cssi/SciSciGPT-SciSciNet huggingface dataset:
Prosthetic Ring Choice in Secondary Mitral Regurgitation

Disappointing results seen with mitral valve replacement for functional regurgitation led surgeons to attempt valve repair to preserve left ventricular geometry. Secondary regurgitation is due to left ventricular pathology which often distorts the mitral annulus (Schmitto et al., Cardiol Rev 18(6):285–291, 2010). Bolling and colleagues first popularized mitral valve repair using an undersized mitral annuloplasty in the 1990s to address this pathology (Bach and Bolling, Am Heart J 129(6):1165–1170, 1995; Bolling et al., J Thorac Cardiovasc Surg 109(4):676–682, 1995; Bolling et al., J Thorac Cardiovasc Surg 115(2):381–386, 1998). Although Bolling’s initial cases were done using a down-sized flexible band, practically every other method of annuloplasty has been employed, ranging from suture methods, pericardium, flexible rings and bands, semirigid bands, complete symmetrical rings and specially shaped rings. Although, choice of ring has been historically driven by surgeon preference, critical examination of pathophysiological principles and clinical data allow formulation of certain concepts regarding optimal ring choice for treatment of secondary mitral valve regurgitation.
The Mutual Fund Investor

This chapter for an upcoming handbook on mutual funds (by Edward Elgar Publishing) offers an overview of the mutual fund market and the investors who inhabit it. On the supply side, mutual funds hold $16 trillion in financial assets and have become the largest component of our private retirement system. On the demand side, mutual fund ownership has become widespread, with 90 million fund-owning households composed mostly of middle-class, educated, and older investors.The portrait of mutual fund investors, painted by a large and consistent body of academic and government studies over the past few decades, is disturbing. Fund investors are mostly ignorant of fund characteristics, inattentive to risks (and opportunities) of different asset classes, and often insensitive to fund fees. Instead, fund investors tend to chase past returns and attempt to time the market. As a result, the average returns for fund investors (both in stock and bond funds) have significantly trailed benchmark market returns – according to some studies, by several percentage points.The role of financial intermediaries in the mutual fund market is also disconcerting. Often, financial advisers give fund investors conflicted advice, leading them to choose high-cost, under-performing funds on which the advisers garner commissions. Although some employers are shifting employees to low-cost, risk-appropriate balanced funds, many 401(k) plans remain less than optimal. Moreover, fund companies tout higher-cost actively managed funds, despite growing evidence that most, if not all, fund managers are unable to beat the market – particularly after fees.There are, however, glimmers of hope. Recently, many fund investors have moved to lower-cost index funds – reflecting a new sensitivity both to the importance of low costs and to the empty promise of active fund management. Target date funds have also established a beachhead in the 401(k) market. The recent clarion calls of the financial press reinforces these trends, as a growing drumbeat of stories emphasizes the importance of fund fees, the counter-productivity of trying to beat or time the market, and the emptiness of chasing past fund performance.
Acute Cardiac MRI Assessment of Radiofrequency Ablation Lesions for Pediatric Ventricular Arrhythmia: Feasibility and Clinical Correlation.

Background Arrhythmia ablation with current techniques is not universally successful. Inadequate ablation lesion formation may be responsible for some arrhythmia recurrences. Peri-procedural visualization of ablation lesions may identify inadequate lesions and gaps to guide further ablation and reduce risk of arrhythmia recurrence. Methods This feasibility study assessed acute post-procedure ablation lesions by MRI, and correlated these findings with clinical outcomes. Ten pediatric patients who underwent ventricular tachycardia ablation were transferred immediately post-ablation to a 1.5T MRI scanner and late gadolinium enhancement (LGE) imaging was performed to characterize ablation lesions. Immediate and mid-term arrhythmia recurrences were assessed. Results Patient characteristics include median age 14 years (1 - 18 years), median weight 52 kg (11 - 81kg), normal cardiac anatomy (n = 6), d-transposition of great arteries post arterial switch repair (n = 2), anomalous coronary artery origin post repair (n = 1), and cardiac rhabdomyoma (n = 1). All patients underwent radiofrequency catheter ablation of ventricular arrhythmia with acute procedural success. LGE was identified at the reported ablation site in 9/10 patients, all arrhythmia-free at median 7 months follow-up. LGE was not visible in 1 patient who had recurrence of frequent premature ventricular contractions within 2 hours, confirmed on Holter at 1 and 21 months post-procedure. Conclusions Ventricular ablation lesion visibility by MRI in the acute post-procedure setting is feasible. Lesions identifiable with MRI may correlate with clinical outcomes. Acute MRI identification of gaps or inadequate lesions may provide the unique temporal opportunity for additional ablation therapy to decrease arrhythmia recurrence. This article is protected by copyright. All rights reserved
Some Problems of Structural Optimization

