cssi/SciSciGPT-SciSciNet huggingface dataset:
Preparation of polyethylene glycol-tissue plasminogen activator adducts that retain functional activity: characteristics and behavior in three animal species

Conditions were defined for the derivatization of recombinant tissue plasminogen activator (rt-PA) with polyethylene glycol (PEG) so as to retain functional activity as a possible means of producing a t-PA species with a prolonged circulating lifetime. Derivatives with a wide range of retention of activities were prepared by varying the concentration and species of activated PEG. The specific activities of the PEG-rt-PA derivatives were dependent on the method of assay. Assays using preformed fibrin gave higher estimates of retention of activity than assays using soluble components. Plasma elimination studies in mice and rats indicated prolonged circulating lifetimes for the radiolabeled PEG-rt-PA derivatives after a rapid clearance and distribution phase; however, the disappearance of functional activity was much more rapid than the disappearance of radiolabeled material. The PEG-rt-PA derivatives appeared to accumulate in tissues above their interstitial fluid concentrations and were rapidly inactivated, apparently by reaction with the plasma protease inhibitors. These results were consistent with the inactivation of the PEG-rt-PA derivatives in rat plasma in vitro. A somewhat longer half-life (t1/2) of the one derivative studied was observed in dogs (t1/2, 16 minutes) as compared with the rat (t1/2, five minutes). This was sufficient to confer thrombolytic activity upon the derivative (administered by bolus injection) in contrast to native rt-PA. The potential of PEG-modified rt-PA as a long-lived thrombolytic agent in humans will depend, however, on whether there will be a further extension of the t1/2 because of a reduction in clearance and/or a reduction in the rate of inactivation.
Comment on ‘Initiation of chromosome replication controls both division and replication cycles in E. coli through a double-adder mechanism’

Witz et al. (eLife, 2019) recently performed single-cell mother machine experiments to track growth and the replication cycle in E. coli. They analyzed the correlation structure of selected parameters using both their data and published data, and concluded that E. coli cell-size control is implemented at replication initiation, which challenged the newly emerged division-centric mechanism of cell-size control in bacteria. We repeated Witz et al.9s analysis, and performed additional experiments and analytical calculations. These results explain Witz et al.9s observation and in fact support the division-centric model.
The rapid N-wave as a potentially useful measure of the photopic negative response

The photopic negative response (PhNR) correlates with ganglion cell function and has previously been examined as an indicator of glaucomatous optic nerve damage. However, it is a prolonged response that is measured against baseline, and its clinical utility has been limited by extensive variability, poor repeatability, and baseline instability. We have observed a distinct brief negative wave (“N-wave”) commonly present within the slow PhNR trough, which may provide practical and analytic advantages as a clinical measure. We reviewed data from an interventional trial of 59 glaucoma patients who had 4 exams over an 8-month period. The PhNR was recorded with standard ISCEV stimuli (1 Hz and in some cases 4 Hz stimulation), and N-waves were measured manually, relative to return to baseline. N-waves, when present, could be measured easily despite shifting baselines and a degree of background noise. The PhNR median amplitude centered around 18 μV, while the N-wave median centered around 7 μV, with a distribution of responses skewed toward low or zero amplitudes. The N-wave appears to be a component of the longer PhNR, though its exact origin and significance remain unclear. As a rapid waveform that is independent of baseline, the N-wave is in many ways easier to measure accurately than the slower PhNR, which is highly dependent on baseline stability. The N-wave may prove useful clinically if further studies can optimize its stimulation, show its behavior in normal individuals and find correlation with markers of optic nerve disease.
Confirmatory non-invasive and non-destructive identification of poison ivy using a hand-held Raman spectrometer

Poison ivy (Toxicodendron radicans) is a forest understory plant that grows throughout the United States, Canada and Mexico. The plant contains urushiol oils, a mixture of pentadecylcatechols, that cause severe allergic reactions on skin including reddish inflammation, uncoloured bumps and blistering. Such allergic reactions develop within hours or days, which facilitates unknowing spread of the urushiol inside the house. This enables continuous contact with urushiol extending the length of time of the rash. It should be noted that apart from extensive washing with soap and cold water, there is no direct way to treat urushiol-induced allergic reactions. In these circumstances, the best practice is to avoid contact with the plant. However, differentiating poison ivy from other plants requires sophisticated botanical experience that is not possessed by a vast majority of people. To overcome this limitation, we developed a confirmatory, label-free, non-invasive and non-destructive approach for detection and identification of poison ivy. We show that using a hand-held Raman spectrometer, 100% accurate identification of this species can be performed in only one second. We also demonstrate that in combination with partial least square discriminant analysis (PLS-DA), Raman spectroscopy is capable of distinguishing poison ivy from more than fifteen different plant species, including weeds, grasses and trees. The use of a hand-held spectrometer on a motorized robotic platform or an unmanned aerial vehicle (UAV) can be used for automated surveillance of household and agricultural spaces enabling confirmatory detection and identification of this dangerous plant species.
Prolonged abnormal isolated aminotransferase levels in healthy children is a benign condition.

