The participation decision versus the level of participation in an environmental treaty: a spatial probit analysis

2003 ◽  
Vol 87 (2) ◽  
pp. 337-362 ◽  
Author(s):  
James C. Murdoch ◽  
Todd Sandler ◽  
Wim P.M. Vijverberg
2017 ◽  
Vol 110 (1) ◽  
pp. 21
Author(s):  
Odjuvwuederhie Emmanuel INONI ◽  
Patterson Adogbeji EKOKOTU ◽  
David Eduvie IDOGE

<p>Domestic fish production in Nigeria has been growing for the past decade, yet a widening demand-supply gap has persisted leading to a substantial loss in Nigeria’s foreign exchange earnings due to fish imports. In order to boost household food fish supply many individuals have converted available land space within their homestead for catfish production. This study, therefore, investigated the effects of socio-economic variables on the participation in homestead catfish production in the Central Agricultural Zone of Delta State, Nigeria. Using data from 137 respondents engaged in catfish farming, the findings showed a mean age of 44 years for catfish farmers and an average land size of 104.35 m<sup>2</sup> for pond construction. The probit model had a good fit with a Psuedo-<em>R</em><sup>2</sup> of 0.62, 90.5 % of cases correctly predicted, and a significant likelihood ratio (LR) test (<em>p</em> &lt; 0.01). Results of the probit analysis indicated that pond location, age, land area, adults per household, years of education, disposable income, and access to credit exerted a positive and significant effect on homestead catfish production participation decision.</p>


Author(s):  
E. K. Rakhmatullin ◽  
O. D. Sklyarov

The article presents the results of a study of the "Bisolbi" drug toxicity (powder of light ash color, poorly soluble in water). When it is mixed with water it forms a suspension of particles that settle rapidly. Values of acute drug toxicity were determined on rats. We studied groups of six animals of the same sex, as well as similar control ones. The "Bisolbi" drug was injected to white rats intragastrically, males weighing 310 ... 320 g in doses of 2500 and 2740 mg / kg. Each dose was used in six animals; distilled water (3 ml) was used for the controls. The LD50 was calculated by the probit analysis method proposed by Litchfield and Wilcoxon modified by Z. Roth. When administered orally, an atraumatic metal probe was immersed in the stomach. Within 14 days monitored the overall health status and behavior of animals, the manifestation or absence of symptoms of intoxication; noted the features of feed and water ingestion, assessed the condition of the coat, physiological functions. Then groups of experimental rats were euthanized and pathomorphologically examined. We studied the effect of "Bisolbi" with repeated introduction and on not purebred dogs. Two groups of 3-4 years of age were completed with an average initial body weight of 13.63 ... 15.11 kg. Before use, the additive was thoroughly mixed with feed. The drug was injected during 31 days at a dose of 0.5 g / kg. Dogs of the control group (three) were fed wheat flour. After 15 and 31 days in laboratory animals in order to characterize the general condition in the blood, the amount of protein, urea, glucose, creatinine, cholesterol were determined. Based on studies it was found that the drug daily application by animals, is low toxic and safe, does not provoke the development of pathological reactions. According to the Hodge and Sterner classification "Bisolbi" can be attributed to the 6th class of toxicity - relatively harmless. Accordingto GOST 12.1.007-76 LD50 of the drug is more than 151 mg / kg, but less than 5000 mg / kg it is the 3rd hazard class (moderately hazardous).


2021 ◽  
Vol 31 (1) ◽  
Author(s):  
Cenk Yucel

Abstract Background The two-spotted spider mite, Tetranychus urticae (Koch) (Acari: Tetranychidae), is a widely distributed plant-feeding pest that causes significant yield losses in a wide range of crops. Newly developed or improved environmentally friendly biocontrol agents serve as an alternative to traditional pest control tools. Experiment of the effects of 2 local fungal isolates of Beauveria bassiana (BGF14 and BCA32) was carried out against T. urticae under laboratory conditions. Results Both tested isolates had lethal effect in a short time after application, and this effect increased as time progressed. BGF14 and BCA32 isolates caused T. urticae mortality rates ranging from 25.88 to 61.92 and 32.36 to 62.03% when applied at the concentrations between 1×105 and 1×108 conidia/ml, respectively. According to the Probit analysis performed on the effect of fungi on T. urticae adults, the LC50 values of BGF14 and BCA32 isolates on the 7th day after inoculation were 2.6×106 and 6.3×104 conidia/ml, respectively, and the LT50 values for both fungi applied at a concentration of 108 conidia/ml were 2.14 and 2.23 days, respectively. Conclusions The 2 isolates of B. bassiana (BGF14 and BCA32) had the potentials to suppress T. urticae population and can be recommended as promising biocontrol agent candidates for control of T. urticae.


