cssi/SciSciGPT-SciSciNet huggingface dataset:
The hydrocarbon-degrading marine bacterium Cobetia sp. strain MM1IDA2H-1 produces a biosurfactant that interferes with quorum sensing of fish pathogens by signal hijacking

Biosurfactants are produced by hydrocarbon-degrading marine bacteria in response to the presence of water-insoluble hydrocarbons. This is believed to facilitate the uptake of hydrocarbons by bacteria. However, these diffusible amphiphilic surface-active molecules are involved in several other biological functions such as microbial competition and intra- or inter-species communication. We report the isolation and characterization of a marine bacterial strain identified as Cobetia sp. MM1IDA2H-1, which can grow using the sulfur-containing heterocyclic aromatic hydrocarbon dibenzothiophene (DBT). As with DBT, when the isolated strain is grown in the presence of a microbial competitor, it produces a biosurfactant. Because the obtained biosurfactant was formed by hydroxy fatty acids and extracellular lipidic structures were observed during bacterial growth, we investigated whether the biosurfactant at its critical micelle concentration can interfere with bacterial communication systems such as quorum sensing. We focused on Aeromonas salmonicida subsp. salmonicida, a fish pathogen whose virulence relies on quorum sensing signals. Using biosensors for quorum sensing based on Chromobacterium violaceum and Vibrio anguillarum, we showed that when the purified biosurfactant was mixed with N-acyl homoserine lactones produced by A. salmonicida, quorum sensing was inhibited, although bacterial growth was not affected. In addition, the transcriptional activities of A. salmonicida virulence genes that are controlled by quorum sensing were repressed by both the purified biosurfactant and the growth in the presence of Cobetia sp. MM1IDA2H-1. We propose that the biosurfactant, or the lipid structures interact with the N-acyl homoserine lactones, inhibiting their function. This could be used as a strategy to interfere with the quorum sensing systems of bacterial fish pathogens, which represents an attractive alternative to classical antimicrobial therapies in fish aquaculture.
Mesomorphic Transition Metal N2O2 Chelates

Abstract The first class of transition metal N2O2 liquid crystals are reported. They are synthesized as the alkyl ethers of N,N'-bis(5-hydroxysalicylidene) ethylene diamine Mt|| complexes (Salen-Mt-n) containing either Cu|| or Ni||. Both series were prepared with pentyl through nonyl alkane units. All complexes except Salen-Cu-5 exhibit liquid crystallinity. Decomposition controls the thermal behavior in the Salen-Cu-n complex series with degradation occurring several degrees above the clearing point. Smectic mesomorphism is found in all liquid crystalline chelates. The differences in the thermal characteristics between Salen-Cu-n and Salen-Ni-n chelates is attributed to the different electronic structures of the chelated metals. This behavior exemplifies the influence of the metal upon mesomorphic properties.
Adsorption of proteins from artificial tear solutions to contact lens materials.

A series of polymers and copolymers of 2-hydroxyethyl methacrylate (HEMA) and methyl methacrylate (MMA) were synthesized in order to find surfaces that would adsorb minimal amounts of protein. The adsorption of albumin, lysozyme and immunoglobulin G from a three-way mixture of these proteins in isotonic buffered saline to the polymers was measured using /sup 125/I-labeled proteins. Apparently high protein uptake on copolymers rich in HEMA was found to be due to sorption of unbound /sup 125/I by the polymers. /sup 125/I sorption by the polymers was minimized by dialysis of the protein solution to remove unbound /sup 125/I iodide and inclusion of 0.01 M sodium iodide to block uptake of residual /sup 125/I iodide. Using these improved protocols, minimal total protein uptake was observed on copolymers containing 50% or more HEMA. The majority of adsorbed protein on all p(MMA-HEMA) polymers was albumin. Total protein uptake was greatest on pMMA. Commercial contact lenses composed of copolymers of HEMA and N-vinyl pyrrolidone (NVP) or acrylamide (AAm) adsorbed small amounts of all proteins whereas copolymers of methacrylic acid (MAAc) and HEMA adsorbed much larger quantities of lysozyme. These results indicate that protein uptake by contact lens materials varies greatly with polymer composition. Artifactuallymore » high adsorption can occur if precautions are not taken to prevent uptake of unbound /sup 125/I.« less
Racial variation in cancer care: a case study of prostate cancer.

There is convincing documentation of racial variation in the incidence and mortality of many cancers, particularly cancers of the breast, colon, lung, and prostate.[1,2] Racial differences are also reported in the clinical management of these cancers.[3,4] This phenomenon, that is, racial variations in the occurrence and treatment of disease, is not unique to cancers. Racial differences are found in incidence, patterns of care, and patient outcomes for many other diseases and conditions, e.g., cardiovascular and cerebrovascular disease.[5]–[8] Efforts to further document its existence would seem to be unwarranted.
Software integration in design of flexible manufacturing systems

A method for integration of classification, computer-aided design, process planning and scheduling, and control modules in the design of flexible manufacturing systems is (FMSs) presented. The requirements for cells are deduced, and an FMS integrated software is proposed with the help of a database design. A knowledge-based rough classification and coding system has been developed for coding similar parts, and an expert code convertor was developed to translate non-Opitz code into Opitz code. A product data system is designed using computer-aided programming for designing a family of similar parts. A process planning module is interfaced with CAD and other systems to generate a suitable process plan. A set of rules is suggested to determine the optimum scheduling procedure for machining operations. An FMS control algorithm using Petri net controllers is presented. Software integration of the FMS systems and factory floor practices is discussed. >
Enzymatic Variants of Influenza Virus. I. Isolation and Characterization of Slowly Reacting Enzymatic Variants of Influenza B Virus.

