cssi/SciSciGPT-SciSciNet huggingface dataset:
Exercise-induced ventricular arrhythmias and cardiovascular death.

Background: Exercise-induced ventricular arrhythmias (EIVA) are frequently observed during exercise testing. However, the clinical guidelines do not specify their significance and so we examined this issue in our population. Methods: A retrospective analysis of prospectively collected data was performed on 5754 consecutive male veterans referred for exercise testing at two university-affiliated Veterans Affairs Medical Centers. Exercise test responses were recorded and cardiovascular mortality was assessed after a mean follow-up of 6 ± 4 years. EIVA were defined as frequent premature ventricular complexes (PVCs) constituting more than 10% of all ventricular depolarizations during any 30-second ECG recording, or a run of three or more consecutive PVCs during the exercise test or recovery. Results: EIVA occurred in 426 patients (7.4%). There were 550 (10.6%) cardiovascular deaths during follow-up. Seventy two (17%) patients with EIVA died of cardiovascular causes, whereas 478 (9.0%) of patients without EIVA died of cardiovascular causes (P < 0.001). Patients with EIVA had a higher prevalence of cardiovascular disease, resting PVCs, resting ST depression, and ischemia during exercise than patients without EIVA. In a Cox hazards model adjusted for age, cardiovascular disease, exercise-induced ischemia, ECG abnormalities, exercise capacity and risk factors, EIVA was significantly associated with time to cardiovascular death. The combination of both resting PVCs and EIVA was associated with the highest hazard ratio. Conclusions: EIVA are independent predictors of cardiovascular mortality after adjusting for other clinical and exercise test variables; combination with resting PVCs carries the highest risk.
Suppression of peritoneal dissemination through protecting mesothelial cells from retraction by cancer cells.

In a previous study, we demonstrated that calponin h1 suppressed tumor growth of transformed cells and that the peritonitis carcinomatosa induced by mouse B16-F10 melanoma (F10) cells was more extensive in calponin h1-deficient (CN−/−) mice with fragility of mesothelial (MS) cells than in their calponin h1-wild (CN+/+) counterparts. In our study, we assessed the therapeutic effect of calponin h1 on peritoneal dissemination. F10 cells were overlaid on the cultured CN+/+ or CN−/− MS cells and the effect of calponin h1 on retraction of MS cells was evaluated. Then, an adenoviral vector with the calponin h1 gene (AdGFP-CN) inserted was constructed and was applied to CN−/− MS cells or CN−/− mouse peritoneum to investigate its suppressive effect on the peritoneal dissemination caused by F10 cells. Greater retraction and invasion of F10 cells were observed in CN−/− MS than in CN+/+ cells in vitro, while down-regulation of calponin h1 was observed in CN+/+ MS cells prior to the invasion of F10 cells. Infecting CN−/− MS cells with AdGFP-CN prevented their retraction and the invasion of F10 cells. Peritoneal dissemination was prominently suppressed in AdGFP-CN-infected CN−/− mice, and the survival of those mice was significantly prolonged. Thus, calponin h1 functioned to protect host MS cells from the invasion of F10 cells. © 2003 Wiley-Liss, Inc.
Field-sensitive addressing and control of field-insensitive neutral-atom qubits

The establishment of a scalable scheme for quantum computing with addressable and long-lived qubits would provide a route to harnessing the laws of quantum physics to solve classically intractable problems. The design of many proposed platforms for quantum computing is driven by competing needs: isolating the quantum system from the environment to prevent decoherence, and easily and accurately controlling the system with external fields. For example, neutral-atom optical-lattice architectures provide environmental isolation through the use of states that are robust against fluctuating external fields, yet external fields are essential for qubit addressing. Here, we demonstrate the selection of individual qubits with external fields, while the qubits are in field-insensitive superpositions. We use a spatially inhomogeneous external field to map selected qubits to a different field-insensitive superposition, minimally perturbing unselected qubits, despite the fact that the addressing field is not spatially localized. We show robust single-qubit rotations on neutral-atom qubits located at selected lattice sites. This precise coherent control should be more generally applicable to state transfer and qubit isolation in other architectures using field-insensitive qubits. A quantum computer requires quantum systems that are well-isolated from external perturbations, but which can still be easily manipulated with external fields. A scheme that uses spatially inhomogeneous fields to selectively address neutral-atom qubits while they are in field-insensitive superposition states satisfies these competing needs.
Efficient Visualization of Large-Scale Data Tables through Reordering and Entropy Minimization

Visualization of data tables with n examples and m columns using heat maps provides a holistic view of the original data. As there are n! ways to order rows and m! ways to order columns, and data tables are typically ordered without regard to visual inspection, heat maps of the original data tables often appear as noisy images. However, if rows and columns of a data table are ordered such that similar rows and similar columns are grouped together, a heat map may provide a deep insight into the underlying data distribution. We propose an information-theoretic approach to produce a well-ordered data table. In particular, we search for ordering that minimizes entropy of residuals of predictive coding applied on the ordered data table. This formalization leads to a novel ordering procedure, EM-ordering, that can be applied separately on rows and columns. For ordering of rows, EM-ordering repeats until convergence the steps of (1) rescaling columns and (2) solving a Traveling Salesman Problem (TSP) where rows are treated as cities. To allow fast ordering of large data tables, we propose an efficient TSP heuristic with modest O(n log(n)) time complexity. When compared to the existing state-of-the-art reordering approaches, we show that the method often provides heat maps of higher visual quality, while being significantly more scalable. Moreover, analysis of real-world traffic and financial data sets using the proposed method, which allowed us to readily gain deeper insights about the data, further confirmed that EM-ordering can be a valuable tool for visual exploration of large-scale data sets.
Solar neutron observations and their relation to solar flare acceleration problems

