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Showing papers by "University of Hawaii at Manoa published in 1996"


Journal ArticleDOI
TL;DR: In this paper, the authors present a model of the growth strategy of the firm in planned economies in transition such as Eastern Europe, the former Soviet republics, and China, focusing on the stylized state-owned enterprises.
Abstract: Highlighting an important facet of diversity among organizations operating in different institutional environments, this article presents a model of the growth strategy of the firm in planned economies in transition such as Eastern Europe, the former Soviet republics, and China. Focusing on the stylized state-owned enterprises, we explore the interaction between institutions and organizations in these countries. Given the institutional constraints, neither generic expansion nor acquisitions, two traditional strategies for growth found in the West, are viable for firms in these countries. Instead, firms settle on a network-based strategy of growth, building on personal trust and informal agreements among managers. The institutional environment that leads to this unique strategy of growth is examined, and boundary conditions, limitations, and implications of this model are discussed.

1,758 citations


Journal ArticleDOI
TL;DR: It is proposed that the genotype‐phenotype map can evolve by two main routes: epistatic mutations, or the creation of new genes, a common result for organismic design is modularity.
Abstract: The problem of complex adaptations is studied in two largely disconnected research traditions: evolutionary biology and evolutionary computer science. This paper summarizes the results from both areas and compares their implications. In evolutionary computer science it was found that the Darwinian process of mutation, recombination and selection is not universally effective in improving complex systems like computer programs or chip designs. For adaptation to occur, these systems must possess "evolvability," i.e., the ability of random variations to sometimes produce improvement. It was found that evolvability critically depends on the way genetic variation maps onto phenotypic variation, an issue known as the representation problem. The genotype-phenotype map determines the variability of characters, which is the propensity to vary. Variability needs to be distinguished from variations, which are the actually realized differences between individuals. The genotype-phenotype map is the common theme underlying such varied biological phenomena as genetic canalization, developmental constraints, biological versatility, developmental dissociability, and morphological integration. For evolutionary biology the representation problem has important implications: how is it that extant species acquired a genotype-phenotype map which allows improvement by mutation and selection? Is the genotype-phenotype map able to change in evolution? What are the selective forces, if any, that shape the genotype-phenotype map? We propose that the genotype-phenotype map can evolve by two main routes: epistatic mutations, or the creation of new genes. A common result for organismic design is modularity. By modularity we mean a genotype-phenotype map in which there are few pleiotropic effects among characters serving different functions, with pleiotropic effects falling mainly among characters that are part of a single functional complex. Such a design is expected to improve evolvability by limiting the interference between the adaptation of different functions. Several population genetic models are reviewed that are intended to explain the evolutionary origin of a modular design. While our current knowledge is insufficient to assess the plausibility of these models, they form the beginning of a framework for understanding the evolution of the genotype-phenotype map.

1,497 citations


Journal ArticleDOI
10 Oct 1996-Nature
TL;DR: Observations provide unequivocal support for the hypothesis that phytoplankton growth in this oceanic region is limited by iron bioavailability.
Abstract: The seeding of an expanse of surface waters in the equatorial Pacific Ocean with low concentrations of dissolved iron triggered a massive phytoplankton bloom which consumed large quantities of carbon dioxide and nitrate that these microscopic plants cannot fully utilize under natural conditions. These and other observations provide unequivocal support for the hypothesis that phytoplankton growth in this oceanic region is limited by iron bioavailability.

1,318 citations


Journal ArticleDOI
TL;DR: In this article, the authors assess the relative role of national and corporate cultural fit in predicting effective integration between merger partners by examining both international and domestic mergers, and their findings confirm that cultural fit is separate constructs with variable attitudinal and behavioral correlates.
Abstract: While cultural fit has been acknowledged to be a potentially important factor in mergers and acquisitions, the concept has been ill-defined, with no distinction drawn between the national and corporate levels of culture. By examining both international and domestic mergers, the present study assesses the relative role of national and corporate cultural fit in predicting effective integration between merger partners. The innovative, nonparametric co-plot method is introduced, and its main advantage-the simultaneous consideration of both variables and observations-is utilized to explore cultural fit in the two groups of mergers. The findings confirm that national and corporate culture are separate constructs with variable attitudinal and behavioral correlates.

