Variability of spring habitat selection by isards (Rupicapra pyrenaica)

1997 ◽  
Vol 75 (12) ◽  
pp. 1955-1965 ◽  
Author(s):  
Dominique Pépin ◽  
Jean Joachim ◽  
Eric Ferrié

We studied the influence of snow cover and habitat heterogeneity on altitudinal distribution, grouping patterns, and habitat selection in the isard or Pyrenean chamois (Rupicapra pyrenaica) in a protected area from the beginning of May to mid-June 1992. Data were recorded from a single vantage point that allowed visual observations to be made over a wide range of elevations. Variations occurred in the spatial extension of groups, with no sightings above 1900 m when snow was abundant at high altitude and only a few sightings below 1700 m when small patches remained at high altitude. During a late heavy snowfall, however, most sightings were made at the middle altitudinal range, where adjoining habitats of steep terrain provided areas of reduced snow depth. The frequency of observations of solitary animals increased slightly and was higher in closed than in open habitats. Both a significant habitat effect and a significant interaction between habitat and time period of observations were found for groups of the average size, ≥ 2 individuals. Montane pastures at low altitude were first selected. Then, when snow melted, this habitat was vacated for 1800- to 2000-m subalpine pastures. Regardless of the time period, the areas dominated by rhododendrons and rocks or scree were systematically avoided. We suggest that in order to gain a better understanding of habitat selection by large ungulates, especially in mountainous areas, short-term variations in environmental heterogeneity be considered.

2021 ◽  
Vol 11 (4) ◽  
pp. 1431
Author(s):  
Sungsik Wang ◽  
Tae Heung Lim ◽  
Kyoungsoo Oh ◽  
Chulhun Seo ◽  
Hosung Choo

This article proposes a method for the prediction of wide range two-dimensional refractivity for synthetic aperture radar (SAR) applications, using an inverse distance weighted (IDW) interpolation of high-altitude radio refractivity data from multiple meteorological observatories. The radio refractivity is extracted from an atmospheric data set of twenty meteorological observatories around the Korean Peninsula along a given altitude. Then, from the sparse refractive data, the two-dimensional regional radio refractivity of the entire Korean Peninsula is derived using the IDW interpolation, in consideration of the curvature of the Earth. The refractivities of the four seasons in 2019 are derived at the locations of seven meteorological observatories within the Korean Peninsula, using the refractivity data from the other nineteen observatories. The atmospheric refractivities on 15 February 2019 are then evaluated across the entire Korean Peninsula, using the atmospheric data collected from the twenty meteorological observatories. We found that the proposed IDW interpolation has the lowest average, the lowest average root-mean-square error (RMSE) of ∇M (gradient of M), and more continuous results than other methods. To compare the resulting IDW refractivity interpolation for airborne SAR applications, all the propagation path losses across Pohang and Heuksando are obtained using the standard atmospheric condition of ∇M = 118 and the observation-based interpolated atmospheric conditions on 15 February 2019. On the terrain surface ranging from 90 km to 190 km, the average path losses in the standard and derived conditions are 179.7 dB and 182.1 dB, respectively. Finally, based on the air-to-ground scenario in the SAR application, two-dimensional illuminated field intensities on the terrain surface are illustrated.


Metals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 548 ◽  
Author(s):  
Leonid Agureev ◽  
Valeriy Kostikov ◽  
Zhanna Eremeeva ◽  
Svetlana Savushkina ◽  
Boris Ivanov ◽  
...  

The article presents the study of alumina nanoparticles’ (nanofibers) concentration effect on the strength properties of pure nickel. The samples were obtained by spark plasma sintering of previously mechanically activated metal powders. The dependence of the grain size and the relative density of compacts on the number of nanofibers was investigated. It was found that with an increase in the concentration of nanofibers, the average size of the matrix particles decreased. The effects of the nanoparticle concentration (0.01–0.1 wt.%) on the elastic modulus and tensile strength were determined for materials at 25 °C, 400 °C, and 750 °C. It was shown that with an increase in the concentration of nanofibers, a 10–40% increase in the elastic modulus and ultimate tensile strength occurred. A comparison of the mechanical properties of nickel in a wide range of temperatures, obtained in this work with materials made by various technologies, is carried out. A description of nanofibers’ mechanisms of influence on the structure and mechanical properties of nickel is given. The possible impact of impurity phases on the properties of nickel is estimated. The tendency of changes in the mechanical properties of nickel, depending on the concentration of nanofibers, is shown.


2000 ◽  
Vol 279 (4) ◽  
pp. H2013-H2016 ◽  
Author(s):  
Yves Allemann ◽  
Claudio Sartori ◽  
Mattia Lepori ◽  
Sébastien Pierre ◽  
Christian Mélot ◽  
...  

