2,667 research outputs found
New Records of Michigan Cicadidae (Homoptera), With Notes on the Use of Songs to Monitor Range Changes
We present records of Diceroprocta vitripennis, Tibicen chloromera, and Tibicen pruinosa (new state record) in Michigan. Monitoring geographic range changes and population size differences by song suggests several population situations for cicadas: (1) sizable populations in most areas of apparently good habitat; (2) widely separated single individuals or small populations on the edges of populated regions, representing range extensions that may be of limited duration; (3) one or a few individuals present only once, probably transferred in soil on roots, and ultimately unsuccessful. Species- specific calling songs allow sensitive measurement of species\u27 range changes
The Focal plane Detector Package on the TUNL Split-pole Spectrograph
A focal plane detector for the Enge Split-pole Spectrograph at Triangle
Universities Nuclear Laboratory has been designed. The detector package
consists of two position sensitive gas avalanche counters, a gas
proportionality energy loss section, and a residual energy scintillator. This
setup allows both particle identification and focal plane reconstruction. In
this paper we will detail the construction of each section along with their
accompanying electronics and data acquisition. Effects of energy loss
throughout the detector, ray tracing procedures, and resolution as a function
of fill pressure and bias voltage are also investigated. A measurement of the
Al reaction is used to demonstrate detector performance and to
illustrate a Bayesian method of energy calibration
Providing Economic Incentives in Environmental Regulation
CHAIRMAN BREGER: Let me welcome you to this AdministrativeConference colloquy on providing economic incentives in environmentallitigation
The Value of Bt Corn in Southwest Kansas: A Monte Carlo Simulation Approach
While most Corn Belt farmers consider planting Bt corn to control European corn borer, southwestern Kansas farmers must also take into account an array of other insect pests, including corn rootworm, spider mites, and southwestern corn borer. This research uses a decision analysis framework to estimate the expected economic value of Bt corn in southwest Kansas. Mean per acre Bt values ranged from 34.60, well above the technology fee assumed to be 5.25 per acre at a seeding rate of 30,000 seeds per acre. The minimum value over all scenarios was $8.69 per acre. Using Monte Carlo simulation, it was shown that European and southwestern corn borer infestation probabilities, expected corn price, and expected pest-free yields are important determinants of the value of Bt corn.Bt corn, decision analysis, European corn borer, integrated pest management, Monte Carlo simulation, southwestern corn borer, Crop Production/Industries,
Boundary of oxidative and overflow metabolism (boom) controller for CHO cell feed control
There is limited literature for CHO cell cultures with low batch glucose concentrations (Gowtham et al. 2017; Lu et al. 2005; Wong et al. 2005). Work like Xu et al. (2016) and Berry et al. (2016) have shown positive results for controlled fed-batch cultures at low glucose concentrations following standard high glucose (5-6 g/L) batch cultures. However, the Xu et al. (2016) and Berry et al. (2016) approaches still accumulate lactate. Controlling glucose earlier could potentially avoid lactate accumulation and lead to even greater improvements in culture outcomes. The objective of this project was to develop an advanced feed controller for CHO cell cultures that maximizes cell growth by maintaining the culture in a state of maximal oxidative metabolism while minimizing overflow metabolism. The Boundary of Oxidative and Overflow Metabolism (BOOM) controller periodically manipulates the feed rate while monitoring online signals to gauge the remaining oxidative “space”, in order to decide whether feed can be increased while remaining in oxidative metabolism. The Oxygen Uptake Rate (OUR) is the primary signal of interest, since it plateaus when a culture shifts from oxidative to overflow metabolism, encoding vital information about metabolic state. This project’s approach is different from past work in that the batch glucose concentrations is much lower (on the order of 1 g/L), the glucose and/or glutamine feeding begins very early in the process, and glucose feed is triggered/controlled by the off-gas sensing of the metabolic state instead of a targeted glucose concentration. During early runs several chemistry effects were observed directly due to the bolus feed additions interfering with the media-dissolved gas equilibrium. For example, a bolus feed that only contained 5 mM bicarbonate, resulted in an observed short sharp decrease in CO2 off-gas as the feed absorbed CO2 from the 5% CO2 sparge gas. Continuous feeding was introduced in subsequent runs as a means to mitigate disrupting the media-dissolved gas-equilibrium and disturbing the off-gas sensing. In order to have effective continuous feeding, the feed pump used a pulse width modulation (PWM) with a 10-minute period to allow extremely low effective feed rates required for the 1-L vessel. Two runs were used to demonstrate that the PWM feed pump could provide these very low pump feed rates for the 1-L vessel containing as little as 500 mL media. Initial glucose concentrations between 0.6 to 2.0 g/L were used (compared to 8 g/L glucose in the standard media formulation). Feedings have started between 6- and 20-hour post-inoculation. Distinct qualitative and quantitative differences have been observed in the corresponding oxygen uptake rate (OTR) responses due to the feeding spikes, suggesting that metabolic state can be detected. The development of the state estimator to control glucose feeding will be presented
