cssi/SciSciGPT-SciSciNet huggingface dataset:
Kinetics of Escherichia coli B D-lactate dehydrogenase and evidence for pyruvate-controlled change in conformation.

Abstract Kinetic properties of d(-)-specific lactate dehydrogenase (d-lactate:diphosphopyridine nucleotide oxidoreductase, EC 1.1.1.28) from Escherichia coli B indicate the following. 1. The reaction catalyzed is essentially unidirectional, the oxidation of d(-)-lactate with diphosphopyridine nucleotide as coenzyme proceeding at only about 0.01% of the rate of pyruvate reduction. 2. The enzyme shows Michaelis-Menten kinetics for reduced diphosphopyridine nucleotide, but pyruvate activates it. 3. A lag in the rate of oxidation of the reduced diphosphopyridine nucleotide is eliminated by prior incubation with pyruvate. The duration of this lag is independent of enzyme concentration, suggesting that pyruvate causes a change in the conformation of the enzyme rather than in its state of aggregation. The identity of the molecular weight of the enzyme at a very low concentration in the absence and in the presence of the substrate confirms this finding. 4. Two lines of evidence indicate that there are two types of binding sites for pyruvate. The variation of Hill plots with pH is interpretable only in terms of two sites with different binding properties. Furthermore, the two sites bind different substrate analogues. Oxamate is an inhibitor of this enzyme, but does not substitute for pyruvate as an activator. On the other hand, α-ketobutyrate does not inhibit the catalysis but activates the enzyme, converting the substrate saturation curve from sigmoidal to hyperbolic. 5. The kinetic properties of the catalytic site appear to be similar to those of vertebrate l-lactate dehydrogenases, although the dissociation constants for both pyruvate and reduced diphosphopyridine nucleotide are considerably larger for the E. coli d-lactate dehydrogenase. 6. The kinetic properties of this enzyme are consistent with the course and regulation in vivo of pyruvate metabolism.
Insulin Degradation and Insulin‐Degrading Enzyme

The sections in this article are: 1 Historical Perspective 2 Current Model of Insulin Degradation 2.1 Insulin Clearance 2.2 Liver 2.3 Kidney 2.4 Orfier Tissues 2.5 General Cellular Processes 2.6 Enzymatic Mechanisms for Cellular Metabolism of Insulin 3 Insulin-Degrading Enzyme 3.1 General Characteristics 3.2 Molecular Characteristics 3.3 Cellular Characteristics 4 Intracellular Insulin and Insulin Action 5 Conclusions and Future Prospects
Chapter 2 Plasmalogens and O-alkyl glycerophospholipids

Publisher Summary Glycerophospholipids with ether linkages are found in nearly all animal and bacterial cells with the exception of most aerobic bacteria. In contrast to the diacyl types of glycerophospholipids, the plasmalogens contain a hydrocarbon chain attached to glycerol through a dehydrated hemiacetal (vinyl ether) linkage and the alkylacyl glycerophospholipids contain a hydrocarbon chain attached through an ether linkage. The oxidation levels of the ether-linked side-chains are aldehyde and alcohol for plasmalogens and alkylacyl glycerophospholipids, respectively. Plasmalogens are glycerophospholipids containing a potential aldehyde that were first discovered in the plasma of cells. Thus the name was derived from plasm + al + ogen. A correct common name for 1-alk-1'-enyl-2-acyl- sn -glycero-3-phosphoethanolamine is “ethanolamine plasmalogen.” Purified preparations of plasmalogens have been made by removal of the diacyl glycerophospholipids by mild alkaline hydrolysis, hydrolysis by phospholipase A 2 from snake venoms and by hydrolysis by phospholipase D from cabbage. These methods depend on the lesser reactivity of plasmalogens.
Metrics for assessment of smart grid data integrity attacks

There is an emerging consensus that the nation's electricity grid is vulnerable to cyber attacks. This vulnerability arises from the increasing reliance on using remote measurements, transmitting them over legacy data networks to system operators who make critical decisions based on available data. Data integrity attacks are a class of cyber attacks that involve a compromise of information that is processed by the grid operator. This information can include meter readings of injected power at remote generators, power flows on transmission lines, and relay states. These data integrity attacks have consequences only when the system operator responds to compromised data by re-dispatching generation under normal or contingency protocols. These consequences include (a) financial losses from sub-optimal economic dispatch to service loads, (b) robustness/resiliency losses from placing the grid at operating points that are at greater risk from contingencies, and (c) systemic losses resulting from cascading failures induced by poor operational choices. This paper is focussed on understanding the connections between grid operational procedures and cyber attacks. We first offer an example to illustrate how data integrity attacks can cause economic and physical damage by misleading operators into taking inappropriate decisions. We then focus on unobservable data integrity attacks involving power meter data. These are coordinated attacks where the compromised data is consistent with the physics of power flow, and is therefore passed by any bad data detection algorithm. We develop metrics to assess the economic impact of these attacks under operator re-dispatch decisions using optimal power flow methods. These metrics can be used to prioritize the adoption of appropriate countermeasures including PMU placement, encryption, hardware upgrades, and advanced detection algorithms.
Comment on "Crises in Competitive versus Monopolistic Banking Systems"

