485 research outputs found
The Phytogeographical Significance of Some Rare Plants at Back Bay
The Back Bay region has long been recognized for its many species which reach either their northern or southern limits there. The eminent Harvard botanist M.L. Fernald collected extensively in the Back Bay region during the late 1930\u27s and early 1940\u27s. He postulated the Back Bay area provided a unique opportunity for the migration of fresh and brackish water species through a series of interconnected or neighboring marshes and pools. His collections document the presence of several species which we now consider extirpated.
Of especial interest are genera with vicarious species pairs, that is, one area of overlap between wide-ranging species and southern species is at Back Bay. We present information on two such pairs: Lilaeopsis carolinensisand Lilaeopsis chinensis (wide-ranging); and Lippia nodiflora (southern) and Lippia lanceolata (wide-ranging). In addition we discuss species which reach their northern or southern limits at Back Bay. Examples include: Limosella subulata (Scrophulariaceae), a northern species which apparently has been extirpated, and Juncus megacephalus (Juncaceae), an endemic of the southeastern United States which is abundant near its northern limit at Back Bay
Adaptive GDSW coarse spaces of reduced dimension for overlapping Schwarz methods
A new reduced dimension adaptive GDSW (Generalized Dryja-Smith-Widlund) overlapping Schwarz method for linear second-order elliptic problems in three dimensions is introduced. It is robust with respect to large contrasts of the coefficients of the partial differential equations. The condition number bound of the new method is shown to be independent of the coefficient contrast and only dependent on a user-prescribed tolerance. The interface of the nonoverlapping domain decomposition is partitioned into nonoverlapping patches. The new coarse space is obtained by selecting a few eigenvectors of certain local eigenproblems which are defined on these patches. These eigenmodes are energy-minimally extended to the interior of the nonoverlapping subdomains and added to the coarse space. By using a new interface decomposition the reduced dimension adaptive GDSW overlapping Schwarz method usually has a smaller coarse space than existing GDSW and adaptive GDSW domain decomposition methods. A robust condition number estimate is proven for the new reduced dimension adaptive GDSW method which is also valid for existing adaptive GDSW methods. Numerical results for the equations of isotropic linear elasticity in three dimensions confirming the theoretical findings are presented
Village Water Ozonation System
The Village Water Ozonation System (VWOS) team’s core mission statement is to provide economically sustainable and culturally sensitive drinking water solutions for communities, to empower communities with the ability to properly maintain their drinking water supply, and to transform people’s lives by decreasing the occurrences of waterborne diseases.
Currently, the VWOS team is partnering with Friends in Action to design and implement two drinking water treatment systems for the community living on Rama Cay, an island in the Bluefields Lagoon on the eastern coastline of Nicaragua. The wells on the island are contaminated with E. coli and other bacteria and contain high levels of salt that cause the water to be unhealthy, distasteful, and corrosive to metal equipment in the system. The team hopes to design a system that will disinfect the water, remove salinity from the well water with a safe and efficient disposal of all byproducts, and decrease corrosion agents.
VWOS is partnering with Forward Edge International for the third time (Nicaragua 2009 and Mexico 2016) to design water treatment systems for communities in Oaxaca, Mexico and Kijabe, Kenya. The system for Oaxaca is ready for implementation and awaits availability to travel. The system for Kijabe is in the initial stage of communicating with the client on specifics for the design.https://mosaic.messiah.edu/engr2021/1018/thumbnail.jp
Village Water Ozonation System
The Village Water Ozonation System (VWOS) team’s core mission is to provide economically sustainable and culturally sensitive drinking water solutions for communities, to empower them with the ability to properly maintain their drinking water supply, and to transform people’s lives by decreasing the occurrences of waterborne diseases. Currently, the VWOS team is partnering with Friends in Action to implement two drinking water treatment systems this summer for the community living on Rama Cay, an island in Nicaragua. The wells on the island have a high salt content and are contaminated with bacteria which makes the water unsafe to drink; therefore, these two systems consist of a Reverse Osmosis unit, a UV light and other filters to ensure clean water. VWOS is also partnering with Forward Edge International to serve Mama Beth\u27s Children\u27s Home in Kijabe, Kenya. Mama Beth\u27s serves approximately 250 children every day but their water source is heavily contaminated with bacteria. VWOS is designing a chlorination system that will provide safe water for the students with plans to implement it in the summer of 2023.
