Book reviews     

H. H. Lamb  John S. Perry  John A. Eddy 《Climatic change》1980,2(4):409-413

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Representations of mineral chemical analyses in 11-dimensional space part 2, amphiboles     

Kenneth Perry  Jr. 《Lithos》1968,1(4):307-321

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Carbon limitation of sediment bacterial production and denitrification in high nitrate low carbon systems     

Brian D. Grebliunas  William L. Perry 《Environmental Earth Sciences》2016,75(8):662

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Modeling urban leaf area index with AISA+ hyperspectral data     

Ryan R. Jensen  Perry J. Hardin  Matthew Bekker  Derek S. Farnes  Vijay Lulla  Andrew Hardin 《Applied geography (Sevenoaks, England)》2009,29(3):320-332

This study used simple multiple regression to model urban leaf area index (LAI) in Terre Haute, Indiana, USA as a function of AISA+ hyperspectral radiance and its derivative features. Regression R² values ranging from 0.27 to 0.73 were obtained from the various models. Features appearing most frequently in the models included radiance at 0.727, 0.753, 0.848, 0.870, 0.900 and 0.917 μm. The best single predictor of LAI was the absolute difference in radiance between 0.777 and 0.673 μm. The best models performed well at low and intermediate LAI levels, but were less accurate with LAI values between 5.0 and 8.0.  相似文献   

Assessment of non-point sources of fecal pollution in coastal waters of Puerto Rico and Trinidad     

Dave S. Bachoon  Shanu Markand  Garvin Perry 《Marine pollution bulletin》2010,60(7):1117-1121

Traditional and molecular methods (PCR) were used to detect, quantify and identify the source of fecal pollution in coastal sites of Puerto Rico and Trinidad. Enterococci and Escherichia coli standard plate counts were used as a general indicator of fecal contamination while the PCR detection of Bifidobacteria adolescentis and human or bovine specific Bacteroidales were used to examine potential sources. Seven of 14 sites in Trinidad including Maracas Bay which is a major public beach contained significant fecal contamination based on enterococci numbers counts exceeding established thresholds for areas of direct contact. Forty six percent of the 27 stations in Puerto Rico were over the established thresholds for enterococci and 49% according to E. coli counts. About 31% of the stations examined in Puerto Rico had evidence of human derived fecal contamination. Human fecal pollution was detected in only one station from Trinidad. Bovine derived contamination was detected only once.  相似文献   

Corrigendum to “Assessment of non-point sources of fecal pollution in coastal waters of Puerto Rico and Trinidad” [Marine Pollution Bulletin 60 (2010) 1117–1121]     

Dave S. Bachoon  Shanu Markand  Ernesto Otero  Garvin Perry  Adesh Ramsubhag 《Marine pollution bulletin》2010,60(12):2358

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A spatial analysis of neolithic chambered cairns on the island of Arran,Scotland     

Christine M. Perry  Donald A. Davidson 《Geoarchaeology》1987,2(2):121-130

The island of Arran, located to the west of central Scotland, has a dense concentration of Neolithic chambered cairns. The aim of this study is to determine by using a simulation analysis the extent to which thirteen factors influenced the distribution of cairns. Overall, proximity to arable land is shown to be of particular importance but the influence of stream order, coastal type, amplitude of relief, and aspect are also demonstrated to have been of relevance. Since there is little evidence from absolute dating, subdivision of cairns on typological grounds provides the only means for analyzing cairn distributions at three different phases. Results from simulation and cluster analysis indicate variation through time in importance of particular factors. Early cairns are only associated with low relief areas. For cairns of intermediate and later age, the factors as listed above are shown to have been of importance, with proximity to arable land becoming particularly relevant in the last phase. The paper discusses these results in terms of an increasing agricultural component to the Neolithic economy of Arran.  相似文献   

CMEs in the Heliosphere: I. A Statistical Analysis of the Observational Properties of CMEs Detected in the Heliosphere from 2007 to 2017 by STEREO/HI-1     

R. A. Harrison  J. A. Davies  D. Barnes  J. P. Byrne  C. H. Perry  V. Bothmer  J. P. Eastwood  P. T. Gallagher  E. K. J. Kilpua  C. Möstl  L. Rodriguez  A. P. Rouillard  D. Odstrčil 《Solar physics》2018,293(5):77

