pu1) and are included here in the Littleton fauna. Based upon comparison to other Puercan faunas, the Littleton fauna may be temporally intermediate between typical Pu1 assemblages known north of the Denver Basin and earliest Pu2 assemblages from the Hanna Basin, Wyoming. Alternatively, faunal differences between the Littleton fauna and other Pu1 faunas may reflect ecological and biogeographic differences. The unusually high diversity of ungulates in the Littleton fauna suggests some of the diversification that elsewhere characterizes the onset of Pu2 may already have begun by Pu1 in the Denver Basin. The mammalian assemblage at Corral Bluffs is interpreted here as a probable Pu2 correlative, based upon occurrence of Loxolophus faulkneri, Conacodon entoconus and C. delphae , and absence of Pu3 index taxa. Pu2/Pu3 correlatives (i.e., faunal assemblages that are either Pu2 or Pu3) also are reported here from the Big Gulch area, although more fossils are needed to refine their ages. The present study and others in this issue demonstrate that the Denver Basin is among the few places wherein correlation between Puercan mammalian biostratigraphy and paleomagnetic, palynological, and radioisotopic analyses is an attainable goal.
Effects of multi-photon interferences from internally generated fields in strongly resonant systems

Abstract In studies of various nonlinear optical phenomena, strong resonant features in the atomic or molecular response to multi-photon driven processes have been used to greatly enhance the visibility of otherwise weak higher-order processes. However, there are well defined circumstances where a multi-photon-resonant response of a target system leads to the generation of one or more new electromagnetic fields that can drastically change the overall system response from what would be expected from the imposed laser fields alone. New effects can occur and dominate some aspects of the nonlinear optical response because of the constructive or destructive interference between transition amplitudes along multiple excitation pathways between a given set of optically coupled states, where one of the pathways involve internally generated field(s). Under destructive interference some resonant enhancements can become completely canceled (suppressed). This review focuses on the class of optical interference effects associated with internally generated fields, that have been found to be capable of influencing a very significant number of basic physical phenomena in gas or vapor phase systems. It provides a historical overview of experimental and theoretical developments and a modern understanding of the underlying physics and its various manifestations that include: suppression of multi-photon excitation processes, suppression of stimulated emissions (Raman, hyper-Raman, and optically pumped stimulated emissions), saturation of parametric wave-mixing, pressure and beam-geometry dependent shifting of multi-photon-resonant absorption lines, and the suppression of Autler–Townes splitting and ac-stark shifts. Additionally, optical interference effects in some modern contexts, such as achieving multi-photon induced transparency, establishing single-photon self-interference based induced transparency, and generating entangled single photon states, are reviewed.
The role of bilateral ovarian diathermy by KTP laser in the oligoovulatory patient

Objective: To assess the efficacy of ovarian diathermy in women who respond poorly to clomiphene citrate (CC). Methods: Retrospective analysis of patients who failed to respond to 200 mg of CC and subsquently were treated with KTP laser bilateral ovarian diathermy. Twenty-one patients with a total of 288 cycles were included. Results: The study patients had a mean age of 29.8 ± 5.0 years (n = 21) and a mean body mass index of 35.1 ± 10.0 (n = 20). Each patient had a mean of 10.1 ± 5.1 cycles of CC prediathermy and 3.6 ± 3.7 cycles of CC postdiathermy. For all CC dosages, and including two spontaneous cycles after diathermy that resulted in two pregnancies, there was a significant difference in the number of responsive cycles postdiathermy (24% versus 66%, P = 0.0003). Conception rates per cycle also were significantly different (3% versus 17%, P = 0.0029). Spontaneous abortion rates per pregnancy were higher prediathermy (4/6 versus 2/12, P insignificant). Conclusions: Oligoovulatory patients who respond poorly to CC therapy may benefit from bilateral ovarian diathermy using the KTP laser. A positive midcycle urinary luteinizing hormone test, sonographic evidence of follicular development to 18mm or greater, a midluteal phase serum progesterone of 10ng/mL or greater, and/or spontaneous menses (only in patients with oligomenorrhea) were considered positive responses to CC.
Infants' Looking at Possible and Impossible Screen Rotations: The Role of Familiarization