Here we discuss global features of optimally assembled bodies and various formulations of optimization problems. So far, we have mainly discussed the best microstructures of composites. Now we comment on the optimal layout of these composites in an optimally designed body. According to our main concept, the optimal composites have a quasiperiodic structure that varies smoothly with the stress field (see, for example, (Armand et al., 1984)). In dealing with composites, we assume that the scale of the periodicity cells is so small that the external field can be treated as homogeneous, hence the composite is represented by its effective tensor. We keep this concept, but now we consider variation in the effective tensor.
(t,q)-Deformed Q-Systems, DAHA and Quantum Toroidal Algebras via Generalized Macdonald Operators

We introduce the natural (t, q)-deformation of the Q-system algebra in type A. The q-Whittaker limit $$t\rightarrow \infty $$ gives the quantum Q-system algebra of Di Francesco and Kedem (Lett Math Phys 107(2):301–341, [DFK17]), a deformation of the Groethendieck ring of finite dimensional Yangian modules, compatible with graded tensor products (Hatayama et al. in: Recent Developments in Quantum Affine Algebras and Related Topics (Raleigh, NC, 1998), Volume 248 of Contemporary Mathematics, Amer. Math. Soc., Providence, [HKO+99]; Feigin and Loktev in: Differential Topology, Infinite-Dimensional Lie Algebras, and Applications, Volume 194 of Amer. Math. Soc. Transl. Ser. 2, Amer. Math. Soc., Providence, [FL99]; Di Francesco and Kedem in Int Math Res Not IMRN 10:2593–2642, [DFK14]). We show that the (q, t)-deformed algebra is isomorphic to the spherical double affine Hecke algebra of type $${\mathfrak {gl}}_N$$ . Moreover, we describe the kernel of the surjective homomorphism from the quantum toroidal algebra (Miki in J Math Phys 48(12):123520, [Mik07]) and the elliptic Hall algebra (Schiffmann and Vasserot in Compos Math 147(1):188–234, [SV11]) to this new algebra. It is generated by (q, t)-determinants, new objects which are a deformation of the quantum determinant associated with the quantum Q-system. The functional representation of the algebra is generated by generalized Macdonald operators, obtained from the usual Macdonald operators by the $$SL_2({\mathbb {Z}})$$ -action on the spherical Double Affine Hecke Algebra. The generating function for generalized Macdonald operators acts by plethysms on the space of symmetric functions. We give the relation to the plethystic operators from Macdonald theory of Bergeron et al. (J Comb 7(4):671–714, [BGLX16]) in the limit $$N\rightarrow \infty $$ . Thus, the (q, t)-deformation of the Q-system cluster algebra leads directly to Macdonald theory.
Cardiovascular Complications Associated With Novel Cancer Immunotherapies

Immune therapies represent a quantum leap in the fight against cancer. Recently approved immune checkpoint inhibitors that target receptors involved in immune escape of cancer cells (including cytotoxic T lymphocyte-associated antigen-4 (CTLA-4), programmed cell death protein-1 (PD-1), and programmed cell death protein ligand-1 (PD-L1) are increasingly being used for therapeutic benefit in a number of cancers. The robust anti-cancer activity of these agents has been accompanied by the recognition of new adverse effects, often due to the over activation of immune system, that may limit their therapeutic benefit and adversely impact outcomes. Combination treatments in particular, such as approaches using two targeted immunotherapy agents, have higher risk of adverse effects. Our review focuses on the approved checkpoint inhibitor therapies and their potential for cardiovascular toxicity. While very few cases of autoimmune cardiotoxicity and myocarditis have been reported in clinical trials, severe, life-threatening episodes of heart failure and hemodynamic compromise associated with the use of immune checkpoint inhibitors have recently been reported in the literature. Early recognition, diagnosis, and management of autoimmune myocarditis represent an important clinical challenge with no current guidelines available for prevention, identification, and treatment of this serious condition. This area of cardio-oncology is evolving rapidly as more drugs in this class are being discovered and pending approval. There is a need for future studies focused on prospective identification of biomarkers and clinical standards for treatment and long-term follow-up of cardiovascular toxicity to successfully continue the treatment of cancer while preventing the adverse outcomes with novel immune therapies.
Causal Mediation Analysis Using R

Causal mediation analysis is widely used across many disciplines to investigate possible causal mechanisms. Such an analysis allows researchers to explore various causal pathways, going beyond the estimation of simple causal effects. Recently, Imai et al. (2008) [3] and Imai et al. (2009) [2] developed general algorithms to estimate causal mediation effects with the variety of data types that are often encountered in practice. The new algorithms can estimate causal mediation effects for linear and nonlinear relationships, with parametric and nonparametric models, with continuous and discrete mediators, and various types of outcome variables. In this paper, we show how to implement these algorithms in the statistical computing language R. Our easy-to-use software, mediation, takes advantage of the object-oriented programming nature of the R language and allows researchers to estimate causal mediation effects in a straightforward manner. Finally, mediation also implements sensitivity analyses which can be used to formally assess the robustness of findings to the potential violations of the key identifying assumption. After describing the basic structure of the software, we illustrate its use with several empirical examples.
Polka Heartland: Why The Midwest Loves to Polka

