1,141 research outputs found
Environmental variables affect fungal diversity on blueberry (Vaccinium spp.) leaf surfaces:
No full textThe economically important blueberry, Vaccinium cyanococcus, is susceptible to a number of diseases, some of which are propagated by fungi living on the leaf surface. The leaf surface (phylloplane) is a cryptic environment that harbors a variety of pathogens and pathogen antagonists, and these populations are affected by many factors including weather, season, host plant location and leaf phenology. Blueberry leaves were collected in April, June, August, and October over two years from bushes in wild areas and cultivated farms along transects perpendicular to the Atlantic City Expressway, to address the hypothesis that pollution from a major highway would influence phylloplane communities. Leaves were washed and plated on potato dextrose agar, and fungal epiphytes were identified using taxonomic keys and microscopy. Epicoccum spp., Alternaria spp., Pennicilium spp., and Curvularia spp. were the most ubiquitous fungi isolated from blueberry leaves. Community structure and species richness changed from site-to-site and month-to-month and from year-to-year. The influence of highway proximity to fungal communities was not significant. Management practices in cultivated sites accounted for much of the variation in species richness and community composition among sites. Leaf age also influenced the community structure of phylloplane fungi communities. Leaves collected in April had significantly lower species richness than those collect in later months (F=19.37, P<0.0001). Yearly differences in species richness and community structure were likely due to differences in meteorological variables. Greater information provided by frequency of occurrence of fungal species would lead to a more informative multivariate analysis as presence or absence would be weighted by abundance, allowing for interpretations of dominance and more detailed analysis of phylloplane fungal communities.M.S.Includes bibliographical references (p. 25-27)by Jason Stanwoo
Multi-attribute tradespace exploration and its application to evolutionary acquisition
No full textThesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2003.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Includes bibliographical references (p. 144).by Jason Edward Derleth.S.M
The number of degree sequences of graphs
No full textThesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mathematics, 2007.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Includes bibliographical references (leaves 60-62).We give nontrivial upper and lower bounds for the total number of distinct degree sequences among all simple, unlabeled graphs on n vertices (graphical partitions on n vertices). Our upper bound is ... for some constant C, and improvement of ... over the trivial upper bound which is asymptotic to ... Our lower bound is ..., and improvement of ... over the trivial lower bound which is asymptotic to ...by Jason Matthew Burns.Ph.D
Four days of blueberry powder supplementation lowers the blood lactate response to running but has no effect on time-trial
No full textBlueberries are abundant with anthocyanins possessing antioxidant and anti-inflammatory properties. As these properties combat fatigue and promote recovery, blueberry supplementation may enhance performance and recovery. Thus, the objectives were to examine the effects of two blueberry supplementation protocols on running performance, physiological responses, and shortterm recovery. Using a randomized, double-blind, placebo (PLA)-controlled crossover design, 14 runners completed an 8-km time trial (TT) after supplementation with 4 days of blueberries (4DAY), 4 days of a PLA, or 2 days of placebo followed by 2 days of blueberries (2DAY). Heart rate and ratings of perceived exertion were monitored during the TT. Blood lactate, vertical jump, reactive strength index, and salivary markers were assessed before and after. No significant differences were observed for time to complete the TT (PLA: 3,010 ± 459 s; 2DAY: 3,014 ± 488 s; 4DAY: 3,011 ± 423 s), heart rate, ratings of perceived exertion, or any of the salivary markers. An interaction effect (p = .027) was observed for blood lactate, with lower post-TT concentrations in 4DAY (5.4 ± 2.0 mmol/L) than PLA (6.6 ± 2.5 mmol/L; p = .038) and 2DAY (7.4 ± 3.4 mmol/L; p = .034). Post-TT decreases in vertical jump height were not different, whereas the decline in reactive strength index was less following 4DAY (-6.1% ± 13.5%) than the other conditions (PLA: -12.6% ± 10.1%; 2DAY: -11.6% ± 11.5%; p = .038). Two days of supplementation did not influence performance or physiological stress. Although 4 days of supplementation did not alter performance, it blunted the increase in blood lactate, perhaps reflecting altered lactate production and/or clearance, and offset the decrease in dynamic muscle function post-TT, as indicated by the reactive strength index differences. [ABSTRACT FROM AUTHOR]Peer reviewedFinal article published.time trialpolyphenolexercise performanceanthocyani
Book Review: The Military Legacy of Alexander the Great: Lessons for the Information Age
No full textAuthor: Michael P. Ferguson and Ian Worthington
Reviewed by Jason W. Warren, PhD
The Military Legacy of Alexander the Great: Lessons for the Information Age focuses on three themes—inspirational physical presence, Alexander’s army’s professionalism, and the speed with which he campaigned. The reviewer notes there are many useful observations, overall, he sees the book as a “mixed bag.” For those newer to studies “on Alexander or lessons-learned methodology, Legacy may prove a useful primer.”https://press.armywarcollege.edu/parameters_bookshelf/1091/thumbnail.jp
Canine immune-mediated polyarthritis: clinical and laboratory findings in 83 cases in western Canada (1991-2001).