This paper (Boyd, De Nicolo, and Smith 2004, this issue of JMCB) is intended as a contribution to the now-burgeoning literature on the causes and effects of banking crises. This literature has proven to be rich in theoretical and empirical content and also has potential policy relevance (see, for example, Allen and Gale 2000). Although the term "banking crisis" has a distinctly different connotation from "bank failure"-in that the former refers to a systemic panic and the latter to an individual bank failure-these terms have often been used interchangeably in the literature in the context of "representative bank" models.1 This paper too belongs to the genre of representative bank models. The paper poses two broad questions: (1) Is the probability of a banking crisis higher in a competitive or monopolistic banking system and how does the inflation rate affect these probabilities? (2) What are the probabilities of real output losses in competitive and monopolistic banking systems? To address these questions, the paper develops a standard intertemporal risksharing model with risk-averse depositors, who face a relocation/preference shock, to rationalize banks as insurance providers in a monetary, general equilibrium setting.
Orbital granulocytic sarcoma in an elderly patient.

Purpose To report a 71-year-old woman with acute myelogenous leukemia in remission who developed orbital granulocytic sarcoma. Methods The patient was referred for acute proptosis and decreased vision of the right eye. Computed tomography of the orbits demonstrated a right extraconal mass compressing the optic nerve. A right lateral orbitotomy was performed, and a portion of the mass was excised for diagnostic purposes and orbital decompression. Results Histopathologic and immunohistochemical evaluation disclosed orbital granulocytic sarcoma. With chemotherapy and radiation, vision remained stable and right proptosis resolved. Conclusions Orbital granulocytic sarcoma is usually diagnosed in children with a history of acute myelogenous leukemia. This case demonstrated that this entity may also occur rarely in older patients with a history of acute myelogenous leukemia.
Growth of well ordered Rh overlayers on Si surfaces: A field ion microscope study

Abstract Well ordered Rh overlayers have been grown on Si tip surfaces in ultrahigh vacuum. The field ion images of the overlayers grown on the Si{012} plane reveal two distinctive atomic structures. One has a diamond structure with an angle of 76° ± 2° and one has a rhombic structure with an angle of 66° + 2°. The former fits well to the atomic structure of the Rh layer of the RhSi(110) plane and the latter fits well to the structure of the Si(012) plane.
Optimal micropattern dimensions enhance neurite outgrowth rates, lengths, and orientations.

Micropattern dimensions can significantly influence neurite outgrowth orientation, rate, and length. Laminin micropatterns of various widths from 10 to 50 μm at 10 μm intervals separated by 40 μm spaces were generated on poly(methyl methacrylate) surfaces using microscale plasma-initiated patterning (μPIP). Dissociated dorsal root ganglion (DRG) neurons were seeded on the micropatterned surfaces and cultured for 24 h in serum-free media. Neurite outgrowth numbers, lengths, rates, and orientations were measured on all micropatterned substrates. The results indicated that the dimension of the laminin pattern influenced the neurite outgrowth length, rate, and orientation, but not the numbers of neurite outgrowth. Neurons on more than 30 μm wide laminin pattern showed faster neurite outgrowth compared to other dimensions, and relatively low orientation at 50 μm pattern dimensions. Neurites at 40 μm laminin pattern widths demonstrated the fastest outgrowth rates and were highly oriented. The 40 μm laminin dimension is wide enough to provide sufficient laminin amounts for neuron growth and narrow enough to efficiently guide neurites. Based on these results, adhesive protein micropatterns of 40 μm dimensions are recommended when investigating DRG neurons.
Conformational study of 1,2-dithiacyclononane☆

Abstract The temperature dependence of the Raman spectrum of 1,2-dithiacyclononane (1,2-DTCN) in the SS stretching region has been used to infer the existence of a conformational equilibrium with Δ H 0 = 5.0 ± 0.8 kJ/mol. Molecular mechanics calculations predict a (2 2 5)- C 2 lowest energy conformation in equilibrium with a (2 3 4) structure. The fully decoupled 13 C NMR spectrum at −80°C and the Raman spectra are consistent with this postulate. The temperature dependence of the 1 H NMR spectrum of 1,2-DTCN is characteristic of the ring inversion process. A crude lineshape analysis allows us to calculate Δ G 0 = 49.0 ± 1.2 kJ/mol.
Electron-Energy-Loss Study of Stage-1 Potassium- Intercalated Graphite

Electron-energy-loss spectra of stage-1 K-intercalated graphite single crystals were obtained with a scanning transmission electron microscope. The complex dielectric function with electric polarization perpendicular to the $c$ axis was derived by Kramers-Kronig analysis. The energy-loss peak at 2.5 eV is consistent with previous optical measurements, while the splitting of the one at 27 eV can be interpreted by folding the Brillouin zone of pristine graphite. Splittings and shifts of the interband transitions were observed and compared with calculations.
Mechanical Properties of Injured Human Cervical Spine Ligaments and Corresponding Effect on Spinal Kinematics

