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Study Of Effects Of Selective Hunting On A Bear Population Through Pva SimulationAgzitemiz, Mehmet Melih 01 October 2008 (has links) (PDF)
Management of big wildlife such as bears can be a difficult task, especially in the face of human-wildlife conflict and demands of the hunting industry. The Brown Bear (Ursus arctos) population at Yusufeli County (Artvin, northeastern Turkey) has recently been the focus of scientific, social and economic concerns. This study population of c. 140 individuals occurs within 800 km2 of forested and alpine land. Legal hunting of male bears was allowed in 2007 after an interval of four years. This study aims to find out through a population viability analysis the level and frequency of trophy hunting this population can tolerate for the next 50 years. A matrix model with six age-classes for each sex was constructed using observed and literature-based parameter values. RAMAS Metapop was used to simulate four different scenarios where numbers of hunted bears and hunting frequency changes.
The model was highly sensitive to maximum growth rate and adult survival. Interval extinction probabilities for the next 50 years ranged between 0% and 26% depending on the scenario. Viable scenarios (with an extinction probability < / 0.05) were only possible with either no trophy hunting or hunting of 4 subadult/adult males and 1 adult female every other year. Legal and illegal hunting jointly impact the bear population in a strong way, and when they occur simultaneously every year, they lead to extinction in the long run. Avoidance of illegal killing and a close supervision of trophy hunting are crucial in the management of this bear population.
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Population Status, Threats And Conservation Approaches For A Highly Threatened Endemic Plant, Centaurea Tchihatcheffii Fisch. & / MeyErguner Baytok, Yasemin 01 October 2008 (has links) (PDF)
Centaurea tchihatcheffii Fisch. & / Mey. is a critically endangered annual endemic
plant found only in Ankara. This study aimed to determine its distributional range,
metapopulation status, the effects of agricultural activities, and assess conservation
options.
Occurrences and population size estimates were carried out by ground surveys.
Two adjacent subpopulations were intensively studied during 2004-2008. Plant and
seed demographic data were collected in the field and by laboratory tests. Field
experiments simulated the effects of agricultural practices. Risks of extinction and
possible impacts of different management actions were investigated through a
population viability analysis (PVA) by constructing a two-stage stochastic model.
Six scenarios involving different management actions were run with 10,000
replications each using RAMAS Metapop.
A total of 14 patchily distributed subpopulations were found to have an extent of
occurrence of > / 700 km2. Herbicide applications caused extreme mortality and
reduced germination success, and were shown to be the major anthropogenic
threat against long-term survival of C. tchihatcheffii. Tillage led to an increase in
density and reproductive success in the following year. PVA simulations for most
scenarios predicted extinction of both subpopulations within 4 to 95 years, but a
conservation management scenario involving delayed tillage ensured viable
populations with a combined size of 21 million individuals.
PVA results demonstrated that timing and frequency of tillage is crucial. Therefore,
we propose tillage to be carried out after seed set every other year for protected
subpopulations to ensure their long term persistence. Alternatively, unprotected
subpopulations elsewhere can benefit from organic or nature-friendly farming.
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Identification Of Demographic Structure And Population Viability Analysis Of Gazella Subgutturosa In SanliurfaCobanoglu, Aziz Emre 01 February 2010 (has links) (PDF)
Goitered gazelle (Gazella subgutturosa) is an Asian antelope species and it is classified as Vulnerable by IUCN. They have an economic, esthetic and cultural value / therefore, they had been hunted and domesticated for a long time. Additional human disturbance over years nearly led goitered gazelle populations in Turkey to extinction. Today in Turkey, only natural population of goitered gazelle lives in Sanlurfa.
In this theses, demographic structure and population parameters of natural population goitered gazelle in Sanliurfa is studied. Line transect and regular surveys are performed to collect data about demographic structure of the population such as sex ratio and group composition. Line transect sampling, which is a distance sampling technique, is used to estimate population size and density of the population. GPS collared goitered gazelles are monitored for fecundity and survival rate.
Data is collected for 18 from July 2008 to December 2009 during 32 field surveys. Four main transect samplings have been performed and including transect samplings that are done during regular surveys, 90 line transects are walked.