604 citations


Journal ArticleDOI
TL;DR: In this article, the authors develop an explanation for IPO underpricing in which the issuer's demand for ownership dispersion creates an incentive to underprice, and empirical results are consistent with initial under-pricing reflecting the level of ownership disersion.

582 citations


Journal ArticleDOI
25 Sep 1996-JAMA
TL;DR: Prevalence of Alzheimer disease in older Japanese-American men in Hawaii appears to be higher than in Japan but similar to European-ancestry populations.
Abstract: Objective. —To determine prevalence of dementia and its subtypes in Japanese-American men and compare these findings with rates reported for populations in Japan and elsewhere. Design and Setting. —The Honolulu Heart Program is a prospective populationbased study of cardiovascular disease established in 1965. Prevalence estimates were computed from cases identified at the 1991 to 1993 examination. Cognitive performance was assessed using standardized methods, instruments, and diagnostic criteria. Participants. —Subjects were 3734 Japanese-American men (80% of surviving cohort) aged 71 through 93 years, living in the community or in institutions. Main Outcome Measures. —Age-specific, age-standardized, and cohort prevalence estimates were computed for dementia (all cause) defined by 2 sets of diagnostic criteria and 4 levels of severity. Prevalence levels for Alzheimer disease and vascular dementia were also estimated. Results. —Dementia prevalence byDiagnostic and Statistical Manual of Mental Disorders, Third Edition, Revisedranged from 2.1% in men aged 71 through 74 years to 33.4% in men aged 85 through 93 years. Age-standardized prevalence was 7.6%. Prevalence estimates for the cohort were 9.3% for dementia (all cause), 5.4% for Alzheimer disease (primary or contributing), and 4.2% for vascular dementia (primary or contributing). More than 1 possible cause was found in 26% of cases. The Alzheimer disease/vascular dementia ratio was 1.5 for cases attributed primarily to Alzheimer disease or vascular dementia. Conclusions. —Prevalence of Alzheimer disease in older Japanese-American men in Hawaii appears to be higher than in Japan but similar to European-ancestry populations. Prevalence of vascular dementia appears to be only slightly lower than in Japan, but higher than in European-ancestry populations. Further cross-national research with emphasis on standardized diagnostic methods is needed.

444 citations


Journal ArticleDOI
TL;DR: In this paper, the effects of temperature, pressure, reactant concentration, weight hourly space velocity, and the type of catalyst on the gasification of glucose are reported, and complete conversion of glucose (22% by weight in water) to a hydrogen-rich synthesis gas was realized at a weight hourly velocity (WHSV) of 22.2 h-1 in supercritical water at 600 °C, 34.5 MPa.
Abstract: Spruce wood charcoal, macadamia shell charcoal, coal activated carbon, and coconut shell activated carbon catalyze the gasification of organic compounds in supercritical water. Feedstocks studied in this paper include glycerol, glucose, cellobiose, whole biomass feedstocks (depithed bagasse liquid extract and sewage sludge), and representative Department of Defense (DoD) wastes (methanol, methyl ethyl ketone, ethylene glycol, acetic acid, and phenol). The effects of temperature, pressure, reactant concentration, weight hourly space velocity, and the type of catalyst on the gasification of glucose are reported. Complete conversion of glucose (22% by weight in water) to a hydrogen-rich synthesis gas was realized at a weight hourly space velocity (WHSV) of 22.2 h-1 in supercritical water at 600 °C, 34.5 MPa. Complete conversions of the whole biomass feeds were also achieved at the same temperature and pressure. The destruction efficiencies for the representative DoD wastes were also high. Deactivation of the...