AIM Hypertransaminasaemia is a common incidental finding in children. It has been demonstrated that even prolonged elevation usually resolves spontaneously without clear aetiology. The aim of this study was to evaluate whether a longer follow-up period, on a larger group, supports the previous findings. METHODS We retrospectively reviewed medical charts of children diagnosed with prolonged idiopathic hypertransaminasaemia, which spontaneously resolved over the follow-up period. RESULTS Of the 468 patients screened for elevated transaminases levels, 87 patients younger than 5 years of age were included in the study. An aetiology was found in half of the patients, and the most common aetiologies were fatty liver and cytomegalovirus (CMV) infection. Aminotransferase abnormality persisted for a median of 10 months, and alanine aminotransferase (ALT) levels ranged from 1.5 to 15.9-fold of the upper limit of normal (ULN). After normalisation of transaminase levels, the values remained normal for a documented mean period of 6.4 ± 3.0 years. CONCLUSION Although idiopathic asymptomatic aminotransferase elevation in healthy children resolves spontaneously in most children, the abnormality may be prolonged. Comprehensive workup finds aetiology only in half of the patients, and the most common aetiologies are fatty liver and CMV hepatitis, which can be diagnosed by non-invasive methods.
Shared requirements for key residues in the antibiotic resistance enzymes ErmC and ErmE suggest a common mode of RNA recognition.

Erythromycin-resistance methyltransferases are SAM dependent Rossmann fold methyltransferases that convert A2058 of 23S rRNA to m62A2058. This modification sterically blocks binding of several classes of antibiotics to 23S rRNA, resulting in a multidrug-resistant phenotype in bacteria expressing the enzyme. ErmC is an erythromycin resistance methyltransferase found in many Gram-positive pathogens, whereas ErmE is found in the soil bacterium that biosynthesizes erythromycin. Whether ErmC and ErmE, which possess only 24% sequence identity, use similar structural elements for rRNA substrate recognition and positioning is not known. To investigate this question, we used structural data from related proteins to guide site-saturation mutagenesis of key residues and characterized selected variants by antibiotic susceptibility testing, single turnover kinetics, and RNA affinity–binding assays. We demonstrate that residues in α4, α5, and the α5-α6 linker are essential for methyltransferase function, including an aromatic residue on α4 that likely forms stacking interactions with the substrate adenosine and basic residues in α5 and the α5-α6 linker that likely mediate conformational rearrangements in the protein and cognate rRNA upon interaction. The functional studies led us to a new structural model for the ErmC or ErmE-rRNA complex.
Legacy effects of non-native Cytisus scoparius in glacial outwash soils: Potential impacts to forest soil productivity in western Washington

Abstract Scotch broom (Cytisus scoparius (L.) Link) is a highly competitive, nonnative, leguminous shrub species of major concern in coast Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii) forests of the Pacific Northwest that has potential to impact long-term soil productivity. We conducted a bioassay to assess the potential for legacy effects on soils (e.g., soil nutrient effects, soil seedbank, etc.) following Scotch broom removal and the potential for recovery over time. The bioassay was conducted using glacial-outwash soils from an existing Long-Term Soil Productivity study near Matlock, WA, USA, where Scotch broom had been removed or kept out for 0 (broom present), 4, 10, or 14 years. Soils from each broom removal duration were combined with fertilizer treatments to assess mechanisms of response of three native plant species: yarrow (Achillea millefolium L.), Roemer’s fescue (Festuca idahoensis Elmer ssp. Roemeri), and coast Douglas-fir. There was evidence for negative soil legacy effects on Douglas-fir growth and biomass, which decreased with time since broom removal. Responses to the fertilizer treatments indicated the effect was not associated with reduced nutrient availability. In contrast, both yarrow and Roemer’s fescue had significantly greater biomass in soil from where broom was recently present, which decreased with time since broom removal. Responses to the fertilizer treatments indicated that this positive legacy effect is associated with nutrient availability, likely increased N. Soils from 0 and 4 years since broom removal were estimated as having the potential to produce over 578,500 Scotch broom germinants ha−1. Our results demonstrate the potential for both negative and positive soil legacy effects of broom depending on the responding plant species. Combined effects of negative soil legacies and a large and viable seed bank from Scotch broom create growing conditions likely to hinder long-term productivity of Douglas-fir.
Oral Flora and Perioperative Antimicrobial Interventions in Cleft Palate Surgery: A Review of the Literature:

Background:The role of perioperative antibiotics in cleft palate remains a topic of debate. Advocates stress their importance in preventing local and systemic infections and decreasing the incidenc...
mSWI/SNF promotes polycomb repression both directly and through genome-wide redistribution

Abstract The mammalian SWI/SNF, or BAF complex, has a conserved and direct role in antagonizing polycomb-mediated repression. Yet, BAF appears to also promote repression by polycomb in stem cells and cancer. How BAF both antagonizes and promotes polycomb-mediated repression remains unknown. Here, we utilize targeted protein degradation to dissect the BAF-polycomb axis in embryonic stem cells on the timescale of hours. We report that rapid BAF depletion redistributes both PRC1 and PRC2 complexes from highly occupied domains, like Hox clusters, to weakly occupied sites that are normally opposed by BAF. Polycomb redistribution from highly repressed domains results in their decompaction, gain of active epigenomic features, and transcriptional derepression. Surprisingly, through dose-dependent degradation of PRC1 & PRC2 we identify both a conventional role for BAF in polycomb-mediated repression and a second mechanism acting by global redistribution of polycomb. These findings provide new mechanistic insight into the highly dynamic state of the Polycomb-Trithorax axis.
Preoperative imaging predicts change in bone mineral density after parathyroidectomy for primary hyperparathyroidism.