Atmosphere ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 566
Author(s):  
Vanya Y. Draganova ◽  
Hiroki Yokose ◽  
Kazuyo Tsuzuki ◽  
Yuki Nabeshima

A summer field study was conducted in two university dormitories in the Tokai region of Central Japan. The study aimed at understanding the correlation between subjective thermal responses as well as whether nationality was affecting the responses. It was observed that nationality significantly affected thermal sensitivity and preference. The occupants’ acceptance for thermal stress was invariably above 90%. Despite the high levels of humidity observed, the multiple regression model showed that only the indoor air temperature was significant for explaining the variability of thermal sensation for both Japanese and non-Japanese students. The highest probability of voting neutral for university students in dormitory buildings in the Tokai region of Japan was estimated within 24~26.5 °C (by probit analysis). Japanese students were more sensitive to their indoor environment as opposed to the international students. The adjusted linear regression coefficient yielded from the room-wise day-wise averages were 0.48/K and 0.35/K for Japanese sensitivity and international sensitivity, respectively. In our study, the Griffiths’ model of estimating comfort temperature (or thermal neutrality) showed weak predictability and notable differences from the actually voted comfort. The neutral and comfort temperature observed and estimated in the study remained invariably below the recommended temperature threshold for Japan in summer leading to believe that that threshold is worth reevaluating.


2013 ◽  
Vol 59 (4) ◽  
pp. 86-96 ◽  
Author(s):  
Iyad Ghanem ◽  
Adnan Audeh ◽  
Amer Abu Alnaser ◽  
Ghaleb Tayoub

Abstract The objective of current study was to determine the chemical constituents and fumigant toxicity of essential oil isolated by hydro-distillation from dry fruit of bitter fennel (Foeniculum vulgare Miller). The chemical composition of the essential oil was assessed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Constituents of the oil were determined as α-pinene (1.6%) and limonene (3.3%), fenchone (27.3%), estragol (3.9%), and (E)-anethole (61.1%). The fumigant toxicity of the essential oil was tested on larvae of the stored product insect Trogoderma granarium Everts. The mortality of larvae was tested at different concentrations ranging from 31.2 to 531.2 μl/l air and at different exposure times (24 and 48 h). Probit analysis showed that LC50 and LC90 following a 48 h-exposure period for essential oil were 38.4 and 84.6 μl/l, respectively. These results showed that the essential oil from F. vulgare may be applicable to the management of populations of stored-product insects.


Water Policy ◽  
2015 ◽  
Vol 18 (3) ◽  
pp. 599-618 ◽  
Author(s):  
Tinoush Jamali Jaghdani ◽  
Bernhard Brümmer

Market-based water allocation systems have the potential to ensure that scarce water will flow to the user who earns the highest marginal value from that water. However, the number of recorded instances where water supply problems are solved by market-based systems remains limited. This study attempts to identify the decisive factors that motivate farmers’ participation in informal spot water markets in the Rafsanjan aquifer in south-eastern Iran. A two-stage random sampling was carried out in a field survey from November 2008 to February 2009. A logit model is used to test the factors affecting farmers’ decisions to buy groundwater from neighbours who share the same pump. The results show that the technological variables contribute substantially to the participation decision. For example, a decrease in water quality, an increase in the age of the garden, and an increase in the size of the water quota reduce the probability of participation. In contrast, more scattered plots, a higher water flow level from pumping, and a deeper well increase the probability of participation in water markets. Finally, the results suggest that in this area, the participation in water markets is motivated more by profit increasing factors than by farmer socioeconomic characteristics.


Biometrika ◽  
1948 ◽  
Vol 35 (1-2) ◽  
pp. 191-201 ◽  
Author(s):  
D. J. FINNEY ◽  
W. L. STEVENS
Keyword(s):  

2021 ◽  
Vol 19 (1) ◽  
pp. 139-154
Author(s):  
MA Hossain ◽  
MS Yasmin ◽  
MAA Bachchu ◽  
MA Alim

Botanicals are promising and attractive alternatives for pest management. In the present study, three botanical oils namely neem (Azadirachta indica), karanja (Pongamia pinnata) and mehogony (Swietenia mahagoni) were tested against the nymphs of Aphis craccivora Koch to evaluate the toxic and repellent effects under laboratory conditions (25 ± 5oC, 65-75% RH). Four concentrations (0.5, 1.0, 1.5, and 2.0%) along with control were maintained with distilled water and tween-20 was used as emulsifier. Leaf dipped method were used for insect bioassay. Insect mortality was recorded at 24, 48 and 72 hours after intervals while repellency was carried out at 2 hours after intervals upto 10th hours and the collected data were analyzed through MSTAT-C program. Results indicated that all the tested oils had toxic and repellent effects against the A. craccivora nymphs. Among the tested botanical oils, no significant difference was observed in terms of mortality over treatment time. But significant difference was noticed over level of concentrations exerted by the botanical oils. The average highest mortality (28.62%) was recorded by the application of mehogony oil whereas neem oil showed the lowest mortality (27.21%) against the A. craccivora and the mortality was directly proportional to the level of concentrations and hour after treatment (HAT). Probit analysis showed the lowest LD50 values of mehogony oil which revealed the highest toxic effect against the nymph of bean aphid. The highest repellent effect (77.33%) was found in mehogony oil (repellent class IV) among all the botanical oils applied. On the contrary, neem (57.33%) and karanja (55.00%) oils belonged to the same repellent class that is repellent class II. Although all the tested botanical oils evaluated showed toxic and repellent effects but mehogony oil performed as the best potent oil against the nymphs. We therefore suggested using the mehogony oil for the management of bean aphid. SAARC J. Agric., 19(1): 139-154 (2021)


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