bluuebunny/crossref_metadata_2025 huggingface dataset:
Further structures in the jaw apparatus of limnognathia maerski (micrognathozoa), with notes on the phylogeny of the gnathifera
Authors: Sørensen Martin Vinther
Published: December 2002

The jaws of Limnognathia maerski, Micrognathozoa, were investigated with light‐ and scanning electron microscopy. The study yielded several new structures and sclerites, including the ventral part of main jaw, the pharyngeal lamellae, the manus, the dorsal and ventral fibularium teeth, and a reinterpretation of the fibularium compartmentalization. Furthermore, it was shown that several jaw elements are composed of densely packed rods. Comparison with Rotifera and Gnathostomulida suggested that the micrognathozoan main jaw is homologous with the rotifer incus and the gnathostomulid articularium and that the pseudophalangids (the ventral jaws) and their associated sclerites correspond to the rotifer mallei. These results imply that Micrognathozoa is more closely related to Rotifera than to Gnathostomulida. J. Morphol. 255:131–145, 2003. © 2002 Wiley‐Liss, Inc.
Embryonic and larval staging of summer flounder (paralichthys dentatus)
Authors: Martinez Gabriela M. , Bolker Jessica A.
Published: December 2002

Early development of flatfishes such as the summer flounder Paralichthys dentatus (Pleuronectiformes) has not been extensively documented, largely because of a dearth of material; however, the recent expansion of flatfish aquaculture has made embryos of P. dentatus readily available for developmental studies. We divide development of P. dentatus embryos and larvae into two main periods, pre‐ and posthatching, and assign stages within each of those primary divisions. Stages from fertilization to hatching loosely follow the general teleost staging scheme suggested by Shardo ([1995] J Morphol 225:125–167); stages from hatching through metamorphosis are aligned with the series used for Japanese flounder, P. olivaceus (Minami [1982] Nippon Suisan Gakkaishi 48:1581–1588; Fukuhara [1986] Nippon Suisan Gakkaishi 52:81–91). Although length, width, and age may serve as approximate indicators of developmental progression in summer flounder, these characteristics are too variable to form the sole basis of a staging table. Therefore, we define stages by morphological criteria drawn from the development of the jaw apparatus and digestive system, eye migration, and notochord tip flexion. Examination of these morphological features in hatched larvae allows accurate and consistent assessment of developmental stage despite variation in timing and size. The staging scheme for flounder embryonic and larval development presented here should facilitate both experimental and comparative research on summer flounder and other flatfish species. J. Morphol. 255:162–176, 2003. © 2002 Wiley‐Liss, Inc.
Innovation is not enough: climates for initiative and psychological safety, process innovations, and firm performance
Authors: Baer Markus , Frese Michael
Published: December 2002

This paper contributes to the discussion on contingencies of process innovations by focusing on and introducing organizational‐level constructs of climate for initiative and psychological safety. We argue that process innovations, defined as deliberate and new organizational attempts to change production and service processes, need to be accompanied by climates that complement the adoption and implementation of such innovations. Our study of 47 mid‐sized German companies examines the relation between process innovations, climates for initiative and psychological safety, and firm performance. Results show that climates for initiative and psychological safety were positively related to two measures of firm performance—longitudinal change in return on assets (holding prior return on assets constant) and firm goal achievement—and moderated the relation between process innovations and firm performance. Copyright © 2003 John Wiley & Sons, Ltd.
Influence tactics and work outcomes: a meta‐analysis
Authors: Higgins Chad A. , Judge Timothy A. , Ferris Gerald R.
Published: December 2002

Recent research on influence tactics has focused on the benefits that accrue as a result of using such tactics. The current study utilizes meta‐analytic techniques to estimate the true population correlations between various influence tactics and work‐related outcomes. Results indicate that ingratiation and rationality have positive effects on work outcomes. Additional analyses suggest that these and other influence tactics have significant effects in certain situations and on specific work outcomes. Copyright © 2003 John Wiley & Sons, Ltd.
Late Wisconsin periglacial environments of the southern margin of the Laurentide Ice Sheet reconstructed from pollen analyses
Authors: Heusser Linda , Maenza‐Gmelch Terryanne , Lowell Thomas , Hinnefeld Rebecca
Published: December 2002

Full‐glacial pollen assemblages from four radiocarbon‐dated interstadial deposits in southwestern Ohio and southeastern Indiana imply the presence of herbaceous vegetation (tundra or muskeg with subarctic indicator Selaginella selaginoides) on the southern margin of the Miami lobe of the Laurentide Ice Sheet ca. 20 000 14C yr BP. Scattered Picea (spruce) and possibly Pinus (pine) may have developed regionally ca. 19 000 14C yr BP, and ca. 18 000 14C yr BP, respectively. Spruce stumps in growth position support a local source of pollen. Prior to the ca. 14 000 14C yr BP glacial advance, small amounts of Quercus (oak) and other deciduous pollen suggest development of regional boreal (conifer–hardwood) forests. Copyright © 2002 John Wiley & Sons, Ltd.
High‐resolution study of Icelandic tephras in the Kangerlussuaq Trough, southeast Greenland, during the last deglaciation
Authors: Jennings Anne E. , Grönvold Karl , Hilberman Rachael , Smith Mikie , Hald Morten
Published: December 2002