Review of: "Polka Heartland: Why The Midwest Loves to Polka," text by Rick March, pho-tos by Dick Blau
Energy technology and lifestyle: A case study of the University at Buffalo 2015 Solar Decathlon home

Abstract This paper reports the design process and measured performance of the University at Buffalo's net-zero energy prototype, the GRoW home, designed for the 2015 Solar Decathlon in Irvine, CA. Sustainable design intentions and pragmatic constraints are discussed in addition to the energy considerations for each design element. The GRoW home includes features designed to support a unique lifestyle, including an integrated greenhouse (the “GRoWlarium”) and various operable systems under the occupant's control. Whole-building energy simulations, spreadsheet calculations, daylighting simulations, and proprietary sizing software were used in design decision making. Energy performance predictions and measured results from the 2015 competition are discussed. The home was predicted to consume 177.11 kWh, and produce 238 kWh during the competition; it actually consumed 161 kWh, and produced 191 kWh, an error of 3% and 8%, respectively. The GRoW home ultimately had the lowest energy consumption of any SD 2015 house which successfully performed all competition-required tasks.
Jigsaw Method for Non-technical Skills in Cardiac Arrest: a Novel Application of This Active Learning Pedagogy

There has been increased recognition of the importance of non-technical skills (e.g., communication and leadership) for cardiac arrest management. However, training is often insufficient to cultivate the requisite level of proficiency of these non-technical skills. We evaluated non-technical and technical skills performance of internal medicine residents in simulated cardiac arrest cases prior to and following a novel application of an interactive teaching strategy known as the Jigsaw Method. This method is one of the several established teaching strategies intended to actively engage learners. Internal medicine residents participated in pre- and post-intervention medical knowledge quizzes and cardiac arrest simulation cases. Technical skills (i.e., medical knowledge) were assessed by multiple-choice quizzes and non-technical skills (i.e., leadership, communication) with performance scoring. Fifty-six residents, including 50 of 53 (94%) matriculated senior residents from within the internal medicine program, participated. There was statistically significant improvement in quiz scores (median 63.3 vs. 80.0, p < .0001) and mock code performance scores (median 58.4 vs. 72.1, p = 0.01), comprising both leadership and communication components. Application of the Jigsaw Method resulted in improved technical and non-technical cardiac arrest management skills. Our findings support the implementation of this active teaching-learning technique into graduate medical education (GME) for non-technical skills training.
Colour plasticity alters thermoregulatory behaviour in Battus philenor caterpillars by modifying the cue received

Behaviour is an important way for animals to rapidly respond to changes in their current environment; however, over extended periods animals can also respond to environmental change via slower, developmental plasticity in other traits. This developmental plasticity could itself alter the animal's behaviour in two ways: it could change the state of the aspect of the animal's current environment that induces the behaviour (the cue), or it could change the physiology underlying production of that behaviour (the behavioural reaction norm). We tested these alternatives for two responses to temperature, colour plasticity and refuge-seeking behaviour, in pipevine swallowtail, Battus philenor, caterpillars. Prior research found that black caterpillars seek thermal refuges at lower ambient temperatures than red caterpillars in the field. Here, we found that the effect of colour on behaviour in the laboratory depended on how we heated the caterpillars. When warmed by radiant heat, black caterpillars sought refuge sooner than red caterpillars, as occurs in nature. In contrast, when warmed by conduction of heat, black caterpillars no longer sought refuges sooner than red caterpillars. Both colour morphs began seeking refuges at the same body temperature in both experiments, and the sensitivity of their metabolic rate to temperature was also the same. Taken together, our findings indicate that while colour does change the cue for refuge seeking, it does not change the behaviour's reaction norm. Similar cue-mediated interactions may often occur for thermoregulatory behaviour in other species.
The relation of the road environment and bicycling attitudes to usual travel mode to school in teenagers

Abstract Although active travel to school for primary school students has been widely studied, research into the determinants of teenage active travel to school is noticeably lacking. Understanding the determinants of teen active travel to school is important given that teenage travel may have implications for the formation of habits that carry over to adulthood. We present evidence linking travel to school with bicycling attitudes and with road environments on plausible paths to school using data from a large cross-sectional survey of students at three high schools in Northern California. Results suggest that the relationship between attitudes and bicycling are stronger than the relationship between road environments and bicycling. Students’ perceived social pressure to bicycle has a particularly strong association with bicycling. Hypothetical intervention scenarios suggest that students would walk and bicycle to school at substantially greater rates if they had better road environments for walking and bicycling, shorter distances to school, and more positive bicycling attitudes.
Niche modeling for the genus Pogona (Squamata: Agamidae) in Australia: predicting past (late Quaternary) and future (2070) areas of suitable habitat.

