cssi/SciSciGPT-SciSciNet huggingface dataset:
Modulation of ATP-induced calcium signaling by progesterone in T47D-Y breast cancer cells.

Extracellular ATP activates purinergic (P2) receptors with an increase in intracellular calcium and phosphorylation of MAPK. In this study we have investigated the effect of progesterone/progestin on ATP-induced calcium mobilization and phosphorylation of the kinase ERK in the T47D-Y breast cancer cell line that exhibits no detectable nuclear progesterone receptor expression. Brief pretreatment with progesterone/progestin results in a dose dependent inhibition of ATP-induced intracellular calcium mobilization, and inhibition of ERK phosphorylation. Response to a cell impermeable ligand and inhibition of the response by an inactivating antibody suggests a mechanism of action at the plasma membrane. These results in T47D-Y cells strongly suggest that progesterone can act in a rapid non-nuclear manner to inhibit extracellular ATP effects on intracellular calcium mobilization and ERK activation. This research provides an example of progesterone action in a breast cancer cell line lacking expression of the classical nuclear progesterone receptors.
The Tricks of the Trade: What Makes Spam Campaigns Successful?

Spam is a profitable business for cyber criminals, with the revenue of a spam campaign that can be in the order of millions of dollars. For this reason, a wealth of research has been performed on understanding how spamming botnets operate, as well as what the economic model behind spam looks like. Running a spamming botnet is a complex task: the spammer needs to manage the infected machines, the spam content being sent, and the email addresses to be targeted, among the rest. In this paper, we try to understand which factors influence the spam delivery process and what characteristics make a spam campaign successful. To this end, we analyzed the data stored on a number of command and control servers of a large spamming botnet, together with the guidelines and suggestions that the botnet creators provide to spammers to improve the performance of their botnet.
Decision‐theoretic finitely iterated prisoner's dilemmas

There is a well-known puzzle involving finitely iterated prisoner's dilemmas (FIPDs). It is the result of the conflict between a pre-theoretic intuition that players faced with a finite sequence of prisoner's dilemmas might cooperate at least once and the game-theoretic contention that both players will defect in all the rounds, a contention that is backed by a seemingly valid backward induction argument (BIA). The proper approach to solving this puzzle begins by examining sets of assumptions that characterize FIPDs to identify the ones that really do entail mutual defection throughout (MDT). Once this first step is accomplished, the second step is to assess these sets. They can be assessed in various ways. For example, we could see what remains of the puzzle: if the only sets that entail the MDT conclusion are very strong (especially in certain unexpected ways), their strength could undermine the pre-theoretic intuition that a player might cooperate. For another example, we might see whether the sets that do entail MDT have any applicability, determining whether any real-life situations could be modelled by these sets. Though the second stage of this two-step approach is interesting and pivotal, I promise not to do any assessing. The current state of the literature requires that some time be spent exclusively on the first step. I will focus my attention on one important set of FIPD assumptions. It includes an assumption describing the basic game configuration (BGC). BGC says that players 1 and 2 will play a prisoner's dilemma n times (n 2 2), that both players will be rational throughout, and that they will remember what happened in the earlier rounds. The set also includes an assumption describing the players' epistemic states vis-ai-vis BGC. I call this the common belief requirement (CBR). It says that both players presently (i.e., just prior to the first round) believe BGC, that both presently believe that they both presently believe BGC, and so on ad infinitum. Officially, that is all that our central set of assumptions includes, just BGC and CBR. There is, however, a lot built into these assumptions: For the purposes of this paper, I will assume that believing is identical to assigning unit probability. For these same purposes, I will also assume that S is rational only if (i) S has coherent probability assignments just prior to each of the rounds, (ii) S updates probability assignments via conditionaliza-
Means of unitaries, conjugations, and the Friedrichs operator

Abstract If C is a conjugation (an isometric, conjugate-linear involution) on a separable complex Hilbert space H , then T ∈ B ( H ) is called C-symmetric if T = C T ∗ C . In this note we prove that each C-symmetric contraction T is the mean of two C-symmetric unitary operators. We discuss several corollaries and an application to the Friedrichs operator of a planar domain.
Effect of saccharide length on the immunogenicity of neoglycoconjugates from synthetic fragments of the O-SP of Vibrio cholerae O1, serotype Ogawa.

