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The Design And Implementation Of Sustainable Plant Diversity Conservation Program For Alpine Meadows And Pastures, Johann Baumgärtner, Josef Hartmann Jan 2001

The Design And Implementation Of Sustainable Plant Diversity Conservation Program For Alpine Meadows And Pastures, Johann Baumgärtner, Josef Hartmann

All Peer-Reviewed Publications

The paper describes the design and implementation of a plant biodeversity conservation program that was developed under funding and time constraints for diverse ecological, social, and institutional environments. The biodiversity program for alpine meadows and pastures located in the Swiss Canton of the Grisons is used as an example. The design of the sustainable program relied on existing legislation, accounted for limited ecological knowledge and expertise, and considered biodiversity as a commonpool resource. The trend to intensified cultivation of restricted areas required fast action, while the sustainability of the program design had to take into account institutional diversity. Fifteen habitats …

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Relationships Of Stemborer Damage And Plant Physical Conditions To Maize Yield In A Semi-Arid Zone Of Eastern Kenya, Josephine Moraa Songa, Zhou Guofa, William Allan Overholt Jan 2001

Relationships Of Stemborer Damage And Plant Physical Conditions To Maize Yield In A Semi-Arid Zone Of Eastern Kenya, Josephine Moraa Songa, Zhou Guofa, William Allan Overholt

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A field survey on maize stemborers, stemborer damage, maize plant physical conditions, and maize yield was conducted in eastern Kenya under natural conditions. Chilo partellus was the dominant stemborer accounting for 89.5 % of all borers. Stemborer damage greatly reduced maize yield, with tunnel lengths greater than 20 cm causing a 40 % reduction of potential yield. A 33 % yield loss was found in plants with more than one stemborer exit hole. Each stemborer (at harvest time) was correlated with a 8-10 % yield loss. Good plant physical characteristics significantly increased grain yield. Principle component analysis showed that stemborer …

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Variation In Lipophorin Titres During Development In Solitarious And Gregarious Schistocerca Gregaria (Forskàl) (Orthoptera: Acrididae), D. O. Ogoyi, E. O. Osir Jan 2001

Variation In Lipophorin Titres During Development In Solitarious And Gregarious Schistocerca Gregaria (Forskàl) (Orthoptera: Acrididae), D. O. Ogoyi, E. O. Osir

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The levels of lipophorin, the principal insect haemolymph lipoprotein, were estimated during the development of solitary and gregarious phases of Schistocerca gregaria using single radial immunodiffusion. In the gregarious phase, lipophorin titres ranged from 6.69 ±0.57 mg/ml in the 3rd nymphal instar to 14.42 ±2.04 mg/ml in mature adults. The titres in the solitary phase were 3.33 ± 0.59 mg/ml in the 3rd nymphal instar and 8.44 + 0.67 mg/ml in mature adults. Peak lipophorin titres occurred in mature adults (14.42 ±2.04 mg/ml) and 5th nymphal instar (8.75 ±0.25 mg/ml) for gregarious and solitary locusts, respectively. Gregarious locusts had significantly …

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Changes In The Distribution Of Lepidopteran Maize Stemborers In Kenya From The 1950s To 1990s, Zhou Guofa, William A. Overholt, Moses B. Mochiah Jan 2001

Changes In The Distribution Of Lepidopteran Maize Stemborers In Kenya From The 1950s To 1990s, Zhou Guofa, William A. Overholt, Moses B. Mochiah

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Three hundred and ninety-two maize fields in the southern arable zone of Kenya were sampled for lepidopteran cereal stemborers from 1996-2000. Chilo partelhis (Swinhoe) was the most abundant stemborer, and was found at all locations with elevations below 1500 m, and at some locations between 1500 and 2300 m. The highest density of C. partelhis was in the semi-arid ecological zone of eastern Kenya. Chilo orichalcociliellus (Strand) was found in the lowland southern coastal area, and a few inland sites on the border of Tanzania in southeastern Kenya. Busseola fusca Fuller was dominant in highland areas. In the Lake Victoria …