Background As the climate warms, many species of reptiles are at risk of habitat loss and ultimately extinction. Locations of suitable habitat in the past, present, and future were modeled for several lizard species using MaxEnt, incorporating climatic variables related to temperature and precipitation. In this study, we predict where there is currently suitable habitat for the genus Pogona and potential shifts in habitat suitability in the past and future. Methods Georeferenced occurrence records were obtained from the Global Biodiversity Information Facility, climate variables (describing temperature and precipitation) were obtained from WorldClim, and a vegetation index was obtained from AVHRR satellite data. Matching climate variables were downloaded for three different past time periods (mid-Holocene, Last Glacial Maximum, and Last Interglacial) and two different future projections representative concentration pathways (RCPs 2.6 and 8.5). MaxEnt produced accuracy metrics, response curves, and probability surfaces. For each species, parameters were adjusted for the best possible output that was biologically informative. Results Model results predicted that in the past, there was little suitable habitat for P. henrylawsoni and P. microlepidota within the areas of their current range. Past areas of suitable habitat for P. barbata were predicted to be similar to the current prediction. Pogona minor and P. nullarbor were predicted to have had a more expansive range of suitable habitat in the past, which has reduced over time. P. vitticeps was predicted to have less suitable habitat in the past when examining the region of their known occurrence; however, there was predicted growth in suitable habitat in Western Australia. Both 2070 models predict a similar distribution of habitat; however, the model produced using the 2070 RCP 8.5 climate change projection showed a larger change, both in areas of suitable habitat gain and loss. In the future, P. henrylawsoni and P. microlepidota might gain suitable habitat, while the other four species could possibly suffer habitat loss. Discussion Based on the model results, P. henrylawsoni and P. microlepidota had minimal areas of suitable habitat during the Last Glacial Maximum, possibly due to changes in tolerance or data/model limitations, especially since genetic analyses for these species suggest a much earlier emergence. The predicted late Quaternary habitat results for all species of Pogona are conservative and should be compared to the fossil record which is not possible at the moment due to the current inability to identify fossil Pogona to the species level. P. nullarbor and P. vitticeps future models predict substantial habitat loss. P. nullarbor could potentially be considered vulnerable in the present since it already has a restricted range, and a conservation plan may need to be considered.
Intimate partner violence and academic performance: the role of physical, mental, behavioral, and financial health.

ABSTRACTUndergraduate students of all gender identities are at risk of experiencing intimate partner violence (IPV) victimization. It is known that IPV negatively affects academic performance, yet ...
Towards a Decolonial Theology: Perspectives from the Caribbean

This chapter develops the following topics: (1) The linkages between the Iberian conquest and Christianization of Latin America and the Caribbean, and the emergence of modernity, global empire, and capitalism. Latin America and the Caribbean became the cradle of modern expressions of Western imperial domination and missionary enterprises. It was an imperial process vindicated, but also contested, by theological arguments and scriptural hermeneutics, as attested by the writings of Francisco de Vitoria, Bartolome de Las Casas, Juan Gines de Sepulveda, Jose de Acosta, and others. (2) The ways in which contemporary biblical studies engage the voices of oppressed peoples and articulate decolonizing perspectives. Biblical Israel was a small nation subject to the ambitions of several powerful empires—Egypt, Syria, Assyria, Babylon, Macedonia, and Rome. Jesus’ crucifixion was a lethal expression of imperial repression in connivance with colonized hierarchies. (3) The emergence of contemporary decolonizing theologies, in conjunction with the Exodus paradigm and the hope for God’s kingdom that characterize Christian Scriptures. These theologies dare to discern critically the signs of times and radically engage the imperatives of human liberation.
Orientation and Spatial Frequency Selectivity: Properties and Modular Organization

There is by now overwhelming evidence that two of the primary characteristics of visual cells first seen at the striate level are those of orientation and spatial frequency selectivity (see De Valois & De Valois, 1988, for summary and discussion). Although lateral geniculate neurons show some minor degree of selectivity for both orientation and spatial frequency, they are rather broadly tuned along both parameters. Striate cortex neurons vary widely in their bandwidths along these dimensions, but on average they are much more narrowly tuned than geniculate cells. The average orientation bandwidth (full bandwidth at half amplitude response), in both cat and monkey striate cells, is about 45°, 1/4 of the total 180° range of possible orientations. The average spatial frequency bandwidths of cells are quite comparable: about 1.3 octaves, which is about 1/4 of the total ca. 5 octave range of spatial frequencies to which we are sensitive at a given eccentricity (De Valois, Hepler & Yund, 1982; De Valois, Albrecht & Thorell, 1982).
Combination of Simultaneous Artificial Sensory Percepts to Identify Prosthetic Hand Postures: A Case Study.