Abstract A synthetic hexasaccharide, identical to the terminal hexasaccharide of Ogawa LPS, coupled to bovine serum albumin induced protective antibodies in mice. To determine if there was a minimum saccharide length required for immunogenicity and efficacy, shorter (mono- to pentasaccharide) neoglycoconjugates (CHO–BSA) were tested in mice. The Ogawa CHO–BSA was inoculated at either a constant mass but differing moles, or equal moles but differing masses. Humoral responses were essentially the same when mice received 9 μg of the carbohydrate (0.007 mM with the pentasaccharide) in each of the neoglycoconjugates prepared from mono- through the pentasaccharide, or the same molar amount (0.007 mM), proportionally less by weight when going from the penta- to the monosaccharide. These data show that, within this dose range, the responses occurred virtually independently of the amount of immunogen. Humoral antibodies induced by these immunogens were generally not vibriocidal. Selected antisera induced by CHO–BSA immunogens were protective, but the ELISA titers of the sera were not predictive of the protective capacity. Purified, Ogawa LPS induced anti-Ogawa LPS IgM antibody titers similar to those induced by the Ogawa CHO–BSA conjugates. The anti-whole LPS sera were strongly vibriocidal, as were the previously reported sera induced by hexasaccharide conjugates. This suggests either that the shorter oligosaccharides lack a conformational epitope provided by the hexasaccharide or that the LPS has additional B cell epitopes or selects different B cells in the primary response.
Preparative zone electrophoresis of proteins on polyacrylamide gels in 8 M urea.

Abstract The design and operation of an apparatus for preparative electrophoretic resolution of proteins is described. Recoveries were essentially quantitative, with a number of different model proteins electrophoresed under both acidic and alkaline conditions. It is anticipated that the method will be particularly useful for purification of macromolecules soluble in urea or nonionic detergents, but not in the usual aqueous buffers.
Mutability of bacteriophage M13 by ultraviolet light: Role of pyrimidine dimers

The role of pyrimidine dimers in mutagenesis by ultraviolet light was examined by measuring the UV-induced reversion of six different bacteriophage M13 amber mutants for which the neighboring DNA sequences are known. The mutational response at amber (TAG) codons preceded by a guanine or adenine (where no pyrimidine dimer can be formed) were compared with those preceded by thymine or cytosine (where dimer formation is possible). Equivalent levels of UV-induced mutagenesis were observed at both kinds of sites. This observation demonstrates that there is no requirement for a pyrimidine dimer directly at the site of UV-induced mutation in this single-stranded DNA phage. UV irradiation of the phage was also performed in the presence of Ag+ ions, which specifically sensitize the DNA to dimer formation. The two methods of irradiation, when compared at equal survival levels (and presumably equal dimer frequencies), produced equivalent frequencies of reversion of the amber phage. We believe these results indicate that while the presence of pyrimidine dimers may be a prerequisite for UV mutagenesis, the actual mutagenic event can occur at a site some distance removed from a dimer.
Enhanced performance from high-extraction-efficiency free electron lasers

Abstract Tapering either wiggler wavelengths or wiggler magnetic fields has been used to enhance the extraction efficiency of free electron lasers. For high-extraction-efficiency systems, the electron beam dynamics and thus the system performance can depend on the method of tapering. It is shown that tapering the wiggler wavelength could yield better results for a high-extraction-efficiency system. If aperturing of the optical field by the wiggler becomes significant, a double-taper scheme is proposed that could improve results over a magnetic-field-tapered system.
Parity violation in hot QCD: How to detect it

In a recent paper (hep-ph∕0406125) Kharzeev argues for the possibility of $P$- and∕or $CP$-violation effects in heavy-ion collisions, the effects that can manifest themselves via asymmetry in ${\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}$ production with respect to the direction of the system angular momentum. Here we present an experimental observable that can be used to detect and measure the effects.
Benzotriazoles. Part 151: The preparation of 1-(1-alkenyl)benzotriazoles

The title compounds are prepared either (A) from 1-(1-chloroalkyl)benzotriazoles and aldehydes via Wittig reaction or (B) from 1-[1,1-bis(trimethylsilyl)alkyl]benzotriazoles by alkylative desilylation by fluoride ion in the presence of a carbonyl compound (in one instance by lithiation of the silyl compound and subsequent reaction with a carbonyl electrophile) via a Peterson olefination. The methods are applicable to both alkyl and aryl ketones and to aldehydes, with method (B) giving the highest yields.
Dependence of bilevel mathematical programs on irrelevant constraints

A major topic in aggregation of linear programming problems is the estimation of the aggregation error, i.e., the computation of bounds for the loss of optimality which results from the coarsening of information caused by aggregation. A widely used method to compute bounds for variable-aggregated linear programs was developed by Zipkin [2, p. 41, 3]. Several extensions and modifications have been proposed. We present an overview of these bound computation methods and extend the methods in case that: (1) several dual solutions are available and (2) optimal disaggregation is performed. By means of a small numerical study, indications for the quality of the bounds are derived. The discussion is restricted to column (i.e. variable) aggregation.
Ice-templated porous alumina structures

The formation of regular patterns is a common feature of many solidification processes involving cast materials. We describe here how regular patterns can be obtained in porous alumina by controlling the freezing of ceramic slurries followed by subsequent ice sublimation and sintering, leading to multilayered porous alumina structures with homogeneous and well-defined architecture. We discuss the relationships between the experimental results, the physics of ice, and the interaction between inert particles and the solidification front during directional freezing. The anisotropic interface kinetics of ice leads to numerous specific morphological features in the structure. The structures obtained here could have numerous applications, including ceramic filters and biomaterials, and could be the basis for dense multilayered composites after infiltration with a selected second phase.
Optical emission measurements of electron energy distributions in low-pressure argon inductively coupled plasmas

