cssi/SciSciGPT-SciSciNet huggingface dataset:
Revisiting erosion rate estimates from luminescence profiles in exposed bedrock surfaces using stochastic erosion simulations

Abstract Exposed bedrock is ubiquitous on terrestrial and planetary landscapes, yet little is known about the rate of granular-scale bedrock erosion on timescales longer than the instrumental record. As recently suggested, using the bleaching depth of luminescence signals as a measure of bedrock erosion may fit these scales. Yet this approach assumes constant erosion through time, a condition likely violated by the stochastic nature of erosional events. Here we simulate bedrock luminescence bleaching in response to power-law distributions of removal lengths and hiatus durations. We compare simulation results with previously measured luminescence profiles from boulder surfaces ( Sohbati et al., 2018 ) to illustrate that prolonged hiatuses are unlikely and that typical erosion scales are sub-granular with occasional loss at mm scales, consistent with ideas about microflaws governing bedrock detachment. For a wide range of erosion rates, measurements are integrated over many removal events, producing reasonably accurate estimates despite the stochastic nature of the simulated process. We hypothesize that the greater or equal erosion rates atop large boulders compared to rates at ground level suggest that subcritical cracking may be more influential than aeolian abrasion for boulder degradation in the Eastern Pamirs, China.
Status and summary of laser energy conversion

This paper presents a survey of the status of laser energy converters. Since the inception of these devices in the early 1970's, significant advances have been made in understanding the basic conversion processes. Numerous theoretical and experimental studies have indicated that laser energy can be converted at wavelengths from the ultraviolet to the far-infrared. These converters can be classified into five general categories: photovoltaics, heat engines, thermoelectronic, optical diode, and photochemical. The conversion can be directly into electricity (such as the photovoltaic, thermoelectronic, and optical diode) or it can go through an intermediate stage of conversion to mechanical energy, as in the heat engines. The photochemical converters result in storable energy such as hydrogen. Projected conversion efficiencies range from about 30% for the photochemical to nearly 75% for the heat engines.
Racial disparities in utilization and effectiveness of first-line therapies in metastatic castrate-resistant prostate cancer.

e17541Background: Prospective evidence suggests that abiraterone use is associated with improved progression-free survival in African-American (AA) men with metastatic castrate-resistant prostate c...
Laryngeal granular cell tumors in children: A literature review.

Abstract Objective Granular cell tumors of the larynx are exceedingly rare in the pediatric population. The purpose of this review is to further characterize features of these tumors and trends in their management. Methods A search of the PubMed, Ovid Medline and Cochrane Collaboration databases was undertaken using the terms: pediatric, child, laryngeal, larynx, granular cell tumor, granular cell myoblastoma, benign mass. Results A total of 38 children with laryngeal granular cell tumor were identified. Their ages ranged from 4 to 16 years. The most common presenting symptom was dysphonia. Five patients were previously treated for asthma. Within the laryngeal subsites, 49% presented with subglottic tumors, while 43% were found at the level of the glottis. Subglottic tumors were found anteriorly 42% of the time and posteriorly 53% of the time. Multifocal disease was present in four patients. Around half of patients were treated by cold steel excision and/or CO2 laser, 31% through laryngofissure, and two required laryngectomy. There were four documented cases of recurrence ranging from 4 months to 3 years after treatment. Conclusions Laryngeal granular cell tumor during childhood occurs most commonly in the subglottis. Posterior laryngeal tumors were more frequent than anterior tumors. Patients should be carefully evaluated for multifocal disease. Long-term surveillance for recurrence is recommended.
Diabetes mellitus—Infections and fracture healing

Abstract Care for the lower extremity in a patient with diabetes is a challenging but important facet of care both for the patient and the clinician. Diabetic foot ulcerations are a devastating condition that carry risks including infection, hospitalization, and loss of limb. Patients with diabetes are also at higher risk for fracture and fracture complication such as delayed and non-union. It is important that patients with diabetes are routinely screened for risk factors including peripheral neuropathy, peripheral arterial disease, and glycemic control in order to optimize management and improve outcomes. Management of this patient population requires a multi-disciplinary team approach along with dedication from the patient.
Terrorism, counterterrorism and ‘the rule of law’: state repression and ‘shoot-to-kill’ in Northern Ireland

Authors have argued that counterterrorism must be consistent with ‘the rule of law.’ Often associated with this approach is the assumption that plural political structures limit the state’s respons...
Autonomous Conceptions of Our Planetary Situation

This article is constructed through a series of linked aphorisms that articulate the relations between autonomy, sense, the world, different people’s worlds, disagreement, and wonder. It advances anthroponomy—the organization of humankind to support autonomous life. In the context of the planetary, sociallycaused environmental changes of today such as global warming or the risk of a mass extinction cascade, a part of autonomous engagement with our planetary situation is developing an autonomous conception of it—a conception of our situation that makes sense to us. This pluralistic idea has consequences for environmentalism, notably around coloniality, and the reduction of different autonomous worlds to a dominant world, which is currently part of the discourse of the Anthropocene. The aphorisms in this article develop a reflective path toward autonomous conceptions of our planetary situation given the reality of coloniality in how that situation is understood. One result of this path is to open up a way for people to become more autonomously engaged with our environmental situation, an engagement grounded in wonder and critical of the discourse of the “Anthropocene”.
Electric Field Strength From Prefrontal Transcranial Direct Current Stimulation Determines Degree of Working Memory Response: A Potential Application of Reverse-Calculation Modeling?

