2,423 research outputs found

    Integrating Factors that Predict Energy Conservation: The Theory of Planned Behavior and Beliefs about Climate Change

    Get PDF
    A survey of college students was used to examine predictors of four types of energy conservation behavior. Our proposed predictors were derived from Ajzen’s Theory of Planned Behavior (TPB) and from problem awareness variables (environmental concern, and knowledge and beliefs about global warming) thought to have indirect effects on conservation via TPB constructs. TPB constructs were significant direct predictors of target behaviors. Perceived behavioral control (PBC) was the strongest and most consistent predictor, predicting all four behaviors, followed by perceived worth (attitude), predicting three behaviors. TPB variables mediated the effects of either environmental concern or beliefs about the consequences of global warming on three behaviors. Finally, there were also significant mediating relationships among TPB variables themselves. Subjective norm predicted perceived worth and PBC, and perceived worth predicted PBC for all but one behavior. Theoretical implications and implications for intervention are discussed. To our knowledge this is the first study to separately demonstrate, in one sample, the predictive value of TPB with respect to different types of energy conservation, and to integrate TPB variables with climate-change beliefs

    Peregrine Falcon Survey, West Greenland, 1972

    Get PDF
    ... The main purpose of the 1972 survey was to study a sample area of West Greenland to supply baseline data about peregrine falcons from which future surveys could determine the status and trends of this bird in Greenland. The main part of the study had as its goals: 1) to determine the density, distribution, and reproductive success of nesting peregrines in a sample area; 2) to band all peregrine nestlings found; 3) to determine prey species of the peregrine; 4) to make interspecific observations of peregrines and gyrfalcons; 5) to make detailed observations from a blind of a sample peregrine falcon eyrie; 6) to conduct a small-bird census in the area of the sample eyrie; 7) to make a photographic record in colour slides and movies of the investigations. ... Eight peregrine falcon eyries and 3 gyrfalcon eyries were found in the survey area. In all, 18 nestlings were found in the 8 peregrine eyries. Of the 8 eyries, 1 had no young, but showed signs of occupancy ... and was defended by an aggressive pair of falcons. Of the other 7 eyries where we found hatched young, 1 had 4 young, 4 had 3 young, and 2 had 1 young bird each. Of the total of 18 nestling peregrines, 13 were banded and 5 were fully-fledged, on the wing, and unable to be caught for banding. Of the peregrine nestlings banded, 9 were males and 4 were females. The number of nestlings (18) in the 8 peregrine eyries gave a production rate of 2.25 per eyrie, or 2.57 if an average is taken of the 7 eyries actually producing young. At 1 eyrie a young falcon was found dead (the eyrie with 4 young). We know that at least 8 of the remaining 17 young fledged successfully, but we are uncertain about the success of the others and cannot therefore make a definite statement on fledging ratio. We estimate, however, that the fledging rate of the peregrines in our survey area was at least 2.00 per producing eyrie. The maximum dimensions of our irregularly-shaped survey area were 39 x 34 miles (63 x 55 km). The estimated area of the survey was about 800 sq. mi. (2,072 sq. km), or about 700 sq. mi. (1,800 sq. km) when the surface area of fiords and lakes is excluded. The nesting density of the active, young-producing peregrine eyries (7) was about 1 pair per 100 sq. mi. (260 sq. km). ... At the 3 gyrfalcon (Falco rusticolus) eyries we found 8 nestlings or fully-fledged young, of which we were able to band 3. Peregrines and gyrfalcons (and a rare white-tailed sea eagle, Haliaetus albicilla) are the only avian predators nesting in southern West Greenland, although ravens (Corvus corax) competed for some nesting cliff sites. We collected remains of prey species and pellets at each falcon eyrie. Addled eggs (2) from 2 peregrine eyries were collected for pesticide analysis. Eggshell fragments for thickness determination were gathered at 5 peregrine eyries. ... Peregrine falcons in West Greenland appear to be in a healthy state as evidenced by a high nesting density (1/100 sq. mi.) and a high production rate (2.25/eyrie), especially in light of the unusually severe conditions in West Greenland during the winter and late spring of 1971-72. We found little interspecific competition for prey species between peregrines and gyrfalcons. The gyrfalcon is already nesting in West Greenland before the peregrines arrive from their winter migration to the south. The gyrfalcons could therefore be expected to be aggressive in defence of their nesting cliffs and thereby occupy optimal cliffs. Despite this, all the peregrines we studied occupied high, sheer, and quite optimal nesting cliffs. Gyrfalcons seemed to prefer a nesting site lower down on a cliff face than peregrines, and both falcons preferred high, sheer cliffs with a southern exposure. Ravens were relegated to lower, less desirable (more accessible) cliffs for nesting. We await pesticide analysis of the peregrine falcon eggs and prey species collected, as well as eggshell thickness determination. Before these facts are determined we can say nothing definite about the status of peregrines in Greenland. Nesting density and production, however, suggest that the status of the peregrine is better in Greenland than in other areas of the north. ..

