1,299 research outputs found
Peatlands and plantations in Sumatra, Indonesia : Complex realities for resource governance, rural development and climate change mitigation
Peatlands play a crucial role in Indonesia's economic development, and in its stated goal of reducing greenhouse gas emissions. Improved peatland management - including a national moratorium on the granting of any new conversion licenses - forms a cornerstone of Indonesia's climate change mitigation commitment. At the same time, rapid expansion of the plantation sector is driving wide-scale drainage and conversion of peat swamp ecosystems. The province of Riau, in central Sumatra, finds itself at the crossroads of these conflicting agendas. This essay presents a case study of three islands on Riau's east coast affected by industrial timber plantation concessions. It examines the divergent experiences, perceptions and responses of communities on the islands. A mix of dramatic protests, localised everyday actions and constructive dialogue has succeeded in delaying or perhaps halting one of the concessions, while negotiations and contestation with the other two continue. With the support of regional and national non-governmental organisations and local government, communities are pursuing alternative development strategies, including the cultivation of sago, which requires no peat drainage. While a powerful political economy of state and corporate actors shapes the contours of socio-environmental change, local social movements can alter trajectories of change, promoting incremental improvements and alternative pathways
Invasion Ecology goes to town : from disdain to sympathy
How can one understand the increasing interest in “urban invasions”, or biological invasions in urban environments? We argue that interest in urban invasions echoes a broader evolution in how ecologists view “the city” in relation to “the natural”. Previously stark categorical distinctions between urban and natural, human and wild, city and ecology have foundered. Drawing on conceptual material and an analysis of key texts, we first show how the ecological sciences in general – and then invasion science in particular – previously had a blind spot for cities, despite a number of important historical and continental European exceptions. Then, we document the advent of an urban turn in ecology and, more recently, in invasion ecology, and how this has challenged fundamental concepts about “nativity”, “naturalness”, and human agency in nature. The urban turn necessitates more explicit and direct attention to human roles and judgements. Ecology has moved from contempt (or indifference) for cities, towards interest or even sympathy
Distribution and growth dynamics of invasive goldenrod (Solidago canadensis) in its introduced range in Estonia, and some Australian comparisons
Understanding the distribution and population dynamics of invasive plant species is fundamental to our capacity to appropriately predict and manage plant invasions. The invasion biology of non-native Solidago canadensis in Estonia was investigated for the first time by assessing its distribution patterns and growth dynamics. First, fifty-two peri-urban populations were surveyed, and population location, size, adjacent communities, number of shoots as well as shoot height were recorded. Then, thirty genets were excavated from previously surveyed populations in order to analyze their age and growth traits in the vicinity of Tartu. The majority of S. canadensis populations were small, i.e. occupying less than 50 m2, had 1 to 50 plants per population and were located predominantly on disturbed roadsides. The surveyed populations were young, with the average age of genets estimated to be five years at the time of sampling in 2006. We suggest that S. canadensis is well adapted to a wide range of habitats but predominantly occurs in human-disturbed habitats adjacent to settlements and roads. We found that Solidago canadensis genet age did not affect significantly its growth traits suggesting that growth traits are similar between younger and older genets
The Effect of Hot Gas in WMAP's First Year Data
By cross-correlating templates constructed from the 2 Micron All Sky Survey
(2MASS) Extended Source (XSC) catalogue with WMAP's first year data, we search
for the thermal Sunyaev-Zel'dovich signature induced by hot gas in the local
Universe. Assuming that galaxies trace the distribution of hot gas, we select
regions on the sky with the largest projected density of galaxies. Under
conservative assumptions on the amplitude of foreground residuals, we find a
temperature decrement of -35 7 K ( detection level,
the highest reported so far) in the 26 square degrees of the sky
containing the largest number of galaxies per solid angle. We show that most of