Tephra abundance data and geochemistry in Late‐glacial and Holocene sediments on the East Greenland shelf are presented. Two well‐known tephras were identified from electron microprobe analysis of tephra shards picked from ash peaks in the cores. These are the Vedde Ash and Saksunarvatn Ash, which probably were deposited on the shelf after transport on drifting ice. The radiocarbon dates (marine reservoir corrected by −550 yr) that constrain the timing of deposition of the tephra layers compare well with the terrestrial and ice‐core ages of the tephras without requiring additional reservoir correction to align them with the known tephra ages. Several prominent tephra layers with a composition of Ash Zone 2 tephra punctuate the deglacial sediments. These tephra peaks coincide with significant light stable isotope events (signifying glacial meltwater) and fine‐grained sediments poor in ice‐rafted detritus. We interpret the Ash Zone 2 tephra peaks as sediment released from the Greenland Ice Sheet during strong melting pulses of the deglaciation. Copyright © 2002 John Wiley & Sons, Ltd.
European quaternary refugia: a factor in large carnivore extinction?
Authors: O'Regan Hannah J. , Turner Alan , Wilkinson David M.
Published: December 2002

The extinction of large carnivores in Europe during the Quaternary is reviewed and the potential role of glacial refugia in these extinctions is investigated using the VORTEX model for population viability analysis. A model was built for a medium sized big cat similar to the extinct Panthera gombaszoegensis utilising life history data from the modern jaguar Panthera onca. This approach highlighted the potential importance of glacial refugia in the extinction process. Even model refugia the size of the Italian peninsula did not guarantee persistence of a population over a 1000 yr time span, illustrating the role of chance in survival in such a refugium. An area the size of the largest Mediterranean island was unable to support a big cat population for a period of 1000 yr. The models also demonstrated the importance of inbreeding as a mechanism for extinction in refugia. It is suggested that repeated genetic bottlenecks during successive glaciations would tend to remove lethal recessive alleles from the population, increasing the probability of survival in refugia in subsequent glaciations. The history of extinction of large carnivores in the European Quaternary is interpreted in the light of these results. Copyright © 2002 John Wiley & Sons, Ltd.
Fission‐track dating of a tephra layer related to Poti‐Malal and Seguro drifts in the Río Grande basin, Mendoza, Argentina
Authors: Espizua Lydia E. , Bigazzi Giulio , Iunes Pedro J. , Hadler Julio C. , Osorio Ana Maria
Published: December 2002

Two old drift units called Poti‐Malal and Seguro have been differentiated in the Río Grande basin based on relative‐age criteria, stratigraphical relationships, morphology and fission‐track dating. A tephra dated at 0.226 ± 0.025 Ma was deposited on the Poti‐Malal drift and underlies the Seguro outwash, which is inferred to equate with marine oxygen isotope stage 6. The stratigraphical position and age suggest that the tephra post‐dates the Poti‐Malal glaciation and that it is older than the Seguro drift. The Poti‐Malal glaciation must be at least as old as Early–Middle Pleistocene, and the Seguro glaciation is assigned to the penultimate glaciation. The tephra unit may have been deposited during marine oxygen isotope stage 7. Copyright © 2002 John Wiley & Sons, Ltd.
Early to middle Holocene silicic tephra horizons from the Katla volcanic system, Iceland: new results from the Faroe Islands
Authors: Wastegård Stefan
Published: December 2002

Comparatively few Icelandic tephra horizons dated to the early part of the Holocene have so far been detected outside Iceland. Here, I present several tephra horizons that have been recorded in a Holocene peat sequence on the Faroe Islands. Geochemical analyses show that at least two dacitic and one rhyolitic tephra layers were erupted from the Katla volcanic system on southern Iceland between ca. 8000 and 5900 cal. yr BP. The upper two layers can be correlated with the SILK tephras described from southern Iceland, whereas the third, dated to ca. 8000 cal. yr BP, has a geochemistry virtually identical to the rhyolitic component of the Vedde Ash. The results suggest that the Late Weichselian and early Holocene eruption history of the Katla volcano was probably more complex than inferred from Iceland. A new, early Holocene rhyolitic tephra dated to ca. 10 500 cal. yr BP probably originates in the Snæfellsnes volcanic centre in western Iceland. These new findings may play an important role in developing a Holocene tephra framework for northwest Europe. Copyright © 2002 John Wiley & Sons, Ltd.
Distribution, sediment magnetism and geochemistry of the Saksunarvatn (10 180 ± 60 cal. yr BP) tephra in marine, lake, and terrestrial sediments, northwest Iceland
Authors: Andrews John T. , Geirsdóttir Aslaug , Hardardóttir Jórunn , Principato Sarah , Grönvold Karl , Kristjansdóttir Gréta B. , Helgadóttir Gudrún , Drexler John , Sveinbjörnsdóttir Arny
Published: December 2002

