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Author(s): K. E. Westaway (corresponding author) [1]; J. Louys [2]; R. Due Awe [3]; M. J. Morwood [4]; G. J. Price [5]; J.-x. Zhao [5]; M. Aubert [6]; R. Joannes-Boyau [...]

In streams, gross primary production (GPP) and ecosystem respiration (ER) (i.e., stream metabolism) control the transport and fate of nutrients and organic carbon and vice versa. The importance of short-term and local factors in driving these processes is well known in the literature. However, little information exists regarding the extent of temporal variability of stream metabolism and how both local physicochemical and broad-scale climatic drivers affect this variability. We used 7 years of field data from an open-canopy headwater stream ecosystem in the southwestern United States to quantify the extent of seasonal and inter-annual variability in stream metabolism (GPP, ER, and net ecosystem production [NEP]) and to assess if temporal variation in these processes was related to the magnitude of snowmelt runoff. In spring, seasonal mean ER (p = 0.025, r 2 = 0.67) and NEP (p = 0.004, r 2 = 0.83) were more strongly related to discharge (Q) than GPP (p = 0.19, r 2 = 0.32), potentially because of an increased influx of nutrients and organic carbon during years with higher snowmelt runoff. There were no strong relationships between seasonal mean GPP and Q , light, temperature, turbidity, and specific conductance (p ≥ 0.27, r 2 ≤ 0.18). Our long-term data revealed unanticipated shifts from autotrophic to heterotrophic status within and across years. However, this variability was not strongly associated with environmental factors at either local (i.e., Q or photosynthetically-active radiation) or global (i.e., El Niño-Southern Oscillation) scales. Previous paradigms hold that local attributes dictated by geographic and landscape positioning (e.g., light and temperature regimes) control the trophic status of streams, but our findings suggest that complex combinations of spatiotemporally-variable factors, such as snow accumulation and melting, and their role in connecting terrestrial and aquatic ecosystems can lead to substantial within-stream variation in autotrophic or heterotrophic status. [ABSTRACT FROM AUTHOR]

Genetic evidence for anatomically modern humans (AMH) out of Africa before 75 thousand years ago (ka) and in island southeast Asia (ISEA) before 60 ka (93-61 ka) predates accepted archaeological records of occupation in the region. Claims that AMH arrived in ISEA before 60 ka (ref. 4) have been supported only by equivocal or non-skeletal evidence. AMH evidence from this period is rare and lacks robust chronologies owing to a lack of direct dating applications, poor preservation and/or excavation strategies and questionable taxonomic identifications. Lida Ajer is a Sumatran Pleistocene cave with a rich rainforest fauna associated with fossil human teeth. The importance of the site is unclear owing to unsupported taxonomic identification of these fossils and uncertainties regarding the age of the deposit, therefore it is rarely considered in models of human dispersal. Here we reinvestigate Lida Ajer to identify the teeth confidently and establish a robust chronology using an integrated dating approach. Using enamel-dentine junction morphology, enamel thickness and comparative morphology, we show that the teeth are unequivocally AMH. Luminescence and uranium-series techniques applied to bone-bearing sediments and speleothems, and coupled uranium-series and electron spin resonance dating of mammalian teeth, place modern humans in Sumatra between 73 and 63 ka. This age is consistent with biostratigraphic estimations, palaeoclimate and sea-level reconstructions, and genetic evidence for a pre-60 ka arrival of AMH into ISEA. Lida Ajer represents, to our knowledge, the earliest evidence of rainforest occupation by AMH, and underscores the importance of reassessing the timing and environmental context of the dispersal of modern humans out of Africa. [ABSTRACT FROM AUTHOR]

The article focuses on the impact of the decision of the U.S. Supreme Court case Federal Trade Commission (FTC) v. Actavis Inc. on the patent holders. Topics discussed include exclusionary rights of patent holders, motivating the parties for reverse payment settlements and promoting pro-competitive from the court's decision. It also discusses the role of incentives in the settlement of the case.

ABSTRACT Natural river-floodplain systems are characterized by their dynamic hydrology and diverse geomorphology resulting in a wide range of habitats that support high fish diversity and production. Various factors (e.g. hydrological dynamics, water quality, and biotic processes) have been proposed to explain fish distribution in large river floodplains, but it is still widely acknowledged that the mechanisms involved may vary in diverse floodplain systems and that they are not fully understood. To determine how flooding dynamics and floodplain geomorphology influence fish species distributions across the Volga-Akhtuba floodplain, Russian Federation, we examined the distributions of eight species with respect to variables reflecting floodplain hydrology and geomorphology. On the basis of fish catches in 40 floodplain water bodies at the end of summer in 2006-2008, we found that frequency of occurrence of most fish species remained stable along the time. The distribution of fish species was strongly influenced by the size and shape of water bodies as well as flood extent. Therefore, the long-term flood variability that drives the geomorphic heterogeneity of the floodplain creates suitable habitats across ranges of fish flow guilds (rheophilic, eurytopic, and limnophilic), resulting in high diversity of the floodplain ichthyofauna. We conclude that this diverse habitat availability is a highly significant factor influencing fish distribution in the Volga-Akhtuba floodplain. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to describe current diabetes education practice and specific interventions and responsibilities of diabetes educators in the United States.Methods: The 2008 National Practice Survey (NPS) instrument consisted of 53 items addressing diabetes education program structure, processes and interventions, outcomes and quality improvement activities, and the chronic care model. The survey was hosted online for American Association of Diabetes Educators (AADE) members. Participants totaled 2447 members, constituting a 25% return rate. Data from the 2008 NPS were analyzed and compared with results from previous surveys.Results: Nearly two-thirds of respondents in 2008 provided diabetes education in a single location, most commonly in a clinical outpatient/managed care setting (39%). Most programs provided comprehensive services. Managers noted that 42% of their programs were either cost/revenue neutral or profitable. Programs varied in types of services, number of patient visits, team member functions, time spent on services, and instructional methods used. At least 50% of managers said their programs report outcome data, and 88% participate in quality/performance improvement activities. Nearly two-thirds of respondents were unfamiliar with the AADE-adopted chronic care model.Conclusions: Many 2008 NPS results concur with those obtained in 2005 through 2007. Areas of variability among programs suggest a need for standardized interventions and practice guidelines. Educators are encouraged to report outcomes to elucidate the contributions of their programs to patient care. AADE can use the results and comparative data obtained from the 2008 survey when developing practice, research, and advocacy activities. [ABSTRACT FROM AUTHOR]