cssi/SciSciGPT-SciSciNet huggingface dataset:
Picosecond photolysis of azo compounds in liquid alkanes: germinate recombination kinetics for polyatomic free radical pairs

Abstract Picosecond optical absorption transients for the photolysis products of azocumene and the cyclic azo compound 3,8-diphenyl-1,2-diaza-1-cyclooctene have been measured in a series of alkane solvents having different liquid viscosities. The transient intermediate produced from azocumene decays through a diffusion influenced process which is interpreted as secondary recombination of geminate free radical pairs. This assignment is based on the wavelength dependence of the transient absorption signal, the viscosity dependence of the decay kinetics and the complementary decay profiles seen for free and tethered radical pairs. The long time limit of the survival probability for geminate cumyl free radicals follows the reciprocal square root fo time decay predicted by the Smoluchowski diffusion equation.
Efficient plant regeneration of native spearmint (Mentha spicata L.)

Protocols and media constituents for efficient in vitro plant regeneration of Native Spearmint (Mentha spicata L. cultivar ‘Native Spearmint’) have been defined. Adventitious shoots were initiated either directly from morphogenetically competent cells of explants or primary callus. Leaf explants from at least 2-mo.-old in vitro-maintained shoots exhibited the greatest morphogenetic capacity. Explants derived from basal portions of leaves at the bottom of the shoot were most responsive, with up to a 100% regeneration frequency and greater than nine shoots per explant. Highest frequency of meristemoids and morphogenetic callus were initiated from explants cultured onto a basal medium containing Murashige and Skoog (MS) salts, supplemented with 4 mg thidiazuron (TDZ) per L and 25% (vol/vol) coconut water (CW) for 10 to 14 d in darkness. Bud and shoot development required removal of both TDZ and CW from the medium. Shoot propagules were transferred to basal medium supplemented with 0.01 mg α-naphthaleneacetic acid (NAA) per L and grown under low light for about 2 wk to facilitate shoot elongation. Individual shoots about 1 cm tall were dissected and retransferred onto the same medium. Root initiation began within 4 to 6 d and a functional root system developed within 2 to 3 wk. These plantlets were transferred to soil and acclimated successfully for growth and development in a greenhouse. This is the first report of an efficient regeneration system for Native Spearmint based on adventitious organogenesis.
Impulse based dynamic rolling in the Rolling Disk Biped

This paper explores the use of pushing off the ground to produce dynamic rolling for the Rolling Disk Biped (RDB). An open loop controller is used that periodically opens joints to kick off the ground to begin and continue rolling motions. This impulse based method of propulsion is suited to robots that have limited control of the center of gravity, or to robots that do not always form a continuous rolling surface. Hybrid mobility robots can use this method of rolling in order to utilize multiple modes of locomotion such as rolling and walking. Both simulations and experiments show that the use of impulse based rolling in the RDB can initiate rolling from a variety of initial conditions and can produce continuous rolling three times faster than center of gravity based rolling. The general impulse method presented can be used for some existing robots and will help in creating new hybrid mobility robots.
A spatiotemporal decomposition strategy for personal home video management

With the advent and proliferation of low cost and high performance digital video recorder devices, an increasing number of personal home video clips are recorded and stored by the consumers. Compared to image data, video data is lager in size and richer in multimedia content. Efficient access to video content is expected to be more challenging than image mining. Previously, we have developed a content-based image retrieval system and the benchmarking framework for personal images. In this paper, we extend our personal image retrieval system to include personal home video clips. A possible initial solution to video mining is to represent video clips by a set of key frames extracted from them thus converting the problem into an image search one. Here we report that a careful selection of key frames may improve the retrieval accuracy. However, because video also has temporal dimension, its key frame representation is inherently limited. The use of temporal information can give us better representation for video content at semantic object and concept levels than image-only based representation. In this paper we propose a bottom-up framework to combine interest point tracking, image segmentation and motion-shape factorization to decompose the video into spatiotemporal regions. We show an example application of activity concept detection using the trajectories extracted from the spatio-temporal regions. The proposed approach shows good potential for concise representation and indexing of objects and their motion in real-life consumer video.
Properties of selected subset diagnostics in regression

Abstract Anomalies are cited in the use of subset regression diagnostics. Two leverage diagnostics are unified through canonical leverages . Other diagnostics relate one-to-one with the R -Fisher statistic, supporting exact but equivalent tests at level α . Three distance diagnostics exhibit ad hoc scalings; their distributions are characterized and ordering properties noted; one is studied further through simulation; and a properly scaled version is given. Case studies reexamine the use of selected subset diagnostics in practice.
Lipids of seven cereal grains