In 1997, seismic surveys in the troughs off northwest and north Iceland indicated the presence of a major, regional sub‐bottom reflector that can be traced over large areas of the shelf. Cores taken in 1997, and later in 1999 on the IMAGES V cruise, penetrated through the reflector. In core MD99‐2269 in Húnaflóaáll, this reflector is shown to be represented by a basaltic tephra with a geochemical signature and radiocarbon age correlative with the North Atlantic‐wide Saksunarvatn tephra. We trace this tephra throughout northwest Iceland in a series of marine and lake cores, as well as in terrestrial sediments; it forms a layer 1 to 25 cm thick of fine‐ to medium‐grained basaltic volcanic shards. The base of the tephra unit is always sharp but visual inspection and other measurements (carbonate and total organic carbon weight %) indicate a more diffuse upper boundary associated with bioturbation and with sediment reworking. Off northwest Iceland the Saksunarvatn tephra has distinct sediment magnetic properties. This is evident as a dramatic reduction in magnetic susceptibility, an increase in the frequency dependant magnetic susceptibility and ‘hard’ magnetisation in a −0.1T IRM backfield. Geochemical analyses from 11 sites indicate a tholeiitic basalt composition, similar to the geochemistry of a tephra found in the Greenland ice‐core that dates to 10 180 ± 60 cal. yr BP, and which was correlated with the 9000 14C yr BP Saksunarvatn tephra. We present accelerator mass spectrometry 14C dates from the marine sites, which indicate that the ocean reservoir correction is close to ca. 400 yr at 9000 14C yr BP off northwest Iceland. Copyright © 2002 John Wiley & Sons, Ltd.
The Loch Lomond Readvance on the Isle of Mull, Scotland: glacier reconstruction and palaeoclimatic implications
Authors: Ballantyne Colin K.
Published: December 2002

Geomorphological mapping of Mull provides evidence for an icefield 143 km2 in area flanked by six corrie glaciers with a total area of ca. 13 km2. The absence of Lateglacial periglacial features, shorelines and pollen sites from the area occupied by this readvance, together with radiocarbon dating of shell fragments, confirm that it occurred during the Loch Lomond (Younger Dryas) Stade. The thickness of glacigenic deposits within the area of the readvance is attributed to reworking of paraglacial sediments. Up‐valley continuity of recessional moraines indicates that the ice remained active and near to equilibrium during retreat, consistent with slow warming following the coldest part of the stade. Reconstructed equilibrium line altitudes (ELAs) imply vigorous snow‐blowing by westerly winds, and are consistent with a general southwestwards decline in ELAs across the Scottish Highlands. An ELA of 250 m was calculated for the Mull Icefield using an ablation:accumulation balance ratio (ABR) approach. Palaeotemperature and palaeoprecipitation estimates were derived by calculating a theoretical regional ELA from meteorological data and assuming that the combination of temperature and precipitation implied by the theoretical ELA approximates conditions at 250 m on Mull during the Loch Lomond Stade. The result indicates a mean July sea‐level temperature of 5.7 ± 0.5°C and a mean annual precipitation at 250 m of ca. 2700–3800 mm (best estimate 3200 mm), indicating higher precipitation totals than at present owing to more vigorous atmospheric circulation. Copyright © 2002 John Wiley & Sons, Ltd.
Cascaded coherent Stokes Raman scattering in LiNbO3:Mg crystals under excitation of small polarons and phonon polaritons
Authors: Kitaeva G. Kh. , Kuznetsov K. A. , Penin A. N. , Solosin S. V.
Published: December 2002

Dispersion of the real ε′(ν) and the imaginary ε″(ν) parts of the dielectric function was measured by means of cascaded coherent Stokes Raman scattering (CSRS), in the spectral region of phonon polaritons 520–560 cm−1, for single crystals of LiNbO3:Mg, before and after chemical reduction of the samples. Comparison with the results obtained by spontaneous near‐forward Raman scattering showed that the excitation of polaritons under CSRS does not cause any changes in the dielectric function of the unreduced crystal. After the reduction, which leads to the formation of localized charge carriers, small polarons, we found a sufficient increase in the dielectric function imaginary part, measured by CSRS. This reduction‐induced increase reaches its maximum values in the region of Fermi resonance between polariton and biphonon states. The possible origin of this effect, connected with the enhancement of the lattice intermolecular anharmonicity under polaron hopping, is discussed. Copyright © 2002 John Wiley & Sons, Ltd.
Kinetics and mechanism of decomposition of intermediate complex during oxidation of pectate polysaccharide by potassium permanganate in alkaline solutions
Authors: Khairou Khalid S.
Published: December 2002

The kinetics of decomposition of an [Pect·MnVIO42−] intermediate complex have been investigated spectrophotometrically at various temperatures of 15–30°C and a constant ionic strength of 0.1 mol dm−3. The decomposition reaction was found to be first‐order in the intermediate concentration. The results showed that the rate of reaction was base‐catalyzed. The kinetic parameters have been evaluated and found to be ΔS≠ = − 190.06 ± 9.84 J mol−1 K−1, ΔH≠ = 19.75 ± 0.57 kJ mol−1, and ΔG≠ = 76.39 ± 3.50 kJ mol−1, respectively. A reaction mechanism consistent with the results is discussed. © 2002 Wiley Periodicals, Inc. Int J Chem Kinet 35: 67–72, 2003
Study of the reaction methyl 4‐nitrobenzene‐sulfonate + Cl− in mixed hexadecyltrimethyl‐ammonium chloride‐triton X‐100 micellar solutions
Authors: Fernández Gaspar , Rodríguez Amalia , Graciani María del Mar , Muñoz María , Moyá María Luisa
Published: December 2002