The effects of familiarization and age were examined using Baillargeon's rotating screen paradigm. In Condition A, 4-month-olds exposed to 7 180° familiarization trials looked significantly longer at the 180° test events than the 112° test events; there was a familiarity preference. In Condition B, which consisted of 12 instead of 7 180° familiarization trials, the 4-month-olds looked significantly longer at the 112° test events than the 180° test events; there was a novelty preference. In Condition C, which was similar to Condition A except that there were 112° familiarization trials, the infants showed a familiarity preference. Thus, 4-month-olds experiencing 7 familiarization trials exhibited a familiarity preference, and those experiencing 12 familiarization trials showed a novelty preference. In Condition D, 6-month-olds experienced 7 180° familiarization trials; there was no preferential looking to either familiar (180°) test events or novel (112°) test events. Therefore, looking behavior during the test trials was a function of the type of familiarization experience and age and not necessarily an inferred violation of physics.
Ion-Pair Reversed-Phase HPLC Identification of Sugar Nucleotides in Cell Free Extracts of Streptomyces Griseus

Abstract 2,6-Dideoxysugars, biosynthetically derived from glucose through sugar nucleotide intermediates, are important structural components of antibiotics. A HPLC method was developed for the detection of ADPG, UDPG, CDPG, GDPG and/or dTDPG in cell free extracts of Streptomyces griseus. The resolution of these sugar nucleotides and fourteen additional related mono-, di- and triphosphoribo-nucleotides was achieved by gradient elution, ion-pair reversed-phase chromatography (RP-IPC) over an ODS-C18 column. Cell free extracts contained UDPG, GDPG and UDP, thus implicating the two sugar nucleotides in chromomycin-A3 biosynthesis.
Mechanical regulation of the proangiogenic factor CCN1/CYR61 gene requires the combined activities of MRTF-A and CREB-binding protein histone acetyltransferase.

Smooth muscle-rich tissues respond to mechanical overload by an adaptive hypertrophic growth combined with activation of angiogenesis, which potentiates their mechanical overload-bearing capabilities. Neovascularization is associated with mechanical strain-dependent induction of angiogenic factors such as CCN1, an immediate-early gene-encoded matricellular molecule critical for vascular development and repair. Here we have demonstrated that mechanical strain-dependent induction of the CCN1 gene involves signaling cascades through RhoA-mediated actin remodeling and the p38 stress-activated protein kinase (SAPK). Actin signaling controls serum response factor (SRF) activity via SRF interaction with the myocardin-related transcriptional activator (MRTF)-A and tethering to a single CArG box sequence within the CCN1 promoter. Such activity was abolished in mechanically stimulated mouse MRTF-A−/− cells or upon inhibition of CREB-binding protein (CBP) histone acetyltransferase (HAT) either pharmacologically or by siRNAs. Mechanical strain induced CBP-mediated acetylation of histones 3 and 4 at the SRF-binding site and within the CCN1 gene coding region. Inhibition of p38 SAPK reduced CBP HAT activity and its recruitment to the SRF·MRTF-A complex, whereas enforced induction of p38 by upstream activators (e.g. MKK3 and MKK6) enhanced both CBP HAT and CCN1 promoter activities. Similarly, mechanical overload-induced CCN1 gene expression in vivo was associated with nuclear localization of MRTF-A and enrichment of the CCN1 promoter with both MRTF-A and acetylated histone H3. Taken together, these data suggest that signal-controlled activation of SRF, MRTF-A, and CBP provides a novel connection between mechanical stimuli and angiogenic gene expression.
DNA Shape Recognition by the Nucleoid Protein Fis and Its Role in Chromosome Compaction and DNA Recombination

The Fis nucleoid-associated DNA bending protein dynamically binds DNA in a largely sequence-neutral manner. Fis also forms stable complexes to DNA segments that share little sequence conservation. In order to understand how Fis is forming these specific DNA complexes and how it distorts DNA structure upon binding, we have determined X-ray crystal structures of 12 Fis-DNA complexes of variable affinities and stabilities. These structures reveal that Fis selects targets primarily through indirect recognition mechanisms involving the shape of the DNA minor groove and sequence-dependent induced fits over adjacent major groove interfaces to generate overall curvatures of 60-75°. In silico DNA modeling of Fis-bound and unbound DNA molecules suggests a model in which Fis initially selects binding sites based on their intrinsic minor groove shape and then bends the DNA to generate the bound structure. The structures show how binding of Fis leads to DNA compaction, and the location of residues involved in capturing DNA loops implies protein-protein interactions are required for loop stabilization. We have shown that DNA supercoiling and torsional energy associated with the Fis-bound DNA enhancer segment controls the rotational direction and number of Hin subunit translocations that mediate DNA exchange during Hin-catalyzed site-specific DNA inversion. The Fis-DNA structures, together with supporting experimental evidence, enable us to propose a new model for the structure of the Fis-bound Hin invertasome structure.
NONSYMBIOTIC NITROGEN-FIXING MICRO-ORGANISMS IN FOREST AND TUNDRA SOILS *