Grain samples of representative varieties of barley, corn, oats, rye, sorghum, triticale, and wheat grown commercially in the north central US were analyzed. Chemical constituents of the varieties studied are presented to provide an overview of their characteristics. Lipids of the milled grain samples were solvent extracted, classified by silicic acid column chromatography, and separated by thin layer chromatography. Fatty acid composition of the total lipid was determined by gas liquid chromatography and the fatty acid content was determined by saponification and extraction. Total lipid content of the grains ranged from 2.3% for ‘Polk’ wheat to 6.6% for ‘Chief’ oats. Lipid composition varied considerably. The row crops, corn and sorghum, have a high neutral lipid and low glycolipid content. The small grain varieties have a more balanced distribution among neutral lipids, glycolipids, and phospholipids. Fatty acid composition of the total lipid was similar for all grains. Minor qualitative differences were noted among the lipid classes of the 7 cereals.
Perception of Political Candidates Based on Their Stand on Abortion and Taxes

This study investigated whether young voters would vote for and volunteer to work for the election campaign of a presidential candidate, given the candidate's background and positions on two major campaign issues. Findings indicate that, although voter-candidate agreement on a single issue may be enough for a voter to vote for a candidate, agreement on both issues may be necessary before a voter agrees to volunteer to work for the candidate's election campaign.
Benign metastasizing leiomyoma.

Benign metastasizing leiomyoma is a rare clinical entity that has been described in several previous reports. Although the exact pathophysiology of the disease is unknown, two predominant theories exist: (1) metastasis from ah existing leiomyoma (cornmonly seen with uterine leiomyoma) or (2) multicentric leiomyomatous growths rather than actual metastases. We present an interesting case in which several elements of the patient′s history complicated the differential diagnosis.
Intrinsic signatures for scanned documents forensics : Effect of font shape and size

Recently there has been a great deal of interest in using features intrinsic to a data-generating sensor for the purpose of source identification. Numerous methods have been proposed for different problems related to sensor forensics, such as source camera identification using sensor noise as intrinsic signatures, printer identification using banding artifacts as intrinsic signatures and so on. The goal of our work is to identify the scanner used for generating a scanned (digital) version of a printed (hard-copy) document. In this paper we do extensive analysis of the effect of font shape and size on our recently proposed, texture analysis based intrinsic signatures for scanned documents. Some improvements in these intrinsic signatures are proposed to make them robust to font shapes and sizes.
Mössbauer effect measurements in the first and second excited states of gadolinium-155☆

Abstract Mossbauer studies in 155Gd set a lower limit for lifetime of the first excited state of 0.22 nanoseconds. Observed quadrupole structure implies a spin of 1 2 for the second excited state and quadrupole splitting of 9.3 × 10−7 eV for the ground state.
Conflict and Compromise in Public Health Policy Analysis of Changes Made to Five Competitive Food Legislative Proposals Prior to Adoption

Competitive foods in schools have historically been scrutinized for their ubiquity and poor nutritional quality, leading many states to enact legislation limiting the availability and accessibility of these items. Evaluations of these policy approaches show their promise in improving the healthfulness of school food environments, considered an important strategy for reducing childhood obesity. Yet little is known about the decision-making processes by which such legislation is formed and adopted. Using a comparative case study design, this study describes and analyzes the policy formation processes surrounding five state-level competitive food bills introduced in 2009-2010. Data for each case were drawn from multiple key informant interviews and document reviews. Case studies were conducted, analyzed, and written independently using a standard protocol and were subsequently compared for recurring and unique themes. Abbreviated case studies and summary tables are provided. Results indicate that bill cost is a major barrier to achieving strong, health-promoting policy change. Additionally, findings reveal that supporters of stronger competitive food policies often concede to changes that weaken a bill in order to neutralize opposition and achieve stakeholder buy-in. These challenges suggest that continued research on the development, implementation, and evaluation of public health policies can contribute to the advancement of new strategies for effective health promotion.
Rejoinder to Macunovich

Virginia Deane Abernethy comments on Diane Macunovichs rejoinder wherein she confirms that each new immigrant to the US results in approximately one less birth to native-born Americans. Abernethys reactions focus on a footnote in Macunovichs rejoinder which states that her reanalysis excludes Blacks because of her assumption that Abernethys concerns are “primarily with the White/non-White distinction.” This footnote was suggestive of an attempt to tar as racist anyone who points out that continuing high levels of immigration make it impossible to stabilize population size in the US. In response Abernethy cites that the 1997 report on immigration by the National Research Council concluded that immigration is on track to account for almost all of future US population growth. Regarding the race issue it is noted that almost any newspaper reporting on immigration points out that Blacks are shortly to be replaced by Hispanics as the largest minority group in the US. Moreover Abernethy cites several evidences indicating that population stabilization and racial harmony are shrinking goals because of immigration.
Quasi-symmetric electrochromic device for light modulation.

