cssi/SciSciGPT-SciSciNet huggingface dataset:
Sun-Lamp for Emulsion Calibration

Although spectrographers can readily calibrate photographic emulsions for their own particular instrumentation, when reproduced elsewhere, the "exact" conditions often yield dissimilar results. The reason for this is in the quotation marks: it is not possible to reproduce conditions from one laboratory to another. There are uncontrollable variables in every source, in every photographic plate, in every spectrograph. This article proposes the use of a controlled excitation source to minimize one of these variables. In addition, data are given which show the potential usefulness of the source for comparing the spectral response (speed) of spectrographs, and for evaluating emulsions.
Migration of fresh human malignant astrocytoma cells into hydrated gel wafers in vitro.

Individual astrocytoma cells expressing a cytoplasmic form of pl85 c-neu migrated along basement membrane lined surfaces after xenografing fresh low or high grade human malignant astrocytomas into host rat brain. We now study the migratory capacity of fresh human malignant astrocytoma cells seeded on hydrated gel wafers composed of artificial basement membrane or collagen I, a normal and lesion-related CNS extracellular matrix component. Approximately 107 mechanically disrupted cells (with small clumps) of 3 fresh low grade and 6 fresh high grade astrocytomas were seeded on the surface of artificial basement membrane and collagen I wafers (11 × 16 mm). The wafers were then prepared for scanning electron microscopy and immunohistochemstry at 1, 3, 5, and 7 days after seeding. Regardless of tumor grade, a morphologically similar class of cells was observed to migrate through collagen I gels in 24 hours and 0.5–1.5 mm into artificial basement membrane gels in 7 days. Immunohistochemistry revealed that the migrated cells from low and high grade astrocytomas were positive for glial fibrillary acidic protein (GFAP)) and expressed cytoplasmic human-specific pl85 c-neu . These data indicate that fresh human malignant astrocytoma cells that contain GFAP and express cytoplasmic pl85 c-neu have a high degree of migratory capacity and could be the cell in the tumor involved in intraparenchymal metastasis and poor patient survival in high grade astrocytomas of the human brain.
An aircraft study of rapid precipitation development and electrification in a growing convective cloud

Abstract The rapid initial precipitation growth and initial electrification of a convective cloud, growing as a new cell on the upshear side of a cloud system in Florida, is traced from radar data and aircraft penetrations at the −7°C to −10°C level. This study combines radar, microphysical and electrical measurements so that an examination of the interactions between the cloud dynamics, microphysics and electrification is possible. The first pass (−7°C) was characterized by a strong 23 m/s updraft, all liquid cloud water, no precipitation, and no significant electrification. In the 300 s between the two penetrations, precipitation developed very rapidly from The electrification was observed to occur exclusively in the segments of the cloud pass where graupel were observed. Within this graupel region, where the graupel often coexisted with supercooled cloud liquid water, significant electric field occurred only at relative minima in the updraft. These relative velocity minima were also minima in the cloud liquid water content. The observed updraft velocities in these relative minima were close to balance velocities for the observed larger graupel hydrometeors. The strongest updrafts, where the formation and the riming growth of graupel was the greatest (maxima in cloud liquid water content), were not the locations of significant electrification at this flight level.
A 15-year experience with chemotherapy of patients with paraganglioma.

Background. Paraganglioma is a rare tumor thought to arise from the neuroectodermally derived paraganglionic cells that are dispersed widely along the autonomic ganglia. They can metastasize to bones, lymph nodes, and lungs and occasionally present with spinal cord compression. Up to 60% of retroperitoneal paragangliomas can be functional, with symptoms and signs of norepinephrine overproduction. Method. A 15-year experience with chemotherapy of patients with paraganglioma was reviewed. The patient population was identified through a search of the database maintained by the Departments of Melanoma-Sarcoma Medical Oncology and Pathology at the University of Texas M.D. Anderson Cancer Center (Houston, TX). Results. Thirteen of 84 patients with histologically confirmed diagnosis of paraganglioma were treated with chemotherapy. The median age was 42 years (range, 25–67 years); there were eight males and five females. Primary sites included retroperitoneum (seven patients), head and neck (two patients), pelvis, bladder, mediastinum, and paravertebral (one patient each). Twelve patients received chemotherapy for metastatic disease, and 1 had an unresectable mediastinal primary tumor. Eleven patients received cyclophosphamide, doxorubicin, and DTIC/dacarbazine (CyADIC)/cyclophosphamide, vincristine, doxorubicin and DTIC/dacarbazine (CyVADIC), and 2 received doxorubicin and dacarbazine (ADIC) at standard doses for a median of 4 cycles (range, 2–12 cycles). Six of 13 patients achieved an objective partial remission (response rate = 46%, 95% confidence interval = 19–73%); 6 other patients had stable disease, and one developed progressive disease. At the time of last follow-up, eight patients were alive with disease, four died, and one patient was alive with no evidence of disease. The median follow-up from diagnosis was 45 months (range, 12–300 months). Conclusion. Cyclophosphamide, doxorubicin, dacarbazine chemotherapy is active in the treatment of patients with paraganglioma.
Hydrodynamics of Copepods: A Review

