B627: The Relation of Tree and Stand Characteristics to Basal Area Growth of Red Spruce Trees in Partially Cut Stands in Eastern Maine

This bulletin reports on a study that evaluated the relationship of red spruce tree growth to various tree and stand conditions. Some of the tree characteristics selected for this study were initial dbh., live crown length, total height, total age at dbh, and the periodic basal area growth five years prior to partial cutting. Stand conditions that were considered included basal area per acre and the number of trees per acre, since both are relative measures of the competition between trees on any given area. The relationships between these factors would be useful in assessing the potential of any given tree or group of trees.https://digitalcommons.library.umaine.edu/aes_bulletin/1043/thumbnail.jp

B614: A Plan for the Recreational Development of the Machias Lakes Region in Washington County, Maine

The importance of forest land as the medium for wood fiber production has been recognized for some time. Recent developments and trends show that another function of this same forest land is that of providing a playground for millions of outdoor recreationists. This phenomenon has affected some areas to such an extent that certain forest lands are now considered to be more valuable as sources of outdoor recreation than as wood fiber production units. This bulletin presents a plan for landowners of a 90,000-acre tract of commercial forest land located midway between Bangor and Calais, Maine, in Washington County, to more completely utilize the recreational resource. In addition, it is proposed that the service provided would be such that an income could be expected in the form of a recreation use fee. It is not the intent of this report to advocate the allocation of 90,000 acres of commercial forest land for recreation pursuits alone. Rather, it is an attempt to illustrate the fact that the intensive recreational use of an area removes little land from timber production and increases the total satisfaction that may be realized from a specific tract of forest land.https://digitalcommons.library.umaine.edu/aes_bulletin/1059/thumbnail.jp

Cyber-Physical Security with RF Fingerprint Classification through Distance Measure Extensions of Generalized Relevance Learning Vector Quantization

Radio frequency (RF) fingerprinting extracts fingerprint features from RF signals to protect against masquerade attacks by enabling reliable authentication of communication devices at the “serial number” level. Facilitating the reliable authentication of communication devices are machine learning (ML) algorithms which find meaningful statistical differences between measured data. The Generalized Relevance Learning Vector Quantization-Improved (GRLVQI) classifier is one ML algorithm which has shown efficacy for RF fingerprinting device discrimination. GRLVQI extends the Learning Vector Quantization (LVQ) family of “winner take all” classifiers that develop prototype vectors (PVs) which represent data. In LVQ algorithms, distances are computed between exemplars and PVs, and PVs are iteratively moved to accurately represent the data. GRLVQI extends LVQ with a sigmoidal cost function, relevance learning, and PV update logic improvements. However, both LVQ and GRLVQI are limited due to a reliance on squared Euclidean distance measures and a seemingly complex algorithm structure if changes are made to the underlying distance measure. Herein, the authors (1) develop GRLVQI-D (distance), an extension of GRLVQI to consider alternative distance measures and (2) present the Cosine GRLVQI classifier using this framework. To evaluate this framework, the authors consider experimentally collected Z -wave RF signals and develop RF fingerprints to identify devices. Z -wave devices are low-cost, low-power communication technologies seen increasingly in critical infrastructure. Both classification and verification, claimed identity, and performance comparisons are made with the new Cosine GRLVQI algorithm. The results show more robust performance when using the Cosine GRLVQI algorithm when compared with four algorithms in the literature. Additionally, the methodology used to create Cosine GRLVQI is generalizable to alternative measures

International Public Health Research Involving Interpreters: a Case Study from Bangladesh