A new quasi-symmetric electrochromic device is described for transmission modulation of a switchable window. The calculation technique to design such an electrochromic window for transmission (or reflection) modulation is applied to the (electrode/WO3/electrolyte/WOx/electrode) system. Advantages and limits of such a quasi-symmetrical system are also discussed.
Intracellular Spatial Localization Regulated by the Microtubule Network

The commonly recognized mechanisms for spatial regulation inside the cell are membrane-bounded compartmentalization and biochemical association with subcellular organelles. We use computational modeling to investigate another spatial regulation mechanism mediated by the microtubule network in the cell. Our results demonstrate that the mitotic spindle can impose strong sequestration and concentration effects on molecules with binding affinity for microtubules, especially dynein-directed cargoes. The model can recapitulate the essence of three experimental observations on distinct microtubule network morphologies: the sequestration of germ plasm components by the mitotic spindles in the Drosophila syncytial embryo, the asymmetric cell division initiated by the time delay in centrosome maturation in the Drosophila neuroblast, and the diffusional block between neighboring energids in the Drosophila syncytial embryo. Our model thus suggests that the cell cycle-dependent changes in the microtubule network are critical for achieving different spatial regulation effects. The microtubule network provides a spatially extensive docking platform for molecules and gives rise to a “structured cytoplasm”, in contrast to a free and fluid environment.
Investigation of Learning Outcomes for the Acquisition and Retention of CPR Knowledge and Skills Learned with the Use of High-Fidelity Simulation

Abstract Background There is currently no evidence of increased acquisition and retention of cardiopulmonary resuscitation (CPR) knowledge and skills learned with the use of human patient simulation (HPS) experiences for undergraduate nursing students. Method A quasi-experimental design was used to compare the acquisition and retention of CPR knowledge and skills for nursing students; the control group did not receive the simulation experience, and the experimental group did. Results The HPS cardiopulmonary arrest scenario had a statistically significant effect on the acquisition of both CPR knowledge and skills. The 3-month retention scores for the experimental group were also significantly higher than for the control group. Conclusions This information may assist health care educators to teach CPR with improved learning outcomes.
Evolution of communication in perfect and imperfect worlds

We extend previous work on cooperation to some related questions regarding the evolution of simple forms of communication. The evolution of cooperation within the iterated Prisoner's Dilemma has been shown to follow different patterns, with significantly different outcomes, depending on whether the features of the model are classically perfect or stochastically imperfect (Axelrod, 1980a,b, 1984, 1985; Axelrod and Hamilton, 1981; Nowak and Sigmund, 1990, 1992; Sigmund, 1993). Our results here show that the same holds for communication. Within a simple model, the evolution of communication seems to require a stochastically imperfect world.
Tribological behavior of DLC coatings with functionally gradient interfaces

Abstract Initial evidence showed that soft substrate materials (such as Ti–6Al–4V alloy) might not be able to provide adequate support for hard DLC films, adversely affecting their tribological performance and durability. An innovative concept in the development of advanced tribological systems involves coatings with a functionally-graded interface (FGI). This concept was experimentally studied in the present work by developing a model system involving DLC coatings with FGI based on theoretical finite element analysis (FEA) predictions. It was found that the durability of the DLC film is affected by the presence of the FGI and the loading level. Under low loading, FGI has a small effect due to the limited yielding occurring in the substrate. Under high loading conditions, the presence of FGI produced significant improvements (∼80% increase in coating lifetime). In view of the FEA predictions, these effects can be attributed to reduction of the plastic zone size and prevention of yielding at the coating/substrate interface.
Effects of team outcome on children's self-perception: little league baseball.

.— To determine how children use various attributional categories in making judgments about themselves as a function of team performance outcomes, answers were sought to the questions of how invariant children's perceptions of their characteristics are, and how they expect social agents to judge them under the various outcome conditions of team performance. Subjects were 300 Little League baseball players. Team failure did not decrease the players' judgments of their own internal qualities (ability and effort) but did decrease their judgments of those of the team. In addition, the players judged themselves and expected social agents (coach and spectators) to judge them as being unlucky and having a difficult task following team failure. Theoretical implications of the results were discussed.
Positioning photonic crystal cavities to single InAs quantum dots

We have investigated the optical properties of planar photonic crystal cavities formed by removing a single hole from a twodimensional square lattice of air holes etched through a thin GaAs slab. We have demonstrated cavity resonances with quality factors (Q’s) as high as 8500, using an internal light source provided by an ensemble of InAs quantum dots (QDs) grown by molecular beam epitaxy (MBE). The high-Q modes are confined to a very small mode volume, V = 0.7(l/n) 3 , making them attractive to study in the context of cavity quantum electrodynamics with single QDs, where a high Q= ffiffiffiffi V
Magnetic-Resonance-Based Electrical Properties Tomography: A Review