Soil samples obtained from various forested sites in North Carolina and Washington and from Alaskan tundra were examined for the presence of heterotrophic, nonsymbiotic nitrogen-fixing micro-organisms. Aerobic, nitrogen-fixing micro-organisms were not isolated from any of the soils examined. Estimates of anaerobic nitrogen-fixing bacteria in these soils ranged from 50,000 to 2,000,000/g when a dilution plate technique and a medium supplemented with potato extract was used. However, the isolation of individual colonies from the dilution plates showed that many of these bacteria were unable to fix nitrogen. Soil populations well below 100,000/g were generally indicated by this colony isolation technique. Differentiation of the colonies by size improved the accuracy of the dilution plate estimates somewhat. Dilution tube procedures appeared more suitable for obtaining accurate counts of nitrogen-fixing anaerobes in the soil than the use of dilution plates. The predominant nitrogen-fixing bacterium in most soils was a facultative anaerobe,Bacillus polymyxa. Appreciable numbers of nitrogen-fixing clostridia were also found in several tree nursery soils but were seldom isolated from forest and tundra samples. The clostridia isolated were classified asClostridium butyricum andC. pasteurianum. Variations in the fermentation patterns of these bacteria occurred when the nitrogen supply of the medium was altered. TheC. butyricum isolates were all from forest soils while all except one of theC. pasteuranium isolates were from tundra soils.
Developing a new advanced microcontrollers course as a part of embedded systems curriculum

This paper presents our experiences in developing a new advanced microcontrollers course within the Department of Electrical Engineering and Computing Systems at the University of Cincinnati (UC). This course was developed and offered for the first time in Spring 2013 to undergraduate seniors and first-year graduate students in electrical and computer engineering. It is also open to interested students in other relevant science and engineering programs. The course aims at providing advanced skills in designing and developing microcontroller-based embedded systems. It adopts an instruction model that integrates active learning techniques with in-class lectures and laboratory projects. The paper elaborates on the course structure and schedule, pedagogical techniques used in the course, and student feedback results. It also explains how this course fits in to the existing embedded systems curriculum at UC.
A Decade of Ecosystems

Ten years ago, Ecosystems was introduced as a ‘‘substrate for primary succession of the discipline‘‘ (Carpenter and Turner 1998). We envisioned Ecosystems as an arena for new ways of thinking and new kinds of progress in ecosystem science. We suggested four frontiers that seemed particularly important at that time. ‘‘People and ecosystems‘‘ addressed the study of social-ecological systems, including pressing issues of sustainability. ‘‘Spatial dynamics and scale shifts‘‘ was concerned with expanding the range of spatial scales considered by ecosystem scientists and improving conceptual and empirical tools for understanding spatially structured processes. ‘‘Cross-disciplinary linkages‘‘ have frequently stimulated progress in ecosystem science, and we encouraged contributors to Ecosystems to embrace linkages among the subdisciplines of ecology, among natural sciences, and across social and natural sciences. ‘‘Temporal scale interactions‘‘ involved feedbacks of slow and fast variables, disturbance regimes, thresholds and ecosystem surprises. The first year of Ecosystems showed reasonable balance among the four frontiers (Turner and Carpenter 1999a, b, c). Spatial dynamics and scale shifts were best represented of the four frontiers. Vigorous hybrids of landscape and traditional ecosystem ecology continue to be a major growth area for science that is strongly represented in the pages of Ecosystems. The journal‘s first year coincided with publication of an important assessment of ecosystem science from the seventh Cary Conference (Pace and Groffman 1998a, b). That volume (Pace and Groffman 1998a) stressed the need for greater integration among the subdisciplines of ecology, and of ecology with other disciplines, to invigorate the science and address the ‘‘rising tide of humanaccelerated ecological change‘‘ (Pace and Groffman 1998b). We were pleased by the high frequency of synthetic papers in the first volume of Ecosystems (Turner and Carpenter 1999a, b, c).
Rodent genetic models of Huntington disease