Funding for this work provided by The Collaboratory for Strategic Partnerships and Applied Research.https://mosaic.messiah.edu/engr2022/1021/thumbnail.jp
Online optimal experimental re-design in robotic parallel fed-batch cultivation facilities
We present an integrated framework for the online optimal experimental re-design applied to parallel nonlinear dynamic processes that aims to precisely estimate the parameter set of macro kinetic growth models with minimal experimental effort. This provides a systematic solution for rapid validation of a specific model to new strains, mutants, or products. In biosciences, this is especially important as model identification is a long and laborious process which is continuing to limit the use of mathematical modeling in this field. The strength of this approach is demonstrated by fitting a macro-kinetic differential equation model for Escherichia coli fed-batch processes after 6 h of cultivation. The system includes two fully-automated liquid handling robots; one containing eight mini-bioreactors and another used for automated at-line analyses, which allows for the immediate use of the available data in the modeling environment. As a result, the experiment can be continually re-designed while the cultivations are running using the information generated by periodical parameter estimations. The advantages of an online re-computation of the optimal experiment are proven by a 50-fold lower average coefficient of variation on the parameter estimates compared to the sequential method (4.83% instead of 235.86%). The success obtained in such a complex system is a further step towards a more efficient computer aided bioprocess development. Biotechnol. Bioeng. 2017;114: 610–619. © 2016 Wiley Periodicals, Inc.BMBF, 02PJ1150, Verbundprojekt: Plattformtechnologien für automatisierte Bioprozessentwicklung (AutoBio); Teilprojekt: Automatisierte Bioprozessentwicklung am Beispiel von neuen Nukleosidphosphorylase
A critical review of the formation of mono- and dicarboxylated metabolic intermediates of alkylphenol polyethoxylates during wastewater treatment and their environmental significance
This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ 2010 Taylor & Francis.Alkylphenoxyacetic acids, the metabolic biodegradation products of alkylphenol ethoxylates, are commonly found in wastewaters and sewage effluents. These persistent hydrophilic derivatives possess intrinsic estrogenic activity, which can mimic natural hormones. Their concentrations increase through the sewage treatment works as a result of biodegradation and biotransformation, and when discharged can disrupt endocrine function in fish. These acidic metabolites represent the dominant alkylphenolic compounds found in wastewater effluent and their presence is cause for concern as, potentially, through further biotransformation and biodegradation, they can act as sources of nonylphenol, which is toxic and estrogenic. The authors aim to assess the mechanisms of formation as well as elimination of alkylphenoxyacetic acids within conventional sewage treatment works with the emphasis on the activated sludge process. In addition, they evaluate the various factors influencing their degradation and formation in laboratory scale and full-scale systems. The environmental implications of these compounds are considered, as is the need for tertiary treatment processes for their removal
A decade of experience with injuries to the gallbladder
Article deposited according to publisher policy posted on SHERPA/RoMEO, 05/08/2010.YesFunding provided by the Open Access Authors Fund
Siderophore production by Bacillus megaterium : effect of growth-phase and cultural conditions
Siderophore production by Bacillus megaterium was detected, in an iron-deficient culture medium, during the exponential growth phase, prior to the sporulation, in the presence of glucose; these results suggested that the onset of siderophore production did not require glucose depletion and was not related with the sporulation. The siderophore production by B. megaterium was affected by the carbon source used. The growth on glycerol promoted the very high siderophore production (1,182 μmol g−1 dry weight biomass); the opposite effect was observed in the presence of mannose (251 μmol g−1 dry weight biomass). The growth in the presence of fructose, galactose, glucose, lactose, maltose or sucrose, originated similar concentrations of siderophore (546–842 μmol g−1 dry weight biomass). Aeration had a positive effect on the production of siderophore. Incubation of B. megaterium under static conditions delayed and reduced the growth and the production of siderophore, compared with the incubation in stirred conditions.The authors thank Porto University/Totta Bank for their financial support through the project "Microbiological production of chelating agents" (Ref: 180). The authors also thank the Fundacao para a Ciencia e a Tecnologia (FCT) through the Portuguese Government for their financial support of this work through the grants Strategic project-LA23/2013-2014 (IBB) and PEST-C/EQB/LA0006/2011 (REQUIMTE). Manuela D. Machado gratefully acknowledges the postdoctoral (SFRH/BPD/72816/2010) grant from FCT
Differences in Immunoglobulin Light Chain Species Found in Urinary Exosomes in Light Chain Amyloidosis (AL)
Renal involvement is a frequent consequence of plasma cell dyscrasias. The most common entities are light chain amyloidosis, monoclonal immunoglobulin deposition disease and myeloma cast nephropathy. Despite a common origin, each condition has its own unique histologic and pathophysiologic characteristic which requires a renal biopsy to distinguish. Recent studies have shown urinary exosomes containing kidney-derived membrane and cytosolic proteins that can be used to probe the proteomics of the entire urinary system from the glomerulus to the bladder. In this study, we analyzed urine exosomes to determine the differences between exosomes from patients with light chain amyloidosis, multiple myeloma, monoclonal gammopathy of undetermined significance, and non-paraproteinemia related kidney disease controls. In patients with light chain amyloidosis, multiple myeloma and monoclonal gammopathy of undetermined significance, immunoreactive proteins corresponding to monomeric light chains were found in exosomes by western blot. In all of the amyloidosis samples with active disease, high molecular weight immunoreactive species corresponding to a decamer were found which were not found in exosomes from the other diseases or in amyloidosis exosomes from patients in remission. Few or no light chains monomeric bands were found in non-paraproteinemia related kidney disease controls. Our results showed that urinary exosomes may have tremendous potential in furthering our understanding of the pathophysiology and diagnosis of plasma cell dyscrasia related kidney diseases
Hyperacute Directional Hearing and Phonotactic Steering in the Cricket (Gryllus bimaculatus deGeer)
Background: Auditory mate or prey localisation is central to the lifestyle of many animals and requires precise directional hearing. However, when the incident angle of sound approaches 0u azimuth, interaural time and intensity differences gradually vanish. This poses a demanding challenge to animals especially when interaural distances are small. To cope with these limitations imposed by the laws of acoustics, crickets employ a frequency tuned peripheral hearing system. Although this enhances auditory directionality the actual precision of directional hearing and phonotactic steering has never been studied in the behaviourally important frontal range. Principal Findings: Here we analysed the directionality of phonotaxis in female crickets (Gryllus bimaculatus) walking on an open-loop trackball system by measuring their steering accuracy towards male calling song presented at frontal angles of incidence. Within the range of 630u, females reliably discriminated the side of acoustic stimulation, even when the sound source deviated by only 1u from the animal’s length axis. Moreover, for angles of sound incidence between 1u and 6u the females precisely walked towards the sound source. Measuring the tympanic membrane oscillations of the front leg ears with a laser vibrometer revealed between 0u and 30u a linear increasing function of interaural amplitude differences with a slope of 0.4 dB/u. Auditory nerve recordings closely reflected these bilateral differences in afferent response latency and intensity that provide the physiological basis for precise auditory steering
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