We review the current observational knowledge on the production of neutrons in association with solar flares. From a study of the observations it is shown that unique information can be obtained on the spectral properties of accelerated ions produced during the flare. Also, the abundance of 3He/H in the photosphere can be directly determined. We also review the current interpretations of all available neutron observations and in particular highlight the uncertainties, and provide guide posts for future experiments.
Better Together: Responsive Community Programming at the U-M Library

ABSTRACTIn the past seven years, the University of Michigan Library's programming model has evolved to be responsive and reflective of staffing areas of interest and expertise. Our team-based, iterative model enables us to develop responsive exhibits, workshops, experiences, and events in our community. This article explores our experiences in developing this model through the lens of some of our collaborations with the Ann Arbor District Library (AADL). Our approach to programming opportunities builds on learning by doing, building deeper, mutually beneficial relationships with other organizations, and continually making sure we are truly developing programming with our audience (our community) in mind. While public and academic libraries often develop distinct sets of services, collections, and expertise to serve their respective communities, successful collaborations can yield interesting opportunities for more effective engagement and programming. Our relationship with AADL has helped us to identify a...
The frequency and pattern of normal tremor.

Abstract Average patterns of normal finger tremor, BCG and EKG, and interval histograms of finger tremor were obtained from seven healthy young adults with the aid of a Computer of Average Transients (400-B). This finger tremor can be averaged and a well-defined pattern established. Cardiac action as the origin of normal finger tremor is confirmed. Two distinct peaks can be identified in the average tremor pattern. The first and second occur respectively with the first and second footward movements in the BCG. It is suggested that handward displacement of the body is responsible for these peaks in finger tremor. The major rhythm as shown in the study of interval histograms is actually 11–13 c/sec, a frequency somewhat faster and in a narrower range than the findings of other investigators. A possible reason for such discrepancy is discussed. The irregular fast rhythm of 17–30 c/sec fails to show up in either average tremor pattern or in the interval histogram. This rhythm is therefore not depend on heartbeat and its regularity and constancy of occurrence are not statistically significant.
Newer concepts of cancer of the colon and rectum: cellular immunity to human colonic carcinomas.

Human colonic carcinomas have common antigen(s), also identified in carcinomas of the pancreas and stomach, and lymphocytes from cured as well as from tumor-bearing patients with these tumors can destroy cultivated neoplastic cells of these types. Lymphocytes from patients with colonic carcinomas are cytotoxic to cultivated epithelial cells of the fetal gut as well. Sera from patients with progressively growing colonic carcinomas, but not from cured patients, can block destruction of colonic carcinoma cells by the immune lymphocytes.
Surgical manipulation of the uterine environment of rat fetuses.

Abstract A surgical technique to manipulate the amniotic fluid of individual rat fetuses is described. The normal appearance and suckling behavior of operated animals suggest that the procedure is benign.
Confinement of triality

Abstract It is shown that matrix elements computed between the physical states in gauge theories have one of the following features. particles carrying center charges are either confined or propagating but their charge is screened completely by some unusual states of the gauge field. Thus the center charge is permanently confined. The deconfined screened matrix elements support particles with unusual spin-statistics.
Monoclonal Antibody Against Vascular Cell Adhesion Molecule-1 Inhibits Neointimal Formation After Periadventitial Carotid Artery Injury in Genetically Hypercholesterolemic Mice

Abstract—Vascular cell adhesion molecule (VCAM)-1 is induced in smooth muscle cells after arterial injury, in which it has been implicated in the recruitment of inflammatory cells to the site of injury. To investigate the effect of hypercholesterolemia on VCAM-1 induction after injury and the role of VCAM-1 in neointimal response to injury, we injured the carotid artery of wild-type and apolipoprotein E null (KO) mice fed normal and high cholesterol chow. We demonstrate a graded response of VCAM-1 induction as well as monocyte/macrophage infiltration by immunohistochemistry 3 days after injury that correlated with increasing circulating cholesterol levels. Three weeks after injury, KO mice fed high cholesterol chow (KO HC group) had a significantly greater neointimal formation compared with wild-type and KO mice fed normal chow (P<0.05). Inhibition of VCAM-1 function in the KO HC group by monoclonal antibody treatment significantly reduced monocyte/macrophage infiltration and neointimal formation. There w...
Acute myocardial infarction associated with prolonged sneezing

Abstract Acute myocardial infarction (AMI) has been reported with normal coronary anatomy, and many causes and inciting events have been implicated. We report AMI associated with sneezing in a young man with normal coronary arteries.
Some indications for combining individual and family therapy

