scholarly journals Measuring Use Value from Recreation Participation

1992 ◽  
Vol 24 (2) ◽  
pp. 113-119 ◽  
Author(s):  
John C. Whitehead
Keyword(s):  
Natural Resource ◽  
Recreation Demand ◽  
Use Value ◽  
Resource Valuation ◽  
Participation Decision ◽  
Valuation Method ◽  
Use Values ◽  
One Step ◽  
Recreation Participation ◽  
The One

AbstractRecreation demand studies have traditionally utilized a two-step valuation method, estimating conditional recreation participation probabilities and then intensity of use decisions. These two steps of analysis are combined to estimate the use value of natural resource recreation sites. The purpose of this paper is to provide a method by which use value can be estimated solely from the participation decision. The one-step resource valuation method allows estimation of use values from coefficients of the logistic regression recreation participation equation. The benefits of the method are the reduced data and effort required to value natural resource areas.

scholarly journals Measuring Use Value from Recreation Participation: Reply

1994 ◽  
Vol 26 (1) ◽  
pp. 314-315
Author(s):  
John C. Whitehead
Keyword(s):  
Low Cost ◽  
Travel Cost ◽  
Travel Cost Method ◽  
Use Value ◽  
Cost Models ◽  
Step Method ◽  
Order Of Magnitude ◽  
One Step ◽  
Recreation Participation ◽  
The One

In Whitehead (1992), I proposed a one-step method of estimating recreational use values. I appreciate the opportunity to clarify several points made in the original paper and correct some mathematical errors. The criticisms raise three major issues that should be addressed: the theoretical construct of use value, diminishing marginal utility, and empirical specification. Before I address the criticisms I would like to emphasize that the one-step, recreation-participation method is not viewed as superior to the two-step, travel-cost method or any of its extensions. The method is a means of obtaining order of magnitude use-value estimates if the travel-cost method can not be implemented. To re-state one of the conclusions: “The one-step method is a useful, low-cost substitute for two-step travel cost models when research budgets are limited (Whitehead, 1992 p. 118).” This notion was underemphasized in the original paper.

scholarly journals Indirect and Non-use Values of Halda River- A Unique Natural Breeding Ground of Indian Carps in Bangladesh

2015 ◽  
Vol 6 (2) ◽  
pp. 31-36 ◽  
Author(s):  
MH Kabir ◽  
MM Kibria ◽  
MM Hossain
Keyword(s):  
Contingent Valuation Method ◽  
Decision Makers ◽  
Use Value ◽  
Option Value ◽  
Valuation Method ◽  
Use Values ◽  
Natural Breeding ◽  
Economic Worth ◽  
Source Of Information ◽  
Freshwater River

Bangladesh is a Riverine country; however, Halda River is of special interest among them in recent time for being the only tidal freshwater River in the world that serves as a natural spawning ground for major Indian carps. Besides, this River serves some indirect and non-use values. This study aims at estimating the economic worth of the indirect and non-use value of Halda River. Both indirect and non-use values of this River were calculated by using contingent valuation method. The study found that total indirect use value per year from this River was Tk. 29.50 million. We also estimated that total non-use value was Tk. 31.46 million which comprised of bequest value of Tk. 14.85 million and option value of Tk. 16.61 million. The study suggests that this valid source of information should take into consideration for the decision makers in taking projects and programmes aimed at managing this River more wisely in the future.DOI: http://dx.doi.org/10.3329/jesnr.v6i2.22092 J. Environ. Sci. & Natural Resources, 6(2): 31-36 2013

scholarly journals Measuring Use Value from Recreation Participation: Comment

1994 ◽  
Vol 26 (1) ◽  
pp. 311-313 ◽  
Author(s):  
Donald B. K. English ◽  
J. M. Bowker
Keyword(s):  
Natural Resource ◽  
Recent Article ◽  
Travel Cost ◽  
Use Value ◽  
Two Stage ◽  
Economic Surplus ◽  
Cost Approach ◽  
Sample Information ◽  
Recreation Participation ◽  
Resource Site

In a recent article in this Journal, Whitehead (1992) presents a method for estimating annual economic surplus for recreation trips to a natural resource site based on whether an individual participates in recreation at that site. Whitehead proposes his method as an alternative to the traditional two-stage travel cost approach. We contend that Whitehead's method contains two serious problems. The first is theoretical, and results in an overstatement of the value of recreation trips. The second is empirical, and pertains to the likely misspecification of his model in failing to incorporate what we feel is important sample information. We address these issues in order.