Population sizes and densities were estimated to be (average ± / standard error) 242 ± / 184 and 2.302 ± / 1.590 individual per km2 for July 2008 / 365 ± / 179 and 3.476 ± / 1.707 individual per km2 for January 2009 / 319 ± / 111 and 3.039 ± / 1.059 individual per km2 for June 2009 and lastly, 317 ± / 243 and 3.019 ± / 2.315 for November 2009. Survival rate is estimated to be 0.276, 0.540 and 0.585 for calves, 1 year old and 2+ years olds respectivelty, and fecundity is estimated to be 0.4.
This preliminary study shows that according to Population Viability Analysis results, natural goitered gazelle population in Turkey will be extinct in next 10 years if more effective conservation is not performed.
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Evaluation Of The Adaptation Process Of A Reintroduced Anatolian Mouflon (ovis Gmelinii Anatolica) Population Through Studying Its Demography And Spatial EcologyOzut, Deniz 01 April 2010 (has links) (PDF)
In this thesis the demography, home range and habitat selection of a
reintroduced population of Anatolian mouflon (Ovis gmelinii anatolica),
which had a single remaining population, was studied to evaluate the
reintroduction success and determine the conservation management
interventions.
For this purpose among 104 individuals reintroduced in Sariyar
Wildlife Protection Area (Ankara, Turkey), 40 adults were radio-collared
and 28 juvenile were ear-tagged and monitored from 2005 to 2009. The
survival of the population according to the age groups (females, 0: 0.5423,
1: 0.60, 2: 0.5316, 3: 0.6637, 3+: 0.6728) and the fecundity of adult females (2:
0.2260, 3: 0.2034, 3+: 0.2034) are estimated. A population viability analysis
was performed and the persistence of the population within the next 20
years was estimated. Increasing the survival rate of adult female through
conservation or restocking the population with at least six adult females
every year decreased the risk of extinction in the near future considerably.
The year-round home ranges of the individuals ranged between 805
&ndash / 3435 ha. (Mean ± / SE: 1934 ± / 140 ha). The movements of the tracked
individuals followed seasonal patterns: centers of activities changed
according to seasons in 80% of the adult mouflon. Reintroduced mouflon
selected southern aspects (p=0.001), increasing slopes &ndash / especially medium
to high slope terrain &ndash / (slope > / 30° / , p=0.002), and distant locations to
villages and roads.
Results indicate that appropriate protective measures should be
implemented immediately to mitigate the causes of juvenile mortality.
Restocking the population for the next 10 years with adult females would
have a stabilizing effect on the declining population and will act as a
buffering mechanism during the adaptation period to the new area.
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Preparation Of Functional Surfaces Using Zeolite Nanocrystals For Biosensor And Biomedical ApplicationsKirdeciler, Salih Kaan 01 July 2012 (has links) (PDF)
Zeolites are crystalline aluminosilicates which have highly ordered pore structures and high surface area. Also the tailorable surface properties, high ion-exchange capability, high chemical, thermal, and mechanical strength make these particles an important candidate for various application such as sensors, catalysis, dielectric materials, separation, and membrane technologies. Although zeolites have these unique properties, applications where zeolites are integrated into devices according to their application areas, are limited due to the powder form of the material.
The purpose of the current study was to investigate the effect of zeolite nanoparticles on conductometric biosensor performance and cell viability measurements. Firstly, zeolite attachment on silicon surfaces was investigated by attaching silicalite and zeolite A nanoparticles onto the silicon substrates by direct attachment methodology in a closely packed monolayer form with perfect orientation and full coverage without using any chemical linker. Furthermore, the ability to pattern these zeolite crystals on silicon substrates with electron beam lithography and photolithography techniques was investigated. With the combination of electron beam lithography and direct attachment methodology, zeolite patterns were produced with feature sizes as small as a single silicalite nanoparticle thick line, that is approximately 500 nm. This approach has the ability of patterning very small features on silicon substrate, but the drawback is the long patterning time and lack of electron beam stability during long pattern formation process. Accordingly, it is almost impossible to form large patterns with electron beam lithography systems.