Slowly reacting enzymatic variants of the Lee strain of influenza B virus were isolated by the serial application of a technique which concentrated the fraction of the virus population obtained by slow elution followed by passage of this fraction at high dilution in chicken embryos. The variants were stable upon serial passage in chicken embryos and did not differ significantly from the parent virus in any of the characteristics tested other than those relating to the virus enzyme. Enzymatically, the variants had a much slower rate of activity on chicken mucoproteins than the parent virus. Their activity was greater at 25°C. than at 37°C. and was much enhanced by calcium ions and depressed by a calcium chelating agent. The enzyme of the variant virus was more labile to heat than that of the parent virus although their hemagglutinins were equally stable. It was estimated that the variants comprised less than 3 per cent of the original population of the Lee strain of influenza B virus particles.
A linear programming model of housing market equilibrium

Abstract This paper reviews Wheaton's assertion that the Herbert-Stevens Linear Programming Model produces solutions which do not meet Alonso's criteria for market equilibrium. It demonstrates that, although Wheaton's criticism is valid in general, under certain conditions an alternative specification of the objective function coefficients and the dual variables in the linear program produces a model whose solutions satisfy Alonso's criteria. Finally, this paper shows that the NBER model is an application in which a linear programming problem computes market equilibria.
Cell-Seeding Techniques in Vascular Tissue Engineering

Previous studies have demonstrated the benefits of cell seeding in the construction of tissue-engineered vascular grafts (TEVG). However, seeding methods are diverse and no method is clearly superior in either promoting seeding efficiency or improving long-term graft function. As we head into an era during which a variety of different TEVG are under investigation in clinical trials around the world, it is important to consider the regulatory issues surrounding the translation of these technologies. In this review, we summarize important advances in the field of vascular tissue engineering, with particular attention on cell-seeding techniques for TEVG development and special emphasis placed on regulatory issues concerning the clinical translation of these various methods.
Purification of the Saccharomyces cerevisiae cleavage/polyadenylation factor I. Separation into two components that are required for both cleavage and polyadenylation of mRNA 3' ends.

Abstract The cleavage/polyadenylation factor I (CF I) is one of four factors required for mRNA 3′ end formation in the yeast Saccharomyces cerevisiae. Here we describe the purification of CF I and its separation into two components, CF IA and CF IB. Both components are needed to reconstitute CF I activity in cleavage and poly(A) addition. CF IA consists of a complex of four polypeptides of 76, 70, 50, and 38 kDa, and CF IB is a single 73-kDa polypeptide. The 76- and 38-kDa subunits of CF IA correspond to the previously identified RNA14 and RNA15 proteins. The RNA14 protein, but not the 70- or 50-kDa proteins, coimmunoprecipitates with the RNA15 protein, indicating that RNA14 and RNA15 proteins exist in a tight complex. RNA15 is the only subunit of CF I that can be cross-linked to pre-mRNA.
Protein matching with custom neural network objective functions

This 2004 KDD Cup presents a perfect case where the usual neural network objective functions do not apply. While the contest problem consisted of 4 different entries with 4 different objective functions, this paper will focus on the solution optimizing GRMSE (Grouped Root Mean Squared Error). It will be shown that the more typical objective functions (including RMSE) cannot be as effective at meeting this criteria. While this objective function may be specific to this problem, and the reader may never see this exact function again in his/her lifetime, the idea behind this paper is applicable in many situations. Too often neural networks are used to minimize SSE (sum of the squares of the errors) or Cross Entropy, when the true measure of success for the model may require a small coding change to the Neural Network objective function. It is shown in this paper that a few small coding changes can make a big difference on a model's performance.
Induction of cardiac myogenic lineage development differs between mesenchymal and satellite cells and is accelerated by bone morphogenetic protein-4