The reaction methyl 4‐nitrobenzenesulfonate + Cl− was studied in hexadecyltrimethylammonium chloride (CTAC) in the absence and presence of 0.1 M NaCl, as well as in mixed CTAC/Triton X‐100 (polyoxyethylene(9.5)octylphenyl ether) aqueous micellar solutions with CTAC molar fractions of 0.9, 0.8, 0.7, and 0.6. Conductivity measurements were used to obtain critical micellar concentrations and micellar ionization degrees of the various micellar reaction media. From these data, thermodynamic information on the cationic/nonionic mixed micellar solutions was obtained. Micellar effects on the observed rate constant were explained by pseudophase kinetic models. The estimated second‐order rate constants in the micellar pseudophase of the different micellar reaction media showed that pure CTAC and mixed CTAC/Triton X‐100 micelles, at the high cationic surfactant molar fractions studied, provide reaction sites of similar characteristics at the interfacial region. This was in agreement with previous structural studies carried out on mixed CTAC/Triton X‐100 micellar solutions. © 2002 Wiley Periodicals, Inc. Int J Chem Kinet 35: 45–51, 2003
Theoretical studies on the mechanism and kinetics of the reaction of F atom with NCO radical
Authors: Zhou Zheng‐Yu , Guo Li , Gao Hong‐Wei
Published: December 2002

The reaction of a F atom with an NCO radical was studied at 6‐311+g* level, using DFT methods. All geometries, vibrational frequencies, and energies of different stationary points were calculated by HF, UMP2, and DFT methods, and the results agreed with the experimental values. The vibrational frequencies and vibrational modes of the reactant, intermediates, transition states, and products were calculated and the changes of these frequencies and modes were analyzed. Simultaneously, the vibrational modes of various species were assigned. The relationship and the change among these confirmed the mechanism of the reaction and the process of electron transfer. The major channel for the reaction was found to be the cis‐channel. At the same time the rate constant was estimated. A new method of analyzing reaction mechanism is also presented. © 2002 Wiley Periodicals, Inc. Int J Chem Kinet 35: 52–60, 2003
Kinetics and mechanism of addition of parabanic acid (imidazolidine‐2,4,5‐trione) to oxiranes
Authors: Zarzyka‐Niemiec Iwona , Lubczak Jacek
Published: December 2002

The results of studies on the kinetics of reaction of 1 mol of parabanic acid (imidazolidine‐2,4,5‐trione) with 1 mol of ethylene oxide (oxirane) or propylene oxide (2‐methyloxirane) carried out in the presence of triethylamine catalyst in dimethylsulfoxide solution are presented. A rate equation describing the reaction is presented and the mechanism proposed. The validity of the proposed mechanism is proved by instrumental analytical methods. The effect of temperature is also presented and the thermodynamic parameters of the reaction evaluated. © 2002 Wiley Periodicals, Inc. Int J Chem Kinet 35: 73–80, 2003
Nonequilibrium solvent polarization in kinetics of SN2 reactions
Authors: Jaworski J. S.
Published: December 2002

The solvent effect on the experimental activation barriers for the reactions of methyl iodide with chloride and thiocyanate ions was analyzed according to the Marcus and Shaik theories, considering SN2 mechanism in terms of a single electron shift. The linear increase in the solvent reorganization energy of the Marcus theory (after removing contributions from the specific solvation) with the solvent Pekar factor, describing the effect of the nonequilibrium solvent polarization, was observed for six aprotic solvents. The direct support of the title effect based on the Shaik theory was less evident; however, in general, the calculated activation barriers in 10 solvents change parallel with the experimental ones. © 2002 Wiley Periodicals, Inc. Int J Chem Kinet 35: 61–66, 2003
Relative rate constants for the reactions of hydroxyl radicals and chlorine atoms with a series of aliphatic alcohols
Authors: Wu Hai , Mu Yujing , Zhang Xiaoshan , Jiang Guibin
Published: December 2002

Rate constants for the gas‐phase reactions of hydroxyl radicals and chlorine atoms with a series of alcohols have been determined by using the relative method. The experiments were performed at 295 ± 2 K and at 1 atmospheric pressure. The obtained values of the rate constants in units of 10−12 cm3 molecule−1 s−1 are as follows:

Alcohol
Rate Constants for OH with
Rate Constants for Cl with

Propane
Cyclohexane
Propane
Cyclohexane

Ethyl alcohol
3.40 ± 0.25
–
103 ± 4
96 ± 7

n‐Propyl alcohol
5.47 ± 0.44
–
153 ± 13
147 ± 11

Isopropyl alcohol
5.31 ± 0.39
–
73.5 ± 3.7
82.7 ± 7.4

n‐Butyl alcohol
8.66 ± 0.66
–
211 ± 11
223 ± 10

Isobutyl alcohol
9.08 ± 0.35
9.59 ± 0.45
182 ± 4
196 ± 11

tert‐Butyl alcohol
1.11 ± 0.07
–
31.5 ± 2.4
34.1 ± 2.5

n‐Pentyl alcohol
12.2 ± 1.0
12.4 ± 0.5
257 ± 25
258 ± 12

Isopentyl alcohol
13.8 ± 0.5
13.2 ± 1.1
237 ± 7
235 ± 9

The above relative rate constants are based on the values (in units of 10−12 cm3 molecule−1 s−1) of k(OH + propane) = 1.08, k(OH + cyclohexane) = 7.22, k(Cl + propane) = 131 and k(Cl + cyclohexane) = 307. The results are compared with previous determinations. © 2002 Wiley Periodicals, Inc. Int J Chem Kinet 35: 81–87, 2003
Revegetation of mining spoils by seeding of woody species on Ghiona Mountain, central Greece
Authors: Brofas G. , Karetsos G.
Published: December 2002

