Size-dependent mechanical properties of molybdenum nanopillars

We report the deformation behavior of single crystalline molybdenum nanopillars in uniaxial compression, which exhibits a strong size effect called the “smaller is stronger” phenomenon. We show that higher strengths arise from the increase in the yield strength rather than through postyield strain hardening. We find the yield strength at nanoscale to depend strongly on sample size and not on the initial dislocation density, a finding strikingly different from that of the bulk metal

Sex and discipline differences in empathising, systemising and autistic symptomatology : evidence from a student population

Baron-Cohenʹs (2002) theory of autism suggests that deficits in theory of mind and weak central coherence in autism can be explained as features of an ‘extreme male brain’ in which empathising is weak and systemising is strong. The two studies presented investigate this theory by examining the relationships between theory of mind, central coherence, empathising, systemising and autistic-like symptomatology in a sample of undergraduates. Study 1 used 48 undergraduates in four equal groups of male and female science and humanities students. Consistent with the theory, there were sex differences in the expected directions on all tasks in the first study. Differences according to discipline were found only on the Block Design task. Individuals with the ‘male brain’ profile also tended to show higher levels of autistic symptomatology. There was no evidence of a link between empathising and social skills on one hand and systemising and central coherence on the other. In the second study, performance on the Mechanical Reasoning and the Social Skills Inventory tasks was compared with performance on the Baron‐Cohen Empathising and Systemising Quotients in a sub‐sample of 20 students from Study 1. Moderately significant correlations were found between the Systemising Quotient and the Mechanical Reasoning task and between the Empathising Quotient and the Social Skills Inventory. Findings are largely consistent with the distinction between empathising and systemising but raise some questions concerning the tasks used to measure these abilities

A Novel Population of Cardiovascular Progenitors Persist in Neonates as Mesendodermal Cells

The rise in mortality due to cardiovascular disease has increased the need to develop an efficient regenerative therapeutic for heart failure. Numerous cell-based therapies have been investigated for myocardial regeneration; however, an optimal progenitor has yet to be discovered. Identifying a resident cell population with enhanced ability to differentiate into multiple lineages would greatly contribute to the field of stem cell-based regenerative therapy. Evidence suggests that endogenous cardiovascular progenitor cells (CPCs) that have been isolated from the heart itself express ISL1, KDR, and MESP1, and are capable of differentiating into all major cardiac lineages. The earlier developmental stage at which endogenous CPCs reside may be associated with enhanced multipotency and differentiation capacity. A clonal population of human neonatal CPCs expressing markers of early cardiovascular development was therefore selected for analysis. Based upon recent reports of differentiation into osteoblasts by cells expressing ISL1, we performed differentiation of the selected neonatal CPC into cardiovascular lineages as well as the mesodermal derivative, osteoblasts. Gene expression analysis and flow cytometry demonstrated differentiation into both cardiovascular and osteoblast lineages. To further address the relationship between an earlier developmental stage and differentiation capability, we measured the expression of mesendodermal regulatory markers, and discovered that this population of progenitor cells may reside earlier in development than previously recognized. These results suggest that neonatal cardiovascular progenitors expressing transcripts of the mesendoderm persist within the newborn human heart, exhibit enhanced differentiation capacity into various mesodermal lineages, and can be expanded for further assessment of functional and regenerative ability

Input-Output Analysis, Linear Programming and Modified Multipliers

The input-output (IO) analysis explores changes in final demand through the regional economy using multipliers. However, it isn’t flexible to investigate the regional impact from the capacity limitations which are directly imposed on production, not final demand. This is because the multipliers are changing with exogenous restrictions on production. Conventionally, the IO analysis is performed assuming exogenous production restrictions being the changes in final demands or assuming the sector being exogenous sector like the final demand. If researchers or policy makers are interested in only economic impacts from production restrictions, there is no need to look into the modified multipliers. The modified multipliers should be considered when researchers and policy makers attempt to analyze the compensation of impact, especially recovery of loss using government expenditure. We suggest that the linear programming is a useful and efficient tool to derive modified multipliers and estimate correct regional impact from the policy changes.Input-Output Analysis, Multipliers, Regional Impact Analysis, Community/Rural/Urban Development, C67, R15, R5,

Modeling US Counties’ Innovation Capacity with a Focus on Natural Amenities

Innovation Capacity, Natural Amenity, Community/Rural/Urban Development, O31, Q51,

Researcher Access to Born-Digital Collections: an Exploratory Study

While a small, but growing number of institutions offer access to born-digital collections, there is scant literature documenting researcher interaction with these materials. This paper addresses this gap through documenting and analyzing researcher interactions to portions of born-digital collections at New York University (NYU) Libraries, with the cooperation of NYU’s Fales Library and Special Collection and the Digital Library and Technology Solutions Department, as well as the National Digital Stewardship Residency (NDSR) program. From September 2014-May 2015, NYU Libraries began implementing an “access-driven” born-digital workflow for their 3 archives: Fales Library and Special Collections, NYU University Archives, and the Tamiment Library and Robert F. Wagner Archives, using several model collections as part of a 9 month NDSR project. One goal was to provide access to these collections by the end of the project period. The project concluded with 5 researcher interviews investigating how researchers navigate, understand, and value forms of born-digital access. This paper will focus on these interviews and how new forms of access were interpreted and received

