scholarly journals Interpreting Life-History Traits of Miconia (Miconia calvescens) through Management over Space and Time in the East Maui Watershed, Hawaii (USA)

2018 ◽  
Vol 11 (4) ◽  
pp. 191-200 ◽  
Author(s):  
James Leary ◽  
Brooke Mahnken ◽  
Christopher Wada ◽  
Kimberly Burnett
Keyword(s):  
Life History Traits ◽  
Cost Effective ◽  
Recruitment Rate ◽  
Ecosystem Functions ◽  
Variable Cost ◽  
Data Set ◽  
Propagule Bank ◽  
Miconia Calvescens ◽  
Cost Effective Alternative

AbstractMiconia (Miconia calvescens DC) was introduced to the East Maui Watershed (EMW) a half-century ago with more than 25 yr of management recorded. Using a historical spatiotemporal data set, we constructed a leptokurtic dispersal kernel with 99% of progeny confined to within 549 m of the nearest maternal source and the remaining 1% dispersed out to 1,636 m. Seedbank persistence, based on postdated recruitment, displayed an exponential decay projecting extinction beyond 20 yr. These parameters are highly congruent to independent interpretations of M. calvescens in Australia and Tahiti. In a simulated stage matrix model, we projected management efforts to locally eradicate a small incipient propagule bank wherein optimal management was achieved with an annual harvest rate that eliminated all juvenile recruits before reaching maturity, until extinction. Based on current pricing for helicopter herbicide ballistic technology (HBT) operations, the optimal, variable cost to locally eradicate this incipient propagule bank was estimated to be less than US$42,000, with ~90% of the effort searching for the most distant 1% of the progeny expended within the first 9 yr after the mature discovery. This variable cost was sensitive to seedbank size, recruitment rate, and dispersal range, but was most sensitive to harvest rates between suboptimal and excess. In a scenario prioritizing the upper region of EMW, we retroactively analyzed past HBT efforts eliminating satellite M. calvescens and determined that 27% of the total effort resulted in 87% of the total protection to this priority asset, with every US$1 invested potentially avoiding US$184 in future costs. Management outside the priority area was less economical, with returns in protection diminishing with distance from the priority upper region. Miconia calvescens is currently not eradicable in the EMW, and full containment of the invasion would require a substantial increase in stable, long-term funding. With limited resources, local eradication of satellite M. calvescens could be the most cost-effective alternative to protecting uninvaded areas prioritized for critical ecosystem functions.

Settlement and Sea-Levels on the Central Coast of British Columbia: Evidence from Shell Midden Cores

2000 ◽  
Vol 65 (1) ◽  
pp. 67-77 ◽  
Author(s):  
Aubrey Cannon
Keyword(s):  
British Columbia ◽  
High Tide ◽  
Cost Effective ◽  
Shell Midden ◽  
Central Coast ◽  
Sea Levels ◽  
History Of ◽  
Cost Effective Alternative ◽  
Strong Linear Relationship

AbstractCoring of shell-midden sites provides a regional chronology of site settlement in the Namu vicinity on the central coast of British Columbia. Coring proved an accurate and cost-effective alternative to traditional test-excavation, and its application in only two short field seasons doubled the number of sites tested in this region. The dating of basal cultural deposits from the cores shows initial occupation of sites ranging from 10,000 to 800 B.P. These dates exhibit a strong linear relationship with the current elevation of deposits above average high tide, suggesting that the settlement history of known shell-midden sites in this region is strongly linked to gradual long-term decline in relative sea levels.

23 GASTRIC BYPASS AS REVISION SURGERY FOR FAILED FUNDOPLICATIONS

2021 ◽  
Vol 34 (Supplement_1) ◽  
Author(s):  
Reda Ezz
Keyword(s):  
Revision Surgery ◽  
Laparoscopic Fundoplication ◽  
Revisional Surgery ◽  
Cost Effective ◽  
Recurrent Reflux ◽  
Failed Fundoplication ◽  
Redo Fundoplication ◽  
Bile Gastritis ◽  
Cost Effective Alternative