We present a statistical analysis of coronal mass ejections (CMEs) imaged by the Heliospheric Imager (HI) instruments on board NASA’s twin-spacecraft STEREO mission between April 2007 and August 2017 for STEREO-A and between April 2007 and September 2014 for STEREO-B. The analysis exploits a catalogue that was generated within the FP7 HELCATS project. Here, we focus on the observational characteristics of CMEs imaged in the heliosphere by the inner (HI-1) cameras, while following papers will present analyses of CME propagation through the entire HI fields of view. More specifically, in this paper we present distributions of the basic observational parameters – namely occurrence frequency, central position angle (PA) and PA span – derived from nearly 2000 detections of CMEs in the heliosphere by HI-1 on STEREO-A or STEREO-B from the minimum between Solar Cycles 23 and 24 to the maximum of Cycle 24; STEREO-A analysis includes a further 158 CME detections from the descending phase of Cycle 24, by which time communication with STEREO-B had been lost. We compare heliospheric CME characteristics with properties of CMEs observed at coronal altitudes, and with sunspot number. As expected, heliospheric CME rates correlate with sunspot number, and are not inconsistent with coronal rates once instrumental factors/differences in cataloguing philosophy are considered. As well as being more abundant, heliospheric CMEs, like their coronal counterparts, tend to be wider during solar maximum. Our results confirm previous coronagraph analyses suggesting that CME launch sites do not simply migrate to higher latitudes with increasing solar activity. At solar minimum, CMEs tend to be launched from equatorial latitudes, while at maximum, CMEs appear to be launched over a much wider latitude range; this has implications for understanding the CME/solar source association. Our analysis provides some supporting evidence for the systematic dragging of CMEs to lower latitude as they propagate outwards.  相似文献   

Molecular models of alginic acid: Interactions with calcium ions and calcite surfaces     

Thomas D. Perry IV  Randall T. Cygan 《Geochimica et cosmochimica acta》2006,70(14):3508-3532

Cation binding by polysaccharides is observed in many environments and is important for predictive environmental modeling, and numerous industrial and food technology applications. The complexities of these cation-organic interactions are well suited for predictive molecular modeling and the analysis of conformation and configuration of polysaccharides and their influence on cation binding. In this study, alginic acid was chosen as a model polymer system and representative disaccharide and polysaccharide subunits were developed. Molecular dynamics simulation of the torsion angles of the ether linkage between various monomeric subunits identified local and global energy minima for selected disaccharides. The simulations indicate stable disaccharide configurations and a common global energy minimum for all disaccharide models at Φ = 274 ± 7°, Ψ = 227 ± 5°, where Φ and Ψ are the torsion angles about the ether linkage. The ability of disaccharide subunits to bind calcium ions and to associate with the surface of calcite was also investigated. Molecular models of disaccharide interactions with calcite provide binding energy differences for conformations that are related to the proximity and residence densities of the electron-donating moieties with calcium ions on the calcite surface, which are controlled, in part, by the torsion of the ether linkage between monosaccharide units. Dynamically optimized configurations for polymer alginate models with calcium ions were also derived.  相似文献   

Projected Reorganization of Florida Bay Seagrass Communities in Response to the Increased Freshwater Inflow of Everglades Restoration     

Darrell Anthony Herbert  William B. Perry  Bernard J. Cosby  James W. Fourqurean 《Estuaries and Coasts》2011,34(5):973-992

Historic changes in water-use management in the Florida Everglades have caused the quantity of freshwater inflow to Florida Bay to decline by approximately 60% while altering its timing and spatial distribution. Two consequences have been (1) increased salinity throughout the bay, including occurrences of hypersalinity, coupled with a decrease in salinity variability, and (2) change in benthic habitat structure. Restoration goals have been proposed to return the salinity climates (salinity and its variability) of Florida Bay to more estuarine conditions through changes in upstream water management, thereby returning seagrass species cover to a more historic state. To assess the potential for meeting those goals, we used two modeling approaches and long-term monitoring data. First, we applied the hydrological mass balance model FATHOM to predict salinity climate changes in sub-basins throughout the bay in response to a broad range of freshwater inflow from the Everglades. Second, because seagrass species exhibit different sensitivities to salinity climates, we used the FATHOM-modeled salinity climates as input to a statistical discriminant function model that associates eight seagrass community types with water quality variables including salinity, salinity variability, total organic carbon, total phosphorus, nitrate, and ammonium, as well as sediment depth and light reaching the benthos. Salinity climates in the western sub-basins bordering the Gulf of Mexico were insensitive to even the largest (5-fold) modeled increases in freshwater inflow. However, the north, northeastern, and eastern sub-basins were highly sensitive to freshwater inflow and responded to comparatively small increases with decreased salinity and increased salinity variability. The discriminant function model predicted increased occurrences of Halodule wrightii communities and decreased occurrences of Thalassia testudinum communities in response to the more estuarine salinity climates. The shift in community composition represents a return to the historically observed state and suggests that restoration goals for Florida Bay can be achieved through restoration of freshwater inflow from the Everglades.  相似文献