Predictions of global circulation models (GCMs) that account for increasing concentrations of greenhouse gases and aerosols in the atmosphere show that warming in the Arctic will be amplified in ...response to the melting of sea ice and snow cover. There is now conclusive evidence that much of the Arctic has warmed in recent decades. Northern Alaska is one region where significant warming has occurred, especially during winter and spring. We investigate how the changing climate of northern Alaska has influenced the annual cycle of snow cover there and in turn, how changes in snow cover perturb the region's surface radiation budget and temperature regime. The focus is on Barrow, Alaska, for which comprehensive data sets exist. A review of earlier studies that documented a trend toward an earlier disappearance of snow in spring is given. Detection and monitoring activities at Barrow are described, and records of snow disappearance from other sites in the Alaskan Arctic are compared. Correlated variations and trends in the date of final snowmelt (melt date) are found by examining several independent time series. Since the mid‐1960s the melt date in northern Alaska has advanced by ∼;8 days. The advance appears to be a consequence of decreased snowfall in winter, followed by warmer spring conditions. These changes in snowfall and temperature are attributed to variations in regional circulation patterns. In recent decades, there has been a higher frequency of northerly airflow during winter that tends to diminish snowfall over northern Alaska. During spring, however, intrusions of warm moist air from the North Pacific have become more common, and these tend to accelerate the ablation of snow on the North Slope of Alaska. One result of an earlier melt date is an increase in the net surface radiation budget. At Barrow, net radiative forcing can exceed 150 W m−2 on a daily basis immediately following the last day of snowmelt, and as a result of an 8‐day advance in this event, we estimate an increase of ∼2 W m−2 on an annual basis. Our results are in general agreement with earlier analyses suggesting that reductions in snow cover over a large portion of the Arctic on an annual basis have contributed to a warming of the Northern Hemisphere (NH). In addition, the terrestrial ecosystems of the region are very sensitive to snow cover variations. There is growing concern that these perturbations are anthropogenically forced and adapting to these environmental changes will have significant social and economic consequences. While observed decreases in NH snow cover are in broad agreement with GCM simulations, our analyses suggest that internal (or natural) shifts in circulation patterns underlie the observed variations. Continued monitoring and further study is needed to determine whether the earlier disappearance of snow cover in spring in northern Alaska is an indicator of greenhouse‐forced global warming or is a manifestation of a more natural, long‐term cycle of climate change.
Virtual environments are an important aspect of serious games for heritage. However navigable three-dimensional (3D) environments can be costly and resource-intensive to create and for users to run. ...In this paper, we propose an alternative approach using “constrained virtual environments”, which present an environment through a series of reduced fidelity two-dimensional (2D) scenes without exhaustive detail. We describe the development of a constrained virtual environment to replicate a 3D environment from a serious game concerning ancient Mesopotamian history. An exploratory experiment discovered that participants experienced a similar sense of presence in the constrained environment to that of the 3D environment and rated the two games to be of similar quality. Participants were equally likely to pursue further information on the subject matter afterwards and collected more information tokens from within the constrained environment. A subsequent interview with a museum expert explored opportunities for such games to be implemented in museum displays, and based on the experiences and issues encountered, a preliminary set of guidelines was compiled for implementing future constrained virtual environments within serious games for heritage.
In this book, Robert L. Stone follows the sound of steel guitar into the music-driven Pentecostal worship of two related churches: the House of God and the Church of the Living God. A rare outsider ...who has gained the trust of members and musicians inside the church, Stone uses nearly two decades of research, interviews, and fieldwork to tell the story of a vibrant musical tradition that straddles sacred and secular contexts._x000B__x000B_Most often identified with country and western bands, steel guitar is almost unheard of in African American churches--except for the House of God and the Church of the Living God, where it has been part of worship since the 1930s. Sacred Steel traces the tradition through four generations of musicians and in some two hundred churches extending across the country from Florida to California, Michigan to Alabama. Presenting detailed portraits of musical pioneers such as brothers Troman and Willie Eason and contemporary masters such as Chuck Campbell, Glenn Lee, and Robert Randolph, Stone expertly outlines the fundamental tensions between sacred steel musicians and church hierarchy._x000B__x000B_In this thorough analysis of the tradition, Stone explores the function of the music in church meetings and its effect on the congregations. He also examines recent developments such as the growing number of female performers, the commercial appeal of the music, and younger musicians' controversial move of the music from the church to secular contexts.
Two new demosponges, Megaciella pituitosa and Cladocroce toxifera, are described from the Aleutian Islands, fostering our contention that the region is a hotspot of poriferan biodiversity. Seven of ...the thirteen species of Megaciella now known worldwide occur in the Sea of Okhotsk or around the Aleutian Islands. Similarly, five of the sixteen species of Cladocroce known worldwide occur in Alaska. Megaciella pituitosa sp. nov. possesses two categories of choanosomal styles and spicules of different sizes that differentiate it from all known congeners. Cladocroce toxifera sp. nov. differs from all known congeners by possessing toxa and an ectosomal tangential arrangement of oxeas.