Optical modeling of emissions from low-temperature plasmas provides a non-invasive technique to measure the electron energy distribution function (EEDF) of the plasma. While many models assume the EEDF has a Maxwell?Boltzmann distribution, the EEDFs of numerous plasma systems deviate significantly from the Maxwellian form. In this paper, we present an optical emission model for the Ar(3p54p ? 3p54s) emission array which is capable of capturing details of non-Maxwellian distributions. Our model combines previously measured electron-impact excitation cross sections with Ar(3p54s) number density measurements and emission spectra. The model also includes corrections for radiation trapping of the Ar(3p54p ? 3p54s) emission lines. Results obtained with this optical technique are compared with corresponding Langmuir probe measurements of the EEDF for Ar and Ar/N2 inductively coupled plasma systems operating under a wide variety of source conditions (1?25?mTorr, 20?1000?W, %N2 admixture). Both the optical emission method and probe measurements indicate the EEDF shapes are Maxwellian for low electron energies, but with depleted high energy tails.
Recent progress in the biochemistry of plant steroids other than sterols (saponins, glycoalkaloids, pregnane derivatives, cardiac glycosides, and sex hormones).

Recent studies concerning the biosynthesis, metabolism, and possible functions of steroids other than sterols in plants are reviewed and discussed. These studies embrace the saponins, glycoalkaloids, pregnane derivatives, cardiac glycosides, as well as their aglycones, and the sex hormones.
Some strategies of reuse in an object-oriented programming environment

In a single-subject study of a software developer working in an object-oriented programming environment, we found evidence of a development style characterized by pervasive software reuse. The subject employed regular strategies for template selection and coding in her work, and avoided techniques requiring deep understanding of code details or symbolic execution whenever possible. Within the limits of the design of the study, the subject's performance is related to attributes of object-oriented programming and our interpretation of the mature mental model with which she approached her task.
Live CDs and security lab configuration

Developing and configuring an information security lab can require a substantial budget, support, and resource commitment. In addition to an appropriate software budget, activities such as installing security software, setting up user accounts, and configuring lab systems can require a significant labor commitment. In a traditional environment, it may also require the semester long dedication of a computer lab to a single security class section. In many educational environments, obtaining these commitments is problematic.To mitigate these problems, we developed a supplementary security lab framework that utilizes Open Source Software and the Knoppix Live CD. By definition, a Live CD is a bootable CD that contains a complete operating system. Some Live CDs, such as Knoppix, also include system utility and application programs. In addition to being self configuring, the Knoppix Live CD may also be remastered to accommodate additional security tools. In this paper, we will present an overview of our supplemental lab framework and its components the Knoppix Live CD and Open Source tools. We will also discuss a sample Live CD based security project that utilizes our supplementary security lab framework.
Regular induction of hypomania by L-dopa in "bipolar" manic-depressive patients.

ALTHOUGH the catecholamine precursor L-dopa (L-3–4-dihydroxyphenylalanine), like most clinically effective anti-depressant drugs, reverses reserpine-induced brain catecholamine depletion and sedation1–3, early clinical trials using 1.5–3.0 g/day revealed no significant antidepressant activity4–9. Recently, we gave L-dopa to eighteen depressed patients, using the very large oral doses found to be effective in reversing many of the symptoms of Parkinson's disease10–17.
Growth and solvent production by Clostridium pasteurianum ATCC® 6013™ utilizing biodiesel-derived crude glycerol as the sole carbon source

The rapidly expending market for biodiesel is dramatically altering the cost and availability of glycerol, as typical biodiesel production processes generate about 10 wt % glycerol. Biodiesel producers have little financial incentive to purify the crude glycerol, and because it contains methanol, crude glycerol is considered a hazardous waste. Therefore, it is critical that new and innovative processes for managing and utilizing the glycerol co-product be developed. In the longer term, as supplies continue to increase, glycerol will become a versatile building block chemical for the production of high value compounds within an integrated biorefinery. This research investigated the value-added conversion of crude glycerol generated during biodiesel production using anaerobic fermentation. Pure cultures of Clostridium pasteurianum have been shown to produce significant amounts of butanol and 1,3-propanediol when utilizing purified glycerol as the sole substrate. Butanol is of particular interest as a renewable biofuel, as it has a higher heating value, higher octane number, lower vapor pressure, and higher miscibility than ethanol, making butanol preferable to ethanol for blending with petroleum fuels. Preliminary experiments compared growth and product formation of C. pasteurianum (ATCC ® 6013 ™ ) utilizing both purified and biodiesel-derived crude glycerol as the sole carbon source in batch culture. Cultures utilizing crude glycerol demonstrated significant growth and production of butanol, 1,3-PDO, and ethanol at concentrations up to 25 g/L crude glycerol. This work is significant in that it is the first report of butanol production from crude glycerol using this organism. The maximum yield of butanol produced from pure glycerol was 0.36 g/g, while the maximum butanol yield produced from crude glycerol was 0.30 g/g. These yields are substantially higher than the 0.15―0.20 g/g butanol yield typically achieved during the fermentation of glucose using C. acetobutylicum. These results indicate that biodiesel-derived crude glycerol is a promising, low-cost, renewable feedstock for butanol production.
Isotopic characterization of NO adsorption, dissociation and coadsorption with CO on Pt(100) : An infrared reflection-absorption study