Multiple sources of sensory information are combined to develop hand posture percepts in the intact system, but the combination of multiple artificial somatosensory percepts by human prosthesis users has not been studied. Here, we report on a case study in which a person with transradial amputation identified prosthetic hand postures using artificial somatosensory feedback. He successfully combined five artificial somatosensory percepts to achieve above-chance performance of 95.0% and 75.7% in identifying four and seven postures, respectively. We studied how artificial somatosensation and the extant hand representation are combined in the decision-making process by providing two mappings between the prosthetic sensor and the location of the sensory percept: (1) congruent, and (2) incongruent. The participant’s ability to combine and engage with the sensory feedback significantly differed between the two conditions. The participant was only able to successfully generalize prior knowledge to novel postures in the congruent mapping. Further, he learned postures more accurately and quickly in the congruent mapping. Finally, he developed an understanding of the relationships between postures in the congruent mapping instead of simply memorizing each individual posture. These experimental results are corroborated by a Bayesian decision-making model which tracked the participant’s learning.
A New Rhynchosaur (Reptilia, Archosauromorpha) from the Upper Triassic of Eastern North America

This paper provides a description and analysis of cranial remains of a rhynchosaur from the Upper Triassic Evangeline Member of the Wolfville Formation of Nova Scotia, Canada. This material, primar...
Does finding a face cell tell us anything much at all

There are two approaches to doing science. One is the “tractor” approach. You take a big, powerful piece of machinery and apply it in systematic fashion to a problem. Here, “you” is often a large group of people who share the same goal. A recent example is the International Brain Lab (Abbott et al., 2017), a consortium of labs across the world all performing the same experiment to understand visually-guided decision making in the rodent. The plan is for each lab to repeat the behavioral experiment while inserting advanced high channel count electrodes into different parts of the brain, like a fleet of tractors mowing a field. A very different, older approach is that of the lone hunter pursuing a question no one else cares about, guided by a vision in his or her own head. Auden captures the essence of this approach in his wonderful poem “History of Science.” The poem tells the tale of the Fourth Brother, who has been excised from the official fairy tale...
Time Travel: A Live Demo of the Intermedia Hypertext System - Circa 1989

In the late 1980s, before the WWW came to be, hypertext was a hot new field. Brown University's Institute for Information and Scholarship (IRIS) developed Intermedia, a networked, multiuser, multi application hypermedia system that was well-known and oft demoed at conferences (and used by the speaker for his keynote at Hypertext '89). Its most lasting contribution has been the speaker's coining of the word "anchor" to represent the "sticky selection" that is the source or destination of a link within documents. Anchors generalized these link endpoints to include any media type.Intermedia's development began in 1985. Its paradigm was the integration of bi-directional hypermedia links between different applications in what was then the graphical desktop interface introduced by Apple only a year earlier.Intermedia had many features, some of which have since become mainstream -- anchors (links to a span of text or a set of objects, rather than just a point), full-text indexing, dictionary lookup, links in different media type -- and some still yet to be common in web browser-based systems-- such as bi-directional links, integrated annotation capabilities, tracking of anchors in edited documents, and simultaneous linking by multiple individuals across the network.Two years ago, the Computer History Museum asked if the speaker could resurrect Intermedia to show at the celebration of the 50th Anniversary of the Doug Engelbart's Mother-of-All-Demos. It was believed that all of the backup disks and tapes had deteriorated, but through the intervention of the hypertext gods, a disk was found that worked and had a full-installation of Intermedia, along with demo files -- including the Hypertext '89 keynote content.The speaker procured some Macintosh IIci machines, monitors, mice, and keyboards on eBay and amazingly, Intermedia ran.In this presentation, you will see a fully-operational hypermedia system running quite nicely on a computer that is 250,000 times slower than today's high-end PCs.
Diabetes and obesity are associated with disability in community-dwelling stroke survivors: A cross-sectional study of 37,955 Behavioral Risk Factor Surveillance System respondents.

Purpose. Stroke increases risk for disability. Obesity and diabetes also increase risk for disability in the general population, but their association with disability in stroke survivors is unknown. We examined disability risk associated with obesity and diabetes in stroke survivors across six disability types: hearing, vision, cognition, mobility, and basic and instrumental activities of daily living (ADLs).Materials and Methods. Data from 37,955 community-dwelling US stroke survivors aged ≥18 years were analyzed from the 2017 and 2018 Behavioral Risk Factor Surveillance System. Linear regression was used to calculate prevalence of each disability type. Survivors were stratified by obesity versus normal weight and diabetes vs no diabetes, and logistic regression was used to calculate adjusted odds ratios (AOR) for each disability type, adjusted for demographic information.Results. Prevalences of disability types ranged from 14.2% to 36.0%. Among survivors with obesity, odds were elevated for mobility (AOR: 1.68) and basic ADL (AOR: 1.55) disability. Among survivors with diabetes, odds were elevated for all disability types (AOR range: 1.15-1.71).Conclusion. Stroke survivors with obesity or diabetes experience increased risk for disability compared to survivors without these chronic conditions. Interventions for managing disability, obesity, and diabetes concomitantly may be warranted and deserve further consideration.
Medical Service Quality and Office Rent Premiums: Reputation Spillovers

