1,316 research outputs found
System and method for object localization
A computer-assisted method for localizing a rack, including sensing an image of the rack, detecting line segments in the sensed image, recognizing a candidate arrangement of line segments in the sensed image indicative of a predetermined feature of the rack, generating a matrix of correspondence between the candidate arrangement of line segments and an expected position and orientation of the predetermined feature of the rack, and estimating a position and orientation of the rack based on the matrix of correspondence
Why aren’t signals of female quality more common?
ArticleHighlights
In most species females are less ornamented than males.
We suggest a novel reason for this pattern.
If females signal their sexual quality, they may suffer increased sexual harassment.
Ornaments could therefore be especially costly for females.We thank the Editor and the anonymous referees for helpful comments and the Leverhulme Trust, NERC and the Royal Society for funding
Plan of Greely Institute Addition, Main Street, Cumberland, Maine, 1956
Plan of Greely Institute Addition, Main Street, Cumberland, Maine was created by Alonzo J. Harriman Inc. in 1956. Scale 1 =8\u27.https://digitalmaine.com/cumberland_plans/1206/thumbnail.jp
Plant height and hydraulic vulnerability to drought and cold
Understanding how plants survive drought and cold is increasingly important as plants worldwide experience dieback with drought in moist places and grow taller with warming in cold ones. Crucial in plant climate adaptation are the diameters of water-transporting conduits. Sampling 537 species across climate zones dominated by angiosperms, we find that plant size is unambiguously the main driver of conduit diameter variation. And because taller plants have wider conduits, and wider conduits within species are more vulnerable to conduction-blocking embolisms, taller conspecifics should be more vulnerable than shorter ones, a prediction we confirm with a plantation experiment. As a result, maximum plant size should be short under drought and cold, which cause embolism, or increase if these pressures relax. That conduit diameter and embolism vulnerability are inseparably related to plant size helps explain why factors that interact with conduit diameter, such as drought or warming, are altering plant heights worldwide
Development policy planning in Ghana: The case of health care provision
This paper examines the historical development of health policy in
Ghana within the framework of financial, geographical accessibility and the
availability of health care. Historically, health policy has been
urban biased, and largely focused on financial accessibility. Even Nkrumah's
free health care policy could not adequately address the problem of
inadequate health professionals and facilities in the rural areas.The study also
established that poverty is also largely a rural phenomenon.The poor benefit
less from the National Health Insurance Scheme (NHIS). This situation
makes the NHIS lack social equity, the very reason for its being. We
recommend that government should expand health facilities in the rural areas,
and introduce attractive incentive packages to attract and retain health
professionals in such areas. There is an urgent need for rigorous criteria
to be developed by the NHIS to identify the very poor for health insurance
premium exemptions
Combined proton NMR wideline and NMR relaxometry to study SOM-water interactions of cation-treated soils
Focusing on the idea that multivalent cations affect SOM matrix and surface, we treated peat and soil samples
by solutions of NaCl, CaCl2 or AlCl3. Water binding was characterized with low field 1H-NMR-relaxometry (20 MHz)
and 1H wideline NMR spectroscopy (400 MHz) and compared to contact angles.
From 1H wideline, we distinguished mobile water and water involved in water molecule bridges (WaMB). Large part
of cation bridges (CaB) between SOM functional groups are associated with WaMB. Unexpectedly, 1H NMRrelaxometry
relaxation rates suggest that cross-linking in the Al-containing peat is not stronger than that by Ca.
The relation between percentage of mobile water and WaMB water in the context of wettability and 1H NMR relaxation
times confirms that wettability controls the water film surrounding soil particles. Wettability is controlled by
WaMB-CaB associations fixing hydrophilic functional groups in the SOM interior. This can lead to severe water repellency.
Wettability decreases with increasing involvement of functional groups in CaB-WaMB associations. The results
demonstrate the relevance of CaB and WaMB for the dynamics of biogeochemical and hydrological processes under
field conditions, as only a few percent of organic matter can affect the physical, chemical, and biological functioning of the entire 3-phase ecosystem
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