Huntington disease (HD) is a dominantly inherited human neurodegenerative disorder characterized by motor deficits, cognitive impairment, and psychiatric symptoms leading to inexorable decline and death. Since the identification of the huntingtin gene and the characteristic expanded CAG repeat/polyglutamine mutation, multiple murine genetic models and one rat genetic model have been generated. These models fall into two general categories: transgenic models with ectopic expression of the characteristic expanded CAG codon mutation, and knock-in models with expression of mutant huntingtin under control of endogenous regulatory elements. Rodent genetic models are valuable tools for studying mechanisms of pathogenesis in HD and for preclinical evaluation of possible therapies. In this mini-review, we provide a concise comparative summary of rodent genetic models of HD.
Incorporation of selenium-75-labeled rat plasma proteins into rat liver ribosomes.

Abstract A cell-free system with washed rat liver ribosomes was used to study the metabolic pathway of the incorporation of selenium into rat liver ribosomes. Time-course incorporation of 75 Se-labeled rat plasma proteins ( 75 Se-PP) indicated that 27% of the 75 Se-PP was incorporated into ribosomes in 1 hour. The incorporation of 75 Se-PP into ribosomes is dependent upon ATP but not cell sap. Potassium cyanide (10 −3 m ) reduced the incorporation of 75 Se-PP into ribosomes by about 60%, but 2,4-dinitrophenol, oligomycin, and puromycin had no effect. Extraction of 75 Se-PP and 75 Se-labeled ribosomes with hot alcohol and with trichloroacetic acid suggest that 75 Se-labeled peptides were not exchanged or transferred between plasma proteins and ribosomes. Results support the concept that large aggregates of selenium-containing protein(s) or entire proteins are transferred in vitro to rat liver ribosomes.
Increased H+ efflux is sufficient to induce dysplasia and necessary for viability with oncogene expression

Intracellular pH (pHi) dynamics is increasingly recognized as an important regulator of a range of normal and pathological cell behaviors. Notably, increased pHi is now acknowledged as a conserved characteristic of cancers and in cell models is confirmed to increase proliferation and migration as well as limit apoptosis. However, the significance of increased pHi for cancer in vivo remains unresolved. Using Drosophila melanogaster, we show that increased pHi is sufficient to induce dysplasia in the absence of other transforming cues and potentiates growth and invasion with oncogenic Ras. Using a genetically encoded biosensor we also confirm increased pHi in situ. Moreover, in Drosophila models and clonal human mammary cells we show that limiting H(+) efflux with oncogenic Raf or Ras induces acidosis and synthetic lethality. Further, we show lethality in invasive primary tumor cell lines with inhibiting H(+) efflux. Synthetic lethality with reduced H(+) efflux and activated oncogene expression could be exploited therapeutically to restrain cancer progression while limiting off-target effects.
A Versatile Internet-Accessible Electronics Workbench with Troubleshooting Capabilities

The MIT iLab Project was established to expand the range of laboratory experiences available to students in science and engineering education. iLabs are online laboratories that enable students to conduct real experiments remotely. Recently, the iLab Project has focused on building remote laboratories around the NI-ELVIS platform, an all-in-one electronics workbench. This paper will detail our recent efforts in expanding the capabilities of ELVIS-based iLabs by enabling students to test and debug digital and analog circuits. This work will enable students to perform remote experiments characterizing digital logic elements. By merging switching capabilities with the Digital Multimeter available on the ELVIS, students will have the ability to examine and troubleshoot circuits. These added capabilities will provide educators and students with unparalleled flexibility and significantly enrich the remote laboratory experience.
Development of teaching tool for building construction

This paper includes a review of past attempts to use models as a teaching tool. It also describes the development of the Building Systems Modeling, Assembly, Research, and Teaching Tool (BSMARTT) at the College of Architecture and Urban Studies of Virginia Polytechnic Institute and State University (Virginia Tech). BSMARTT is a set of kits of small-scale building components for learning different processes and methods of construction. Different model materials are used such that the model kits and their components represent most of the common and important materials in today's construction environment. Each kit is accompanied by computer software which guides the user through the process of assembly and construction. With the aid of a modeling application, the computer software visually simulates the process of building construction and assembly, taking the user through putting a building together step by step. It can also focus on critical elements in the building system and help the student understand s...
Electron microscopy of mitochondrial changes in Saccharomyces.