Location spillovers are a common theme in real estate and urban economics research, but this is the first test on the relationship between hospital service quality and the demand for proximate medical office space. We hypothesize that hospitals with reputations for high quality service represent an opportunity for physicians, and other service providers, to benefit from reputation spillovers. Further, the reputation benefit is capitalized into the practices’ willingness to pay for proximate office locations, thereby driving up the rental rates for nearby space. We find that distance from, and overall quality ranking of the hospital, both independent and in concert, are significantly linked to the base rents. The degradation in rent with distance is significantly greater when the hospital is ranked high in overall service quality, supporting the notion that a rent premium is linked to the high-quality hospital rather than simply an artifact of the neighborhood.
Pandemic Responses of Churches in Southern Vermont and the Surrounding Area

Article presents the results of a survey given to churches in and around southern Vermont regarding their responses to the coronavirus disease-2019 pandemic of 2020/2021. The article also presents the reported lessons learned and implications for future ministry from the responding churches with analysis of what those thoughts mean for the church of the future in New England and beyond.
Chapter 2 High-Efficiency AlGalnP Light-Emitting Diodes

Publisher Summary This chapter focuses on the development and performance of aluminum gallium indium phosphide (AlGaInP) light-emitting diodes (LEDs). The AlGaInP quaternary alloy system is widely used for visible wavelength optical devices such as lasers and light-emitting diodes (LEDs). AlGaAs direct bandgap red LEDs, first as absorbing substrate (AS) devices and later as transparent substrate (TS) devices, grown by liquid phase epitaxy (LPE) resulted in improved efficiencies of ∼10 lm/W (∼14% radiant efficiency). These were the first LED devices to take advantage of the efficient double heterostructure (DH) design and made outdoor applications such as red traffic-signal lights and automobile brake lighting a possibility. AlGaInP is an important optoelectronic material for LED and visible laser diode applications. Recent advances in GaN technology have provided efficient blue and green emitters, which make full color displays possible.
Fitting additive models to regression data: diagnostics and alternative views

Abstract A method is given for fitting additive models to multivariate regression type data. The emphasis is on diagnostics analogous to the concept of influence and on alternative models. These are illustrated in three case studies. Simulations show excellent predictive accuracy as compared with existing methods.
On the Robust Single Machine Scheduling Problem

The single machine scheduling problem with sum of completion times criterion (SS) can be solved easily by the Shortest Processing Time (SPT) rule. In the case of significant uncertainty of the processing times, a robustness approach is appropriate. In this paper, we show that the robust version of the (SS) problem is NP-complete even for very restricted cases. We present an algorithm for finding optimal solutions for the robust (SS) problem using dynamic programming. We also provide two polynomial time heuristics and demonstrate their effectiveness.
Autism, Rhetoric, and Whiteness

Keywords: autism, rhetoric, whiteness This paper first explicates various forces working to construct autism as an overwhelmingly white phenomenon in public discourse, including popular films, television programming, "armchair" internet diagnoses, "geek chic," "shiny" autistics, "Aspie supremacy," the rhetorics of autism advocacy organizations, special education, access to health care, and parental education levels. It then considers the epistemological and rhetorical implications of autistic whiteness, including an examination of its functions in Burkean identification and its possible operation in educational, workplace, criminal justice, and governmental contexts.
Does human maternal behaviour after delivery show a characteristic pattern

Specific kinds of maternal behaviour such as nesting, retrieving, grooming and exploring, are seen in non-human mammalian mothers immediately before, during and after delivery. In this study 22 human mothers were filmed during the first 10 minutes of contact with their normal nude full-term infants, who were placed beside them in private rooms in hospitals in Guatemala and the US; and nine mothers of premature infants were filmed on their first three visits to the nursery. Another 10 Guatemalan mothers and infants were observed for 10 minutes almost immediately after delivery in hospital. These observations were compared to maternal behaviour after home deliveries in California. After hospital delivery all US mothers, but only half of the Guatemalans, began touching their infants' extremities with their fingertips and proceeded within a few minutes to palm contact on the trunk. US mothers had an intense interest in eye-to-eye contact. Mothers of premature infants showed only fragments of this behaviour. In home births when the mothers are active participants in delivery, they pick up the infant immediately after birth, stroke its face with their fingertips and start breast-feeding within the first minutes after delivery. Initially the infant only licks the nipples. there is striking elevation in mood in the parents. These observations focus attention on reciprocal behaviour patterns that develop early between mother and infant and which serve to unite them.
Reliability of Low Cost Cu2S/CdS Solar Cells for Large Scale Conversion of Solar to Electrical Energy

Large scale conversion of solar to electrical energy at low cost is possible using high efficiency, high reliability Cu2S/Cds solar cells. Low cost fabrication involves relatively simple processes consuming small amounts of material. Accelerated life tests give extrapolated lifetime in excess of twenty years. The probable decay mechanisms are thermal diffusion, formation of recombination centers, and voltage induced decomposition.
Determination of Cholinesterase in Blood and Tissue