Marx, Silk Poems, and the Pretext of Qualities

2020 ◽  
Vol 151 (1) ◽  
pp. 96-126
Author(s):  
Kathryn Crim
Keyword(s):  
The Other ◽  
Use Value ◽  
Working Day ◽  
The One ◽  
Insight Into

Karl Marx’s comments on silk manufacture in “The Working Day” chapter of Capital, volume 1, demonstrate how “quality”—usually associated with “use value”—has been mobilized by capital to naturalize industrialized labor. Putting his insight into conversation with a recent multimedia poetic project, Jen Bervin’s Silk Poems (2016–17), this essay examines the homology between, on the one hand, poetry’s avowed task of fitting form to content and, on the other, the ideology of labor that fits specific bodies to certain materials and tasks.

A Study on the Rearrangement of Dialkyl 1-Aryl-1-hydroxymethylphosphonates to Benzyl Phosphates

2020 ◽  
Vol 24 (4) ◽  
pp. 465-471 ◽  
Author(s):  
Zita Rádai ◽  
Réka Szabó ◽  
Áron Szigetvári ◽  
Nóra Zsuzsa Kiss ◽  
Zoltán Mucsi ◽  
...  
Keyword(s):  
Quantum Chemical ◽  
Room Temperature ◽  
Phase Transfer ◽  
One Pot ◽  
Substrate Dependence ◽  
Triethylbenzylammonium Chloride ◽  
One Step ◽  
The Pudovik Reaction ◽  
The One ◽  
Solid Liquid

The phospha-Brook rearrangement of dialkyl 1-aryl-1-hydroxymethylphosphonates (HPs) to the corresponding benzyl phosphates (BPs) has been elaborated under solid-liquid phase transfer catalytic conditions. The best procedure involved the use of triethylbenzylammonium chloride as the catalyst and Cs2CO3 as the base in acetonitrile as the solvent at room temperature. The substrate dependence of the rearrangement has been studied, and the mechanism of the transformation under discussion was explored by quantum chemical calculations. The key intermediate is an oxaphosphirane. The one-pot version starting with the Pudovik reaction has also been developed. The conditions of this tandem transformation were the same, as those for the one-step HP→BP conversion.

scholarly journals One-Year Clinical Evaluation of the Bonding Effectiveness of a One-Step, Self-Etch Adhesive in Noncarious Cervical Lesion Therapy

2015 ◽  
Vol 2015 ◽  
pp. 1-5 ◽  
Author(s):  
Babacar Faye ◽  
Mouhamed Sarr ◽  
Khaly Bane ◽  
Adjaratou Wakha Aidara ◽  
Seydina Ousmane Niang ◽  
...  
Keyword(s):  
Clinical Performance ◽  
Retention Rate ◽  
Recall Rate ◽  
Acid Etching ◽  
Significant Difference ◽  
Usphs Criteria ◽  
One Step ◽  
One Year ◽  
The One ◽  
Self Etch

This study evaluated the one-year clinical performance of a one-step, self-etch adhesive (Optibond All-in-One, Kerr, CA, USA) combined with a composite (Herculite XRV Ultra, Kerr Hawe, CA, USA) to restore NCCLs with or without prior acid etching. Restorations performed by the same practitioner were evaluated at baseline and after 3, 6, and 12 months using modified USPHS criteria. At 6 months, the recall rate was 100%. The retention rate was 84.2% for restorations with prior acid etching, but statistically significant differences were observed between baseline and 6 months. Without acid etching, the retention rate was 77%, and no statistically significant difference was noted between 3 and 6 months. Marginal integrity (93.7% with and 87.7% without acid etching) and discoloration (95.3% with and 92.9% without acid etching) were scored as Alpha or Bravo, with better results after acid etching. After one year, the recall rate was 58.06%. Loss of pulp vitality, postoperative sensitivity, or secondary caries were not observed. After one year retention rate was of 90.6% and 76.9% with and without acid conditioning. Optibond All-in-One performs at a satisfactory clinical performance level for restoration of NCCLs after 12 months especially after acid etching.

scholarly journals Building up cyclodextrins from scratch – templated enzymatic synthesis of cyclodextrins directly from maltose