Video imagery was examined to quantify seafloor disturbance and damage to corals and sponges relative to fishing practices in the central Aleutian Islands of Alaska. Corals and sponges were ...classified as damaged if they had broken skeletons, missing or broken branches, were torn (i.e. sponges) or detached from the seafloor, or were attached but lying on the seafloor. Disturbance was defined as any alteration to the seafloor or biota caused by fishing gear or natural events. Overall, 14% of corals and 21% of sponges were damaged, and disturbance was widespread and evident on most video transects. The proportion of damaged corals was significantly less (p = 0.003) in areas with little or no bottom trawl fishing versus areas with medium and high intensity bottom trawl fishing. For other gear types, damage was not significantly different among fishing levels. Damage for all corals was 7% in untrawled areas, 7% in low-intensity areas, 14% in medium-intensity areas, and 49% in high-intensity areas. For gorgonians, 5% were damaged in untrawled areas and 23% were damaged in high-intensity areas. For hydrocorals, damage was 10% in untrawled areas and 53% in medium-intensity areas. Hydrocorals were absent from high-intensity areas. About 40% of sea whips were damaged in high-intensity areas versus 1% in other areas. While some protective measures have been implemented to halt the expansion of bottom trawl fishing to unfished areas, the conservation of coral and sponge habitat in fished areas is still of primary concern.
Gorgonians make up the majority of corals in the Aleutian archipelago and provide critical fish habitat in areas of economically important fisheries. The microbial ecology of the deep-sea gorgonian ...corals Paragorgea arborea, Plumarella superba, and Cryogorgia koolsae was examined with culture-based and 16S rRNA gene-based techniques. Six coral colonies (two per species) were collected. Samples from all corals were cultured, and clone libraries were constructed from P. superba and C. koolsae. Cultured bacteria were dominated by the Gammaproteobacteria, especially Vibrionaceae, with other phyla comprising <6% of the isolates. The clone libraries showed dramatically different bacterial communities between corals of the same species collected at different sites, with no clear pattern of conserved bacterial consortia. Two of the clone libraries (one from each coral species) were dominated by Tenericutes, with Alphaproteobacteria dominating the remaining sequences. The other libraries were more diverse and had a more even distribution of bacterial phyla, showing more similarity between genera than within coral species. Here we report the first microbiological characterization of P. arborea, P. superba, and C. koolsae.
Developing product architectures is a key phase in design and development processes. It encompasses the transformation of product function to alternative product layouts. In this paper, we describe a ...new approach for identifying modules for product architectures. We begin by reviewing the terminology and motivation for modular products. The new concepts of a functional basis and time ordered function chains are used to formally derive functional models of products. Then, three heuristic methods for identifying modules from functional models are presented. Using the formal functional decomposition and heuristic methods, modular design can be executed earlier in the product development process, as illustrated by the example of a consumer power-tool product and a larger, complex maintenance device. A database of 70 consumer products is used to verify and confirm the overall modular design approach.
Shortly after publication of Raspailia (Hymeraphiopsis) fruticosa Lehnert & Stone, 2015 Rob Van Soest (pers. communication) noticed that this species name is a junior primary homonym of Raspailia ...fruticosa Dendy, 1887, now accepted as Endectyon fruticosa. According to the ICZN the published species name is unavailable and we now suggest to replace the name with Raspailia (Hymeraphiopsis) septentrionalis (holotype deposited at the Zoologische Staatssammlung München, ZSM 20150392, collection data published in Lehnert & Stone 2015).
Background: Medical school evaluations typically rely on both language-based narrative descriptions and psychometrically converted numeric scores to convey performance to the grading committee. We ...evaluated inter-rater reliability and correlation of numeric versus narrative evaluations for students on their Neurology Clerkship.
Design/Methods: 50 Neurology Clerkship in-training evaluation reports completed by their residents and faculty members at the University of Rochester School of Medicine were dissected into narrative and numeric components. 5 Clerkship grading committee members retrospectively gave new narrative scores (NNS) while blinded to original numeric scores (ONS). We calculated intra-class correlation coefficients (ICC) and their associated confidence intervals for the ONS and the NNS. In addition, we calculated the correlation between ONS and NNS.
Results: The ICC was greater for the NNS (ICC = .88 (95% CI = .70-.94)) than the ONS (ICC = .62 (95% CI = .40-.77)) Pearson correlation coefficient showed that the ONS and NNS were highly correlated (r = .81).
Conclusions: Narrative evaluations converted by a small group of experienced graders are at least as reliable as numeric scoring by individual evaluators. We could allow evaluators to focus their efforts on creating richer narrative of greater value to trainees.
Cold-water corals provide critical habitats for a multitude of marine species, but are understudied relative to tropical corals. Primnoa pacifica is a cold-water coral prevalent throughout Alaskan ...waters, while another species in the genus, Primnoa resedaeformis, is widely distributed in the Atlantic Ocean. This study examined the V4-V5 region of the 16S rRNA gene after amplifying and pyrosequencing bacterial DNA from samples of these species. Key differences between the two species' microbiomes included a robust presence of bacteria belonging to the Chlamydiales order in most of the P. pacifica samples, whereas no more than 2% of any microbial community from P. resedaeformis comprised these bacteria. Microbiomes of P. resedaeformis exhibited higher diversity than those of P. pacifica, and the two species largely clustered separately in a principal coordinate analysis. Comparison of P. resedaeformis microbiomes from samples collected in two submarine canyons revealed a significant difference between locations. This finding mirrored significant genetic differences among the P. resedaeformis from the two canyons based upon population genetic analysis of microsatellite loci. This study presents the first report of microbiomes associated with these two coral species.
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