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The article examines the relationship between man and nature in Knut Hamsun's Growth of the soil (1917) and Stina Aronson's This Side of Heaven (1946). Combining an ecocritical and a postcolonial perspective, a set of ideologically charged notions associated with the northern wilderness come in to light. Through depictions of farmers, landscapes, animals, Sámi characters and supernatural elements, the analysis highlights both anthropocentric and colonial tendencies as well as a questioning of the perceived power structures between these actors. Thus, the article can also be regarded a contribution to an ongoing discussion of Hamsun's controversial Nobel Prize-winning novel as an ecological text. The comparative and situated approach helps widen the ecocritical perspective, especially regarding the status of the Sámi in the text., Artikkelen undersøker relasjonen mellom menneske og natur i Knut Hamsuns Markens grøde (1917) og Stina Aronsons Hitom himlen (1946). Et komparativt perspektiv inspirert av postkolonial økokritikk viser at begge tekstene forholder seg aktivt til et sett av ideologisk ladede forestillinger knyttet til den nordlige ødemarken som motivfelt. Ved å sammenligne fremstillinger av bønder, landskap, dyr, samer og overnaturlige krefter, blir det tydelig at forfatternes måte å forholde seg til dette motivfeltet på, er preget av ganske ulike syn på menneske og natur. Artikkelen tar for seg noen pregnante tekststeder der slike ideologiske posisjoner blir særlig tydelige. Dermed kan artikkelen også leses inn i en pågående diskusjon av Hamsuns omstridte nobelprisroman som en økologisk tekst. Det komparative, situerende og ideologikritiske perspektivet bidrar til å nyansere tidligere økokritiske lesninger, særlig knyttet til samenes status i teksten.

Summary The combination of noninvasive compositional analysis by Raman microspectrometry with high-resolution imaging in the scanning electron microscope greatly expands the analytical capabilities of the electron microscope. However, the chemical preparation of scanning electron microscope (SEM) specimens, although adequate for low-resolution imaging of superficial detail, is not the true representation of the chemistry and composition of the sample, as extraction and aggregation artefacts as a result of dehydrating and cross-linking agents are abundant. The original chemical composition and ultrastructure is only preserved using cryo preparation methods. Therefore, a complete cryo transfer flange was designed and built to add cryogenic control of specimens to the configuration of the EMRAM instrument, a combined Raman spectrometer and XL-30 ESEM instrument. The Raman spectra of two model specimen, polystyrene beads and 2.3M sucrose were studied at ambient and cryogenic temperatures as well as during a heating ramp. Comparing the fingerprint regions of polystyrene and sucrose, both measured at ambient and at cryogenic conditions, only small spectral differences were observed for the main peaks of both molecules. A pronounced sharpening of the bands occurred in the 800–400 cm−1 region, a result of the reduction of intermolecular interactions. The enhanced visibility of the lower frequency modes may offer interesting potential for more detailed interpretation of Raman spectra.

Summary The stereological estimation of second-order descriptors of spatial architecture appears to be inherently more time-consuming and labour-intensive than the estimation of first-order quantities (total quantities or ratios). Therefore, far fewer researchers tend to make use of second-order approaches in their stereological research projects. In this paper, we use a tutorial approach to illustrate how a desire for practical simplicity has provided us with a data collection method that can be used to simultaneously estimate both first-order and second-order properties of the microstructure of a defined anatomical feature of an organ. The approach does not rely on new results from theory, but nevertheless allows either isotropic uniform random or vertical uniform random sections to be used to make estimates of a comprehensive list of 10 microstructural parameters using relationships that are well known in the literature. The probe used in all cases is an isotropically distributed Ruler and the data collection protocol is easy to learn and apply. We illustrate the method on brain tissue but emphasize that the approach can also be applied to non-biological material.