The reforestation potential of calcareous bauxite mining spoils by seeding was examined on experimental plot established at Strofi Koukouvista 5, Mount Ghiona in Central Greece. The experiment consists of three species (Pinus nigra, Robinia pseudoacacia, and Spartium junceum) with four sowing treatments and two sowing seasons (autumn and spring). The treatments were: broadcasting (B); broadcasting and soil cultivation (BC); broadcasting with straw mulching and straw binding with asphalt emulsion (BM); broadcasting with soil cultivation, straw mulching and straw binding with asphalt emulsion (BCM). In all cases sowing in spring was better than in autumn. Only Spartium junceum has germinated and survived in autumn, but less than in spring. The most effective treatments for Robinia pseudoacacia and Pinus nigra are BM and BCM while for Spartium junceum even simple broadcasting shows good results although the best are achieved with treatments BC, BM and BCM. The findings show that reforestation by sowing could be effective for some species, but further experimentation with other species and methods is recommended. Copyright © 2002 John Wiley & Sons, Ltd.
Soil carbon sequestration in China through agricultural intensification, and restoration of degraded and desertified ecosystems
Authors: Lal R.
Published: December 2002

The industrial emission of carbon (C) in China in 2000 was about 1 Pg yr−1, which may surpass that of the United States (1ċ84 Pg C) by 2020. China's large land area, similar in size to that of the United States, comprises 124 Mha of cropland, 400 Mha of grazing land and 134 Mha of forestland. Terrestrial C pool of China comprises about 35–60 Pg in the forest and 120–186 Pg in soils. Soil degradation is a major issue affecting 145 Mha by different degradative processes, of which 126 Mha are prone to accelerated soil erosion. Total annual loss by erosion is estimated at 5ċ5 Pg of soil and 15ċ9 Tg of soil organic carbon (SOC). Erosion‐induced emission of C into the atmosphere may be 32–64 Tg yr−1. The SOC pool progressively declined from the 1930s to 1980s in soils of northern China and slightly increased in those of southern China because of change in land use. Management practices that lead to depletion of the SOC stock are cultivation of upland soils, negative nutrient balance in cropland, residue removal, and soil degradation by accelerated soil erosion and salinization and the like. Agricultural practices that enhance the SOC stock include conversion of upland to rice paddies, integrated nutrient management based on liberal use of biosolids and compost, crop rotations that return large quantities of biomass, and conservation‐effective systems. Adoption of recommended management practices can increase SOC concentration in puddled soil, red soil, loess soils, and salt‐affected soils. In addition, soil restoration has a potential to sequester SOC. Total potential of soil C sequestration in China is 105–198 Tg C yr−1 of SOC and 7–138 Tg C yr−1 for soil inorganic carbon (SIC). The accumulative potential of soil C sequestration of 11 Pg at an average rate of 224 Tg yr−1 may be realized by 2050. Soil C sequestration potential can offset about 20 per cent of the annual industrial emissions in China. Copyright © 2002 John Wiley & Sons, Ltd.
Land degradation is contextual
Authors: Warren A.
Published: December 2002

Land degradation cannot be judged independently of its spatial, temporal, economic, environmental and cultural context. Evaluations are therefore almost infinitely variable and very dynamic. These observations are examined in two contexts, first in two case studies. One, from the southern Levant, makes use of a long and well‐documented history of environmental assessment that varied greatly between communities. The other, from contemporary Niger, shows finer scale differences among villagers. Second, the dynamic and multiple assessment of futures (sustainability) is illustrated with data from the same case study in Niger. In this wider context, multiplicity and dynamicity are largely a consequence of the choice of model of the environmental or social future. The usually positive difference between large‐scale and finer scale assessments of degradation is dubbed the [social delivery ratio]. Simplified systems of evaluation may be necessary for allocation, but they need to be treated with great caution if the argument here is accepted. Copyright © 2002 John Wiley & Sons, Ltd.
Farmland degradation in the mountains of Nepal: a study of watersheds ‘with’ and ‘without’ external intervention
Authors: Thapa G. B. , Paudel G. S.
Published: December 2002

Amidst growing concerns about farmlands conservation, this paper examines the status of farmlands in two mountain watersheds ‘with’ and ‘without’ external intervention, located in the western hills of Nepal. Information was obtained from a household survey and group discussions conducted during April to September 1999. The severity of soil erosion from farmers' perspectives, density of landslides, soil nutrient balance and change in crop yield have been adopted as indicators of the status of the land. Results of the analysis indicate that land resources in both watersheds are undergoing degradation, though the causes and extent of degradation vary from one type of land to another. Upland crop terraces, locally called bari, are undergoing degradation most seriously under the combined influence of severe soil erosion, landslide and the depletion of soil nutrients. In particular, soil erosion has severely affected nearly half of the upland crop terraces in both watersheds due to a number of natural and anthropogenic factors ranging from weak geological structure to arable agriculture. Landslide and nutrient depletion have affected all types of farmlands except homesteads in both watersheds. Overall, the extent and intensity of land degradation is relatively high in the non‐project area, as farmers were not provided with necessary technical and financial support. A broad strategy has been outlined for effective conservation of farmlands. Copyright © 2002 John Wiley & Sons, Ltd.
Land‐use change in two Nepalese watersheds: GIS and geomorphometric analysis
Authors: Awasthi K. D. , Sitaula B. K. , Singh B. R. , Bajacharaya R. M.
Published: December 2002