Abstract   Laparoscopic fundoplication as anti-reflux technique has emerged and widely expanded as a cost effective alternative to life-long medical treatment in patients with gastroesophageal reflux disease (GERD). Long-term success rate ranges from 80–90% with this procedure, but side effects still exist even with experienced surgeons. Patients with a failed anti-reflux procedure are becoming a more common problem nowadays. Although most of these patients can be managed medically, still some of them will require revisional surgery. Methods We presented our experience from January 2015 to June 2019 facing cases of failed fundoplications. 59 cases with failed fundoplication requiring revision were included in the study. Redo fundoplications were decided preoperatively or intraoperatively to be difficult or unsafe to be done for these cases. Revision surgery for these cases was done using either distal gastrectomy and RY gastro-jejunostomy (22 cases) when the hiatal dissection was not feasible or unsafe due to obscure anatomy or Truncal vagotomy and RY gastro-jejunostomy (37 cases) when the hiatal dissection was easy and feasible. Results Laparoscopy was used in 49 cases and was successfully completed in 42cases (%) and 7conversion (%). Improvement of symptoms: Recurrent reflux or dysphagia was noted in 19 cases (32%) and complete disappeared in 26 cases (44%). One case had leak from the GJ and another one got hematemesis. Both cases were managed conservatively. Nine patient (15%) had bile gastritis with abdominal pain. Five patients (8.5%) complained of dumping symptoms. No mortality was recorded. Conclusion RY gastro-jejunostomy for failed fundoplications is a valid, feasible surgical option when redo fundoplication is difficult to be done or if associated with possible or expected complications.

scholarly journals Efficient routes to land conservation given risk of covenant failure

2015 ◽  
Author(s):  
Richard Schuster ◽  
Peter Arcese
Keyword(s):  
Cost Effectiveness ◽  
Cost Effective ◽  
Private Land ◽  
Legal Challenges ◽  
Monitoring And Enforcement ◽  
Cost Effective Alternative ◽  
The Cost ◽  
Conservation Investment ◽  
Term Monitoring

Conservation initiatives to protect valued species communities in human-dominated landscapes face challenges linked to their potential costs. Conservation covenants on private land may represent a cost-effective alternative to land purchase, although many questions on the long-term monitoring and enforcement costs of covenants and the risk of violation or legal challenges remain unquantified. We explore the cost-effectiveness of conservation covenants, defined here as the fraction of the high-biodiversity landscape potentially protected via investment in covenants versus land purchase. We show that covenant violation and dispute rates substantially affect the estimated long-term cost-effectiveness of a covenant versus land purchase strategy. Our results suggest the long-term cost-effectiveness of conservation covenants may outperform land purchase as a strategy to protect biodiversity as long as disputes and legal challenges are low, but point to a critical need for monitoring data to reduce uncertainty and maximize conservation investment cost-effectiveness.

scholarly journals MODELLING AND PREDICTION OF PRECIPITATION AND SOIL MOVEMENT BASED ON ADINSAR

2020 ◽  
Vol V-3-2020 ◽  
pp. 179-184
Author(s):  
C. H. Yang ◽  
A. Müterthies
Keyword(s):  
Cost Effective ◽  
Large Area ◽  
Hydrologic Models ◽  
New Approach ◽  
Soil Movement ◽  
Drainage Rate ◽  
Weather Observations ◽  
Cost Effective Alternative ◽  
Areas Of Interest

Abstract. Evaluating soil movement related to precipitation is needed for geologic and hydrologic applications. In principle, the soil body swells and shrinks depending on soil type, precipitation rate, moisture content, and drainage rate. The precipitations are normally measured at weather stations. Measuring the soil movement by using ground-based sensors and hydrologic models across a large area is costly and time-consuming. Also the weather observations were not fully involved in modelling. A long-term monitoring using remote sensing is a cost-effective alternative. For this purpose, we developed a new approach in this study to model the transformation between precipitation and soil movement. The time-series soil movement over a large area is evaluated by ADInSAR at mm/yr level. As a result, the predictive model can compute the precipitation at a location from its ADInSAR-derived movement, and vice versa. Our test using Sentinel-1 images shows that the prediction accuracy for precipitation is 14 mm (mean error rate 12%) and it amounts 12 mm/yr for soil movement. The accuracies indicate that our modelling is relevant to the reality. We also discuss the influences of different parameters on the modelling. In the future, we will proceed with tests considering other areas of interest, time spans, and image sources. More target points will be analysed in detail. Last but not least, we will work on the applications related to geology and hydrology.