We present the results of the in situ infrared study of the behavior of NO with CO on Pt(100) carried out in a continuous flow reactor at 470 K and 500 K. The frequency of the solitary IR band observed at 470 K during adsorption of nitric oxide shifted by 68-73 cm -1 when we used 15 N 18 O instead of NO. This shift corresponds closely to the square root of the ratio of reduced masses, [μ(NO)/μ 15 N 18 O)] 1/2 , indicating that NO is molecularly adsorbed on the platinum surface even at temperatures as high as 470 K. We did not observe any molecular adsorption of NO at 500 K, though. However, we observed the appearance of an infrared band at ∼1630 cm -1 during the reaction of CO and NO both at 470 K and 500 K. The peak absorbance of this band appears to correlate with high rates of CO 2 production. On the other hand, at low reaction rates, this band completely disappears and is replaced by infrared bands that correspond to a growth of CO adlayer. Isotopic studies utilizing C 18 O showed that the ∼1630 cm -1 wavenumber band is due to molecularly adsorbed NO, indicating that nitric oxide exists largely in undissociated state during its interaction with CO on Pt(100) at elevated temperatures.
Embedding and extending GIS for exploratory analysis of large-scale species distribution data

Exploratory analysis of large-scale species distribution data is essential to gain information and knowledge, stimulating hypotheses and seeking possible explanations of species distribution patterns. Geographical Information System (GIS) has played an important role in modeling and visualizing species distribution patterns for a single or a limited number of species. However, traditional GIS models do not take taxonomic components of species distribution data into consideration and are neither effective nor efficient in managing large-scale species distribution data.In this study, we propose to embed and extend GIS for large scale species distribution data analysis. We provide an integrated data model that seamlessly links geographical, taxonomic and environmental data related to species distribution data analysis. We then present LEEASP (a Linked Environment for Exploratory Analysis of large-scale Species Distribution data), a prototype that has been developed based on the integrated data model. LEEASP utilizes the state-of-the-art advanced visualization techniques and multiple view coordination techniques to visualize different data sources that are relevant to species distribution data analysis. The North America tree species distribution data and other related data are used as an example to demonstrate the feasibility of the realization of the proposed integrated data model and how LEEASP can help users explore the geographical-taxonomic-environmental relationships
Relaxation of candidate electron spin qubits

We have recently measured pulsed electron spin resonance (ESR) from electrons bound to donors in silicon. Measurements made in the late 1950's showed that these spins were long-lived, but we find coherence times that are about two orders of magnitude longer than previously seen. We have also measured the spin-decoherence of free, 2- dimensional electrons in an ultra-high mobility Si/SiGe quantum well. The coherence time of the 2D electron spins is long in comparison to compound semiconductor systems, but several orders of magnitude shorter than that of the donorbound electrons. Spin-orbit coupling in the form of the Structural Inversion Asymmetry (Rashba effect) appears to be the cause of the increased decoherence rate of the 2D electrons' spin. For architectures employing quantum dots at a heterointerface, the Rashba effect is not expected to cause a loss of spin coherence while the electron is in the ground state, but thermal excitation to upper dot levels could lead to decoherence. We discuss ways in which this Rashba term can be minimized in Si-based structures, as well as other physical systems (electrons on liquid helium, for example) in which much longer spin coherence times can be expected.
Ototoxicity of Toluene in Rats