Abstract Background Bone Mineral Density (BMD) improves after parathyroidectomy (PTX), but data on factors that predict bone recovery are limited. No studies have evaluated if preoperative imaging findings are associated with postoperative change in BMD. We hypothesized that larger, metabolically active glands would be associated with greater increase in BMD after PTX. Methods Patients with primary hyperparathyroidism (PHPT) who underwent combined Tc-99m sestamibi and 4D-CT imaging prior to PTX and had pre- and post-operative dual-energy X-ray absorptiometry (DXA) at our institution were considered for inclusion. Retrospectively, data were collected from imaging studies on each parathyroid gland, including estimated weight (using the ellipsoid formula) and contrast enhancement on 4D-CT as well as sestamibi avidity. Total estimated parathyroid weight was calculated. The main outcome measure was the percent change in BMD at the lumbar spine (LS) from pre- to post-operative DXA. Predictors of change in BMD at the LS were assessed. Results Complete DXA data was available in 25 patients. Median total parathyroid weight on 4D-CT was 270 mg, and mean change in BMD at the LS was 2.4 ± 4.3%. The increase in BMD was best predicted by higher preoperative serum calcium (p = 0.01), greater estimated parathyroid weight (p = 0.001), sestamibi avidity (p = 0.03), and increased time between DXA scans (p = 0.03) in the multivariable model (R2 = 0.79, p Conclusion In PHPT, higher preoperative serum calcium, parathyroid gland weight on imaging, and sestamibi avidity are associated with greater increases in BMD after curative PTX. These findings suggest that larger, metabolically active adenomas may mobilize more calcium from bone.
Little evidence for genetic variation associated with susceptibility to sea star wasting syndrome in the keystone species Pisaster ochraceus.

The keystone species Pisaster ochraceus suffered mass mortalities along the northeast Pacific Ocean from Sea Star Wasting Syndrome (SSWS) outbreaks in 2013-2016. SSWS causation remains of debate, leading to concerns as to whether outbreaks will continue to impact this species. Considering the apparent link between ocean temperature and SSWS, the future of this species and intertidal communities remains uncertain. Surveys of co-occurring apparently normal and wasting P. ochraceus along the central Oregon coast in 2016 allowed us to address whether variation in disease status showed genetic variation that may be associated with differences in susceptibility to SSWS. We performed restriction site-associated DNA sequencing (2bRAD-seq) to genotype ~72,000 single nucleotide polymorphism (SNP) loci across apparently normal and wasting sea stars. Locus-specific analyses of differentiation (FST ) between disease-status groups revealed no signal of genetic differences separating the two groups. Using a multivariate approach, we observed weak separation between the groups, but identified 18 SNP loci showing highest discriminatory power between the groups and scanned the genome annotation for linked genes. A total of 34 protein-coding genes were found to be located within 15 kb (measured by linkage disequilibrium decay) of at least one of the 18 SNPs, and 30 of these genes had homologies to annotated protein databases. Our results suggest that the likelihood of developing SSWS symptoms does not have a strong genetic basis. The few genomic regions highlighted had only modest levels of differentiation, but the genes associated with these regions may form the basis for functional studies aiming to understand disease progression.
Managing System Effects of Traction Bars Implemented on a Hotchkiss Suspension

This paper describes the implementation effort behind adding a pair of suspension links between the axle and frame of a light truck with a Hotchkiss-type suspension. These links, referred to as anti-windup bars (or traction bars), were introduced into an existing system to improve NVH performance; however, doing so required modifications to maintain other vehicle attributes, including vehicle safety and durability life. The authors address the management of these attributes and related design decisions for the components involved, focusing on the conflicting requirements involved. Physical vehicle testing, using design revisions recommended by Finite Element (FE) simulations, was performed to confirm component performance and related system behavior. Test results suggested improvements to the FE models that were required to more closely approximate the vehicle's behavior. Several of these FE model improvements and component design iterations were implemented simultaneously, resulting in effective anti-windup bar and frame structure design revisions. These design revisions improved the system's ability to manage the energy inputs to the system during vehicle durability and crash testing.
ANTIBIOTIC ACTIVITY OF MYXOBACTERIA IN RELATION TO THEIR BACTERIOLYTIC CAPACITY