The assessment of cervical spine instability following traumatic injury is controversial [1, 4, 5, 8]. Typical definitions of cervical instability are based on the presence of several key detectable injuries using simple radiographs, computed tomography (CT), and magnetic resonance (MR) imaging. Although these imaging modalities have been shown to be relatively reliable for detection of fractures and very large soft tissue injuries, they are largely deficient for determining the presence of smaller soft tissue injuries, such as hyperstrained ligaments [1, 3]. Soft tissue injuries of this nature may be revealed with dynamic range of motion (ROM) assessment, such as a flexion and extension test with radiography. However, these tests are currently inadequate for determining the existence of specific injuries. Cervical soft tissue injuries demand further analysis, given the risk of severe and permanent neurological impairment that may accompany these injuries [2, 5].© 2011 ASME
Unregulated research with human subjects.

(1999). Unregulated research with human subjects. Accountability in Research: Vol. 6, No. 3, pp. 205-214.
From complex data to actionable information: Institutional research supporting enrollment management

Enrollment management data must be transformed into information that is accessible, timely, and meaningful. Creative approaches are suggested to overcome the challenges of oversimplification and of reports too complex to be useful.
State-Sponsored Social Control of Illegitimate Social Movements: Strategies Used to Financially Damage Radical Islamic, Terrorist-Labeled Organizations

This article documents strategies and tactics of social control used by the U.S. government to detect and deter financing of radical Islamic, terrorist-labeled organizations. Through grounded theory, social control strategies were identified based on data from congressional committee hearings from 1999 to 2011. Findings revealed the presence of nine such strategies: (1) discover sources of funding, (2) deny or restrict access to money, (3) establish information networks and communication norms, (4) create derogatory labels, (5) influence the media, (6) impose legal sanctions, (7) offer financial incentives, (8) construct a shared collective identity, and (9) force terrorist-labeled organizations on the defensive.
How does reactivity affect police behavior? Describing and quantifying the impact of reactivity as behavioral change in a large-scale observational study of police

Critics have challenged the face validity of police observational data by arguing that officers will react to the presence of the observer. This article examines the descriptive accounts of reactivity from the Project on Policing Neighborhoods (or POPN) to: (1) describe reactivity as behavioral change (i.e., officers who are more or less proactive), (2) identify why officers react in this manner, and (3) specify officer behavior susceptible to this form of reactivity. Additional analyses indicate that officers are 5.3 times more likely to be more versus less proactive. Officers are also more proactive during early stages of fieldwork and when accompanied by female observers. Finally, there is evidence of an interaction effect between time in the field and observer sex where officers are 4.5 times more likely to be more proactive during early stages of fieldwork when accompanied by female observers. The more general implications of the findings are also discussed.
Congenital Adrenal Hyperplasia in Birmingham: a Retrospective Analysis (1958–1985)

Recent estimates of the prevalence of congenital adrenal hyperplasia (CAH) are 1 in 8000–9000 by neonatal screening (Cacciari et al., 1983) and 1 in 12000–13000 by case report (Murtaza et al., 1980; Werderetjal., 1980). Up to two thirds of the cases suffer from the more severe salt-losing form of the disease (Murtaza et al., 1980; Werder et al., 1980; Lebovitz et al., 1984).
Effects of ICV administration of the alpha1A-adrenoceptor antagonist 5-methylurapidil on concurrent measures of eating and locomotion after cocaine in the rat.

Abstract Psychostimulants including amphetamine and cocaine induce locomotion and stereotypy and suppress eating. Although the capacity of cocaine to alter locomotion is usually viewed as related to dopamine neurotransmission, recent studies suggest that norepinephrine, acting through alpha1-adrenergic receptors (α1-ARs) can facilitate cocaine-stimulated locomotion. Of the three α1-AR subtypes (α 1A , α 1B , and α 1D ) identified to date, inactivation of the α 1B -AR subtype diminishes cocaine-stimulated locomotion, whereas the impact of inactivation of the α 1A -AR subtype on either eating or locomotion is unknown. In the present study, we assessed the relative impact of ICV administration of the α 1B -AR antagonist 5-methylurapidil (5-MU) on cocaine-stimulated hyperlocomotion and hypophagia, using a concurrent method [Wellman, P.J., Ho, D.H., Davis, K.W., 2005. Concurrent measures of feeding and locomotion in rats. Physiology of Behavior 84 (5), 769–774.]. Rats were infused ICV with one of 3 doses of 5-MU (0, 3, or 30 nmol) and then injected (i.p.) with 0, 2.5, 5.0, 10.0, or 20.0 mg/kg cocaine HCl on each of five tests. Rats always received the same 5-MU dose, but a different cocaine dose on each trial. Feeding and locomotion were assessed concurrently during a 45-min postinjection period. Significant suppression of eating was noted at 2.5 mg/kg cocaine, a dose that does not alter forward locomotion in the rat. Administration of 5-MU did not alter locomotion in rats treated with saline, but did significantly increase baseline food intake. Neither cocaine-induced hypophagia nor hyperlocomotion was altered by ICV administration of 5-MU. These results suggest that the capacity of α1-AR agonists (e.g. phenylpropanolamine) to suppress eating may be related to activation of the α 1A -AR subtype, whereas cocaine does not act through the α 1A -AR subtype to suppress eating nor does this subtype modulate cocaine-induced hyperlocomotion.
Design of a gas tight water sampler for AUV operations