Abstract This paper discusses combining individual and family therapy and focuses specifically upon the serial sequence of individual-family individual sessions with young adults who have problems with individuation, social withdrawal, and identity. Case examples are presented to illustrate the need for a combination of individual and family therapy. The goals and techniques of both individual and family sessions are discussed as well as the advantages of combining the therapies.
Upregulated Expression of Integrin α1 in Mesangial Cells and Integrin α3 and Vimentin in Podocytes of Col4a3-Null (Alport) Mice

Alport disease in humans, which usually results in proteinuria and kidney failure, is caused by mutations to the COL4A3, COL4A4, or COL4A5 genes, and absence of collagen α3α4α5(IV) networks found in mature kidney glomerular basement membrane (GBM). The Alport mouse harbors a deletion of the Col4a3 gene, which also results in the lack of GBM collagen α3α4α5(IV). This animal model shares many features with human Alport patients, including the retention of collagen α1α2α1(IV) in GBMs, effacement of podocyte foot processes, gradual loss of glomerular barrier properties, and progression to renal failure. To learn more about the pathogenesis of Alport disease, we undertook a discovery proteomics approach to identify proteins that were differentially expressed in glomeruli purified from Alport and wild-type mouse kidneys. Pairs of cy3- and cy5-labeled extracts from 5-week old Alport and wild-type glomeruli, respectively, underwent 2-dimensional difference gel electrophoresis. Differentially expressed proteins were digested with trypsin and prepared for mass spectrometry, peptide ion mapping/fingerprinting, and protein identification through database searching. The intermediate filament protein, vimentin, was upregulated ∼2.5 fold in Alport glomeruli compared to wild-type. Upregulation was confirmed by quantitative real time RT-PCR of isolated Alport glomeruli (5.4 fold over wild-type), and quantitative confocal immunofluorescence microscopy localized over-expressed vimentin specifically to Alport podocytes. We next hypothesized that increases in vimentin abundance might affect the basement membrane protein receptors, integrins, and screened Alport and wild-type glomeruli for expression of integrins likely to be the main receptors for GBM type IV collagen and laminin. Quantitative immunofluorescence showed an increase in integrin α1 expression in Alport mesangial cells and an increase in integrin α3 in Alport podocytes. We conclude that overexpression of mesangial integrin α1 and podocyte vimentin and integrin α3 may be important features of glomerular Alport disease, possibly affecting cell-signaling, cell shape and cellular adhesion to the GBM.
An Analysis of the Performance of a Gas Turbine Cogeneration Plant

A computer program has been developed to analyze the thermodynamic performance of a cogeneration plant. Results of parametric studies using this program include partial load operation, inlet air cooling, and supercharging. Fuel chargeable to power, a previously used figure-of-merit, is used to evaluate the performance for partial-load operation. Fuel chargeable to incremental power and differential steam efficiency are two new figures-of-merit for evaluating other design alternatives: the former for incremental increases in electric power output, the latter for incremental increases in steam output at the expense of electrical power output.
Headspace diffusion limitations on heterogeneous catalysis in unstirred batch reactors

Abstract Headspace gas diffusion can affect measurements of catalytic rate constants in unstirred batch reactors when the reaction occurs in a small pile of catalyst within the reactor. To quantify these effects, the governing equations for catalysis in a round-bottom flask were solved numerically in a toroidal coordinate system. We also introduce a simpler model reactor geometry that preserves the essential characteristics of a typical bench-scale flask-reactor. The preserved characteristics include the reactor volume, an averaged diffusion length scale, and the area of the catalyst pile. An eigenfunction expansion solution for the model reactor closely parallels the full numerical solutions in the round-bottom flask reactor, thus confirming the validity of the simplified model reactor. Solutions for the model reactor show that concentrations measured above the catalyst pile decay exponentially to equilibrium even when transport limitations are important. Therefore, exponential decay rates in these reactors should not be equated to first order (or pseudo-first order) reaction rate constants without first checking carefully for diffusion limitations. Two dimensionless parameters govern the reactor performance. Effectiveness factors are computed for unstirred catalytic batch reactors over a wide range of the two dimensionless parameters. Our findings show quantitatively when headspace stirring is and is not necessary. When stirring is inconvenient or impossible, the tabulated effectiveness factors can be used to design reactors that are small enough, with kinetics that are slow enough, and with the catalyst dispersed over a large enough area to avoid headspace diffusion limitations.
Cytochrome P-450 cholesterol 7α-hydroxylase: Inhibition of enzyme deactivation by structurally diverse calmodulin antagonists and phosphatase inhibitors

