13 research outputs found
The Feeding Ecology of the Gastropod Batillaria attramentaria, Chuckanut Mudflat, Washington
The deposit-feeding gastropod Batillaria attramentaria lives upon algal mat, mud, gravelly mud and gravelly sand substrates at Chuckanut Mudflat, Washington and upon homogeneous sand at Semiahmoo Spit, Washington. The efficiencies and rates·of feeding by B. attramentaria on these substrates were studied in order to determine whether an optimal foraging strategy exists in this species.
Gut content analysis of snails taken from the various substrates revealed a fairly constant diet of sediment particles and diatoms, along with occasional animal fragments. Diatoms were ingested with efficiencies ranging from 38 to 51 percent; digestive efficiency increased with increasing availability of diatoms in sediments. Snail fecal pellets contained two to seven times more organic carbon than was contained in sediments. Carbon enrichment of pellets decreased with increasing availability of carbon in the sediments.
Gut residence times for materials ingested ranged from 260 to 400 minutes and varied inversely with the percentage of mud in the sediments. Pellet egestion rates increased with increasing percentage of mud in sediments, and ranged from 0.1 to 7.0 mg snail-1 hr-1.
Results for gut content analysis, gut residence and egestion rate experiments supported the hypothesis that Batillaria attramentaria feeds selectively on mud and diatoms regardless of sediment type. Egestion rate, diatom digestion and carbon enrichment results pointed to an energy optimization strategy in this species
Measuring Bird Damage to Three Fruit Crops: A Comparison of Grower and Field Estimates
Birds are common pests in fruit orchards. They frequently consume and damage fruit resulting in decreased yields for growers. The true extent of damage is difficult to measure. Producer surveys are often implemented to estimate damage, but the accuracy of these estimates is uncertain. We compared damage estimates obtained through field studies with estimates from a producer survey for three fruit crops: wine grapes, sweet cherries, and ‘Honeycrisp’ apples. We also analyzed relationships between use of various damage management methods and levels of bird damage. We found wine grape and sweet cherry growers accurately assessed bird damage, while ‘Honeycrisp’ apple growers may overestimate damage. Growing region appears to be an important damage predictor for wine grape and sweet cherry crops. Significant relationships between management methods and damage were positive, suggesting growers only use these methods when bird damage is substantial
Proportions of bird damage in tree fruits are higher in low-fruit-abundance contexts
Frugivorous birds impose significant costs on tree fruit growers through direct consumption of fruit and grower efforts to manage birds.We documented factors that influenced tree fruit bird damage from 2012 through 2014 with a coordinated field study in Michigan, New York, and Washington. For sweet cherries, percent bird damage was higher in 2012 compared to 2013 and 2014, in Michigan and New York compared toWashington, and in blocks with more edges adjacent to non-sweet cherry land-cover types. These patterns appeared to be associated with fruit abundance patterns; 2012 was a particularly lowyield year for tree fruits in Michigan and New York and percent bird damage was high. In addition, percent bird damage to sweet and tart cherries in Michigan was higher in landscapes with low to moderate forest cover compared to higher forest cover landscapes. \u27Honeycrisp\u27 apple blocks under utility wires were marginally more likely to have greater bird damage compared to blocks without wires. We recommend growers prepare bird management plans that consider the spatial distribution of fruit and non-fruit areas of the farm. Growers should generally expect to invest more in bird management in low-yield years, in blocks isolated from other blocks of the same crop, and in blocks where trees can provide entry to the crop for frugivorous birds
The Public Repository of Xenografts enables discovery and randomized phase II-like trials in mice
More than 90% of drugs with preclinical activity fail in human trials, largely due to insufficient efficacy. We hypothesized that adequately powered trials of patient-derived xenografts (PDX) in mice could efficiently define therapeutic activity across heterogeneous tumors. To address this hypothesis, we established a large, publicly available repository of well-characterized leukemia and lymphoma PDXs that undergo orthotopic engraftment, called the Public Repository of Xenografts (PRoXe). PRoXe includes all de-identified information relevant to the primary specimens and the PDXs derived from them. Using this repository, we demonstrate that large studies of acute leukemia PDXs that mimic human randomized clinical trials can characterize drug efficacy and generate transcriptional, functional, and proteomic biomarkers in both treatment-naive and relapsed/refractory disease
In Support of a Patient-Driven Initiative and Petition to Lower the High Price of Cancer Drugs
Comment in
Lowering the High Cost of Cancer Drugs--III. [Mayo Clin Proc. 2016]
Lowering the High Cost of Cancer Drugs--I. [Mayo Clin Proc. 2016]
Lowering the High Cost of Cancer Drugs--IV. [Mayo Clin Proc. 2016]
In Reply--Lowering the High Cost of Cancer Drugs. [Mayo Clin Proc. 2016]
US oncologists call for government regulation to curb drug price rises. [BMJ. 2015
Iron status and treatment modalities in transfusion-dependent patients with myelodysplastic syndromes
Bird damage to select fruit crops: The cost of damage and the benefits of control in five states
Fruit loss to birds is a long-standing and costly problem for many producers. We conducted a survey of Honeycrisp apple, blueberry, cherry, and wine grape growers in California, Michigan, New York, Oregon, and Washington to estimate costs of bird damage and benefits of bird damage management. We also assessed grower perceptions of impacts on profits and effectiveness of bird management techniques. Current yield-loss estimates provided by growers and market price data were used to monetize current bird damage in each crop and growing region. Data on expected damage without management were used to estimate the benefits of bird damage management as it is currently being employed in the different crops and growing regions. We estimated that current bird damage costs per hectare ranged from 7267 in Washington Honeycrisp apples. Estimated benefits of bird management ranged from 36,851 in California blueberries. Aggregate bird damage in the five crops and states was estimated at 737 million to $834 million. Growers viewed most techniques for bird damage management as ineffective, or only slightly effective, and a majority of blueberry and sweet cherry growers viewed bird damage as having a significant impact on profits. Enhancing the effectiveness of bird damage management would increase both the efficiency and profitability of fruit production
Proportions of bird damage in tree fruits are higher in low-fruit-abundance contexts
Frugivorous birds impose significant costs on tree fruit growers through direct consumption of fruit and grower efforts to manage birds.We documented factors that influenced tree fruit bird damage from 2012 through 2014 with a coordinated field study in Michigan, New York, and Washington. For sweet cherries, percent bird damage was higher in 2012 compared to 2013 and 2014, in Michigan and New York compared toWashington, and in blocks with more edges adjacent to non-sweet cherry land-cover types. These patterns appeared to be associated with fruit abundance patterns; 2012 was a particularly lowyield year for tree fruits in Michigan and New York and percent bird damage was high. In addition, percent bird damage to sweet and tart cherries in Michigan was higher in landscapes with low to moderate forest cover compared to higher forest cover landscapes. \u27Honeycrisp\u27 apple blocks under utility wires were marginally more likely to have greater bird damage compared to blocks without wires. We recommend growers prepare bird management plans that consider the spatial distribution of fruit and non-fruit areas of the farm. Growers should generally expect to invest more in bird management in low-yield years, in blocks isolated from other blocks of the same crop, and in blocks where trees can provide entry to the crop for frugivorous birds