391 citations


Journal ArticleDOI
TL;DR: Comparisons between the diets of tiger sharks from Hawaii and other locations indicate that ontogenetic shifts are universal in this species and that tiger sharks may be opportunistic feeders that prey heavily on abundant, easy to capture prey.
Abstract: Stomach content data from 281 tiger sharks caught during shark control programs in Hawaii between 1967 and 1969, and during 1976 were analyzed to examine feeding habits and ontogenetic shifts in diet. As sharks increased in size, prey diversity and frequency of occurrence of large prey items increased. The percent occurrence of teleosts and cephalopods in stomachs decreased as sharks increased in length, while occurrence of elasmobranchs, turtles, land mammals, crustaceans, and undigestible items increased. Comparisons between the diets of tiger sharks from Hawaii and other locations indicate that ontogenetic shifts are universal in this species and that tiger sharks may be opportunistic feeders that prey heavily on abundant, easy to capture prey. Small tiger sharks may be spatially segregated from medium and large sharks and appear to be primarily nocturnal, bottom feeders. Large tiger sharks feed near the bottom at night, but also feed at the surface during the day. Prey, similar in size to humans, begin to occur in the diet of tiger sharks approximately 230 cm TL, and therefore sharks of this size and larger may pose the greatest threat to humans. Ontogenetic shifts in diet may be attributed to increased size of sharks, expanded range and exploitation of habitats of larger sharks, and/or improved hunting skill of larger sharks.

315 citations


Journal ArticleDOI
TL;DR: In this paper, three parameters are proposed to determine the relative extent of alteration in CM chondrites: the mineralogic alteration index monitors the relative progress of coupled substitutions in the progressive alteration of cronstedtite to Mg-serpentine and increases with increasing alteration.

297 citations


Journal ArticleDOI
TL;DR: The 1783-1784 Laki tholeiitic basalt fissure eruption in Iceland was one of the greatest atmospheric pollution events of the past 250 years, with widespread effects in the northern hemisphere.
Abstract: The 1783-1784 Laki tholeiitic basalt fissure eruption in Iceland was one of the greatest atmospheric pollution events of the past 250 years, with widespread effects in the northern hemisphere. The degassing history and volatile budget of this event are determined by measurements of pre-eruption and residual contents of sulfur, chlorine, and fluorine in the products of all phases of the eruption. In fissure eruptions such as Laki, degassing occurs in two stages: by explosive activity or lava fountaining at the vents, and from the lava as it flows away from the vents. Using the measured sulfur concentrations in glass inclusions in phenocrysts and in groundmass glasses of quenched eruption products, we calculate that the total accumulative atmospheric mass loading of sulfur dioxide was 122 Mt over a period of 8 months. This volatile release is sufficient to have generated approximately 250 Mt of H2SO4 aerosols, an amount which agrees with an independent estimate of the Laki aerosol yield based on atmospheric turbidity measurements. Most of this volatile mass (approximately 60 wt.%) was released during the first 1.5 months of activity. The measured chlorine and fluorine concentrations in the samples indicate that the atmospheric loading of hydrochloric acid and hydrofluoric acid was approximately 7.0 and 15.0 Mt, respectively. Furthermore, approximately 75% of the volatile mass dissolved by the Laki magma was released at the vents and carried by eruption columns to altitudes between 6 and 13 km. The high degree of degassing at the vents is attributed to development of a separated two-phase flow in the upper magma conduit, and implies that high-discharge basaltic eruptions such as Laki are able to loft huge quantities of gas to altitudes where the resulting aerosols can reside for months, or even 1-2 years. The atmospheric volatile contribution due to subsequent degassing of the Laki lava flow is only 18 wt.% of the total dissolved in the magma, and these emissions were confined to the lowest regions of the troposhere and therefore important only over Iceland. This study indicates that determination of the amount of sulfur degassed from the Laki magma batch by measurements of sulfur in the volcanic products (the petrologic method) yields a result which is sufficient to account for the mass of aerosols estimated by other methods.

290 citations


Journal ArticleDOI
TL;DR: Characterization of MAP kinase-mediated phosphorylation of connexin-43 has defined potential targets for phosphorylated in vivo following activation of the epidermal growth factor receptor and has provided the basis for studies of the effects of phosphorylate, at specific molecular sites, on the regulation of gap junctional communication.