Abstract Toluene is a major industrial solvent and substance of abuse which is ototoxic in rats as shown by both behavioral testing and measurement of brainstem auditory evoked response (BAER) thresholds. The objective of this investigation was to examine the morphological (hair cell loss) and functional (BAER threshold elevations) changes resulting from toluene administration. In the preliminary experiment, 5 male Sprague-Dawley rats were dosed by gavage to 0.5 ml toluene/kg body weight/day in corn oil for 21 days then consecutively to 1.0 ml toluene/kg/day for 21 days. In the main experiment, eight male Sprague-Dawley rats were dosed by gavage for eight weeks with 1.0 ml toluene/kg body weight/day in corn oil. Five and six control rats, respectively, received corn oil only. BAER thresholds were recorded from four toluene-treated and four control rats prior to dosing (main experiment) and from all rats after dosing (both experiments). Loss of outer hair cells occurred in all toluene-treated rats in the middle and basal turns of the organ of Corti, with the greatest loss in the third row and progressively less in the second and first rows. This loss was more severe in toluene-treated rats that demonstrated elevated BAER thresholds in midfrequency regions, typically 2–8 kHz. These experiments demonstrate that auditory changes are associated with cochlear hair cell loss in toluene-treated rats. These ototoxic effects of toluene contrast with those of other known ototoxicants, e.g., aminoglycoside antibiotics, in terms of the position of hair cell lesion in the organ of Corti and in the pattern of hair cell loss.
Defining an evidence-based cutpoint for medication adherence in heart failure.

Background Despite the importance of medication adherence in heart failure, clinically relevant cutpoints for distinguishing the level of adherence associated with outcomes are unknown. Objective The purpose of this study is to determine the cutpoint above which there is a positive relationship between level of medication adherence and event-free survival. Methods This was a longitudinal study of 135 patients with heart failure. Medication adherence was measured using a valid and objective measure, the Medication Event Monitoring System. Two indicators of adherence were assessed by the Medication Event Monitoring System (AARDEX, Union City, CA): (1) dose count, percentage of prescribed doses taken, and (2) dose days, percentage of days the correct number of doses was taken. Patients were followed up to 3.5 years to collect data on outcomes. A series of Kaplan-Meier plots with log-rank tests, Cox survival analyses, and receiver operating characteristic curves were assessed comparing event-free survival in patients divided at one-point incremental cutpoints. Results Event-free survival was significantly better when the prescribed number of doses taken (dose count) or the correct dose (dose day) was ≥88%. This level was confirmed in a Cox regression model controlling for age, gender, ejection fraction, New York Heart Association, comorbidity, angiotensin-converting enzyme inhibitor use, and β-blocker use. Receiver operating characteristic curves showed that adherence rates above 88% produced the optimal combination of sensitivity and specificity with respect to predicting better event-free survival. With 88% as the adherence cutpoint, the hazard ratio for time to first event for the nonadherent group was 2.2 by dose count ( P = .021) and 3.2 by dose day ( P = .002). Conclusion The results of this study provide clinicians and researchers with an evidence-based recommendation about the level of adherence needed to achieve optimal clinical outcomes.
Commentary: Roles, opportunities, and challenges—science museums engaging the public in emerging science and technology

Even a cursory reading of the public engagement in science (PES) literature over the past decade reveals that public engagement is becoming part of the “orthodoxy of 21st century science policy” (Stilgoe, Nanodialogues: experiments in public engagement with science, 2007, p 16), Moving forward, there appears to be strong consensus that (1) public engagement is an essential component for shaping sound science policies, research agendas, and governance structures; (2) more opportunities for accessible and successful PES need to be developed and implemented to have meaningful impact; and (3) a broader and more diverse range of publics need to be reached through PES activities. This article explores the role that U.S. science museums and centers could play in creating and delivering PES programming focusing on current science and technology developments and issues, with particular attention to nanoscience and nanotechnology. Also addressed will be some of the factors that support increased PES involvement by museums, some of the challenges museums need to overcome to sustain ongoing PES, and several recommendations to achieve broader PES impact through science museum participation.
Laser Beam Shaping

Laser beam shaping is the process of redistributing the irradiance and phase of a beam of optical radiation. This process of controlling optical beams is an enabling technology, which is used in a number of sectors of scientific, engineering, and industrial R&D. The shape of a laser beam generally refers to its irradiance profile, while the phase of a beam generally affects its propagation characteristics. Earlier work of Frieden and Kreuzer during the 1960s articulated well the goals of some contemporary laser beam shaping applications. Namely, geometrical optics was used to determine the configuration of a twoelement optical system that would transform an input plane wave with a Gaussian irradiance profile into an output plane wave with uniform irradiance. For some contemporary applications, physical optics must be used for the optical design of the laser beam shapers. A general presentation of the theory and techniques of laser beam shaping is given in a book edited by Dickey and Holswade. Laser beam shaping has become an important component of many laser-based applications, such as materials processing, medical applications, lithography, optical data storage, laser printing, isotope separation, optical data processing, and laboratory research. The first conference on laser beam shaping was held in 2000 at the Annual Meeting of the SPIE. This Laser Beam Shaping conference included a discussion of the fundamental limits of any beam shaping technique and the foundation for successful beam shaping design, including geometric techniques and optimization-based techniques. Applications included high-power laser fiber injection, UV and deep-UV homogenizers, micromachining in the electronics industry, and beam shaping techniques for laser printing. The Laser Beam Shaping II conference continued to bring together both workers in the field and potential users of the technology. Theory and design was again addressed, but the papers were primarily in the area of de-
Modulation of Urethane (Ethyl Carbamate) Carcinogenicity by Ethyl Alcohol: A Review:

