Synthesis of TCNE and TCNQ Derivatives and the Preparation of Conducting Polymers

Tetracyanoethylene and tetracyanoquinodimethane were reacted with various N,N-dimethyl-a, w-alkyldiamines to produce TCNE and TCNQ diamino and monoamino derivatives. NMR and ir spectra of the monoamino derivatives, 1-(N,N-dimethyl-a,w-alkyldiamino)-1,2,2-tricyanoethylenes and 7-(N,N-dimethyl-a,w-alkyldiamino)-7,8,8-tricyanoquinodimethans, indicated that these compounds exhibited strong nitrogen-hydrogen-nitrogen intramolecular hydrogen bonding. This phenomenon was corroborated by molecular weight and preliminary x-ray analyses. The 1,1-bis(N,N-dimethyl-a,w-alkyldiamino)-2,2-dicyanoethylene and 7,7-bis(N,N-dimethyl-a,m-alkyldiamino)-8,8-dicyanoquinodimethan derivatives were polymerized with a,m-alkyldibromides containing two to six methylene groups to produce the corresponding ionene polymers. Viscosity measurements of the polymers indicated that the TCNE copolymers were generally of higher molecular weight than the corresponding TCNQ copolymers. The two polymer series were treated with lithium tetracyanoquinodi-methanide to produce semiconducting polymers. Electrical measurements indicated that these materials had conductivities on the order of 10-7 ohm-1 cm-1. Treatment of the polymers with neutral TCNQ resulted in increased conductivities ranging from two to five orders of magnitude

River Run Off Measurement With SAR Along Track Interferometry

The paper summarizes the need for global space borne river run-off measurements. It reports about an airborne SAR experiment aimed to measure the surface velocity of the river Isar in Bavaria / Germany. The results from two different SAR techniques, including Along Track Interferometry (ATI) show good correspondence. Finally suggestions for further studies are given

Reducing spectral reflections through image inpainting

Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2009.Includes bibliographical references (p. 45-46).The goal of this thesis is to produce an image processing tool that could, with limited user interaction, significantly reduce spectral reflections. The resulting process can then be used by biological researchers in the process of cataloging and recognizing individual organisms via collected images. The process involves the generation of a mask, refinements to that mask such as background segmentation and morphological dilation, and finally the inpainting of the specular regions. This method improves on existing single pixel methods by incorporating both color and texture infilling of the specular reflections. It also works on images with no special setup or preparation.by Joshua Runge.M.Eng

Evaluation of a Reproductive Index for Estimating Productivity of Grassland Breeding Birds

Declining populations of grassland breeding birds have led to increased efforts to assess habitat quality, typically by estimating density or relative abundance. Because some grassland habitats may function as ecological traps, a more appropriate metric for determining quality is breeding success, which is challenging to determine for many cryptic-nesting grassland birds. This difficulty led Vickery et al. (1992) to propose a reproductive index based on behavioral observations rather than nest fate. We rigorously evaluated the index for 2 years using a Savannah Sparrow (Passerculus sandwichensis) population in western New York and found a weak correlation in classification of the breeding stages of monitored territories among multiple observers (r = 0.398). We also discovered a large difference between overall territory and nest success rates independently estimated with the index (9.8% over the entire breeding cycle) and with nest searching and monitoring (41.7% of nests successfully fledged young). Most importantly, we made territory-level comparisons of index estimates with actual nest fate and found that the index correctly predicted fates for only 43% of the monitored nests. A Mayfield logistic regression analysis demonstrated that only index rank 4 (eggs hatched, but young failed to fledge) showed a strong positive correlation with nest success. Although the reproductive index may function as a coarse indicator of habitat suitability (e.g., documenting production in potential ecological traps), in our study the index exhibited neither internal consistency nor the ability to predict nest fate at the plot or territory level and functioned poorly as a substitute for nest searching and monitoring

An Interferometric SAR Satellite Mission

The paper provides a critical review of the achievements in SAR interferometry from the ERS mission as well as from the Shuttle Radar Topography Mission SRTM. It describes the development from the original idea of the Interferometric Cartwheel to the concept of a formation flight of identical and active SAR satellites. From the experience gained from ERS and SRTM interferometric data processing as well as from the analysis of the Cartwheel concept a list of mission requirements has been set up. The most demanding one is the autonomous configuration flight of a tight x-band constellation, where the satellites fly as close as up to 30 m with a dead-band of +/- 10 m. The guidance, navigation and control considerations come to the conclusion that such a mission is feasible

Typology and function of Late Bronze Age and Early Iron Age cremation graves: a micro-regional case study

In Denmark, there has been little focus on characteristic differences between grave types from the transition period between the Late Bronze Age and the Early Iron Age with limited elaboration on the nature of the differences and on chronological variation. In nearby Scania, Sweden, a grave type classic for Southern Scandinavia, the ‘cremation pit’, has been interpreted as in situ remains of the actual cremation pyre, that is, a form of bustum. Here, we further explore this interpretation through both osteological and archaeological analyses of recently excavated graves from the Fraugde region on northern Funen ,Denmark. In the Fraugde region, pyre debris in cremation graves clearly gain significance during the transition period from the Bronze Age towards the Pre-Roman Iron Age. The exclusive presence of cremation pits on the Pre-Roman Iron Age grave sites in contrast to the varied grave types present on the Bronze Age sites implies a change in cremation practice and technology during the transition period. Although clearly commemorated and left undisturbed for centuries, the cremation pits on the pre-Roman Iron Age sites must be interpreted as intentional, secondary deposits of the debris from the cremation pyre, but not as in situ pyre sites