This paper presents the design and preliminary test results for a small gas tight water sampler intended to work on scientific AUVs. In recent years AUVs have developed into reliable platforms capable of carrying a wide variety of environmental sensors for in-situ chemical measurements. Physical sample collection however remains difficult, due to the combination of space, power and complexity constraints inherent in working with autonomous platforms. The AUV sampler is a small (12 cm times 85 cm) cylindrical package designed to collect eight 20 ml gas tight volumes of water, with each sample maintained at high pressure to depths of 2000 meters. The motivation behind this device is to provide high quality autonomous water sample collection and return for accurate analysis of dissolved chemicals without degassing. Additionally the system can be used to ground truth in-situ chemical measurements.
Self-tolerance and autoimmunity

Studies of self-tolerance and autoimmunity have moved rapidly into new arenas. These include the definition of at least two mechanisms for tolerance induction in both T and B cells, the creation of new disease-susceptible strains such as the HLA-B27 transgenic rats, the creation of new disease-resistant strains such as I-E or I-Ak NOD transgenic mice, and the precise definition of both antigen and antigen receptor for pathogenic lymphocytes in some models. More effective therapies for autoimmune disease should result from the knowledge gained.
Natural sunlight and its association to civil aviation accidents

Background Glare is a temporary visual sensation produced by luminance within the visual field that is significantly greater than that to which the eyes are adapted. Glare from natural and artificial light sources can result in temporary visual impairment, increasing the risk of an accident. This study investigates the relationship between visual impairment from natural sunlight and aviation accidents. Methods The National Transportation Safety Board Aviation Accident/Incident Database was queried for the period January 1,1988 to December 31,1998 for terms, which included “sun”, “glare”, “vision”, “blinded”, and “reflections”. Reports annotated with one or more of these terms were reviewed to determine whether glare was considered a direct or contributing factor in the event. Results There were 130 accidents in which glare was found to be a contributing factor. The majority of these events occurred during clear weather and atmospheric conditions (85%), and were associated with approach/landing and take-off/departure phases of flight (55%). Conclusions Exposure to glare from natural sunlight has contributed to aviation accidents, primarily under otherwise optimal visual conditions at low altitude in congested airspace. Preventative techniques are presented that may protect a pilot's visual performance against the debilitating effects of glare from the sun.
Developing Organization of Mental Verbs: Evidence for the Development of a Constructivist Theory of Mind in Middle Childhood

Abstract Two experiments examined the development of a theory of mind in middle childhood by examining changes in the organization of mental verbs of knowing. In both experiments, children and adults rated the similarity of pairs of mental verbs in terms of the way they felt they used their mind in each one. Experiment 1 used thirty-six 8- and thirty-four 10-year-olds, and 27 adults. In Experiment 2, 9- and 11-year-old children were classified according to their cognitive monitoring ability (Markman, 1981). Fifteen cognitive monitoring and 15 nonmonitoring children were used, and 33 adults also participated. Multidimensional scaling (MDS) analyses of each group's ratings indicated that participants distinguished mental verbs according to the certainty aspects and information processing aspects of mental activity. Older children and comprehension monitors placed greater emphasis on the certainty aspects of mental activity than younger children and comprehension nonmonitors. It is concluded that important aspects of a constructivist theory of mind develop during middle childhood.
State variables for linear multivariable systems with multiple eigenvalues

This paper presents a technique which utilizes the state-variable approach to analyze the performance of a multivariable system with multiple eigenvalues. This technique is believed to be better than other proposed ones in its simplicity in obtaining the solution.
DOUBLY STOCHASTIC HILBERTIAN PROCESSES

In this paper, we consider a Hilbert-space-valued autoregressive stochastic sequence (X n ) with several regimes. We suppose that the underlying process (I n ) which drives the evolution of (X n ) is stationary. Under some dependence assumptions on (I n ), we prove the existence of a unique stationary solution, and with a symmetric compact autocorrelation operator, we can state a law of large numbers with rates and the consistency of the covariance estimator. An overall hypothesis states that the regimes where the autocorrelation operator's norm is greater than 1 should be rarely visited.
Use of brainstem flat-mounts for visualizing DiI-filled axons in the developing rodent visual system

The lipophilic carbocyanine fluorescent label DiI was injected in one eye of aldehyde-fixed embryonic or postnatal hamsters and the brains were examined using flat-mounts of the chiasm region, of the lateral surface of the brainstem, or of the midbrain tectum. Single axons could be discerned within the optic nerves and along the optic tract. Many fibers were tipped by growth cones, ending at various levels of the brainstem. Fine details of retinofugal axon morphology, including varicosities, branch-points and filopodial extensions on growth cones were visible in the flat-mounts. Such preparations allow a high-resolution view of labeled axons which course near the surface of the brain. It is possible, with this method, to simultaneously examine the morphogenesis of multiple collateral arbors on single fibers which project to more than one terminal zone.
Depressive symptoms among elderly residents of public housing: a follow-up study.

