Miracle-dz/UniFAR-FTUs huggingface dataset:
Impurity Scattering in Carbon Nanotubes Absence of Back Scattering

The effective potential of an impurity in a k · p scheme is derived in two-dimensional graphite sheet. When the potential range is smaller than the lattice constant, it has an off-diagonal matrix element between K and K ′ points comparable to the diagonal element. With the increase of the range, this off-diagonal element decreases rapidly and the diagonal element for envelopes at A and B sites becomes identical. The crossover between these two regimes occurs around the range smaller than the lattice constant. In the latter regime, back scattering between states with + k and - k vanishes identically for the bands crossing the Fermi level in the absence of a magnetic field, leading to an extremely large conductivity. The absence of the back scattering disappears in magnetic fields, giving rise to a huge positive magnetoresistance.
UV metal semiconductor metal detectors - A robust choice for (Al, Ga)N based detectors

UV detection is interesting for combustion optimization, air contamination control, fire and solar blind rocket launching detection. Most of these applications require that UV detectors have a huge dynamic response between UV and the visible, and a very low dark current in the range of the UV flux measured. (Al,Ga)N alloys present a large direct bandgap in this range and therefore can be used as an active region in such detectors. To take advantage of the large Schottky barrier, the good alloy quality, and to avoid any doping problems, we have developed MSM photodetectors. High quality material has been grown with MOCVD and MBE on sapphire substrates. Stress management is employed for aluminum contents up to 65% to reduce crack density. This is correlated with non-ideal features like dark current, sub-bandgap response and non-linearity between photocurrent and optical flux. The spectral selectivity between UV and visible reaches five orders of magnitude. A geometry of inter-digitized fingers is optimized in regards to the peak response. The Schottky barrier and a dielectric passivation result in dark currents lower than 1 fA up to 30 V for a 100 x 100 mum(2) pixel. Consequently, detectivity is mainly limited by shot noise and corresponds to a noise of 500 photons per second and per pixel.
HYDROGEN SAFETY : LAMINAR AND TURBULENT FLAME SPEED OF SPHERICAL FLAME IN A FAN-STIRRED CLOSED VESSEL

The aim of this paper is to report new experimental results on the effect of turbulence on the propagation speed of hydrogen/air flames. To do so, a new experimental setup, spherical bomb, has been designed and built at CNRS-ICARE laboratory to investigate the effect of a given and well-characterized turbulence intensity on the increase of hydrogen/air flame speed. This new facility consists of a spherical vessel equipped (563 mm internal diameter) with 8 motors that can reach a rotation speed of 12 000 rpm. These engines are equipped with fans inside the bomb and when actuated can generate a turbulent flow inside the vessel prior to any ignition. The spherical bomb is equipped with 4 quartz windows (200 mm optical diameter) that allow the use of a PIV diagnostic in order to characterize the turbulence level inside the bomb. These experiments were performed for lean to stoichiometric hydrogen/air mixtures and for a rotation speed from 1000 to 5000 rpm. The PIV measurements showed that a homogeneous and isotropic turbulence is created with a fluctuation speed that can reach 4 m/s at 5000 rpm. Laminar and turbulent flame speeds of lean hydrogen-air mixtures at ambient temperature and pressure were measured using a high speed camera at 19 002 frames per second.
Avian Macrophage and Immune Response: An Overview 1

Macrophages belong to the mononuclear phagocytic system lineage. This cell type is unique in that it is a crucial player in both the innate and adaptive immune responses. The material described in this overview is a brief description of what I presented as a World’s Poultry Science Association-sponsored lecture at the an(
Mutton mortadella supplemented with yacón meal