Urethane (ethyl carbamate) is a carcinogen that has been detected as a contaminant in certain foods and alcoholic beverages. The carcinogenicity of urethane appears to be mediated through a metabolic pathway involving sequential cytochrome P-450-catalyzed oxidation to vinyl carbamate and vinyl carbamate epoxide, the latter of which reacts with DNA to yield etheno-type DNA adducts. The interactions of ethanol on urethane metabolism and carcinogenicity are varied and complex. Urethane is oxidized by cytochrome P-450 IIE1, an isoform induced by ethanol, which suggests that chronic ethanol consumption could increase the oxidation of urethane to its epoxide derivative. On the other hand, ethanol coadministration is known to inhibit the elimination and hydrolysis of urethane. Ethanol has decreased the tumorigenicity of urethane in two bioassays, but did not have an effect in a third. While the results to date suggest that ethanol will decrease the metabolic activation of urethane, with a resultant decrease in tumorigenicity, additional studies are clearly necessary to elucidate the mechanisms by which ethanol influences the carcinogenicity of urethane.
A clinician's guide to systematic reviews.

The purpose of this article is to discuss systematic reviews, how they are performed, and their associated strengths and limitations. A systematic review is an assessment of evidence involving exact methods to systematically identify, select, and critically evaluate all available literature on a particular topic. Unlike most narrative reviews, systematic reviews have defined methods established a priori for searching, evaluating, extracting, synthesizing, and reporting available evidence. Key characteristics differentiating systematic reviews from most narrative reviews include: clearly stated objectives, pre-defined inclusion/exclusion criteria, an explicit reproducible methodology, systematic exhaustive searches to identify all sources of evidence, an assessment of the validity for each included study, and a systematic presentation of the study characteristics/results. Though there are significant advantages to systematic reviews, there are also clear limitations such as: the quality of included evidenc...
Detection and quantification of bacterial biofilms combining high-frequency acoustic microscopy and targeted lipid microparticles

Background: Immuno-compromised patients such as those undergoing cancer chemotherapy are susceptible to bacterial infections leading to biofilm matrix formation. This surrounding biofilm matrix acts as a diffusion barrier that binds up antibiotics and antibodies, promoting resistance to treatment. Developing non-invasive imaging methods that detect biofilm matrix in the clinic are needed. The use of ultrasound in conjunction with targeted ultrasound contrast agents (UCAs) may provide detection of early stage biofilm matrix formation and facilitate optimal treatment. Results: Ligand-targeted UCAs were investigated as a novel method for pre-clinical non-invasive molecular imaging of early and late stage biofilms. These agents were used to target, image and detect Staphylococcus aureus biofilm matrix in vitro. Binding efficacy was assessed on biofilm matrices with respect to their increasing biomass ranging from 3.126 × 10 3 ± 427 UCAs per mm 2 of biofilm surface area within 12 h to 21.985 × 10 3 ± 855 per mm 2 of biofilm matrix surface area at 96 h. High-frequency acoustic microscopy was used to ultrasonically detect targeted UCAs bound to a biofilm matrix and to assess biofilm matrix mechanoelastic physical properties. Acoustic impedance data demonstrated that biofilm matrices exhibit impedance values (1.9 MRayl) close to human tissue (1.35 - 1.85 MRayl for soft tissues). Moreover, the acoustic signature of mature biofilm matrices were evaluated in terms of integrated backscatter (0.0278 - 0.0848 mm -1 ×s r -1 ) and acoustic attenuation (3.9 Np/mm for bound UCAs; 6.58 Np/mm for biofilm alone). Conclusions: Early diagnosis of biofilm matrix formation is a challenge in treating cancer patients with infection-associated biofilms. We report for the first time a combined optical and acoustic evaluation of infectious biofilm matrices. We demonstrate that acoustic impedance of biofilms is similar to the impedance of human tissues, making in vivo imaging and detection of biofilm matrices difficult. The combination of ultrasound and targeted UCAs can be used to enhance biofilm imagingand early detection. Our findings suggest that the combination of targeted UCAs and ultrasound is a novel molecular imaging technique for the detection of biofilms. We show that high-frequency acoustic microscopy provides sufficient spatial resolution for quantification of biofilm mechanoelastic properties.
Strain-induced crystallization and melting behavior of polyetheramide block copolymer

The soft segment of poly (polyamide-polytetramethylene glycol) esters crystallize at strains beginning at about 500%, raising the observed crys tal melting temperature from about 7 to 38°C. Accompanying the strain- induced crystallization, the polymer hardens, changing from elastic to plastic. Upon melting of the PTMO crystallites, Pebax reasserts its elastic character.
Dipole quantum beats of dynamically interacting excitons