Afterwards, to have full control on surfaces with differentiated areas on solid substrates, patterns of one type of zeolite crystals was formed on the monolayer of another type of zeolite layer with electron beam lithography for the first time. The same closed packed and highly oriented silicalite patterns were successfully formed on zeolite A monolayers and vice versa.
Then photolithography technique was combined with direct attachment methodology to overcome the problem of the lack of total patterned area. With this technique, it was possible to pattern the whole silicon wafer in a couple of seconds, however the feature size of the zeolite patterns was limited with the infrastructures of the mask fabricated for photolithography studies. In this particular study, zeolite lines patterns with a minimum of 5 µ / m thickness were prepared and the total patterned area was kept constant at 1 cm2. Similar to what was obtained by electron beam lithography study, zeolite A patterns were formed on silicalite monolayers with the minimum feature size of 5 µ / m and vice versa.
In the second part of the study, zeolite films were prepared on the transducers of conductometric biosensors using dip coating technique and named as Zeolite Coated Transducers (ZCT). Electrodes prepared using a mixture of zeolite and enzyme solution and then subjected to casting using glutaraldehyde were called Zeolite Membrane Transducers (ZMT). The operational and storage stabilities were determined to be in an acceptable range using ZCTs for conductometric urea biosensors. It was observed that using electrodes fabricated by the ZCT technique enhanced the biosensor signals up to two times and showed a rapid response after the addition of urea to the medium when it was compared with Standard Membrane Transducers (SMT). This enhancement can be explained by the lack of GA layer on top of the film, which acts as a diffusion barrier and inhibits the activity of the enzyme. On the second part of this conductometric biosensor study, effect of zeolite modification with methyl viologen (MV) and silver nanoparticles (Ag+ and Ag0), as well as the effect of changing Si/Al ratio was investigated with three different zeolite Beta particles which have Si/Al ratios of 40, 50, and 60. There were no significant effect of MV modification on ZMTs and there was no response observed with Ag+ and Ag0 modified zeolites. However, it was observed that conductometric responses increased with increasing Si/Al ratio for ZMTs. This behavior can be due to an increased hydrophobicity and/or the increasing acidic strength with the increasing Si/Al ratio within the zeolite crystals. Also ZCTs showed higher responses with respect to both SMTs and ZMTs. When compared with SMTs and ZMTs, ZCTs had higher reproducibility due to the controlled thickness of zeolite thin film by dip coating, and the controlled amount of enzyme adsorbed on this film.
In the third part of the study, effect of zeolites on cell proliferation with MG63 osteoblast cells and NIH3T3 fibroblast cells were investigated. For that purpose, zeolite A, silicalite, and calcined forms of these zeolites were patterned with photolithography technique onto silicon wafers. Three different patterns prepared for this particular study, which has 0.125cm2, 0.08825cm2, and 0.04167cm2 zeolite patterned areas on 1 cm2 samples. In that way, not only the zeolite type and effect of calcination of zeolites, but also the effect of zeolite amount on MG63 osteoblast cells and NIH3T3 fibroblast cells were investigated.
Silicalite coated samples were observed to have higher amount of cells than zeolite A coated samples after 24, 48, and 72 hours of incubation. This may be referred to the hydrophilic/hydrophobic properties, surface charge, and/or particle size of zeolites. Also it is observed that higher zeolite amount on samples resulted in an increase in the number of cells attached to the samples.
There was also a significant increase in the number of cells upon using calcined silicalite samples. Accordingly, it can be hypothesized that zeolite pores result in an enhancement of protein adsorption and proliferation, even if this only occurs at the pore openings. On the other hand, there was no positive effect of calcining zeolite A. This result was expected since there is no structure directing agent used in synthesis procedure of zeolite A, which again supports the fact that pores might have some role in cell attachment.
