cssi/SciSciGPT-SciSciNet huggingface dataset:
Yeast 2-micrometer plasmid DNA replication in vitro: origin and direction

Abstract Most yeast strains harbor extrachromosomal 2-micrometer DNA, and this DNA synthesis, like nuclear DNA replication, is strictly under cell cycle control. A soluble extract of yeast Saccharomyces cerevisiae carries out semiconservative replication of added 2-micrometer DNA and Escherichia coli chimeric plasmids containing the 2-micrometer DNA. Replication is initiated on 10% of the DNA, and one round of replication is completed. The major products in early stages of replication are theta ("eye") forms which originate 140 +/- 50 nucleotides within one of the 599-base-pair inverted repeats of 2-micrometer DNA. Their replication is bidirectional and discontinuous. Extracts prepared from the cell division cycle mutant cdc8 show temperature-sensitive 2-micrometer DNA synthesis in vitro, suggesting that this in vitro system resembles in vivo 2-micrometer plasmid DNA replication. This system should provide a useful assay for the purification and characterization of yeast DNA replication proteins.
Investigation of the level density parameter using evaporative α -particle spectra from the 19 F + 181 Ta reaction

Light charged particles in coincidence with evaporation residues from the ${}^{19}\mathrm{F}{+}^{181}{\stackrel{\ensuremath{\rightarrow}}{\mathrm{Ta}}}^{200}\mathrm{Pb}$ reaction have been studied at ${E}_{\mathrm{lab}}=121,$ 154, 179, and 195 MeV with the aim of determining, within the context of the statistical model, a possible dependence of the Fermi-gas level density parameter on the temperature/excitation energy of the emitting system. Angular distributions of evaporation residues and of fission fragments, along with fission fragment folding angle distributions, were also measured. A moderate excitation energy dependence of the level density parameter, as given by recent theoretical calculations, is consistent with the measured $\ensuremath{\alpha}$-particle spectral shapes. Although the spectra are reproduced best with a weakly varying level density parameter, a constant level density parameter of a=A/12 ${\mathrm{MeV}}^{\ensuremath{-}1}$ cannot be excluded.
Effects of chronic treatment with cadmium on ATPases, uptake of catecholamines, and lipid peroxidation in rat brain synaptosomes☆

Abstract The chronic effects of cadmium on specific activities of oligomycin-sensitive (OS) and -insensitive Mg2+ ATPase, Na+K+ ATPase, lipid peroxidation, and uptake of catecholamines in brain synaptosomes of rats treated daily for 2 or 4 months were studied. Cadmium significantly decreased the specific activities of OS-Mg2+ ATPase, Na+K+ ATPase, and uptake of [3H]-dopamine (3H-DA) and [3H]norepinephrine (3H-NE) and increased the lipid peroxidation.
Trans-generational parasite protection associated with paternal diet

Multiple generations of hosts are often exposed to the same pathogens, favouring the evolution of trans-generational defences. Because females have more opportunities to transfer protective molecules to offspring, many studies have focused on maternally derived protection. However, males of many species can transfer compounds along with sperm, including chemicals that could provide protection. Here, we assess maternally and paternally derived protection in a monarch butterfly-protozoan parasite system where parasite resistance is heavily influenced by secondary plant chemicals, known as cardenolides, present in the larval diet of milkweed plants. We reared monarch butterflies on medicinal and non-medicinal milkweed species and then measured resistance of their offspring to infection. We also measured cardenolide content in adult monarchs reared on the two species, and in the eggs that they produced. We found that offspring were more resistant to infection when their fathers were reared on medicinal milkweed, while maternal diet had less of an effect. We also found that eggs contained the highest levels of cardenolides when both parents were reared on the medicinal species. Moreover, females reared on non-medicinal milkweed produced eggs with significantly higher levels of cardenolides if they mated with males reared on the medicinal milkweed species. However, we found an equivocal relationship between the cardenolides present in eggs and parasite resistance in the offspring. Our results demonstrate that males reared on medicinal plants can transfer protection to their offspring, but the exact mechanism remains unresolved. This suggests that paternal protection from parasitism might be important, particularly when there are environmental sources of parasite resistance and when males transfer spermatophores during mating.
Is fibromyalgia an endocrine/endorphin deficit disorder? Is low dose naltrexone a new treatment option?

Fibromyalgia is a chronic pain syndrome. Neuman and Buskila noted that fibromyalgia afflicts approximately 5% of women and 1.6% of men. The diagnosis of fibromyalgia is primarily based on chronic widespread pain that has (1) pain on both sides of the body, (2) is above and below the waist, (3) should involve the axial skeleton, and (4) must have been present for more than 3 months. Physical examination must include at least 11 of 18 tender points. In clinical practice, nearly half the population may have fewer tender points. A new proposed fibromyalgia syndrome also includes sleep deficits, daytime fatigue, and altered cognition/mood as a part of the syndrome. Comorbid psychiatric disorders are common in fibromyalgia. Arnold et al. reported that 75% of patients with fibromyalgia have a mood disorder, 60% have an anxiety disorder, and 26% have a substance use disorder. A clearly defined causative explanation for fibromyalgia has eluded investigators. One of the earliest explanations for fibromyalgia looked at the most obvious source—muscle. However, this theory was disproved quickly, leading to more central explanations. The two most accepted evidence-based theories include: neuropeptide abnormalities (involving entities such as Substance P, serotonin, and endogenous opioids); and neuroendocrine defects (including the hypothalamo-pituitary adrenal [HPA], hypothalamo-pituitary gonadal [HPG], hypothalamo-pituitary-thyroid, and the growth hormone axes). Endorphins play a significant role in pain perception. Hence, it is not surprising that a number of investigators have looked at perturbations of endorphin function as a possible explanation for fibromyalgia. Vaeroy et al. observed that CSF -endorphin levels are either normal or lowered in individuals with fibromyalgia. The authors concluded that other endogenous opioids (such as proenkephalin and prodynorphin) may
Mg II Emission Lines of Hyades F Stars