second study, 11 of these subjects again had scores greater than 16 (the depressed-depressed group), and 16 had scores less than 16 (the de pressed-nondepressed group). A total of 97 subjects had scores less than 16 at the time ofthe first study. One year later, ten ofthese subjects had scores greater than 16 (the non depressed-depressed group), and 87 had scores less than 16 (the non depressed-nondepressed group). Highly significant differences in mean (CES-D) scores between the groups were found at the time of the first study (F=95.8, df=3,120, p< .0001) and again one year later (F = 69.13, df= 3,120, p<.000l). For the remainder ofthe analysis, subjects with CES-D scores greater than 16 both at the time of the first study and one year later were clas sified as having persistent depression (N = 11). Subjects with scores great
Comparative studies on pharmacokinetics and metabolism of the anti-juvenile hormone precocene II

The cuticular penetration and pharmacokinetics of the anti-juvenile hormone precocene II were determined in a sensitive species (Oncopeltus fasciatus) and an insensitive species (Heliothis zea). Precocene was sequestered by the fat body and slowly metabolized in Oncopeltus, but rapidly metabolized and excreted in Heliothis. Studies in vitro using inhibitors for cytochrome P-450 and for cyt P-450-NADPH-reductase, confirmed the anticipated detoxification of precocene by a mixed-function oxidase via the 3,4-epoxide. Use of the inhibitors in vivo had no influence on the metabolism of precocene.
Cultural influences on positive father involvement in two-parent mexican-origin families

A growing body of research documents the importance of positive father involvement in children's development. However, research on fathers in Latino families is sparse, and research contextualizing the father-child relationship within a cultural framework is needed. The present study examined how fathers' cultural practices and values predicted their fifth-grade children's report of positive father involvement in a sample of 450 two-parent Mexican-origin families. Predictors included Spanish- and English-language use, Mexican and American cultural values, and positive machismo (i.e., culturally related attitudes about the father's role within the family). Positive father involvement was measured by the child's report of his or her father's monitoring, educational involvement, and warmth. Latent variable regression analyses showed that fathers' machismo attitudes were positively related to children's report of positive father involvement and that this association was similar across boys and girls. The results of this study suggest an important association between fathers' cultural values about men's roles and responsibilities within a family and their children's perception of positive fathering.
QUANTITATIVE ANALYSIS OF INFRARED CONTRAST ENHANCEMENT ALGORITHMS

Dynamic range reduction and contrast enhancement are two image-processing methods that are required when developing thermal camera systems. The two methods must be performed in such a way that the high dynamic range imagery output from current sensors are compressed in a pleasing way for display on lower dynamic range monitors. This research examines a quantitative analysis of infrared contrast enhancement algorithms found in literature and developed by the author. Four algorithms were studied, three of which were found in literature and one developed by the author: tail-less plateau equalization (TPE), adaptive plateau equalization (APE), the method according to Aare Mallo (MEAM), and infrared multi-scale retinex (IMSR). TPE and APE are histogram-based methods, requiring the calculation of the probability density of digital counts within an image. MEAM and IMSR are frequency-domain methods, methods that operate on input imagery that has been split into components containing differing spatial frequency content. After a rate of growth analysis and psychophysical trial were performed, MEAM was found to be the best algorithm.
T-matrix computations of light scattering by large nonsperical particles: recent advances

In this paper we discuss the application of the T-matrix approach to rigorously compute light scattering by polydisperse, randomly oriented nonspherical particles with sizes comparable to and larger than wavelengths of observation. First, we describe an efficient method for suppressing the numerical instability of the regular T-matrix approach in computations for spheroids and finite cylinders with size parameters larger than about 25. Second, we describe how the T-matrix approach can be used to rigorously compute the scattering of light by randomly oriented two-sphere aggregates (bispheres). Both methods are extremely efficient, are applicable to scatterers with equivalent-sphere size parameters exceeding 50, and are especially suitable in computations for polydisperse particles. We report results of numerical computations that demonstrate the capabilities of the two methods and are used to discuss the effects of particle nonsphericity on light scattering.
Isolation and identification of the multiple forms of soybean phytases

Sequential precipitation with polyethylene glycol (PEG) and KCl followed by preparative anion exchange high-performance liquid chromatography was used to isolated acid phosphatases (APases) from germinating soybean seeds. KCl inhibited the PEG precipitation of APases. Thus individual APases can be isolated directly from crude extracts by controlling PEG and KCl concentrations. Four of the isolated APases were phytases. APases 3 and 5 exhibited optimal activity at pH 4.5 and and 5.8. Phytase activity was at its peak at 40°C for APase 4 and at 60°C for APases 3, 5, and 6. This isolation method can be used to identify endogenous and/or exogenous phytases that are suitable for phytic acid hydrolysis in many food and feed systems, especially during the processing. of oilseeds and cereal-based ingredients.
Nuclear data sheets for A = 114