No full textA hospital-based, case-control study was used to describe clinical and laboratory findings in 83 dogs diagnosed with noninfectious, nonerosive, immune-mediated polyarthritis (IMPA) in western Canada. Case medical records were reviewed. Cases were analyzed as total IMPA cases and as subgroups [breed, systemic lupus erythematosus (SLE), reactive, and idiopathic] and compared with the general canine hospital population. Dogs with IMPA differed in age (P = 0.004) and weight (P = 0.01) from other hospital admissions. Idiopathic IMPA cases were older (4-10 y; P < 0.05), compared with the general canine hospital population, and their common laboratory abnormalities included the following: leukocytosis, nonregenerative anemia, increased alkaline phosphatase, and hypoalbuminemia. The SLE cases were seen more often in summer and fall (P = 0.04), raising concern of an undiagnosed etiologic agent. The hock joint appeared to be the most reliable for diagnosis of IMPA, and arthrocentesis of both hock joints may aid in case identification.journal article2008 Decimporte
Applying linguistics in the conservation of the social and cultural context of underdocumented languages
No full textTo describe the grammar of a language is a difficult task. It requires specialized training in several formal subfields of linguistics. The type of resulting documents on specific languages are valuable for a number of reasons. For example, they are often used in language conservation to build teaching materials for a language, and can facilitate research into the social and cultural context of the language. Within the field of language documentation, the roles of producing language pedagogy materials and describing language in its social and cultural context have been recognized (Franchetto 2006, Hill 2006), but, the goal of fields like linguistic anthropology and sociolinguistics, that is, to understand the internal dynamics of social organization, hence to some degree applied linguistics also, is missed by the bulk of grammatical description and language documentation due to the tacit and widespread assumption that language is componential. Indeed language can be seen as componential, but this view is inherently too limited to be reconciled with understanding language as culture. Therefore, the primary challenge is to integrate the available methods and techniques from the relevant fields to unveil and portray linguistic phenomena accurately in the practice of describing a language as a socioculturally embedded phenomenon and to make those materials relevant to teaching the language.
The research presented in the four sections of this talk compare the componential grammar model (e.g., Author 2014, Thieberger 200X) and the ethnography of communication/interactional model (Duranti 2009) and how they pair up with traditional language pedagogy (Kramsch 2002) and ethnologically informed modes of transmitting knowledge (Philips 1970, Wilson 2012), in an effort to identify specific ways to combine the best of the available models. Section 1 reviews the pros and cons of the traditional descriptive approach and the socio-culturally informed approach. Section 2 outlines the crucial role of social and cultural relevance in, not only, how languages are taught and maintained, but also what material constitutes the curriculum. Section 3 examines the nearly inevitable role of multi-lingualism in language conservation. Section 4 makes recommendations about how to expand the theoretical and analytic horizons of language documentation and applied linguistics to center on a view of language that is more than grammar and an interest in speakers as merely organisms that produce linguistic forms.
References:
Author. 2014. A Grammar of X.
Duranti, Alessandro (ed.). 2009. Linguistic Anthropology: A Reader. Second edition. Hoboken, New Jersey: Wiley-Blackwell.
Franchetto, Bruna. 2006. Ethnography in language documentation. In Jost Gippert, Nikolaus P. Himmelmann, and Ulrike Mosel Essentials of Language Documentation, 113–128. Berlin: Mouton de Gruyter.
Hill, Jane. 2006. The ethnography of language and language documentation. In Jost Gippert, Nikolaus P. Himmelmann, and Ulrike Mosel Essentials of Language Documentation, 183–212. Berlin: Mouton de Gruyter.
Kramsch, Claire (ed.). 2002. Language Acquisition and Language Socialization: Ecological Perspectives. New York: Continuum.
Philips, Susan U. 1970. Participant structures and Communicative Competence: Warm
Springs Children in Community and Classroom. In J. E. Alatis (ed.) Bilingualism and Language Contact: Anthropological, Linguistics, Psychological and Social Aspects _ Acquisition of Rules for Appropriate Speech Usage. Washington D.C.: Georgetown University Press.
Thieberger, Nicholas. 2004. Topics in the grammar and documentation of South Efate, an Oceanic language of Central Vanuatu. PhD diss., Melbourne: Department of Linguistics and Applied Linguistics, University of Melbourne.