Background: Cross-cultural and international research are important components of public health research, but the challenges of language barriers and working with interpreters are often overlooked, particularly in the case of qualitative research. Methods: A case-study approach was used to explore experiences of working with an interpreter in Bangladesh as part of a research project investigating women's experiences of emergency obstetric care. The case study: Data from the researcher's field notes provided evidence of experiences in working with an interpreter and show how the model of interviewing was adapted over time to give a more active role to the interpreter. The advantages of a more active role were increased rapport and "flow" in interviews. The disadvantages included reduced control from the researcher's perspective. Some tensions between the researcher and interpreter remained hard to overcome, irrespective of the model used. Independent transcription and translation of the interviews also raised questions around accuracy in translation. Conclusion: The issues examined in this case study have broader implications for public health research. Further work is needed in three areas: 1) developing effective relationships with interpreters; 2) the impact of the interpreter on the research process; and 3) the accuracy of the translation and level of analysis needed in any specific public health research. Finally, this paper highlights the importance to authors of reflecting on the potential impact of translation and interpretation on the research process when disseminating their research

Plasmonically Enhanced Reflectance of Heat Radiation from Low-Bandgap Semiconductor Microinclusions

Increased reflectance from the inclusion of highly scattering particles at low volume fractions in an insulating dielectric offers a promising way to reduce radiative thermal losses at high temperatures. Here, we investigate plasmonic resonance driven enhanced scattering from microinclusions of low-bandgap semiconductors (InP, Si, Ge, PbS, InAs and Te) in an insulating composite to tailor its infrared reflectance for minimizing thermal losses from radiative transfer. To this end, we compute the spectral properties of the microcomposites using Monte Carlo modeling and compare them with results from Fresnel equations. The role of particle size-dependent Mie scattering and absorption efficiencies, and, scattering anisotropy are studied to identify the optimal microinclusion size and material parameters for maximizing the reflectance of the thermal radiation. For composites with Si and Ge microinclusions we obtain reflectance efficiencies of 57 - 65% for the incident blackbody radiation from sources at temperatures in the range 400 - 1600 {\deg}C. Furthermore, we observe a broadbanding of the reflectance spectra from the plasmonic resonances due to charge carriers generated from defect states within the semiconductor bandgap. Our results thus open up the possibility of developing efficient high-temperature thermal insulators through use of the low-bandgap semiconductor microinclusions in insulating dielectrics.Comment: Main article (8 Figures and 2 Tables) + Supporting Information (8 Figures

SEIS: Insight's Seismic Experiment for Internal Structure of Mars.

By the end of 2018, 42 years after the landing of the two Viking seismometers on Mars, InSight will deploy onto Mars' surface the SEIS (Seismic Experiment for Internal Structure) instrument; a six-axes seismometer equipped with both a long-period three-axes Very Broad Band (VBB) instrument and a three-axes short-period (SP) instrument. These six sensors will cover a broad range of the seismic bandwidth, from 0.01 Hz to 50 Hz, with possible extension to longer periods. Data will be transmitted in the form of three continuous VBB components at 2 sample per second (sps), an estimation of the short period energy content from the SP at 1 sps and a continuous compound VBB/SP vertical axis at 10 sps. The continuous streams will be augmented by requested event data with sample rates from 20 to 100 sps. SEIS will improve upon the existing resolution of Viking's Mars seismic monitoring by a factor of ∼ 2500 at 1 Hz and ∼ 200 000 at 0.1 Hz. An additional major improvement is that, contrary to Viking, the seismometers will be deployed via a robotic arm directly onto Mars' surface and will be protected against temperature and wind by highly efficient thermal and wind shielding. Based on existing knowledge of Mars, it is reasonable to infer a moment magnitude detection threshold of M w ∼ 3 at 40 ∘ epicentral distance and a potential to detect several tens of quakes and about five impacts per year. In this paper, we first describe the science goals of the experiment and the rationale used to define its requirements. We then provide a detailed description of the hardware, from the sensors to the deployment system and associated performance, including transfer functions of the seismic sensors and temperature sensors. We conclude by describing the experiment ground segment, including data processing services, outreach and education networks and provide a description of the format to be used for future data distribution.Electronic supplementary materialThe online version of this article (10.1007/s11214-018-0574-6) contains supplementary material, which is available to authorized users