Journal ArticleDOI
TL;DR: Spermatozoa do not need to be structurally intact for intracytoplasmic injection, the plasma and acrosomal membranes and all tail components are not essential for normal embryo development, at least in the mouse, and the cryopreservation conditions required for maintenance of the genetic integrity of sperm nuclei are less stringent than those necessary for keeping plasma membrane-intact spermatozoA alive.
Abstract: MATERIALS AND METHODS To determine whether spermatozoa must be structurally intact before microsurgical injection into oocytes for normal fertilization, intact spermatozoa, as well as sperm heads separated from tails by sonication, were individually injected into oocytes. When whole spermatozoa were injected immediately after their immobilization, the majority of the oocytes were fertilized and developed normally. Sonication in the presence or absence of Triton X-100 decapitated more than 95% of spermatozoa. Although all decapitated spermatozoa were diagnosed as "dead" by live/dead sperm staining, separated sperm heads (nuclei) could participate in normal embryo development when injected into the oocytes. The ability of isolated sperm heads (nuclei) to participate in normal embryo development was maintained under cryopreservation conditions that were not suitable for the survival of plasma membrane-intact spermatozoa. These results indicate that 1) spermatozoa do not need to be structurally intact for intracytoplasmic injection, 2) the plasma and acrosomal membranes and all tail components are not essential for normal embryo development, at least in the mouse, and 3) the cryopreservation conditions required for maintenance of the genetic integrity of sperm nuclei are less stringent than those necessary for keeping plasma membrane-intact spermatozoa alive.

Journal ArticleDOI
TL;DR: In this article, a new multiphase mixture model is proposed, in which the multiple phases are considered as constituents of a multi-phase mixture and the conservation equations are derived from the classic multiphases flow formulation without making any approximations.

Journal ArticleDOI
TL;DR: It turns out that in many cases most robots execute an identical, simple algorithm, and a method for controlling a group of mobile robots in a distributed manner is discussed.
Abstract: We discuss a method for controlling a group of mobile robots in a distributed manner. The method is distributed in the sense that all robots, or most of the robots in some cases, plan their motion individually based upon the given goal of the group and the observed positions of other robots. We illustrate the method by showing how a large number of robots can form an approximation of a circle, a simple polygon, or a line segment in the plane. We also show how the robots can distribute themselves nearly uniformly within a circle or a convex polygon in the plane. Finally, we show how the robots can be divided into two or more groups. It turns out that in many cases most robots execute an identical, simple algorithm. The performance of the method is demonstrated by simulation. © 1996 John Wiley & Sons, Inc.

Journal ArticleDOI
TL;DR: In this article, a multiscale/multiphase model for equiaxed dendritic solidification in the presence of melt convection and solid phase transport is proposed.
Abstract: Equiaxed dendritic solidification in the presence of melt convection and solid-phase transport is investigated in a series of three articles. In part I, a multiphase model is developed to predict com-position and structure evolution in an alloy solidifying with an equiaxed morphology. The model accounts for the transport phenomena occurring on the macroscopic (system) scale, as well as the grain nucleation and growth mechanisms taking place over various microscopic length scales. The present model generalizes a previous multiscale/multiphase model by including liquid melt convec-tion and solid-phase transport. The macroscopic transport equations for the solid and the interdendritic and extradendritic liquid phases are derived using the volume averaging technique and closed by supplementary relations to describe the interfacial transfer terms. In part II, a numerical application of the model to equiaxed dendritic solidification of an Al-Cu alloy in a rectangular cavity is dem-onstrated. Limited experimental validation of the model using a NH4C1-H2O transparent model alloy is provided in part III.