Background Transcranial direct current stimulation (tDCS) for working memory is an enticing treatment, but there is mixed evidence to date. Objectives We tested the effects of electric field strength from uniform 2 mA dosing on working memory change from prestimulation to poststimulation. Second, we statistically evaluated a reverse-calculation method of individualizing tDCS dose and its effect on normalizing electric field at the cortex. Materials and methods We performed electric field modeling on a dataset of 28 healthy older adults (15 women, mean age = 73.7, SD = 7.3) who received ten sessions of active 2 mA tDCS (N = 14) or sham tDCS (N = 14) applied over bilateral dorsolateral prefrontal cortices (DLPFC) in a triple-blind design. We evaluated the relationship between electric field strength and working memory change on an N-back task in conditions of above-median, high electric field from active 2 mA (N = 7), below-median, low electric field from active 2 mA (N = 7), and sham (N = 14) at regions of interest (ROI) at the left and right DLPFC. We then determined the individualized reverse-calculation dose to produce the group average electric field and measured the electric field variance between uniform 2 mA doses vs. individualized reverse-calculation doses at the same ROIs. Results Working memory improvements from pre- to post-tDCS were significant for the above-median electric field from active 2 mA condition at the left DLPFC (mixed ANOVA, p = 0.013). Furthermore, reverse-calculation modeling significantly reduced electric field variance at both ROIs (Levene's test; p Conclusions Higher electric fields at the left DLPFC from uniform 2 mA doses appear to drive working memory improvements from tDCS. Individualized doses from reverse-calculation modeling significantly reduce electric field variance at the cortex. Taken together, using reverse-calculation modeling to produce the same, high electric fields at the cortex across participants may produce more effective future tDCS treatments for working memory.
Differential cytotoxicity, ER/oxidative stress, dysregulated AMPKα signaling, and mitochondrial stress by ethanol and its metabolites in human pancreatic acinar cells.

Background Alcoholic chronic pancreatitis (ACP) is a serious inflammatory disorder of the exocrine pancreatic gland. A previous study from this laboratory showed that ethanol (EtOH) causes cytotoxicity, dysregulates AMPKα and ER/oxidative stress signaling, and induces inflammatory responses in primary human pancreatic acinar cells (hPACs). Here we examined the differential cytotoxicity of EtOH and its oxidative (acetaldehyde) and nonoxidative (fatty acid ethyl esters; FAEEs) metabolites in hPACs was examined to understand the metabolic basis and mechanism of ACP. Methods We evaluated concentration-dependent cytotoxicity, AMPKα inactivation, ER/oxidative stress, and inflammatory responses in hPACs by incubating them for 6 h with EtOH, acetaldehyde, or FAEEs at clinically relevant concentrations reported in alcoholic subjects using conventional methods. Cellular bioenergetics (mitochondrial stress and a real-time ATP production rate) were determined using Seahorse XFp Extracellular Flux Analyzer in AR42J cells treated with acetaldehyde or FAEEs. Results We observed concentration-dependent increases in LDH release, inactivation of AMPKα along with upregulation of ACC1 and FAS (key lipogenic proteins), downregulation of p-LKB1 (an oxidative stress-sensitive upstream kinase regulating AMPKα) and CPT1A (involved in β-oxidation of fatty acids) in hPACs treated with EtOH, acetaldehyde, or FAEEs. Concentration-dependent increases in oxidative stress and ER stress as measured by GRP78, unspliced XBP1, p-eIF2α, and CHOP along with activation of p-JNK1/2, p-ERK1/2, and p-P38MAPK were present in cells treated with EtOH, acetaldehyde, or FAEEs, respectively. Furthermore, a significant decrease was observed in the total ATP production rate with subsequent mitochondrial stress in AR42J cells treated with acetaldehyde and FAEEs. Conclusions EtOH and its metabolites, acetaldehyde and FAEEs, caused cytotoxicity, ER/oxidative and mitochondrial stress, and dysregulated AMPKα signaling, suggesting a key role of EtOH metabolism in the etiopathogenesis of ACP. Because oxidative EtOH metabolism is negligible in the exocrine pancreas, the pathogenesis of ACP could be attributable to the formation of FAEEs and related pancreatic acinar cell injury.
Non-invasive MRI Derived Hemodynamic Simulation to Predict Successful vs. Unsuccessful Catheter Interventions for Branch Pulmonary Artery Stenosis: Proof-of-Concept and Experimental Validation in Swine