Cytochrome P-450 cholesterol 7 alpha-hydroxylase (P-450Ch7 alpha) catalyzes the first and rate-limiting step in the conversion of cholesterol to bile acids. Incubation of rat liver microsomes in 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid buffer resulted in a time-dependent deactivation of P-450Ch7 alpha which was markedly accelerated by the nonionic detergent Tween 80. Microsomal NADPH-cytochrome P-450 reductase and cytochrome P-450-dependent 7-ethoxycoumarin O-deethylase activities were unaffected under these conditions, evidencing the selectivity of the deactivation process for P-450Ch7 alpha. The rate (t 1/2 = 15-19 min at 37 degrees C) and maximal extent of P-450Ch7 alpha deactivation (greater than or equal to 90%) were both unaffected by the presence of cytosolic proteins and were also not dependent on the initial enzyme level, as shown using liver microsomes isolated from untreated, cholestyramine-fed, and xenobiotic-induced rats exhibiting an eight-fold range in P-450Ch7 alpha activity. Scavengers for reduced oxygen species were also without effect. P-450Ch7 alpha was stabilized some six- to sevenfold (t 1/2 = 94-143 min) by the phosphatase inhibitor NaF. Of a series of other phosphatase inhibitors examined, including, among others, EDTA, vanadate, and molybdate, only phosphate-containing compounds and the calmodulin antagonist trifluoperazine, and inhibitor of the Ca2+-calmodulin-dependent phosphatase calcineurin, effectively stabilized P-450Ch7 alpha. Modulation of P-450Ch7 alpha deactivation by these inhibitors generally paralleled their effects on isolated calcineurin. A variety of structurally diverse calmodulin antagonists examined were also found to effectively protect P-450Ch7 alpha from deactivation; these include calmidazolium and tamoxifen (IC50 = 25 to 50 microM), chlorpromazine, thioridazine, amitriptyline, imipramine, and the naphthalene sulfonamide compound W-7 (IC50 = 50 to 300 microM). Structure-activity analysis of several phenothiazines and their derivatives indicated that although little activity was exhibited by the sulfoxides, some protection was provided by the corresponding sulfones. On the basis of these observations, various models for the molecular basis of enzyme deactivation are considered, including the hypothesis that a calcineurin-like microsomal phosphatase mediates deactivation of this cytochrome P-450 enzyme.
Quark clusters and the deep-inelastic structure functions of nuclei

We show that any simple two-component cluster model can represent the European Muon Collaboration data reasonably well; thus the model is not sensitive to the data.
Functions of sibling aggression in the spotted hyaena, Crocuta crocuta

Sibling rivalry, occurring in the form of intense aggression directed at siblings, has been described in many birds, but few mammals. In the spotted hyaena, early aggression directed at littermates has been hypothesized to function as a mechanism for litter reduction by siblicide, particularly within same-sex litters. Alternatively, intralitter aggression might serve to establish and maintain a rank relationship between twin littermates. Our goal here was to use long-term observations of 46 litters to test these two hypotheses in wild Crocuta. Rates of sibling aggression were high during the first 2 months of life, but then dropped to low levels. During the first year of life, littermates fought mainly over milk and meat, both of which are critical food resources, and dominant cubs were heavier than subordinate siblings of the same age. Rates at which mixed-sex littermates fought did not differ significantly from fighting rates within same-sex litters. Rates of intralitter aggression were higher when local prey were scarce than when prey were abundant. Although we found no significant effect of maternal social rank on cub aggression rates, our results were consistent with the notion that aggression rates within litters vary with maternal rank. Our results did not support the hypothesis that intralitter aggression functions to mediate siblicide, particularly within same-sex litters. Instead, our results were consistent with the hypothesis that early sibling aggression in Crocuta functions to establish and maintain a rank relationship within the litter.
Dissection of the Stepwise Mechanism to β-Lactam Formation and Elucidation of a Rate-determining Conformational Change in β-Lactam Synthetase

Abstract Clavulanic acid is a widely used β-lactamase inhibitor whose key β-lactam core is formed by β-lactam synthetase. β-Lactam synthetase exhibits a Bi-Ter mechanism consisting of two chemical steps, acyl-adenylation followed by β-lactam formation. 32PPi-ATP exchange assays showed the first irreversible step of catalysis is acyl-adenylation. From a small, normal solvent isotope effect (1.38 ± 0.04), it was concluded that β-lactam synthesis contributes at least partially to kcat. Site-specific mutation of Lys-443 identified this residue as the ionizable group at pKa ∼ 8.1 apparent in the pH-kcat profile that stabilizes the β-lactam-forming step. Viscosity studies demonstrated that a protein conformational change was also partially rate-limiting on kcat attenuating the observed solvent isotope effect on β-lactam formation. Adherence to Kramers' theory gave a slope of 1.66 ± 0.08 from a plot of log(okcat/kcat) versus log(η/ηo) consistent with opening of a structured loop visible in x-ray data preceding product release. Internal “friction” within the enzyme contributes to a slope of >1 in this analysis. Correspondingly, earlier in the catalytic cycle ordering of a mobile active site loop upon substrate binding was manifested by an inverse solvent isotope effect (0.67 ± 0.15) on kcat/Km. The increased second-order rate constant in heavy water was expected from ordering of this loop over the active site imposing torsional strain. Finally, an Eyring plot displayed a large enthalpic change accompanying loop movement (ΔH‡ ∼ 20 kcal/mol) comparable to the chemical barrier of β-lactam formation.
The distribution of orthogonal arrays and their relationship to intercellular junctions in neuroglia of the freeze-fractured hypothalamo-neurohypophysial system