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Development of cryopreservation techniques for early stages zebrafish (Danio rerio) oocytesTsai, Sujune January 2009 (has links)
Cryopreservation of germplasm of aquatic species offers many benefits to the fields of aquaculture, conservation and biomedicine. Although successful fish sperm cryopreservation has been achieved with many species, there has been no report of successful cryopreservation of fish embryos and late stage oocytes which are large, chilling sensitive and have low membrane permeability. In the present study, the sensitivity to chilling and toxicity of cryoprotectants of early stage zebrafish ovarian follicles were studied before designing protocols for their cryopreservation using controlled slow cooling. The effect of cryoprotectant, freezing medium, cooling rate, method for cryoprotectant removal, post-thaw incubation time and ovarian follicle developmental stage were investigated. In vitro culture method for early stage zebrafish ovarian follicles were also developed. The studies showed that stage I and II ovarian follicles are less sensitive to chilling than stage III follicles and methanol was the least toxic cryoprotectant. 4M methanol in potassium chloride (KCl) buffer was found to be the optimal cryoprotective solution and the optimum cooling rate was 4 °C/min for stage I and II follicles. Although the highest survivals after 2 h post-thawed incubation were 50.7 ± 4.0% for stage II ovarian follicles obtained with FDA+PI staining, ADP/ATP ratios of the cryopreserved follicles were significantly increased indicating increased cell death. Furthermore, in vitro culture experiments showed that there was no growth for stage I and II ovarian follicles after cryopreservation, indicating that successful cryopreservation of early stage zebrafish ovarian follicles at liquid nitrogen still remains elusive. From in vitro culture study, 90% L-15 medium at pH 9.0 containing 10 IU/ml hCG was effective for in vitro culture of stage I and II ovarian follicles. Systematic study on cryopreservation of early stage fish ovarian follicles at liquid nitrogen temperature is reported ii here for the first time. The results will provide useful information on the future development of protocol design for successful cryopreservation of early stage fish ovarian follicles.
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The modulating effect of sildenafil on cell viability and on the function of selected pharmacological receptors in cell cultures / B.E. EagarEager, Blenerhassit Edward January 2004 (has links)
Since sildenafil's (Viagra®), a phospodiesterase type 5 (PDE5) inhibitor, approval for the
treatment of male erectile dysfunction (MED) in the United States early 1998, 274
adverse event reports were filed by the Food and Drug Administration (FDA) between 4
Jan. 1998 and 21 Feb. 2001 with sildenafil as the primary suspect of various
neurological disturbances, including amnesia and aggressive behaviour (Milman and
Arnold, 2002). These and other research findings have prompted investigations into the
possible central effects of sildenafil.
The G protein-coupled muscarinic adetylcholine receptors (mAChRs) and serotonergic
receptors (5HT-Rs), have been linked to antidepressant action (Brink et al. 2004).
GPCRs signal through the phosphatidylinositol signal transduction pathway known to
activate protein kinases (PKs). Since the nitric oxide (NO)-guanylyl cyclase signal
transduction pathway is also known to involve the activation of PKs (via cyclic guanosine
monophosphate (cGMP)), the scope is opened for sildenafil to possibly modulate the
action of antidepressants by elevating cGMP levels.
It is generally assumed that excitotoxic delayed cell death is pathologically linked to an
increase in the release of excitatory neurotransmitters e.g. glutamate. Glutamate
antagonists, especially those that block the define NMDA-receptors, are neuroprotective,
showing the importance of the NMDA-NO-cGMP pathway in neuroprotection (Brandt et
al., 2003). Sildenafil may play a role in neuroprotection by elevating cGMP levels.
Aims: The aims of the study were to investigate any neuroprotective properties of
sildenafil, as well as modulating effects of sildenafil pre-treatment on mAChR function.
Methods: Human neuroblastoma SH-SY5Y or human epithelial HeLa cells were seeded
in 24-well plates and pre-treated for 24 hours in serum-free medium with no drug
(control), PDE5 inhibitors sildenafil (100nM and 450 nM), dipiridamole (20 µM) or
zaprinast (20 µM), non-selective PDE inhibitor 3-isobutyl-I-methylxanthine (IBMX -
ImM), cGMP analogue N2,2'-0-dibutyrylguanosine 3'5'-cyclic monophosphate sodium
salt (500 µM), guanylcyclase inhibitor 1H-[1 ,2,4]oxadiazolo[4,3-a]quinoxalin-I-one (ODQ
- 3 µM) or sildenafil + ODQ (450 nM and 3 µM respectively). Thereafter cells were used
to determine mAChR function by constructing dose-response curves of methacholine or
to determine cell viability utilising the Trypan blue, propidium iodide and MTT tests for
cell viability.