This study assessed the ability of hemodynamic simulations to predict the success of catheter interventions in a swine model of branch pulmonary artery stenosis (bPAS). bPAS commonly occurs in congenital heart disease and is often managed with catheter based interventions. However, despite technical success, bPAS interventions do not lead to improved distal pulmonary blood flow (PBF) distribution in approximately 1/3rd of patients. New tools are needed to better identify which patients with bPAS would most benefit from catheter interventions. For 13 catheter intervention cases in swine with surgically created left PAS (LPAS), PA pressures from right heart catheterization (RHC) and PBF distributions from MRI were measured before and after catheter interventions. Hemodynamic simulations with a reduced order computational fluid dynamics (CFD) model were performed using non-invasive PBF measurements derived from MRI, and then correlated with changes in invasive measures of hemodynamics and PBF distributions before and after catheter intervention to relieve bPAS. Compared to experimentally measured changes in left PBF distribution, simulations had a small bias (3.4 ± 11.1%), moderate agreement (ICC = 0.69 [0.24–0.90], 0.71 [0.23–0.91]), and good diagnostic capability to predict successful interventions (> 20% PBF increase) (AUC 0.83 [0.59–1.0]). Simulations had poorer prediction of changes in stenotic pressure gradient (ICC = 0.28 [− 0.33 to 0.73], r = 0.57 [− 0.04 to 0.87]) and MPA systolic pressure (ICC = 0.00 [− 0.52 to 0.53], r = 0.29 [− 0.32 to 0.72]). While there was only weak to moderate agreement between predicted and measured changes in PA pressures and pulmonary blood flow distributions, hemodynamic simulations did show good diagnostic value for predicting successful versus unsuccessful catheter based interventions to relieve bPAS. The results of this proof of concept study are promising and should encourage future development for using hemodynamic models in planning interventions for patients with bPAS.
StudentsA Heterogeneous Preferences and the Uneven Spatial Distribution of Colleges

We estimate a model of high school students' college choices, allowing for rich heterogeneity in students' preferences for college attributes. We use data on students' enrollment decisions and application decisions—i.e., the sets of colleges to which they applied—to identify the distribution of students' preferences. We use our estimates to quantify differences in a student's expected value upon college application that result from the uneven spatial distribution of colleges. As with other aspects of economic opportunity, we find that place matters: students with otherwise identical characteristics can have very different expected values depending on where they live. The importance of location reflects differences across states as well as differences across counties within a state. For students with low parental incomes and low SAT scores, over 70% of the variation is within-state across counties, while for students with high parental incomes and high SAT scores, 66% of the variation is across states. Institutional subscribers to the NBER working paper series, and residents of developing countries may download this paper without additional charge at www.nber.org.
Transit-induced gentrification and displacement: The state of the debate

Abstract Investments in new transportation infrastructure hold the potential to transform the urban socioeconomic landscape by reshaping accessibility and by encouraging new developments around these investments. This chapter outlines the theoretical arguments for why and how transport, specifically rail transit, is expected to impact the socioeconomic composition of neighborhoods and reviews the relevant empirical literature on the subject. Neighborhood socioeconomic change, including gentrification, can be viewed as the product of shifts in residential sorting of residents reacting to the placement of a new (transit) amenity which may place increased demand for living in a particular area. This demand may place an upward pressure on nearby housing values and rents, affecting the socioeconomic composition of those willing and able to afford these price premiums, thus spurring or accelerating gentrification. Rising land values may also lead to the disproportionate exit of lower-income residents unable to keep up with elevated rents or property taxes. To date, the empirical evidence on the link between transport investments and gentrification has mixed findings, very often underscoring the importance of local context in directing a neighborhood's path. Research has overwhelmingly centered on aggregate neighborhood changes, but several studies have recently emerged that center on individual movements that give rise to these neighborhood-scale outcomes.
How to do things with nonwords: pragmatics, biosemantics, and origins of language in animal communication

Recent discussions of animal communication and the evolution of language have advocated adopting a ‘pragmatics-first’ approach, according to which “a more productive framework” for primate communication research should be “pragmatics, the field of linguistics that examines the role of context in shaping the meaning of linguistic utterances” (Wheeler and Fischer, Evol Anthropol 21:195–205, 2012: 203). After distinguishing two different conceptions of pragmatics that advocates of the pragmatics-first approach have implicitly relied on (one Carnapian, the other Gricean), I argue that neither conception adequately serves the purposes of pragmatics-first approaches to the origins of human linguistic communication. My main aim in this paper is to motivate–and begin to articulate–an intermediary conception whose scope is narrower than Carnapian pragmatics but broader than Gricean pragmatics. To do so, I first spell out what I take to be the key insight offered by proponents of the Gricean approach concerning the emergence of linguistic communication, namely, its being communication ‘from a psychological point of view’ (Tomasello, Origins of human communication, MIT Press, Cambridge MA, 2008). I then develop this insight using key elements from the anti-Gricean ‘biosemantic’ account of linguistic communication due to Ruth Millikan (Millikan, Language, thought, and other biological categories: New foundations for realism, MIT Press, Cambridge MA, 1984, Millikan, Tomberlin (ed), Philosophical Perspectives 9, Ridgeview Publishing, Atascedero CA, 1995, Millikan R (2006) Varieties of Meaning. Mass.: The MIT Press (paperback edition), Cambridge, Millikan, Beyond concepts: unicepts, language, and natural information, Oxford University Press, Oxford UK, 2017, and elsewhere). I argue that the intermediary pragmatics-first approach that I propose, which draws on both Gricean and Millikanian resources, would be better equipped to serve the purposes of those who search for potential precursors of human linguistic communication in animal communication.
Intermittent gallstone ileus of six years' duration.