Summary form only given. We use spectral interferometry and temporal gating techniques to investigate the time-integrated quantum beats (TI-QBs) involving the light hole (lh) and heavy hole (hh) excitons in GaAs-AlGaAs quantum wells in a geometry that is sensitive both to the nonradiative Raman coherence and to the radiative dipole coherence associated with the dynamic interactions between hh and lh excitons. We then use the polarization of the incident light and the selection rules for the hh and lh transitions to isolate the contributions of the dynamic coupling between the excitons.
Effects of Alternating Current Iontophoresis on Drug Delivery

Abstract Objective: The duration of direct current (DC) iontophoresis is limited to 10- to 15-minute periods because of electrochemical burns from hydrogen and hydroxide ions generated by the DC current. A new iontophoretic device, the Lectro Patch, uses a low-frequency alternating current (AC). AC current is theorized to generate H + ions during one phase and OH − when the current reverses polarity, thus possibly neutralizing pH changes and avoiding burns. This study examined this possibility and evaluated drug delivery with AC iontophoresis, using hydroxocobalamin. Design: A known amount of hydroxocobalamin dissolved in 6mL of water was loaded in Lectro Patches, two of which were then taped on the forearms of 10 patient volunteers. One patch was activated to deliver drug by AC iontophoresis. The second patch was not activated and served as a control for delivery by diffusion. Trials were run for 2 and 4 hours, with both 1,000 μ g/mL and 2,000 μ g/mL concentrations. Setting: Study was conducted with in patients in an extended care setting using volunteers. Main Outcome Measures: Amounts of hydroxocobalamin remaining in the Lectro Patches after iontophoresis were assayed by spectrophotometry. Data were analyzed by ANOVA. Results: No burns occurred. Significantly greater losses occurred with 4 hours of iontophoresis than with 2 hours ( p Conclusions: AC iontophoresis avoids electrochemical burns; charged drugs can be delivered by AC iontophoresis; and delivery of drug increases with duration of application.
Peripheral augmentation index and vascular inflammation in autosomal dominant polycystic kidney disease

Background. Cardiovascular disease is the leading cause of premature mortality in autosomal dominant polycystic kidney disease (ADPKD). We examined peripheral augmentation index (AIx) as a measure of systemic vascular function and circulating markers of vascular inflammation in patients with ADPKD. Methods. Fifty-two ADPKD patients with hypertension and estimated glomerular filtration rate (eGFR) 0.05). ICAM, P-selectin, E-selectin and sFas were higher and FasL lower in all ADPKD groups compared to controls (P 0.05). According to multiple regression analysis, predictors of AIx in ADPKD included age, height, heart rate and mean arterial pressure (P < 0.05). Vascular inflammatory markers were not predictors of AIx in ADPKD. Conclusions. Systemic vascular dysfunction, manifesting as an increase in AIx and vascular inflammation is evident in young normotensive ADPKD patients with preserved renal function. Vascular inflammation is not associated with elevated AIx in ADPKD.
Regulation of B lymphocyte activation by the Fc portion of immunoglobulin

Murine splenic B lymphocytes are induced to proliferate and undergo polyclonal activation in the presence of Fc fragments, AHGG, antigen-antibody complexes, and CH3 fragments derived from plasmin digestion of human Ig. The unifying feature of the polyclonal antibody response induced by these agents is that in all cases a portion of the constant region of the Ig molecule (ie, Fc region) is present. Fragments of Ig lacking the Fc piece, such as Fab and F(ab′)2 were found not to be stimulatory. In addition, a model is proposed to account for the regulatory effects of antigen-antibody complexes on an ongoing humoral immune response.
Efficient Catalysis of Polysiloxane Synthesis by Silicatein α Requires Specific Hydroxy and Imidazole Functionalities

A protein isolated from a biosilica (shown schematically) catalyzes alkoxysilane polycondensation at neutral pH values and low temperatures. Replacement of either of two specific side chain functionalities (Ser-26 and His-165) significantly diminishes catalysis, supporting a reaction mechanism analogous to that of a well-known enzyme that is highly homologous to the silica protein. These results may be useful in the development of synthetic catalysts for environmentally benign synthesis of polysiloxanes.
Directed differentiation of human pluripotent stem cells into intestinal tissue in vitro