ABSTRACT: This study evaluated the effect of different yacón meal concentrations (Smallanthus sonchifolia) on the physicochemical, microbiological, and sensory characteristics of four mortadella formulations (F1, F2, F3, and control) prepared with mutton, pork fat, and additives. All formulations met the physicochemical and microbiological standards defined in regulations for mortadella production in Brazil. Control and F1 were the formulations with better acceptance scores, compared with F2 and F3. The judges stated favorable purchase intention for the control, F1 and F2 formulations. Results showed that mutton mortadella supplemented with yacón meal is a promising alternative in the manufacture of healthier meat products.
PERMISSIBLE RESIDUAL DEFORMATION LEVELS FOR BUILDING STRUCTURES CONSIDERING BOTH SAFETY AND HUMAN ELEMENTS

A review of permissible residual deformation levels is undertaken in light of the increased interest in performance-based seismic design and self-centering systems. Permissible residual deformation levels are considered based on functionality, construction tolerances, and safety. Values are defined based on a review of past structural engineering research, post-earthquake reconnaissance, current building codes, and research in the field of psychology. The findings show that there are only a limited number of studies that measured residual drift levels of structures after an earthquake and correlated these to actual damage levels. In general, construction tolerances remain at or below 0.003 rad depending on the type of structural system and material being considered. This value is below the residual drift levels at which non-structural systems start to lose functionality. Research in the field of psychology has also shown that the lower limit at which people can sense an inclination is approximately 0.005 rad above which extended periods of inclination can cause headaches and dizziness. In order to verify these findings and provide further quantitative results, floor inclinations and column tilt of an occupied 40 year old structure are investigated. These results combined with those obtained through the extensive literature review suggest that 0.005 rad is an important engineering index in terms of permissible residual deformation levels.
Mechanical and Physical Properties of Hybrid Cu-Graphite Composites Prepared via Powder Metallurgy Technique

Copper -graphite composites are widely used in a great number of engineering applicationssuch as brushes, switches, sliding bearings, self-lubricating bearings, etc. due to their goodthermal and electrical conductivity and excellent tribological properties as compared with otherstructural materials. There are ongoing attempts in manufacturing copper composites with betterproperties to enhance their efficiency and increase their effective life. Present research aims to prepare hybrid 95wt. % copper –5wt. % graphite composites reinforced with yttria and tin particles by powder metallurgy technique and to study their effects on mechanical and physical properties of the prepared composites. Powder mixture was mixed by ball mill mixer at 100rpm for 120min with (5/1) balls to powder ratio. The powder mixture was cold pressed at 700MPa for 30sec, followed by sintering at 900 ? C for one hour. In the first stage, Yttria(Y2O3) was added with (2, 4, 6, 8, 10) wt% to pure copper (Cu) and to (95%Cu-5%Gr) matrices. Typical composite of this stage was ((95%Cu-5%Gr)-4%Y2O3. In the second stage, tin (Sn) was added with (2, 4, 6, 8, 10) wt% to pure copper and((95%Cu-5%Gr)-4%Y2O3 matrices. Typical composite of this stage was ((95%Cu-5%Gr)-4%Y2O3)-6%Sn. The results showed that hardness and true porosity of the composites increases with increasing yttria content. On the other hand both thermal and electrical conductivity of the composites decreases with increasing yttria content. It was also found that (95 wt.% Cu- 5 wt.% Gr) – Y2O3 composites have always lower wear rate than plain Cu-Y2O3 composites.
When You Talk, I Remain Silent: Spillover Effects of Peers’ Mandatory Disclosures on Firms’ Voluntary Disclosures

We investigate how firms’ disclosure decisions interact. We predict and find that mandating some firms’ disclosures reduces other firms’ voluntary disclosures due to informational spillovers. Consistent with such spillovers, firms reduce their voluntary disclosures more the greater the number of peers from which firms and their stakeholders can learn and hide. These results hold for a number of alternative disclosure measures and our identifying assumptions receive empirical support across several in- and out-of-sample validation tests.
Study of a Hybrid Excitation Synchronous Machine: Modeling and Experimental Validation

