13,781 research outputs found
Checklist of the Ants of Michigan (Hymenoptera: Formicidae)
A total of 113 species of ants is recorded by county from the state of Michigan. The list is based upon literature records and specimens in the authors\u27 collections and those of the University of Michigan Museum of Zoology and the Michigan State University Department of Entomology. The list includes 3 species in Ponerinae, 44 in Myrnucinae, 6 in Dolichoderinae, and 60 in Formicinae. Ten species represent new state records. Five distribution pat- terns are evident: statewide (39 species), southern counties only (5), southern 3/4th of Lower Peninsula (10), Lower Peninsula (17), and Upper Peninsula (2). Forty species have been collected too infrequently to determine the distribution within the state
The shape of the urine stream — from biophysics to diagnostics
We develop a new computational model of capillary-waves in free-jet flows, and apply this to the problem of urological diagnosis in this first ever study of the biophysics behind the characteristic shape of the urine stream as it exits the urethral meatus. The computational fluid dynamics model is used to determine the shape of a liquid jet issuing from a non-axisymmetric orifice as it deforms under the action of surface tension. The computational results are verified with experimental modelling of the urine stream. We find that the shape of the stream can be used as an indicator of both the flow rate and orifice geometry. We performed volunteer trials which showed these fundamental correlations are also observed in vivo for male healthy volunteers and patients undergoing treatment for low flow rate. For healthy volunteers, self estimation of the flow shape provided an accurate estimation of peak flow rate (+-2%). However for the patients, the relationship between shape and flow rate suggested poor meatal opening during voiding. The results show that self measurement of the shape of the urine stream can be a useful diagnostic tool for medical practitioners since it provides a non-invasive method of measuring urine flow rate and urethral dilation
Best-first heuristic search for multicore machines
To harness modern multicore processors, it is imperative to develop parallel versions of fundamental algorithms. In this paper, we compare different approaches to parallel best-first search in a shared-memory setting. We present a new method, PBNF, that uses abstraction to partition the state space and to detect duplicate states without requiring frequent locking. PBNF allows speculative expansions when necessary to keep threads busy. We identify and fix potential livelock conditions in our approach, proving its correctness using temporal logic. Our approach is general, allowing it to extend easily to suboptimal and anytime heuristic search. In an empirical comparison on STRIPS planning, grid pathfinding, and sliding tile puzzle problems using 8-core machines, we show that A*, weighted A* and Anytime weighted A* implemented using PBNF yield faster search than improved versions of previous parallel search proposals
Notes on ant larvae : 1989-1991
In 1976 we published "Ant Larvae: Review and Synthesis," which we regarded as a summary of our life-time of research. During the following years so many new larvae were added to our collection and so much was published about ant larvae that we decided another general treatment was desirable; so in 1986 we published a "Ten-Year Supplement" to include additions and revisions to our Memoir. In 1987 and 1988 additional material warranted a supplement to the "10-year Supplement" in 1989a. This article is the third supplement to the Memoir. In the supplement, two genera are characterized, one generic characterization is revised, and references in the literature are increased by 43. Changes in our Memoir (1976) and its supplements (1986, 1989a) are noted
Climate Change: From Science to Practice
PURPOSE OF REVIEW: Climate change poses a significant threat to human health. Understanding how climate science can be translated into public health practice is an essential first step in enabling robust adaptation and improving resiliency to climate change. RECENT FINDINGS: Recent research highlights the importance of iterative approaches to public health adaptation to climate change, enabling uncertainties of health impacts and barriers to adaptation to be accounted for. There are still significant barriers to adaptation, which are context-specific and thus present unique challenges to public health practice. The implementation of flexible adaptation approaches, using frameworks targeted for public health, is key to ensuring robust adaptation to climate change in public health practice. The BRACE framework provides an excellent approach for health adaptation to climate change. Combining this with the insights provided and by the adaptation pathways approach allows for more deliberate accounting of long-term uncertainties. The mainstreaming of climate change adaptation into public health practice and planning is important in facilitating this approach and overcoming the significant barriers to effective adaptation. Yet, the immediate and future limits to adaptation provide clear justification for urgent and accelerated efforts to mitigate climate change
Salesmanship Part of Foresters’ Job
Forestry practice should become as completely a part of our state and national life as the public school system and the Post Office Department are. The United States Forest Service established in 1905 now has more than 158,000,000 acres of Government land under its direction; is cooperating with many states under the Clark-McNary Act; has charge of a number of experiment stations, and is doing intensive research and investigative work in the Madson Laboratory; forty states have Forestry Departments and thirty states have Extension Foresters, and yet, the people in general have very little idea of what is being done or what is supposed to be done along forestry lines. They know in a vague way that something is being done here and there but have little conception of the whole problem nor realize that they, themselves, have a part in it. Progress is sure to be slow and even stopped entirely in places so long as this condition exists
The existence of time
Of those gauge theories of gravity known to be equivalent to general
relativity, only the biconformal gauging introduces new structures - the
quotient of the conformal group of any pseudo-Euclidean space by its Weyl
subgroup always has natural symplectic and metric structures. Using this metric
and symplectic form, we show that there exist canonically conjugate,
orthogonal, metric submanifolds if and only if the original gauged space is
Euclidean or signature 0. In the Euclidean cases, the resultant configuration
space must be Lorentzian. Therefore, in this context, time may be viewed as a
derived property of general relativity.Comment: 21 pages (Reduced to clarify and focus on central argument; some
calculations condensed; typos corrected
- …