Factors Influencing the Efficacy of Forward-Looking Infrared in Polar Bear Den Detection

AbstractDenned polar bears are invisible under the snow, therefore winter-time petroleum exploration and development activities in northern Alaska have potential to disturb maternal polar bears and their cubs. Previous research determined forward looking infrared (FLIR) imagery could detect many polar bear maternal dens under the snow, but also identified limitations of FLIR imagery. We evaluated the efficacy of FLIR-surveys conducted by oil-field operators from 2004-2016. Aerial FLIR surveys detected 15 of 33 (45%) and missed 18 (55%) of the dens known to be within surveyed areas. While greater adherence to previously recommended protocols may improve FLIR detection rates, the physical characteristics of polar bear maternal dens, increasing frequencies of weather unsuitable for FLIR detections—caused by global warming, and competing “hot spots” are likely to prevent FLIR surveys from detecting maternal dens reliably enough to afford protections consonant with increasing global threats to polar bear welfare.

Download Full-text

Factors influencing adhesive bonding at the bone/implant interface

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100130201 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1114-1115

Author(s):

Julie A. Martini ◽

Robert H. Doremus

Keyword(s):

Electron Microscopy ◽

Adhesive Bonding ◽

Microscopy Study ◽

Electron Microscopy Study ◽

Bone Implant ◽

Factors Influencing ◽

Lr White ◽

Transmission Electron ◽

New Zealand White Rabbits ◽

Scanning Electron

Tracy and Doremus have demonstrated chemical bonding between bone and hydroxylapatite with transmission electron microscopy. Now researchers ponder how to improve upon this bond in turn improving the life expectancy and biocompatibility of implantable orthopedic devices.This report focuses on a study of the- chemical influences on the interfacial integrity and strength. Pure hydroxylapatite (HAP), magnesium doped HAP, strontium doped HAP, bioglass and medical grade titanium cylinders were implanted into the tibial cortices of New Zealand white rabbits. After 12 weeks, the implants were retrieved for a scanning electron microscopy study coupled with energy dispersive spectroscopy.Following sacrifice and careful retrieval, the samples were dehydrated through a graduated series starting with 50% ethanol and continuing through 60, 70, 80, 90, 95, and 100% ethanol over a period of two days. The samples were embedded in LR White. Again a graduated series was used with solutions of 50, 75 and 100% LR White diluted in ethanol.

Download Full-text

Factors Influencing Electrophysiologic Responsivity in Normal Adults

Journal of Speech and Hearing Research ◽

10.1044/jshr.0804.323 ◽

1965 ◽

Vol 8 (4) ◽

pp. 323-347

Author(s):

Robert Goldstein ◽

Benjamin RosenblÜt

Keyword(s):

Conditioned Stimulus ◽

White Light ◽

Pure Tone ◽

Alpha Rhythm ◽

White Women ◽

White Men ◽

Inverse Relation ◽

Factors Influencing ◽

Electrodermal Responses ◽

Normal Adults

Electrodermal and electroencephalic responsivity to sound and to light was studied in 96 normal-hearing adults in three separate sessions. The subjects were subdivided into equal groups of white men, white women, colored men, and colored women. A 1 000 cps pure tone was the conditioned stimulus in two sessions and white light was used in a third session. Heat was the unconditioned stimulus in all sessions. Previously, an inverse relation had been found in white men between the prominence of alpha rhythm in the EEG and the ease with which electrodermal responses could be elicited. This relation did not hold true for white women. The main purpose of the present study was to answer the following questions: (1) are the previous findings on white subjects applicable to colored subjects? (2) are subjects who are most (or least) responsive electrophysiologically on one day equally responsive (or unresponsive) on another day? and (3) are subjects who are most (or least) responsive to sound equally responsive (or unresponsive) to light? In general, each question was answered affirmatively. Other factors influencing responsivity were also studied.

Download Full-text