Experimental nuclear structure information through February 1975 are compiled, and adopted properties are presented. Where possible, the data are presented in comparative level diagrams, thereby eliminating many tabular listings, which resulted in substantial reduction in the size of the compilation.
Adult Male Replacement in Socially Monogamous Equatorial Saki Monkeys (Pithecia aequatorialis)

Sakis (genus Pithecia) commonly live in socially monogamous groups, but data from wild populations on group dynamics and on the turnover of reproductive-age animals are rare. Here we describe the replacement of the adult male in one group of sakis in the Ecuadorian Amazon following the death of the initial resident. We use 354 h of focal behavioral data to describe differences in the spatial relationships among group members before and after the replacement and to examine changes in the rate of male-to-female grooming, aggression, scent marking and vocalization. Interactions with extra group individuals within the group's home range were more frequent during and after the replacement than before. The presence of such additional animals during periods of reproductive turnover may explain at least some reported observations of saki groups with more than 1 reproductive-age male or female.
Functional and ecological xylem anatomy

Abstract Cohesion-tension transport of water is an energetically efficient way to carry large amounts of water from the roots up to the leaves. However, the cohesion-tension mechanism places the xylem water under negative hydrostatic pressure ( P x ), rendering it susceptible to cavitation. There are conflicts among the structural requirements for minimizing cavitation on the one hand vs maximizing efficiency of transport and construction on the other. Cavitation by freeze-thaw events is triggered by in situ air bubble formation and is much more likely to occur as conduit diameter increases, creating a direct conflict between conducting efficiency and sensitivity to freezing induced xylem failure. Temperate ring-porous trees and vines with wide diameter conduits tend to have a shorter growing season than conifers and diffuse-porous trees with narrow conduits. Cavitation by water stress occurs by air seeding at interconduit pit membranes. Pit membrane structure is at least partially uncoupled from conduit size, leading to a much less pronounced trade-off between conducting efficiency and cavitation by drought than by freezing. Although wider conduits are generally more susceptible to drought-induced cavitation within an organ, across organs or species this trend is very weak. Different trade-offs become apparent at the level of the pit membranes that interconnect neighbouring conduits. Increasing porosity of pit membranes should enhance conductance but also make conduits more susceptible to air seeding. Increasing the size or number of pit membranes would also enhance conductance, but may weaken the strength of the conduit wall against implosion. The need to avoid conduit collapse under negative pressure creates a significant trade-off between cavitation resistance and xylem construction cost, as revealed by relationships between conduit wall strength, wood density and cavitation pressure. Trade-offs involving cavitation resistance may explain the correlations between wood anatomy, cavitation resistance, and the physiological range of negative pressure experienced by species in their native habitats.
Substructure boosts to dark matter annihilation from Sommerfeld enhancement

The recently introduced Sommerfeld enhancement of the dark matter annihilation cross section has important implications for the detection of dark matter annihilation in subhalos in the Galactic halo. In addition to the boost to the dark matter annihilation cross section from the high densities of these subhalos with respect to the main halo, an additional boost caused by the Sommerfeld enhancement results from the fact that they are kinematically colder than the Galactic halo. If we further believe the generic prediction of the cold dark matter paradigm that in each subhalo there is an abundance of substructure which is approximately self-similar to that of the Galactic halo, then I show that additional boosts coming from the density enhancements of these small substructures and their small velocity dispersions enhance the dark matter annihilation cross section even further. I find that very large boost factors (${10}^{5}$ to ${10}^{9}$) are obtained in a large class of models. The implications of these boost factors for the detection of dark matter annihilation from dwarf spheroidal galaxies in the Galactic halo are such that, generically, they outshine the background gamma-ray flux and are detectable by the Fermi Gamma-ray Space Telescope.
David H. Hubel (1926–2013)

On 22 September, David Hunter Hubel died at his home in Lincoln, Massachusetts. He was 87. We have lost one of the great neuroscientists of the 20th century, whose work revealed the beautifully ordered activity of single neurons in the visual cortex and how these neurons might be assembled to ultimately produce vision. We have also lost the most innovative, enthusiastic, and witty person you could ever meet.
Urchin Lytechinus variegatus Grazing on Eelgrass, Zostera marina

The urchin,Lytechinus variegatus, when feeding on eelgrass,Zostera marina, produces small, 1–2 mm, particles of the plant material which may accelerate the rate of decomposition. No significant difference was noted in the Mn, Fe, Cu, and Zn content of green eelgrass blades compared to recently voided urchin fecal material derived from eelgrass.
Familial Sudden Cardiac Death Associated with a Terminal QRS Abnormality on Surface 12‐Lead Electrocardiogram in the Index Case