Results: Sildenafil pre-treatments induced a 2.5-fold increase in ,the Emax value of
methacholine in neuronal cells but did not show a significant increase in epithelial cells
The Trypan blue test suggests that neither the PDE5 inhibitors nor a cGMP analogue
show any neuroprotection. Rather, sildenafil 450 nM, dipiridamole and IBMX displayed
a neurodegenerative effect. The MTT test was not suitable, since pre-treatment with the
abovementioned drugs inhibited the formation of forrnazan. The propidium iodide assay
could also not be used, due to severe cell loss.
Conclusion: Sildenafil upregulates mAChR function in SH-SY5Y cells and displays a
neurodegenerative, and not a protective property, in neuronal cells. This is not likely to
be associated with its PDE5 inhibitory action, but may possibly be linked to an increase
in cGMP levels via the NO-cGMP pathway. / Thesis (M.Sc. (Pharmacology))--North-West University, Potchefstroom Campus, 2005.
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Evaluation of isolated dorsal root ganglion cells as a model to study neural calcium overload / E.E. JordaanJordaan, Esaias Engelbertus January 2004 (has links)
Background and motivation: The event of neural Ca2+ overload is known to have
several deleterious effects resulting in cell death caused by ischaemia, hypoglycaemia,
hypoxia and several neurodegenerative diseases such as Alzheimer's disease,
Parkinson's disease and AIDS-related dementia. In vitro models for the investigation
of the mechanisms involved in Ca2+ overload include brain slice preparations,
neuronal cultures as well as acutely isolated neurons, mostly from the hippocampus
and cortical brain areas. Additional models for investigating Ca2+ overload may bring
about new knowledge to areas of the phenomenon that are still unresolved.
Methodology: In this study, several theoretical Ca2+ overload-related interventions
were combined aimed at inducing cell death in acutely isolated rat dorsal root ganglia.
To elucidate the mechanism/s involved in the cell death observed following exposure
to this intervention, the effects of several alterations to the intervention's composition
were assessed. This examination was extended by the addition of several recognized
and potential protective compounds to the intervention. Cell death was indicated by
the trypan blue exclusion assay and recorded after 18 hours exposure to the
interventions by counting live and dead neurons under a light microscope.
Results and conclusions: The goal was to evaluate the possible application of dorsal
root ganglia as a model for neural Ca2+ overload outside the brain. Since Ca2+w as
required for cell death to be induced, it is concluded that the observed cell death was
indeed primarily due to Ca2+ overload. Besides extracellular Ca2+, KC1-induced
depolarization was also required for cell death to be induced, while the antagonists did
not demonstrate significant protection against cell death. Based on the results, the
mechanism of Ca2+ overload could not be defined beyond doubt, but the voltage activated
Ca2+ channels are likely to be involved. / Thesis (M.Sc. (Physiology))--North-West University, Potchefstroom Campus, 2005.
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Investigation of the Impact on Yeast Fermentation Performance in Production of Pale Lager Beer through Management Control / Utredning av påverkan på jästfermentering genom hanteringsstyrning vid produktion av ljus lagerölSkogsberg, Zara January 2013 (has links)
Through a full factorial design experiment, the effects of time between worts, wort aeration and yeast dosage in production of a pale lager beer were examined in the beer process at Spendrups Bryggeri AB. The aim was to learn how different parameters may affect the yeast fermentation performance during beer production. Response variables used were the concentrations of ethyl acetate and isoamyl acetate, free amino nitrogen (FAN) degradation and change in extract. A statistical analysis showed that the concentration of ethyl acetate is dependent on yeast dosage and the interaction between time between worts and aeration while the isoamyl acetate concentration is dependent on yeast dosage and time between worts. No parameters are statistically significant for FAN degradation while the change in extract is dependent on the yeast dosage. Due to botched runs, mostly because of aeration problems, it was not possible to verify theoretical parameter values and responses. Since the aeration was not properly performed, the management of the aeration control should be further investigated. Ester analysis and analysis of FAN were performed as worts entered and exited horizontal fermentation tanks. An additional analysis of ester content was also performed as the early stage beer was transferred into lagering tanks. Cell viability as well as extract, pH and tank temperature was measured daily to verify the state of fermentation. Statistical calculations showed that when using NucleoCounter YC-100, there is no significant difference between analysis made of samples homogenized by a magnetic stirrer and samples shaken by hand.