This paper reviews the hydrodynamics of copepods, guided by results obtained from recent theoretical and numerical studies of this topic to highlight the key concepts. First, we briefly summarize observational studies of the water flows (e.g., the feeding currents) created by copepods at their body scale. It is noticed that the water flows at individual copepod scale not only determine the net currents going around and through a copepod’s hair-bearing appendages but also set up a laminar flow field around the copepod. This laminar flow field interacts constantly with environmental background flows. Theoretically, we explain the creation of the laminar flow field in terms of the fact that a free-swimming copepod is a self-propelled body. This explanation is able to relate the various flow fields created by copepods to their complex swimming behaviors, and relevant results obtained from numerical simulations are summarized. Finally, we review the role of hydrodynamics in facilitating chemoreception and mechanoreception in copepods. As a conclusion, both past and current research suggests that the fluid mechanical phenomena occurring at copepod body scale play an important role in copepod feeding, sensing, swarming, mating, and predator avoidance.
Nuclear Data Sheets Update for A = 200

Experimental data pertaining to nuclear structure of nuclei with mass number A=200 have been compiled and evaluated.
A new look at the stratigraphy, sedimentology and ammonite fauna of the Corallian Group (Oxfordian) of south Dorset

This paper presents the results of the first systematic study of the Corallian Group of south Dorset to be made since the 1930's. The Group is divided into six formations and descriptions of each formation are presented. The members of each formation are defined, and the stratigraphic nomenclature revised. The environment of accumulation of each member is discussed in relation to Corallian sedimentation in southern England. The Middle and Upper Oxfordian ammonite faunas are those of the Sub Boreal N.W. European Province. A full description of the zonal scheme is presented here, and several Upper Oxfordian ammonites figured.
Stitching videos streamed by mobile phones in real-time

User generated videos with mobile phone cameras are becoming more and more ubiquitous allowing people to share live content with remote parties, possibly in real-time. However with limited mobile phone capabilities, these videos are usually of small resolution, resulting in a small field of view for acceptable quality. Fortunately with the proliferation of video capture-enabled mobile phones, there is high chance that one or more persons will be shooting the same scene from different views. In this demonstration, we are showing an end-to-end system which receives video streams coming from different mobile phones, time synchronizes the streams and produces a single composite mosaic video, and all of this is done in real-time. The proposed system operates without coordination between users. The system has been tested under various capturing conditions such as indoor, outdoor, day and night conditions.
Factor VIII brand and immunogenicity

In this issue of Blood , Calvez et al and Collins et al, independently, add to the growing literature on the role of factor VIII brands and risk of hemophilia inhibitor formation.[1][1],[2][2] Ever since the observation that inhibitor titer waned after a fall in CD4+ count <200/μL in hemophilia
Family sociologists and policymaking: A supporting role perspective

Family sociologists do not set policymaking agendas. This is the role of elected officials and administrators with implementation power. Our functions as supporting players in the policymaking process are the following: 1) raising issues that foster or discourage policy development; 2) shaping arguments for proposed laws or administrative decrees; and 3) providing frameworks for development of legislative proposals. Examples of each function appear along with comments from persons involved in the policymaking process. There is also a discussion of the distinction between social scientists’ influence depending on their knowledge rather than their advocacy of specific proposals.
Effect of dietary crude protein content on skatole concentration in boar serum

Forty-eight Yorkshire × Chester White crossbred boars, 28 days of age, were assigned to one of four diets differing in crude protein content. Dietary crude protein content was 23% initially and then adjusted to 14, 17, 20 or 23% at 9 weeks of animal age, and 12, 15, 18 or 21% at 14 weeks of age, respectively. The skatole concentrations in serum of the boars was measured at 24, 32 and 40 weeks of age. Results showed that serum skatole concentrations declined (P < 0·05) with increasing age (0·034, 0·027 and 0·021 μg/ml at 24, 32 and 40 weeks, respectively) and also decreased (P < 0·059) with increasing dietary crude protein concentration (0·033, 0·026, 0·022 and 0·021 μg/ml at 12, 15, 18 and 21% in finishing diets, respectively).
Rho directs activation‐associated changes in rat hepatic stellate cell morphology via regulation of the actin cytoskeleton

Hepatic stellate cell activation, thought to play a key role in fibrosis of the liver, is characterized by changes in cellular morphology. The intracellular signals regulating morphological alterations associated with stellate cell activation are uncertain. The ras-like guanosine triphosphate-binding protein, rho, has recently emerged as an important regulator of the actin cytoskeleton, and consequently cell morphology. The aim of this study was to test the hypothesis that rho signaling pathways direct activation-associated morphological changes in stellate cells by regulating the actin cytoskeleton. The morphology and actin cytoskeleton of primary rat hepatic stellate cells were studied with phase contrast, differential interference contrast, and epifluorescence microscopy. Immunohistochemistry and immunoblot analysis were used to examine rho expression and activity, respectively. Quiescent and activated stellate cells were investigated in the absence and presence of C3 transferase, a bacterial toxin that specifically inhibits rho. Stellate cell activation was characterized by the development of prominent intracellular fibers, and the loss of dendrite-like processes and perinuclear retinoid droplets. Moreover, activation was accompanied by the formation of prominent actin stress fibers and focal adhesions. Both rho expression and activity were demonstrated in stellate cells. C3 transferase blocked and reversed, both activation-associated morphological alterations and activation-associated changes in the actin cytoskeleton, in quiescent and activated stellate cells, respectively. These results indicate that rho directs activation-associated changes in rat hepatic stellate cell morphology via regulation of the actin cytoskeleton.
Biotin sulfoxide reductase: Tryptophan 90 is required for efficient substrate utilization