Familial Sudden Death and ECG Abnormalities. A case is presented of an 18-year-old male who had been resuscitated following an episode of sudden death due to ventricular fibrillation. The patient was noted to have an abnormal deflection in the terminal QRS on surface ECG and an abnormal signal-averaged KCG demonstrating a late potential coincident with the terminal QRS abnormality on the ECG. The patient had easily inducible polymorphic ventricular tachycardia during electrophysiologic study, which was suppressed by quinidine but not by procainamide or beta blockers. The surface ECG and signal-averaged ECG also were normalized by quinidine but not by procainamide or beta blockers. The patient had no further arrhythmias on quinidine for 6 years until he inexplicably discontinued his medication and died suddenly shortly thereafter. The present case may represent a unique familial sudden death syndrome or possibly a variant of the sudden death syndrome associated with right bundle branch block and ST elevation in V1, through V3, Currently available data suggest that, in such patients, an implantable cardioverter defibrillator may provide better protection from sudden death than does antiarrhythmic drug therapy.
Antigen activation of human B lymphocytes bearing artificial antigen receptors.

Abstract When highly purified human and murine B cells are challenged in vitro with certain so called “T cell-independent” activators such as the polyclonal B cell activator lipopolysaccharide (LPS) or the clonally specific B cell activator dinitrophenyl-conjugated polymerized flagellin (DNP-POL), mouse, but not human, cells differentiate into immunoglobulin-secreting cells. However, results from this study show that DNP-POL can cause human B cell differentiation in a T cell-independent manner when the antigen is concentrated onto the cells via artificially incorporated palmitate-modified anti-DNP mouse IgA molecules. This response is comparable in magnitude to that induced by a T cell-dependent polyclonal B cell activator, pokeweed mitogen, in unfractionated mononuclear cell cultures, suggesting that DNP-POL induced polyclonal B cell differentiation. DNP-POL binding to the artificial receptor molecules on B cells did not cause cellular proliferation, even in unfractionated mononuclear cell populations. These results are similar to those obtained in previous studies using mouse B cells in which the artificial receptor was unable to act as a transmembrane signaling element. From these studies, we conclude that B cells express clonally unrestricted, presumably low-avidity, endogenous receptor for POL, and that signaling through this receptor activates B cell differentiation but not cell proliferation.
Detergent Fractionation of Glutaraldehyde-fixed Spinach Thylakoids

In 1969, Hallier and Park (5) showed that glutaraldehydefixed spinach thylakoids retained appreciable Hill reaction activity after extraction with 1% Triton X-100. The resistance of the fixed membranes to detergent destruction led them to suggest that such membranes might be favorable starting material for subsequent detergent fractionation studies. They postulated that cross-linking of membrane proteins would allow isolation of the larger membrane subunits identified by electron microscopy (8, 9). This paper reports an exploration of this suggestion. We investigated whether fixed membranes fragment differently from unfixed membranes when treated with various detergents and whether the fragments so liberated could be related morphologically to structures observed in the intact thylakoid.
REDD+ and the Indigenous Question: A Case Study from Ecuador

One of the main issues regarding the implementation of REDD+ in Latin America has been the growing concern that such projects may infringe upon the rights and negatively affect the livelihoods of forest-dependent communities. Various indigenous and civil society organizations are ardently opposed to the initiative. Such is the case in Ecuador, where indigenous opposition to REDD+ represents a considerable obstacle in the creation of a national strategy since more than 60% of the country’s remaining forest cover is on indigenous land or under indigenous occupation. Thus one of the most critical challenges remaining for Ecuador will be the construction of a strong legal, financial, and institutional framework—one that the greater indigenous community might be willing to accept. Closer examination of this topic however, reveals just how difficult this may become. Lack of information, a recent political split between national authorities and the indigenous sector, and the dissimilar organizational capacity levels of indigenous communities make the feasibility of carrying out REDD+ projects on these lands extremely complex. However, the biggest obstacle may be ideological. Many indigenous groups view REDD+, with its possible emphasis on international markets and neoliberal mechanisms, as a continuation of the type of policies that have impeded their quest for sovereignty and self determination. As such, indigenous people are only willing to consider such projects if they clearly see preconditions in place that would safeguard their cultures, territories, and autonomy.
Mechanistic studies of the reaction of reduced methane monooxygenase hydroxylase with dioxygen and substrates