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Mokesčių ir subsidijų įtaka ūkių ekonominiam gyvybingumuui / Influence of Taxes and Subsidies on the Economic Viability of FarmsŠinkūnaitė, Ingrida 21 June 2013 (has links)
SANTRAUKA
Ingrida ŠINKŪNAITĖ
Mokesčių ir subsidijų įtaka ūkių ekonominiam gyvybingumui
Magistrantūros studijų baigiamasis darbas, 60 puslapių, 46 paveikslai, 16 lentelių, 73 literatūros šaltiniai, 16 priedų, lietuvių kalba.
RAKTINIAI ŽODŽIAI: ekonominis gyvybingumas, žemės ūkis, finansinė analizė, gamybos subsidijos, žemės ūkio mokesčiai, ūkininko ūkis.
Tyrimo objektas – mokesčių ir subsidijų įtaka ūkio ekonominiam gyvybingumui.
Tyrimo tikslas – nustačius veiksnius, sukurti mokesčių ir subsidijų įtakos ūkio ekonominiam gyvybingumui vertinimo metodiką ir įvertinti mokesčių ir subsidijų įtaką ūkio ekonominiam gyvybingumui.
Tyrimo tikslui pasiekti keliami tokie uždaviniai:
• Apibūdinti ūkį ir išanalizuoti S. Šinkūno ūkio finansinę būklę.
• Apibrėžti tyrimui naudojamą – ekonominio gyvybingumo sampratą ir jį lemiančius veiksnius.
• Sudaryti metodiką subsidijų ir mokesčių įtakos ūkio ekonominiam gyvybingumui vertinimui.
• Nustatyti mokesčių ir subsidijų įtaką ūkių ekonominiam gyvybingumui.
Tyrimo metodai – literatūros analizė, lyginamoji, sisteminė, loginė ir analitinė analizė, santykinių rodiklių analizė, grafinis duomenų vaizdavimo būdas bei statistinės analizės metodai.
Tyrimo rezultatai. Pirmoje darbo dalyje išanalizuotas S. Šinkūno ūkis, pateikti pelningumo rodikliai ir nustatyta tyrimo problema. Antroje darbo dalyje atlikta įvairių autorių ekonominio gyvybingumo sampratos interpretacijų analizė, išskirti lemiantys veiksniai. Išanalizavus mokslinę literatūrą sudaryta... [toliau žr. visą tekstą] / SUMMARY
Ingrida ŠINKŪNAITĖ
Influence of Taxes and Subsidies on the Economic Viability of Farms
Final work of University Master Studies consists of 60 pages, 16 tables, 46 figures, 71 references, 16 appendices, in Lithuanian.
KEY WORDS: economic viability, evaluation of the eco¬nomic viability, financial indicators, agriculture.
The object of research – influence of taxes and subsidies on the economic viability of farms.
The purpose of the study is to analyze the theoretical background of tax, to explore the problems of labor income and profit tax, to define how taxes and subsidies affect the economic viability of a farm and recommend the suggestions for the development.
The objectives defined in the theses are to describe and analyze the financial situation of S. Šinkūnas farm, to define the concept of economic viability and its determinants, to develop and use a methodology for the assessment of the influence of subsidies and taxes on the economic viability of a farm, to show trends and make comparison of the farms.
The methods used in the research are analysis of literature, comparative, systematic, logical and analytical analysis, analysis of relative indexes, graphical data display, statistical analysis.
Research results:
In the first part of the study S. Šinkūnas farm is investigated. The profitability indicators are presented and the research problem is defined. The second part of the thesis provides the analysis of various authors’ interpretations of the economic... [to full text]
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