Our aim was to further elucidate the cardiac lineage development of bone marrow-derived mesenchymal stem cells (MSC) and to identify cells which had the potential for cardiac myogenic differentiation when compared to skeletal muscle satellite (Sk-sat) myogenesis. Unlike Sk-sat, MSC expressed the early cardiac markers Nkx2.5 and GATA4. Their expression was significantly increased by culturing MSC with Bone Morphogenetic Protein 4 (BMP4). Enhanced cardiac myogenic lineage differentiation and loss of stem cell characteristics induced by BMP4 were further confirmed by flow cytometry of cells stained for Nkx2.5 and Sca-1 expression. MSC also expressed skeletal genes (MyoG, ssTnI, Sk-Act) early in culture but their expression was suppressed when BMP4 was added from day 0 to day 6 (p<0.05). BMP4 treated MSC also exhibited a 6-fold increase in cTnI expression by day 12 in culture. The average MSC action potential time duration at 90% (APD90) was 32.3±4ms, with some cells exhibiting action potentials closer to Sk-sat APD90 of 13.7±0.9ms. After treatment with BMP4, MSC significantly increased their APD90 to 54.4±7.6ms, shifting from the shorter skeletal-like signature, towards a longer action potential duration more characteristic of a cardiomyocyte signature. Our results show that MSC and Sk-sat exhibit similarities in myogenic lineage development early in culture but that BMP4 clearly enhances cardiac myogenic development, suppresses skeletal myogenesis, and leads to loss of "stemness" in MSC. These findings provide novel information regarding the use of BMP4 to accelerate cardiac myogenic development in harvested MSC and further support the use of MSC in cardiac regenerative therapy.
The Effect of Context on Moral Intensity of Ethical Issues: Revising Jones's Issue-Contingent Model

Jones's (1991) issue-contingent model of ethical decision making posits that six dimensions of moral intensity influence decision makers' recognition of an issue as a moral problem and subsequent behavior. He notes that "organizational settings present special challenges to moral agents" (1991, p. 390) and that organizational factors affect "moral decision making and behavior at two points: establishing moral intent and engaging in moral behavior" (1991, p. 391). This model, however, minimizes both the impact of organizational setting and organizational factors on these experiences of ethical issues. In this theory, context is modeled as affecting the moral intent and behavior of the actor rather than directly affecting the issue's moral intensity. Here we look specifically at the effect of context on the moral intensity of ethical issues through a phenomenological study. Our results indicate that in certain environments, context may be critical in affecting the moral intensity of ethical issues. Thus, researchers should consider it more fully when assessing these issues' moral intensity.
Modeling the benefits of advanced traveler information systems in corridors with incidents

Abstract This paper concerns the benefits from Advanced Traveler Information Systems (ATIS) in corridors under incident conditions. A deterministic queueing model is developed and applied to an idealized corridor composed of two routes. A user optimal strategy is implemented to disseminate real-time traffic information to vehicles equipped with ATIS as they approach the incident bottleneck. The sensitivity of route guidance benefits to relevant parameters such as the fraction of vehicles guided with ATIS is analyzed. The findings show that a few cases of queue evolution result when ATIS is used under incident conditions. Both the proportion of guided traffic and the incident duration play an important role in determining which case results. When an incident occurs, ATIS will divert all equipped vehicles to the alternate route until equilibrium is achieved. Equilibrium is achieved only if a sufficient number of guided vehicles comply with diversion instructions. Equilibrium is maintained by reducing the rate of diversion from one route to the other. The implication is that during equilibrium some guided travelers will be diverted to the alternate route, while others will remain on the route where the incident has occurred. It is found that the benefits to guided traffic decrease when the proportion of guided traffic exceeds a critical value that causes a queue on the alternate route. The system benefits also level off once the critical value is exceeded. Therefore, if the system management has the choice, there is no need to equip more than the critical fraction of vehicles with ATIS. There is a need to develop a methodology that can find practical estimates of the critical fraction for use in large-scale simulations of real-life networks.
Evasion of P-gp mediated cellular efflux and permeability enhancement of HIV-protease inhibitor saquinavir by prodrug modification.

Abstract P-glycoprotein (P-gp) is an efflux pump responsible for limiting oral bioavailability, tissue penetration and increasing metabolism of the HIV protease inhibitor saquinavir (SQV). The objective of this study is to investigate whether prodrug derivatization of SQV to novel dipeptide prodrugs Val–Val–saquinavir (Val–Val–SQV) and Gly–Val–saquinavir (Gly–Val–SQV) targeting peptide transporters can enhance cellular permeability of saquinavir and modulate P-gp mediated efflux. Uptake and transport studies were conducted employing MDCKII-MDRI cell line at 37 °C for 10 min and 3 h, respectively. Uptake of [3H]ritonavir and [3H]erythromycin, utilized as model P-gp substrates, was carried out in the presence of inhibitory concentration of SQV and its peptide prodrugs. Bidirectional transport studies were conducted on MDCKII-MDR1 cells grown over membrane inserts. Uptake of [3H]erythromycin by MDCKII-MDR1 cells exhibited a four-fold increase in the presence of 75 μM SQV. However, equimolar concentrations of Val–Val–SQV and Gly–Val–SQV showed only 2.5-fold increase in [3H]erythromycin uptake. Concentration dependent inhibition of [3H]glycylsarcosine (Gly-Sar), a model peptide transporter substrate, was observed in the presence of SQV prodrugs. Transepithelial transport studies of Val–Val–SQV and Gly–Val–SQV exhibited an enhanced absorptive flux and reduced secretory flux relative to studies employing SQV. These results are very likely due to decreased efflux of SQV dipeptide prodrugs by P-gp. Peptide prodrug derivatization constitutes an exciting strategy to improve intestinal absorption and oral bioavailability of SQV.
An excel based Semantic email system

Semantic Email is a type of Semantic Web application, which deals with the understanding of emails received, and performing corresponding actions according to the schema specified in the Semantic Email system.In this paper, the Semantic Email is implemented with a restriction of using excel sheets as a mode of communication. The current Semantic Email project could be reengineered to support heterogeneous semantic actions based on the action plan. The Semantic Email project can be enhanced providing a web interface, apart from the email system currently used for communication. The clients can directly use the web page, corresponding to the schema rather than sending an email.
Suppression of populations of tobacco budworms caged with sterile females.