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Distribution And Species Composition Of Cereal Stemborers In The Eastern Zone Of Tanzania, E. Nsami, B. Pallangyo, V. Mcoo, C. O. Omwega Jan 2001

Distribution And Species Composition Of Cereal Stemborers In The Eastern Zone Of Tanzania, E. Nsami, B. Pallangyo, V. Mcoo, C. O. Omwega

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A survey was conducted in the four regions of Tanga, Morogoro, Coast and Dar es Salaam in eastern Tanzania to determine the distribution and species composition of cereal stemborers and their natural enemies. A total of 22 fields were sampled in Tanga, 28 in Morogoro, 17 in Coast and one in Dar es Salaam. Chilo parlellns was found to be the predominant species, accounting for 80 % of all stemborers collected. Bnsseolafnsca, Sesamia calamistis and Chilo orichalcociliellus made up 15,4 and less than 1 % of the stemborers collected respectively. Infestation levels varied with the age of the plants, whereby …

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Farmers’ Perceptions Of Importance, Control Methods And Natural Enemies Of Maize Stemborers At The Kenya Coast, M. J. Bonhof, A. Van Huis, F. G. Kiros, N. Dlbogo Jan 2001

Farmers’ Perceptions Of Importance, Control Methods And Natural Enemies Of Maize Stemborers At The Kenya Coast, M. J. Bonhof, A. Van Huis, F. G. Kiros, N. Dlbogo

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A survey among 240 resource-poor farmers at the Kenya coast indicated that insect pests were considered to be the main production constraint. Over 70% of respondents mentioned stemborers to be the most important insect pest. Unlike the eggs and adults, stemborer larvae and pupae were frequently seen by farmers. Alternative gramineous host plants for pests were common near maize fields and were often not destroyed until after the first rains. Nearly all farmers left dry stems and stubble in the field after harvest. Farmers knew of many methods for controlling stemborers, but only 32 and 56% of farmers in Kilifi …

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Properties Of A Factor In Eland Plasma That Inhibits Transformation Of Bloodstream-Form Trypanosoma Brucei Brucei, E. K. Nguu, E. O. Osir Jan 2001

Properties Of A Factor In Eland Plasma That Inhibits Transformation Of Bloodstream-Form Trypanosoma Brucei Brucei, E. K. Nguu, E. O. Osir

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Fresh plasma from the African eland, Taiirotragus oryx, contains a factor that inhibits the transformation of bloodstream-form Trypanosma bnicei bntcei into procyclic (midgut) forms. Heating of the plasma at 42, 50 and 60 °C for 30 min resulted in a 20, 38 and 40% loss of inhibitor activity respectively, whereas only negligible loss occurred below 42 C. Similarly, one and four freeze-thawing cycles resulted in 32 and 60% loss of activity respectively. Inactivation of the inhibitor activity, which occurred rapidly during storage (for example, 80% loss after 7 days at -20 °C) could not be stopped by the addition of …

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Impact Of Solar Radiation Rainfall And Cannibalism On Disappearance Of Maize Stemborers In Kenya, M. J. Bonhof, W. A. Overholt Jan 2001

Impact Of Solar Radiation Rainfall And Cannibalism On Disappearance Of Maize Stemborers In Kenya, M. J. Bonhof, W. A. Overholt

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The effect of solar radiation, rainfall and cannibalism on the disappearance of eggs and larvae of the cereal stemborer Chilo partellus (Swinhoe) were studied. Disappearance and nonviability of egg batches was higher on plants exposed to solar radiation than on shaded plants. Significantly fewer small larvae were recovered from plants exposed to rainfall than from shielded plants. Cannibalism among larvae of the same size was not common except at high larval densities. Contrary to the common belief that disappearance is the result of prédation, these studies show that solar radiation and rainfall might also play an important role in the …