With the Hubble Space Telescope (HST) we have observed Hyades F stars, using the Space Telescope Imaging Spectrograph (STIS), in order to get more information about the heating mechanism(s) for the chromospheres and transition layers and their dependence on rotation and age. In this paper we study the Mg II lines at 2800 A. We include earlier observations with the International Ultraviolet Explorer (IUE) satellite. The Mg II emission lines become observable for B - V > 0.3. The emission line fluxes increase steeply until B - V ~ 0.40. For single stars there is a steep decrease in flux between B - V = 0.41 and B - V = 0.44, similar to the behavior of the Ca II emission line cores. For larger B - V the Mg II emission line fluxes again increase, but much more slowly than for the Ca II lines. Generally, the low point of the emission is reached between B - V = 0.43 and B - V = 0.45, i.e., similar to the Ca II emission cores. For the Hyades F stars there appears to be a difference between the emissions for single stars and those for binaries. We find that for Hyades stars with surface line fluxes larger than 106 ergs cm-2 s-1 the emission line fluxes decrease with increasing v sin i. For smaller fluxes they may increase with increasing v sin i. We have only three stars that perhaps show this. We study the flux ratios of the Mg II k and h lines at 2795.7 and 2802.5 A in order to determine where the lines fall on the curve of growth. For the earliest F stars studied here the ratio is close to 2, as expected for optically thin lines. Generally, it seems that the optical depths in the line centers are less than 10. There remain problems in understanding the size of the line widths. We discuss the interpretation of the Wilson-Bappu effect. For the Hyades F stars there is a strong dependence of the line width on the effective temperature.
Manufacturing for design: a novel interconnect optimization method

Disconnection between design and manufacturing has become a prevalent issue in modern VLSI processes. As manufacturability becomes a major concern, uncertainties from process variation and complicated rules have increased the design cost exponentially. Numerous design methodologies for manufacturability have been proposed to improve the yield. In deep submicron designs, optical proximity correction (OPC) and fill insertion have become indispensable for chip fabrication. In this paper, we propose a novel method to use these manufacturing techniques to optimize the design. We can effectively implement non-uniform wire sizing and achieve substantial performance and power improvement with very low costs on both design and manufacturing sides. The proposed method can reduce up to 42% power consumption without any delay penalty. It brings minor changes to the current design flow and no extra cost for fabrication.
The conformations of poly(butylene-terephthalate) and poly(butylene-2,6-naphthalate) chains in their α and β crystalline polymorphs

Abstract Both thermoplastic polyesters, poly(butylene-terephthalate) (PBT) and poly(butylene-2,6-naphthalate) (PBN), have been observed to undergo solid–solid phase transitions between α and β crystalline polymorphs. Fiber repeat distances determined by X-ray diffraction in the β polymorphs of PBT and PBN are larger than those observed in their α polymorphs. This has generally been attributed to an extension of the butylene glycol portion of both polyesters, where the O–CH 2 –↷ ϕ –CH 2 –CH 2 and (CO)–O–↷ ψ –CH 2 –CH 2 bonds are transformed from ϕ = G to S and ψ = G to T or S to T conformations, respectively, when PBT or PBN transform from their α to their β polymorphs. However, this interpretation is not consistent with solid-state 13 C NMR observations made on the α and β crystalline forms of PBT and PBN. In both instances, only very small differences (0.4–0.8 ppm) in the resonance frequencies of the butylene carbon resonances are observed between the 13 C NMR spectra recorded for both polymorphs. Similar small differences in the aromatic carbon resonance frequencies are observed between their α and β polymorphs. Thus, we conclude that the extension of both PBT and PBN chains, as they are transformed from their α to their β crystalline polymorphs, is more likely a consequence of an increase in the coplanarity of their ester groups and their phenyl or naphthyl rings, rather than conformational extensions of their butylene glycol fragments. A search for PBT and PBN conformations, both of which match the fiber repeat distances observed for their α and β crystalline polymorphs and are consistent with the closely similar 13 C chemical shifts observed in both of their crystalline phases, lends further support to this suggestion.
The Location of DNA in RecA-DNA Helical Filaments