Studies in embryonic development have guided successful efforts to direct the differentiation of human embryonic and induced pluripotent stem cells (PSCs) into specific organ cell types in vitro. For example, human PSCs have been differentiated into monolayer cultures of liver hepatocytes and pancreatic endocrine cells that have therapeutic efficacy in animal models of liver disease and diabetes, respectively. However, the generation of complex three-dimensional organ tissues in vitro remains a major challenge for translational studies. Here we establish a robust and efficient process to direct the differentiation of human PSCs into intestinal tissue in vitro using a temporal series of growth factor manipulations to mimic embryonic intestinal development. This involved activin-induced definitive endoderm formation, FGF/Wnt-induced posterior endoderm pattering, hindgut specification and morphogenesis, and a pro-intestinal culture system to promote intestinal growth, morphogenesis and cytodifferentiation. The resulting three-dimensional intestinal 'organoids' consisted of a polarized, columnar epithelium that was patterned into villus-like structures and crypt-like proliferative zones that expressed intestinal stem cell markers. The epithelium contained functional enterocytes, as well as goblet, Paneth and enteroendocrine cells. Using this culture system as a model to study human intestinal development, we identified that the combined activity of WNT3A and FGF4 is required for hindgut specification whereas FGF4 alone is sufficient to promote hindgut morphogenesis. Our data indicate that human intestinal stem cells form de novo during development. We also determined that NEUROG3, a pro-endocrine transcription factor that is mutated in enteric anendocrinosis, is both necessary and sufficient for human enteroendocrine cell development in vitro. PSC-derived human intestinal tissue should allow for unprecedented studies of human intestinal development and disease.
Population structure delineated with microsatellite markers in fragmented populations of a tropical tree, Carapa guianensis (Meliaceae)

Deforestation and selective logging in the tropics may have serious consequences on genetic processes in tropical tree populations, affecting long-term survival of a given species as well as tropical forest communities. Because understanding the effects of human-induced changes on genetic processes is of utmost importance in formulating sound conservation and management plans for tropical forest communities, we developed microsatellite or simple sequence repeat (SSR) markers for the tropical tree Carapa guianensis (Meliaceae) and assessed the polymorphism of SSRs in adult and sapling populations in a large contiguous forest and in selectively logged and fragmented forests. The number of alleles in polymorphic loci ranged between 4 and 28. No inbreeding was detected in saplings or adult cohorts, but the allelic richness was lower in the sapling cohort of the isolated fragment. Genetic distances, Nei’s D and ( δμ ) 2 , and R ST values among saplings were greater than among adult cohorts, suggesting restriction of gene flow due to deforestation and habitat fragmentation. These SSR loci may be used to address many related questions regarding the population and conservation genetics of tropical trees.
Strategies used by chronically ill older women and their caregiving daughters in managing posthospital care

The purpose of this grounded theory study was to learn how older women and their caregiving daughters managed care following the mother's hospitalization because of a chronic illness. Data were collected in semi-structured interviews with 33 mother-daughter pairs at two weeks post-discharge, and 32 pairs two months post-discharge. Content analysis and constant comparison were used in analysing the data. The findings indicate that the posthospital period for both mothers and daughters was characterized by difficulties in managing care that were often related to lack of information about diet, medications and community services. In dealing with the difficulties, most mothers and daughters employed information-seeking and problem-solving strategies to move from the phase, finding out what works, to establishing new routines. Not all mothers and daughters established routines by two months post-discharge. Nurses need to recognize factors that impede mothers and daughters in establishing routines in order to design effective interventions to ease the posthospital transition.
Driver safety and motor carrier profitability : identifying and understanding drivers in the fleet

The objective of the study was to quantitatively explore truck driver safety records in an effort to determine and classify various types of drivers. Six safety variables relating to the number of safety points each driver had accumulated were analyzed using a cluster analysis procedure on 368 active drivers. The results of the study identified three clusters of drivers. Over 49.3 percent of the drivers were identified in a cluster labeled as the “Best Drivers.” The label “Ticket Magnets” was given to 23.6 percent of the drivers, and 27.1 percent of the sample was given the label “Accident Prone.” The individual clusters were also profiled on additional variables. The study findings indicate that most drivers are very good in all aspects of driver safety. Other drivers have some deficiencies which are addressed as managerial implications in the manuscript.
Inferior gluteal artery perforator flap breast reconstruction

Abstract Background In thin patients or in those with prior surgery that precludes the use of abdominal tissue for autologous breast reconstruction, the skin and fat of the lower buttock, perfused by perforating branches of the inferior gluteal artery, has been proposed as an alternative. Methods This study reviewed 19 reconstructions based on the inferior gluteal artery that were performed between July 2001 and March 2007. Patient characteristics, cancer stage and treatment, indications for use of gluteal tissue, surgical time, length of hospitalization, and complications were recorded. Results Our average patient age was 49 years, with early stage breast cancer, and low body mass index. The average surgical time was 9 hours and 7 minutes, and the average hospitalization time was 4 days. Complications included 2 complete flap losses, seromas, and delayed donor site healing. Conclusions We conclude that tissue from the lower buttock, perfused by branches of the inferior gluteal artery, is a useful alternative for autologous breast reconstruction.
Effective "homework-free" BME physiology instruction

A method of teaching physiology that involved instant feedback on quizzes and in-class activities in lieu of homework was compared to more traditional instruction including homework. The comparison was conducted in an undergraduate biomedical engineering course. Results demonstrated no significant difference in exam scores for the two groups, calling into question the utility of homework as a learning activity for physiology instruction. The results of the experiment may have been affected by the terrorist attacks of Sept 11, 2001.