Accurate measurement of land‐use/land‐cover and geomorphometric parameters is important for evaluating watershed conditions, yet these are surprisingly difficult quantities to measure accurately over large areas. Watershed analysis based on the geographic information system (GIS) was carried out in two watersheds in the western development region of Nepal. Land‐use maps were prepared after interpretation of 1978 and 1996 aerial photographs. Digital data for deriving geomorphometric parameters were prepared from topographical maps of scale 1: 25 000. The dynamics of land‐use and land‐cover change within the Mardi and Fewa watersheds were investigated by performing spatial analysis of digital land‐use maps in ArcView 3.1 desktop environment. There was a net increase in forest cover of 2ċ4 per cent and 1ċ1 per cent in the Mardi and Fewa watersheds respectively, with a corresponding decrease in shrub and rainfed agriculture. Land use was found to be highly dynamic with significant internal trading among the land‐use classes. A significant area under agriculture in 1978 was found abandoned in 1996 in both watersheds most likely due to increased out migration of the labour force. Geomorphometric parameters such as hypsometric curves, hypsometric integrals (HI), drainage density and length of overland flow were analysed to explain the watershed conditions. The results of geomorphometric analysis revealed that the watersheds have been subjected in the past to high erosion and are still susceptible to lateral surface erosion hence soil degradation. Some suggestion for management can be derived from this study. Copyright © 2002 John Wiley & Sons, Ltd.
Aggregates stability and water erosion in Andosols of the Canary Islands
Authors: Rodríguez Rodríguez A. , Guerra J. A. , Gorrín S. P. , Arbelo C. D. , Mora J. L.
Published: December 2002

The aim of this paper is to assess the mechanisms of water erosion in andic soils using two tests, which in a certain way simulate the two principal mechanisms of aggregate destruction in the process of water erosion—water dispersion and raindrops impact—and compare them with the aggregation observed in material dettached by inter‐rill erosion (sediments) in experimental plots with natural rain. In accordance with the obtained results, the erosive process in these soils seems to come about through a picking off of surface material of larger aggregates, due to the impact of raindrops. The intensity of pull off and fragment size from larger aggregates depends on the kinetic energy of the drops (rain intensity), but the size generally ranges between 0ċ2 and 0ċ5 mm. Therefore inter‐rill erosion initially proceeds by a washing down of smaller aggregates (<0ċ5 mm) (of less bulk density than larger aggregates 0ċ4 Mg m−3 against 0ċ9 Mg m−3), enriching the soil in larger sized aggregates which, on being fragmented by picking off of raindrops, supply new material for washing down by inter‐rill erosion. Copyright © 2002 John Wiley & Sons, Ltd.
Uniform corrosion of titanium in alkaline hydrogen peroxide conditions: influence of transition metals and inhibitors calcium and silicate
Authors: Rämö J. , Saarinen K. , Sillanpää M.
Published: December 2002

Uniform corrosion of titanium was studied in alkaline hydrogen peroxide environments simulating pulp bleaching conditions. Corrosion rates of unalloyed Grade 2 and alloyed Grade 5 were determined as a function of hydrogen peroxide anion (HOO−) concentration. Influences of calcium and silicate inhibitors and iron and manganese were investigated. Without inhibition titanium corroded at HOO− content of 200 mg/l: Grade 2 0.4 mm/y and Grade 5 1.4 mm/y. Addition of calcium (Ca2+) and silicate (SiO32−) diminished the corrosion of Grade 2 to critical anion level 400 mg/l, but could not protect Grade 5 even at the HOO− concentration of 300 mg/l. Presence of iron and manganese raised the critical levels of the both grades. High HOO− anion level was observed as a notable potential difference between titanium and platinum.
Adaptive crack propagation analysis with the element‐free Galerkin method
Authors: Lee Gye‐Hee , Chung Heung‐Jin , Choi Chang‐Koon
Published: December 2002

In this paper, an adaptive analysis of crack propagation based on the error estimation by the element‐free Galerkin (EFG) method is presented. The adaptivity analysis in quasi‐static crack propagation is achieved by adding and/or removing the nodes along the background integration cells, those are refined or recovered according to the estimated errors. These errors are obtained basically by calculating the difference between the values of the projected stresses and original EFG stresses. To evaluate the performance of the proposed adaptive procedure, the crack propagation behaviour is investigated for several examples. The results of these examples show the efficiency and accuracy of the proposed scheme in crack propagation analysis. Copyright © 2002 John Wiley & Sons, Ltd.
Thermoelastic stress field in a piecewise homogeneous domain under non‐uniform temperature using a coupled boundary and finite element method
Authors: Guven I. , Madenci E.
Published: December 2002