The helical filament that the RecA protein of Escherichia coli forms around DNA is the active apparatus in protein-catalyzed homologous genetic recombination. The actual position of DNA within this complex has been unknown. Image analysis has been performed on electron micrographs of filaments of RecA on double-stranded DNA and on single-stranded DNA to visualize a difference that is consistent with one strand of the double-stranded DNA. This localization of the DNA gives additional information about the unusual structure of DNA in the complex with RecA protein.
Cephalosporin Induced Toxic Epidermal Necrolysis and Subsequent Penicillin Drug Exanthem

ABSTRACT Background Drug hypersensitivity is classically divided into IgE mediated and non-IgE mediated disease. We report a rare case of consequent IgE mediated and non-IgE mediated reactions within the beta lactam class of antibiotics. Case Summary An 84-year-old man developed toxic epidermal necrolysis (TEN) due to ceftriaxone, a third generation cephalosporin, involving 72% of the body surface area. The patient recovered but within weeks subsequently developed an acute IgE mediated allergic reaction to piperacillin/tazobactam, an extended spectrum penicillin. Further IgE RAST revealed positive results to penicillin major determinant. Discussion This case demonstrates the complexity of drug hypersensitivity reactions. While it is accepted that IgE mediated penicillin allergy is a predisposition to cephalosporin allergy, this case displays an unusual correlation between drug hypersensitivity and drug class. There have been few studies that evaluate the cross reactivity with penicillin or other beta-lactams in subjects with primary hypersensitivity to cephalosporins. This clinical scenario emphasizes the need of more studies on cephalosporin allergy in particular as shown by this case of sequential non-IgE mediated cephalosporin induced TEN reaction pursuant by an IgE mediated penicillin allergy.
The Origin of Regioselectivity in 2‐Butanol Dehydration on Solid Acid Catalysts

The origin in the variations of trans-/cis-2-butene product selectivity ratios in 2-butanol dehydration over solid acid catalysts were investigated using a combined experimental-theory approach. Reactivity measurements over γ-Al2O3, AlOx/SBA-15, and H-form zeolites with widely varying Si/Al ratios and pore structures showed over two orders of magnitude change in the trans-/cis-2-butene product ratio. Activation energy barriers calculated for the concerted C-O and β-C-H bond breakings of adsorbed butoxy intermediates by dispersion-corrected DFT calculations correctly predicted the trans-/cis-2-butene product ratio observed on γ-Al2O3. The very low trans-2-butene selectivity on γ-Al2O3 can now be understood by the formation of a late transition state with high energy barrier caused by the strong van der Waals interaction between the γ-H atoms and the flat catalyst surface. Decreasing the dispersive attractive force between the adsorbed butoxide and the surface (e.g., by moving it further away from the support surface in AlOx/SBA-15) leads to almost equimolar formation of the trans- and cis-2-butene isomers. Trans-/cis-2-butene selectivity ratios much higher than that dictated by thermodynamic equilibrium can be achieved by introducing additional geometric constraints around the active catalytic site (e.g., varying the 3D environment around the active center in zeolites). We propose a model to explain the widely varyingmore » trans-/cis-2-butene selectivity in 2-butanol dehydration over solid acid catalysts that is consistent with the experimental results in this study. A key outcome of the study is the realization that van der Waals interactions between the reactant and the active catalyst surface must be included in the theoretic models in order to be able to accurately predict product selectivities. This information, in turn, significantly advances our ability to develop catalyst materials with designed active centers in order to achieve desired regioselectivities.« less
Immunosuppression for pancreatic islet transplantation

Protocols for islet transplantation have to take into account the diabetogenicity/islet toxicity of the immunosuppressive agents, namely corticosteroids and calcineurin inhibitors, most notably tacrolimus. The development by the Edmonton group of a sirolimus-based, steroid-free, low-tacrolimus regimen was a significant breakthrough that allowed the rate of insulin independence after islet transplantation to increase from 13% to 80% at 1 year. Drawbacks include the side effects of sirolimus and the reduction in insulin independence to 50% at 3 years, the latter being attributed to prolonged tacrolimus exposure. Currently explored alternatives to tacrolimus include cyclosporine, mycophenolate mofetil, and the novel agent FTY 720. Perspectives for the near future involve the achievement of "prope tolerance" by strategies using lymphocyte-depleting antibodies (anti-thymocyte globulin, campath-1H, hOKT3gamma1 [ala,ala]), or costimulatory blockade (anti-CD154 mAbs, CTLA4-Ig).
Hybrid fixation tibial prosthesis: Early clinical and radiographic results and retrieval analysis

A prosthetic tibial component has been designed with features for fixation to bone using a combination of acrylic cement and ingrowth interfaces. This hybrid concept affords the component the immediate stability of cement fixation and the potential long-term stability of biologic fixation. The ingrowth interfaces (coupled with the central stem) are intended to shield the cement interface beneath the tibial tray from the tensile liftoff forces that result from eccentric loading, while avoiding the fretting and osteolysis associated with screw fixation. A disassembly capability allows the tray to be removed from the stemmed anchorage assembly, facilitating component extraction and limiting bone loss. A clinical and radiographic review of 50 consecutive primary total knee arthroplasties with a mean follow-up period of 35 months revealed stable interfaces with no progressive radiolucencies and minimal remodeling changes. The mean Knee Society knee score was 92.2. At final follow-up evaluation, 88.6% of patients noted no or mild (occasional) pain. Retrieval of three prosthetic knees with chronic sepsis showed extensive ingrowth into the porous interfaces and an osteointegrated bony sleave around the smooth central stem.
Cation channel control of neurite morphology.