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Distribution And Abundance, In Maize And Sorghum, Of Lepidopteran Stemborers And Associated Indigenous Parasitoids In Zanzibar, E. I. Nlyibigira, Z. S. Abdallah, W. A. Overholt Jan 2001

Distribution And Abundance, In Maize And Sorghum, Of Lepidopteran Stemborers And Associated Indigenous Parasitoids In Zanzibar, E. I. Nlyibigira, Z. S. Abdallah, W. A. Overholt

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Studies to determine the relative abundance and distribution of stemborer species and their associated parasitoids in maize and sorghum were carried out during the 1995-1996 and 19992000 cropping seasons on Unguja and Pemba, the two main islands of Zanzibar. Three stemborer species were found on both islands in maize and sorghum, with the exotic species Chilo partellns (Swinhoe) (Crambidae) being the most abundant and widely distributed species, accounting for 75.3 % of stemborer attack. It was followed by Sesamia calamistis Hampson (Noctuidae) and C/i. oriclialcociliellus Strand (Crambidae). Stemborer abundance was significantly higher in Pemba (1.47 ± 0.20) than Unguja (0.85 …

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Stemborer Research In Zimbabwe: Prospects For The Establishment Of Cotesia Flavipes Cameron, P. Clhnwada, C. O. Omvvega, W. A. Overholt Jan 2001

Stemborer Research In Zimbabwe: Prospects For The Establishment Of Cotesia Flavipes Cameron, P. Clhnwada, C. O. Omvvega, W. A. Overholt

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The stemborers Busseola fnsca (Fuller) and Chilo partellus (Svvinhoe) cause the highest economic damage to maize and sorghum in Zimbabwe. A number of studies on stemborer bioecology and management in Zimbabwe have been conducted, but most are still incomplete. The more important of these are studies on life history, incidence and distribution patterns, host plants, yield losses, chemical control, cultural control, host plant resistance, the use of sex pheromones, and biological control. These are discussed here in detail, and areas where further research is needed are pointed out. As part of an integrated strategy for managing stemborers in Zimbabwe, an …

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Human Health Improvement In Sub-Saharan Africa Through Integrated Management Of Arthropod Transmitted Diseases And Natural Resources., J. Baumgärtner, M. Bieri, G. Buffoni, G. Gilioli, H. Gopalan, J. Greiling, G. Tikubet, I. Van Schayk Jan 2001

Human Health Improvement In Sub-Saharan Africa Through Integrated Management Of Arthropod Transmitted Diseases And Natural Resources., J. Baumgärtner, M. Bieri, G. Buffoni, G. Gilioli, H. Gopalan, J. Greiling, G. Tikubet, I. Van Schayk

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A concept of an ecosystem approach to human health improvement in Sub-Saharan Africa is presented here. Three factors mainly affect the physical condition of the human body: the abiotic environment, vector-transmitted diseases, and natural resources. Our concept relies on ecological principles embedded in a social context and identifies three sets of subsystems for study and management: human disease subsystems, natural resource subsystems, and decision-support subsystems. To control human diseases and to secure food from resource subsystems including livestock or crops, integrated preventive approaches are preferred over exclusively curative and sectorial approaches. Environmental sustainability - the basis for managing matter and …

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Biosystematics Of The Psyttalia Concolor Species Complex (Hymenoptera: Braconidae: Opiinae): The Identity Of Populations Attacking Ceratitis Capitata (Diptera: Tephritidae) In Coffee In Kenya, S. W. Kimani-Njogu, M. K. Trostle, R. A. Wharton, J. B. Woolley, A. Raspi Jan 2001

Biosystematics Of The Psyttalia Concolor Species Complex (Hymenoptera: Braconidae: Opiinae): The Identity Of Populations Attacking Ceratitis Capitata (Diptera: Tephritidae) In Coffee In Kenya, S. W. Kimani-Njogu, M. K. Trostle, R. A. Wharton, J. B. Woolley, A. Raspi

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The identity of a species of Psyttalia, a parasitoid of tephritid fruit flies in Kenya, was investigated. Individuals reared from coffee infested with Ceratitis capitata (Wiedemann) (Medfly) and two other tephritid species in Kenya were compared with individuals of Psyttalia concolor (Szépligeti) from a laboratory culture in Italy used in augmentative biological control of olive fly, Bactrocera oleae (Gmelin). Reciprocal crosses showed full compatibility, with production of viable female offspring. A preliminary morphometric analysis demonstrated that most individuals originating from Italy could be separated from most of those from Kenya based largely on differences in overall size.