Summary A case of intermittent gallstone ileus of at least six years' duration is presented. Prior cholecystectomy, absence of roentgen findings of biliary fistula, and the unusually long duration of the complaint complicated the diagnosis.
Quantifying regional scale ecosystem response to changes in precipitation: Not all rain is created equal

[1] Primary productivity and vegetation cover are strongly related to how precipitation is partitioned into surface discharge, storage, and evapotranspiration (ET). Thus, quantifying feedbacks between changes in precipitation and vegetation at regional scales is a critical step toward predicting both carbon balance and water resources as climate and land cover change. We used a catchment-based approach to quantify partitioning of precipitation and compared these hydrologic fluxes to remotely sensed vegetation greenness (NDVI) in 86 U.S. catchments between 2000 and 2008. The fraction of precipitation potentially available to vegetation (catchment wetting; W) ranged from 0.64 to 0.99 demonstrating that up to 36% of precipitation was not available to vegetation. The ratio of ET:W (Horton Index (HI)), ranged from 0.07 to 1.0 demonstrating even greater variability in the fraction of catchment wetting used as ET. Negative slopes between annual Horton Index and maximum annual NDVI values indicated water limitation during dry years in most catchment ecosystems. Not surprisingly, grasslands were more sensitive to drying than forests. However, in nine of the wettest (HI < 0.66) catchment ecosystems, NDVI values increased as HI increased suggesting greater vegetation productivity under drier conditions. Our results demonstrate that catchment-scale hydrologic partitioning provides information on both the fractions of precipitation available to and used by vegetation. Their ratio (HI) identifies shifts between water and energy limitation, and differential sensitivity to drying based on vegetation type within catchment ecosystems. Consequently, catchment-scale partitioning provides useful information for scaling point observations and quantifying regional ecohydrological response to climate or vegetation change.
Managing the Supplier-Supplier Interface in Product Development: The Moderating Role of Technological Newness

When developing products such as computers, machinery and automobiles, interdependent components developed by different first-tier suppliers must fit together and perform as expected in the final product. Applying information processing theory and social network theory, this research explores three approaches that buyers can use to manage the interface between interdependent first-tier suppliers during product development. These are (1) using an interactive team, (2) making a supplier–supplier connection by encouraging first-tier suppliers to communicate, coordinate and mutually adjust and (3) using a modular design. Data were gathered in an online survey of buying firms in manufacturing industries and hypotheses were tested using hierarchical moderated regression. Results show that interactive teams increase the quality of the component system and that modular designs increase product development efficiency. Interactive teams are more beneficial for system quality when the technology used for components are new to suppliers.
Defeasibility in answer set programs via argumentation theories

Defeasible reasoning has been studied extensively in the last two decades and many different and dissimilar approaches are currently on the table. This multitude of ideas has made the field hard to navigate and the different techniques hard to compare. Our earlier work on Logic Programming with Defaults and Argumentation Theories (LPDA) introduced a degree of unification into the approaches that rely on the well-founded semantics. The present work takes this idea further and introduces ASPDA--a unifying framework for defeasibility of disjunctive logic programs under the Answer Set Programming (ASP). Since the well-founded and the answer set semantics underlie almost all existing approaches to defeasible reasoning in Logic Programming, LPDA and ASPDA together capture most of those approaches. In addition to ASPDA, we obtained a number of interesting and non-trivial results. First, we show that ASPDA is reducible to ordinary ASP programs, albeit at the cost of exponential blowup in the number of rules. Second, we study reducibility of ASPDA to the non-disjunctive case and show that head-cycle-free ASPDA programs reduce to the non-disjunctive case-- similarly to head-cycle-free ASP programs, but through a more complex transformation. The blowup in the program size is linear in this case.
Reimagining Access to Justice in the Poor People’s Courts

Access to justice efforts have been focused more on access than justice, due in part to the framing of access to justice issues around the presence or absence of lawyers. This article argues that access to justice scholars and activists should also think about social justice and provides a roadmap for running a legal services program geared toward making court systems more just. Building from an in-depth history of family courts, the article also further develops the concept of “poor people’s courts,” a term that has been used to describe courts serving large numbers of low-income people without representation. The article argues that access to justice efforts can and should prioritize responses that address the unique, subordinating impacts of these courts, including those relating to race, class and gender bias, state intervention, and the punitive effects of intersecting state systems. In this context, the article proposes a new theory of access to justice as a counter-hegemonic practice; one that is aimed at challenging dominant ideologies and transforming subordinating systems, as well as delivering legal services.
5' CpG island methylation of the FHIT gene is correlated with loss of gene expression in lung and breast cancer.