Abstract The development of neuronal polarity and morphology is essential for a functioning nervous system. The present study was undertaken to explore whether blockade of specific channels alter neuronal morphology. Retinal ganglion cells were cultured in the presence of antagonists to NMDA, AMPA/kainate, L-, N-, P-, and Q-type voltage-dependent calcium channels (VDCCs). Five parameters were measured under these conditions: the number of neurites at the cell body, total neurite length, the length of the longest neurite, the number of branch points per neurite, and the diameter of the cell soma. Antagonists to NMDA and L-type VDCCs reduce the number of neurites at the cell body; antagonists to P- and Q-type VDCCs increase the number of neurites. Antagonists to the N-type VDCCs increase total neurite outgrowth, while antagonists to the NMDA and P-type channels reduce total neurite length. Antagonists to the NMDA and L-type channels increase the length of a single neurite, while decreasing the number of branch points; antagonists to the P- and Q-type VDCCs do essentially the opposite—increase the number of neurites, while decreasing the length of each. Blockade of one or more cation channels in developing retinal ganglion cells significantly perturbs neurite morphology. This study may help elucidate part of the role that cation channel signaling plays in neuritic development.
Factors Predicting Response to a Complementary Medicine Treatment Programme for Uterine Fibroids

Background: A previous study showed that fibroids shrank or disappeared for some women who used a suite of complementary therapies. The current study asked what differed among women who benefited from those who did not.
The Nevada Rural Ozone Initiative (NVROI): Insights to understanding air pollution in complex terrain

The Nevada Rural Ozone Initiative (NVROI) was established to better understand O3 concentrations in the Western United States (US). The major working hypothesis for development of the sampling network was that the sources of O3 to Nevada are regional and global. Within the framework of this overarching hypothesis, we specifically address two conceptual meteorological hypotheses: (1) The high elevation, complex terrain, and deep convective mixing that characterize Nevada, make this state ideally located to intercept polluted parcels of air transported into the US from the free troposphere; and (2) site specific terrain features will influence O3 concentrations observed at surface sites. Here, the impact of complex terrain and site location on observations are discussed. Data collected in Nevada at 6 sites (1385 to 2082 m above sea level (asl)) are compared with that collected at high elevation sites in Yosemite National Park and the White Mountains, California. Average daily maximum 1-hour concentrations of O3 during the first year of the NVROI ranged from 58 to 69 ppbv (spring), 53 to 62 ppbv (summer), 44 to 49 ppbv (fall), and 37 to 45 ppbv (winter). These were similar to those measured at 3 sites in Yosemite National Park (2022 to 3031 m asl), and at 4 sites in the White Mountains (1237 to 4342 m asl) (58 to 67 ppbv (summer) and 47 to 58 ppbv (fall)). Results show, that in complex terrain, collection of data should occur at high and low elevation sites to capture surface impacts, and site location with respect to topography should be considered. Additionally, concentrations measured are above the threshold reported for causing a reduction in growth and visible injury for plants (40 ppbv), and sustained exposure at high elevation locations in the Western USA may be detrimental for ecosystems.
Transdiagnostic Cognitive–Behavioral Group Therapy for Anxiety: Outcome and Process

Much has been written about the applicability of cognitive–behavioral group treatments for anxiety disorders using a transdiagnostic model. These studies generally support the efficacy of such treatments, although concern is apparent regarding the impact on therapeutic processes by including individuals with different DSM–IV anxiety disorder diagnoses within the same group. In particular, little is known about how a diagnostically heterogeneous format might impact group cohesion, treatment credibility, or therapeutic alliance. The current study examined treatment process variables from a sample of 54 individuals with an anxiety disorder diagnosis who participated in an open trial of a transdiagnostic anxiety treatment. Results replicated positive efficacy results presented elsewhere and suggested strong and increasing therapist therapeutic alliance and group cohesion throughout treatment. Furthermore, alliance and cohesion were generally related to better outcomes. Consequently, there appears to be little...
Lagging partial preferences for cryptic prey: a signal detection analysis of great tit foraging

Optimal foraging analyses generally prescribe a strategy for achieving an assumed objective, given the qualities, abundances, and distributions of prey (Pyke et al. 1977). Foragers, however, are not given "perfect knowledge" of these important variables; they must discriminate between potential prey of different quality and assess patterns of abundance on the basis of the limited information that is actually available to them (Orians 1981; Pulliam 1981; Werner and Mittelbach 1981). Most of the invertebrate prey taken by great tits are cryptic (Royama 1970), as are most prey animals in general (Mariath 1982). It should be particularly difficult for foragers to assess the quality, abundance, and distribution of cryptic and mimetic prey. We will develop the analogy between foraging for cryptic prey and basic signal detection problems, and then use the analogy to examine two of the consequences of imperfect knowledge: (1) Partial preferences result from limited discriminability between cryptic prey and nonprey. (2) Lagging changes in partial preference result from the need to estimate abundance by sequential sampling.
Using TD learning to simulate working memory performance in a model of the prefrontal cortex and basal ganglia