the reported signal is caused by known galaxy clusters which, when convolved
with the average beam of the WMAP W band channel, subtend a typical angular
size of 20--30 arcmins. Finally, after removing from our analyses all pixels
associated with known optical and X-ray galaxy clusters, we still find a tSZ
decrement of -96 37 K in pixels subtending about 0.8 square
degrees on the sky. Most of this signal is coming from five different cluster
candidates in the Zone of Avoidance (ZoA), present in the Clusters In the ZoA
(CIZA) catalogue. We found no evidence that structures less bound than clusters
contribute to the tSZ signal present in the WMAP data.Comment: 10 pages, 4 figures, matches accepted version in ApJ Letter
Farmer-Managed Natural Regeneration Enhances Rural Livelihoods in Dryland West Africa
Declining agricultural productivity, land clearance and climate change are compounding the vulnerability of already marginal rural populations in West Africa. 'Farmer-Managed Natural Regeneration' (FMNR) is an approach to arable land restoration and reforestation that seeks to reconcile sustained food production, conservation of soils and protection of biodiversity. It involves selecting and protecting the most vigorous stems regrowing from live stumps of felled trees, pruning off all other stems, and pollarding the chosen stems to grow into straight trunks. Despite widespread enthusiasm and application of FMNR by environmental management and development projects, to date, no research has provided a measure of the aggregate livelihood impact of community adoption of FMNR. This paper places FMNR in the context of other agroforestry initiatives, then seeks to quantify the value of livelihood outcomes of FMNR. We review published and unpublished evidence about the impacts of FMNR, and present a new case study that addresses gaps in the evidence base. The case study focuses on a FMNR project in the district of Talensi in the semi-arid Upper East Region in Ghana. The case study employs a Social Return on Investment (SROI) analysis, which identifies proxy financial values for non-economic as well as economic benefits. The results demonstrate income and agricultural benefits, but also show that asset creation, increased consumption of wild resources, health improvements and psycho-social benefits created more value in FMNR-adopting households during the period of the study than increases in income and agricultural yields
The Search for the Missing Baryons at Low Redshift
At low redshift, only about one-tenth of the known baryons lie in galaxies or
the hot gas seen in galaxy clusters and groups. Models posit that these
"missing baryons" are in gaseous form in overdense filaments that connect the
much denser virialized groups and clusters. About 30% are cool (<1E5 K) and are
detected in Ly alpha absorption studies, but about half is predicted to lie in
the 1E5-1E7 K regime. Gas is detected in the 2-5E5 K range through OVI
absorption studies (7% of the baryons) and possibly near 1E5 K from broad Ly
absorption (20% of the baryons). Hotter gas (0.5-2E6 K) is detected at zero
redshift by OVII and OVIII K X-ray absorption, and the OVII line strengths seem
to correlate with the Galactic soft X-ray background, so it is probably
produced by Galactic Halo gas, rather than a Local Group medium. There are no
compelling detections of the intergalactic hot gas (0.5-10E6 K) either in
absorption or emission and these upper limits are consistent with theoretical
models. Claimed X-ray absorption lines are not confirmed, while most of the
claims of soft emission are attributable to artifacts of background subtraction
and field-flattening. The missing baryons should become detectable with
moderate improvements in instrumental sensitivity.Comment: To appear in Annual Review of Astronomy and Astrophysics, Vol 45
(Sept 2007) 44 pages, including 11 figure
Twenty Years of Timing SS433
We present observations of the optical ``moving lines'' in spectra of the
Galactic relativistic jet source SS433 spread over a twenty year baseline from
1979 to 1999. The red/blue-shifts of the lines reveal the apparent precession
of the jet axis in SS433, and we present a new determination of the precession
parameters based on these data. We investigate the amplitude and nature of
time- and phase-dependent deviations from the kinematic model for the jet
precession, including an upper limit on any precessional period derivative of
. We also dicuss the implications of these results
for the origins of the relativistic jets in SS433.Comment: 21 pages, including 9 figures. To appear in the Astrophysical Journa
Femoral vs sciatic nerve block to provide analgesia after medial open wedge high tibial osteotomy in the setting of multimodal analgesia: A randomized, controlled, single-blinded trial.