Allele loss and loss of expression of fragile histidine triad (FHIT), a putative tumor suppressor gene located in chromosome region 3p14.2, are frequent in several types of cancers. Tumor-acquired methylation of promoter region CpG islands is one method for silencing tumor suppressor genes. We investigated 5′ CpG island methylation of the FHIT gene in 107 primary non-small cell lung cancer (NSCLC) samples and corresponding nonmalignant lung tissues, 39 primary breast carcinomas, as well as in 49 lung and 22 breast cancer cell lines by a methylation-specific PCR assay. In addition, we analyzed brushes from the bronchial epithelium of 35 heavy smokers without cancer. FHIT methylation was detected in 37% of primary NSCLCs, 31% of primary breast cancers, and 65% of lung and 86% of breast cancer cell lines. The frequency of methylation in small cell and NSCLC cell lines were identical. Methylation was found in 9% of the corresponding nonmalignant lung tissues and in 17% of bronchial brushes from heavy cigarette smokers. FHIT methylation was significantly correlated with loss of FHIT mRNA expression by Northern blot analysis in lung cancer cell lines and with loss of Fhit expression in NSCLC and breast tumors by immunostaining. We conclude that methylation of FHIT is a frequent event in NSCLC and breast cancers and is an important mechanism for loss of expression of this gene. Methylation of FHIT commences during lung cancer pathogenesis and may represent a marker for risk assessment.
Velocity-spectrum testing using a closed kinetic chain

Two force and two power variables were monitored during standardized multiple-joint, closed-chain, velocity-spectrum tests to ascertain if contiguous velocities produced discrete or redundant output. Measurements were obtained from 52 men and 50 women during squats performed at six velocities ranging from 0.51 to 2.04 m· S-l. Main effects as well as the sex-by-main-effects interaction were significant (P < 0.001) for all four variables. Therefore, post hoc tests were performed separately for men and women. Maximal squatting forces over the velocity spectrum produced force-velocity curves resembling classical single-joint ones. The highest force output occurred at the slowest test velocity as expected and signifcantly decreased (P < 0.05) for each increment in velocity for both men and women. Concurrently, maximal squatting power over the velocity spectrum produced power-velocity curves resembling classical single-joint ones. The highest power output (x = 1.26 m . S-l) occurred as part of a plateau at intermediate velocities as expected and was signifcantly less at faster and slower velocities. However, maximal power output generally materialized at faster velocities for men (x = 1.54 m·s- 1 ) than for women (x = 0.97 m·s- 1 ). It appears the six squatting velocities used in this investigation elicit discrete force data for both men and women, and results for force and power resemble what would be expected for isolated single-joint testing protocols. However, it remains unclear why an apparent gender difference exists in the velocity at which the highest peak power is produced.
Short Chain Fatty Acids and Colon Cancer

The development of intestinal cancer involves complex genetic and epigenetic alterations in the intestinal mucosa. The principal signaling pathway responsible for the initiation of tumor formation, the APC-beta-catenin-TCF4 pathway, regulates both cell proliferation and colonic cell differentiation, but many other intrinsic and extrinsic signals also modulate these cell maturation pathways. The challenge is to understand how signaling and cell maturation are also modulated by nutritional agents. Through gene expression profiling, we have gained insight into the mechanisms by which short chain fatty acids regulate these pathways and the differences in response of gene programs, and of the specific regulation of the c-myc gene, to physiological regulators of intestinal cell maturation, such as butyrate, compared with pharmacological regulators such as the nonsteroidal antiinflammatory drug sulindac. Moreover, we used a combination of gene expression profiling of the response of cells in culture to sulindac and the response of the human mucosa in subjects treated with sulindac for 1 month, coupled with a mouse genetic model approach, to identify the cyclin dependent kinase inhibitor p21(WAF1/Cip1) as an important suppressor of Apc-initiated intestinal tumor formation and a necessary component for tumor inhibition by sulindac. Finally, the mucous barrier, secreted by intestinal goblet cells, is the interface between the luminal contents and the intestinal mucosa. We generated a mouse genetic model with a targeted inactivation of the Muc2 gene that encodes the major intestinal mucin. These mice have no recognizable goblet cells due to the failure of cells to synthesize and store mucin. This leads to perturbations in intestinal crypt architecture, increased cellular proliferation and rates of cell migration, decreased apoptosis and development of adenomas and adenocarcinomas in the small and large intestine and the rectum.
First macrofossil record of Begonia (Begoniaceae)

PREMISE OF THE STUDY: Begonia is the sixth-largest genus of flowering plants, with about 1400-1500 species in 66 sections. Several species are popular with horticulturalists, mainly for their colorful flowers and leaves. However, the evolutionary history of the genus is debated, and until now there has been no macrofossil record. Here, we report on a fossil winged capsule from the Pliocene of Alabama and interpret it as a Begonia fruit, which represents the first convincing macrofossil evidence of the genus. METHODS: Identification required extensive literature and herbarium searches to compare features of the fossil with those of other recognized fossil and extant taxa that have winged fruits. KEY RESULTS: The fossil is identified as a Begonia fruit on the basis of a combination of characters, including the presence of two unequally developed wings, at least one additional inferred wing, details of the wing venation, a prominent marginal vein, a locule opening associated with a wing, and a persistent pedicel. CONCLUSIONS: Although too young to provide a calibration point for molecular divergence-time estimates, this fossil is noteworthy as the first macrofossil record of Begonia. It may represent a species that initially arrived from the south via Mexico after the closing of the Central American Straits. We propose that this fossil should stimulate a reexamination of other unidentified fossil winged fruits, as older records of Begonia may be forthcoming.
The GH/IGF-1 axis in ageing and longevity

