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1997

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A Vegetation Based Approach To Biodiversity Gap Analysis In The Agastyamalai Region, Western Ghats, India, B. R. Ramesh, Shaily Menon, Kamaljit S. Bawa Nov 1997

A Vegetation Based Approach To Biodiversity Gap Analysis In The Agastyamalai Region, Western Ghats, India, B. R. Ramesh, Shaily Menon, Kamaljit S. Bawa

Shaily Menon

Protected areas in India have historically been established on an ad hoc basis with little attention to the conservation value of an area. This study focuses on a set of protected areas in the Agastyamalai region of the Western Ghats (WG), India. We examine forest loss and land-use changes in the study area from the early 1900s to 1960 and from 1960 to 1990. We use GIS to perform a biodiversity gap analysis of the protected areas in the study site. We produce a detailed map of existing floristic types and use it to generate layers corresponding to floristic species …


Egg Removal By Brown-Headed Cowbirds: A Field Test Of The Host Incubation Efficiency Hypothesis, Douglas R. Wood, Eric K. Bollinger Nov 1997

Egg Removal By Brown-Headed Cowbirds: A Field Test Of The Host Incubation Efficiency Hypothesis, Douglas R. Wood, Eric K. Bollinger

Eric K. Bollinger

Brown-headed Cowbirds (Molothrus ater) often remove host eggs, usually to the detriment of the host's reproductive success. We tested the hypothesis that host egg size and number influence the incubation efficiency of a parasitic egg. A single House Sparrow (Passer domesticus) or Brown-headed Cowbird egg was placed in each host nest (addition), and in some nests a host egg was removed as well (addition/removal). Hatching success and incubation length were measured to determine whether host-egg removal conferred an advantage in incubation efficiency compared to simple addition of a parasitic egg. Redwinged Blackbirds (Agelaius phoeniceus) and Chipping Sparrows (Spizella passerina) served …


Evolutionary Genetics And Genetic Variation Of Haplodiploids And X-Linked Genes, Philip W. Hedrick, Joel D. Parker Nov 1997

Evolutionary Genetics And Genetic Variation Of Haplodiploids And X-Linked Genes, Philip W. Hedrick, Joel D. Parker

Joel D Parker

The evolutionary genetics of haplodiploids and X-linked genes share many features and are different from diploid (autosomal) genes in many respects. For example, the conditions for a stable polymorphism, the amount of genetic load, and the effective population size are all expected to be quite different between haplodiploids or X-linked genes and diploids. From experimental data, the genetic load for X-linked genes is much less than autosomal genes and appears less for haplodiploids than for diploids. The observed amount of molecular variation for haplodiploids is much less than that for diploids, even more so than predicted from the differences in …


Reinvigorating Introductory Biology: A Theme-Based, Investigative Approach To Teaching Biology Majors, Cynthia Norton, Lynne H. Gildensoph, Martha Phillips, Deborah Wygal, Kurt Olson, John Pellegrini, Kathleen Tweeten Oct 1997

Reinvigorating Introductory Biology: A Theme-Based, Investigative Approach To Teaching Biology Majors, Cynthia Norton, Lynne H. Gildensoph, Martha Phillips, Deborah Wygal, Kurt Olson, John Pellegrini, Kathleen Tweeten

Kurt Olson

No abstract provided.


Signal Transduction: Rhomantic Interludes Raise Blood Pressure, Andrew P. Somlyo Oct 1997

Signal Transduction: Rhomantic Interludes Raise Blood Pressure, Andrew P. Somlyo

Jama S. Coartney

No abstract provided.


Sequential Expression Of Egr-1 And Egr-3 In Hippocampal Granule Cells Following Electroconvulsive Stimulation, Kevin O'Donovan Oct 1997

Sequential Expression Of Egr-1 And Egr-3 In Hippocampal Granule Cells Following Electroconvulsive Stimulation, Kevin O'Donovan

Kevin O'Donovan

No abstract provided.


Energetics Of Swimming By The Platypus Ornithorhynchus Anatinus: Metabolic Effort Associated With Rowing, Frank E. Fish, R V. Baudinette, P B. Frappell, M P. Sarre Oct 1997

Energetics Of Swimming By The Platypus Ornithorhynchus Anatinus: Metabolic Effort Associated With Rowing, Frank E. Fish, R V. Baudinette, P B. Frappell, M P. Sarre

Frank E. Fish

The metabolism of swimming in the platypus Ornithorhynchus anatinus Shaw was studied by measurement of oxygen consumption in a recirculating water flume. Platypuses swam against a constant water current of 0.45-1.0ms(-1). Animals used a rowing stroke and alternated bouts of surface and submerged swimming. Metabolic rate remained constant over the range of swimming speeds tested. The cost of transport decreased with increasing velocity to a minimum of 0.51 at 1.0ms(-1) Metabolic rate and cost of transport for the platypus were lower than values for semiaquatic mammals that swim at the water surface using a paddling mode. However, relative to transport …