Abstract Rhodobacter sphaeroides f. sp. denitrificans biotin sulfoxide reductase (BSOR) catalyzes the reduction of d-biotin d-sulfoxide to biotin and contains the molybdopterin guanine dinucleotide (MGD) cofactor as its sole prosthetic group. Comparison of the primary sequences of BSOR and the closely related enzyme dimethyl sulfoxide reductase (DMSOR) indicated a number of conserved residues, including an active-site tryptophan residue (W90), which has been suggested to be involved in hydrogen bonding to the oxo group on the Mo(VI) center in BSOR. Site-directed mutagenesis has been used to replace tryptophan 90 in BSOR with phenylalanine, tyrosine, and alanine residues to examine the role of this residue in catalysis. All three BSOR mutant proteins were purified to homogeneity and contained MGD. The mutant proteins retained very limited activity toward the oxidizing substrates tested, with W90F retaining the most activity (3.4% of wild type). All three W90 mutant proteins exhibited greatly reduced kcat values compared to that of the wild-type enzyme, which was accompanied by little change in K m app . In addition, the mutant proteins had perturbed visible absorption and circular dichroism spectra suggesting different oxidation states of the Mo center. Purified samples of wild-type BSOR did not exhibit electron paramagnetic resonance (EPR) signals indicating a Mo(VI) center. After redox-cycling, partially reduced samples of wild-type BSOR revealed a proton-split S=1/2 Mo(V) resonance (g1,2,3=1.999, 1.981, 1.967; A1,2,3=1.40, 1.00, 1.05 mT) analogous to that observed in DMSOR. In contrast, EPR studies of the purified W90 mutant proteins revealed distinct S=1/2 Mo(V) resonances that were resistant to both oxidation and reduction, indicating that the Mo was trapped in the intermediate Mo(V) oxidation state. These results strongly suggest that W90 in BSOR plays a critical role in catalysis by serving as a hydrogen bond donor to the oxo group on the Mo(VI) center.
Negative ion laser desorption ionization time-of-flight mass spectrometry of nitrated polycyclic aromatic hydrocarbons

Nitrated polycyclic aromatic hydrocarbons (nitro-PAHs) are widespread environmental pollutants that are generated by incomplete combustion and by atmospheric transformation of polycyclic aromatic hydrocarbons (PAHs). Many nitro-PAH compounds are potent genotoxins and some are direct acting mutagens. Detection of nitro-PAHs in aerosols is complicated by small sample sizes and nitro-PAH abundances that are 1–2 orders of magnitude less than analogous unsubstituted PAHs. Selective detection of several nitro-PAHs by using laser desorption ionization time-of-flight mass spectrometry in negative ion mode has been achieved. Desorption and ionization of nitro-PAHs were effected by using pulsed UV radiation at 266 and 213 ran. Intense molecular anions were observed in addition to fragments identified as CN− and NO2−, which were characteristic indicators of the presence of nitro-PAHs. Selective detection of nitro-PAHs in negative ion mode was demonstrated in the analysis of a diesel particulate sample.
Body Shape and Size and Insulin Resistance as Early Clinical Predictors of Hyperandrogenic Anovulation in Ethnic Minority Adolescent Girls

Abstract Purpose To determine whether key associated features of hyperandrogenic anovulation (HA) in predominately Caribbean Hispanic (CH) adolescent girls can be combined to improve the early diagnosis of HA. Methods Unselected observational sample of females aged 12 to 21 years (mean 17.5 ± 2.4 years), (64% CH, 28% African American). One hundred twenty subjects provided a menstrual history, had a physical examination, and a follicular phase fasting blood drawn for LH, FSH, testosterone, sex hormone binding globulin (SHBG), 17-OH progesterone (17-OHP), androstenedione (Δ 4 A), glucose, and insulin. We prospectively categorized subjects into four groups: G I (n = 42) had normal menses and normal physical exam; G II (n = 41) had normal menses and abnormal physical exam, that is, signs indicating possible hyperandrogenism and/or insulin resistance, including at least one of obesity, hirsutism, acne, or acanthosis nigricans; G III (n = 15) had abnormal menses and normal physical exam, and G IV (n = 22) had HA with BOTH abnormal menses and abnormal physical exam, that is, girls most likely to develop polycystic ovary syndrome. Hormonal levels and additional clinical and physical characteristics of interest were compared among the four groups. Results Group IV subjects had significantly higher waist circumference measurements, independent of overweight status, than all other groups. As hypothesized, Group IV subjects had significantly higher androgen levels and significantly lower SHBG levels than all other groups. FAI, SHBG, and waist circumference had the highest diagnostic accuracy for predicting Group IV status (i.e., HA phenotype). Conclusions Markers of insulin resistance and hyperandrogenemia, including waist circumference, FAI, and SHBG, best associate with irregular menstrual cycles and the HA phenotype in ethnic minority adolescent girls.
A viscoelastic-mass model for muscle