Exploring implications of context specificity and cognitive load in residents

Introduction: Context specificity (CS) refers to the variability in clinical reasoning across different presentations of the same diagnosis. Cognitive load (CL) refers to limitations in working memory that may impact clinicians’ clinical reasoning. CL might be one of the factors that lead to CS. Although CL during clinical reasoning would be expected to be higher in internal medicine residents, CL’s effect on CS in residents has not been studied. Methods: Internal medicine residents watched a series of three cases portrayed on videos. Following each case, participants filled out a post-encounter form and completed a validated measure of CL. Results: Fourteen residents completed all three cases. Across cases, self-reported CL was relatively high and there were small to moderate correlations between CL and performance in clinical reasoning (r’s = .43, -.33, -.23). In terms of changing CL across cases, the correlations between change in CL and change in total performance were statistically significantly only in moving from case 1 to case 2 (r = -.54, p =.05). Discussion and Conclusion: Residents self-reported measurements of CL were relatively high across cases. However, higher CL was not consistently associated with poorer performance. We did observe the expected associations when looking at case-to-case change in CL. This relationship warrants further study

Antiferromagnetic-ferromagnetic phase domain development in nanopatterned FeRh islands

The antiferromagnetic-to-ferromagnetic phase transition in B2-ordered FeRh is imaged in laterally confined nanopatterned islands using photoemission electron microscopy with x-ray magnetic circular dichroism contrast. The resulting magnetic images directly detail the progression in the shape and size of the FM phase domains during heating and cooling through the transition. In 5-μm-square islands this domain development during heating is shown to proceed in three distinct modes—nucleation, growth, and merging—each with subsequently greater energy costs. In 0.5-μm islands, which are smaller than the typical final domain size, the growth mode is stunted and the transition temperature is found to be reduced by 20 K. The modification to the transition temperature is found by high-resolution scanning transmission electron microscopy to be due to a 100-nm chemically disordered edge grain present as a result of ion implantation damage during the patterning. FeRh has unique possibilities for magnetic memory applications; the inevitable changes to its magnetic properties due to subtractive nanofabrication will need to be addressed in future work in order to progress from sheet films to suitable patterned devices

Young pregnant women's views on the acceptability of screening for chlamydia as part of routine antenatal care

<p>Abstract</p> <p>Background</p> <p>In pregnancy, untreated chlamydia infection has been associated with adverse outcomes for both mother and infant. Like most women, pregnant women infected with chlamydia do not report genital symptoms, and are therefore unlikely to be aware of their infection. The aim of this study was to determine the acceptability of screening pregnant women aged 16-25 years for chlamydia as part of routine antenatal care.</p> <p>Methods</p> <p>As part of a larger prospective, cross-sectional study of pregnant women aged 16-25 years attending antenatal services across Melbourne, Australia, 100 women were invited to participate in a face-to-face, semi structured interview on the acceptability of screening for chlamydia during pregnancy. Women infected with chlamydia were oversampled (n = 31).</p> <p>Results</p> <p>Women had low levels of awareness of chlamydia before the test, retained relatively little knowledge after the test and commonly had misconceptions around chlamydia transmission, testing and sequelae. Women indicated a high level of acceptance and support for chlamydia screening, expressing their willingness to undertake whatever care was necessary to ensure the health of their baby. There was a strong preference for urine testing over other methods of specimen collection. Women questioned why testing was not already conducted alongside other antenatal STI screening tests, particularly in view of the risks chlamydia poses to the baby. Women who tested positive for chlamydia had mixed reactions, however, most felt relief and gratitude at having had chlamydia detected and reported high levels of partner support.</p> <p>Conclusions</p> <p>Chlamydia screening as part of routine antenatal care was considered highly acceptable among young pregnant women who recognized the benefits of screening and strongly supported its implementation as part of routine antenatal care. The acceptability of screening is important to the uptake of chlamydia screening in future antenatal screening strategies.</p