Noren, Borge (University of Wisconsin, Madison) and Kenneth B. Raper. Antibiotic activity of myxobacteria in relation to their bacteriolytic capacity. J. Bacteriol. 84: 157–162. 1962— Myxococcus virescens, M. fulvus, M. stipitatus, M. lacteus, Chondrococcus blasticus , and Chondromyces crocatus were tested for antibacterial activity, and all were found to secrete products that inhibited the growth of gram-positive eubacteria. The amount of inhibition varied with the myxobacterium employed and with the eubacterium used as a test organism. The growth of gram-negative eubacteria was in no case visibly affected by the antibiotic products. The experiments performed failed to indicate any positive relationship between the antibacterial activity and the bacteriolytic capacity of the six myxobacteria investigated.
Story-Based Learning: The Impact of Narrative on Learning Experiences and Outcomes

Within the intelligent tutoring systems community, narrative is emerging as an effective medium for contextualizing learning. To date, relatively few empirical studies have been conducted to assess learning in narrative-centered learning environments. In this paper, we investigate the effect of narrative on learning experiences and outcomes. We present results from an experiment conducted with eighth-grade middle school students interacting with a narrative-centered learning environment in the domain of microbiology. The study found that students do exhibit learning gains, that those gains are less than those produced by traditional instructional approaches, but that the motivational benefits of narrative-centered learning with regard to self-efficacy, presence, interest, and perception of control are substantial.
Urban and Regional Dynamics in Poland

In this exploration of urban and regional dynamics in Poland after the transition, the authors find that the degree of urbanization, and primacy remains low in Poland. The largest cities are not growing at the rate that would be expected if post-transition adjustments were operating freely. As a result, Poland is not fully realizing external economies from urban agglomeration. Internal migration decreased significantly in the 1990s, with rural-to-urban migration declining dramatically. Current population levels everywhere seem frozen at a degree of urbanization that is low by international standards. Migration levels do not respond to unemployment differentials, perhaps because Poland's continuing housing shortage, deters migration. Housing construction, which was already low, fell by half in the 1990s, and has only recently begun a slight recovery. A significant number of mostly young, and educated temporary migrants leave Poland annually, many to find employment abroad. This may reduce pressure on the Polish labor market, but also keeps dynamic actors our of the domestic labor force, reducing growth in urban businesses and industry. Employment in manufacturing and agriculture is relatively concentrated, but specialization seems to have declined in recent years, perhaps reflecting barriers to labor mobility - which could limit growth. That employment in the manufacturing sector is quite concentrated, is to be expected in a formerly planned economy. But employment in the service sector, is also quite concentrated. A geographic divergence of service activities is not explained by dominant growth in specialized financial, and business services in the capital alone. Poland's policymakers should find a way to provide housing, thereby reducing barriers to labor mobility, and growth.
A note on convergence in measure

Convergence in measure of a sequence of functions was defined by F.Riesz in 1909. (Cf.[5] and [2] p.177 ff.) It was used to provide a proof of the completeness of L (Riesz-Fischer Theorem). It is also used in the proof of the weak law of large numbers and thus is sometimes called convergence in probability. A sequence of real valued functions {fn} defined on a measure space is said to converge in measure to a function f , written fn → f [meas.], if for every > 0 one has limn→∞m(|fn − f | > ) = 0. Here mE is the measure of E, (f > a) is {x : f(x) > a}, and all functions are presumed measurable and defined on a measure space X. Standard results involving limits in measure can be found in [4]. In particular, convergence in measure does not imply convergence at a single point. However, the limit is unique (up to sets of measure 0); the limit of the sum of two sequences which converge in measure is the sum of the limits in measure; the limit in measure of a constant times the functions in a sequence is the constant times the limit function; and the limit in measure of a sequence of measurable functions is measurable. In Munroe [4] it is proved that if mX <∞ then the limit in measure of the product of two sequences is the product of the limits providing the limits in measure exist. To show that this does not hold on spaces of infinite measure, he gives the example: fn(x) = x and gn(x) = 1/n for each x ∈ (0,∞) where m is Lebesgue measure on the line. However, it is not difficult to show that the limit in measure of the product is the product of the limits under certain conditions. In particular, if the functions f and g are either bounded or Lebesgue integrable and if fn → f [meas.] and gn → g[meas.], then fngn → fg[meas]. Actually, there is a more general condition which guarantees that the limit in measure of the product is the product of the limits in measure. It is given
New York Appellate Division Upholds 'Amazon' Law: Analysis

In Amazon.com LLC et al. v. New York State Department of Taxation and Finance et al., the Appellate Division of the New York Supreme Court upheld and remanded New York’s “Amazon” law. The appeals court correctly held that the New York statute, on its face, comports with the dormant Commerce Clause physical presence nexus test articulated in National Bellas Hess v. Department of Revenue and confirmed in Quill Corporation v. North Dakota. The Appellate Division also correctly held that, on its face, New York’s Amazon law complies with the requirements of Due Process though, on this point, the Appellate Division’s opinion reaches the right result in an unconvincing fashion.On remand to the trial court, of critical import will be the informal administrative construction of New York’s Amazon statute by New York’s Department of Taxation and Finance (“the Department”). The Department concludes that, under the Amazon statute, a New York associate’s unauthorized solicitation activity generates in-state physical presence nexus between New York and the internet seller with which such associate is affiliated. This interpretation of the statute contravenes the dormant Commerce Clause case law of the U.S. Supreme Court and should accordingly be rejected by the New York courts. There is no agency when there is no authority.The constitutionality of New York’s Amazon law does not ensure the law’s wisdom. Indeed, as a matter of tax policy, New York’s Amazon law is unwise. For the long run, New York’s Amazon statute will cost New York more revenue than New York gains as Amazon and other out-of-state internet retailers will respond to the statute by terminating their associates in the Empire State. The best resolution of the problem addressed by New York’s and other states’ Amazon laws is for Congress to legislate pursuant to the Commerce Clause to permit the states to impose sales and use tax enforcement responsibilities on internet (and mail order) sellers regardless of such sellers’ physical presence vel non in the taxing state.
Broadband capacitive sensor CMOS interface circuit for dielectric spectroscopy