Medial open wedge high tibial osteotomy (MOW HTO) is associated with moderate to severe postoperative pain. The proximal part of the tibia is innervated by branches from the femoral nerve anteriorly and the sciatic nerve posteriorly. There is a paucity of information regarding the optimal peripheral nerve block for postoperative analgesia with minimal impact on motor function. This study tested the hypothesis that a femoral nerve block provides superior analgesia to a sciatic nerve block after MOW HTO in the setting of multimodal analgesia.
Randomized controlled single-blind trial.
Operating room, postoperative recovery area and ward, up to 6 postoperative months.
Fifty patients undergoing MOW HTO.
Interventions were femoral or sciatic nerve block under ultrasound guidance. For each intervention, a total of 100 mg of ropivacaine was injected. Postoperative pain treatment followed a pre-defined protocol with intravenous patient-controlled analgesia of morphine, paracetamol, and ibuprofen.
The primary outcome was intravenous morphine consumption at 24 h postoperatively. Secondary outcomes included rest and dynamic pain scores (on a numeric rating scale out of 10) at 2, 24 and 48 h postoperatively. Functional outcomes included the Short Form-12, Knee injury and Osteoarthritis Outcome Score, and International Knee Documentation Committee (IKDC) scores measured at 6 months postoperatively.
Mean [95% confidence interval] i.v. morphine consumption at 24 postoperative hours were 24 mg [15 mg,33 mg] in the femoral nerve block group and 24 mg [16 mg,32 mg] in the sciatic nerve block group (p = 0.98). There were no significant differences in the secondary outcomes between groups.
This trial failed to demonstrate that a femoral nerve block provides superior analgesia to a sciatic nerve block after MOW HTO under general anesthesia in the setting of multimodal analgesia. There was no significant difference in quality of life and functional outcomes at 6 months postoperatively between groups. Trial registry number:Clinicaltrials.com - NCT05728294; Kofam.ch - SNCTP000003048 | BASEC2018-01774
Investigating the Effects of Daily Inventory Record Inaccuracy in Multichannel Retailing
Inventory record inaccuracy (IRI) challenges multichannel retailers in fulfilling both brick-and-mortar and direct channel demands from their distribution centers. The nature and damaging effects of IRI largely go unnoticed because retailers assume daily IRI remains stable over time within the replenishment cycle. While research shows that a high level of IRI is damaging, in reality the level of IRI can change every day. We posit that daily IRI variation increases the uncertainty in the system to negatively affect inventory and service levels. Our research uses data collected daily from a multichannel retailer to ground a discrete-event simulation experiment. Going beyond testing just the level of IRI, we evaluate daily IRI variation\u27s impact on operating performance. What we find in our empirical data challenges extant assumptions regarding the characteristics of IRI. In addition, our simulation results reveal that daily IRI variation has a paradoxical effect: it increases inventory levels while also decreasing service levels. Moreover, we also reveal that brick-and-mortar and direct channels are impacted differently. Our findings show that assumptions and practices that ignore daily IRI variation need revising. For managers, we demonstrate how periods of multiday counting help assess their daily IRI variation and indicate what the causes may be
OAO-3 end of mission tests report
Twelve engineering type tests were performed on several subsystems and experiment(s) of the OAO 3 spacecraft near its end of mission. The systems tested include: Princeton experiment package (PEP), fine error system guidance, inertial reference unit, star trackers, heat pipes, thermal control coatings, command and data handling, solar array; batteries, and onboard processor/power boost regulator. Generally, the systems performed well for the 8 1/2 years life of OAO 3, although some degradation was noted in the sensitivity of PEP and in the absorptivity of the skin coatings. Battery life was prolonged during the life of the mission in large part by carefully monitoring the charge-discharge cycle with careful attention not to overcharge
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