This paper deals with a parallel hybrid excitation synchronous machine (HESM). First, an expanded literature review of hybrid/double excitation machines is provided. Then, the structural topology and principles of operation of the hybrid excitation machine are examined. With the aim of validating the double excitation principle of the topology studied in this paper, the construction of a prototype is presented. In addition, both the 3D finite element method (FEM) and 3D magnetic equivalent circuit (MEC) model are used to model the machine. The flux control capability in the open-circuit condition and results of the developed models are validated by comparison with experimental measurements. The reluctance network model is created from a mesh of the studied domain. The meshing technique aims to combine advantages of finite element modeling, i.e., genericity and expert magnetic equivalent circuit models, i.e., reduced computation time. It also allows taking the non-linear characteristics of ferromagnetic materials into consideration. The machine prototype is tested to validate the predicted results. By confronting results from both modeling techniques and measurements, it is shown that the magnetic equivalent circuit model exhibits fairly accurate results when compared to the 3D finite element method with a gain in computation time.
Molecular dynamics simulations of low-energy (25–200 eV) argon ion interactions with silicon surfaces: Sputter yields and product formation pathways

The etch yield and subsurface damage are important issues in low energy (200 < eV) ion interactions with surfaces. In particular, atomic layer etching requires etching of electronic materials with monolayer precision and minimal interlayer atomic mixing. In this study, the molecular dynamics technique is used to simulate the impact of argon ions on chlorine-free and chlorine-passivated silicon surfaces, under conditions relevant to atomic layer etching. Thousands of individual ion impact simulations are performed on a massively parallel supercomputer. The silicon sputter yield is obtained for Ar ion energies ranging from 25 to 200 eV. Where possible, simulation results are compared to available experimental data. Volatile product formation during ion bombardment of ordered surfaces tends to follow distinct local trajectories. For example, the formation of products due to 120 eV Ar ions impacting onto Si(001)(2×1) at normal incidence has been found to occur mainly by a mechanism in which the Ar ion impacts.
Energy Dissipation rate parameter in a rough wall turbulent boundary layer

The dimensionless mean energy dissipation rate parameter Cε is measured in a fully rough wall turbulent boundary layer at several Reynolds numbers using hot-wire anemometry. The study aims to determine the dependence of Cε = εL/u′3 on the distance from the wall and the Reynolds number. The results shows that Cε decreases as the distance from the wall increases and reaches a minimum value, which appears to be independent of the Reynolds number. Further, this value, which is about 0.40. 5, is the same as in homogeneous isotropic turbulence at high Reynolds numbers. This lends support to the possibility that a universal value for Cε at large Reynolds numbers cannot be ruled out.
Spatial correlations of Rydberg excitations in optically driven atomic ensembles

We study the emergence of many-body correlations in the stationary state of continuously-driven, strongly-interacting dissipative system. Specifically, we examine resonant optical excitations of Rydberg states of atoms interacting via long-range dipole-dipole and van der Waals potentials employing exact numerical solutions of the density matrix equations and Monte-Carlo simulations. Collection of atoms within a blockade distance form a "superatom" that can accommodate at most one Rydberg excitation. The superatom excitation probability saturates to 1/2 for coherently driven atoms, but is significantly higher for incoherent driving, approaching unity as the number of atoms increases. In the steady state of uniformly-driven, extended one-dimensional system, the saturation of superatoms leads to quasi-crystallization of Rydberg excitations whose correlations exhibit damped spatial oscillations. The behavior of the system under the van der Waals interaction potential can be approximated by an analytically soluble model based on a "hard-rod" interatomic potential.
Health Effects of Pesticide Use among Vegetable farmer in Kenya

Paper investigates the determinants of pesticide related Cost of Illness (COI), and acute symptoms, using a balanced panel of 363 farmers interviewed in 2005 and 2008. Finding shows that the incidences of pesticide-related health impairments have increased. Variation in number of symptoms and symptom severity significantly explained COI. The Personal Protective Equipment (PPE), education level, record keeping and geographical location considerably determined health impairments. Encouraging the proper use of PPE and record keeping of pesticide use could great reduce poisoning cases and COI.
Prethermalization in the cooling dynamics of an impurity in a Bose-Einstein condensate