A broadband current-mode interface circuit performing capacitive measurements suitable for implementation in CMOS technology is suggested. A capacitance change in the sensor capacitor translates uniformly into a DC voltage change at the output over a broad frequency range (1M/spl sim/1G). This wideband operation enables the performance of broadband dielectric spectroscopy measurements. The circuit has been shown to have a capacitance resolution of 0.7fF and dynamic range of 500fF. It has been designed in 0.18/spl mu/m CMOS technology and consumes 10.46mW of power at a power supply of +/-1 V.
From the sidelines: coaching as a nurse practitioner strategy for improving health outcomes.

Purpose: The purposes of this study were to explore coaching as a nurse practitioner (NP) strategy for improving patient health outcomes and to lay a foundation for validating coaching benefits. Data sources: Review of coaching literature in psychology, sports, business, and nursing. Conclusions: Coaching has been reported as successful in psychology, sports, business, and more recently nursing, for assisting people to achieve goals that are important to them. Coaching may be very effective in encouraging, inspiring, and empowering patients to reach their maximum health potential, particularly if lifestyle change is required; however, coaching research is in its early stages. Coaching is not well defined, so claims of coaching benefits must be viewed cautiously. Coaching is an expected NP role competency, but it is not well explicated in the literature. Defining the concept of coaching from multidisciplinary consensus, expanding knowledge of the coaching process, and consciously implementing coaching communication in the NP/patient primary care encounter may result in measurable outcomes that demonstrate coaching effectiveness. Implications for practice: Coaching fits well with the holistic, collaborative approach to patient care which NPs value. Coaching provides an opportunity to shift traditional thinking about patient/provider relationships and how to motivate patients toward behavior change. The challenge for NPs is to take the time to learn the coaching process, employ coaching communication strategies in the primary care encounter, and engage in research that measures coaching effectiveness.
Modeling leiomyosarcoma in the mouse

Proc Amer Assoc Cancer Res, Volume 47, 2006 4848 Sarcomas are a family of tumors of mesenchymal origin representing <1% of all human cancers. A subgroup of soft-tissue sarcomas is associated to defined chromosomal translocations and simple karyotypes, whereas the rest (including leiomyosarcomas) is characterized by complex genotypes and numerous chromosomal aberrations. To date, both the underlying genetic defects and the cell of origin of most human sarcomas remain unknown. Recently, alterations in the PI3K-Akt pathway have been identified in certain sarcoma subtypes. For instance, loss of heterozygosity of 10q23 (containing the PTEN genomic locus) has been frequently observed in human leiomyosarcomas. To determine the role of aberrant PI3K-Akt signaling in leiomyosarcoma pathogenesis, we have genetically inactivated PTEN in the smooth muscle lineage by crossing PTENlox/lox and SM22α-cre mice. Resultant animals carrying homozygous deletion of both PTEN alleles developed widespread smooth muscle hyperplasia, particularly affecting the urinary tract and the intestinal wall. Furthermore, we observed a very rapid onset (2-3 months of age) and elevated incidence of abdominal leiomyosarcomas. Importantly, some of them originate from the blood vessel walls, consistent with one of the sites of origin of these tumors in humans. We confirmed the smooth-muscle origin of these lesions by positive staining of well-established markers, such as desmin and smooth muscle actin. As expected, tumors display high levels of p-Akt and downstream effectors, indicative of constitutive Akt-mTOR signaling. In addition, we found a significant induction of p53 expression, confirming the p53-mediated anti-proliferative response subsequent to PTEN inactivation found in other tissue types. Taken together, our data reveal a novel critical role for the PTEN-Akt pathway in mesenchymal transformation and sarcomagenesis. These newly generated sarcoma models may enable the identification of secondary genetic or phenotypic events required for sarcoma progression and/or metastasis. Finally, we are currently performing pre-clinical studies in this model with new therapeutic compounds that target the Akt-mTOR pathway.
Divine hiddenness as divine mercy

If God exists, why isn't His existence more apparent? In recent analytic philosophy this longstanding question has been developed into an argument for atheism typically referred to as the ‘problem of divine hiddenness’. My goal here is to put forward a new reply. The basic idea is that there is some reason to think that for many of us, our moral conduct would not improve even if God's existence were not subject to doubt. However, immoral conduct in such a state of affairs would be even more immoral, and hence justly subject to greater punishment, than it is in a state of affairs in which God's existence is subject to doubt. As such, God mercifully remains ‘hidden’ in order to limit our moral culpability.
New nanofabrication technique using overlay for 15-nm zone plate