Field-cage releases of adult female Heliothis virescens (F.) reared on larval diets containing reserpine and irradiated as pupae with 20 krad of gamma irradiation reduced the F1 larval generation ca. 70% from that of the check when the ratio of releases was 9:1 irradiated to unirradiated. Releases of both sexes of irradiated insects at the same ratios reduced F1 larval populations ca. 39%. An additional reduction was obtained when irradiated females were released into populations of F1 moths. The fecundity of P1 and F1 moths was reduced 18 and 28%, respectively, when irradiated females were released once and 33 and 42% when they were released twice.
The subconstituent algebra of a Latin square

It is well-known that one may construct a 4-class association scheme on the positions of a Latin square, where the relations are the identity, being in the same row, being in the same column, having the same entry, and everything else. We describe the subconstituent (Terwilliger) algebras of such an association scheme.
A practical guide to defining high-risk myeloma for clinical trials, patient counseling and choice of therapy

Clinical outcomes for multiple myeloma (MM) are highly heterogeneous and it is now clear that pivotal genetic events are the primary harbingers of such variation. These findings have broad implications for counseling, choice of therapy and the design and interpretation of clinical investigation. Indeed, as in acute leukemias and non-hodgkins lymphoma, we believe it is no longer acceptable to consider MM a single disease entity. As such, the accurate diagnosis of MM subtypes and the adoption of common criteria for the identification and stratification of MM patients has become critical. Herein, we provide a consensus high-risk definition and offer practical guidelines for the adoption of routine diagnostic testing. Although acknowledging that more refined classifications will continue to be developed, we propose that the definition of high-risk disease (any of the t(4;14), t(14;16), t(14;20), deletion 17q13, aneuploidy or deletion chromosome 13 by metaphase cytogenetics, or plasma cell labeling index >3.0) be adopted. This classification will identify most of the 25% of MM patients for whom current therapies are inadequate and for whom investigational regimens should be vigorously pursued. Conversely, the 75% of patients remaining have more favorable outcomes using existing - albeit non-curative - therapeutic options.
IRF-4 functions as a tumor suppressor in early B-cell development

Interferon regulatory factor-4 (IRF-4) is a hematopoietic cell–restricted transcription factor important for hematopoietic development and immune response regulation. It was also originally identified as the product of a proto-oncogene involved in chromosomal translocations in multiple myeloma. In contrast to its oncogenic function in late stages of B lymphopoiesis, expression of IRF-4 is down-regulated in certain myeloid and early B-lymphoid malignancies. In this study, we found that the IRF-4 protein levels are increased in lymphoblastic cells transformed by the BCR/ABL oncogene in response to BCR/ABL tyrosine kinase inhibitor imatinib. We further found that IRF-4 deficiency enhances BCR/ABL transformation of B-lymphoid progenitors in vitro and accelerates disease progression of BCR/ABL-induced acute B-lymphoblastic leukemia (B-ALL) in mice, whereas forced expression of IRF-4 potently suppresses BCR/ABL transformation of B-lymphoid progenitors in vitro and BCR/ABL-induced B-ALL in vivo. Further analysis showed that IRF-4 inhibits growth of BCR/ABL+ B lymphoblasts primarily through negative regulation of cell-cycle progression. These results demonstrate that IRF-4 functions as tumor suppressor in early B-cell development and may allow elucidation of new molecular pathways significant to the lymphoid leukemogenesis by BCR/ABL. The context dependent roles of IRF-4 in oncogenesis should be an important consideration in developing cancer therapies targeting IRF-4.
Discussion on “Two-Stage Procedures for High-Dimensional Data” by Makoto Aoshima and Kazuyoshi Yata

Abstract I have noted that the asymptotics do not appear to kick in as early as I might have expected to see for some of the selected problems. I hope that Professors Aoshima and Yata can shed some light on this to facilitate practical implementation.
Two ACEs and a heart.

Cardiovascular diseases are some of the biggest killers in the developed world. The discovery of a new enzyme that affects cardiac function might provide fresh insight into heart disease.
Symptom expression in pain-predominant functional bowel syndrome: is visceral hyperalgesia the whole truth?

Symptom expression in pain-predominant functional bowel syndrome: is visceral hyperalgesia the whole truth?
Choice of antibiotic for empirical therapy of acute cystitis in a setting of high antimicrobial resistance.