Spiroplasma Lineolae Sp. Nov., From The Horsefly Tabanus Lineola (Diptera : Tabanidae), Frank E. French, Robert F. Whitcomb, Joseph G. Tully, Patricia Carle, Joseph M. Bové, Roberta B. Henegar, Jean R. Adams, Gail E. Gasparich, David L. Williamson Sep 1997

Spiroplasma Lineolae Sp. Nov., From The Horsefly Tabanus Lineola (Diptera : Tabanidae), Frank E. French, Robert F. Whitcomb, Joseph G. Tully, Patricia Carle, Joseph M. Bové, Roberta B. Henegar, Jean R. Adams, Gail E. Gasparich, David L. Williamson

Gail Gasparich

Spiroplasma strain TALS-2T from the viscera of the striped horsefly, Tabanus lineola, collected in Georgia was serologically distinct from other Spiroplasma species, groups, putative groups, and subgroups. Light and electron microscopy of cells of strain TALS-2T revealed helical motile cells surrounded only by a single cytoplasmic membrane. The organism grew in M1D and SP-4 liquid media. Growth also occurred in 1% serum fraction medium and in conventional horse serum medium. Growth in liquid media was serum dependent. The strain passed through 220-nm filter pores, but was retained in filters with 100-nm pores. The optimum temperature for growth was 30°C. Multiplication …


Collaborative Roles For C-Jun N-Terminal Kinase, C-Jun, Serum Response Factor, And Sp1 In Calcium-Regulated Myocardial Gene Expression, Patrick M. Mcdonough, Deanna S. Hanford, Amy B. Sprenkle, Noel R. Mellon, Christopher C. Glembotski Sep 1997

Collaborative Roles For C-Jun N-Terminal Kinase, C-Jun, Serum Response Factor, And Sp1 In Calcium-Regulated Myocardial Gene Expression, Patrick M. Mcdonough, Deanna S. Hanford, Amy B. Sprenkle, Noel R. Mellon, Christopher C. Glembotski

Amy Sprenkle

Electrical stimulation of contractions (pacing) of primary neonatal rat ventricular myocytes increases intracellular calcium and activates a hypertrophic growth program that includes expression of the cardiac-specific gene, atrial natriuretic factor (ANF). To investigate the mechanism whereby pacing increases ANF, pacing was tested for its ability to regulate mitogen-activated protein kinase family members, ANF promoter activity, and the trans-activation domain of the transcription factor, Sp1. Pacing and the calcium channel agonist BAYK 8644 activated c-Jun N-terminal kinase (JNK) but not extracellular signal-regulated kinase. Pacing stimulated ANF-promoter activity approximately 10-fold. Furthermore, transfection with an expression vector for c-Jun, a substrate for JNK, …


Iron Regulatory Protein 1 Is Not Required For The Modulation Of Ferritin And Transferrin Receptor Expression By Iron In A Murine Pro-B Lymphocyte Cell Line, Kevin Schalinske, Kenneth P. Blemings, Daniel W. Steffen, Opal S. Chen, Richard S. Eisenstein Sep 1997

Iron Regulatory Protein 1 Is Not Required For The Modulation Of Ferritin And Transferrin Receptor Expression By Iron In A Murine Pro-B Lymphocyte Cell Line, Kevin Schalinske, Kenneth P. Blemings, Daniel W. Steffen, Opal S. Chen, Richard S. Eisenstein

Kevin Schalinske

Iron regulatory proteins (IRPs) are cytoplasmic RNA binding proteins that are central components of a sensory and regulatory network that modulates vertebrate iron homeostasis. IRPs regulate iron metabolism by binding to iron responsive element(s) (IREs) in the 5* or 3* untranslated region of ferritin or transferrin receptor (TfR) mRNAs. Two IRPs, IRP1 and IRP2, have been identified previously. IRP1 exhibits two mutually exclusive functions as an RNA binding protein or as the cytosolic isoform of aconitase. We demonstrate that the BayF3 family of murine pro-B lymphocytes represents the first example of a mammalian cell line that fails to express IRP1 …


Comparison Of Risk/Hazard Rating Systems For Mountain Pine Beetle In Black Hills Ponderosa Pine Forests, Judith Pasek, Thomas Juntti Jul 1997

Comparison Of Risk/Hazard Rating Systems For Mountain Pine Beetle In Black Hills Ponderosa Pine Forests, Judith Pasek, Thomas Juntti

Judith E Pasek

Risk/hazard rating methods for mountain pine beetle (MPB) in ponderosa pine stands were compared, based upon number of stands and acres that rated as low, medium or high risk/hazard, for four recent project areas on the Black Hills National Forest. Methods compared were the (1) Stevens model described by Stevens et al. (1980) except that the basal area threshold for high susceptibility was reduced from 150 to 120 based upon results of Schmid and Mata (1992), (2) FORPLAN model used in the Draft Revised Black Hills National Forest Plan (same as Stevens model except for assumption of only one-storied stand …