Secretion of growth hormone (GH), and consequently that of insulin-like growth factor 1 (IGF-1), declines over time until only low levels can be detected in individuals aged ≥60 years. This phenomenon, which is known as the 'somatopause', has led to recombinant human GH being widely promoted and abused as an antiageing drug, despite lack of evidence of efficacy. By contrast, several mutations that decrease the tone of the GH/IGF-1 axis are associated with extended longevity in mice. In humans, corresponding or similar mutations have been identified, but whether these mutations alter longevity has yet to be established. The powerful effect of reduced GH activity on lifespan extension in mice has generated the hypothesis that pharmaceutically inhibiting, rather than increasing, GH action might delay ageing. Moreover, mice as well as humans with reduced activity of the GH/IGF-1 axis are protected from cancer and diabetes mellitus, two major ageing-related morbidities. Here, we review data on mouse strains with alterations in the GH/IGF-1 axis and their effects on lifespan. The outcome of corresponding or similar mutations in humans is described, as well as the potential mechanisms underlying increased longevity and the therapeutic benefits and risks of medical disruption of the GH/IGF-1 axis in humans.
Atom transfer radical polymerization from nanoparticles: a tool for the preparation of well-defined hybrid nanostructures and for understanding the chemistry of controlled/"living" radical polymerizations from surfaces.

Structurally well-defined polymer−nanoparticle hybrids were prepared by modifying the surface of silica nanoparticles with initiators for atom transfer radical polymerization and by using these initiator-modified nanoparticles as macroinitiators. Well-defined polymer chains were grown from the nanoparticle surfaces to yield individual particles composed of a silica core and a well-defined, densely grafted outer polystyrene or poly(methyl methacrylate) layer. In both cases, linear kinetic plots, linear plots of molecular weight (Mn) versus conversion, increases in hydrodynamic diameter with increasing conversion, and narrow molecular weight distributions (Mw/Mn) for the grafted polymer samples were observed. Polymerizations of styrene from smaller (75-nm-diameter) silica nanoparticles exhibited good molecular weight control, while polymerizations of methyl methacrylate (MMA) from the same nanoparticles exhibited good molecular weight control only when a small amount of free initiator was added to the polym...
The Brf1 and Bdp1 Subunits of Transcription Factor TFIIIB Bind to Overlapping Sites in the Tetratricopeptide Repeats of Tfc4

The RNA polymerase III initiation factor TFIIIB is assembled onto DNA through interactions involving the Tfc4 subunit of the assembly factor TFIIIC and two subunits of TFIIIB, Brf1 and Bdp1. Tfc4 contains two arrays of tetratricopeptide repeats (TPRs), each of which provides a binding site for Brf1. Dominant mutations in the ligand binding channel of the first TPR array, TPRs1–5, and on the back side of this array, increase Brf1 binding by Tfc4. Here we examine the biological importance of the second TPR array, TPRs6 –9. Radical mutations at phylogenetically conserved residues in the ligand binding channel of TPRs6 –9 impair pol III reporter gene transcription. Biochemical studies on one such mutation, L469K in TPR7, revealed a defect in the recruitment of Brf1 into TFIIIB-TFIIIC-DNA complexes and diminished the direct interaction between Tfc4 and Brf1. Multicopy suppression analysis implicates TPR9 in Brf1 binding and TPRs7 and 8 in binding to more than one ligand. Indeed, the L469K mutation also decreased the binding affinity for Bdp1 incorporation into TFIIIB-TFIIIC-DNA complexes and inhibited binary interactions between Bdp1 and Tfc4. The Bdp1 binding domain in Tfc4 was mapped to TPRs1–9, a domain that contains both TPR arrays and thus overlaps two of the known binding sites for Brf1. The properties of the L469K mutation identify both Brf1 and Bdp1 as ligands for the second TPR array.
INDICATORS OF PUBLIC ATTITUDES TOWARD SCIENCE AND TECHNOLOGY

The use of attitude surveys inScience Indicators — 1976 is reviewed and found sufficiently flawed to limit the utility of survey results. The primary confusion throughout is the treatment of science and technology as if they were indistinguishable activities. Suggestions for conceptual improvement are presented both for describing attitudes and for predicting changes in them.
Clinical Variables Influencing Treatment Decisions for Agitated Dementia Patients: Survey of Physician Judgments