    The first Frontier Fields cluster: 4.5{\mu}m excess in a z~8 galaxy candidate in Abell 2744

    Full text link
    We present in this letter the first analysis of a z~8 galaxy candidate found in the Hubble and Spitzer imaging data of Abell 2744, as part of the Hubble Frontier Fields legacy program. We applied the most commonly-used methods to select exceptionally high-z galaxies by combining non-detection and color-criteria using seven HST bands. We used GALFIT on IRAC images for fitting and subtracting contamination of bright nearby sources. The physical properties have been inferred from SED-fitting using templates with and without nebular emission. This letter is focussed on the brightest candidate we found (mF160W_{F160W}=26.2) over the 4.9 arcmin2^2 field of view covered by the WFC3. It shows a non-detection in the ACS bands and at 3.6{\mu}m whereas it is clearly detected at 4.5{\mu}m with rather similar depths. This break in the IRAC data could be explained by strong [OIII]+H{\beta} lines at z~8 which contribute to the 4.5{\mu}m photometry. The best photo-z is found at z~8.00.5+0.2^{+0.2}_{-0.5}, although solutions at low-redshift (z~1.9) cannot be completely excluded, but they are strongly disfavoured by the SED-fitting work. The amplification factor is relatively small at {\mu}=1.49±\pm0.02. The Star Formation Rate in this object is ranging from 8 to 60 Mo/yr, the stellar mass is in the order of M_{\star}=(2.5-10) x 109^{9}Mo and the size is r~0.35±\pm0.15 kpc. This object is one of the first z~8 LBG candidates showing a clear break between 3.6{\mu}m and 4.5{\mu}m which is consistent with the IRAC properties of the first spectroscopically confirmed galaxy at a similar redshift. Due to its brightness, the redshift of this object could potentially be confirmed by near infrared spectroscopy with current 8-10m telescopes. The nature of this candidate will be revealed in the coming months with the arrival of new ACS and Spitzer data, increasing the depth at optical and near-IR wavelengths.Comment: 4 pages, 2 figures, Accepted for publication in Astronomy and Astrophysics Letter

    Probing Bottom-up Processing with Multistable Images

    Get PDF
    The selection of fixation targets involves a combination of top-down and bottom-up processing. The role of bottom-up processing can be enhanced by using multistable stimuli because their constantly changing appearance seems to depend predominantly on stimulusdriven factors. We used this approach to investigate whether visual processing models based on V1 need to be extended to incorporate specific computations attributed to V4. Eye movements of 8 subjects were recorded during free viewing of the Marroquin pattern in which illusory circles appear and disappear. Fixations were concentrated on features arranged in concentric rings within the pattern. Comparison with simulated fixation data demonstrated that the saliency of these features can be predicted with appropriate weighting of lateral connections in existing V1 models

    PINK1 Is Selectively Stabilized on Impaired Mitochondria to Activate Parkin

    Get PDF
    Mutations in PINK1 or Parkin lead to familial parkinsonism. The authors suggest that PINK1 and Parkin form a pathway that senses damaged mitochondria and selectively targets them for degradation

    Binding Mechanism of Metal⋅NTP Substrates and Stringent-Response Alarmones to Bacterial DnaG-Type Primases

    Get PDF
    SummaryPrimases are DNA-dependent RNA polymerases found in all cellular organisms. In bacteria, primer synthesis is carried out by DnaG, an essential enzyme that serves as a key component of DNA replication initiation, progression, and restart. How DnaG associates with nucleotide substrates and how certain naturally prevalent nucleotide analogs impair DnaG function are unknown. We have examined one of the earliest stages in primer synthesis and its control by solving crystal structures of the S. aureus DnaG catalytic core bound to metal ion cofactors and either individual nucleoside triphosphates or the nucleotidyl alarmones, pppGpp and ppGpp. These structures, together with both biochemical analyses and comparative studies of enzymes that use the same catalytic fold as DnaG, pinpoint the predominant nucleotide-binding site of DnaG and explain how the induction of the stringent response in bacteria interferes with primer synthesis

    Recurrence of cervical intraepithelial lesions after thermo-coagulation in HIV-positive and HIV-negative Nigerian women

    Get PDF
    Background: The burden of cervical cancer remains huge globally, more so in sub-Saharan Africa. Effectiveness of screening, rates of recurrence following treatment and factors driving these in Africans have not been sufficiently studied. The purpose of this study therefore was to investigate factors associated with recurrence of cervical intraepithelial lesions following thermo-coagulation in HIV-positive and HIV-negative Nigerian women using Visual Inspection with Acetic Acid (VIA) or Lugol’s Iodine (VILI) for diagnosis. Methods: A retrospective cohort study was conducted, recruiting participants from the cervical cancer “see and treat” program of IHVN. Data from 6 sites collected over a 4-year period was used. Inclusion criteria were: age ≥18 years, baseline HIV status known, VIA or VILI positive and thermo-coagulation done. Logistic regression was performed to examine the proportion of women with recurrence and to examine factors associated with recurrence. Results: Out of 177 women included in study, 67.8 % (120/177) were HIV-positive and 32.2 % (57/177) were HIV-negative. Recurrence occurred in 16.4 % (29/177) of participants; this was 18.3 % (22/120) in HIV-positive women compared to 12.3 % (7/57) in HIV-negative women but this difference was not statistically significant (p-value 0.31). Women aged ≥30 years were much less likely to develop recurrence, adjusted OR = 0.34 (95 % CI = 0.13, 0.92). Among HIV-positive women, CD4 count <200cells/mm3 was associated with recurrence, adjusted OR = 5.47 (95 % CI = 1.24, 24.18). Conclusion: Recurrence of VIA or VILI positive lesions after thermo-coagulation occurs in a significant proportion of women. HIV-positive women with low CD4 counts are at increased risk of recurrent lesions and may be related to immunosuppression
    corecore