Exaggerated hypoxia-induced pulmonary hypertension is a hallmark of high-altitude pulmonary edema (HAPE) and plays a major role in its pathogenesis. Many studies of HAPE have estimated systolic pulmonary arterial pressure (SPAP) with Doppler echocardiography. Whereas at low altitude, Doppler echocardiographic estimation of SPAP correlates closely with its invasive measurement, no such evidence exists for estimations obtained at high altitude, where alterations of blood viscosity may invalidate the simplified Bernoulli equation. We measured SPAP by Doppler echocardiography and invasively in 14 mountaineers prone to HAPE and in 14 mountaineers resistant to this condition at 4,559 m. Mountaineers prone to HAPE had more pronounced pulmonary hypertension (57 ± 12 and 58 ± 10 mmHg for noninvasive and invasive determination, respectively; means ± SD) than subjects resistant to HAPE (37 ± 8 and 37 ± 6 mmHg, respectively), and the values measured in the two groups as a whole covered a wide range of pulmonary arterial pressures (30–83 mmHg). Spearman test showed a highly significant correlation ( r = 0.89, P < 0.0001) between estimated and invasively measured SPAP values. The mean difference between invasively measured and Doppler-estimated SPAP was 0.5 ± 8 mmHg. At high altitude, estimation of SPAP by Doppler echocardiography is an accurate and reproducible method that correlates closely with its invasive measurement.


2012 ◽  
Vol 49 (No. 1) ◽  
pp. 7-11 ◽  
Author(s):  
J. Souček ◽  
I. Hanzlíková ◽  
P. Hutla

In case of pressed composite biofuels production the important part of the production process is the input row materials disintegration. In dependence on disintegrated material properties, disintegration device, grinding stage and technological process there is in practice necessary for disintegration of culm materials 0.5&ndash;7% and of wooden species even 0.75&ndash;10% of total energetical content of material. A wide range of these figures means that in this sphere of raw materials adaptation can be reached relative high savings through correct choice of technological process and device. The authors of the paper have measured energy consumption of fine disintegration of lignocellulose materials in dependence on particles size and moisture. By the realized measurement of different average size of both input and output particles and consequent statistical evaluation was proved the fiducial energy consumption increase at higher stage of disintegration and higher moisture of the input material. All measurements were carried-out for the grinding mill &Scaron;K 300 and the output particles size was limited by the exchange sieves mesh dimension.


2021 ◽  
Author(s):  
Brian J. Carroll ◽  
Amin R. Nehrir ◽  
Susan Kooi ◽  
James Collins ◽  
Rory A. Barton-Grimley ◽  
...  

Abstract. Airborne differential absorption lidar (DIAL) offers a uniquely capable solution to the problem of measuring water vapor (WV) with high precision, accuracy, and resolution throughout the troposphere and lower stratosphere. The High Altitude Lidar Observatory (HALO) airborne WV DIAL was recently developed at NASA Langley Research Center and was first deployed in 2019. It uses four wavelengths at 935 nm to achieve sensitivity over a wide dynamic range, and simultaneously employs 1064 nm backscatter and 532 nm high spectral resolution lidar (HSRL) measurements for aerosol and cloud profiling. A key component of the WV retrieval framework is flexibly trading resolution for precision to achieve optimal data sets for scientific objectives across scales. A technique for retrieving WV in the lowest few hundred meters of the atmosphere using the strong surface return signal is also presented. The five maiden flights of the HALO WV DIAL spanned the tropics through midlatitudes with a wide range of atmospheric conditions, but opportunities for validation were sparse. Comparisons to dropsonde WV profiles were qualitatively in good agreement, though statistical analysis was impossible due to systematic error in the dropsonde measurements. Comparison of HALO to in situ WV measurements onboard the aircraft showed no substantial bias across three orders of magnitude, despite variance (R2 = 0.66) that may be largely attributed to spatiotemporal variability. Precipitable water vapor measurements from the spaceborne sounders AIRS and IASI compared very well to HALO with R2 > 0.96 over ocean and R2 = 0.86 over land.


Author(s):  
Munekazu Motoyama ◽  
Hiroki Iwasaki ◽  
Miyuki Sakakura ◽  
Takayuki Yamamoto ◽  
Yasutoshi Iriyama

Abstract This paper reports the synthesis of monodisperse spherical LiCoO2 particles in a wide range of average diameter using a urea-based-uniform-precipitation method. The average diameter of LiCoO2 particles can be varied from 2 to 14 lm with a uniform size distribution. The effective approach to maintain the size uniformity while changing the average size of LiCoO2 particles is to keep the ratio of [CO(NH2)2] to [CoSO4] at 8 even when the CoSO4 and urea concentrations are changed.


2021 ◽  
Author(s):  
Huijuan Shen ◽  
Yaode Wang ◽  
Liang Cao ◽  
Ying Xie ◽  
Lu Wang ◽  
...  