Background: A high prevalence of antimicrobial resistance among urinary isolates in the Garhwal region of Uttaranchal. Aims: To identify the most appropriate antibiotic for empirical treatment of community-acquired acute cystitis on the basis of local antimicrobial sensitivity profile. Settings and Design: A prospective clinico-microbiological study including all clinically diagnosed patients with community acquired acute cystitis attending a tertiary care teaching hospital over a period of three years. Methods and Material: Clean-catch midstream urine specimens, from 524 non-pregnant women with community-acquired acute cystitis, were subjected to semi-quantitative culture and antibiotic susceptibility by the Kirby- Bauer disc diffusion method. A survey was also conducted on 30 randomly selected local practitioners, to know the prevalent prescribing habits in this condition. Statistical Analysis: The difference between the susceptibility rates of E. coli isolates to Nitrofurantoin and the other commonly prescribed antibiotics was analysed by applying the z test for proportion. Results: 354 (67.5%) specimens yielded significant growth of E. coli. >35% of the urinary E.coli isolates were resistant to the fluoroquinolones, which were found to be the most commonly used empirical antibiotics in acute cystitis. Resistance was minimum against Nitrofurantoin (9.3%, 33) and Amikacin (11.0%,39). >80% of the fluoroquinolone-resistant strains were found to be sensitive to Nitrofurantoin. Conclusion: The best in vitro susceptibility profile in our study has been shown by Nitrofurantoin and a significantly high proportion of the urinary E. coli isolates have already developed resistance to the currently prescribed empirical antibiotics, viz. the fluoroquinolones. In view of these in vitro susceptibility patterns, a transition in empirical therapy appears imminent.
Chromate reductase activity of Enterobacter aerogenes is induced by nitrite

A chromate resistant mutant of Enterobacter aerogenes manifested its chromate resistance only under aerobic conditions. Both parent and mutant showed substantial levels of anaerobic chromate reductase activity when grown on glycerol plus fumarate. The chromate reductase was further induced by growth in the presence of nitrite but was repressed by nitrate. The chromate reductase activity paralleled that of the formate-linked nitrite reductase. There was no significant difference in chromate reductase levels between the parent and its chromate resistant mutant, indicating that this enzyme activity is not, in fact responsible for chromate resistance as was suggested previously by others.
Poly(3-decylthiophene) radical anions and cations in solution: single and multiple polarons and their delocalization lengths in conjugated polymers.

Optical absorption spectra of anions and cations of poly(3-decylthiophene) (P3DT) in solution were identified as single polarons. Pulse radiolysis of P3DT in THF determined the spatial extent of one negative polaron to be ∼11.5 thiophene units by observing transient absorption of P3DT–• radical ions, which are prinicpally free ions, at 850 nm with e = (7.25 ± 0.47) × 104 M–1 cm–1 and bleaching of the neutral absorption band at 450 nm. P3DT–• was formed in a combination of diffusive reactions and fast “step” processes. Similarly, a positive polaron of P3DT was estimated to delocalize over ∼8.7 thiophene units by pulse radiolysis in chloroform. Chemical reduction by sodium and oxidation by FeCl3 injected multiple charges into a single P3DT chain while showing absorption spectra in the early stages of reaction resembling those observed by pulse radiolysis. The results indicated that multiple polarons exist in a single chain of P3DT before coalescing into bipolarons or transforming into other forms of polaron.
Communication: conical intersections between vibrationally adiabatic surfaces in methanol.

A set of seven conical intersections (CI’s) in methanol between vibrationally adiabatic surfaces is reported. The intersecting surfaces represent the energies of the two asymmetric CH stretch vibrations regarded as adiabatic functions of the torsion and COH bend angles. The ab initio data are well described by an extended Zwanziger and Grant (E ⊗ e) model [J. W. Zwanziger and E. R. Grant, J. Chem. Phys. 87, 2954 (1987)] that might also be regarded as an extension of the XHL model [L.-H. Xu, J. T. Hougen, and R. M. Lees, J. Mol. Spectrosc. 293–294, 38 (2013)]. The CI's illuminate the role of geometric phase in methanol. More generally, they suggest the importance of energy transfer processes localized near the CI’s.
Building Utopias: Successes and Failures

Four long-lasting and prosperous utopian enterprises are compared to the American communes of the 1960's in an effort to detect what facors accounted for their success. In general, the successful utopian experiments shared certain traits that were absent in the American communes. They selectively recruited their members, submitted them to an initial socialization process, imbued an ideology of sacrifice and brotherhood, worked within a democratic framework, legitimated a system of authority, possessed capital, invested in human capital, encouraged worker ownership, recognized their interdependence, used flexible economic policies, asked their members to renounce the outside world, and created a sense of communion and transcendence.
Lessons on Quality Control in Large Scale Imaging Trials: the Multi-Ethnic Study of Atherosclerosis (MESA)

The Multi-Ethnic Study of Atherosclerosis (MESA), initiated in July 2000, is a six-center longitudinal population-based study that included 6,814 men and women at baseline study. Cardiac MRI was part of the study procedures, representing the first large-scale application of cardiac MRI in a multi-center and multi-ethnic population study in the USA. To date, this is the largest ever MRI study. Such effort would come with a great potential for variability due to the number of professionals involved; therefore, an intensive quality control process was implemented since the very beginning. A workflow for process control was used to match image protocols in different types of MRI scanners, transfer images to the reading center, train technicians, and implement image quality scorecards. This article reviews the influence of research management for quality control and work standardization processes in cardiac magnetic MRI results at the 10th year of follow-up in MESA.
Careers perspective interview: Norka Ruiz Bravo.