Soft x-ray zone plate microscopy has proven to be a valuable imaging technique for nanoscale studies. It complements nano-analytic techniques such as electron and scanning probe microscopies, and offers a unique set of capabilities including high spatial resolution, natural elemental/chemical and magnetic sensitivities, large permissible sample thickness, and a myriad of in-situ sample environments. In this paper, a new zone plate fabrication technique based on overlaying complementary, semi-dense patterns is described. The new technique permits zone plates with sub-20 nm zones, which are extremely challenging for conventional fabrication processes, to be fabricated. With the new technique, zone plates of 15 nm outermost zone width were successfully fabricated for the first time, yielding a spatial resolution better than 15 nm. Zone plates of 10 nm outer zones, as well as 3-D zone plate structures, which cannot be fabricated using conventional zone plate fabrication processes, are anticipated with the overlay technique.
Frustration, Training, and Task Complexity in Rats

A double alley followed by a linear maze was used to determine whether frustration, elicited by reward quality reduction, would impair maze performance (complex task) when response strength was weak and would facilitate performance when response strength was high. For this purpose one group of rats (n = 11) was given maze training with only the correct door unlocked at each choice point (those used under frustration conditions), whereas, the second group (n = 11) was trained with all doors at each choice point unlocked. On subsequent test trials, frustration enhanced run speeds in the double alley but had no significant effect on maze errors irrespective of level of training. The results were discussed within Spence's motivation-performance hypothesis and Amsel's frustration theory.
Analysis of rat lymphocyte activation of benzo[a]pyrene, 2-acetylaminofluorene, and several of their metabolites to mutagenic and DNA-damaging species in vitro.

Rat lymphocytes are a potentially useful and convenient cell system for monitoring the genotoxic effects of chemicals in vivo, but little is known about the ability of these cells to metabolize promutagens to genotoxic species. In this study, Fischer 344 rat lymphocytes were treated in vitro with benzo[a]pyrene (BaP), 2-acetylaminofluorene (2-AAF), and several of their metabolites, and DNA damage was measured using nucleoid sedimentation analysis. Of the BaP derivatives, BaP 4,5-oxide and BaP 7,8-diol-9, 10-epoxide decreased lymphocyte nucleoid sedimentation, whereas BaP and BaP 7,8-dihydrodiol had little effect. Among the 2-AAF derivatives, N-acetoxy-2-AAF, N-hydroxy-2-AAF, and N-hydroxy-2-aminofluorene damaged rat lymphocyte nucleoids, whereas 2-AAF, 2-aminofluorene, and fluorene produced little detectable damage. The decrease in nucleoid sedimentation produced by N-hydroxy-2-AAF was not inhibited by paraoxon, salicylamide, or 2-aminofluorene, whereas paraoxon inhibited damage produced by N-acetoxy-2-AAF. In co-culture assays, rat lymphocytes increased the mutagenicity of N-hydroxy-2-AAF in Salmonella typhimurium strain TA98, but mediated little or no mutagenic response with BaP, BaP 7,8-dihydrodiol, and 2-AAF. Also, human lymphocytes, but not rat lymphocytes, mediated a positive mutagenic response with BaP 7,8-dihydrodiol in Chinese hamster ovary UV5 cells. Although rat lymphocytes may metabolize certain proximal genotoxic chemicals to DNA-damaging species (e.g., N-hydroxy-2-AAF), these data suggest that in vivo lymphocyte DNA damage is more likely to result from lymphocytes encountering reactive chemical derivatives produced by other cells. It is also clear that differences exist between the ability of human and rat lymphocytes to activate promutagens, and this may impact on the use of the rat model to predict the genotoxicity of chemicals in humans.
The efficacy of the ketogenic diet - 1998: A prospective evaluation of intervention in 150 children

Objective. The ketogenic diet is a high-fat, low-protein, low-carbohydrate diet developed in the 1920s for the treatment of children with difficult to control seizures. Despite advances in both the pharmacotherapy and the surgery of epilepsy, many children continue to have difficult-to-control seizures. This prospective study sought to determine the ketogenic diet9s effectiveness and tolerability in children refractory to today9s medications. Methods. One hundred fifty consecutive children, ages 1 to 16 years, virtually all of whom continued to have more than two seizures per week despite adequate therapy with at least two anticonvulsant medications, were prospectively enrolled in this study, treated with the ketogenic diet, and followed for a minimum of 1 year. Seizure frequency was tabulated from patients9 daily seizure calendars and seizure reduction calculated as percentage of baseline frequency. Adverse events and reasons for diet discontinuation were recorded. Results. The children (mean age, 5.3 years), averaged 410 seizures per month before the diet, despite an exposure to a mean of 6.2 antiepileptic medications. Three months after diet initiation, 83% of those starting remained on the diet and 34% had >90% decrease in seizures. At 6 months, 71% still remained on the diet and 32% had a >90% decrease in seizures. At 1 year, 55% remained on the diet and 27% had a >90% decrease in seizure frequency. Most of those discontinuing the diet did so because it was either insufficiently effective or too restrictive. Seven percent stopped because of intercurrent illness. Conclusions. The ketogenic diet should be considered as alternative therapy for children with difficult-to-control seizures. It is more effective than many of the new anticonvulsant medications and is well tolerated by children and families when it is effective.
Transport properties and a current-functional theory in the linear-response regime.