Using freeze-fracture techniques, we have investigated membrane specializations of the glia associated with the hypothalamo-neurohypophysial system of the rat. In the paraventricular (PVN) and supraoptic (SON) nuclei, astrocytes in areas of high neuronal density (i.e., magnocellular regions) display orthogonal arrays of 6–7 nm particles soley near gap junctions, while astrocytes in areas of lower neuronal density (i.e., parvocellular regions) contain additional arrays in membranes not displaying gap junctions. Arrays are especially numerous on astrocytic perivascular end-feet in both nuclei and in the laminations of the pial-glial limitans ventral to the SON. Ependymal cells near the PVN show arrays both on their lateral surfaces (displaying gap junctions) and on their apical surfaces (facing the CSF). Tight junctions are not noted on astrocytes or ependymal cells, but are noted on both the somas and myelin lamellae of oligodendroglia. Both of these latter membranes occasionally contain gap junctions as well; however, orthogonal arrays are never noted on oligodendroglia. The plasma membranes of pituicytes in the neurohypophysis display gap junctions, complex junctions, and tight junctions. Orthogonal arrays are noted near the first two of these, but not near the last. Arrays in the neural lobe appear most dense on membranes adjacent to subpial or perivascular spaces. Pituicyte membranes containing orthogonal arrays appear infrequently near the neural stalk, increasing towards the distal end of the neural lobe. The distribution of orthogonal arrays in this system, as well as in other systems in which they have been noted, suggests a polarization of membrane activity.
Low-frequency fluctuations in external cavity semiconductor lasers: understanding based on a simple dynamical model

We investigate the dynamical origin of low-frequency fluctuations (LFFs) in external cavity semiconductor lasers by utilizing a simplified, three-dimensional model derived from the infinite-dimensional Lang-Kobayashi (LK) equations. The simplified model preserves the dynamical properties of the external-cavity modes (ECMs) and antimodes which play a fundamental role in the generation of LFFs. This model yields a clear picture of the dynamical origin of the LFFs. Two distinct regions are observed in parameter space, one with the presence of the maximum-gain mode (MGM), and another without it. In particular, we show that, in the absence of noise, LFFs are a consequence of the dynamical interactions among different ECMs and antimodes. When a small amount of noise is present, LFFs result from an intermittent switching of trajectories among different coexisting attractors in the phase space. The presence of double peaks in the distribution of power dropout times, which has been observed recently in experiments, is explained, and a scaling relation is obtained between the average switching time and the noise strength.
In vivo competition studies of Z-(-,-)-[125I]IQNP against 3-quinuclidinyl 2-(5-bromothienyl)-2-thienylglycolate (BrQNT) demonstrating in vivo m2 muscarinic subtype selectivity for BrQNT.

Alzheimer’s disease (AD) involves selective loss of muscarinic m2, but not m1, subtype neuroreceptors in cortical and hippocampal regions of the human brain. Until recently, emission tomographic study of the loss of m2 receptors in AD has been limited by the absence of available m2-selective radioligands that can penetrate the blood-brain barrier. We now demonstrate the in vivo m2 selectivity of an analog of (R)-QNB, 3-quinuclidinyl 2-(5-bromothienyl)-2-thienylglycolate (BrQNT), by dissection and autoradiographic studies of the in vivo inhibition of radioiodinated Z-1-azabicyclo[2.2.2]oct-3-yl α-hydroxy-α-(1-iodo-1-propen-3-yl)-α-phenylacetate (Z-(-,-)-[125I]IQNP) binding by unlabeled BrQNT in rat brain. In the absence of BrQNT, Z-(-,-)-[125I]IQNP labels brain regions containing muscarinic receptors, with an enhanced selectivity for the m2 subtype. In the presence of 60–180 nmol of co-injected racemic BrQNT, Z-(-,-)-[125I]IQNP labeling in those brain regions containing predominantly m2 subtype is reduced to background levels, while levels of radioactivity in areas not enriched in the m2 subtype do not significantly decrease. We conclude that BrQNT is m2-selective in vivo, and that [76Br]BrQNT, or a radiofluorinated analog, may be of potential use in positron emission tomographic (PET) study of the loss of m2 receptors in AD. In addition, a radioiodinated analog may be of potential use in single photon emission tomographic (SPECT) studies.
Development of a Mouse ESC Reporter Line to Isolate Purkinje-Like Cardiac Conduction System Cells

Background We previously demonstrated that the cell adhesion protein contactin2 (Cntn2) is enriched in Purkinje cells of the cardiac conduction system (CCS). The objective of this study was generation of a mouse embryonic stem cell (mESC) reporter line that allows identification of Purkinje-like cardiomyocytes in vitro. Methods and Results mESC were generated from transgenic mice carrying a BAC Cntn2-eGFP reporter gene and were subsequently transduced with lentivirus coding for a MHCα-mCherry cardiomyocyte reporter gene. Immunostaining analysis confirmed that mESC expressed markers of pluripotency (Oct3/4; Klf4) and spontaneously differentiated into cells of all three germ layers in the absence of LIF (α-smooth muscle actin, β-tubulin, α-fetoprotein). Spontaneous or serum-free directed cardiac differentiation resulted in generation of spontaneously beating cardiomyocytes, of which single positive MHCα-mCherry cells comprised 57.76% ± 3.7% and MHCα-mCherry/Cntn2-eGFP cells comprised 1.9% ± 0.9% of the total population as determined by fluorescence-activated cell sorting (FACS) (n = 5 differentiation cultures). Quantitative real-time PCR analysis of FACS isolated double-positive cells verified cardiomyocyte-specific transcript expression (Mlc2v: 33-fold, P P P P 50 = 79.9 ± 10.4 ms, APD 90 = 170.2 ± 17.5 ms, n=11) compared with eGFP-negative cardiomyocytes (APD 50 = 53.4 ± 9.4 ms, APD 90 = 120.6 ± 17.3 ms, n=15), consistent with their assignment as Purkinje-like derivatives. Conclusions We established an mESC reporter line that allows for the identification and enrichment of ventricular CCS derivatives. This model should be useful for downstream studies of CCS development and pathology, including the role of Purkinje cells as arrhythmogenic triggers. Cntn2 may also be a useful marker of CCS-like cells derived from human embryonic stem and/or induced pluripotent stem cells.
Unusual ice diamicts emplaced during the December 15, 1989 eruption of Redoubt volcano, Alaska