I toyed briefly with other things, including writing, which I enjoy, but the opportunity for research administration at NIH came up before I had a chance to explore other potential careers seriously. I am confident that I made the right choice for me.
Revisiting Readability: A Unified Framework for Predicting Text Quality

We combine lexical, syntactic, and discourse features to produce a highly predictive model of human readers' judgments of text readability. This is the first study to take into account such a variety of linguistic factors and the first to empirically demonstrate that discourse relations are strongly associated with the perceived quality of text. We show that various surface metrics generally expected to be related to readability are not very good predictors of readability judgments in our Wall Street Journal corpus. We also establish that readability predictors behave differently depending on the task: predicting text readability or ranking the readability. Our experiments indicate that discourse relations are the one class of features that exhibits robustness across these two tasks.
On the Feasibility of a Timely Transition to a More Sustainable Energy Future

The paper uses the framework of the IPAT equation, as applied to CO2 emission, to decompose the various driving forces in the global energy use. Data from recent history are superimposed on projections of SRES IPCC scenarios to determine if enough sustainable capacity can be built to prevent irreversible ecological deterioration. The conclusion from the analysis is that, in agreement with the IPCC 4th report, until about 2030 there are no large differences between a sustainable scenario and the one that resembles “business as usual”. The sharp divergence that follows stems from different estimates in population growth and in the percentage of use of fossil fuels in the total energy mix. Decomposition of alternative energy options indicate that the rate of increase of alternatives such as hydroelectric and nuclear start with a relatively high base but a growth rate too short for major contribution to a timely replacement of fossil fuels while wind and solar starts from a much lower base but rate of growth, if maintained, that can satisfy a timely replacement.
Fabrication and Characterization of a Membrane Based Hair Cell Sensor That Features Soft Hydrogel Materials

One of the most common sensory structures in nature is the hair cell. Examples of hair cells include the inner and outer hair cells in the inner ears of vertebrates, external sensory hairs on the legs of spiders, and neuromasts found along the lateral lines of fish. Recent work by Sarles and Leo demonstrated that self-assembly methods could be used to construct a membrane-based hair cell that responds to a physical disturbance of the hair. An artificial cell membrane (or lipid bilayer) formed at the interface of two lipid-encased hydrogel volumes, serves as the transduction element in the device. In this study, a revised sensor embodiment is presented in which the hair is fixed at its base by the encapsulating polymeric substrate. In addition, a highly elastic, photo-polymerizable aqueous gel (PEGDA, 6000g/mole) is used to further increase the resiliency of the hair and to provide a compliant cushion for the bilayer. These changes yield a considerably more durable hair cell sensor. We perform a series of experimental tests to characterize the transduction element (i.e. the bilayer) and the sensing current produced by free vibration of the hair, and we study the directional sensitivity of this hair cell embodiment by perturbing the hair in three directions. These tests demonstrate that the magnitude of the sensing current (30–300pA) is significantly affected by direction of perturbation, where the largest signals result from motion of the hair in a direction perpendicular to the plane of the bilayer.Copyright © 2012 by ASME
Technological Innovation and Organizational Survival: A Population Ecology Study of Nineteenth‐Century American Railroads*

The population ecology model of formal organizations is used to study how adaptive maneuvers enable organizations to maintain themselves in a distribution of like organizations and, ultimately, to ...
Kinetic energy exchanges between the time scales of ENSO and the Pacific decadal oscillation

This paper examines the non-linear kinetic energy interactions of the atmospheric ENSO and decadal oscillations over the Pacific. The calculations are based on a 54-year dataset of tropospheric winds from NCEP reanalysis. We verify that the decadal oscillations have two dominant modes, corresponding well to the pentadecadal and bidecadal modes reported in the literature. Energy interactions involving the range of decadal oscillations and the range of ENSO oscillations are considered in the context of kinetic energy exchanges in the frequency domain. We quantify the relative amplitudes and spatial structures of the quadratic and triplet terms of the kinetic energy exchanges over the Pacific and conclude that quadratic interactions with the mean flow are the dominant term in the kinetic-to-kinetic energy exchanges. Additionally, we show that triplet interactions provide a non-trivial contribution to the total. The interactions between the range of decadal oscillations and the range of ENSO oscillations are found to be the strongest near the regions of maximum oscillation amplitude and of the maximum oscillation amplitude gradient. Due to their similar spatial structures, the two dominant ENSO modes and the bidecadal mode are found to interact in a resonant way. The interactions among the range of ENSO modes and the range of decadal modes are found to strengthen the ENSO modes in the equatorial, subtropical and midlatitude belts, and to weaken the decadal modes in all but the equatorial belt.
TRANSPIRATION COOLING OF A CONSTRICTED ELECTRIC-ARC HEATER.