Frequency-dependent electrical properties (EPs; conductivity and permittivity) of biological tissues provide important diagnostic information (e.g., tumor characterization), and also play an important role in quantifying radiofrequency (RF) coil induced specific absorption rate (SAR), which is a major safety concern in high- and ultrahigh-field magnetic resonance imaging (MRI) applications. Cross-sectional imaging of EPs has been pursued for decades. Recently introduced electrical properties tomography (EPT) approaches utilize the measurable RF magnetic field induced by the RF coil in an MRI system to quantitatively reconstruct the EP distribution in vivo and noninvasively with a spatial resolution of a few millimeters or less. This paper reviews the EPT approach from its basic theory in electromagnetism to the state-of-the-art research outcomes. Emphasizing on the imaging reconstruction methods rather than experimentation techniques, we review the developed imaging algorithms, validation results in physical phantoms and biological tissues, as well as their applications in in vivo tumor detection and subject-specific SAR prediction. Challenges for future research are also discussed.
Temporal changes of cytochrome P450 (Cyp) and eicosanoid-related gene expression in the rat brain after traumatic brain injury

Traumatic brain injury (TBI) induces arachidonic acid (ArA) release from cell membranes. ArA metabolites form a class of over 50 bioactive eicosanoids that can induce both adaptive and/or maladaptive brain responses. The dynamic metabolism of ArA to eicosanoids, and how they affect the injured brain, is poorly understood due to their diverse activities, trace levels, and short half-lives. The eicosanoids produced in the brain postinjury depend upon the enzymes present locally at any given time. Eicosanoids are synthesized by heme-containing enzymes, including cyclooxygenases, lipoxygenases, and arachidonate monoxygenases. The latter comprise a subset of the cytochrome P450 “Cyp” gene family that metabolize fatty acids, steroids, as well as endogenous and exogenous toxicants. However, for many of these genes neither baseline neuroanatomical nor injury-related temporal expression have been studied in the brain. In a rat model of parietal cortex TBI, Cyp and eicosanoid-related mRNA levels were determined at 6 h, 24 h, 3d, and 7d postinjury in parietal cortex and hippocampus, where dynamic changes in eicosanoids have been observed. Quantitative real-time polymerase chain reaction with low density arrays were used to assay 62 rat Cyps, 37 of which metabolize ArA or other unsaturated fatty acids; 16 eicosanoid-related enzymes that metabolize ArA or its metabolites; 8 eicosanoid receptors; 5 other inflammatory- and recovery-related genes, plus 2 mouse Cyps as negative controls and 3 highly expressed “housekeeping” genes. Sixteen arachidonate monoxygenases, 17 eicosanoid-related genes, and 12 other Cyps were regulated in the brain postinjury (p < 0.05, Tukey HSD). Discrete tissue levels and distinct postinjury temporal patterns of gene expression were observed in hippocampus and parietal cortex. The results suggest complex regulation of ArA and other lipid metabolism after TBI. Due to the temporal nature of brain injury-induced Cyp gene induction, manipulation of each gene (or its products) at a given time after TBI will be required to assess their contributions to secondary injury and/or recovery. Moreover, a better understanding of brain region localization and cell type-specific expression may be necessary to deduce the role of these eicosanoid-related genes in the healthy and injured brain.
VMSTP Combined Degree Training (VMD/PhD): key features of the program at the University of Pennsylvania.

The Veterinary Medical Scientist Training Program (VMSTP), a combined degree program at the University of Pennsylvania School of Veterinary Medicine (Penn), has been in existence for approximately 35 years and has an excellent track record of producing veterinary physician-scientists. There are a number of key features of the program that I believe have been crucial to its success. Many of these features relate to how the PhD training component of the combined degree program is accomplished. Rather that describing the veterinary training component of the program, I will describe the PhD training component and how this training intersects with the veterinary curriculum. The key features of the VMSTP program at Penn are (1) admitting the right candidates, (2) placing the PhD training component of the program in the hands of individual graduate groups, (3) being committed to PhD training of veterinary students that is not compromised in terms of quality or time, (4) devising mechanisms to interdigitate VMD a...
Binding of diphosphoglycerate and ATP to oxyhemoglobin dimers.

Abstract The relative affinity of diphosphoglycerate and ATP for hemoglobin dimers and tetramers can be measured under conditions where the protein is in large molar excess over the polyphosphate. Binding of both compounds to dimers was about 25 times stronger than to tetramers in the case of the three low-spin hemoglobins, oxyhemoglobin, carboxyhemoglobin and cyanomethemoglobin. The mutation in hemoglobin Kansas leads to an increased dissociation into αβ dimers. The increase in diphosphoglycerate binding by this hemoglobin was in good agreement with that expected from the dimer-tetramer dissociation constant over a wide range of hemoglobin concentrations. In contrast to the liganded hemoglobins, both deoxyhemoglobin and aquomethemoglobin bind the two polyanions as tetramers.
Electronic and geometrical structure and magnetic ordering in passivated Mn12O12-acetate nanomagnets

Abstract We performed electronic structure calculations on several Mn 12 O 12 and Mn 12 O 12 (COOH) 16 (H 2 O) 4 clusters to investigate the magnetic ordering and the role of the ligands in stabilizing the D 2 structure of the MnO core. Without passivation, an antiferromagnetic tower is more stable than the free D 2 Mn 12 O 12 core, but the ligands stabilize the D 2 symmetry which leads to ferrimagnetic ordering and a net moment of 20 μ B . Local Mn moments are presented and the electronic states most responsible for formation of the spin tunneling barrier are identified.
Stochastic Modal Models of Slender Uncertain Curved Beams Preloaded Through Clamping