Journal ArticleDOI
TL;DR: In this paper, the authors comprehensively review the effects of solar ultraviolet radiation (UVR) on corals and other reef macroorganisms, mindful that although much is known of proximal effects, little of this knowledge is directly useful in making long-term predictions regarding the health of coral reefs.
Abstract: The discovery of the importance of solar ultraviolet radiation (UVR) as a factor affecting the biology of coral reefs dates only to about 1980. Interest has heightened during the past five years owing to the demonstration of loss of stratospheric ozone through human activities. We have only begun to document gross, qualitative effects of UVR on coral reef organisms, usually in experiments comparing the biological response to the presence or absence of UVR through the use of UV-cutoff filters, or to varying levels of UVR in transplantation studies. Most such studies have not distinguished between the effects of UVA (320–400 nm) and those of UVB (290–320 nm), although in the context of global change involving stratospheric ozone loss, it is the latter wavelengths that are relevant. To date we have been addressing physiological and ecological questions, not yet attempting to evaluate quantitatively the impact of forecast increases in solar UVB penetration. Interacting and synergistic effects of UVR with increased temperature, pollutants, sedimentation, visible light, etc. have scarcely been studied but will be essential to understanding and predicting the fate of coral reefs under conditions of global change. Here we comprehensively review the effects of UVR on corals and other reef macroorganisms, mindful that although much is known of proximal effects, little of this knowledge is directly useful in making long-term predictions regarding the health of coral reefs. We conclude that even small anthropogenic increases in UVB levels will have sublethal physiological manifestations in corals and other reef organisms, but that this will have relatively small impact on the distribution of reef corals and coral reefs, perhaps affecting their minimum depths of occurrence.

Journal ArticleDOI
01 Mar 1996-System
TL;DR: It is concluded that computer learning networks do have the potential to empower students when they are used appropriately, and some pedagogical suggestions for the effective use of computer networking in the second- and foreign-language classroom are provided.

Journal ArticleDOI
TL;DR: In this article, the authors used wavelet transform and waveform transform to analyze the temporal structure of the Southern Oscillation (50) and found that the principal period of the SO has experienced two rapid changes since 1872, one in the early 1910s and the other in the mid-1960s.
Abstract: Wavelet transforms (WLT) and waveform transforms (WFT) are effective tools that reveal temporal structure of nonstationary time series. The authors discuss principles and practical aspects of their geophysical applications. The WLT can display variance as a continuous function of time and frequency, but the frequency (time) locality reduces at the high (low) frequency bands. The WFT, on the other hand, provides a sharp view of the locality in both time and frequency, but presents variance by discrete base functions. The two techniques are complementary. The authors use both Morlet WLT and Gabor WFT to analyze temporal structure of the Southern Oscillation (50). The principal period of the SO has experienced two rapid changes since 1872, one in the early 1910s and the other in the mid-1960s. The dominant period was 3–4 years in the earliest four decades (1872–1910), 5–7 years in the ensuing five decades (1911–1960. except the 1920s), and about 5 years in the last two decades (1970–1992). Ale SO al...

Journal ArticleDOI
TL;DR: In this article, the authors used a one-dimensional mixed layer model to study the relationship between the rate of local precipitation and the mixed layer depth in the western tropical Pacific Ocean during the TOGA Coupled Ocean-Atmosphere Response Experiment.
Abstract: The broad, shallow body of warm (>29°C) water found in the western tropical Pacific Ocean plays an important role in the coupled ocean-atmosphere dynamics and thermodynamics associated with the El Nino-Southern Oscillation phenomenon. Thus, it is important to understand the processes that maintain and perturb that warm pool. Measurements from a buoy moored in the center of the warm pool during the TOGA Coupled Ocean-Atmosphere Response Experiment show that the exchange of mass between the ocean and atmosphere is as important as the exchange of heat. Rain forms a shallow, buoyant layer that does not mix with the water below except during infrequent strong wind events. Using a one-dimensional mixed layer model, it is demonstrated that the rate of local precipitation governs the mixed layer depth and can thus alter the rates of change in sea surface temperature during both warming and cooling periods. The observed mixed layer depth in the warm pool is at a depth that allows for maximum warming by ca...