Lamellated mitchondria which have not been observed previously in yeasts were observed in thin section by electron microscopy after fixation with 2% aqueous potassium permanganate following treatment with uranyl acetate and embedding in methacrylate mixture. The lamellated mitohondria occurred in old cultures held under partially anaerobic conditions and appeared to result from changes in the inner membranes of certain mitochondria.
NO: an inhibitor of cell death

Nitric oxide (NO) or related molecules of both endogenous and exogenous origin inhibit programmed cell death in a variety of cells and tissues. This general protective function is largely independent of the apoptotic stimulus. S-nitrosylation of the catalytic-site cysteine of caspases is a well-established and possibly widespread mechanism of enzyme inhibition that protects from cell death. However, NO may inhibit apoptosis by additional mechanisms. The physiological and pathological significance of NO's anti-apoptotic activity remains to be determined in most cases.
Scatter Considerations in Fan Beam Computerized Tomographic Systems

In fan beam computerized tomography, a crosschannel noise problem arises due to the scattering of photons from one path into another. This paper describes the effect of these scattered photons on the reconstructed image and gives an estimate of the quantities of scatter which are acceptable without serious degradation of the reconstruction.
Effects of task duration on sensitivity to sleep deprivation using the multi-attribute task battery

Several factors affect the sensitivity to sleep deprivation in the performance of computerized tests. Two of these are task complexity and duration. Complexity can improve sensitivity by increasing the demands required to complete the task, but it can also decrease sensitivity by improving the subject’s motivation. The effects of task duration are more predictable in that longer tests generally are more susceptible to deprivation effects than shorter ones. The impact of task duration on an interesting, but complex, aviation simulation was examined here. By breaking down data from 30-min multi-attribute task battery administrations into the first, second, and third 10 min of performance, it was shown that tests shorter than 30 min underestimate the impact of sleep loss on performance. This was especially evident in measures of time-out and tracking errors.
Climatic determinants of irrigated rice performance in the Sahel — III. Characterizing environments by simulating crop phenology

Abstract Agricultural development programs in most countries of the Sahel seek to increase the intensity of irrigated rice production. Variable crop duration and temperature stresses, however, limit yields and calendrial options. In an effort to characterize climatic constraints to rice double-cropping in the region, a field-based model simulating flowering was combined with models predicting maturity and chilling- and heat-induced spikelet sterility. Simulations were performed for key sowing dates, 38 sites and three genotypes based on 10–33 years of weather records. Sowing between mid-September and mid-November was associated with near-total spikelet sterility due to chilling in all Sahelian environments. Crop duration was longest in November, increasing by 5 days per degree latitude in the continental Sahel. Greatest annual variation in duration was observed in the coastal west and extreme north of the Sahel. Climatic gradients along the courses of the Senegal and Niger rivers were associated with different annual patterns of duration and sterility. Based on the genotypes available to farmers, local rice-rice cropping calendars left little room for alternative calendars. Achieving a greater flexibility for cropping calendars would require the introduction of alternative short-duration varieties. The model permits the zonation of the Sahel in terms of calendrial options and varietal requirements. For a greater spatial resolution of such studies in the future, however, the pooling and digitalization of more weather data is recommended.
Reactions catalyzed by tetrahydrobiopterin-free nitric oxide synthase.

Murine macrophage nitric oxide synthase (NOS) was expressed in E. coli and purified in the presence (holoNOS) or absence (H4B-free NOS) of (6R)-tetrahydro-l-biopterin (H4B). Isolation of active enz...
UNIVERSITY TEACHERS IN SENIOR COMMUNITY AGENCIES

University teachers in many disciplines are encouraged to use their academic specialization and teaching skills in agencies that work with older persons. Such community involvement benefits the seniors, the agencies, and the professors who volunteer. In comparison with the college situation, volunteer teachers will find a great degree of flexibility in this environment. Specific rewards for the teachers include demonstration of public service, personal satisfaction derived from teaching an appreciative audience, the opportunity to learn, the acquisition of lecture material for on campus courses, the establishment of a network accessible to teachers and students, and the development of potential research sites. An example of a sociologist and a Foster Grandparent Program is presented as an illustration.