Abstract This paper addresses the stochastic modeling of the stiffness matrix of slender uncertain curved beams that are forced fit into a clamped–clamped fixture designed for straight beams. Because of the misfit with the clamps, the final shape of the clamped–clamped beams is not straight and they are subjected to an axial preload. Both of these features are uncertain given the uncertainty on the initial, undeformed shape of the beams and affect significantly the stiffness matrix associated with small motions around the clamped–clamped configuration. A modal model using linear modes of the straight clamped–clamped beam with a randomized stiffness matrix is employed to characterize the linear dynamic behavior of the uncertain beams. This stiffness matrix is modeled using a mixed nonparametric–parametric stochastic model in which the nonparametric (maximum entropy) component is used to model the uncertainty in final shape while the preload is explicitly, parametrically included in the stiffness matrix representation. Finally, a maximum likelihood framework is proposed for the identification of the parameters associated with the uncertainty level and the mean model, or part thereof, using either natural frequencies only or natural frequencies and mode shape information of the beams around their final clamped–clamped state. To validate these concepts, three simulated, computational experiments were conducted within Nastran to produce populations of natural frequencies and mode shapes of uncertain slender curved beams after clamping. The three experiments differed from each other by the nature of the clamping condition in the in-plane direction. One experiment assumed a no-slip condition (zero in-plane displacement), another a perfect slip (no in-plane force), while the third one invoked friction. The first two experiments gave distributions of frequencies with similar features while the latter one yielded a strong deterministic dependence of the frequencies on each other, a situation observed and explained recently and thus not considered further here. Then, the application of the stochastic modeling concepts to the no-slip simulated data was carried out and led to a good matching of the probability density functions of the natural frequencies and the modal components, even though this information was not used in the identification process. These results strongly suggest the applicability of the proposed stochastic model.
Single unit activity related to behavior motivated by food reward

Abstract In our earlier works we observed an inhibition of single unit activity recorded from the globus pallidus during specific goal oriented sequences of behavior. The present report describes two additional experiments performed to obtain additional information concerning pallidal inhibitory responses. In Experiment I, squirrel monkeys were trained to press a lever and obtain food rewards or the pellets were automatically delivered following a 4 sec tone. Experiment II employed a 3:1 fixed ratio schedule of reinforcement to determine the extent to which pallidal inhibitory patterns were related to lever responses and post-lever response events involved in the acquisition of food reinforcement. Thirty-one of 97 pallidal units recorded in the combined experiments exhibited pronounced and immediate reductions in spike discharge rates during either food-searching movements in the hopper, food grasping and transporting movements or during actual consummatory behavior. These same pallidal units were not responsive to elicited or spontaneous motor patterns involved in obtaining objects other than food. We suggest that the initiation of the inhibitory phenomenon is conditional upon the convergence of several sensory imputs and the pallidal units provide messages which release or direct other motor systems to carry out such goal-related activities as seeking, grasping and masticating food objects.
Educational attainment and longevity: results from the REGARDS U.S. national cohort study of blacks and whites.

Background Educational attainment may be an important determinant of life expectancy. However, few studies have prospectively evaluated the relationship between educational attainment and life expectancy using adjustments for other social, behavioral, and biological factors.
Effect of secretor status on vaginal and rectal colonization with fimbriated escherichia coli in women with and without recurrent urinary tract infection

The prevalence and duration of rectal and vaginal colonization with P- and F-fimbriated Escherichia coli and the relationship of colonization with these strains to blood group secretor status was investigated. Rectal and vaginal E. coli isolates were prospectively collected twice monthly for 6 months from 20 young women with and 20 without a history of recurrent urinary tract infection (UTI). Rectal and vaginal colonization with P- and/or F-fimbriated E. coli was highly prevalent. Nonsecretors who developed UTI during the study period were significantly more likely to be colonized rectally with F-fimbriated E. coli than were the infected secretors (56% vs. 27%; P = .042) or uninfected nonsecretors (56% vs. 31%; P = .046). Persistent vaginal and rectal E. coli colonization with fimbriated organisms occurred commonly in the study patients but was not often temporally associated with the development of UTI. Results suggest that nonsecretors are more susceptible than secretors to colonization with F adhesin-bearing E. coli isolates.
Progressive auction based resource allocation in service-oriented architecture