Abstract This work considers a viscoelastic-mass hypothesis which predicts length-tension, work-load, and force-velocity behavior for muscle-mass systems. The model is considered in detail with respect to its force-velocity and energy-load behavior. The model predicts that maximum shortening velocity (V max ) of a muscle-mass system depends, in a multiplicative manner, on the net initial force exerted by the muscle, the reciprocal of the total inertial mass, the reciprocal of the natural frequency of the system, and a factor (Zeta Factor) which depends entirely upon the damping ratio, ξ, of the system. The equation giving V max as a function of these four factors is similar in form to A.V. Hill's characteristic equation for muscle. The curvature of this theoretical force-velocity relation depends upon two parameters: Initial mass/Isometric mass (M0/M max ) and the value of ξ at zero added mass(after-load). Six sets of normalized force-velocity data from the literature are plotted and graphically compared with curves determined by the model.
Pharmacogenomic Modeling in Pancreatic Cancer—Response

We thank Avan and colleagues ([1][1]) for their interest in our pharmacogenomic (PGx) study of circulating tumor and invasive cells (CTIC) for predicting effective therapy in pancreatic ductal adenocarcinoma (PDAC; ref. [2][2]) and for their thoughtful comments. Regarding the first point, as is made
STRUCTURAL BIOLOGY RNA exerts self-control

A crystal structure of two bound RNA molecules not only provides insight into how regulatory riboswitch sequences affect messenger RNA expression, but also expands our understanding of RNA structure and architecture. See Letter p.363 Bacterial T-box riboswitches are found in the 5′ UTR of genes encoding aminoacyl-tRNA synthetases, the enzymes that charge tRNAs with amino acids. They differ from other riboswitches in that they bind tRNAs rather than a small molecule or metabolite to regulate expression. Jinwei Zhang and Adrian Ferre-D'Amare have now solved the crystal structure of the T-box tRNA binding region, Stem I, bound to tRNA. The long-awaited structure shows that this region binds not just the anticodon, but cradles the entire tRNA, forming an extended interface. Binding is facilitated by mutual induced fit in the T-box RNA and tRNA. The T-loop motifs mediate interactions that are similar to those of RNase P and a domain of the large ribosomal subunit, even though the three species do not have a common evolutionary ancestor.
Grain-size effect in viscoplastic polycrystals at moderate strains

Abstract This work deals with the prediction of grain-size dependent hardening in FCC and BCC polycrystalline metals at moderately high strains (2–30%). The model considers 3–D, polycrystalline aggregates of purely viscoplastic crystals, and simulates quasi-static deformation histories with a hybrid finite element method implemented for parallel computation. The hardening response of the individual crystals is considered to be isotropic, but modified to include a physically motivated measure of lattice incompatibility which is supposed to model, in the continuum setting, the resistance to plastic flow provided by lattice defects. The length-scale in constitutive response that is required on dimensional grounds appears naturally from physical considerations. The grain-size effect in FCC polycrystals and development of Stage IV hardening in a BCC material are examined. Though the grain-size does not enter explicitly into the constitutive model, an inverse relationship between the macroscopic flow stress and grain-size is predicted, in agreement with experimental results for deformation of FCC polycrystals having grain-sizes below 100 microns and at strains beyond the initial yield (>2%). The development of lattice incompatibility is further shown to predict a transition to Stage IV (linear) hardening upon saturation of Stage III (parabolic) hardening.
Crystallization behavior of α-phenyl o-cresol

The crystallization behavior of α-phenyl o-cresol (o-benzyl phenol) has been investigated over the range of undercooling up to 90 °C. The growth rate reaches a maximum value of about 10-3cm sec-1 at an undercooling of about 30 °C and decreases to about 10-7 cm sec-1 at the lowest temperature of study. The reduced growth rate versus undercooling relation has been constructed, and indicates an interface site factor which increases continuously with increasing undercooling. The logarithm of growth rate × viscosity does not decrease linearly with increasing 1TδT. The variation of the growth rate with temperature, as well as the corresponding variation of the interface morphology, cannot be described in satisfactory detail by any standard theoretical model. The forms of these variations are in agreement with the predictions of Jackson for materials characterized by large entropies of fusion.
Remote sensing and GIS technologies for monitoring and prediction of disasters

Remote sensing and GIS technologies for monitoring and prediction of disasters, edited by Shailesh Nayak and Sisi Zlatanova, Oxford, NY, Springer, 2010, vii introduction +270 pp., US$159.00 (hardba...
Surveillance: Radiographic imaging with cosmic-ray muons.