The widespread use of organophosphate and organocarbamate pesticides and the dangers of related chemical warfare agents dramatize the importance of rapid, accurate, and sensitive assays for blood and tissue cholinesterases (ChEs), important targets for neurotoxic chemicals. Two ChE enzymes used as biomarkers of exposure are the specific acetylcholinesterases (AChE, EC 3.1.1.7) and the nonspecific plasma cholinesterases (BChE, EC 3.1.1.8). This unit contains two protocols for measuring ChE activity: (1) a colorimetric kinetic method and (2) a radiometric endpoint assay and selective inhibitors that are used to distinguish between the two classes of enzymes.
On sums of powers in Ramanujan's lost notebook

On one page in his lost notebook, Ramanujan records seven formulas for sums of powers. The meaning of these formulas is not clear. We provide a proper interpretation and indicate their connection with maximum and minimum values of Bernoulli polynomials.
Social ties, task-related communication and first job performance of young engineers

Abstract This study investigated the relationships among social ties, task-related communication, and first industrial job performance of a group of young engineers by utilizing a cooperative (coop) engineering program as a natural study. The coop arrangement allowed the researcher to examine the work behavior of these young engineers with similar academic training who were working on comparable work assignments in the same set of organizations. The study found that the job performance of the coop engineers was related to the pattern of work- related communication but not the total number of contacts. Specifically, high performance new engineers were integrated more broadly into the interpersonal communication networks than low performance new engineers. Moreover, high performance new engineers exhibited communication patterns similar to those of high performance veteran engineers working on similar types of technical work. Social ties with the company staff was found to be related positively with job performance, but social ties with other coop engineers was found to be related negatively with job performance, a result which challenges an implicit assumption often made by researchers and managers about the organizational socialization of newcomers. Overall, this study provides an integrative framework for relating social ties and communication as key factors for understanding the job performance of young engineers and presents a methodology for assessing their organizational assimilation.
Total Knee Arthroplasty After Lower Extremity Amputation: A Review of 13 Cases

Below knee amputation protects the ipsilateral knee from osteoarthritis and overloads the contralateral knee predisposing it to symptomatic osteoarthritis. We retrospectively reviewed 13 primary total knee arthroplasty (TKAs) in 12 patients with a prior lower extremity amputation. Twelve TKAs were performed on the contralateral side of the amputated limb while only one TKA was performed on the ipsilateral side. The average clinical follow-up was 6.8 ± 4.8 years. Knee Society Scores improved from 30.4 ± 11.8 to 88.5 ± 4.2 after TKA with a prior contralateral amputation. Three (23.1%) patients with TKA after contralateral amputation had aseptic loosening of the tibial component. Patients experience clinically significant improvement with TKA after lower extremity amputation. Augmentation of tibial fixation with a stem may be advisable during TKA after contralateral amputation.
Molecular adsorption: repulsive versus attractive supercritical fluid mixtures

Abstract The behavior and structure of supercritical fluid (SCF) mixtures in contact with an adsorptive solid surface have been determined by the nonuniform Ornstein–Zernike integral equations for the molecular distributions. In this work, we examine the behavior of attractive and repulsive mixtures (A=SCF and B=solute) with respect to adsorption on planar substrates. Properties and fluid structures in the vicinity of the wall (W) are explored. The behavior of a dilute solute B adsorbed to wall W from solvent A (i.e. system A+B/W) is described for the cases where A+B form either an attractive SCF mixture or a repulsive SCF mixture for a temperature where the solvent A is slightly supercritical and for density conditions where A is subcritical, critical, and supercritical. We examine the degree of preferential adsorption of B vis-a-vis the competitive interactions with A and W. This shows the relative adsorptions, while covering a range of states. We find evidence of solute rejection by the SCF toward the wall, when the mixture A+B changes character from `attractive' to `repulsive'. The numerical work is very demanding in computer memory and time. Thus, full numerical convergence has not been achieved in the calculations reported here. We have attained partial convergence. However, the qualitative trends are considered unaltered. The mechanisms of solute adsorption in SCF have been demonstrated at a fundamental molecular level.
An affine transformation description of epitaxial heterostructures

The matching at the interface between the substrate and the film in an epitaxial deposit has been analyzed and explained very well in the literature for the various fcc-bcc metallic systems by the use of the energy minimization criteria such as invariant line criterion, the O-lattice approach etc. Though many orientation relationships have been reported for other crystal structures and non-metals, very little effort has been made to explain these relationships. Here, we attempt to rationalize the orientation relationships that we have obtained and which others have reported for epitaxial suicides using the above mentioned criteria.
Operating performance following dividend decreases and omissions

Abstract Using quarterly data and benchmarks based on past performance characteristics, I find little evidence that earnings change following 661 dividend decreases and 484 dividend omissions between 1980 and 1998. The exception is that earnings deteriorate during the quarter of dividend omissions, but they recover within a couple of quarters. My results further suggest that the lack of a more pronounced earnings decline is neither attributable to a contemporaneous and confounding increase in share repurchases, to earnings management, nor to improving investment opportunities, and the results are similar for firms that are not predicted to cut dividend payouts based on their financial flexibility. Instead, I find some evidence that the negative stock price reaction reflects the dismal performance during the quarter of the announcement, especially for firms that omit dividends, and that the market interprets the dividend announcements too pessimistically.
Temperature dependence of water content and proton conductivity in polyperfluorosulfonic acid membranes