Abstract Ice diamict comprising clasts of glacier ice and subordinate rock debris in a matrix of ice (snow) grains, coarse ash, and frozen pore water was deposited during the eruption of Redoubt Volcano on December 15, 1989. Rounded clasts of glacier ice and snowpack are as large as 2.5 m, clasts of Redoubt andesite and basement crystalline rocks reach 1 m, and tabular clasts of entrained snowpack are as long as 10 m. Ice diamict was deposited on both the north and south volcano flanks. On Redoubt's north flank along the east side of Drift piedmont glacier and outwash valley, ice diamict accumulated as at least 3 units, each 1–5 m thick. Two ice-diamict layers underlie a pumice-lithic fall tephra that accumulated on December 15 from 10:15 to 11:45 AST. A third ice diamict overlies the pumiceous tephra. Some of the ice diamicts have a basal ‘ice-sandstone’ layer. The north side icy flows reached as far as 14 km laterally over an altitude drop of 2.3 km and covered an area of about 5.7 km2. On Crescent Glacier on the south volcano flank, a composite ice diamict is locally as thick as 20 m. It travelled 4.3 km over an altitude drop of 1.7 km, covering about 1 km2. The much higher mobility of the northside flows was influenced by their much higher water contents than the southside flow(s). Erupting hot juvenile andesite triggered and turbulently mixed with snow avalanches at snow-covered glacier heads. These flows rapidly entrained more snow, firn, and ice blocks from the crevassed glacier. On the north flank, a trailing watery phase of each ice-diamict flow swept over and terraced the new icy deposits. The last (and perhaps each) flood reworked valley-floor snowpack and swept 35 km downvalley to the sea. Ice diamict did not form during eruptions after December 15 despite intervening snowfalls. These later pyroclastic flows swept mainly over glacier ice rather than snowpack and generated laharic floods rather than snowflows. Similar flows of mixed ice grains and pyroclastic debris resulted from the November 13, 1985 eruption of Nevado del Ruiz volcano and from eruptions of snowclad Mount St. Helens in 1982–1984. Such deposits at snowclad volcanoes are initially broad and geomorphically distinct, but they soon become extensively reworked and hard to recognize in the geologic record.
Large-Area Patterning of Coinage-Metal Thin Films Using Decal Transfer Lithography

We describe two new procedures that appear to hold significant promise as means for patterning thin-film microstructures of the coinage metals (Cu, Ag, Au). A feature central to both is the modification of their surfaces to promote the adhesive transfer of PDMS thin-film microstructures, a material suitable for use as resist layers in large-area patterning, using Decal Transfer Lithography (DTL). The present work provides a significant extension of the capabilities of DTL patterning, providing general protocols that can be used to transfer decal resists to essentially any substrate surface. The first method involves the functionalization of a surface, specifically those of gold and silver films with a thiol-terminated silane coupling agent, (mercaptopropyl)trimethoxysilane. This self-assembled monolayer, when hydrolyzed to its silanol form, provides a robust adhesion-promoting layer suitable for use in DTL patterning. The second method exploits the surface chemistry provided by the deposition of a nanosca...
An Alternative Approach to Measure the Interferometer Transfer Function

Current methods to quantify transfer function of an interferometric test are limited to off-line characterization of interferometer itself. We propose an in situ technique for measuring instrument transfer function of a complete interferometric test system.
Analysis of mass transfer kinetics in the biosorption of synthetic dyes onto Spirulina platensis nanoparticles

Abstract In this research, the mass transfer kinetics for the biosorption of synthetic dyes (acid blue 9 and FD&C red no. 40) by Spirulina platensis nanoparticles was analyzed under different experimental conditions. The external mass transfer model (EMTM) and the homogeneous solid diffusion model (HSDM) were employed to study the mass transfer kinetics and also to estimate the values of external mass transfer coefficient ( k f ) and intraparticle diffusion coefficient ( D int ). The Biot number (Bi) was used to verify the importance of external mass transfer in relation to intraparticle diffusion. The values of external mass transfer coefficient ( k f ) ranged from 1.67 × 10 −6 to 11.40 × 10 −6 cm s −1 and the intraparticle diffusion coefficient ( D int ) ranged from 0.70 × 10 −14 to 4.30 × 10 −14 cm 2 s −1 . The Biot numbers (0.53 ≤ Bi ≤ 10.33) showed that, for both dyes, the biosorption onto S. platensis nanoparticles was controlled simultaneously by external mass transfer and intraparticle diffusion.
An Association‐Wide Ethics Discussion

: Lisa Frink is contributing editor of “Ethical Currents”, the AAA Committee on Ethics column in Anthropology News.
Knocking off their Sox: lineage-specific repression by Polycomb in epidermal stem cells.