The adverse effects of chronic social stress on learning and the role of serotonin quantified by a binary logistic regression model in individual crickets (Gryllus bimaculatus)

The ability to learn and change future behaviour based on past experiences is crucial for the life and survival of animals. For various behaviours exhibited by animals it is clear that in a seemingly homogeneous population not all individuals behave the same way, even in invertebrates. In crickets (Gryllus bimaculatus), a model system for the mechanisms of intra-specific aggression, agonistic experiences with the underlying impact of neuromodulators have been identified as a cause of inter-individual differences. For mammals and humans, the experience of adversity and stress can have detrimental effects on cognitive abilities and chronic defeat stress is used as a model for depression. In crickets the equivalent, the chronic social defeat stress paradigm, has been established. This thesis first sets out to construct a new model for measuring a conditioned response from multiple behavioural aspects and quantify learning in individual crickets. Video tracking of responses revealed behavioural variables that were included in a binary logistic regression analysis, whereas the resulting multi-variable model proves to be superior to other models constructed and can give the probability of an individual exhibiting a conditioned response. With this, learning indices can be calculated for each individual trained in a differential appetitive olfactory paradigm. With the method at hand, this thesis reveals that the experience of chronic social stress impairs learning in crickets, susceptible and resilient to defeat stress alike. The experience of multiple wins, however, does neither improve nor decrease learning abilities, but a long-term winner effect on aggression could be shown. Although inter-individual differences in learning are present, the aggressive state of crickets is not correlated to the learning indices. The application of serotonergic drugs that block receptors or act as re-uptake inhibitors reveal the influence of serotonin on learning within this paradigm. In addition to maintaining reduced aggressiveness, serotonin promotes the impairment of learning after the experience of chronic social defeat stress.:1 INTRODUCTION.....................................................................................................1 2 MATERIALS AND METHODS............................................................................... 8 2.1 Experimental animals...................................................................................... 8 2.2 Appetitive olfactory conditioning..................................................................... 8 2.2.1 Odour application and rewarding....................................................... 8 2.2.2 Absolute conditioning paradigm........................................................ 10 2.2.3 Differential conditioning paradigm.................................................... 11 2.3 Experimental setup for video-tracking.............................................................. 12 2.4 Binary logistic regression model....................................................................... 13 2.4.1 Binary groups for model building...................................................... 13 2.4.2 Variables of a behavioural response................................................... 14 2.4.3 Calculating a conditioned odour response probability (Presp) ............ 15 2.5 Evaluation of learning with the binary logistic model...................................... 17 2.6 Evaluation of aggression with a standardised fight.......................................... 18 2.7 Multiple agonistic experiences......................................................................... 19 2.7.1 Chronic social defeat stress................................................................ 19 2.7.2 Multiple wins..................................................................................... 20 2.8 Serotonin......................................................................................................... 20 2.8.1 Pharmacological treatments............................................................... 20 2.8.2 Methiothepin and ketanserin.............................................................. 21 2.8.3 Fluoxetine with non-chronic defeat................................................... 21 2.9 Additional data analysis and statistic................................................................ 22 3 RESULTS............................................................................................................ 23 3.1 Binary logistic regression model for quantifying learning............................... 23 3.1.1 Behavioural variables of a conditioned odour response.................... 23 3.1.2 Model building and selection............................................................. 29 3.1.3 Odour response probabilities (Presp)................................................... 31 3.1.4 Application of the regression model to assess the quantification of learning.................................................................................................... 34 3.2 The influence of agonistic experiences on aggression and learning................. 39 3.2.1 Chronic social defeat stress................................................................ 39 3.2.2 Multiple experiences of winning........................................................ 46 3.2.3 Correlation of aggression and learning............................................... 48 3.2.4 Summary of learning capacities – multiple experiences.................... 50 3.3 The influence of serotonergic drugs on learning after chronic defeat.............. 51 3.3.1 Methiothepin and ketanserin.............................................................. 51 3.3.2 Fluoxetine........................................................................................... 57 3.3.3 Summary of learning capacities – chronic defeat and serotonin........ 60 4 DISCUSSION....................................................................................................... 63 4.1 The semi-automated measurement of olfactory learning in individually assayed crickets................................................................................................................... 64 4.2 The influence of multiple agonistic experiences on learning........................... 71 4.3 The role of serotonin in chronic social defeat influenced learning................... 77 4.4 Overall conclusion and outlook........................................................................ 80 5 SUMMARY........................................................................................................... 82 6 ZUSAMMENFASSUNG........................................................................................ 87 7 REFERENCES.................................................................................................... 93 8 APPENDIX................................................................................................... 106 8.1 Figures and tables................................................................................... 106 8.2 Publications and published abstracts....................................................... 108 8.3 Curriculum vitae....................................................................................... 109 8.4 Acknowledgements.................................................................................. 11