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Rudd’s Lark Heteromirafra ruddi is a globally threatened species endemic to eastern South Africa’s highland grasslands, where climate envelope modelling has predicted a dramatic reduction in its already small and fragmented distribution. Here we assess recent changes in one of its last strongholds, the Wakkerstroom grasslands. We assessed changes in Rudd’s Lark population and habitat condition over 12 years, within a core section of an area intensively surveyed in 2002–2004. Our 2016 survey found lower absolute numbers of Rudd’s Larks (five transects with Rudd’s Lark present compared to nine in 2002; nine individuals compared to 32), as well as a lower probability of encounter. Transects with shorter grass and higher altitude had a higher probability of Rudd’s Larks occurrence, consistent with findings in 2002. Point locations where Rudd’s Larks were recorded had shorter grass, higher forb cover and more bare ground cover, and tended to be at higher altitudes than random locations in the surrounding grassland. Remotely-sensed fire data showed that late-season fires, which pose a threat to Rudd’s Lark nestling survival, are generally uncommon. Field observations indicated that seven transects (of which two previously contained Rudd’s Lark) that had previously been grassland had been converted to intensive crop production. While Rudd’s Lark may be affected by direct loss of grassland habitat through conversion to crops, the species has also declined within remaining grassland habitat. The drivers of decline remain unclear but this recent observed local decline of Rudd’s Lark in the immediate Wakkerstroom area supports the species’ recent IUCN uplisting to globally ‘Endangered’, given that its previous downlisting was based on habitat requirements and breeding success from this area.
Important Bird and Biodiversity Areas (IBAs) are sites identified as being globally important for the conservation of bird populations on the basis of an internationally agreed set of criteria. We present the first review of the development and spread of the IBA concept since it was launched by BirdLife International (then ICBP) in 1979 and examine some of the characteristics of the resulting inventory. Over 13,000 global and regional IBAs have so far been identified and documented in terrestrial, freshwater and marine ecosystems in almost all of the world’s countries and territories, making this the largest global network of sites of significance for biodiversity. IBAs have been identified using standardised, data-driven criteria that have been developed and applied at global and regional levels. These criteria capture multiple dimensions of a site’s significance for avian biodiversity and relate to populations of globally threatened species (68.6% of the 10,746 IBAs that meet global criteria), restricted-range species (25.4%), biome-restricted species (27.5%) and congregatory species (50.3%); many global IBAs (52.7%) trigger two or more of these criteria. IBAs range in size from < 1 km2 to over 300,000 km2 and have an approximately log-normal size distribution (median = 125.0 km2, mean = 1,202.6 km2). They cover approximately 6.7% of the terrestrial, 1.6% of the marine and 3.1% of the total surface area of the Earth. The launch in 2016 of the KBA Global Standard, which aims to identify, document and conserve sites that contribute to the global persistence of wider biodiversity, and whose criteria for site identification build on those developed for IBAs, is a logical evolution of the IBA concept. The role of IBAs in conservation planning, policy and practice is reviewed elsewhere. Future technical priorities for the IBA initiative include completion of the global inventory, particularly in the marine environment, keeping the dataset up to date, and improving the systematic monitoring of these sites.
BirdLife International´s Important Bird and Biodiversity Areas (IBA) Programme has identified, documented and mapped over 13,000 sites of international importance for birds. IBAs have been influential with governments, multilateral agreements, businesses and others in: (1) informing governments’ efforts to expand protected area networks (in particular to meet their commitments through the Convention on Biological Diversity); (2) supporting the identification of Ecologically or Biologically Significant Areas (EBSAs) in the marine realm, (3) identifying Wetlands of International Importance under the Ramsar Convention; (4) identifying sites of importance for species under the Convention on Migratory Species and its sister agreements; (5) identifying Special Protected Areas under the EU Birds Directive; (6) applying the environmental safeguards of international finance institutions such as the International Finance Corporation; (7) supporting the private sector to manage environmental risk in its operations; and (8) helping donor organisations like the Critical Ecosystems Partnership Fund (CEPF) to prioritise investment in site-based conservation. The identification of IBAs (and IBAs in Danger: the most threatened of these) has also triggered conservation and management actions at site level, most notably by civil society organisations and local conservation groups. IBA data have therefore been widely used by stakeholders at different levels to help conserve a network of sites essential to maintaining the populations and habitats of birds as well as other biodiversity. The experience of IBA identification and conservation is shaping the design and implementation of the recently launched Key Biodiversity Areas (KBA) Partnership and programme, as IBAs form a core part of the KBA network.
Growing concern about the biodiversity crisis has led to a proliferation of conservation responses, but with wide variation between countries in the levels of engagement and investment. Much of this variation is inevitably attributed to differences between nations in wealth. However, the relationship between environmentalism and wealth is complex and it is increasingly apparent that other factors are also involved. We review hypotheses that have been developed to explain variation in broad environmentalism and show that many of the factors that explain such variation in individuals, such as wealth, age and experience, also explain differences between nation states. We then assess the extent to which these factors explain variation between nation states in responses to and investment in the more specific area of biodiversity conservation. Unexpectedly, quality of governance explained substantially more variation in public and state investment in biodiversity conservation than did direct measures of wealth. The results inform assessments of where conservation investments might most profitably be directed in the future and suggest that metrics relating to governance might be of considerable use in conservation planning.