Highly connected continuous phases in a porous medium can usefully be described in terms of their connectivity. Appropriate descriptions of connectivity are the connectivity number density or the related quantity Euler number density. Broadly speaking, Euler number density is equal to the number of discrete objects which comprise the phase plus the number of enclosed cavities within those objects less the number of tunnels through the objects, per unit volume. The conneulor is a convenient stereological method for estimating Euler number density. The relevant probes (i.e. disectors) from which the estimate is obtained are randomly positioned and arbitrary orientated pairs of closely spaced parallel planes. We have applied the conneulor method to estimate the Euler number density of the pore space in a cell of sintered silica imaged using a magnetic resonance (MR) microscope. By flooding the cell simultaneously with a mixture of oil and water prior to imaging we were able to obtain a series of 16 contiguous perfectly registered serial MR sections depicting the pore space. The Euler number density of the porous medium estimated from four systematic pairs of consecutive MR images is −5.6 per mm3 with a coefficient of error (CE) of 10–15%. The Euler number density was lower near the walls of the silica cell than the centre, which is consistent with the method of formation of the cell. In contrast to the majority of stereological methods, and in common with the physical disector, the conneulor method requires that deductions are made regarding the changes in the morphology of the structure of interest that occur between the two parallel image planes comprising the sampling probe. We therefore compared estimates of the Euler number density of the pore space obtained by two independent observers. We conclude that careful thought and discussion between observers is required before a definitive set of counts is made. Once mastered the conneulor counting rules are straightforward to apply.

In multiphase systems consisting of ‘particles’ embedded in a matrix the three-dimensional spatial distribution of the particles may represent important structural information. In systems where the matrix is transparent or translucent recent developments in microscopy allow the three-dimensional location of particles to be recorded. Using these data a spatial statistical, or second-order stereological, analysis can be carried out. In second-order stereology functions of interparticle distances are used as summary statistics of the spatial distributions. These statistics show whether the particles are randomly arranged or, more commonly, either clustered together or inhibited from close approach to each other. This paper focuses on the estimation of one of these spatial statistics, the nearest-neighbour distance distribution function or G-function. In practice, estimation of the G-function is plagued by an ‘edge-effect’ bias introduced by the sampling process itself. There exist a number of G-function estimators that tackle this edge effect problem; for single sample ‘bricks’ it can be shown that these estimators become increasingly accurate as the brick size increases, i.e. they are consistent. However, in many practical cases the size of a sampling brick is fixed by experimental constraints and in these circumstances the only way to increase sample size is to take replicated sampling regions. In this paper we review a number of existing G-function estimators and propose a new estimator. These estimators are compared using the criterion of how well they overcome the edge-effect when they are applied to replicated samples of a fixed size of brick. These comparisons were made using Monte-Carlo simulation methods; the results show that three existing estimators are clearly unsuitable for estimating the G-function from replicated sample bricks. Of the other estimators the recommended estimator depends upon the number of replicates taken; however, we conclude that if a total of more than about 800 points are analysed then the bias in the pooled estimate of the G-function can be reduced to tolerable levels.

In this paper, we examine the influence of institutional arrangements on the implementation of local land-use allocations which incorporate tourism, recreational, and amenity (TRA) values, using a case study from British Columbia, Canada. We frame this paper within a conceptualization of postproductivism and pose the question to what extent, and under what conditions, are new local stakeholders, new local agencies, and new local processes effective in allocating land uses which reflect TRA values? Three new land-use proposals which incorporate TRA values are examined to determine where key catalysts for implementation lie. We found that, unlike other research in rural areas of Britain, institutions in British Columbia that have conventionally regulated land use continue to exercise their considerable regulatory and discretionary powers. Though new stakeholders, agencies and processes at the local level have had an impact on planning, they have not been effective in reconfiguring the power structures for actual implementation of land reallocation. This lack of efficacy is attributed in part to the common property character of lands that support TRA values, the associated complexity of property rights regimes, and the large number of stakeholders involved. Furthermore, there is a lack of understanding by regulatory agencies of land resources as community resources, and these agencies continue to grant higher priority to the strategic considerations of higher levels of government rather than to local concerns.