The emerging paradigm of distributed Web services has promised seamless business integration across the Internet that shares not only computing power but also applications. One major challenge is resource allocation to each end user in an economically efficient and low latency manner. A common solution is proportional sharing where each user gets his resource in proportion to the predetermined weight. However, this does not allow users to differentiate the value of their services and to dynamically adjust the weights. A resource reservation mechanism may improve the information and service sharing but usually introduces a high latency. In this paper, we propose a progressive auction based market mechanism for resource allocation that allows user differentiation of the service value and ensures the resource acquisition latency to be limited only to the communication delay in service-oriented architecture (SOA) systems. We present a service sharing prototype for selecting services for further business process composition or solution creation and show experimental results on the formation of reliable user ranking in resource sharing through the progressive auction.
Using Software Stacks to Explain Complementarities: The Case of Mergers and Acquisitions in the Software Industry

The existence of product complementarities is especially relevant in network-type industries, such as information technology and communications, where systems of complementary components made by different manufacturers have to be assembled. Relying on the characteristics of software markets, this paper investigates how complementarity creates value in M&As between software companies. We empirically validate the software "stack". In a sample of Mergers and Acquisitions, in which either the acquirer or the target is a software firm, we find an inverse curvilinear relationship between abnormal returns and the distance between acquirers and targets in various layers of the stack.
Assessing the spatial implications of interactions among strategic forest management options using a Windows-based harvest simulator

Forest management planners must develop strategies to produce timber in ways that do not compromise ecological integrity or sustainability. These strategies often involve modifications to the spatial and temporal scheduling of harvest activities, and these strategies may interact in unexpected ways. We used a timber harvest simulator (HARVEST 6.0) to determine the sensitivity of landscape pattern to the interactions among three strategic parameters: adjacency constraints, spatial dispersion, and size of harvest units. Adjacency constraints reduced the ability of HARVEST to meet cutting targets by up to 70%, depending on other parameters used, while spatial dispersion had a minimal effect. Adjacency constraints had little effect on patch size except when harvests were clustered. Adjacency constraints increased variability in the amount of forest interior and edge, but had a marginal effect on the total amount. Mean patch size decreased even though the mean size of new patches was greater than the initial mean size, because many small remnant patches were created when harvests did not completely fill some existing stands. A clustered spatial dispersion increased the amount of forest interior habitat. Our description of the intuitive interface of HARVEST 6.0 also shows that HARVEST has advanced from being strictly a research tool to a strategic management planning tool. Published by Elsevier Science B.V.
Guiding of electromagnetic waves by uniformly rough surfaces: Part II

A simple derivation is given for the reflection of electromagnetic waves from a perfectly-conducting plane surface which has a uniform distribution of hemispherical bosses whose electrical constants are arbitrary. The spacing between the centers of the bosses is taken to be small, which is the justification for neglecting the incoherent radiation. An approximate boundary condition is developed which must be satisfied in an average sense by the tangential fields on the reference plane. The excitation of surface waves on the rough surface is then discussed. It is indicated that to a first order, a rough surface of the kind described here possesses an inductive surface reactance and will support a trapped wave. The effect of finite conductivity of the bosses is to damp exponentially this trapped wave.
Do Persistent Large Cash Reserves Hinder Performance

Conservative financial policies are often criticized as serving the interests of managers rather than the interests of stockholders. We test this argument by examining the operating performance and other characteristics of firms that for a five-year period held more than one-fourth of their assets in cash and cash equivalents. Following the five-year period, operating performance of high cash firms is comparable to or greater than the performance of firms matched by size and industry or by a measure of proclivity to hold substantial cash. In addition, proxies for managerial incentive problems, such as ownership and board characteristics, are not unusual and do not explain differences in operating performance among high cash firms. We find that high cash holdings are accompanied by greater investment, particularly R&D expenditures, and by greater growth in assets. For firms that persistently hold large cash reserves, we conclude that such policies support investment without hindering corporate performance.
Sinoatrial-Node Entrance Block

Sinus-node function was characterized in 13 patients during cardiac catheterization by the introduction of progressively premature atrial depolarizations. Curves relating the extent of sinus-node depression following these premature depolarizations and their degree of prematurity were constructed. The maximum extent of sinus-node depression following premature depolarizations and A-V-nodal and atrial refractoriness were determined. Maximum sinus-node depression could be demonstrated to be independent of sinus rate. In six patients "early" atrial premature depolarizations demonstrated entrance block into the sinus-node pacemaker. Sinoatrial (SA) node entrance block could be clearly distinguished from atrial echoes and repetitive atrial firing subsequent to stimulation during the atrial relative refractory period. Prolonged refractoriness of tissues conducting impulses between atrium and sinus node was unrelated to parameters of sinus-node automaticity (sinus rate or maximum depression following premature a...
Isomaltooligosaccharide increases cecal Bifidobacterium population in young broiler chickens