Abstract The Fourier transform infrared (FTIR) spectra and the proton conductivity were determined in the temperature range of 25°C to 100°C, while in contact with a water-saturated nitrogen atmosphere. The water content of the membrane was not continuously proportional to the mole fraction of water in the vapor phase but reached a minimum near 70°C. The proton conductivity was found to maximize between 55 and 65°C. These results indicated that membrane water content is not as important as temperature in determining membrane conductivity. At temperatures below 55°C, the conductivity increased with temperature, despite a decrease in membrane water content. In this temperature domain membrane water played a less significant role in determining the conductivity than the effect of temperature in overcoming the 3 to 5 kcal/mol activation energy for proton movement. Above 70°C the conductivity decreased, while the membrane water content increased. The infrared results showed an increase in the number of un-ionized sulfonic acid groups at higher temperatures. The decrease in conductivity was attributed to this increase in the quantity of sulfonic acid groups that were not ionized. These results are explained using current models of cluster formation. Cluster formation is favored by the sulfonic acid/water dipole interactions but is hindered by extension of the polymer side chains as the sulfonic acid groups aggregate. The side chain configuration contributes to the entropy term for the free energy of cluster formation. Hence clusters will become less stable at higher temperatures and some sulfonic acid groups withdraw from the clusters into the nonpolar fluorocarbon region.
The nest architecture of the Florida harvester ant, Pogonomyrmex badius

Abstract The architecture of the subterranean nests of the Florida harvester ant, Pogonomyrmex badius, was studied through excavation and casting. Nests are composed of two basic units: descending shafts and horizontal chambers. Shafts form helices with diameters of 4 to 6 cm, and descend at an angle of about 15–20° near the surface, increasing to about 70° below about 50 cm in depth. Superficial chambers (< 15 cm deep) appear to be modified shafts with low angles of descent, and are distinct from deeper chambers. In larger nests, they have a looping, connected morphology. Chambers begin on the outside of the helix as horizontal-floored, circular indentations, becoming multi-lobed as they are enlarged. Chamber height is about 1 cm, and does not change with area. Chamber area is greatest in the upper reaches of the nest, and decreases with depth. Vertical spacing between chambers is least in the upper reaches and increases to a maximum at about 70 to 80% of the maximum depth of the nest. The distribution o...
New risk rates, inter-industry differentials and the magnitude of VSL estimates

The Census of Fatal Occupational Injury (CFOI) provides data for creating objective measures of workplace risk used in estimations of wage-risk premia for Value of Statistical Life (VSL) calculations. This relatively new data set enables a more theoretically defensible measure for use in hedonic wage equations. However, constructing these rates from the CFOI data necessarily involves creating an industry-occupation matrix defining the 'jobs', deciding whether or not to include the self-employed, and selecting a denominator. These choices in the construction of the risk measure alone, as shown here, result in variations of VSL estimates ranging from $8 million to $18 million. Further, risk measures based on the CFOI data, regardless of construction, are sensitive to simple changes in the specification for the hedonic wage equation. In particular, fixed effects describing the industry in which a worker is employed, as well as the worker's occupation, are primary influences on the magnitude of the VSL estimates. This research was conducted with restricted access to Bureau of Labor Statistics (BLS) data. The views expressed here do not necessarily reflect the views of the BLS. Click here for brief description of the fatal workplace risk rates created Click here for a summary of the risk measures and details on the two job cluster matrices Click here for descriptive Stats on Labor Force sample
Enhanced base-to-user satellite Gain Variation Reduction algorithm for MUOS

Based on Universal Mobile Telecommunications System (UMTS) Wideband Code Division Multiple Access (WCDMA) technology, the Mobile User Objective System (MUOS) provides a wide range of wireless telecommunications services to the war fighter over geosynchronous satellites. As MUOS is a multiple beam system, it is of paramount importance for the User Entry (UE) to select the best beam, which in turn requires accurate transmit power from the satellite. To minimize the satellite path gain uncertainty from the base station to the UE, the Enhanced Gain Variation Reduction (EGVR) algorithm is proposed. Implemented on the basis of the measurements of the received signal code power (RSCP) of the pilot channel from the UE and the measurements of the received signal code power at the terrestrial base station, the EGVR process generates the transmission power estimate and integrates it into the overall gain adjust system to keep the transmission power levels as desired. The features of the algorithm include the weighted gain adjusts generated from the estimation error, appropriate timers to control the measurement flow, and differential measurements to eliminate the common errors between satellite beams. The preliminary study shows that the EGVR can reduce the power uncertainty from 2.4 dB to 0.4 dB, in addition to reducing any differential errors encountered. With the blending of the telemetry feedback into the algorithm, it can make the transmit power uncertainty even smaller.