Journal ArticleDOI
TL;DR: All vaccinated, protected Aotus monkeys produced antibodies which inhibited in vitro parasite growth, indicating that this assay may be a useful correlate of protective immunity and that immunity induced by BVp42 immunization is mediated, at least in part, by a direct effect of antibodies against the MSP-1 C-terminal region.
Abstract: The immunogenicity and protective efficacy of baculovirus recombinant polypeptide based on the Plasmodium falciparum merozoite surface protein 1 (MSP-1) has been evaluated in Aotus lemurinus griseimembra monkeys. The MSP-1-based polypeptide, BVp42, corresponds to the 42-kDa C-terminal processing fragment of the precursor molecule. Immunization of Aotus monkeys with BVp42 in complete Freund's adjuvant resulted in high antibody titers against the immunogen as well as parasite MSP-1. Fine specificity studies indicated that major epitopes recognized by these antibodies localize to conserved determinants of the 19-kDa C-terminal fragment derived from cleavage of the 42-kDa processing fragment. Effective priming of MSP-1-specific T cells was also demonstrated in lymphocyte proliferation assays. All three Aotus monkeys immunized with BVp42 in complete Freund's adjuvant showed evidence of protection of protection against blood-stage challenge with P. falciparum. Two animals were completely protected, with only one parasite being detected in thick blood films on a single days after injection. The third animal had a modified course of infection, controlling its parasite infection to levels below detection by thick blood smears for an extended period in comparison with adjuvant control animals. All vaccinated, protected Aotus monkeys produced antibodies which inhibited in vitro parasite growth, indicating that this assay may be a useful correlate of protective immunity and that immunity induced by BVp42 immunization is mediated, at least in part, by a direct effect of antibodies against the MSP-1 C-terminal region. The high level of protection obtained in these studies supports further development of BVp42 as a candidate malaria vaccine.

Book ChapterDOI
01 Jan 1996
TL;DR: In this paper, the distribution of carotenoids in different pigment proteins is reported showing that each photosystem subunit has its characteristic composition, and the organization of different xanthophylls within the antenna complexes is discussed on the basis of recent structural and biochemical evidence.
Abstract: Carotenoids are components of every pigment-protein complex in the photosynthetic apparatus of higher plants. These pigments, previously referred to as ‘accessory,’ are now recognized to fulfill indispensable functions in light harvesting, protection against photooxidation, and regulation of Photosystem II efficiency. The wealth of information accumulated in recent years dealing with the closely related questions of carotenoid organization and functions are summarized in this chapter. In the first section the distribution of carotenoids in the different pigment proteins is reported showing that each photosystem subunit has its characteristic composition. The organization of the different xanthophylls within the antenna complexes is discussed on the basis of recent structural and biochemical evidence. In the second section, advances in photophysical mechanisms through which carotenoids perform their classical light harvesting and protective functions are discussed. In addition, particular attention is given to discussion of the xanthophyll cycle which, in conjunction with the transthylakoid ΔpH1 down-regulates Photosystem II photochemical efficiency by non-radiative dissipation of energy in the light-harvesting complexes. Down-regulation helps to keep PS II traps open, thereby helping to maintain electron transport and to protect the reaction center from photoinhibition.

Journal ArticleDOI
TL;DR: In this article, sugar-cane bagasse and leaves (10−15 g oven-dry basis) were fractionated without size reduction by a rapid (45 s to 4 min), immersed percolation using only hot (190−230 °C), compressed (P > Psat), liquid water (0.6−1.2 kg).
Abstract: Sugar-cane bagasse and leaves (10−15 g oven-dry basis) were fractionated without size reduction by a rapid (45 s to 4 min), immersed percolation using only hot (190−230 °C), compressed (P > Psat), liquid water (0.6−1.2 kg). Over 50% of the biomass could be solubilized. All of the hemicellulose, together with much of the acid-insoluble lignin in the bagasse (>60%), was solubilized, while less than 10% of the cellulose entered the liquid phase. Moreover, recovery of the hemicellulose as monomeric sugars (after a mild posthydrolysis) exceeded 80%. Less than 5% of the hemicellulose was converted to furfural. Percolation beyond that needed to immerse the biomass in hot liquid water did not result in increased solubilization. The yield of lignocellulosic residue was also not sensitive to the form of the sugar cane used (bagasse or leaves) or its moisture content (8−50%). Commercial applications for this fractionation process include the pretreatment of lignocellulosics for bioconversion to ethanol and the produ...