Delayed-response tasks (DRTs) have been used to assess working memory (WM) processes in human and nonhuman animals. Experiments have shown that the basal ganglia (BG) and dorsolateral prefrontal cortex (DLPFC) subserve DRT performance. Here, we report the results of simulation studies of a systems-level model of DRT performance. The model was trained using the temporal difference (TD) algorithm and uses an actor-critic architecture. The matrisomes of the BG represent the actor and the striosomes represent the critic. Unlike existing models, we hypothesize that the BG subserve the selection of both motor- and cognitive-related information in these tasks. We also assume that the learning of both processes is based on reward presentation. A novel feature of the model is the incorporation of delay-active neurons in the matrisomes, in addition to DLPFC. Another novel feature of the model is the subdivision of the matrisomal neurons into segregated winner-take-all (WTA) networks consisting of delay- versus transiently-active units. Our simulation model proposes a new neural mechanism to account for the occurrence of perseverative responses in WM tasks in striatal-, as well as in prefrontal damaged subjects. Simulation results also show that the model both accounts for the phenomenon of time shifting of dopamine phasic signals and the effects of partial reinforcement and reward magnitude on WM performance at both behavioral and neural levels. Our simulation results also found that the TD algorithm can subserve learning in delayed-reversal tasks.
The hydrophobic patch of ubiquitin is required to protect transactivator–promoter complexes from destabilization by the proteasomal ATPases

Mono-ubiquitylation of a transactivator is known to promote transcriptional activation of certain transactivator proteins. For the Sacchromyces cerevisiae transactivator, GAL4, attachment of mono-ubiquitin prevents destabilization of the DNA-transactivator complex by the ATPases of the 26S proteasome. This inhibition of destabilization depends on the arrangement of ubiquitin; a chain of ubiquitin tetramers linked through lysine 48 did not display the same protective effect as mono-ubiquitin. This led to an investigation into the properties of ubiquitin that may be responsible for this difference in activity between the different forms. We demonstrate the ubiquitin tetramers linked through lysine 63 do protect from proteasomal-mediated destabilization. In addition, we show that the mutating the isoleucine residue at position 44 interferes with proteasomal interaction in vitro and will abolish the protective activity in vivo. Together, these data implicate the hydrophobic patch of ubiquitin as required to protect transactivators from destabilization by the proteasomal ATPases.
BRANNSTROM, Christian (Ed.), Territories, Commodities and Knowledges: Latin American Environmental Histories in the Nineteenth and Twentieth Centuries, London, Institute for the Studies of the Americas, 2004, 323 pp

con las actuales circunstancias politicas de la region, a donde se ha trasladado otra la guerra de los ciclos extractivos de los recursos naturales. BRANNSTROM, Christian (Ed.), Territories, Commodities and Knowledges: Latin American Environmental Histories in the Nineteenth and Twentieth Centuries, London, Institute for the Studies of the Americas, 2004, 323 pp. Shawn Van Ausdal El libro editado por Christian Brannstrom es una contribucion muy bienvenida a la
Cytokine Regulation of Human Immunodeficiency Virus Type 1 Entry and Replication in Human Monocytes/Macrophages through Modulation of CCR5 Expression

Human macrophages express chemokine receptors that act as coreceptors for human immunodeficiency virus type 1 (HIV-1) and are major targets for HIV-1 infection in vivo. The effects of cytokines on HIV-1 infection of macrophages and on the expression of CCR5, the principal coreceptor for macrophage-tropic viruses, have now been investigated. Expression of CCR5 on the surface of freshly isolated human monocytes was virtually undetectable by flow cytometry with the monoclonal antibody 5C7. However, after culture of monocytes for 48 h in serum-free medium, approximately 30% of the resulting macrophages expressed CCR5 and the cells were susceptible to infection by macrophage-tropic HIV-1. Addition of either macrophage colony-stimulating factor (M-CSF) or granulocyte-macrophage colony-stimulating factor (GM-CSF) to the cultures markedly increased both the extent of HIV-1 entry and replication as well as surface expression of CCR5. In contrast, addition of the T-helper 2 (Th2) cell-derived cytokine interleukin-4 (IL-4) or IL-13 prevented the expression of CCR5 induced by culture in medium alone, and IL-4 inhibited virus entry, replication, and cytopathicity under these conditions. IL-4 or IL-13 also prevented the stimulatory effects of M-CSF or GM-CSF on CCR5 expression as well as HIV-1 entry and replication. In addition, IL-4 reversed the increase in CCR5 expression induced by pretreatment of cells with M-CSF. Although IL-10 also inhibits HIV-1 replication in macrophages, it did not suppress surface CCR5 expression induced by colony-stimulating factors. These results indicate that the cytokine environment determines the susceptibility of macrophages to HIV-1 infection by various mechanisms, one of which is the regulation of HIV-1 coreceptor expression.
Fabrication of Biologically Functionalized, Electrically Conducting, and Aligned Magnetic Nanoparticles