The combination of noninvasive compositional analysis by Raman microspectrometry with high-resolution imaging in the scanning electron microscope greatly expands the analytical capabilities of the electron microscope. However, the chemical preparation of scanning electron microscope (SEM) specimens, although adequate for low-resolution imaging of superficial detail, is not the true representation of the chemistry and composition of the sample, as extraction and aggregation artefacts as a result of dehydrating and cross-linking agents are abundant. The original chemical composition and ultrastructure is only preserved using cryo preparation methods. Therefore, a complete cryo transfer flange was designed and built to add cryogenic control of specimens to the configuration of the EMRAM instrument, a combined Raman spectrometer and XL-30 ESEM instrument. The Raman spectra of two model specimen, polystyrene beads and 2.3M sucrose were studied at ambient and cryogenic temperatures as well as during a heating ramp. Comparing the fingerprint regions of polystyrene and sucrose, both measured at ambient and at cryogenic conditions, only small spectral differences were observed for the main peaks of both molecules. A pronounced sharpening of the bands occurred in the 800-400 cm(-1) region, a result of the reduction of intermolecular interactions. The enhanced visibility of the lower frequency modes may offer interesting potential for more detailed interpretation of Raman spectra.

Geographers or students of human - environment relations have an important role to play in addressing the questions and issues associated with environmental sustainability. It is the authors' thesis that a central weakness in geography's response to environmental problems and to issues of sustainability is the lack of engagement with questions of ethics. An overall ethic of care, respect, and responsibility is proposed. Within this overarching framework, it is suggested that the society - environment relation may be a scale-dependent problem set, with a separate expression of environmental ethics associated with each scale. For example, an ethic appropriate at the planetary scale may differ from that which is pertinent at the local scale. This argument is advanced through examples from religious and secular interpretations of human - environment relations. In a preliminary way, both moral and technical issues associated with different ethical positions are raised and geographers are challenged to consider and debate their implications. It is concluded that without explicit environmental ethical premises, the sustainability debate is indeterminate.

The stereological estimation of second-order descriptors of spatial architecture appears to be inherently more time-consuming and labour-intensive than the estimation of first-order quantities (total quantities or ratios). Therefore, far fewer researchers tend to make use of second-order approaches in their stereological research projects. In this paper, we use a tutorial approach to illustrate how a desire for practical simplicity has provided us with a data collection method that can be used to simultaneously estimate both first-order and second-order properties of the microstructure of a defined anatomical feature of an organ. The approach does not rely on new results from theory, but nevertheless allows either isotropic uniform random or vertical uniform random sections to be used to make estimates of a comprehensive list of 10 microstructural parameters using relationships that are well known in the literature. The probe used in all cases is an isotropically distributed Ruler and the data collection protocol is easy to learn and apply. We illustrate the method on brain tissue but emphasize that the approach can also be applied to non-biological material.

The commercial fungicide methyl 1-[(butylamino) carbonyl]-1H-benzimidazol-2-ylcarbamate (benomyl) is teratogenic in rats. Its mode of action is believed to be related to its ability to inhibit the polymerization of brain tubulin. In this study its effects were studied in cultured neuronal cells during differentiation and neurite outgrowth. Mouse NB2a and human SH-SY5Y neuroblastoma cells were induced to differentiate by addition of dibutyryl cyclic AMP and at the same time were exposed to various concentrations of benomyl. Benomyl significantly inhibited neurite outgrowth in both cell lines at concentrations of 10(-8) M and above with IC50 values of 5.9 x 10(-7) M and 1.0 x 10(-6) M in the NB2a and SH-SY5Y cells respectively. The results show that benomyl inhibits neuronal cell differentiation at concentrations likely to be achieved during the development of fetal abnormalities in rats in vivo.

Retention of basic components of a crude oil by clay-containing reservoir sandstone was studied by flowing crude oil through cores and monitoring the concentration of bases in the effluent. Cores that were H-saturated, H-saturated then aged, and Na-saturated retained 0·82, 0·82, 0·70, and 0·20 meq base/100 g, respectively. Barium exchange capacity values were 0·86, 0·71, and 0·83 meq/100 g. Subsequent floods with water, toluene, and chloroform-acetone removed oil that had increasing concentrations of base and N, indicating that the basic fraction of crude oil was the most difficult fraction to extract from clay mineral surfaces. Retained bases were nitrogenous and the most tenaciously held bases had base/N ratios approaching unity.

Chemical extraction of potassium from soils and micaceous minerals with solutions containing sodium tetraphenylboron : II. Biotite , Chemical extraction of potassium from soils and micaceous minerals with solutions containing sodium ... , مرکز فناوری اطلاعات و اطلاع رسانی کشاورزی