This study concerns the development of a coupled finite element–boundary element analysis method for the solution of thermoelastic stresses in a domain composed of dissimilar materials with geometric discontinuities. The continuity of displacement and traction components is enforced directly along the interfaces between different material regions of the domain. The presence of material and geometric discontinuities are included in the formulation explicitly. The unknown interface traction components are expressed in terms of unknown interface displacement components by using the boundary element method for each material region of the domain. Enforcing the continuity conditions leads to a final system of equations containing unknown interface displacement components only. With the solution of interface displacement components, each region has a complete set of boundary conditions, thus leading to the solution of the remaining unknown boundary quantities. The concepts developed for the BEM formulation of a domain with dissimilar regions is employed in the finite element–boundary element coupling procedure. Along the common boundaries of FEM–BEM regions, stresses from specific BEM regions are first expressed in terms of interface displacements, then integrated and lumped at the nodal points of the common FEM–BEM boundary so that they are treated as boundary conditions in the analysis of FEM regions along the common FEM–BEM boundary. Copyright © 2002 John Wiley & Sons, Ltd.
Transient heat conduction analysis in a piecewise homogeneous domain by a coupled boundary and finite element method
Authors: Guven I. , Madenci E.
Published: December 2002

A coupled finite element–boundary element analysis method for the solution of transient two‐dimensional heat conduction equations involving dissimilar materials and geometric discontinuities is developed. Along the interfaces between different material regions of the domain, temperature continuity and energy balance are enforced directly. Also, a special algorithm is implemented in the boundary element method (BEM) to treat the existence of corners of arbitrary angles along the boundary of the domain.

Unknown interface fluxes are expressed in terms of unknown interface temperatures by using the boundary element method for each material region of the domain. Energy balance and temperature continuity are used for the solution of unknown interface temperatures leading to a complete set of boundary conditions in each region, thus allowing the solution of the remaining unknown boundary quantities.

The concepts developed for the BEM formulation of a domain with dissimilar regions is employed in the finite element–boundary element coupling procedure. Along the common boundaries of FEM–BEM regions, fluxes from specific BEM regions are expressed in terms of common boundary (interface) temperatures, then integrated and lumped at the nodal points of the common FEM–BEM boundary so that they are treated as boundary conditions in the analysis of finite element method (FEM) regions along the common FEM–BEM boundary. Copyright © 2002 John Wiley & Sons, Ltd.
Imposition of boundary conditions by modifying the weighting coefficient matrices in the differential quadrature method
Authors: Fung T. C.
Published: December 2002

One of the important issues in the implementation of the differential quadrature method is the imposition of the given boundary conditions. There may be multiple boundary conditions involving higher‐order derivatives at the boundary points. The boundary conditions can be imposed by modifying the weighting coefficient matrices directly. However, the existing method is not robust and is known to have many limitations. In this paper, a systematic procedure is proposed to construct the modified weighting coefficient matrices to overcome these limitations. The given boundary conditions are imposed exactly. Furthermore, it is found that the numerical results depend only on those sampling grid points where the differential quadrature analogous equations of the governing differential equations are established. The other sampling grid points with no associated boundary conditions are not essential. Copyright © 2002 John Wiley & Sons, Ltd.
Minimum weight design of non‐linear elastic structures with multimodal buckling constraints
Authors: Trentadue Francesco
Published: December 2002

It well known that multimodal instability is an event particularly relevant in structural optimization. Here, in the context of non‐linear stability theory, an exact method is developed for minimum weight design of elastic structures with multimodal buckling constraints. Given an initial design, the method generates a sequence of improved designs by determining a sequence of critical equilibrium points related to decreasing values of the structural weight. Multimodal buckling constraints are imposed without repeatedly solving an eigenvalue problem, and the difficulties related to the non‐differentiability in the common sense of state variables in multimodal critical states, are overcome by means of the Lagrange multiplier method. Further constraints impose that only the first critical equilibrium states (local maxima or bifurcation points) on the initial equilibrium path of the actual designs are taken into account. Copyright © 2002 John Wiley & Sons, Ltd.
Finite element computation of sloshing modes in containers with elastic baffle plates
Authors: Bermúdez Alfredo , Rodríguez Rodolfo , Santamarina Duarte
Published: December 2002

A finite element method to approximate the vibration modes of a plate in contact with an incompressible fluid is analysed in this paper.

The effect of the fluid is taken into account by means of an added mass formulation, discretized by standard piecewise linear tetrahedral finite elements. Gravity waves on the free surface of the liquid are considered in the model. The plate is modelled by Reissner–Mindlin equations discretized by MITC3 locking‐free elements.

Implementation issues are discussed and numerical experiments are presented. In particular, the method is compared with analytical approximations and with an experimental study which has been recently reported. Copyright © 2002 John Wiley & Sons, Ltd.
Two trigonometric quadrature formulae for evaluating hypersingular integrals
Authors: Kim Philsu , Choi U. Jin
Published: December 2002

Two trigonometric quadrature formulae, one of non‐interpolatory type and one of interpolatory type for computing the hypersingular integral ${\int\hskip-0.33cm=}_{-1}^{1} w(\tau)g(\tau)/(\tau-t)^{2} \,{\rm d}\tau$ are developed on the basis of trigonometric quadrature formulae for Cauchy principal value integrals. The formulae use the cosine change of variables and trigonometric polynomial interpolation at the practical abscissae. Fast three‐term recurrence relations for evaluating the quadrature weights are derived. Numerical tests are carried out using the current formula. As applications, two simple crack problems are considered. One is a semi‐infinite plane containing an internal crack perpendicular to its boundary and the other is a centre cracked panel subjected to both normal and shear tractions. It is found that the present method generally gives superior results. Copyright © 2002 John Wiley & Sons, Ltd.
Lessons learned from a small native American community
Authors: Espeland Wendy Nelson
Published: December 2002