Fabrication of nanomaterials in precisely 1-D or 2-D fashion is very difficult because the particles are very much active when their dimension is reduced and they tend to aggregate. Self-aggregation of nanoparticles can be avoided by their templating growth. We have biofunctionalized the magnetic nanoparticles (iron), aligned them in a chain-like fashion, made them electrically conducting all by using DNA as template. We coated the particles by gold as gold coating prevents them from oxidization. Average size of the synthesized DNA templated Fecore -Aushell particles are found to be ~ 14 nm from transmission electron microscopy (TEM) analysis. Fourier transformed infrared (FTIR) spectroscopic analysis was performed to investigate the bonding between metal ions and the DNA chain. Magnetic measurements of the particles show that the particles are ferromagnetic within 80 ≤ T ≤ 300 K but saturation magnetization (MS) and coercivity (HC) decreases with increasing temperature. These DNA templated, trifunctional Fecore-Aushell particles have great potential of finding applications in magnetically driven, spin-dependent devices as well as in hybrid devices.
Microfluidic engineered high cell density three-dimensional neural cultures

Three-dimensional (3D) neural cultures with cells distributed throughout a thick, bioactive protein scaffold may better represent neurobiological phenomena than planar correlates lacking matrix support. Neural cells in vivo interact within a complex, multicellular environment with tightly coupled 3D cell–cell/cell–matrix interactions; however, thick 3D neural cultures at cell densities approaching that of brain rapidly decay, presumably due to diffusion limited interstitial mass transport. To address this issue, we have developed a novel perfusion platform that utilizes forced intercellular convection to enhance mass transport. First, we demonstrated that in thick (>500 µm) 3D neural cultures supported by passive diffusion, cell densities ≤5.0 × 103 cells mm−3 were required for survival. In 3D neuronal and neuronal–astrocytic co-cultures with increased cell density (≥104 cells mm−3), continuous medium perfusion at 2.0–11.0 µL min−1 improved viability compared to non-perfused cultures (p 90% viability in both neuronal cultures and neuronal–astrocytic co-cultures. This work demonstrates the utility of forced interstitial convection in improving the survival of high cell density 3D engineered neural constructs and may aid in the development of novel tissue-engineered systems reconstituting 3D cell–cell/cell–matrix interactions.
Jeremiah Curtin (1835-1906): His Life and Work as Linguist, Folklorist, and Translator

Jeremiah Curtin (1835-1906) was one of the outstanding linguistic field-workers of the 19th century, though much of his material remains in manuscript form. His scholarly reputation rests primarily on his activity as folklorist and translator of the works of Henryk Sienkiewicz (1846-1916), the Nobel Prize-winning novelist. Curtin was born in Detroit and brought up in the wilds of Wisconsin, where his parents, immigrants from Ireland, made a farm. Leaving home at 21, he worked his way through Harvard, learning new languages at every opportunity. After a brief period as a junior diplomat in St .Petersburg, he worked as a journalist and eventually joined the Bureau of American Ethnology as a field worker. His assignments took him to the Seneca, to various tribes in Oklahoma and to California and Oregon, where he gathered folktales, myths, and other linguistics materials from many languages of aboriginal America. Returning to Europe on numerous occasions, Curtin gathered and published folklore from Eastern Europe and Ireland; in addition, he continued his studies of the languages of the Caucasus, of India and Persia. Work in Siberia resulted in two volumes about the Mongols. Throughout much of the latter part of his life he continued his translations from the Russian and Polish.
Reconciling theory with observations: elements of a diagnostic approach to model evaluation

This paper discusses the need for a well-considered approach to reconciling environmental theory with observations that has clear and compelling diagnostic power. This need is well recognized by the scientific community in the context of the ‘Predictions in Ungaged Basins’ initiative and the National Science Foundation sponsored ‘Environmental Observatories’ initiative, among others. It is suggested that many current strategies for confronting environmental process models with observational data are inadequate in the face of the highly complex and high order models becoming central to modern environmental science, and steps are proposed towards the development of a robust and powerful ‘Theory of Evaluation’. This paper presents the concept of a diagnostic evaluation approach rooted in information theory and employing the notion of signature indices that measure theoretically relevant system process behaviours. The signature-based approach addresses the issue of degree of system complexity resolvable by a model. Further, it can be placed in the context of Bayesian inference to facilitate uncertainty analysis, and can be readily applied to the problem of process evaluation leading to improved predictions in ungaged basins. Copyright  2008 John Wiley & Sons, Ltd.
Six new species ofAcourtia (Asteraceae) and a historical account ofAcourtia mexicana

Six Mexican species ofAcourtia are described. One of these novelties seems to be related toAcourtia mexicana (Lag. ex D. Don) H. Rob., whose nomenclature has been misunderstood for decades; an exhaustive literature review and examination of herbarium material supports Robinson’s combination.
Using Ultrasound to Characterize Pulp Slurries With Entrained Air