We discuss the cooling dynamics of heavy impurity atoms in a Bose-Einstein condensate (BEC) by emission of Cherenkov phonons from scattering with the condensate. In a weakly interacting, low-temperature condensate the superfluidity of the condensate results in a separation of time-scales of the thermalization dynamics. Pre-thermalized states are formed with distinct regions of impurity momenta determined by the mass ratio of impurity and BEC atoms. This can be employed to detect the mass renormalization of the impurity upon the formation of a polaron and paves the way to preparing non-equilibrium impurity-momentum distributions.
Time and numbers on the fingers: Dissociating the mental timeline and mental number line

People use space to conceptualize abstract domains like time and number. This tendency may be a cognitive universal, but the specifics of people’s implicit space-time and space-number associations vary across cultures. How does culture shape our abstract concepts? In Western cultures, both time and numbers are arranged in people’s minds along an imaginary horizontal line, from left to right, but in other cultures the directions of the mental timeline (MTL) and mental number line (MNL) are reversed. The directions of both the MTL and MNL have long been assumed to depend on the direction in which people read and write text. Here we argue that this assumption is false, and show that the MTL and MNL are shaped by different aspects of cultural experience. In a training experiment, participants spatialized time and numbers in opposite directions across their fingers. Training changed the MTL and MNL in opposite directions, as predicted by a general principle called the CORrelations in Experience (CORE) principle: people spatialize abstract conceptual domains in their minds according to the ways these domains are spatialized in their experience.
Effects of spring temperatures on the strength of selection on timing of reproduction in a long-distance migratory

Microbial invasion of egg contents is a cause of embryonic death. To counter infection risks, the embryo is protected physically by the eggshell and chemically by antimicrobial proteins. If microbial pressure drives embryo mortality, then females may have evolved, through natural selection, to adapt their immune investment into eggs. Although frequently hypothesized, this match between immune allocation and microorganisms has not been explored yet. To examine if correlations between microbes on eggs and immunity in eggs exist, we collected eggs from red-capped larks (Calandrella cinerea) and simultaneously examined their bacterial communities and antimicrobial components—pH, lysozyme and ovotransferrin—during natural incubation. Using molecular techniques, we find that bacterial communities are highly dynamic: bacterial abundance increases from the onset to late incubation, Shannon’s α-diversity index increases during early incubation stages, and β-diversity analysis shows that communities from 1 day-old clutches are phylogenetically more similar to each other than the older ones. Regarding the antimicrobials, we notice a decrease of pH and lysozyme concentration, while ovotransferrin concentration increases during incubation. Interestingly, we show that two eggs of the same clutch share equivalent immune protection, independent of clutch age. Lastly, our results provide limited evidence of significant correlation between antimicrobial compounds and bacterial communities. Our study examined simultaneously, for the first time in a wild bird, the dynamics of bacterial communities present on eggshells and of albumen-associated antimicrobial components during incubation and investigated their relationship. However, the link between microorganisms and immunity of eggs remains to be elucidated further. Identifying invading microbes and their roles in embryo mortality, as well as understanding the role of the eggshell microbiome, might be key to better understand avian strategies of immune maternal investment. PLOS ONE | DOI:10.1371/journal.pone. 0121716 April 16, 2015 1 / 20 a11111
SUGARCANE RESPONSES TO N FERTILIZER APPLICATION ON CLAY SOILS