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Host Suitability Of Four Cereal Stem Borers (Lepidoptera: Crambidae, Noctuidae) For Different Geographic Populations Of Cotesia Sesamiae (Cameron) (Hymenoptera: Braconidae) In Kenya, Moses B. Mochiah, Adele J. Ngi-Song, William A. Overholt, M. Botchey Jan 2001

Host Suitability Of Four Cereal Stem Borers (Lepidoptera: Crambidae, Noctuidae) For Different Geographic Populations Of Cotesia Sesamiae (Cameron) (Hymenoptera: Braconidae) In Kenya, Moses B. Mochiah, Adele J. Ngi-Song, William A. Overholt, M. Botchey

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This study focused on the suitability of four species of cereal stem borers for the development of five geographic populations of Cotesia sesamiae (Cameron). C. sesamiae, an indigenous larval parasitoid of gramineous stem borers, is widespread in Africa. Four stem borers, Chilo partellus (Swinhoe), Chilo orichalcociliellus Strand (Lepidoptera: Crambidae), Busseola fusca Fuller, and Sesamia calamistis Hampson (Lepidoptera: Noctuidae), were offered to C. sesamiae for oviposition. Parasitoid individuals originated from five locations in Kenya. Biological parameters such as developmental time, percentage parasitism, progeny production, mortality of immature parasitoids, and proportion of female progeny were compared across host species. The two populations …

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Spatial And Temporal Distribution Of Tsetse Fly Trap Catches At Nguruman, Southwest Kenya, A. Odulaja, J. Baumgärtner, S. Mihok, I. M. Abu-Zinid Jan 2001

Spatial And Temporal Distribution Of Tsetse Fly Trap Catches At Nguruman, Southwest Kenya, A. Odulaja, J. Baumgärtner, S. Mihok, I. M. Abu-Zinid

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Spatial and temporal dynamics of rapidly growing populations of tsetse flies at Nguruman, southwest Kenya during 1993-1995, were investigated, following six years of intensive population suppression with traps over a c. 100 km2 area. The two tsetse species present were randomly distributed in the short rainy season, but were aggregated in the dry and long rainy seasons. Maximum temperature was the dominant weather factor associated with the degree of aggregation. Trends in catches at 20 fixed sites along an 18 km north-south axis were weakly correlated between locations, possibly representing population sub-structuring. In particular, trends in population change were poorly …

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Greenhouse Trials Of New Bacillus Thuringiensis Isolates For Control Of Chilo Partellus Larvae In Sorghum, Michael Brownbridge Jan 2001

Greenhouse Trials Of New Bacillus Thuringiensis Isolates For Control Of Chilo Partellus Larvae In Sorghum, Michael Brownbridge

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Eight new Bacillus thuringiensis Berliner (Bt) isolates originally recovered from different source materials and geographic locations in Kenya were tested against Chilo partellus (Swinhoe) on sorghum grown in a greenhouse. All isolates had been demonstrated previously to be toxic to this pest. Bt strains were cultured in a liquid growth medium and preserved as powders for experimental application. Three-week-old sorghum plants (4-6 leaves) were artificially infested with 20 neonate C. partellus and sprayed 24 h later with Bt suspensions. Non-infested sorghum and infested non-treated sorghum served as the comparative checks within each experimental trial. Plant development and dead-heart formation were …

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Distribution And Species Composition Of Stemborers And Their Natural Enemies In Maize And Sorghum In Ethiopia, Emana Getu, W. A. Overholt, E. Kairu Jan 2001

