15,934 research outputs found
Texas Forestry Paper No. 26
Aerial photograph use in industrial forest management in the south, 1970 and 1974https://scholarworks.sfasu.edu/texas_forestry_papers/1014/thumbnail.jp
Solar wind-magnetosphere coupling and the distant magnetotail: ISEE-3 observations
ISEE-3 Geotail observations are used to investigate the relationship between the interplanetary magnetic field, substorm activity, and the distant magnetotail. Magnetic field and plasma observations are used to present evidence for the existence of a quasi-permanent, curved reconnection neutral line in the distant tail. The distance to the neutral line varies from absolute value of X = 120 to 140 R/sub e near the center of the tail to beyond absolute value of X = 200 R/sub e at the flanks. Downstream of the neutral line the plasma sheet magnetic field is shown to be negative and directly proportional to negative B/sub z in the solar wind as observed by IMP-8. V/sub x in the distant plasma sheet is also found to be proportional to IMF B/sub z with southward IMF producing the highest anti-solar flow velocities. A global dayside reconnection efficiency of 20 +- 5% is derived from the ISEE-3/IMP-8 magnetic field comparisons. Substorm activity, as measured by the AL index, produces enhanced negative B/sub z and tailward V/sub x in the distant plasma sheet in agreement with the basic predictions of the reconnection-based models of substorms. The rate of magnetic flux transfer out of the tail as a function of AL is found to be consistent with previous near-Earth studies. Similarly, the mass and energy fluxes carried by plasma sheet flow down the tail are consistent with theoretical mass and energy budgets for an open magnetosphere. In summary, the ISEE-3 Geotail observations appear to provide good support for reconnection models of solar wind-magnetosphere coupling and substorm energy rates
Implications of Biomechanical Characters of Subterranean Clover on Feeding by Redlegged Earth Mite and Intake by Sheep
The biomechanical strength of cultivars of subterranean clover (Trifolium subterraneum) that were either resistant or susceptible to feeding by redlegged earth mite was measured as the force required to penetrate their leaves with a small, tubular punch. Cotyledons and trifoliate leaves of cultivars resistant to redlegged earth mite had a higher resistance to penetration than cultivars susceptible to redlegged earth mite. Cotyledons needed a higher force to penetrate than trifoliate leaves. The possible implications for intake by ruminants of differences between the cultivars in biomechanical characters are also considered
COVID-19, Equity and Menâs Health: Using Evidence to Inform Future Public Health Policy, Practice and Research Responses in Pandemics
In March 2020, the World Health Organization (WHO) announced that COVID-19 (novel coronavirus) reflected a global pandemic. Early epidemiological analyses demonstrated that boys and men have similar rates of COVID-19 infection to girls and women. However, boys and men appear to be disproportionately impacted with respect to severity and mortality, including those from marginalised or minority backgrounds. Yet, considerations of sex and gender, and their relationship to health and social inequities, have been absent from recent COVID-19 policy and practice pandemic responses. This evidence-based commentary discusses the nexus between COVID-19, equity, and boys and menâs health from a broad public health perspective. Using scholarship about intersections between race and gender; and poverty, social determinants of health, and gender; we explain why a health equity lens is important to address the health and social inequities boys and men face during pandemics. This contribution provides guidance about future global public healthpandemic responses for societyâs most vulnerable groups of boys and men
An Improved Experimental Limit on the Electric Dipole Moment of the Neutron
An experimental search for an electric-dipole moment (EDM) of the neutron has
been carried out at the Institut Laue-Langevin (ILL), Grenoble. Spurious
signals from magnetic-field fluctuations were reduced to insignificance by the
use of a cohabiting atomic-mercury magnetometer. Systematic uncertainties,
including geometric-phase-induced false EDMs, have been carefully studied. Two
independent approaches to the analysis have been adopted. The overall results
may be interpreted as an upper limit on the absolute value of the neutron EDM
of |d_n| < 2.9 x 10^{-26} e cm (90% CL).Comment: 5 pages, 2 figures. The published PRL is slightly more terse (e.g. no
section headings) than this version, due to space constraints. Note a small
correction-to-a-correction led to an adjustment of the final limit from 3.0
to 2.9 E-26 e.cm compared to the first version of this preprin
Interval Subroutine Library Mission
We propose the collection, standardization, and distribution of a full-featured production quality library for reliable scientific computing with routines using interval techniques for use by the wide community of applications developers
Exact Optics: A unification of optical telescope design
A perfect focus telescope is one in which all rays parallel to the axis meet
at a point and give equal magnification there. It is shown that these two
conditions define the shapes of both primary and secondary mirrors. Apart from
scale, the solution depends upon two parameters, , which gives the mirror
separation in terms of the effective focal length, and , which gives the
relative position of the final focus in that unit. The two conditions ensure
that the optical systems have neither spherical aberration nor coma, no matter
how fast the ratio. All known coma--free systems emerge as approximate
special cases. In his classical paper, K. Schwarzschild studied all two mirror
systems whose profiles were conic sections. We make no such a priori shape
conditions but demand a perfect focus and solve for the mirrors' shapes.Comment: 11 pages, LaTex ([alleqno,epsfig]{mn}), 7 Figures (eps), accepted by
MNRA
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