811 research outputs found
Life Tables of Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae): with a Mathematical Invalidation for Applying the Jackknife Technique to the Net Reproductive Rate
Life table data for the melon fly, Bactrocera cucurbitae (Coquillett), reared on cucumber (Cucumis sativus L.) were collected under laboratory and simulated field conditions. Means and standard errors of life table parameters were estimated for two replicates using the jackknife technique. At 25ºC, the intrinsic rates of increase (_r_) found for the two replicates were 0.1354 and 0.1002 day-1, and the net reproductive rates (_R_~0~) were 206.3 and 66.0 offspring, respectively. When the cucumbers kept under simulated field conditions were covered with leaves, the _r_ and _R_~0~ for the two replicates were 0.0935 and 0.0909 day-1, 17.5 and 11.4 offspring, respectively. However, when similar cucumbers were left uncovered, the _r_ and _R_~0~ for the two replicates were 0.1043 and 0.0904 day-1, and 27.7 and 10.1 offspring, respectively. Our results revealed that considerable variability between replicates in both laboratory and field conditions is possible; this variability should be taken into consideration in data collection and application of life tables. Mathematical analysis has demonstrated that applying the jackknife technique results in unrealistic pseudo-_R_~0~ and overestimation of its variance. We suggest that the jackknife technique should not be used for the estimation of variability of _R_~0~
An effective long-range attraction between protein molecules in solutions studied by small angle neutron scattering
Small angle neutron scattering intensity distributions taken from cytochrome
C and lysozyme protein solutions show a rising intensity at very small wave
vector, Q, which can be interpreted in terms of the presence of a weak
long-range attraction between protein molecules. This interaction has a range
several times that of the diameter of the protein molecule, much greater than
the range of the screened electrostatic repulsion. We show evidence that this
long-range attraction is closely related to the type of anion present and ion
concentration in the solution
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Spontaneous forward Brillouin scattering in carbon disulfide
In recent years, guided acoustic wave Brillouin scattering has become an important tool in photonics, serving as the basis for everything from new forms of information processing to silicon lasers. Due to low losses and long interaction lengths, fiber optic systems offer an intriguing platform to harness these guided-wave light-sound interactions. However, within typical fiber optic systems these interactions are exceedingly weak—requiring complex microstucturing to yield appreciable light-sound coupling. Here, we enhance this light-sound coupling by using a CS2-filled liquid core optical fiber. Owing to tight confinement of the optical and acoustic modes within the fiber core, as well as the large electrostrictive response of CS2, this system yields an unprecedented forward Brillouin gain for a fiber optic system. To demonstrate this physics, we measure multipeaked spontaneous forward Brillouin scattering power spectra, yielding information about the fiber geometry, material properties, and acousto-optic coupling strength. To interpret these data, we simulate the spontaneous Brillouin scattering power spectrum for this fiber system. These results reveal that hybridized acoustic excitations within the fiber core and cladding produce this characteristic multipeaked power spectrum. In the future, the large forward Brillouin coupling, long interaction lengths, and low losses of liquid-core fibers may enable new forms of distributed sensing, lasers with customizable emission, and physics including continuum optomechanical cooling.Air Force Office of Scientific Research (AFOSR) [FA9550-15-1-0389]This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]
Identification of \u3ci\u3eErwinia rhapontici\u3c/i\u3e as the Causal Agent of Crown and Shoot Rot and Pink Seed of Pea in Nebraska
Over the last five years, the production of dry yellow peas (Pisum sativum L.) has been increasing in Nebraska and other areas of the Central High Plains, according to a USDA report (Jasa 2013). Dry pea is a short-season crop with a low water requirement, making it a good rotational crop for the high plains. We have noted bacterial pathogens, potentially a disease complex, that may negatively impact the production of pea in this region, and one of the emerging pathogens is Erwinia rhapontici. This pathogen is a gram-negative bacterium that has been reported from soil, seed, and different plant tissues, causing pink seed, crown rot, shoot and stem rot, blossom rot, or soft rot on more than 20 plant hosts, including pea (Huang et al. 2003). The disease was first reported on pea in the United States from Montana in 2002 and was later found in North Dakota in 2006 (Wise et al. 2008). Erwinia rhapontici belongs to the carotovora subgroup of Erwinia. Unlike many members of the soft rot carotovora subgroup that produces pectolytic enzyme, E. rhapontici does not degrade pectate. The organism is capable of fermenting glucose, fructose, maltose, and sucrose. Also, it produces a diffusible pink pigment on sucrose-peptone agar but not on potato dextrose agar nor nutrient agar. However, it has been shown that some strains may not produce pink pigments regardless of the type of media used (Huang et al. 2003). Proferrosamine A has been identified in the pink pigment produced, it is associated with iron deficiency in plants, and was suspected by Huang et al. (2003) as partly a pathogenicity determinant and virulence factor of E. rhapontici
Kaluza-Klein Dark Matter
We propose that cold dark matter is made of Kaluza-Klein particles and
explore avenues for its detection. The lightest Kaluza-Klein state is an
excellent dark matter candidate if standard model particles propagate in extra
dimensions and Kaluza-Klein parity is conserved. We consider Kaluza-Klein gauge
bosons. In sharp contrast to the case of supersymmetric dark matter, these
annihilate to hard positrons, neutrinos and photons with unsuppressed rates.