Distribution And Species Composition Of Stemborers And Their Natural Enemies In Maize And Sorghum In Ethiopia, Emana Getu, W. A. Overholt, E. Kairu

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Surveys were conducted to determine the species composition of stemborers and their natural enemies in maize and sorghum in 1999 and 2000 in eastern, northern, southern and western Ethiopia. The six species of stemborers found attacking maize and sorghum were Cltilp partellus (Swinhoe) (Lepidoptera: Crambidae), Busseolafiisca Fuller, Sesamia calamistis Hampson (Lepidoptera: Noctuidae), S. nonagrioides botanephaga Tarns and Bowden (Lepidoptera: Noctuidae), Rhynchaenus niger (Horn) (Coleoptera: Rhynchophoridae) and Pissodes dubious (Stroöm) (Coleoptera: Rhynchophoridae). Twenty species of primary parasitoids of eggs, larvae and pupae of Ch. partellus, B. fusca and S. calamistis were recorded. Other natural enemies, including predators, fungi and nematodes, were …

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Windows Are Key To Keeping Warm In Winter, Donna Falkenborg Jan 2001

Windows Are Key To Keeping Warm In Winter, Donna Falkenborg

All Current Publications

“With the price of fuel skyrocketing, now is the time to think about energy-saving projects around the house, and the best place to start is with your windows,” advises Leona K. Hawks, Utah State University Extension housing specialist.

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Scholarly Publishing And Intellectual Property In The Electronic Environment, Johann Van Reenen Jan 2001

Scholarly Publishing And Intellectual Property In The Electronic Environment, Johann Van Reenen

University Libraries & Learning Sciences Faculty and Staff Publications

Libraries and information service providers cannot stand aloof from the current developments (legal, technological, and organizational) in scholarly publishing. This chapter will discuss these issues and provide ways to influence beneficial change.

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Work And Productivity In The 21st Century, Johann Van Reenen Jan 2001

Work And Productivity In The 21st Century, Johann Van Reenen

University Libraries & Learning Sciences Faculty and Staff Publications

Advances in information technology have created the potential for global markets, virtually integrated work and workplaces, and international workforce development on a scale never before imagined. To capitalize on these developments, countries, organizations and their leaders need to understand the potential, the challenges, the policies and the attitudes that will be required for success in the electronic environment. This chapter provides an overview of the major technology and management trends and the formative role of digital libraries and information science. The characteristics of the 21st century, emerging trends for libraries and information management, knowledge management and technology driven changes, and …

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2000.2 - Music Centre Hwy 30 Arlington, Martin Price Dec 2000

2000.2 - Music Centre Hwy 30 Arlington, Martin Price

School of Architecture Student Projects - Archive

Selected design work from the 2002 fall semester, Studio Martin Price, School of Architecture, The University of Texas at Arlington.

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A “Touching Man” Brings Aacqu Close, Kenneth M. Roemer Dec 2000

A “Touching Man” Brings Aacqu Close, Kenneth M. Roemer

English Faculty Publications - Archive

No abstract provided.

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Sentence Final Particles In Bisu Narrative, Kirk Roger Person Dec 2000

Sentence Final Particles In Bisu Narrative, Kirk Roger Person

Linguistics & TESOL Dissertations - Archive

Particles are a vital component of many Asian languages. Nonetheless, they typically receive little treatment in grammatical studies. This may be due in part to the theoretical orientations of generative grammar which, intentionally or accidentally, can tend to skew data collection and analysis toward theory-predicted sentence alignments (Chu 1998, Chan 1999). In addition, the exact meaning and usage of many particles can be anything but obvious. Even educated native speakers often claim that particles are not “true words” and have no “real” meaning. This dissertation seeks to understand the inner workings of sentence final particles in the Bisu language of …

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Embattled, Mark Tobin Moore Dec 2000

Embattled, Mark Tobin Moore

Graduate Theses, Dissertations, and Problem Reports (ETD)