The performance capability of a transpiration-cooled constricted arc heater has been analyzed. A first approximation using an integral form of the energy equation determines the constrictor length required to develop the temperature field. A similarity solution of the differential equations expressing conservation of mass, momentum, and energy is then obtained for the developed flow. Limitations on the arc performance are investigated, and the transpiration-cooled arc is compared with an arc having a water-cooled constrictor. Numerical calculations for hydrogen at atmospheric pressure indicate that higher peak temperatures can be expected with the transpiration-cooled arc, whereas the maximum mass-flow averaged enthalpy is approximately the same for both types.
Efficient plant regeneration from protoplasts of Arachis paraguariensis Chod. et Hassl. using a nurse culture method

An efficient protocol has been developed for protoplast culture and plant regeneration from wild peanut (A. paraguariensis) using a nurse culture method. Protoplasts were isolated from suspension cultures initiated from leaf-derived callus, imbedded in agarose blocks and co-cultured with nurse cells of the same species. Up to 10% of the protoplasts divided and formed compact callus colonies. The protoplast plating efficiency was correlated with both the length of the nurse cell co-cultivation period and the protoplast plating density. The optimal nurse culture duration was 14 d. The optimal plating density was 2×104 protoplasts/ml plating medium. Multiple shoots (up to 10 shoots per colony) were readily regenerated from protoplast-derived callus after transfer of callus to semi-solid modified MS medium containing 0.5 mg l-1 NAA and 1 mg l-1 BA. Plantlets with normal leaflets were obtained by rooting shoots on porous rootcubes saturated with modified MS medium containing 1 mg l-1 NAA.
A multivariate analysis of long-term care nursing services.

Marketing, as a useful conceptual framework, has been extended to a variety of nonprofit sectors including the health care industry. Despite ever growing literature devoted to general health care marketing, there appears to be a dearth of specific application-oriented studies. This paper illustrates the development and application of a multiple discriminant analysis model in the context of long-term care (LTC) facilities. Empirical findings are presented and factors affecting the occupancy rates are discussed with implications for marketers, managers and administrators of skilled LTC nursing homes.
Intersections between neurobiology and oncology: tumor origin, treatment and repair of treatment-associated damage

The number of potentially intimate relationships between brain tumors and the precursor cells that contribute to normal central nervous system (CNS) development and repair now appears to be somewhat larger than would have been anticipated only a few years ago. It also appears that understanding the vulnerabilities of CNS precursor cells, and of the specific cells that they generate, might help us to reveal the biological basis for the cognitive impairment that is increasingly recognized as an adverse effect of systemic cancer therapies. Using neural stem cells as therapeutic vehicles in the treatment of brain tumors could be modified to allow repair of the damage caused by brain tumors themselves and of the neurological impairment that is frequently associated with traditional cancer treatment approaches.
Occurrence, fate and removal of synthetic oral contraceptives (SOCs) in the natural environment: A review

Synthetic oral contraceptives (SOCs) are a group of compounds with progestagenic and/or androgenic activities, with some also possessing estrogenic activities. Recent research has documented that some of these emerging contaminants have adverse effects on aquatic organisms at very low concentrations. To facilitate the evaluation of their latent risks, published works on their occurrence and fate in the environment are reviewed. Androgenic/progestagenic relative potencies or relative binding affinity of these SOCs as well as their physicochemical properties and toxicity are summarized. Appropriate analytical methods are outlined for various environmental sample types, including methods of sample preparation and limit of detection/quantification (LOD/LOQ). Finally results on their occurrence and fate in wastewater treatment plants (WWTPs) and other environments are critically examined.
Synchronous Motor Railcar Propulsion

Development of ac motor drives for rail transit car has centered on the induction motor with pulsewidth modulated (PWM) inverter control. Interest in the induction motor as a replace for the series dc traction motor stems from the simplicity of the squirrel cage rotor of the induction motor. In this article, the short-comings of PWM inverter-induction motor transit car drive are examined. It is shown that the synchronous, or brushless dc, motor drive can provide performance exceeding both the PWM inverter-induction motor and the conventional dc motor in the transit car application.
Equilibration of Two-Dimensional Double-Diffusive Intrusions

Abstract This paper considers the equilibration of lateral intrusions in a doubly diffusive fluid with uniform unbounded basic-state gradients in temperature and salinity. These are density compensated in the horizontal direction and finger favorable in the vertical direction. Previous nonlinear studies of this effect have qualitative and quantitative limitations because of their fictitious parameterizations of the weak “turbulence” that arises. Here, two-dimensional direct numerical simulations (DNS) that resolve scales from the smallest to the intrusive are used to predict the equilibrium state. This is achieved by numerically tilting the x–z computational box so that the mean intrusion is represented by a mode with no lateral variation, but smaller-scale 2D eddies comparable to the intrusion thickness are resolved. The DNS show that the initial plane wave intrusion evolves to an equilibrium state containing both a salt finger interface and a diffusive interface, surrounded by well-mixed layers. The inv...
The influence of water and LPO on the initiation and evolution of mantle shear zones