The development of fast and practical methods for inspecting fiber suspensions is of great interest in the paper making industry. For process control and paper quality prediction, several elements of the refining process during paper making must be accurately monitored, including specific fiber properties, weight percent fiber (composition), degree of refining, amount of solids, and entrained air content. The results of previous ultrasonic studies applied to wood pulp provide guidance that ultrasound attenuation is information rich, and it does potentially provide a tool for consistency measurement. Ultrasound has the ability to penetrate dense suspensions such as wood pulp slurries. It is has been shown, in some studies, that ultrasound is sensitive to degree of refining. The effects of entrained air, additives, the origin and treatment of the fibers do however all influence the measured data. A series of measurements were made with hardwood and softwood slurries to evaluate the ability of measuring pulp consistency, solids, and entrained air. The attenuation through the slurry was measured as the ultrasound travels from one transducer through the slurry to the other. The measurements identified the presence of entrained air in the pulp samples. To better understand the effects of air, measurements were made at increasing pressures to show how increased pressure reduced the amount of air observed in the spectrum.Copyright © 2006 by ASME
Cytoplasmic Capes Are Nuclear Envelope Intrusions That Are Enriched in Endosomal Proteins and Depend upon βH-Spectrin and Annexin B9

It is increasingly recognized that non-erythroid spectrins have roles remote from the plasma membrane, notably in endomembrane trafficking. The large spectrin isoform, βH, partners with Annexin B9 to modulate endosomal processing of internalized proteins. This modulation is focused on the early endosome through multivesicular body steps of endocytic processing and loss of either protein appears to cause a traffic jam before removal of ubiquitin at the multivesicular body. We previously reported that βH/Annexin B9 influenced EGF receptor signaling. While investigating this effect we noticed that mSptiz, the membrane bound precursor of the secreted EGF receptor ligand sSpitz, is located in striking intrusions of the nuclear membrane. Here we characterize these structures and identify them as ‘cytoplasmic capes’, which were previously identified in old ultrastructural studies and probably coincide with recently recognized sites of non-nuclear-pore RNA export. We show that cytoplasmic capes contain multiple endosomal markers and that their existence is dependent upon βH and Annexin B9. Diminution of these structures does not lead to a change in mSpitz processing. These results extend the endosomal influence of βH and its partner Annexin B9 to this unusual compartment at the nuclear envelope.
MPI collective algorithm selection and quadtree encoding

We explore the applicability of the quadtree encoding method to the run-time MPI collective algorithm selection problem. Measured algorithm performance data was used to construct quadtrees with different properties. The quality and performance of generated decision functions and in-memory decision systems were evaluated. Experimental data shows that in some cases, a decision function based on a quadtree structure with a mean depth of three, incurs on average as little as a 5% performance penalty. In all cases, experimental data can be fully represented with a quadtree containing a maximum of six levels. Our results indicate that quadtrees may be a feasible choice for both processing of the performance data and automatic decision function generation.
THE KINETICS OF PENETRATION : V. THE KINETICS OF A MODEL AS RELATED TO THE STEADY STATE.

An organic potassium salt, KG, passes from an aqueous phase, A, through a non-aqueous layer, B, into a watery solution, C. In C it reacts with CO(2) to form KHCO(3). The ionic activity product (K) (G) in C is thus kept at such a low level that KG continues to diffuse into C after the concentration of potassium becomes greater in C than in A. Hence potassium accumulates in C, the osmotic pressure rises, and water goes in. A steady state is eventually reached in which potassium and water enter C in a constant ratio. The rate of entrance of potassium (with no water penetrating into C) may fall off in a manner approximately exponential. But water enters and may produce an exponential decrease in concentration. This suggests that the kinetics may be treated like that of two consecutive monomolecular reactions. Calculations made on this basis agree very well with the observed values. The rate of penetration appears to be proportional to the concentration gradient of KG in the non-aqueous layer and in consequence depends upon the partition coefficients which determine this gradient. Exchange of ions (passing as such through the non-aqueous layer) does not seem to play an important role in the entrance of potassium. The kinetics of the model may be similar to that of living cells.
Biculturalism and Cognitive Complexity Expertise in Cultural Representations

To explore the possible cognitive consequences of biculturalism, the authors examine the complexity of cultural representations in monocultural and bicultural individuals. Study 1 found that Chinese American biculturals' free descriptions of both American and Chinese cultures are higher in cognitive complexity than that of Anglo-American monoculturals, but the same effect was not apparent in descriptions of culturally neutral entities (landscapes). With the same procedures, Study 2 found that the cultural representations of biculturals with low levels of Bicultural Identity Integration (BII; or biculturals with conflicted cultural identities) are more cognitively complex than that of biculturals with high BII (biculturals with compatible cultural identities). This article shows that cultural frame switching and BII have meaningful cognitive consequences; furthermore, it suggests that exposure to more than one culture may increase individuals' ability to detect, process, and organize everyday cultural mean...
COMPLIANCE WITH THE OCCUPATIONAL SAFETY AND HEALTH ACT: A MATHEMATICAL PROGRAMMING FRAMEWORK

As a result of the passage of the Occupational Safety and Health Act of 1970, many employers are confronted with a multiple decision situation. The employer would like to comply with federally imposed standards as quickly as possible, but the employer must consider the budgetary limits under which he can profitably operate while achieving compliance. A goal programming model can be formulated to solve the problem. In this paper a review of the OSHA requirements is made, and a case example is presented to demonstrate the applicability of goal programming to resolving the budgetary pressure of OSHA compliance.
Using Cultural Skills for Cooperative Advantage in Japan