Natural background particles could be exploited to detect concealed nuclear materials. Despite its enormous success, X-ray radiography1 has its limitations: an inability to penetrate dense objects, the need for multiple projections to resolve three-dimensional structure, and health risks from radiation. Here we show that natural background muons, which are generated by cosmic rays and are highly penetrating, can be used for radiographic imaging of medium-to-large, dense objects, without these limitations and with a reasonably short exposure time. This inexpensive and harmless technique may offer a useful alternative for detecting dense materials — for example, a block of uranium concealed inside a truck full of sheep.
The c2 domains of human synaptotagmin 1 have distinct mechanical properties.

Synaptotagmin 1 (Syt1) is the Ca+2 receptor for fast, synchronous vesicle fusion in neurons. Because membrane fusion is an inherently mechanical, force-driven event, Syt1 must be able to adapt to the energetics of the fusion apparatus. Syt1 contains two C2 domains (C2A and C2B) that are homologous in sequence and three-dimensional in structure; yet, a number of observations have suggested that they have distinct biochemical and biological properties. In this study, we analyzed the mechanical stability of the C2A and C2B domains of human Syt1 using single-molecule atomic force microscopy. We found that stretching the C2AB domains of Syt1 resulted in two distinct unfolding force peaks. The larger force peak of ∼100 pN was identified as C2B and the second peak of ∼50 pN as C2A. Furthermore, a significant fraction of C2A domains unfolded through a low force intermediate that was not observed in C2B. We conclude that these domains have different mechanical properties. We hypothesize that a relatively small stretching force may be sufficient to deform the effector-binding regions of the C2A domain and modulate the affinity for soluble N-ethylmaleimide-sensitive factor (NSF) attachment protein receptors (SNAREs), phospholipids, and Ca+2.
The Federal Art Project in Illinois: 1935-1943

Started "because people were hungry," by the time the project ended, it had given artists the opportunity to study art, to meet other artists, to develop disciplined work habits, to manage their production with some business sense, and most importantly, to work without interruption.The authors include 32 photographs of Illinois Art Project artwork, locations, and personnel.
Modeling cellular deformations using the level set formalism

Many cellular processes involve substantial shape changes. Traditional simulations of these cell shape changes require that grids and boundaries be moved as the cell's shape evolves. Here we demonstrate that accurate cell shape changes can be recreated using level set methods (LSM), in which the cellular shape is defined implicitly, thereby eschewing the need for updating boundaries. We obtain a viscoelastic model of Dictyostelium cells using micropipette aspiration and show how this viscoelastic model can be incorporated into LSM simulations to recreate the observed protrusion of cells into the micropipette faithfully. We also demonstrate the use of our techniques by simulating the cell shape changes elicited by the chemotactic response to an external chemoattractant gradient. Our results provide a simple but effective means of incorporating cellular deformations into mathematical simulations of cell signaling. Such methods will be useful for simulating important cellular events such as chemotaxis and cytokinesis.
Preserving a legacy for our patients: The bedside-to-bench award in translational research

The Journal of Translational Medicine is pleased to announce a prize to recognize outstanding contributions in the field of translational medicine. This year, the Bedside-to-Bench Award was provided by an anonymous donor and supported by the Journal of Translational Medicine Editorial Board. Applications should be submitted directly to the Journal of Translational Medicine [1].
An evaluation of red blood cell heterogeneity (increased red blood cell distribution width) in iron deficiency of pregnancy

Summary A new classification of anemias, which is based on mean corpuscular volume and quantitative anisocytosis (red blood cell distribution width), was evaluated in 331 pregnant women on initial presentation for prenatal care. Seventy-four of them had severe iron depletion (serum ferritin level ⪯ 10 ng/dl). Contrary to the above classification, early iron deficiency without anemia was infrequently identified by an increase in distribution width (4 of 25 patients). The distribution width was not consistently increased in the 49 anemic, iron-deficient patients; 34 were normal and would have been considered to have thalassemia minor or anemia of chronic disease according to the new classification. The distribution width was no more sensitive than the mean corpuscular volume in suggesting iron deficiency. This study does not confirm the usefulness of the new classification in the diagnosis of iron deficiency in this patient population. (Am J Obstet Gynecol 1989;160:336-9.)
The transnational protection regime and democratic breakthrough in Taiwan and South Korea

External state pressure is understood to have played a causally significant role in democratic breakthrough in Taiwan and South Korea during the 1980s. This article problematizes the international dimensions of democratization in Taiwan and South Korea by first providing a revisionist account of external agency which involved complex networks of transnational nonstate and substate actors. These included human rights activists, Christian churches and related ecumenical organizations, members of the Taiwanese and Korean diaspora communities in the US, academics and students, foreign journalists, and members of the US Congress. In forming a transnational “protection regime” during the 1970s and 1980s to protect the political opposition from repressive governments, they contributed to the development of effective democratic movements. The case studies provide us with a more comprehensive view of the international dimensions of democratization, speaking to both the country specific and general theoretical lite...
Evaluating the role of retinal membrane guanylyl cyclase 1 (RetGC1) domains in binding guanylyl cyclase-activating proteins (GCAPs).

