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Purpose: Removal of zirconia restorations can be challenging and time consuming, requiring dental burs with optimal cutting efficiency to minimize iatrogenic complications. Yet, there are very few burs marketed for this purpose and little evidence of their comparative benefit. This study evaluated one specialized bur and compared its cutting efficiency with three general‐purpose burs (one single use and two multiple uses). Materials and methods: This study was designed to assess the cutting efficiency of 4 burs on a high‐strength zirconia substrate. One of these burs is a multiple‐use bur marketed for high‐strength ceramics (Komet 4ZR), another is a single‐use general‐purpose bur (Piranha 837.012 coarse), and two are multiple‐use general‐purpose burs (Brassler 6837.31.012C coarse and Komet 6837.314.012 coarse). The cutting efficiency of each bur was determined by measuring the time taken to perform serial 2 mm cuts into a block of zirconia. Ten burs in each group were tested with repeated cuts until the time taken for a 2 mm cut was twice that of the first 2 mm cut (50% loss of efficiency). This study was performed under reproducible conditions using a custom‐designed and fabricated rig assembly. Results: The results demonstrated a statistically significant difference in the cutting efficiency between bur types. The single‐use general‐purpose bur (Piranha 837.012) was the most efficient for all cut numbers p <2.2 × 10–16. The performance of all burs decreased with each cut, with cutting efficiency dependent on time point/cut number (p = 0.02). The rate of deterioration varied between burs, but this difference was not sufficient to be statistically significant. Conclusions: This study demonstrated that a single‐use bur is more efficient than 3 multiple‐use burs. The cutting efficiency of a single‐use general‐purpose bur (Piranha 837.012 coarse) on Cerec Zirconia Mono L was statistically superior to that of multiple patient use burs in this study, including one marketed for use on high‐strength ceramics. Because single‐use burs are comparatively inexpensive and require no sterilization, they should be strongly considered for the removal of zirconia restorations. [ABSTRACT FROM AUTHOR]

Protected areas (PAs) aim at safeguarding biodiversity and ecosystem services in the long term. Despite the remarkable growth in area covered by PAs in recent years, biodiversity trends continue to worsen as a result of serious global pressures such as habitat destruction and degradation. One main cause of habitat destruction and degradation is land development that implies the replacement of natural land uses–land covers (LULCs) with artificial ones. Here, we assessed the effectiveness of four PA networks at preventing land development in Spain, a biodiversity‐rich country that has experienced recent rapid environmental transformations, using two models of increased validity: an original model and a biophysically enhanced model. We applied a before–after control–impact (BACI) design whereby absolute artificial area increase (AAI) and relative artificial area increase (RAI) were compared across PA categories (nature reserves [NRs], nature parks [NPs], Sites of Community Importance [SCIs], and Special Protection Areas [SPAs]), study zones (coastal and inland), and climates (Atlantic and Mediterranean) using CORINE Land Cover (CLC) data and two control zones: 1‐ and 5‐km buffers around protected polygons. NRs prevented land development, whereas other categories reduced it moderately to very substantially in the assessed period. AAI was especially intense in inland SPAs and NPs. NRs and NPs were the most effective PA categories inland, whereas NRs and SPAs were the most effective ones on the coast. Land development was greater on the Spanish coast than inland inside and outside PAs, especially around Macaronesian and Mediterranean PAs. Atlantic PAs experienced similar or greater land development values than surrounding areas. Our results are intended to guide future conservation efforts in Spain, chiefly on its heavily pressured coastal environment. [ABSTRACT FROM AUTHOR]

1. For biodiversity conservation to be an effective and significant social investment, non-marketed values of biodiversity conservation and its associated opportunity costs should be evaluated in monetary terms. 2. In this study, we measured the willingness to pay (WTP) for bird abundance using a choice experiment (CE) based on the random utility model. We performed a cost-benefit analysis to identify the optimal proportion of broadleaved trees in conifer plantations on a volume basis to maximize the social benefits of bird conservation and wood production. 3. The results suggested that respondents to the CE were not satisfied with their current situation and preferred an increase in bird abundance. However, the estimated WTP indicated diminishing returns of bird conservation. More specifically, WTP first greatly increased before gradually experiencing decreasing marginal values, reaching its peak and finally decreasing slightly with increasing bird abundance. 4. Optimization analyses indicated that when the relationship between bird abundance and broadleaved tree proportion was convex, semi-natural plantations with nonzero broadleaved tree proportion (0-02-0-22) were always optimal options. When the relationship was linear, optimal broadleaved tree proportion ranged from 0 to 0-78 and was greatly affected by wood values. When the relationship was concave, there were only two optimal broadleaved tree proportions: a very high proportion (approximately 0-90) and the lowest possible proportion (0). When the convex and concave relationships approached the linear form, comparable benefits could be attained across broad ranges of broadleaved tree proportion both within and across the relationships. In such cases, it would be useful to increase the likelihood of a feasible land-use strategy of either land sparing or land sharing in order to be successful. 5. Synthesis and applications. It can be difficult to set quantitative targets in biodiversity conservation solely on an ecological basis, and social benefits of biodiversity conservation can create diminishing returns in many situations. The framework we propose shows how to reconcile resource production and biodiversity conservation in the real world. [ABSTRACT FROM AUTHOR]

In this study, wood production and hydrologic functions of forests were accommodated within a planning procedure for separate working circles (areas dedicated to certain forest functions) that were delineated according to an Ecosystem-Based Functional Planning approach. Mixed integer goal programming was used as the optimization technique. The timing and scheduling of a maintenance cutting (partial harvest) was the decision variable in the modeling effort, and an original formulation was developed as a multiobjective planning procedure. Four sample planning strategies were developed and model outputs were evaluated according to these strategies. Spatial characteristics of stands were considered, and used to prohibit the regeneration of adjacent stands during the same time period. Because of the positive relationship between qualified water production and standing timber volume in the forest, the model attempts to maximize qualified water production levels by increasing standing volume stocks in the forest through the delay of regeneration activities. [ABSTRACT FROM AUTHOR]

Attempts to protect and preserve New Zealand's wild and scenic rivers received statutory support in 1981 through amendments to the Water and Soil Conservation Act 1967. These legislative provisions, Water Conservation Orders, were retained in the Resource Management Act 1991, although there was a broadening of the type of waters and range of values that could be protected. An analysis of the 15 water conservation orders granted enabled the identification of a typology that reveals some distinctive geographic and temporal patterns. [ABSTRACT FROM AUTHOR]

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