Direct detection signals are also promising. These conclusions are generic to
bosonic dark matter candidates.Comment: 4 pages, 3 figures, discussion of spin-independent cross section
clarified, references added, published versio
Evaluation of a wild white-tailed deer population management program for controlling chronic wasting disease in Illinois, 2003–2008
AbstractWe evaluated population management programs for controlling chronic wasting disease (CWD) in wild white-tailed deer in Illinois between November 2002 and March 2008. The intervention consisted of measures of deer removal from three deer population control programs: Illinois Department of Natural Resources culling, deer population control permits and nuisance deer removal permits. We included in the analysis a total of 14,650 white-tailed deer CWD test results. These data also included location and demographic data collected from both deer harvested in the interventions as well as deer from hunter harvests and deer vehicle collisions. We quantified intervention pressures as the number of years of intervention, the total number of deer removed and the average number of deer removed per year. We accounted for temporal and spatial variations of intervention by using mixed logistic regression to model the association between intervention pressures and CWD prevalence change. The results showed that deer population management intervention as practiced in Illinois during the study period was negatively associated with CWD prevalence and the strength of association varied depending on age of deer and the measure of intervention pressure. The population management programs showed a more consistent association with reduced CWD prevalence in fawn and yearling white-tailed deer than in adult deer. Our results also suggested that frequent and continuing intervention events with at least moderate intensity of culling were needed to reduce CWD prevalence. A longer study period, however, is needed to make a more definite conclusion about the effectiveness of similar population management programs for controlling CWD in wild white-tailed deer
A moment kernel machine for clinical data mining to inform medical decision making
Machine learning-aided medical decision making presents three major challenges: achieving model parsimony, ensuring credible predictions, and providing real-time recommendations with high computational efficiency. In this paper, we formulate medical decision making as a classification problem and develop a moment kernel machine (MKM) to tackle these challenges. The main idea of our approach is to treat the clinical data of each patient as a probability distribution and leverage moment representations of these distributions to build the MKM, which transforms the high-dimensional clinical data to low-dimensional representations while retaining essential information. We then apply this machine to various pre-surgical clinical datasets to predict surgical outcomes and inform medical decision making, which requires significantly less computational power and time for classification while yielding favorable performance compared to existing methods. Moreover, we utilize synthetic datasets to demonstrate that the developed moment-based data mining framework is robust to noise and missing data, and achieves model parsimony giving an efficient way to generate satisfactory predictions to aid personalized medical decision making
Diabetes Education with a Teaching Kitchen Intervention Can Improve Hemoglobin A1c for Type 2 Diabetics Compared to Traditional Diabetes Education
AuthorsJill Christensen MD MPH Providence Milwaukie HospitalHeidi Davis MSW Providence Milwaukie HospitalCharlotte Navarre RN Providence Milwaukie HospitalHsin-Fang Li PHD Providence Medical Data Research CenterKathy Schwab MPH RDN Providence Health EducationRichard O’Neil MBA Providence Planning Analyst
Title Diabetes Education with a Teaching Kitchen Intervention Can Improve Hemoglobin A1c for Type 2 Diabetics Compared to Traditional Diabetes Education
Purpose The Providence Milwaukie Community Teaching Kitchen offers health-focused, budget friendly cooking classes for patients. In 2019, we piloted diabetes education classes with an added hands-on culinary session. This study compares the change in hemoglobin A1c for patients who participated in the pilot with those in the standard curriculum and those referred to diabetes education but did not enroll.
Methods This retrospective analysis compared change in hemoglobin A1c for all patients referred to diabetes education in the Providence Northern Oregon region in 2019. Patients referred to diabetes education but not enrolled were considered a control group. To balance patient characteristics (e.g. age, gender, and pre-A1c score), two-to-one propensity score matching method was used to identify two matched controls for each enrollee. Change in hemoglobin A1c from baseline to 3-6 months were compared among matched comparison groups.
Results 13,582 patients were identified including 19 patients enrolled in diabetes education plus kitchen class, 640 patients in traditional diabetes education, and 12,923 patients referred but did not enroll. After matching, 1,318 matched patients were selected from the non-enrollees as the control group. The change in hemoglobin A1c was -0.49, -0.81, and -0.95 for the control group, diabetes education group, and diabetes education group with kitchen classes, respectively. Compared to the control group, both diabetes education groups had a greater reduction in hemoglobin A1c (difference of 0.32, 95% Confidence Interval [CI]=0.17, 0.48 for the diabetes education group; difference of 0.46, 95% CI=-0.28, 1.19) for the diabetes plus kitchen class group). Even though the diabetes education plus kitchen intervention had the largest reduction in hemoglobin A1c, the sample was small with large variation.
Conclusions Integrating a teaching kitchen component into the traditional diabetes education curriculum is a promising approach that can further improve initial biometric outcomes. Future studies are warranted to demonstrate clinical effectiveness of this enhanced intervention.
Financial Support Health Share Oregon Coordinated Care Organizationhttps://digitalcommons.psjhealth.org/milwaukie_family/1004/thumbnail.jp
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