The possibility of formulating a time-dependent current-functionsl theory which describes the linear responses of systems of inhomogeneous, interacting electron gas to an arbitrary form of time-dependent electromagnetic field is studied. A Kohn-Sham--type theory for the dynamical electronic conductivity tensor is derived and a local-density type of approximation for the resulting exchange-correlation electric field is constructed.
High-resolution genetic mapping of the sucrose octaacetate taste aversion (Soa) locus on mouse Chromosome 6

An acetylated sugar, sucrose octaacetate (SOA), tastes bitter to humans and has an aversive taste to at least some mice and other animals. In mice, taste aversion to SOA depends on allelic variation of a single locus, Soa. Three Soa alleles determine `taster' (Soaa), `nontaster' (Soab), and `demitaster' (Soac) phenotypes of taste sensitivity to SOA. Although Soa has been mapped to distal Chromosome (Chr) 6, the limits of the Soa region have not been defined. In this study, mice from congenic strains SW.B6-Soab, B6.SW-Soaa, and C3.SW-Soaa/c and from an outbred CFW strain were genotyped with polymorphic markers on Chr 6. In the congenic strains, the limits of introgressed donor fragments were determined. In the outbred mice, linkage disequilibrium and haplotype analyses were conducted. Positions of the markers were further resolved by using radiation hybrid mapping. The results show that the Soa locus is contained in a ∼1-cM (3.3–4.9 Mb) region including the Prp locus.
Nonlinear Flight Control Using Forebody Tangential Blowing

A novel nonlinear approach is presented to designing aircraft control laws based on combining high-gain control and Lyapunov techniques. The approach is applied and demonstrated experimentally to control the lateraldirectional dynamics of an aircraft at high angle of attack using forebody tangential blowing (FTB). FTB is a pneumatic device that modie es the vortical e ow over the forebody. The modie ed vortical e ow in turn creates roll and yaw moments for control characterized by highly nonlinear and uncertain input/output characteristics. The control approach presented here robustly inverts these characteristics and enables the exploitation of the full FTB efe ciency. The control approach is applicable in general to nonlinear systems which are actuated by a subsystem comprising uncertain static nonlinearities and linear dynamics.
Voices in flight: Integrating movement/dance with poetry therapy

This brief report includes an introduction to several movement techniques that can be integrated with Mazza's (2003) multidimensional model of poetry therapy
Dissolved oxygen quenching of in—situ fluorescence measurements

summary, a twice—frequencydoubled Nd:YAG laser is used as a fluorescence excitation source. Its266 nm light is carried to the location of interest, such as in aground water monitoring well, by a fiber optic. Another fiber opticcarries any resulting fluorescence back to the instrument whereanalysis of fluorescence wavelength, intensity, and/or lifetime can byused to determine the nature and concentration of aromatic organiccontaminants present.Our second LIF prototype was constructed to be smaller than thefirst one, and in modules for ease of handling. The optical table isshock mounted and sealed in a weatherproof box. The sensor is lessthan 3/4 inch in diameter and fits virtually any monitoring well. Thedetector module occupies a second smaller box, while power supplies andinterface electronics are mounted in a third container. A portable PC,used as instrument controller and data logger, completes theinstrumentation. Each of the pieces weigh fifty pounds or less and allfit in a rented minivan or station wagon.Benzene, toluene, ethylbenzene, and xylenes (BTEX) are commonground water contaminants arising from crude petroleum and fuels.Since they fluoresce when excited by ultraviolet light, suchfluorescence may be used for identification and quantification. Atypical sampling round involved our bringing the unit to a site withinstalled wells and a history of arornatics contamination, typically bygasoline or aromatic solvents. Electrical power for the instrument was
Cylindrical sound wave generated by shock-vortex interaction

The passage of a columnar vortex broadside through a shock is investigated. This has been suggested as a crude, but deterministic, model of the generation of 'shock noise' by the turbulence in supersonic jets. The vortex is decomposed by Fourier transform into plane sinusoidal shear waves disposed with radial symmetry. The plane sound waves produced by each shear wave/shock interaction are recombined in the Fourier integral. The waves possess an envelope that is essentially a growing cylindrical sound wave centered at the transmitted vortex. The pressure jump across the nominal radius R = ct attenuates with time as 1/(square root of R) and varies around the arc in an antisymmetric fashion resembling a quadrupole field. Very good agreement, except near the shock, is found with the antisymmetric component of reported interferometric measurements in a shock tube. Beyond the front r approximately equals R is a precursor of opposite sign, that decays like 1/R, generated by the 1/r potential flow around the vortex core. The present work is essentially an extension and update of an early approximate study at M = 1.25. It covers the range (R/core radius) = 10, 100, 1000, and 10,000 for M = 1.25 and (in part) for M = 1.29 and, for fixed (R/core radius) = 1000, the range M = 1.01 to infinity.
Escherichia coli growth and transport in the presence of nanosilver under variable growth conditions.