Retinal membrane guanylyl cyclase 1 (RetGC1) regulated by guanylyl cyclase-activating proteins (GCAPs) controls photoreceptor recovery and when mutated causes blinding disorders. We evaluated the principal models of how GCAP1 and GCAP2 bind RetGC1: through a shared docking interface versus independent binding sites formed by distant portions of the cyclase intracellular domain. At near-saturating concentrations, GCAP1 and GCAP2 activated RetGC1 from HEK293 cells and RetGC2−/−GCAPs1,2−/− mouse retinas in a non-additive fashion. The M26R GCAP1, which binds but does not activate RetGC1, suppressed activation of recombinant and native RetGC1 by competing with both GCAP1 and GCAP2. Untagged GCAP1 displaced both GCAP1-GFP and GCAP2-GFP from the complex with RetGC1 in HEK293 cells. The intracellular segment of a natriuretic peptide receptor A guanylyl cyclase failed to bind GCAPs, but replacing its kinase homology and dimerization domains with those from RetGC1 restored GCAP1 and GCAP2 binding by the hybrid cyclase and its GCAP-dependent regulation. Deletion of the Tyr1016–Ser1103 fragment in RetGC1 did not block GCAP2 binding to the cyclase. In contrast, substitutions in the kinase homology domain, W708R and I734T, linked to Leber congenital amaurosis prevented binding of both GCAP1-GFP and GCAP2-GFP. Our results demonstrate that GCAPs cannot regulate RetGC1 using independent primary binding sites. Instead, GCAP1 and GCAP2 bind with the cyclase molecule in a mutually exclusive manner using a common or overlapping binding site(s) in the Arg488–Arg851 portion of RetGC1, and mutations in that region causing Leber congenital amaurosis blindness disrupt activation of the cyclase by both GCAP1 and GCAP2.
Toxoplasma gondii cyst wall formation in activated bone marrow-derived macrophages and bradyzoite conditions.

Toxoplasma gondii is an obligate intracellular parasite that can invade any nucleated cell of warm-blooded animals. During infection, T. gondii disseminates as a fast replicating form called the tachyzoite. Tachyzoites convert into a slow-growing encysted form called the bradyzoite by a signaling process that is not well characterized. Within animals, bradyzoite cysts are found in the central nervous system and muscle tissue and represent the chronic stage of infection. Conversion to bradyzoites can be simulated in tissue culture by CO2 starvation, using medium with high a pH, or the addition of interferon gamma (IFNγ). Bradyzoites are characterized by the presence of a cyst wall, to which the lectin Dolichos biflorus agglutinin (DBA) binds. Fluorescently labeled DBA is used to visualize the cyst wall in parasites grown in human foreskin fibroblasts (HFFs) that have been exposed to low CO2 and high pH medium. Similarly, parasites residing in murine bone marrow-derived macrophages (BMMs) display a cyst wall detectable by DBA after the BMMs are activated with IFNγ and lipopolysaccharide (LPS). This protocol will demonstrate how to induce conversion of T. gondii to bradyzoites using a high pH growth medium with low CO2 and activation of BMMs. Host cells will be cultured on coverslips, infected with tachyzoites and either activated with addition of IFNγ and LPS (BMMs) or exposed to a high pH growth medium (HFFs) for three days. Upon completion of infections, host cells will be fixed, permeabilized, and blocked. Cyst walls will be visualized using rhodamine DBA with fluorescence microscopy.
Wetlands : history, current status, and future

Wetlands have been intricately linked with humankind throughout the ages. Evidence of rice culture dates to the earliest age of humans, long before the era of historical records. Drain-field and raised-field agriculture occurred in wetlands throughout large areas of Mesoamerica before Hispanic exploration of the region. About 40% of the world's population uses rice as a major staple; rice culture currently occupies about 15% of the world's wetland area. Wetlands are valued for high biological productivity; as filters, sinks, and transformers for sediments, nutrients, and pollutants; and as buffers between aquatic systems and human activities on upland areas. Because of their varied ecological functions, wetlands are of interest to ecotoxicologists as potential sites for detoxifying pollutants. Estimates are that wetlands occupy about 3 to 6% of the world's land area. Attempts to define, delineate, monitor, and regulate the use of wetlands in the United States have proven to be extremely complex. Considerable progress has been made in classifying and monitoring changes in wetland areas on a nationwide basis, but less success has been achieved in defining and delineating wetlands. The United States experience should be a useful model for developing countries to study as they attempt to deal with wetland management and protection. As long as the world's population continues to grow at exponential rates, it seems highly probable that pressure to use wetlands to meet society's demands will increase. Consequently, opportunities to set aside reserves will decrease, and the role that wetlands play in maintaining quality of life will depend more and more on our collective ability to develop and promote compatible uses on wetlands.
Independent characterization of thymidine transport and subsequent metabolism in Hymenolepis diminuta—I. Comparison of short- and long-term transport kinetics

Abstract 1. 1. Initial transport kinetics of thymidine in the rat tapeworm, Hymenolepis diminuta have been characterized independently of subsequent metabolic activity, using short term (5s) incubation times. 2. 2. Thymidine uptake by 10 day old worms using long-term (2 min) incubation times underrepresents actual transport capabilities by allowing subsequent phosphorylation to act as a rate limiting step in the coupled transport-metabolism pathway. 3. 3. Apparent K t values for 6 and 10 day old H. diminuta thymidine transport at 5 s incubation times (0.073 nM and 0.091 mM) are close in value. Distinctions previously observed at 2 min incubation times may actually represent metabolic (and not transport) differences.
Improved delivery through biological membranes XX: Nicotinamide----dihydronicotinamide based ester-linked redox carrier systems.