Predicting risk of COPD in primary care:development and validation of a clinical risk score
OBJECTIVES: To develop and validate a clinical risk score to identify patients at risk of chronic obstructive pulmonary disease (COPD) using clinical factors routinely recorded in primary care. DESIGN: Case–control study of patients containing one incident COPD case to two controls matched on age, sex and general practice. Candidate risk factors were included in a conditional logistic regression model to produce a clinical score. Accuracy of the score was estimated on a separate external validation sample derived from 20 purposively selected practices. SETTING: UK general practices enrolled in the Clinical Practice Research Datalink (1 January 2000 to 31 March 2006). PARTICIPANTS: Development sample included 340 practices containing 15 159 newly diagnosed COPD cases and 28 296 controls (mean age 70 years, 52% male). Validation sample included 2259 cases and 4196 controls (mean age 70 years, 50% male). MAIN OUTCOME MEASURES: Area under the receiver operator characteristic curve (c statistic), sensitivity and specificity in the validation practices. RESULTS: The model included four variables including smoking status, history of asthma, and lower respiratory tract infections and prescription of salbutamol in the previous 3 years. It had a high average c statistic of 0.85 (95% CI 0.83 to 0.86) and yielded a sensitivity of 63.2% (95% CI 63.1 to 63.3) and specificity 87.4% (95% CI 87.3 to 87.5). CONCLUSIONS: Risk factors associated with COPD and routinely recorded in primary care have been used to develop and externally validate a new COPD risk score. This could be used to target patients for case finding
Tissue-specific calibration of extracellular matrix material properties by transforming growth factor-beta and Runx2 in bone is required for hearing
Publisher version: http://www.nature.com/embor/journal/v11/n10/full/embor2010135.htmlDA - 20100917 IS - 1469-3178 (Electronic) IS - 1469-221X (Linking) LA - ENG PT - JOURNAL ARTICLEDA - 20100917 IS - 1469-3178 (Electronic) IS - 1469-221X (Linking) LA - ENG PT - JOURNAL ARTICLEDA - 20100917 IS - 1469-3178 (Electronic) IS - 1469-221X (Linking) LA - ENG PT - JOURNAL ARTICLEPhysical cues, such as extracellular matrix stiffness, direct cell differentiation and support tissue-specific function. Perturbation of these cues underlies diverse pathologies, including osteoarthritis, cardiovascular disease and cancer. However, the molecular mechanisms that establish tissue-specific material properties and link them to healthy tissue function are unknown. We show that Runx2, a key lineage-specific transcription factor, regulates the material properties of bone matrix through the same transforming growth factor-beta (TGFbeta)-responsive pathway that controls osteoblast differentiation. Deregulated TGFbeta or Runx2 function compromises the distinctly hard cochlear bone matrix and causes hearing loss, as seen in human cleidocranial dysplasia. In Runx2(+/-) mice, inhibition of TGFbeta signalling rescues both the material properties of the defective matrix, and hearing. This study elucidates the unknown cause of hearing loss in cleidocranial dysplasia, and demonstrates that a molecular pathway controlling cell differentiation also defines material properties of extracellular matrix. Furthermore, our results suggest that the careful regulation of these properties is essential for healthy tissue functio
An Untriggered Search for Optical Bursts
We present an untriggered search for optical bursts with the ROTSE-I
telephoto array. Observations were taken which monitor an effective 256 square
degree field continuously over 125 hours to m_{ROTSE}=15.7. The uniquely large
field, moderate limiting magnitude and fast cadence of 10 minutes permits
transient searches in a new region of sensitivity. Our search reveals no
candidate events. To quantify this result, we simulate potential optical bursts
with peak magnitude, m_{p}, at t=10 s, which fade as f=(\frac{t}{t_{0}})
^{\alpha_{t}}, where \alpha_t < 0. Simple estimates based on observational
evidence indicate that a search of this sensitivity begins to probe the
possible region occupied by GRB orphan afterglows. Our observing protocol and
image sensitivity result in a broad region of high detection efficiency for
light curves to the bright and slowly varying side of a boundary running from
[\alpha_{t},m_{p}]=[-2.0,6.0] to [-0.3,13.2]. Within this region, the
integrated rate of brief optical bursts is less than 1.1\times 10^{-8} {\rm
s}^{-1} {\rm deg}^{-2}. At 22 times the observed GRB rate from BATSE,
this suggests a limit on \frac{\theta_{opt}}{\theta_{\gamma}}\lesssim 5 where
\theta_{opt} and \theta_{\gamma} are the optical and gamma-ray collimation
angles, respectively. Several effects might explain the absence of optical
bursts, and a search of the kind described here but more sensitive by about 4
magnitudes should offer a more definitive probe.Comment: 8 pages, 6 figures, 1 tabl
Bostonia. Volume 4
Founded in 1900, Bostonia magazine is Boston University's main alumni publication, which covers alumni and student life, as well as university activities, events, and programs
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