Paintings in "Embattled" contain images of Second World War American soldiers from the 1998 motion picture, Saving Private Ryan , as well as from 1960s era DC and Marvel brand comics such as Sgt. Fury and His Howling Commandos, GI Combat, and Sgt. Rock. Also included are photocopies or real pieces of wallpaper, flowery fabrics, and snippets of text from popular culture sources. Specific paintings are discussed in relation to personal motivation regarding the use of selected visual metaphors and collage content, as well as the manipulation of traditional and nontraditional support materials such as canvas or pegboard. Creative influences …

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Beyond Brandeis: Exploring The Uses Of Non-Legal Materials In Appellate Briefs, Ellie Margolis Dec 2000

Beyond Brandeis: Exploring The Uses Of Non-Legal Materials In Appellate Briefs, Ellie Margolis

University of San Francisco Law Review

No abstract provided.

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Science Fact Or Science Fiction? The Implications Of Court-Ordered Genetic Testing Under Rule 35, Anthony S. Niedwiecki Dec 2000

Science Fact Or Science Fiction? The Implications Of Court-Ordered Genetic Testing Under Rule 35, Anthony S. Niedwiecki

University of San Francisco Law Review

No abstract provided.

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Fixed Anchors And The Wilderness Act: Is The Adventure Over?, Timothy Dolan Dec 2000

Fixed Anchors And The Wilderness Act: Is The Adventure Over?, Timothy Dolan

University of San Francisco Law Review

No abstract provided.

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Aguilar V. Avis Rent A Car System, Inc.: The California Supreme Court Takes A Divided Freeway To Content-Oriented Regulation Of Workplace Speech, Charles R. Calleros Dec 2000

Aguilar V. Avis Rent A Car System, Inc.: The California Supreme Court Takes A Divided Freeway To Content-Oriented Regulation Of Workplace Speech, Charles R. Calleros

University of San Francisco Law Review

No abstract provided.

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Establishing An Affirmative Governmental Duty To Protect Children's Rights: The European Court Of Human Rights As A Model For The United States Supreme Court, Tania Schriwer Dec 2000

Establishing An Affirmative Governmental Duty To Protect Children's Rights: The European Court Of Human Rights As A Model For The United States Supreme Court, Tania Schriwer

University of San Francisco Law Review

No abstract provided.

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Longwall Weighting Events At Phalen Colliery, Nova Scotia, Canada, Robert J. Macdonald Dec 2000

Longwall Weighting Events At Phalen Colliery, Nova Scotia, Canada, Robert J. Macdonald

Graduate Theses, Dissertations, and Problem Reports (ETD)

Weightings are dynamic phenomenon observed in mines where coal is extracted using the longwall mining method. Weightings are characterized by high convergence rates within the powered supports which maintain roof stability along the longwall face. Rapid convergence is induced by ground pressures that exceed the load capacity of the supports, and forces them to yield. A weighting event need not necessarily impact the mining process negatively, but notable cases exist where weightings have caused extensive damage to roof strata resulting in large roof falls and prolonged periods of lost coal production.;This thesis describes the history of four longwall panels (No's …

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Characterization Of A Novel Methyl Radical Source And Related Thin Film Growth Studies, Jeffrey Stephen Gold Dec 2000

Characterization Of A Novel Methyl Radical Source And Related Thin Film Growth Studies, Jeffrey Stephen Gold

Graduate Theses, Dissertations, and Problem Reports (ETD)

An ultrahigh vacuum compatible methyl (CH3) radical source has been developed. The methyl radicals were generated by dc- and microwave-discharge processes in either of two ways. In the first, argon (Ar) or an Ar/Xe mixture was passed through the discharge to produce inert gas metastables that react with methane to produce the desired species. This was referred to as the indirect mode of operation. In the second or direct mode, an inert gas/methane mixture was passed directly through the discharge. The discharge/reaction products were sampled using a skimmer, and the resulting molecular beam was either characterized using a mass spectrometer …

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