A recent publication in The EMBO Journal (Bardot et al , 2013) provides novel insights into lineage specification during the development of the mouse skin. Ezhkova and colleagues demonstrate that Ezh1 and Ezh2, core enzymes of the Polycomb Repressive Complex (PRC), restrict differentiation of Merkel cells, a specialized population of mechanosensory cells by directly repressing the cell fate determinant transcription factor (TF) Sox2 in epidermal progenitors. Generally, lineage determination starts with morphogenetic gradients, triggering signalling events that converge on specific TFs, which in turn remodel one cellular state into another. With the exception of a few cases, such as Oct4 and Nanog in embryonic stem cells (ESCs) and MyoD in muscle cells, lineage determinant TFs are not cell type specific. Instead, unique combinations confer certain differentiation states (Boyer et al , 2006). Given the right combination of TFs, many cells to work with, and sufficient time, it might actually be possible to convert any cell type into another. Examples range from transdifferention of fibroblasts into muscle cells or neurons (Pournasr et al , 2011) to turning terminally differentiated cells into pluripotent stem cells (Yamanaka and Blau, 2010). However, such dramatic fate …
A series connected solar air heating system using the FMTC collector and the rolling cylinder heat store

Abstract An annual performance simulation has been carried out using the FMTC collector, the rolling cylinder heat store with Glauber's Salt, and a dwelling, all arranged in a series connected solar air heating system. The results suggest that a modest size system can readily carry the entire heating load of an energy efficient home in any geographical region of the U.S. The energy required to drive the system, i.e. rolling cylinder drive energy plus air blower drive energy, is always an important fraction of the total system output. In Boston 1958 weather the seasonal COP varies from 2.5 to 5.8 depending on the particular rolling cylinder design configuration selected. 90 per cent of the system drive energy is base load for the electric utility. There are no “coldest day peaks” resulting from electric backup heating. A system using the highest drive energy configuration may be sized for 99.5 per cent solar system heating using the same design chart at any northern region of the U.S.A. One system sized for Boston was evaluated at seven other geographical locations. The resulting house size was always in the acceptable range. This raises the possibility that one or a few standardized system sizes could serve an area as large as the U.S. Individualized solar system design calculations would not be necessary. Cloudy weather performance was noticeably improved in Boston (1958 weather). On a seasonal basis the FMTC collector delivered three times more heat than a typical flat plate (TFP) collector and 60 per cent of that heat was collected at insolation levels which were below the functional cut-off level of the TFP collector.
Characterization of a blue mutant of Rhodospirillum rubrum.

Abstract A carotenoidless, blue mutant of Rhodospirillum rubrum strain S1 was isolated and characterized with respect to its nutritional requirements, growth kinetics and absorption spectra. The mutant contained bacteriochlorophyll a and the carotenoid phytoene, required reduced sulfur compounds for growth under photosynthetic conditions, and produced H2S when sulfur was supplied as cystine. The specific growth rate, bacteriochlorophyll a, and protein content of the mutant were comparable to its wild type parent under most conditions; however, when the mutant was transferred from photosynthetic to chemo-organotrophic conditions in the light, the mutant rapidly lost viability.
Present and future directions of basic research on polymeric materials

Polymer science is in the midst of profound changes in direction. Historically, the foundation of polymer science has been primarily chemistry, i.e., the preparation of polymers and physical-chemical studies of their properties. At the present time, the frontiers of the science are being pushed increasingly toward condensed-matter physics and materials science. One reason for this trend is, undoubtedly, the intellectual nourishment that polymer scientists are finding in these fertile fields which, themselves, are undergoing some great changes of their own. Another, of perhaps even greater potential importance, is the discovery by many scientists with little prior interest in polymers that these materials offer an intellectually challenging area of research. A still further impetus comes from the demands of dynamic “high-technology” industries for new materials with new properties. Eventually, bridges will also be built to the biological sciences. All of these changes are occurring at a time when the ever-increasing power of the instrumentation and computers available to the researcher is providing new insights. Together, these forces are reshaping the way in which basic research on polymeric materials will be conducted in the future.
How Fast Is Excitation Energy Transfer in the Photosystem II Reaction Center in the Low Temperature Limit? Hole Burning vs Photon Echo

The Qy(S1) excitonic structure, excitation energy transfer (EET), and primary charge-transfer separation processes of the isolated photosystem II reaction center (PS II RC) have proven to be formidable problems due, in part, to the severe spectral congestion of the So→Qy absorption spectrum. Recently, Prokhorenko and Holzwarth (J. Phys. Chem. B 2000, 104, 11563) reported interesting femtosecond 2-pulse photon echo data on the RC at 1.3 K for excitation wavelengths between 676 and 686 nm. At times longer than ∼1 ps and λ ≳ 678 nm, the echo decay curves are highly dispersive, which was attributed to a distribution of primary charge separation rates ranging from 2 ps to several hundred ps. A prompt subpicosecond component of the echo decay curves was also observed and suggested to be due to EET occurring in ∼100−200 fs. We present here persistent nonphotochemical hole burned spectra and transient triplet bottleneck hole spectra obtained with burn wavelengths between 680 and 686 nm, which show that the EET ti...
Robust regulation with H 2 performance