Sugarcane fertilization practices have been developed for the Rio Grande Valley of Texas based on numerous studies; however, few have been conducted on clay soils. Nitrogen has been found to be the primary nutrient needed, and responses to N fertilization have been limited in the plant-cane crop and increase incrementally in succeeding ratoons to its highest level in the second and following ratoons. This study was conducted to evaluate the effect of rate and timing of N fertilizer application on sugarcane growth, and to determine optimum fertilization practices for sugarcane yield on clay soils. As in previous studies, responses to N application did not occur in the plant cane crop, but were observed in the first through third ratoons. Increasing rate of N application improved stalk population, stalk growth rate, leaf area index, cane yield and sugar yield. Early N application resulted in depletion of available N before full growth potential had been reached, possibly to microbial immobilization or leaching. Late fertilizer application caused a loss of early growth, an effect that was mostly, but not entirely, compensated for by later growth. Soil NO3 -N levels varied little even though yield responses to N fertilization indicated that there were some dramatic differences in soil N availability and residual levels. Increasing N application had detrimental effects on sugarcane juice quality, but the magnitude of the effects were small compared to increasing cane growth responses, therefore sugar yield continued to increase as N application increased. Early fertilizer application resulted in lower sugar yield due to lower cane yield, while late fertilizer application resulted in lower sugar yields due to lower juice quality rather than any loss in growth. Nitrogen fertilizer application to sugarcane on clay soils in subtropical South Texas is not required on plant cane crops, and should be at least at or above the level of 224 kg ha -1 used in this study in ratoon crops. Timing of a single application should be in March or April, or split into 2-3 applications on clay soils. YIELD COMPONENTS OF SUGARCANE SUBJECTED TO FLOOD AT PLANTING 1 C.W. Deren and R.N. Raid University of Florida/IFAS Everglades Research and Education Center Belle Glade, FL 33430 cwd@gnv.ifas. ufl.edu
Are Voter Decision Rules Endogenous to Parties’ Policy Strategies? A Model with Applications to Elite Depolarization in Post-Thatcher Britain

While spatial modelers assume that citizens evaluate parties on the basis of their policy positions, empirical research on American politics suggests that citizens’ party attachments often drive their policy preferences, rather than vice versa. Building on previous findings that partisanship is less salient to British citizens than to Americans, we argue that British citizens predominantly update their partisanship to match their policy beliefs. We further argue that because policy salience declines when parties converge, citizens’ policy beliefs exert diminishing effects on their party evaluations as parties depolarize on a focal policy dimension—i.e., that voter decision rules are an endogenous function of parties’ policy strategies. We find support for these hypotheses via individual-level analyses of British election panel survey data between 1987 and 2001. We also find that the reciprocal policy-partisan effects we identify extend to different subconstituencies of British citizens including the more and less educated and politically engaged.
Detection and prediction of mean and extreme European summer temperatures with a multimodel ensemble

We analyze observed mean to extreme summer temperature indices across Europe in order to determine whether there is evidence for a detectable climate change signal and whether these indices show evidence for predictability. Observations from 1960 to 2011, taken from E‐OBS an observational dataset created for the European Commission funded project (ENSEMBLES), are compared with the model simulations from the global coupled climate models CanCM4, HadCM3, MIROC5, and MPI‐ESM‐LR, as published on the CMIP5 archive. Indices are examined that span a moderate to extreme range of the summer temperature distribution by including the summer average, the hottest 5day average, and the hottest daily maximum and daily minimum temperatures during summer. The region of interest is Europe; however, a number of subregions are also studied, which include Western Europe, the British Isles, the Mediterranean, and Central Europe. The observed changes in the analyzed indices are well represented by the multimodel mean and are within the range of the multimodel ensemble for most regions, with the exception of 1 and 5day average daily maximum temperature extremes across the UK. Observed changes are detectable against estimates of internal climate variability for both moderate and extreme temperature indices across all regions in almost all cases. Exceptions are the hottest 5day average daily maximum temperature in the UK and Central Europe, for which results are not conclusive. An analysis of the skill in decadal hindcasts of these indices shows that there is significant prediction skill across these indices for three of the four models for some regions and some models. This skill exceeds the skill of forecasts based on observed climatology and random noise and is largely due to external forcing. However, there is some evidence that there is additional skill originating from the assimilation of observations into the initialization in some cases.