Nanosilver (silver nanoparticles) has the ability to anchor to the bacterial cell membrane and subsequently penetrate it, thereby causing structural changes (i.e. permeability) in the cell membrane and death of the cell. The bacterial responses to the presence of nanosilver usually vary depending on the concentration of nanosilver particles, exposure time and the bacterial physiological stage. Since bacterial anabolism dependents upon a stoichiometric ratio of carbon and inorganic elements (nutrients), the macronutrient ratio, i.e. carbon to nitrogen ratio (C/N) thus plays an important role of bacterial responses to the exposure of nanosilver. This study investigated the responses of Escherichia coli to the exposure of nanosilver under variable growth conditions. It was discovered that E. coli grown under different growth conditions had different responses to the presence of nanosilver. E. coli had least resistance to the toxicity of nanosilver when cultured under carbon-limited conditions. However, the p...
Health reform and cesarean sections in the private sector: The experience of Peru

Abstract Objectives : To test the hypothesis that the health reform enacted in Peru in 1997 increased the rate of cesarean sections in the private sector due to non-clinical factors. Methods : Different rounds of the Demographic and Health Survey are used to estimate determinants of c-section rates in private and public facilities before and after the healthcare reform. Estimations are based on a pooled linear regression controlling by obstetric and socioeconomic characteristics. Results : C-section rates in the private sector grew from 28 to 53% after the health reform. Compared to the Ministry of Health (MOH), giving birth in a private hospital in the post-reform period adds 19% to the probability of c-section. Conclusions : The health reform implemented in the private sector increased physician incentives to over-utilize c-sections. The reform consolidated and raised the market power of private health insurers, but at the same time did not provide mechanisms to enlarge, regulate and disclose information of private providers. All these factors created the conditions for fee-for-service paid providers to perform more c-sections. Comparable trends in c-section rates have been observed in Latin American countries who implemented similar reforms in their private sector, suggesting a need to rethink the role of private health providers in developing countries.
Self-oscillatory behavior of ionic polymer-metal composite (IPMC): a new finding

In this paper, we present a fascinating new feature of Ionic Polymer-Metal Composite (IPMC), "self-oscillation." In the presence of Small Organic Molecules (SOMs) in an aqueous medium, the self-oscillatory and periodic deformation of IPMCs was evident. The oscillations are caused by the potential periodicity in the Pt anode where the activation-overpotential is altered by complex surface reactions under an applied DC current. Such a self-oscillatory behavior of IPMC was highly conceivable and repeatable when it was properly prepared. The importance of surface reactions can be acknowledged when the potential intermediates, such as PtOH, PtO, and PtCO are believed to exist. The oscillatory potential was obtained by properly alternating the presence and the absence of CO molecules on the anode at a constant current.
Preconception Brief: Occupational/Environmental Exposures

In the last decade, more than half of U.S. children were born to working mothers and 65% of working men and women were of reproductive age. In 2004 more than 28 million women age 18–44 were employed full time. This implies the need for clinicians to possess an awareness about the impact of work on the health of their patients and their future offspring. Most chemicals in the workplace have not been evaluated for reproductive toxicity, and where exposure limits do exist, they were generally not designed to mitigate reproductive risk. Therefore, many toxicants with unambiguous reproductive and developmental effects are still in regular commercial or therapeutic use and thus present exposure potential to workers. Examples of these include heavy metals, (lead, cadmium), organic solvents (glycol ethers, percholoroethylene), pesticides and herbicides (ethylene dibromide) and sterilants, anesthetic gases and anti-cancer drugs used in healthcare. Surprisingly, many of these reproductive toxicants are well represented in traditional employment sectors of women, such as healthcare and cosmetology. Environmental exposures also figure prominently in evaluating a woman’s health risk and that to a pregnancy. Food and water quality and pesticide and solvent usage are increasingly topics raised by women and men contemplating pregnancy. The microenvironment of a woman, such as her choices of hobbies and leisure time activities also come into play. Caregivers must be aware of their patients’ potential environmental and workplace exposures and weigh any risk of exposure in the context of the time-dependent window of reproductive susceptibility. This will allow informed decision-making about the need for changes in behavior, diet, hobbies or the need for added protections on the job or alternative duty assignment. Examples of such environmental and occupational history elements will be presented together with counseling strategies for the clinician.
The mixed alkali effect in zinc-compensated (K,Na)-β-gallate

Abstract The “mixed alkali effect” was investigated in a Zn-doped K-β-gallate fast ion conductor with partial replacement of the K by Na. A minimum in conductivity occurs at about 0.8 atom fraction Na. A model is proposed in which the site occupancies are determined by the interstitial pair concept, and the conductivity minimum occurs when Beevers-Ross sites are occupied by K+ only. A knee in the Arrhenius plots of samples containing potassium is explained as the onset of activation of K+ away from interstitial complexes bound coulombically to the zinc charge-compensating centers.