A newly developed compound derived by fermentation, isomaltooligosaccharide (IMO), was hypothesized to enrich cecal bifidobacterial populations and reduce colonization levels of Salmonella in the ceca of broiler chickens. Broiler starter diets were prepared with final IMO concentrations of 1% (wt/wt), 2% (wt/wt), and 4% (wt/wt) and a control diet without IMO supplementation. Chickens were divided into 4 groups and challenged with 10(8) cell of Salmonlella enterica ser. Typhimurium with 200 microg/mL nalidixic acid resistant (S. Typhimurium Nalr) after 7 d of placement. The experiment was done in 3 replications. IMO-supplemented diets resulted in significantly higher cecal bifidobacteria compared with the control diet (P < 0.05). However, there was no significant difference in bifidobacteria counts among the treatment groups. Chickens fed diets with 1% IMO had a significant 2-log reduction in the level of inoculated S. Typhimurium Nalr (P < 0.05) present in, the ceca compared with the control group, but no differences were found between the control group and the groups fed 2 or 4% IMO for S. Typhimurium Nalr. No differences in feed consumption, feed conversion, or feed efficiency compared with the control group were observed; however, the result showed a significant reduction in weight for birds fed 1% IMO diet compared with those fed the control diet.
Protein Phosphatases Pph3, Ptc2, and Ptc3 Play Redundant Roles in DNA Double-Strand Break Repair by Homologous Recombination

In response to a DNA double-strand break (DSB), cells undergo a transient cell cycle arrest prior to mitosis until the break is repaired. In budding yeast (Saccharomyces cerevisiae), the DNA damage checkpoint is regulated by a signaling cascade of protein kinases, including Mec1 and Rad53. When DSB repair is complete, cells resume cell cycle progression (a process called “recovery”) by turning off the checkpoint. Recovery involves two members of the protein phosphatase 2C (PP2C) family, Ptc2 and Ptc3, as well as the protein phosphatase 4 (PP4) enzyme, Pph3. Here, we demonstrate a new function of these three phosphatases in DSB repair. Cells lacking all three phosphatases Pph3, Ptc2, and Ptc3 exhibit synergistic sensitivities to the DNA-damaging agents camptothecin and methyl methanesulfonate, as well as hydroxyurea but not to UV light. Moreover, the simultaneous absence of Pph3, Ptc2, and Ptc3 results in defects in completing DSB repair, whereas neither single nor double deletion of the phosphatases causes a repair defect. Specifically, cells lacking all three phosphatases are defective in the repair-mediated DNA synthesis. Interestingly, the repair defect caused by the triple deletion of Pph3, Ptc2, and Ptc3 is most prominent when a DSB is slowly repaired and the DNA damage checkpoint is fully activated.
Network formation in the presence of contagious risk

There are a number of domains where agents must collectively form a network in the face of the following trade-off: each agent receives benefits from the direct links it forms to others, but these links expose it to the risk of being hit by a cascading failure that might spread over multistep paths. Financial contagion, epidemic disease, the exposure of covert organizations to discovery, and electrical power networks are all settings in which such issues have been articulated.Here we formulate the problem in terms of strategic network formation, and provide asymptotically tight bounds on the welfare of both optimal and stable networks. We find that socially optimal networks are, in a precise sense, situated just beyond a phase transition in the behavior of the cascading failures, and that stable graphs lie slightly further beyond this phase transition, at a point where most of the available welfare has been lost. Our analysis enables us to explore such issues as the trade-offs between clustered and anonymous market structures, and it exposes a fundamental sense in which very small amounts of “over-linking” in networks with contagious risk can have strong consequences for the welfare of the participants.
Automated Collection and Analysis of Malware Disseminated via Online Advertising

Online advertising system has become a convenient and efficient channel to disseminate Web-based malware to the Internet users. Most of the free online services exist in exchange of the revenues generated through advertisements. Therefore, considerable efforts are made to deliver the ads to the appropriate audiences. Cyber criminals can easily exploit this online ad delivery system to deliver malware to a very large number of end-users and their vulnerable machines. We observe that this active approach by cyber criminals can be exploited to expedite the collection of malware. In this paper, we propose an automated system that mimics high-risk browsing activities such as clicking on suspicious online ads, and as a result collects malicious executable files for further analysis and diagnosis. Using our system we crawled over the Internet for a period of 7 days to collect a significant amount of ad frame URLs, which has been monitored for another period of 7 days to collect more than 800 malicious executables. The experimental results showed that our system is quite effective in collecting online malware samples using very limited resources compared to other malware collecting honeypot systems.
Cost comparison of Transcatheter and Operative Pulmonary Valve Replacement (from the Pediatric Health Information Systems Database)

Outcomes for transcatheter pulmonary valve replacement (TC-PVR) and operative pulmonary valve replacement (S-PVR) are excellent. Thus, their respective cost is a relevant clinical outcome. We performed a retrospective cohort study of children and adults who underwent PVR at age ≥ 8 years from January 1, 2011, to December 31, 2013, at 35 centers contributing data to the Pediatric Health Information Systems database to address this question. A propensity score-adjusted multivariable analysis was performed to adjust for known confounders. Secondary analyses of department-level charges, risk of re-admission, and associated costs were performed. A total of 2,108 PVR procedures were performed in 2,096 subjects (14% transcatheter and 86% operative). The observed cost of S-PVR and TC-PVR was not significantly different (2013US $50,030 vs 2013US $51,297; p = 0.85). In multivariate analysis, total costs of S-PVR and TC-PVR were not significantly different (p = 0.52). Length of stay was shorter after TC-PVR (p <0.0001). Clinical and supply charges were greater for TC-PVR (p <0.0001), whereas laboratory, pharmacy, and other charges (all p <0.0001) were greater for S-PVR. Risks of both 7- and 30-day readmission were not significantly different. In conclusion, short-term costs of TC-PVR and S-PVR are not significantly different after adjustment.
Effects of desipramine hydrochloride on peripheral sympathetic nerve activity