Wilson, William H. 2012. Hawaiian language revitalization. In Language in Hawai‘i
and the Pacific. University of Hawai‘i at Mānoa Linguistics 100 Course Reader, ed. by Hiroko Sato and Jake Terrell, 118–29. Honolulu: University of Hawai‘i
Rescue of Metabolic Alterations in AR113Q Skeletal Muscle by Peripheral Androgen Receptor Gene Silencing
No full textSummarySpinal and bulbar muscular atrophy (SBMA), a progressive degenerative disorder, is caused by a CAG/glutamine expansion in the androgen receptor (polyQ AR). Recent studies demonstrate that skeletal muscle is an important site of toxicity that contributes to the SBMA phenotype. Here, we sought to identify critical pathways altered in muscle that underlie disease manifestations in AR113Q mice. This led to the unanticipated identification of gene expression changes affecting regulators of carbohydrate metabolism, similar to those triggered by denervation. AR113Q muscle exhibits diminished glycolysis, altered mitochondria, and an impaired response to exercise. Strikingly, the expression of genes regulating muscle energy metabolism is rescued following peripheral polyQ AR gene silencing by antisense oligonucleotides (ASO), a therapeutic strategy that alleviates disease. Our data establish the occurrence of a metabolic imbalance in SBMA muscle triggered by peripheral expression of the polyQ AR and indicate that alterations in energy utilization contribute to non-neuronal disease manifestations
Axiomatic system design : chemical mechanical polishing machine case study
No full textThesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2003.Includes bibliographical references (p. 205-209).This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Axiomatic design is investigated as a design methodology for large or complex system design. Particular considerations of system design are described and the suitability of axiomatic design for such considerations is discussed. Then, tools to enable successful application of axiomatic design to systems are developed. The tools are expressed as theorems for axiomatic system design. The first theorem describes conditions for equivalence of FRs, and helps define the relationships within a design matrix. The second theorem describes a method of using only leaf levels to represent a system, and re-sequencing the design to achieve a decoupled matrix. Therefore, some types of coupling at high levels may be reduced or eliminated. The third theorem defines the decomposition strategy that is necessary to make axiomatic design compatible with object-oriented simulation models that are created starting with the high levels of the decomposition. The fourth and fifth theorems present a new method for considering and increasing system robustness to external noise factors during the conceptual design phase. While techniques for increasing robustness to external noise factors are known, integrating them into axiomatic design has not been shown previously. A case study of the design of a machine tool system for polishing silicon wafers using chemical mechanical polishing (CMP) is presented. The CMP system architecture is decomposed from top level requirements using the principles of axiomatic design, and the theorems developed in this thesis. The CMP system was designed and fabricated at MIT by a team of students, and has demonstrated excellent capability to remove material from the surface of a wafer while offering increased control of the removal profile.by Jason W. Melvin.Ph.D
Physiological responses to diesel exhaust exposure are modified by cycling intensity
No full textBackground
Outdoor exercisers are frequently exposed to diesel exhaust (DE) that contains particulate matter (PM) air pollution. How the respiratory and metabolic responses to exercise are affected by DE exposure and how these responses change with exercise intensity are unknown.
Purpose
This study aimed to determine the respiratory and metabolic responses to low- and high-intensity cycling with DE exposure containing high levels of PM.
Methods
Eighteen males age 24.5 ± 6.2 yr performed 30-min trials of low-intensity (30% of power at V˙O2peak) and high-intensity (60% of power at V˙O2peak) cycling as well as rest. Each trial was performed once while breathing filtered air (FA) and once while breathing DE (300 μg·m−3 of PM2.5) for a total of six trials, each separated by 7 d. During the trials, minute ventilation (V˙E), oxygen consumption (V˙O2), CO2 production (V˙CO2), RER, and perceived exertion for lungs (RPELungs) and legs (RPELegs) were measured. Work of breathing, respiratory muscle V˙O2, ratio of O2 consumption to power output, and gross efficiency were estimated.
Results
The RER was significantly lower (0.02 lower, P = 0.008), and the RPELungs (0.9 greater, P = 0.001) and the RPELegs (0.6 greater, P = 0.017) were significantly greater, in DE compared with FA. During low-intensity exercise, V˙E (44.5 ± 8.9 vs 40.5 ± 8.0 L·min−1, P < 0.001), V˙O2 (27.9 ± 5.4 vs 24.9 ± 4.4 mL·kg−1·min−1, P = 0.001), and V˙CO2 (25.9 ± 5.3 vs 23.5 ± 4.5 mL·kg−1·min−1, P = 0.006) were significantly greater in DE. This pattern was not seen during high-intensity cycling.
Conclusions
Respiratory and metabolic responses to low-intensity, but not high-intensity, cycling in DE exceed FA. Practically, the greater responses during low-intensity exercise in DE could have implications for individuals with cardiopulmonary disease. Also, the elevated RPE during DE could impair performance in self-paced exercise.Peer reviewedFinal article publishedRespiratory metabolicAir pollutionExerciseParticular matte
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