OBJECTIVE: To better understand primary treatment recommendations and the variables that might influence treatment decisions of physicians who treat agitated dementia patients. DESIGN: A written cross-sectional survey of three physician groups (geriatric psychiatrists, primary care physicians, and neurologists) who typically treat agitated dementia patients in community settings. We used a written clinical vignette describing a home-bound, agitated dementia patient to ask respondents to provide information regarding their primary treatment recommendation and to estimate the degree to which clinically relevant variables might influence their treatment recommendation. Using principal component analysis, the original set of clinical variables was collapsed into a smaller set of composite factors that better defined the fundamental constructs of the variables that influenced decision making. Analyses compared primary treatment recommendations and factors influencing treatment recommendations by physician groups. PARTICIPANTS: The pool of survey respondents consisted of a random selection of 207 primary care physicians from western North Carolina, 147 geriatric psychiatrists obtained from the roster of the 1991 American Association for Geriatric Psychiatry, and 120 neurologists obtained from the roster of the American Board of Medical Specialties. The response rate was 65% for geriatric psychiatrists, 38% for primary care physicians, and 33% for neurologists. RESULTS: Differences in primary treatment recommendations by physician group were not found. Physicians, regardless of specialty, recommended neuroleptic medications as their primary intervention. When medication classes were collapsed into a single category, medications as a primary intervention exceeded 55% for all physician groups. Twenty-two percent of all respondents recommended psychosocial interventions as primary treatment strategies. The principal component analysis of clinical variables influencing treatment recommendations solved for five components that accounted for 64% of the variance. Comparing the five components by specialty groups failed to find significant differences, except for Factor 5, the “Hassle Factor.” Primary care physicians were more likely to indicate that this component influenced their decision making than were the other physician groups. CONCLUSIONS: The findings indicate that physicians, regardless of specialty, are likely to use medication and to weight clinically relevant information in a similar fashion when managing agitated dementia patients. J Am Geriatr Soc 44:1375–1379, 1996.
Sneaky plasticity and mesoscopic fractals

Abstract Precise measurement of plastic deformations in many materials show step-like variations or the Portevin-Le Chatelier effect. This serrated yielding is presumed to be due to intermittent slipping and locking of microstructural elements. The conventional macroscopic description of plasticity can be extended to include these processes by introducing singular functions whose integrals and derivatives are not constrained by the fundamental theorem of calculus. As an illustrative example we consider a rigid-perfectly plastic body whose energy includes a singular component that is strictly monotonic, fractal, and whose derivative vanishes almost everywhere.
Deciphering the export pathway of malaria surface proteins

The intra-erythrocytic stages of Plasmodium falciparum assemble a unique protein trafficking system that targets parasite proteins to the red cell cytoplasm and cell surface. It is through this trafficking pathway that the primary virulence determinants of P. falciparum infections are targeted to the erythrocyte surface to mediate adhesion to host endothelial cells. A recent study has shown that SBP-1, a parasite protein associated with Maurer's clefts in the infected red cell cytosol, is essential for transport of the virulence factor PfEMP-1. This discovery sheds new light on the little-understood mechanisms that regulate protein trafficking in infected cells.
Densities, viscosities, refractive indices, and surface tensions for binary and ternary mixtures of 2-propanol, tetrahydropyran, and 2,2,4-trimethylpentane

Abstract Densities, viscosities, refractive indices, and surface tensions of the ternary system (2-propanol + tetrahydropyran + 2,2,4-trimethylpentane) at T = 303.15 K and its constituent binary systems (2-propanol + tetrahydropyran, 2-propanol + 2,2,4-trimethylpentane, and tetrahydropyran + 2,2,4-trimethylpentane) at T = (293.15, 303.15, 313.15, and 323.15) K were measured at atmospheric pressure. Densities were determined using a vibrating-tube densimeter. Viscosities were measured with an automatic microviscometer based on the rolling-ball principle. Refractive indexes were measured using a digital Abbe-type refractometer. Surface tensions were determined by the Wilhelmy-plate method. From these data, excess molar volumes, deviations in viscosity, deviations in refractive index, and deviations in surface tension were calculated. The results for the binary and ternary systems were fitted to the Redlich–Kister equation and the variable-degree polynomials in terms of compositions, respectively. The experimental and calculated quantities are used to study the nature of mixing behaviour between mixture components.
Clinician confidence in coping with patient aggression: Assessment and enhancement.

Training programs intended to enhance clinician confidence in coping with patient aggression have been only cursorily researched. In previous studies researchers have typically used ad hoc instrumentation and have omitted control conditions and follow-up assessment. This investigation included psych
TWO-DIMENSIONAL VORTEX-INDUCED VIBRATION OF CABLE SUSPENSIONS

Abstract Resonant responses of suspended elastic cables driven by a steady current are investigated. Phenomenological fluid force models for alternate vortex-shedding are coupled with the nonlinear partial differential equations of cable motion. Decoupled cross-flow and in-line vortex-induced vibrations (VIV) are examined first using linearized and nonlinear cable models. The linearized cable model predicts well the basic characteristics of VIV and the nonlinear cable model captures the hysteresis often observed in experiments. Next, coupled cross-flow and in-line vibrations are evaluated by considering two principal coupling mechanisms: (i) cable structural nonlinearities, and (ii) coupled fluid lift and drag. Attention is focused on a “worst-case” resonant response where the natural frequencies for cable modes in the cross-flow and in-line directions are in the same 1:2 ratio as the excitation frequencies associated with lift and drag. The inclusion of cable structural nonlinearities alone leads to coupled responses that differ qualitatively (i.e., in number and stability of periodic motions) when compared to those of the decoupled model. The inclusion of coupled fluid lift and drag produces non-planar “figure eight” motions of the cable cross-section that exhibit similar characteristics to those previously measured on spring supported cylinders.
Selective inhibition of embryonic deoxyribonucleic acid synthesis by vinblastine.