Soluble methane monooxygenase (sMMO) catalyzes the oxidation of methane to methanol. Single-turnover reactions of sMMO from Methylococcus capsulatus (Bath) were studied by stopped-flow optical spectroscopy to examine further the activated dioxygen intermediates and their reactions with hydrocarbon substrates. A diiron(III) peroxo species designated H{sub peroxo} is the first intermediate observed in the reaction between the chemically reduced hydroxylase (H{sub red}) and dioxygen. The optical spectrum of this species determined by diode array detection is presented for the first time and exhibits visible absorption bands with {lambda}{sub max} {approx} 420 nm ({epsilon} = 4,000 M{sup {minus}1} cm{sup {minus}1}) and {lambda}{sub max} = 725 nm ({epsilon} = 1,800 M{sup {minus}1} cm{sup {minus}1}). The temperature dependences of the rate constants for formation and decay of H{sub peroxo} and for the subsequent intermediate, Q, were examined in the absence and in the presence of hydrocarbon substrates, and activation parameters for these reactions were determined. For single-turnover reaction kinetics monitored at 420 nm, the {lambda}{sub max} for Q, a nonlinear Eyring plot was obtained when acetylene or methane was present in sufficiently high concentration. This behavior reflects a two-step mechanism, Q formation followed by Q decay, in which the rate-determining step changes depending on themore » temperature. The rate of H{sub peroxo} formation does not depend on dioxygen concentration, indicating that an effectively irreversible step involving dioxygen precedes formation of the diiron(III) peroxo species. The rate constant observed at 4 C for H{sub peroxo} formation, 1--2 s{sup {minus}1}, is slower than that determined previously by Moessbauer and optical spectroscopy, {approximately}20--25 s{sup {minus}1} (Liu, K. E., et al. J. Am. Chem. Soc. 1995, 117, 4997--4998; 10174--10185). Possible explanations for this discrepancy include the existence of two distinct peroxo species. Intermediate Q exhibits photosensitivity when monitored by diode array methodology, a property that may arise from enhanced reactivity of a transient charge-transfer species. The photoreaction can be avoided by using a monochromator to obtain kinetics data at single wavelengths. The reactions of substrates with intermediate species were studied by single- and double-mixing stopped-flow spectroscopy. The Q decay rate exhibits an approximate first-order dependence on substrate concentration for a wide range of hydrocarbons, the relative reactivity varying according to the sequence acetylene > ethylene > ethane > methane > propylene > propane. In addition, the data indicate that H{sub peroxo} can oxidize olefins but not acetylene or saturated hydrocarbons.« less
FUNCTIONAL DIFFERENCES BETWEEN THE OUTER AND INNER ZONES OF THE GUINEA PIG ADRENAL CORTEX

The guinea pig adrenal cortex is grossly composed of two regions: an outer, yellow zone and an inner, brown zone. These zones,which represent 33% and 66% of the total adrenocortical volume,respectively,can be separated by blunt dissection. It has been previously reported that specific pregnenolone and pregnenolone sulfate binding proteins are present in the high speed supernatant fraction (cytosol) prepared from the whole adrenal cortex of the. guinea pig. However, when cytosol was prepared from the separate outer and inner cortical zones, it was found that the steroid-binding proteins were concentrated in the inner zone. This correlated with the level of pregnenolone which was significantly greater in the cytosol of the inner zone where greater than 50% was found to be bound. In contrast, the concentration of cortisol was 30 times greater in the cytosol of the outer cortical zone and less than 4% was found to be bound. These data suggest that cortisol is produced primarily in the outer cortical zone, a e...
Visual acuity as a reinforcement in learning to control pupil size

Abstract Cervical sympathectomy was performed unilaterally on twenty-three cats and bilaterally on five cats. In one experiment we measured the size of the normal pupil which is known to dilate consensually after unilateral sympathectomy. The change in size of the normal pupils of eight cats housed together in a large, well-lighted room was compared with that of seven cats housed separately in dimly lighted cages. One week postoperatively the return to normal size from postoperative dilation was further advanced in the free-ranging animals than in the caged ones. In another experiment, where the interest was in the changes in size of the sympathectomized pupil, five cats with bilateral cervical sympathectomy had more nearly recovered normal pupil size 2 weeks after surgery than had fifteen cats with unilateral sympathectomy, although the treatment of the two groups was identical in other respects. We interpret the differences between the groups in both experiments as being results of learning in the autonomic nervous system, the reinforcement being the improvement in visual acuity resulting from random fluctuations in the size of the pupil. In the first experiment these fluctuations were produced more frequently in the free-ranging animals than in the caged ones. In the second experiment increased visual acuity was more reinforcing for the animals with bilateral sympathectomy than for the unilateral ones, for the former could not rely upon almost normal vision in an unoperated eye.
Selenium derivatization of nucleic acids for crystallography

The high-resolution structure of the DNA (5′-GTGTACA-C-3′) with the selenium derivatization at the 2′-position of T2 was determined via MAD and SAD phasing. The selenium-derivatized structure (1.28 A resolution) with the 2′-Se modification in the minor groove is isomorphorous to the native structure (2.0 A). To directly compare with the conventional bromine derivatization, we incorporated bromine into the 5-postion of T4, determined the bromine-derivatized DNA structure at 1.5 A resolution, and found that the local backbone torsion angles and solvent hydration patterns were altered in the structure with the Br incorporation in the major groove. Furthermore, while the native and Br-derivatized DNAs needed over a week to form reasonable-size crystals, we observed that the Se-derivatized DNAs grew crystals overnight with high-diffraction quality, suggesting that the Se derivatization facilitated the crystal formation. In addition, the Se-derivatized DNA sequences crystallized under a broader range of buffer conditions, and generally had a faster crystal growth rate. Our experimental results indicate that the selenium derivatization of DNAs may facilitate the determination of nucleic acid X-ray crystal structures in phasing and high-quality crystal growth. In addition, our results suggest that the Se derivatization can be an alternative to the conventional Br derivatization.