Abstract The micro-stripe structure was prepared by laser interference induced forward transfer (LIIFT) technique, composed of Ag nano-particles (NPs). The effects of the film thickness with the carbon nano-particles mixed polyimide (CNPs@PI), Ag film thickness, and laser fluence were studied on the transferred micro-stripe structure. The periodic Ag micro-stripe with good resolution was obtained in a wide range of CNPs@PI film thickness from ~ 0.5 μm to ~ 1.0 μm for the Ag thin film ~ 20 nm. The distribution of the Ag NPs composing the micro-stripe was compact. Nevertheless, the average size of the transferred Ag NPs was increased from ~ 41 nm to ~ 197 nm with the change of the Ag donor film from ~ 10 nm to ~ 40 nm. With the increase of the laser fluence from 102 mJ•cm-2 to 306 mJ•cm-2 per-beam, the transferred Ag NPs became aggregative, improving the resolution of the corresponding micro-stripe. Finally, the transferred Ag micro-stripe exhibited the significant surface enhanced Raman scattering (SERS) property for rhodamine B (RhB). While the concentration of the RhB reached 10-10 mol•L-1, the Raman characteristic peaks of the RhB were still observed clearly at 622 cm-1, 1359 cm-1, and 1649 cm-1. These results indicate that the transferred Ag micro-stripe has potential application as a SERS chip in drug and food detection.


Development ◽  
1977 ◽  
Vol 40 (1) ◽  
pp. 143-157
Author(s):  
Paul S. Burgoyne ◽  
Thomas Ducibella

Mouse embryos (8-cell to early blastocyst) were denuded with pronase, and apposed in pairs which represented a wide range of stage combinations. These pairs either formed aggregates which differentiated into double-sized blastocysts, or they failed to aggregate. The 8–16-cell stages would not envelop late morulae/early blastocysts to form layered aggregates. This must mean that as the embryo differentiates into a blastocyst, the outer surface of the trophoblast loses its capacity for supporting cell spreading. The aggregation data also demonstrate that embryos almost completely lose their potential for aggregation at a very discrete stage in development – namely, between 8 and 9 h before blastocoel formation. It is argued that this is the stage at which the zonular tight junctional seal is completed, and that it is this physical barrier which prevents aggregation. It has been argued previously that the zonular tight junctional seal allows the creation of the special microenvironment which is necessary for the determination of the inner cells as inner cell mass. The completion of this seal 8–9 h before it is required for the formation of a blastocoel would provide a suitable time period for this cell determination to occur. The results obtained also relate to the technique of chimera production. Since the aim of this technique is to generate mice with mixed cell populations, it is important that the blastocyst formed following aggregation should have both cell lines present in the inner cell mass. This can best be assured by using relatively late morula stages (75 h post-HCG injection) since these will have already segregated their inner cells, but the incomplete seal will still allow aggregation to take place.


Author(s):  
Kyle N. Kunze ◽  
Aidan Haddad ◽  
Alexander E. White ◽  
Matthew R. Cohn ◽  
Robert F. LaPrade ◽  
...  

AbstractInjuries to the menisci of the knee are common in orthopedic sports medicine. Bibliometric studies can identify the core literature on a topic and help further our collective knowledge for both clinical and educational purposes. The purpose of the current study was to (1) identify and describe the 50 most cited articles in meniscus research over an 80-year time period to capture a wide range of influential articles and (2) identify the “citation classics” and milestone articles related to the meniscus of the knee. The Science Citation Index Expanded subsection of the Web of Science Core Collection was systematically searched for the 50 most cited meniscus articles. Data pertaining to bibliometric and publication characteristics were extracted and reported using descriptive statistics. The top 50 articles were published between the years 1941 and 2014 and collectively cited 13,152 times. The median (interquartile [IQR]) number of total citations per article was 203.5 (167.0–261.8), while the median citation rate was 9.6 (7.4–13.9) citations per year. The most cited article was “Knee joint changes after meniscectomy,” published in 1948. The article with the highest citation rate of 78.4 citations per year was “The long-term consequence of anterior cruciate ligaments and meniscus injuries – osteoarthritis,” published in 2007. The majority of articles were clinical outcome studies (n = 28, 56%). The top 50 most cited meniscus articles represent a compilation of highly influential articles which may augment reading curriculums and provide a strong knowledge base for orthopaedic surgery residents and fellows. The decade with the most articles was the 2000s, representing a recent acceleration in meniscus-based research. This is a level IV, cross-sectional study.


Author(s):  
Jacqueline R. deVries

In this volume’s rich survey of women’s print media in the interwar period, it might be surprising to find a chapter on feminist writing in religious periodicals – that is, if one assumes that Britain’s religious traditions were inhospitable contexts for feminist organising during this time period. But that assumption would not be entirely correct. The Anglican, Catholic, and Jewish communities in Britain – the three traditions explored here – certainly clung to theological and institutional structures that prevented women from moving freely or quickly into leadership roles. But these communities were never homogenous and their members expressed a wide range of attitudes about gender, sexuality, and women’s roles, some of which were highly progressive and found their way into print. The changing social and gender norms of the interwar period were much debated topics in Britain’s religious communities, and through their engagement with religious media, women found ways to influence those debates.


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