Vinblastine inhibits the synthesis of DNA in mouse fetuses in utero, the incorporation of tritiated thymidine into the gut of the parent is, however, not altered. This selective effect, although found with other spindle inhibitors, is not due to the mitotic arresting property of the drug.
The pragmatics of the Chinese nominal marker de 的: 我的爸爸 “my dad” versus 我爸爸 “my dad”

Previous studies of the Chinese nominal marker de 的 attempted to explain its optionality in ways that have fallen short in providing a full account. In this paper, a comprehensive nominal continuum is hypothesized with proper nouns and common nouns prohibiting the use of an internal de at one end. In the middle of the continuum, depending on the degree of lexicalization, there are compounds that may have word-like (no de option) or phrase-like (with de option) properties. At the other end are noun phrases that have individual member, or members, of a type/set readings. The more a compound is lexicalized into a word, the less likely de can occur in front of its determinatum. Whereas the use of 我的爸爸 “my dad” is more likely in a title for its thematic importance, the use of 我爸爸 “my dad” is found tied to its uniqueness in a discourse context.
Assembly of the vesicular stomatitis virus envelope: incorporation of viral polypeptides into the host plasma membrane.

Abstract Incorporation of viral polypeptides into the host plasma membrane is an essential step in the formation of the lipoprotein envelope of vesicular stomatitis virus. A quantitative study of this process was carried out using a double-isotope labeling procedure. Infected cells were incubated for two hours with 14C-labeled amino acids, pulse-labeled with [3H]leucine and incubated for various times with an excess of non-radioactive leucine. The 3 H 14 C ratio was determined for each viral polypeptide in isolated plasma membranes and in the whole cell by polyacrylamide gel electrophoresis. It was found that [3H]leucine-labeled viral polypeptides could be detected in the plasma membranes immediately following a 30-second pulse but that the 3 H 14 C ratios of polypeptides in the plasma membrane did not reach the 3 H 14 C ratios in the whole cells until the end of a two-minute chase period. The addition of puromycin to the cultures at the end of the pulse period did not affect subsequent incorporation of [3H]leucine-labeled polypeptides into the plasma membrane. The incorporation of various amino acid analogs into the viral polypeptides did not affect the efficiency with which they were incorporated into the plasma membranes. It is proposed that viral polypeptides are selected for incorporation into the plasma membrane from a small interior pool of completed molecules.
Analyst following and count-data econometrics

Abstract This paper reexamines the determinants of the number of analysts following a firm using econometric models based on count distributions. We replicate Bhushan's (1989) analyst-following study to demonstrate the effects of using count-data econometrics, in lieu of OLS, in studying phenomena where the dependent variable ranges among nonnegative integers. In contrast with the original paper, our findings indicate the number of institutional investors is inversely related with analyst following. We also provide econometric evidence to support the preferred use of the negative binomial model in estimating cross-sectional, analyst-following regressions.
905-58 Multivessel Disease by Dobutamine Echocardiography is as Predictive as Angiographic Multivessel Disease for Adverse Outcome After Acute Myocardial Infarction

Multivessel coronary artery disease is a powerful predictor of adverse outcome after acute myocardial infarction. To determine whether multiple wall motion abnormalities during dobutamine echocardiography are as predictive as multivessel disease for adverse outcome, 72 medically treated patients (age 58 ± 13 yrs, 57 men, 15 women) underwent dobutamine echocardiography and coronary angiography at 5 ± 2 days after acute myocardial infarction and were followed for g 1 year. Forty-one patients had anterior myocardial infarction and 38 Q-wave infarction. Forty-six were treated with thrombolytic therapy. According to the criterion of g50% luminal diameter stenosis, 43 patients had single vessel disease (1 V), 20 two vessel disease (2V) and 9 three vessel disease (3V). According to the standard 16 segment model and vascular distribution, dobutamine echocardiography (peak dose 24 ± 11μg/kg/min, peak HR 111 ± 20 bpm) identified one wall motion abnormality (1V) in 43 patients, two (2V) in 22 patients and three (3V) in 7 patients. Adverse outcomes occurred in 31 patients (cardiac death 5, nonfatal myocardial infarction 4, heart failure 5 and unstable angina requiring revascularization 17). Event rates were: 1V 2V 3V Angiography 30% (13/43) * 50% (10/20) 89% (8/9) Dobutamine Echo 26% (11/43) * 64% (14/22) 86% (6/7) * p l 0.05 versus multivessel disease In conclusion, single vessel disease is predictive of good outcome. Multiple wall motion abnormalities by dobutamine echocardiography are as predictive as angiographic multivessel disease for adverse outcome after acute myocardial infarction.