The loss of natural habitats is a major threat to biodiversity, and protected area designation is one of the standard responses to this threat. However, greater understanding of the drivers of habitat loss and of the circumstances under which protected areas succeed or fail is still needed. We use visual assessment of satellite images to quantify land-cover change over periods of up to 30 years in and around a matched sample of protected and unprotected Important Bird and Biodiversity Areas (IBAs) in Africa. We modelled the annual survival of forests and other natural land covers as a function of a range of environmental and anthropic predictors of plausible drivers. The best-supported model indicated that survival rates of natural land cover were highest in steeper areas, at higher altitudes, in areas with lower human population densities and in areas where the cover of natural habitats was already higher at the start of the period. Survival rates of natural land cover in protected areas were, on average, around twice those in unprotected areas, but the differences between them varied along different environmental gradients. The overall survival rates of both protected and unprotected forests were significantly lower than those of other natural land-cover types, but the net benefit of protection, in terms of the absolute difference in rates of loss between protected and unprotected sites, was higher in forests. Interaction terms indicated that as slope and altitude increased, the natural protection offered by topography increasingly nullified the additional benefits of legislative protection. Furthermore, protected area designation offered reduced additional benefits to the survival of natural land cover in areas where rates of conversion were higher at the start of the observation period. Variation in the impacts of protected area status along different environmental gradients indicates that targets to improve the world's protected area network, such as Aichi Target 11 of the Convention on Biological Diversity, need to look beyond simple area-based metrics. Our methods and results contribute to the development of a protocol for prioritizing places where protection is likely to have the greatest effect.
We describe a versatile infrared camera/spectrograph, IRIS, designed and constructed at the Anglo-Australian Observatory for use on the Anglo-Australian Telescope. A variety of optical configurations can be selected under remote control to provide several direct image scales and a few low-resolution spectroscopic formats. Two cross-dispersed transmission echelles are of novel design, as is the use of a modified Bowen-Burch system to provide a fast f/ratio in the widest-field option. The drive electronics includes a choice of readout schemes for versatility, and continuous display when the array is not taking data, to facilitate field acquisition and focusing.
The linearity of the detector has been studied in detail. Although outwardly good, slight nonlinearities prevent removal of fixed-pattern noise from the data without application of a cubic linearising function.
Specific control and data-reduction software has been written. We describe also a scanning mode developed for spectroscopic imaging.
After more than a decade's impressive achievement in the “new” social history and the “new” political history, two distinct though related problems require us to reconsider the data appropriate to these inquiries. First, recent commentators (Foner, 1974; Formi-sano, 1976) have pointed to the relative failure of research in these areas to converge, a failure made more obvious in the light of the programmatic optimism of the 1960s which held out the prospect of an integrated approach to the social basis of politics and to the political implications of social structure. Second, there has been in recent years some acknowledgment by historians (see below) of the vexing question of inferences across levels of data, a matter central to other social sciences and particularly pressing for historians of electoral behavior.
Following a recent assessment of the distribution and habitat use of Gurney’s Pitta in Myanmar (Burma), further extensive surveys were undertaken in 2010, 2011 and 2012. These have extended the species’ known altitudinal limit to between 250 m and 300 m asl and its latitudinal limit to above 12.5°N, around 80 km north of the northernmost historical record, although the species was recorded far less frequently at higher altitudes and latitudes. Birds were recorded in a range of forested habitats, from intact primary forest to secondary and bamboo forest, with no significant difference between major forest types in the likelihood of occurrence. Niche envelope modelling (MaxEnt) suggested a total range size in Myanmar of 3,379 km2, and did not identify any potentially suitable areas in adjacent parts of Thailand. The species’ preference for warmer, wetter areas on flat ground, conditions ideal for growing oil palm and rubber, suggest that its distribution is likely to contract in the near future. The entire range of Gurney’s Pitta in Myanmar falls within the part of the country most suitable for commercial oil palm production, although the projected yields within its range are low to moderate. Field surveys found evidence of rapid recent deforestation and high levels of hunting and trapping in many parts of the region. The species’ range in Myanmar does not overlap with any protected areas. The protection of southern Myanmar’s biodiversity will require substantial investment by foreign conservation interests, sympathetic land-use planning and the strengthening of environment legislation. Protection of extensive tracts of lowland forest within the range of Gurney’s Pitta, particularly the proposed Lenya National Park and the adjacent Ngawun and Htaung Pru Reserve Forests, is urgently needed. Conserving these areas will also protect populations of other globally threatened bird and mammal species.
We conducted an investigation after identifying a cluster of 4 serious infections following transrectal ultrasound–guided biopsy of the prostate (TRUBP) during a 2-month period.
veterans Affairs medical center.
Patients with urinary tract infection (UTI) after TRUBP and time-matched controls with no evidence of infection.