Journal ArticleDOI
04 Oct 1996-Science
TL;DR: In this article, a simple paradigm of the tropical climate system is presented, capturing the basic physics of these two important aspects of the tropic Pacific and basic features of the climate states of the Atlantic and Indian ocean basins.
Abstract: The tropical Pacific basin allows strong feedbacks among the trade winds, equatorial zonal sea surface temperature contrast, and upper ocean heat content. Coupled atmosphere-ocean dynamics produce both the strong Pacific cold tongue climate state and the El Nino-Southern Oscillation phenomenon. A simple paradigm of the tropical climate system is presented, capturing the basic physics of these two important aspects of the tropic Pacific and basic features of the climate states of the Atlantic and Indian ocean basins.

Journal ArticleDOI
TL;DR: In this paper, eight types of agricultural and forest fuels including 4 cereal crop residues and 4 wood fuels were burned in a combustion wind tunnel to simulate the open burning of biomass, and concentrations for 19 PAH species in particulate matter were found to range between 120 and 4000 mg kg−1, representing between 1 and 70% of total PAH emission.

Journal ArticleDOI
TL;DR: Agarwal et al. as discussed by the authors have conducted petrologic, chemical, and isotopic studies of acapulcoites (Acapulco, Monument Draw, Yamato 74063, ALH A77081, Alh A81261, AlH A81315, AL H 78230, AL A81187 and ALH 84190) in an attempt to constrain their genesis.

Journal ArticleDOI
TL;DR: In this paper, an intermediate coupled model for the El Nino/Southern Oscillation (ENSO) phenomenon is used to examine the interaction of ENSO with the seasonal cycle and how this is related to the irregularity of the time series.

Journal ArticleDOI
TL;DR: The authors identify some of the salient conceptual and methodological issues involved in cross-cultural research, and then explore and elaborate on these issues in greater detail by investigating principal leadership across two cultural settings.
Abstract: Notes that, while there have been periodic calls for comparative work in educational administration, few empirical studies have been designed specifically to compare principal leadership practices between contextual and cultural settings. Suggests that conducting such studies raises several conceptual and methodological problems with respect to underlying assumptions about knowledge, appropriate conceptualizations of principal leadership, and methods of inquiry. Proposes first to identify some of the salient conceptual and methodological issues involved in cross‐cultural research, and then to explore and elaborate on these issues in greater detail by investigating principal leadership across two cultural settings.

Journal ArticleDOI
TL;DR: The short and long-term movement patterns of blue trevally (Caranx melampygus) were monitored using a combination of sonic tracking and tag-and-release techniques.

Journal ArticleDOI
TL;DR: In this paper, a numerical model for endothermic biomass pyrolysis, which includes both high activation energy kinetics and heat transfer across a boundary layer to the reacting solid particle, is presented.
Abstract: Results from a numerical model for endothermic biomass pyrolysis, which includes both high activation energy kinetics and heat transfer across a boundary layer to the reacting solid particle, are presented. The model accounts for conventional thermocouple thermal lag and unconventional thermal lag due to heat demand by the chemical reaction (which is governed by Arrhenius kinetics). Biomass fusion, first identified quantitatively by Lede and Villermaux, is shown to be a manifestation of severe thermal lag that results from the chemical reaction heat demand. Over the wide range of conditions studied, the true substrate temperature remains almost constant during pyrolysis, as is the case with compounds undergoing fusion or sublimation at constant pressure. A simple algebraic model, whose derivation presupposes the idea that biomass pyrolysis mimics the melting of a block of ice, accurately predicts the maximum value of thermal lag during pyrolysis. Unidentified thermal lag in TGA experiments lowers the valu...

Journal ArticleDOI
TL;DR: In this article, the authors show that exposure and lithology, rather than the climatic variables, temperature, and runoff, dominate the weathering yields in active orogenic belts.