The Effects of Size of Sampling Area and Dilution on Leucocyte Counts in a Hemocytometer

Author Institution: The University of Dayton, Dayton, OhioWith nearly 5000 areas examined, the comparison of a Poisson distribution to the distribution of leucocytes in a hemocytometer chamber at both 1:100 and 1:25 dilutions indicated a poor fit (P= <0.0001), a non-random distribution. In a series of leucocyte determinations from a young, male university student comparing 28 counts from 18 mm2 (both chambers) with 28 from 9 mm2, and 28 from 4 mm2 (the usual standard), the mean from the 18 mm2 counts was not significantly different from that of the 9 mm2 counts. However, both the means of the 18 mm2 counts and the 9 mm2 counts were significantly different from that of the 4 mm2 counts (P = 0.02 and 0.035 respectively). Forty-two counts at 1:100 dilution had a mean not significantly different from that of 42 counts at 1:20 dilution (P = 0.06). It appears that the counts from the 18 mm2 area at 1:100 dilution are the most reliable and are therefore recommended for critical research determinations. Fourteen such counts had the most restricted range and the lowest standard deviation of any of the six combinations

Vast Migrating Armies of the Millipede, Pseudo-Polydesmus Serratus (Say) in the Dayton Region

Author Institution: Department of Biology, University of Dayton, Dayton, Ohi

Effect of Sustained Hand Grip Isometric Exercise on the Response of Erythrocyte 2,3-diphosphoglycerate in Untrained Men

Author Institution: Department of Biology, University of DaytonExperiments were designed to examine the role of erythrocyte 2,3-diphosphoglycerate (2,3-DPG) in a purely isometric exercise (hand-grip dynamometer) using the human arm as an in vivo model, since the literature contains very little information concerning the contribution of this phosphate in such exercise. 2,3-DPG provides a compensatory adjustment to facilitate oxygen delivery during hypoxic conditions. Its breakdown occurs under acidosis. Twelve untrained males, age ranging from 19 to 22 years, exercised using a hand-grip dynamometer at a sustained contraction of load greater than 50% of their individual maximal voluntary contractions (MVC) until exhaustion occurred between 1.8-3.2 min. There were no significant post-exercise changes in the mean levels of 2,3-DPG when measured as either |imolml * red blood cell (RBC) or mol-mol1 hemoglobin (Hb) immediately after exercise and 50 min after exercise even though immediate post-exercise increase in mean lactate levels and decrease in mean pH levels were significant (P <0.001). It is concluded that the duration of exercise in the present study was too brief for acidosis to affect 2,3-DPG metabolism

A Case of Intestinal Myiasis by Musca Domestica in a Laboratory Assistant

Author Institution: Department of Biology, Cedarville College, Cedarville, Ohi

Primary Adenocarcinoma of the Gland of the Nictitating Membrane in a Cat

An 11-year-old, neutered, male domestic shorthair was presented with a five-month history of recurrent, unilateral, seromucoid discharge from the right eye. A verrucous mass extended from the posterior aspect of the nictitating membrane. Adenocarcinoma of the gland of the nictitating membrand (GNM) was diagnosed upon biopsy. The cat subsequently developed metastases to the lungs, pleura, mediastinum, liver, and kidneys and died six months after clinical signs first were observed. Little is known about the biological behavior of adenocarcinoma of the GNM in cats. This is the first report that describes the natural progression of this disease

Soil Fungi Alter Interactions Between the Invader Centaurea Maculosa and North American Natives

Soil microbes may affect the way exotic invasive plants interact with native neighbors. We investigated the effects of soil fungi on interactions between the invasive weed Centaurea maculosa (spotted knapweed) and six species native to the intermountain prairies of the northwestern United States. We also compared the effect of C. maculosa on the composition of the soil microbial community to that of the native species. In the field, fungicide (Benomyl) reduced AM mycorrhizal colonization of C. maculosa roots by \u3e80%. Fungicide did not significantly reduce non-AM fungi. When grown alone, the biomass of C. maculosa was not affected by the fungicide application. However, depending on the combination of native competitor and fungicide, C. maculosa biomass varied from 10-fold decreases to 1.9-fold increases. In untreated soils, C. maculosa grew larger in the presence of Festuca idahoensis or Koeleria cristata than when alone. When fungicide was applied these positive effects of Festuca and Koeleria on C. maculosa did not occur. A third native grass, Pseudoroegneria spicata, had much stronger competitive effects on C. maculosa than Festuca or Koeleria, and fungicide reduced the competitive effects of Pseudoroegneria. Fungicide increased Centaurea biomass when competing with the forb Gallardia aristata. However, fungicide did not affect the way two other forbs; Achillea millefolium and Linum lewisii, interacted with C. maculosa. Rhizosphere microbial communities in the root zones of the three native bunchgrass species differed from that of C. maculosa. However, despite the strong effects of soil fungi in field interactions and differences in microbial community composition, soil biota from different plant rhizospheres did not affect the growth of C. maculosa in the absence of native competitors in greenhouse experiments. Our results suggest that successful invasions by exotic plant species can be affected by complex and often beneficial effects of local soil microbial communities. These effects were not manifest as simple direct effects, but become apparent only when native plants, invasive plants, and soil microbial communities were interacting at the same time

Captain Buzz

This is the author accepted manuscript. The final version is available from ACM at https://dl.acm.org/citation.cfm?id=2750682.Fully autonomous hobbyist drones are typically controlled using bespoke microcontrollers, or general purpose low-level controllers such as the Arduino. However, these devices only have limited compute power and sensing capabilities, and do not easily provide cellular connectivity options. We present Captain Buzz, an Android smartphone app capable of piloting a delta-wing glider autonomously. Captain Buzz can control servos directly via pulse width modulation sig- nals transmitted over the smartphone audio port. Compared with traditional approaches to building an autopilot, Cap- tain Buzz allows users to leverage existing Android libraries for flight attitude determination, provides innovative use- cases, allows users to reprogram their autopilot mid-flight for rapid prototyping, and reduces the cost of building drones.This work was supported by Google Inc., the Engineering and Physical Sciences Research Council; and CSR, Cambridge