The incidence of UTI within 30 days after TRUBP was calculated from 2002 through 2010. We evaluated the correlation between infection with fluoroquinolone-resistant gram-negative bacilli (GNB) and fluoroquinolone resistance in outpatient Escherichia coli urinary isolates and performed a case-control study to determine risk factors for infection with fluoroquinolone-resistant GNB. Processes for TRUBP prophylaxis, procedures, and equipment sterilization were reviewed.
An outbreak of UTI due to fluoroquinolone-resistant E. coli after TRUBP began 2 years before the cluster was identified and was correlated with increasing fluoroquinolone resistance in outpatient E. coli. No deficiencies were identified in equipment processing or biopsy procedures. Fluoroquinolone-resistant E. coli UTI after TRUBP was independently associated with prior infection with fluoroquinolone-resistant GNB (adjusted odds ratio, 20.8; P = .005). A prediction rule including prior UTI, hospitalization in the past year, and previous infection with fluoroquinolone-resistant GNB identified only 17 (49%) of 35 cases.
The outbreak of fluoroquinolone-resistant E. coli infections after TRUBP closely paralleled rising rates of fluoroquinolone resistance among outpatient E. coli isolates. The delayed detection of the outbreak and the absence of sensitive predictors of infection suggest that active surveillance for infection after TRUBP is necessary in the context of increasing fluoroquinolone resistance in the United States.
In many base-station applications, the load/usage fluctuates over time periods of hours to days, thereby varying the required transmit power by as much as 10 dB. It is desirable to maintain high efficiency and linearity in the power amplifier under these back-off conditions in order to achieve high long-term efficiency. This paper demonstrates a scalable digital predistortion (DPD) approach that can be applied under different power back-off levels in envelope-tracking (ET) amplifiers and quantifies the associated efficiency. Efficiency comparisons are made with other amplifier configurations such as Class B and Doherty. Efficiency of 60% at full power (35 W average power) and >30% efficiency at 10 dB average power back-off are measured in an ET amplifier with a 7.54 dB peak-to-average ratio (PAPR) single-carrier WCDMA signal while meeting linearity specifications. Long-term base-station usage probability functions are presented. The long-term efficiency of the ET amplifiers is simulated to be greater than that of Class B and Doherty amplifiers.
The cuprate superconductors rapidly degrade in moisture and in the presence of organic compounds. A protection method has been developed with a coating process using sol/gel routes to the low temperature formation of oxide films. In contrast to traditional protective films, amorphous silica films formed from a solution precursors gave excellent protection and caused little degradation of the superconductors.
The protective abilities of the films were assessed by monitoring the degradation of Y1Ba2Cu307-d in the presence of 85% relative humidity at 85 C. Volume magnetic susceptibility, four-point probe resistivity, current density measurements and x-ray diffraction were performed. Without protection, degradation was almost complete within 30 minutes of exposure. With protection, superconducting properties were maintained even after 48 hours of exposure.
Microstructural control is a critical issue in the use of diamond films in a variety of engineering applications. Using a novel, electrostatic-based particle seeding process, we have investigated the deposition of diamond films with varying areal nucleation densities. Depositions were performed at 1.000 Torr in a modified electron cyclotron resonance plasma system. Methyl alcohol was the primary diamond precursor species. SEM and Raman spectroscopy were used to evaluate microstructure and composition characteristics. Comparisons in deposition characteristics were made based on relative nucleation density.
The Critically Endangered Liben Lark (formerly Sidamo Lark) is known only from the Liben Plain of southern Ethiopia, where rapid grassland deterioration is driving the species towards extinction. Fieldwork on the Liben Plain in May 2009 to assess changes in habitat and population since June 2007 recorded a significant deterioration in habitat and decline in numbers. In both 2007 and 2009, birds were associated with areas with greater than average grass cover, and in 2007 with areas of higher grass. However, between 2007 and 2009 there was a significant decline in grass cover and height, a 40% decline in number of birds recorded along repeated transects, and a contraction of 38% in the occupied area of the Liben Plain. Moreover, the cover of bare ground increased more in areas where the species was recorded in 2007 than at random points, suggesting a more rapid degradation of the best sites. There was also a loss to arable agriculture of 8% of the grassland present in 2007. Invading fennel plants increased in number and area on the plain but did not appear to influence the distribution of the lark. An analysis of NDVI showed that grassland deterioration could not be explained by drought, and the most likely explanation is that grassland quality is suffering from overgrazing. Predictive modelling suggests that, apart from a smaller and politically insecure area some 500 km to the north-east near Somalia, there is no suitable habitat for this species elsewhere in the Horn of Africa. As a matter of extreme urgency, cattle exclosures need to be established on the Liben Plain to allow grassland regeneration. This may require the ploughing of land to reduce soil compaction and re-sowing with local grass species. In the longer term, further degradation of the plain should be prevented by, for example, clearing encroaching scrub to increase grassland area and reduce grazing pressure, and by developing sustainable rangeland management practices. These actions have the full and active support of local pastoralists.