Tricyclic antidepressants cause orthostatic hypotension and have antiarrhythmic effects that may be partially due to effects on the sympathetic nervous system. We studied the influence of intravenous desipramine hydrochloride on renal (n = 12) and lumbar (n = 5) nerve traffic and mean arterial pressure in alpha-chloralose-anesthetized rabbits with sinoaortic and vagal denervation. Desipramine administration resulted in dose-dependent inhibition of renal and lumbar nerve activity that was markedly reduced or abolished by yohimbine (0.5 mg/kg iv), an alpha 2-blocker that enters the brain rapidly. In contrast, administration of phentolamine (0.75 mg/kg iv), an alpha 1- and alpha 2-blocker with limited access to the brain, failed to alter the responses to desipramine. Because renal nerves are postganglionic and lumbar nerves are preganglionic, desipramine does not act via a ganglionic mechanism. Our results are best explained by an effect of desipramine on the sympathetic nervous system mediated via central alpha 2-receptors. This sympathoinhibitory effect of desipramine may contribute to its postural hypotensive effect and to its efficacy as an antiarrhythmic agent.
Identification of a 5-hydroxytryptamine (5-HT2) receptor on guinea pig small intestinal crypt cells

Radioligand labeling of [3H]ketanserin was examined in suspensions of dispersed guinea pig small intestinal mucosal cells prepared by modification of the EDTA-chelation method described by M. M. Weiser (J. Biol. Chem. 248: 2536-2541, 1973). Preferential incorporation of [3H]thymidine was used to confirm that suspensions were enriched in crypt cells. At 25 degrees C, binding of [3H]ketanserin to dispersed enterocytes was rapid, maximal by 5 min, saturable (dissociation constant = 1.5 nM), 65 +/- 5% specific, stable, and reversible. The maximal number of binding sites per cell was 92,000 (range 86,000-105,500). Binding was temperature dependent, with maximal binding at 37 degrees C, and was inhibited by 5-hydroxytryptamine (5-HT) (half-maximal inhibition of [3H]ketanserin binding observed in response to 1 microM 5-HT) and ketanserin (half-maximal inhibition of [3H]ketanserin binding observed in response to 1 nM ketanserin) but not by the 5-HT1P antagonist N-acetyl-5-hydroxytryptophyl 5-hydroxytryptophan amide (5-HTP-DP) or the 5-HT3 antagonist 3-tropanyl-indole-3-carboxylate methiodide (ICS-205-930). The second messenger system coupled to the putative mucosal 5-HT2 receptor was examined. 5-HT stimulated a concentration-dependent production of inositol 1,4,5-trisphosphate (IP3) in the dispersed enterocytes. This was maximal at 1 min and was inhibited in a concentration-dependent manner by ketanserin. 5-HTP-DP and ICS-205-930 had no effect on 5-HT-stimulated production of IP3. These data provide evidence for the existence of a mucosal 5-HT2 receptor located on guinea pig small intestinal crypt cells.
Simple Extensions of Topologies

(1964). Simple Extensions of Topologies. The American Mathematical Monthly: Vol. 71, No. 1, pp. 22-25.
Legal Ethics for the Millennials: Avoiding the Compromise of Integrity

Although young attorneys face many of the same ethical challenges faced by their older colleagues, they often lack the practice experience, maturity and training to fully appreciate many ethical dilemmas. An increasing number of attorneys are violating rules of professionalism in a variety of ways, and it is critical that younger attorneys are provided with sufficient training to better understand ethical issues that arise in today's complex society. The responsibility for ensuring that future lawyers have a firm legal ethics grounding falls to the law school, the state bar and law firms. In the Introduction, the author considers and discusses the need to provide additional training in ethics and professionalism, and argues that the current generation of law students are not receiving sufficient training under the current approach used in most law schools. She proposes that the legal community should attempt to understand the unique perspectives of today's law students, learn why they engage in unethical behaviors, provide sufficient education on the implications of such behavior in law practice, and only then hold them accountable for their misdeeds.Section II briefly addresses key distinctions between members of the Millennial generation and members of other generations that are relevant to the practice of law which dictates that generational differences warrant greater emphasis on ethics training for law students. Section III considers current practices related to ethics training at U.S law schools and argues that the existing training does not adequately prepare law students to handle the myriad of ethical challenges students typically encounter in the legal profession. Section IV offers recommendations for change.