Abstract We consider the problem of minimizing the H 2 norm of a feedback system subject to the constraint that the controller robustly regulate against constants and sinusoids. We show that, for any ϵ > 0, there exists a controller that both achieves robust regulation and renders the closed-loop H 2 norm within ϵ of the optimal norm (the norm achievable without the robust regulation constraint). We also provide conditions that are both necessary and sufficient for there to exist a robustly regulating controller that achieves the optimal H 2 norm. All proofs are constructive.
Access to Mars from Earth–Moon libration point orbits: Manifold and direct options

Abstract This investigation is focused specifically on transfers from Earth–Moon L 1 / L 2 libration point orbits to Mars. Initially, the analysis is based on the circular restricted three-body problem to utilize the framework of the invariant manifolds. Various departure scenarios are compared, including arcs that leverage manifolds associated with the Sun–Earth L 2 orbits as well as non-manifold trajectories. For the manifold options, ballistic transfers from Earth–Moon L 2 libration point orbits to Sun–Earth L 1 / L 2 halo orbits are first computed. This autonomous procedure applies to both departure and arrival between the Earth–Moon and Sun–Earth systems. Departure times in the lunar cycle, amplitudes and types of libration point orbits, manifold selection, and the orientation/location of the surface of section all contribute to produce a variety of options. As the destination planet, the ephemeris position for Mars is employed throughout the analysis. The complete transfer is transitioned to the ephemeris model after the initial design phase. Results for multiple departure/arrival scenarios are compared.
Occurrence of jaundice during treatment with perphenazine and beta-phenylisopropylhydrazine

Two cases of jaundice that developed during the course of treatment with two new psychodynamic agents—beta-phenylisopropylhydrazine (Catron), and perphenazine (Trilifon)—have been described.
Regenerative reconstruction of a tract in a rat's brain.

Abstract The problem of unequivocally demonstrating regeneration of severed axons toward their former destination in such a way as to rebuild a tract is complicated by the resulting anatomical perfection of such a postulated repair, and the need to prove that the axons were cut in the first place. Therefore, a dorsoventral incision was made through the brain of an adult rat with the curved portion of a U-shaped loop of wire. It remained in the living brain for 18 days and completed its progress through the brain by being pulled out through the ventral surface after fixation. The brain was stained by a pyridine silver method and sections were counterstained with Luxol Fast Blue and Nuclear Fast Red. The incision, defined between the two lumens where the arms had been located, was crossed by some appropriately directed axons of the medial lemniscus, thus demonstrating directionally selective regeneration in the mammalian brain. The predominant fiber pattern suggested regeneration around the cut.
Assessment of smoking status based on cotinine levels in nasal lavage fluid

Cotinine is a principal metabolite of nicotine with a substantially longer half-life, and cotinine levels in saliva, urine or serum are widely used to validate self-reported smoking status. The nasal cavity and olfactory system are directly exposed to tobacco smoke in smokers and in non-smokers who live with or work around smokers. However, despite the potential for a direct impact of tobacco smoke on the nasal epithelium and olfactory neurons, no prior studies have assessed cotinine levels in nasal mucus. We sought to determine whether cotinine levels in nasal lavage fluid (NLF) would provide a reasonable estimate of smoke exposure. We assayed cotinine using a competitive immunoassay in NLF from 23 smokers, 10 non-smokers exposed to tobacco smoke (ETS) and 60 non-smokers who did not report smoke exposure. NLF cotinine levels were significantly higher in smokers than in non-smokers, regardless of their exposure to ambient tobacco smoke. Cotinine levels in this small group of exposed non-smokers were not significantly different than those of non-exposed non-smokers. A cutoff of 1 ng/ml provided a sensitivity of 91% and a specificity of 99% for smoking status in this sample. Data were consistent with self-reported smoking status, and a cutoff of 1.0 ng/ml NLF cotinine may be used to classify smoking status. While saliva is the most easily obtained body fluid, NLF can be used to provide an objective and precise indication of smoking status and more directly reflects smoke exposure in the nasal and olfactory mucosa.
Spectral studies of O2−, NO2− and CrO42− in molten LiF-NaF-KF and of O2− in liquid ammonia☆

Abstract Spectral studies of O2−, CrO42− and NO2− in molten LiF-NaF-KF at 500°C and of O2− in liquid ammonia were carried out. O2− ion exhibits a single absorption peak at 254 nm. It is, however, unstable in molten LiF-NaF-KF. In the same solvent CrO42∮- exhibits two bands at 372 and 265 nm; the molar absorptivity of the two bands are 3970 and 2940 M−1 cm−1, respectively, at 500°C. In the same molten salt solvent, NO2− exhibits a single absorption band at 365 nm. In liquid ammonia, O2− exhibits an adsorption peak at 252 nm with a molar absorptivity of approximately 3000 M−1 cm−1 at −33°C. A method for the removal of chromium ions and certain other reducible ions from molten LiF-NaF-KF is also presented.