As US companies strive to compete in the global marketplace, managers who in the past never left the home office must now work with foreign colleagues. This paper provides a theoretical framework integrating culture, total quality, participant observation, and ethnography which has been integrated into a learning process for US-based managers and scientists who work with foreign colleagues. It discusses how Pharmco, a pharmaceutical subsidiary of a major US multinational, developed processes by which US-based managers and scientists learn to operate successfully in Japan and are using the learned processes in other cultures. It discusses the methods used by an anthropologically trained manager to demonstrate the need to learn anthropological tools and to use them to advantage in the business world. Empirical evidence indicates the success of the program.
Detecting Internet worms at early stage

Managing the security of enterprise networks has emerged to be a critical problem in the era of Internet economy. Arising as a leading threat, worms repetitively caused enormous damage to the Internet community during the past years. A new security service that monitors the ongoing worm activities on the Internet will greatly contribute to the security management of modern enterprise networks. This paper proposes an Internet-worm early warning system that automatically detects concerted scan activities and derives possible signatures of worm attacks. Its goal is to issue warning at the early stage of worm propagation and to provide necessary information for security analysts to control the damage. It reduces false positives by filtering out false scan sources. The system is locally deployable or can be codeployed amongst a group of enterprise networks. We provide both analytical and simulation studies on the responsiveness of this early warning system.
Design and Analysis of Algorithms for Shared-Memory Multiprocessors

Shared-memory multiprocessors feature parallelism and a steep cache hierarchy, two salient characteristics that distinguish them from the commodity processors of ten years ago. Both of these characteristics can be exploited effectively using the same general strategy: divide-and-conquer recursion. This talk overviews the Cilk multithreaded programming language being developed in the MIT Laboratory for Computer Science, which allows a programmer to exploit parallelism through divide-and-conquer. In addition, I show how divide-and-conquer allows caches to be used effectively.
Super-Resolution Imaging of DNA Replisome Dynamics in Live Bacillus Subtilis

DNA replication happens in all living organisms, and assures that the genome is accurately copied and maintained. The replisome is the molecular machine in cells that replicates DNA, and it is composed of several different proteins, including DNA polymerases, which directly synthesize DNA by adding nucleotides. Although the bacterial replisome has been studied extensively in vitro, little is known about the dynamics and architecture of replisome components in vivo. Here we use Bacillus subtilis, a Gram-positive bacterium commonly found in soil, as a model organism in which to study the architecture and dynamics of several replisome components in vivo. Photoactivated localization microscopy (PALM) and single-molecule tracking give a resolution of 20-40 nm, far below the diffraction limit of conventional microscopy, enabling us to localize and track every single protein molecule. In our study, we investigated the dynamics of a number of replisome components under different conditions, including the DNA polymerases PolC, and the β-clamp loader DnaX. We can watch the real time behavior of different replisome components during the DNA synthesis process, and study them quantitatively. Surprisingly, our investigations have revealed that all these replisome components are highly dynamic and exchange more rapidly than previously expected, and we characterize the molecular scale distribution of each replisome component within the dynamic replication machinery.
Seasonal Quantification of the Defensive Steroid Titer of Agabus seriatus (Coleoptera: Dytiscidae)

By means of a minnow bioassay, the prothoracic defensive steroid titer of a population of Agabus seriatus (Say) was quantified at monthly intervals over a 15-month period. The titer of defensive steroid varied seasonally. A minimum of ca. 25 µg deoxycorticosterone (DOC) per beetle was observed in October and November. Through the winter and spring the steroid titer increased progressively and a maximum of ca. 60 µg DOC per beetle was reached in the summer months. During September, the steroid titer sharply decreased to the fall minimum.
Targeting viral reservoirs: ability of antiretroviral therapy to stop viral replication.

PURPOSE OF REVIEW HIV infection is controlled but not cured by combination antiretroviral therapy. HIV may persist for a number of reasons, including ongoing cycles of HIV infection or viral persistence as latent, or HIV replication in long-lived cells containing HIV proviruses. Therapeutic consequences of these alternative mechanisms are significant and distinct. If ongoing replication remains during current antiretroviral therapy, then improvements in potency will be useful in eradication strategies. Alternatively, long-lived cells with integrated proviruses will not be affected by improvements in therapy directed against active infection, and new strategies will be necessary for HIV eradication. Technologic advances have made it possible to carry out a series of drug intensification protocols in well suppressed patients; these and other analyses for HIV replication have been useful to elucidate the nature of HIV persistence on therapy. RECENT FINDINGS A number of clinical studies intensifying antiretroviral therapy carried out in the last several years have yielded new findings regarding the ability to detect the presence of ongoing replication. Decreases in persistent viremia have not been consistently detected in individuals on potent combination antiretroviral therapy. Evidence for persistent replication has been reported in patients using sensitive assays of cell-associated HIV. SUMMARY HIV viremia persists despite combination antiretroviral therapy. Antiretroviral drug intensification does not lower the level of HIV measured in plasma, suggesting current therapy arrests active virus replication. HIV eradication will most likely require therapy in addition to potent antiretroviral therapy.