Abstract We present data from the Josephine Peridotite (SW Oregon, USA) that constrain the underlying physical processes responsible for the initiation of shear localization and the evolution of ductile shear zones in Earth's mantle. Field measurements of narrow (2–60 m wide) ductile shear zones in harzburgite were used to construct strain profiles, which have maximum shear strains ranging from γ=5.25 to γ>20. Measurements of pyroxene water concentrations from harzburgite samples within and immediately adjacent to the shear zones indicate that gradients in water concentration exist on a 10–100 m scale, even after exhumation. Water concentration measurements are correlated with olivine lattice-preferred orientation (LPO), corroborating experimental results on the influence of water on slip system activity. Using empirical olivine flow laws and the diffusivity of water in olivine, we model initiation of a ductile shear zone through localized water weakening. We demonstrate that this mechanism can readily generate spatial perturbations in both effective viscosity and strain. However this model is not able to reproduce both the observed shear strain gradients and water concentration data from the Josephine shear zones. We evaluate other plausible localization mechanisms, which may amplify this initial strain perturbation. The most relevant at these conditions is the development of viscous anisotropy associated with the evolution of olivine LPO. Using recent experimental results, we demonstrate that progressive rotation of olivine LPO into the shear plane enhances deformation within a shear zone. We conclude that feedback between at least two microphysical processes is needed to account for observed outcrop-scale shear localization.
Low-temperature reactively sputtered iron oxide for thin film devices

The development of a low-temperature reactive-sputtering process for producing high-quality hematite films was explored. Iron oxide thin films were sputter-deposited under different conditions of oxygen partial pressure and at substrate temperatures up to 200 °C, and characterized for comparison. Although all sample films exhibited structural and compositional characteristics consistent with polycrystalline rhombohedral Fe2O3 (hematite), it was found that the detailed grain features and morphology, as well as the optical and electrical properties, were significantly altered by process parameter variations. Average grain size increased with deposition temperature and decreased with oxygen partial pressure. Measured film conductivities ranged from 10−9 S/cm in 100 °C samples up to 5×10−4 S/cm in the 200 °C samples. Highest conductivities were found in the sample films exhibiting the largest grains, which is attributed to the effects of mobility enhancement through reduced inter-grain scattering.
Interactions of galactosyltransferase with serum and secretory immunoglobulins and their component chains.

Abstract Assay of the activity of β-1,4-galactosyltransferase (β-1,4-GT) revealed that in addition to serum, milk, colostrum, amniotic and cerebrospinal fluids and malignant effusions, this enzyme is present also in tears and saliva. Molecular-sieve chromatography of human colostral whey and serum and subsequent assay of β-1,4-GT activity have shown that β-1,4-GT was present as a free enzyme (55 kDa) and associated with components of larger molar mass. The elution pattern did not change when the chromatography was carried out in a buffer devoid of, or enriched with, Mn2+, a cofactor of β-1,4-GT activity. However, the activity associated with the large molar mass components was absent when the chromatography was carried out in the presence of a chelating agent (EDTA). Analyses of the eluted material by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS-PAGE), and by immunodiffusion indicated that the major colostral component in β-1,4-GT activity-containing fractions was secretory IgA (S-IgA); in addition, the β-1,4-GT activity was detected in fractions that contained lactoferrin and α-lactalbumin. Interactions of β-1,4-GT with S-IgA and lactoferrin in colostrum were also demonstrated by the detection of radioactivity in precipitin lines obtained by immunoelectrophoresis and autoradiography of the colostral whey after it had been incubated with UDP-[3H]-galactose. Furthermore, radioactively labeled S-IgA and α-chain were detected when colostral whey incubated with UDP-[3H]-galactose was analyzed by SDS-PAGE under non-reducing and reducing conditions, respectively. In serum, the β-1,4-GT-binding components identified in fractions after molecular-sieve chromatography were IgG, IgA, IgM and transferrin. The binding of β-1,4-GT to immunoglobulins (Ig) was also demonstrated by assaying the β-1,4-GT activity associated with Sepharose-4B-immobilized Ig of various isotypes and molecular forms, which were incubated with colostral β-1,4-GT in the presence of Mn2+. β-1,4-GT measured by enzyme activity was bound to these Ig in order: polymeric IgA2 > monomeric IgA1 = polymeric IgA1 = secretory IgA = pentameric IgM > IgG. Immobilized component chains, namely α, μ and J chains, bound β-1,4-GT more effectively than native Ig. Incubation of the IgA1 myeloma protein with crude human colostral galactosyltransferase in the presence of UDP[3H]-galactose and Mn2+ resulted in galactosylation of both N- and O-linked carbohydrate side chains. This finding suggests that in addition to β-1,4-GT, β-1,3-GT, which is also present in human colostrum, may bind to IgA1 or other suitable substrates. The observed reactivity of some anti-SC antibodies with β-1,4-GT was due either to contamination of the immunogen, or to the sharing of common epitopes, which could be carbohydrates.