The 1-carboxyalkyl nicotinamide ⇌ dihydronicotinamide redox pair is a new type of brain-enhanced chemical delivery system for drugs containing hydroxyl groups. The rate of oxidation of the dihydro carrier form and subsequent “lock-in” into the brain of the quaternary carrier-drug species, as well as the rate of the hydrolytic release of the drug, depend on both the length and branching of the alkyl chain separating the carrier ring system. Testosterone was used as a model drug, and it was successfully released in a sustained and enhanced manner to the brain in significantly higher concentrations than with the previously reported trigonelline ⇌ dihydrotrigonelline carrier system.
Drosophila kinesin: characterization of microtubule motility and ATPase.

Abstract Preparations of kinesin, a microtubule-based force-producing protein, have been isolated from Drosophila melanogaster embryos by incubation of microtubules with a nonhydrolyzable ATP analogue and gel filtration of proteins released from the microtubules by ATP. These preparations induced MgATP-dependent microtubule gliding in vitro with a Km for MgATP of 44 microM and a Vmax for gliding of 0.9 micron/sec. Samples of Drosophila proteins that were active in motility assays possessed an average ATPase activity in solution of 17 nmol/min per mg that increased to an average of 106 nmol/min per mg in the presence of microtubules. The major polypeptides that copurified with these activities showed relative molecular masses of 115 kDa and 58 kDa. An antiserum raised against the 115-kDa polypeptide also recognized the 110-kDa component of squid kinesin preparations and the 130-kDa component of sea urchin kinesin preparations.
An invariant-manifold analysis of electrophoretic traveling waves

A new, geometric proof of a theorem of Fife, Palusinski, and Su on electrophoretic traveling waves is presented. The proof is based upon the perturbation theory for invariant manifolds due to Fenichel. The results proved here reproduce the existence, uniqueness, and asymptotic approximation theorem proved by Fifeet al. The proof given here is substantially simpler, and in addition, it provides additional insight into the geometric structure of the phase space of the traveling wave equations for this system.
Nature versus nurture: predictability in low-temperature Ising dynamics.

Consider a dynamical many-body system with a random initial state subsequently evolving through stochastic dynamics. What is the relative importance of the initial state (``nature'') versus the realization of the stochastic dynamics (``nurture'') in predicting the final state? We examined this question for the two-dimensional Ising ferromagnet following an initial deep quench from $T=\ensuremath{\infty}$ to $T=0$. We performed Monte Carlo studies on the overlap between ``identical twins'' raised in independent dynamical environments, up to size $L=500$. Our results suggest an overlap decaying with time as ${t}^{\ensuremath{-}{\ensuremath{\theta}}_{h}}$ with ${\ensuremath{\theta}}_{h}=0.22\ifmmode\pm\else\textpm\fi{}0.02$; the same exponent holds for a quench to low but nonzero temperature. This ``heritability exponent'' may equal the persistence exponent for the two-dimensional Ising ferromagnet, but the two differ more generally.
Student Financial Aid and the College Enrollment Decision: The Effects of Public and Private Grants and Interest Subsidies.

Abstract A multi-period household utility maximization model is the basis for the estimation of a binomial logit model to investigate the effects of four types of student financial aid on the college enrollment decision of high school seniors from the class of 1980. Publicly provided grants are seen to have a significant and positive effect on the decision and tend to increase college enrollments of individuals from lower income households. Other types of student financial aid, including privately funded scholarships and the interest subsidy from public and private source student loans, are found to have no measurable effect on the enrollment decision.
Resilient and performance-guaranteed composite services in cloud computing

Services offered by different cloud service providers can be federated into composite services that can execute a variety of tasks subject to a service level agreement (SLA). An SLA is defined as quality of service (QoS) metrics and a fee. In this paper, we consider the QoS metrics: trustworthiness, percentile response time, and vulnerability. The percentile response time metric is a statistical bound stating that the end-to-end response time is less than a given bound for a certain percent of time. We first describe an efficient and accurate numerical solution for the calculation of the percentile response time. Then, we consider all these QoS metrics in a resilient and performance-guaranteed cloud service composition problem that typically arises in inter cloud computing. We present a framework for tackling the SLA-guaranteed cloud service composition problem in which an optimisation problem subject to QoS constraints is solved using an efficient numerical approach.
Evaluation of the impact of resolution-sensitivity tradeoffs on detection performance for SPECT imaging