Assessing Allowable Take of Migratory Birds

Legal removal of migratory birds from the wild occurs for several reasons, including subsistence, sport harvest, damage control, and the pet trade. We argue that harvest theory provides the basis for assessing the impact of authorized take, advance a simplified rendering of harvest theory known as potential biological removal as a useful starting point for assessing take, and demonstrate this approach with a case study of depredation control of black vultures (Coragyps atratus) in Virginia, USA. Based on data from the North American Breeding Bird Survey and other sources, we estimated that the black vulture population in Virginia was 91,190 (95% credible interval = 44,520–212,100) in 2006. Using a simple population model and available estimates of life-history parameters, we estimated the intrinsic rate of growth (rmax) to be in the range 7–14%, with 10.6% a plausible point estimate. For a take program to seek an equilibrium population size on the conservative side of the yield curve, the rate of take needs to be less than that which achieves a maximum sustained yield (0.5 x rmax). Based on the point estimate for rmax and using the lower 60% credible interval for population size to account for uncertainty, these conditions would be met if the take of black vultures in Virginia in 2006 was rmax. Further, the ratio of desired harvest rate to 0.5 x rmax may be a useful metric for ascertaining the applicability of specific requirements of the National Environmental Protection Act

Coaching Efficacy Beliefs and Transformational Leadership Behaviors: Their Ability to Predict Motivational Climate

This study investigated the relationship between belief in coaching abilities (coaching efficacy beliefs, CEB), transformational leadership behaviors (TLB), and motivational climate development of current strength and conditioning coaches working with high school level athletes. The measures used were the coaching efficacy scale for high school teams (CES II-HST, Myers et al.,2000), the differentiated transformational leadership inventory (DTLI, Callow et al., 2009), and the patterns of adaptive learning scales (PALS, Midgley et al., 2000). It was hypothesized that CEB and TLB would influence motivational climate development, while coaches' background characteristics would correlate with CEB, TLB, and motivational climate development. The 60 coaches who participated reported an average of thirteen (SD=8) years of experience and 51 were Certified Strength and Conditioning Specialists. Coaches reported high efficacy, frequent use of TLB, and development of a moderately high task- and somewhat ego-involving motivational climate. Correlations between demographic variables and CEB, TLB, and motivational climate development revealed three significant relationships: years of experience with CEB, and professional development activities and athlete to coach ratio with ego-involving climate development. CEB and TLB had a strong positive correlation. Two regression analyses were conducted to determine if the outcomes of the CEB and TLB measures predicted motivational climate development. The only significant predictor was TLB positively predicting development of a task-involving motivational climate. Strength coaches can utilize the findings of this study help shape their leadership behaviors and develop a task-involving motivational climate that emphasizes effort, improvement, and cooperative learning and is optimal for athlete development and performance

Spatial distribution of electric-field enhancement across the gap of terahertz bow-tie antennas

The electric-field enhancement in terahertz (THz) antennas designed for nonlinear THz spectroscopy of soft matter is characterized by spatially resolved electrooptic sampling. To mimic the relevant interaction geometry, metallic, resonant bow-tie antennas are deposited on a thin zinc telluride crystal of 10 µm thickness. The THz electric field transmitted through the antenna gap is recorded by electrooptic sampling. By focusing the 800 nm, sub-20 fs sampling pulses, we achieve a spatial resolution of some 3 µm, which is 1/3 to 1/8 of the antenna-gap width. The THz field in the gap displays an enhancement by a factor of up to 4.5 with a pronounced spectral variation, depending sensitively on the antenna-arm length and the gap width. By scanning the 800 nm probe spot laterally through the antenna gap, the spatial variation of the enhancement is determined, reaching the highest values at the edges of the gap. The results are in agreement with simulations of the electric-field distributions by finite-element calculations. © 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreemen

Real-world heart rate norms in the Health eHeart study.

Emerging technology allows patients to measure and record their heart rate (HR) remotely by photoplethysmography (PPG) using smart devices like smartphones. However, the validity and expected distribution of such measurements are unclear, making it difficult for physicians to help patients interpret real-world, remote and on-demand HR measurements. Our goal was to validate HR-PPG, measured using a smartphone app, against HR-electrocardiogram (ECG) measurements and describe out-of-clinic, real-world, HR-PPG values according to age, demographics, body mass index, physical activity level, and disease. To validate the measurements, we obtained simultaneous HR-PPG and HR-ECG in 50 consecutive patients at our cardiology clinic. We then used data from participants enrolled in the Health eHeart cohort between 1 April 2014 and 30 April 2018 to derive real-world norms of HR-PPG according to demographics and medical conditions. HR-PPG and HR-ECG were highly correlated (Intraclass correlation = 0.90). A total of 66,788 Health eHeart Study participants contributed 3,144,332 HR-PPG measurements. The mean real-world HR was 79.1 bpm ± 14.5. The 95th percentile of real-world HR was ≤110 in individuals aged 18-45, ≤100 in those aged 45-60 and ≤95 bpm in individuals older than 60 years old. In multivariable linear regression, the number of medical conditions, female gender, increasing body mass index, and being Hispanic was associated with an increased HR, whereas increasing age was associated with a reduced HR. Our study provides the largest real-world norms for remotely obtained, real-world HR according to various strata and they may help physicians interpret and engage with patients presenting such data