The decision not to build Orme Dam was a great political victory for residents of the Fort McDowell Indian Reservation in central Arizona. This article examines the conditions that gave rise to what most considered an unlikely outcome, and the lessons it suggests for understanding the politics of large water projects. These lessons include the importance of understanding that rationality takes multiple forms; that how value is expressed can be as significant as what, and how much, something is valued; that identity politics which elaborates and celebrates cultural differences can be an effective means for challenging even powerful bureaucracies; and that law can be an important mediating structure in the politics of bureaucratic decision‐making. Copyright © 2002 John Wiley & Sons, Ltd.
Popular mobilization and disaster management in Cuba
Authors: Sims Holly , Vogelmann Kevin
Published: December 2002

Cuba has effectively implemented a system of popular mobilization and education to prepare people for such natural disasters as hurricanes. Compliance with evacuation orders is impressive. Top priority is attached to saving lives. The country's acclaimed programme accounts for the limited toll of Hurricane Michelle in November 2001, which was the most powerful storm since 1944. Five Cubans died in the storm, which wreaked havoc in Jamaica, Honduras, and Nicaragua. This article reviews recent Cuban experience in disaster preparedness, which was achieved despite material scarcity. Since the prestigious Intergovernmental Panel on Climate Change warns of increased susceptibility to disasters in future, Cuba's record deserves wide attention. Copyright © 2002 John Wiley & Sons, Ltd.
Three Gorges Project: the largest water conservancy project in the world
Authors: Jiazhu Wang
Published: December 2002

The Three Gorges Project (TGP) is the largest water conservancy project ever built in China and in the world. Construction of TGP commenced in 1993 and more than half is complete. It is predicted that the project will be put into initial use in 2003, and finished in 2009. This article discusses the project's advantages and some of the challenges faced, including technical, environmental and resettlement issues. Copyright © 2002 John Wiley & Sons, Ltd.
Nonprofit organizations as contracted local social service providers in eastern Europe and the Commonwealth of Independent States
Authors: Struyk Raymond J.
Published: December 2002

Today nonprofit organizations (NPOs) are an important provider of social services in some countries in the eastern Europe‐CIS region. Based on field reports from seven countries in the region, we find that the pattern is highly variable, however; and only in central Europe and Croatia are local governments contracting with NPOs to deliver services. More commonly, local governments give grants to NPOs for this purpose. But in some countries local governments provide essentially no support to NPOs for social service delivery. This article outlines the case for NPOs being contracted as service providers, and inventories the current situation in the region with respect to local governments. It concludes with a discussion of the possible reasons for the low incidence of contracting by local governments with NPOs as service providers. Copyright © 2002 John Wiley & Sons, Ltd.
What could be achieved with greater public hospital autonomy? Comparison of public and PNFP hospitals in Uganda
Authors: Ssengooba Freddie , Atuyambe Lynn , McPake Barbara , Hanson Kara , Okuonzi Sam
Published: December 2002

The policy of hospital autonomy has been discussed for some time in Uganda. There is little evidence from Uganda or elsewhere that increased autonomy will improve hospital performance. This article compares the performance of three private not‐for‐profit (PNFP) and public hospital pairs to address this question. PNFP and public hospitals have similar management structures but PNFP hospitals had better trained managers and a church affiliated chair in the hospital management committee. Both types have problems with personnel management but these appear more pronounced in public hospitals. Drug supply management appears better in PNFP hospitals. Overall, workloads are similar, but analysis of patterns of utilisation and prices across services suggest that patient choice of facilities is influenced by relative price levels, and that willingness to pay is higher for PNFP services. PNFP hospitals are more successful at generating revenue. There are no clear differences in efficiency between PNFP and public hospitals but there is some evidence of higher quality levels in PNFP hospitals. PNFP hospitals' performance is plausibly related to three areas of managerial autonomy. First, better management of drug supply is facilitated by their freedom to purchase drugs from the open market. Second, greater success with personnel management is plausibly related to their greater autonomy over staffing. Third, higher levels of cost recovery are enabled by their freedom to set fees. However, differences in accountability and competence of hospital management, and population willingness to pay for services may also help to explain differences. Further, the use of PNFP financing strategy by public hospitals has implications for universal access to hospital services. Although there appear to be potential advantages from greater public hospital autonomy, the Ugandan government should ensure it has developed strategies to enhance public hospital management and to protect access to public hospitals before advancing further with hospital autonomy policy. Copyright © 2002 John Wiley & Sons, Ltd.
Ethnography of a policy process: a case study of land redistribution in Bangladesh
Authors: Devine Joseph
Published: December 2002

Throughout the developing world, Non Governmental Organisations (NGOs) are involved in various aspects of an increasing number of policy interventions. The donor community has lent considerable support to this strategy. One of the key assumptions behind the strategy is that the greater involvement of NGOs in policy processes will result in more resources being distributed to the poor, and will also facilitate the establishment of a policy process which is more inclusive and egalitarian. Here the involvement of NGOs in an important land redistribution policy initiative is used to examine both these assumptions. While there is strong evidence that more land was redistributed to the poor as a result of NGO involvement, the actual mechanism or process for deciding the distribution of land was not found to be all inclusive or completely egalitarian. This ambivalence serves as a timely critique to the naive optimism and simplified assumptions underpinning development thinking and practice. Copyright © 2002 John Wiley & Sons, Ltd.