2021 ◽  
Author(s):  
Dennis Larsen ◽  
Sophie R. Beeren
Keyword(s):  
Enzymatic Synthesis ◽  
Combinatorial Libraries ◽  
One Step ◽  
The One ◽  
Kinetic Trapping

Template-induced kinetic trapping of specific cyclodextrins in enzyme-mediated dynamic combinatorial libraries of linear and cyclic α-glucans enables the one-step synthesis of cyclodextrins from maltose in water.

scholarly journals Efficient Cryopreservation of Populus tremula by In Vitro-Grown Axillary Buds and Genetic Stability of Recovered Plants

Plants ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 77
Author(s):  
Elena O. Vidyagina ◽  
Nikolay N. Kharchenko ◽  
Konstantin A. Shestibratov
Keyword(s):  
Survival Rate ◽  
Axillary Buds ◽  
Long Term Storage ◽  
Average Survival ◽  
Transgenic Lines ◽  
Ssr Loci ◽  
One Step ◽  
The One

Axillary buds of in vitro microshoots were successfully frozen at –196 °C by the one-step freezing method using the protective vitrification solution 2 (PVS2). Microshoots were taken from 11 transgenic lines and three wild type lines. Influence of different explant pretreatments were analyzed from the point of their influence towards recovery after cryopreservation. It was found out that the use of axillary buds as explants after removal of the apical one increases recovery on average by 8%. The cultivation on growth medium of higher density insignificantly raises the regenerants survival rate. Pretreatment of the osmotic fluid (OF) shows the greatest influence on the survival rate. It leads to the increase in survival rate by 20%. The cryopreservation technology providing regenerants average survival rate of 83% was developed. It was based on the experimental results obtained with explant pretreatment. Incubation time in liquid nitrogen did not affect the explants survival rate after thawing. After six months cryostorage of samples their genetic variability was analyzed. Six variable simple sequence repeat (SSR) loci were used to analyze genotype variability after the freezing-thawing procedure. The microsatellite analysis showed the genetic status identity of plants after cryopreservation and of the original genotypes. The presence of the recombinant gene in the transgenic lines after cryostorage were confirmed so as the interclonal variation in the growth rate under greenhouse conditions. The developed technique is recommended for long-term storage of various breeding and genetically modified lines of aspen plants, as it provides a high percentage of explants survival with no changes in genotype.

scholarly journals Understanding mathematics of Grover’s algorithm

2021 ◽  
Vol 20 (5) ◽  
Author(s):  
Paweł J. Szabłowski
Keyword(s):  
Phase Change ◽  
Unitary Operator ◽  
Mathematical Structure ◽  
Complex Numbers ◽  
Unitary Operators ◽  
Grover’S Algorithm ◽  
Great Probability ◽  
Grover's Algorithm ◽  
One Step ◽  
The One

AbstractWe analyze the mathematical structure of the classical Grover’s algorithm and put it within the framework of linear algebra over the complex numbers. We also generalize it in the sense, that we are seeking not the one ‘chosen’ element (sometimes called a ‘solution’) of the dataset, but a set of m such ‘chosen’ elements (out of $$n>m)$$ n > m ) . Besides, we do not assume that the so-called initial superposition is uniform. We assume also that we have at our disposal an oracle that ‘marks,’ by a suitable phase change $$\varphi $$ φ , all these ‘chosen’ elements. In the first part of the paper, we construct a unique unitary operator that selects all ‘chosen’ elements in one step. The constructed operator is uniquely defined by the numbers $$\varphi $$ φ and $$\alpha $$ α which is a certain function of the coefficients of the initial superposition. Moreover, it is in the form of a composition of two so-called reflections. The result is purely theoretical since the phase change required to reach this heavily depends on $$\alpha $$ α . In the second part, we construct unitary operators having a form of composition of two or more reflections (generalizing the constructed operator) given the set of orthogonal versors. We find properties of these operations, in particular, their compositions. Further, by considering a fixed, ‘convenient’ phase change $$\varphi ,$$ φ , and by sequentially applying the so-constructed operator, we find the number of steps to find these ‘chosen’ elements with great probability. We apply this knowledge to study the generalizations of Grover’s algorithm ($$m=1,\phi =\pi $$ m = 1 , ϕ = π ), which are of the form, the found previously, unitary operators.

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