We evaluated the impact of resolution versus sensitivity tradeoffs on the detection performances of SPECT imaging systems. Images were reconstructed using penalized likelihood with quadratic penalties and the theoretical approximation for the SNR of the Hotelling observer was used as the detection metric. We compared three circularly rotating pinhole SPECT systems with identical detector areas and fields of view (FOVs): The first system consisted of a single pinhole and the projection of the FOV occupied the entire detector area at each view angle. The second system had four pinholes and no overlap between the projections due to increased minification. The third system had nine pinholes with significant overlap between the projections. The systems emphasized resolution, sensitivity and very-high number of counts via overlap, respectively. We simulated 2:1 and 4:1 contrast tumors with 5, 15 and 25 mm diameters within a 100×100×100mm3 FOV. The four and nine pinhole systems had improved detection performance over the single pinhole system for all simulated contrast and tumor sizes and had almost identical detection performances for the 5 mm tumor. For the larger tumors, the nine pinhole system was slightly better (approx. 10%). These results indicate that the sensitivity advantage gained by using four pinholes instead of one outweighs the loss in resolution and results in improved detection performance. On the other hand, the advantage gained by adding further pinholes with overlapping projections was minimal.
Conformational changes of pyrene-labeled polyelectrolytes with pH: effect of hydrophobic modifications.

Structural changes of pyrene-labeled and unlabeled poly(maleic acid/octyl vinyl ether) (PMAOVE) and poly(maleic acid/methyl vinyl ether) (PMAMVE) with changes in pH have been investigated in this study. The changes in the photophysical properties of pyrene are interpreted to investigate uncoiling or swelling of the polymeric chains with pH. The vibrational fine structure of the pyrene fluorescence (I3/I1) and the ratio between excimer and monomer fluorescence (Ie/Im) of both pyrene-labeled and unlabeled PMAMVE and PMAOVE suggest that, at pH 4, the polymers are in the coiled form and PMAOVE forms hydrophobic nanodomains. An increase in pH ionizes a number of COOH groups on both PMAMVE and PMAOVE, which leads to the stretching or swelling of the polymers.
Exciting Young Students in Grades K-8 about STEM through an Afterschool Robotics Challenge.

In this paper, we describe the successful implementation of an afterschool LEGO robotics program for elementary and middle school students that is annually offered by the Whitacre College of Engineering at Texas Tech University. Three events are held on campus: the kickoff, a trial run, and the competition, spread over a period of eight weeks. In between the events, participants design their LEGO robots at the school, mostly during afterschool clubs. Through our program, we broaden the participation in hands-on robotics tasks which apply STEM concepts to groups that otherwise might not have the opportunity. Success factors of our implementation are the flexibility of the implementation at the local level, the inclusion of engineering students as mentors and volunteers, and the low cost for organizers and participants. We provide evidence that we have reached a diverse student population in grades K-8 and positively changed their attitudes toward STEM, then we report the benefits that teachers see in regular participation in the event. Finally, we describe the benefit of involving engineering undergraduate students as mentors and volunteers.
Instructional Materials for Diverse Learners Features and Considerations for Textbook Design1

In today's diverse classrooms, teachers need and students deserve educational tools that serve a wide range of learners. Fortunately, making instructional materials more accommodating does not have to mean sacrificing the needs of one group of students for those of another. Many features that are good for diverse learners are good for all learners. Text characteristics that have been shown to enhance learning are proposed to improve the audience appropriateness, text organization, and use of organizational aids in instructional materials. Reform of the design, selection, and use of materials will require a concerted effort by publishers, policymakers, and practitioners.
Effect of particle size distribution on strength of precipitation-hardened alloys

Aging of precipitation hardened alloys results in particle coarsening, which in turn affects the strength. In this study, the effect of particle size distribution on the strength of precipitation-hardened alloys was considered. To better represent real alloys, the particle radii were distributed using the Wagner and Lifshitz and Slyozov (WLS) particle size distribution theory. The dislocation motion was simulated for a range of mean radii and the critical resolved shear stress (CRSS) was calculated in each case. Results were also obtained by simulating the dislocation motion through the same system but with the glide plane populated by equal strength particles, which represent mean radii for each of the aging times. The CRSS value with the WLS particle distribution tends to decrease for lower radii than it does for the mean radius approach. The general trend of the simulation results compares well with the analytical values obtained using the equation for particle shearing and the Orowan equation.
Urban Planning, Community Participation, and the Roxbury Master Plan in Boston

This article examines the role and impact of community participation in the development of the Roxbury Master Plan in Boston, Massachusetts. It describes how residents and activists utilized the Roxbury Master Plan as a tool to raise challenges to planning ideas perceived as detrimental to the neighborhood. Discussion of this master plan provides a laboratory for examining race and class relationships and tensions generated by proposals for economic development strategies based on benefiting powerful institutional players as a way of helping low-income neighborhoods. Review of the development of this neighborhood master plan between the period 1999 and 2003 shows how residents can use community participation to ensure adoption of broad economic development strategies advocated by proponents of big business that do not spell dislocation and gentrification for poor and working-class neighborhoods. The case study also represents a critique of smart growth and New Urbanism as planning concepts in terms of how...
The Green500 List: Year one

The latest release of the Green500 List in November 2008 marked its one-year anniversary. As such, this paper aims to provide an analysis and retrospective examination of the Green500 List in order to understand how the list has evolved and what trends have emerged. In addition, we present community feedback on the Green500 List, particularly from two Green500 birds-of-a-feather (BoF) sessions at the International Supercomputing Conference in June 2008 and SC|08 in November 2008, respectively.