scholarly journals Efficient routes to land conservation given risk of covenant failure

2015 ◽  
Author(s):  
Richard Schuster ◽  
Peter Arcese
Keyword(s):  
Cost Effectiveness ◽  
Cost Effective ◽  
Private Land ◽  
Legal Challenges ◽  
Monitoring And Enforcement ◽  
Cost Effective Alternative ◽  
The Cost ◽  
Conservation Investment ◽  
Term Monitoring

Conservation initiatives to protect valued species communities in human-dominated landscapes face challenges linked to their potential costs. Conservation covenants on private land may represent a cost-effective alternative to land purchase, although many questions on the long-term monitoring and enforcement costs of covenants and the risk of violation or legal challenges remain unquantified. We explore the cost-effectiveness of conservation covenants, defined here as the fraction of the high-biodiversity landscape potentially protected via investment in covenants versus land purchase. We show that covenant violation and dispute rates substantially affect the estimated long-term cost-effectiveness of a covenant versus land purchase strategy. Our results suggest the long-term cost-effectiveness of conservation covenants may outperform land purchase as a strategy to protect biodiversity as long as disputes and legal challenges are low, but point to a critical need for monitoring data to reduce uncertainty and maximize conservation investment cost-effectiveness.

scholarly journals Analytical, morphological, and rheological behavior of sulphur-extended-binder

2016 ◽  
Vol 43 (6) ◽  
pp. 532-541 ◽  
Author(s):  
Abdulgazi Gedik ◽  
Abdullah Hilmi Lav
Keyword(s):  
Cost Effective ◽  
Testing Methods ◽  
Asphalt Production ◽  
Cost Factor ◽  
Bituminous Material ◽  
Alternative Materials ◽  
Cost Effective Alternative ◽  
Short And Long Term ◽  
Prohibitive Cost

Bituminous material is a limited natural resource mainly used in hot mix asphalt production. The high costs coupled with the large amounts required have been forcing pavement engineers to find cost effective alternative materials that can be used as extenders or partial substitutes. This prohibitive cost factor led this paper to focus on the utilization of abundant granular sulphur as an extender for the more expensive bituminous material. In this study, sulphur-extended binders were prepared by using a 50/70 grade bitumen and by increasing the amounts of granular sulphur as an extension up to a maximum 50% by weight. The samples were then exposed to short and long-term aging by performing the rolling thin film oven and pressure aging vessel tests. Aged and virgin samples were then further tested using analytical, rheological, and morphological testing methods. The promising results demonstrate that the sulphur-extended binder not only increases the performance of the neat bitumen, but can also lower overall costs.

Ascertaining the competitiveness of Thai exports to PRC

2017 ◽  
Vol 27 (3) ◽  
pp. 275-299 ◽  
Author(s):  
Pornlapas Suwannarat
Keyword(s):  
Comparative Advantage ◽  
Cost Effective ◽  
Policy Implications ◽  
Chinese Market ◽  
Growth Trend ◽  
Data Set ◽  
Content Type ◽  
Republic Of China ◽  
Chinese Business

Purpose This study aims to fundamentally focus on the comparative advantage measurement and the trend of change in the international competitiveness of five Thai economic products exporting to the People’s Republic of China during the first half of the 2010s via the analysis of the revealed comparative advantage (RCA) index and market share. Design/methodology/approach The RCA index has been computed to show the comparative advantages of the product to a certain extent: whether it is cost-effective to produce that product in a certain location compared to opportunity cost of the resources in producing that product. The data set of number and value of five important export products from Thailand to China during 2010-2013 has been obtained from the Thai Ministry of Commerce and Thai-Chinese Business Information Centre. Findings The study reveals that of these five important economic products, cassava has the highest comparative advantage and continues to have a rapid growth trend, whilst computer equipment and components have been shown to have comparative disadvantage and the lowest comparative advantage index scores. Research limitations/implications Measuring with various sophisticated indices may provide clearer results. Also, according to unavailability of data set, the four-year period may not be able to show the long-term trend of competitiveness. Future studies are encouraged to study in the longer-term period with numerous indices. Practical implications The research also provides policy implications and measures to develop each sector to enhance competitiveness. Originality/value This is the original attempt to use both indices to assess the competitiveness of important Thai exports to the Chinese market.

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