Ms2 Coat Protein Mutants Which Bind Qβ Rna, Marc Spingola, David S. Peabody Jul 1997

Ms2 Coat Protein Mutants Which Bind Qβ Rna, Marc Spingola, David S. Peabody

Marc Spingola

The coat proteins of the RNA phages MS2 and Qβ are structurally homologous, yet they specifically bind different RNA structures. In an effort to identify the basis of RNA binding specificity we sought to isolate mutants that convert MS2 coat protein to the RNA binding specificity of Qβ. A library of mutations was created which selectively substitutes amino acids within the RNA binding site. Genetic selection for the ability to repress translation from the Qβ translational operator led to the isolation of several MS2 mutants that acquired binding activity for Qβ RNA. Some of these also had reduced abilities to …


Applications Of Geographic Information Systems, Remote-Sensing, And A Landscape Ecology Approach To Biodiversity Conservation In The Western Ghats, Shaily Menon, Kamaljit S. Bawa Jun 1997

Applications Of Geographic Information Systems, Remote-Sensing, And A Landscape Ecology Approach To Biodiversity Conservation In The Western Ghats, Shaily Menon, Kamaljit S. Bawa

Shaily Menon

The mountains along the west coast of peninsular India, the Western Ghats, constitute one of the unique biological regions of the world. Rapidly occurring land-cover and land-use change in the Western Ghats has serious implications for the biodiversity of the region. Both landscape changes as well as the distribution of biodiversity are phenomena with strong spatial correlates. Recent developments in remote-sensing technology and Geographic Information Systems (GIS) allow the use of a landscape ecology and spatial analysis approach to the problem of deforestation and biodiversity conservation in the Western Ghats. Applications of this approach include analyses of land-cover and land-use …


Spiroplasma Chrysopicola Sp. Nov., Spiroplasma Gladiatoris Sp. Nov., Spiroplasma Helicoides Sp. Nov., And Spiroplasma Tabanidicola Sp. Nov., From Tabanid (Diptera: Tabanidae) Flies, Robert F. Whitcomb, Frank E. French, Joseph G. Tully, Gail E. Gasparich, David L. Rose, Patricia Carle, Joseph M. Bove, Roberta B. Henegar, Meghnad Konai, Kevin J. Hackett, Jean R. Adams, Truman B. Clark, David L. Williamson Jun 1997

Spiroplasma Chrysopicola Sp. Nov., Spiroplasma Gladiatoris Sp. Nov., Spiroplasma Helicoides Sp. Nov., And Spiroplasma Tabanidicola Sp. Nov., From Tabanid (Diptera: Tabanidae) Flies, Robert F. Whitcomb, Frank E. French, Joseph G. Tully, Gail E. Gasparich, David L. Rose, Patricia Carle, Joseph M. Bove, Roberta B. Henegar, Meghnad Konai, Kevin J. Hackett, Jean R. Adams, Truman B. Clark, David L. Williamson

Gail Gasparich

Four spiroplasma strains, DF-1T, TG-1T, TABS-2T, and TAUS-1T, all of which were isolated from deerflies or horseflies (Diptera: Tabanidae), were serologically distinct from previously described spiroplasma species, groups, and subgroups. Strain DF-1Toriginated from a Maryland deerfly (Chrysops sp.); strain TG-1Twas isolated from a Maryland horsefly (Tabanus gladiator); strain TAUS-1Toriginated from a member of the Tabanus abdominalis-limbatinevris complex of horseflies collected in Maryland; and strain TABS-2Twas isolated from a horsefly (Tabanus abactor) collected in Oklahoma. Cells of all of the strains appeared to be helical and motile when they were examined by dark-field microscopy. Cells of strain DF-1Tgrowing in M1D medium …


Use Of Ultimate Load Theories For Design Of Drilled Shaft Sound Wall Foundations, Matthew J. Helmers Jun 1997

Use Of Ultimate Load Theories For Design Of Drilled Shaft Sound Wall Foundations, Matthew J. Helmers

Matthew J. Helmers

A study was performed to investigate the factors that affect the accuracy of the procedures used by the Virginia Department of Transportation for design of drilled shaft sound wall foundations. Field load tests were performed on eight inch and nine inch diameter drilled shafts, and the results were compared to theoretical solutions for ultimate lateral load capacity. Standard Penetration Tests were run in the field and laboratory strength tests were performed on the soils from the test sites. It was found that published correlations between blow count and friction angle for sands and gravels can be used to estimate friction …


Predicting Modes Of Toxic Action From Chemical Structure: Acute Toxicity In The Fathead Minnow (Pimephales Promelas), Steven P. Bradbury, Christine L. Russom, Steven J. Broderius, Dean E. Hammermeister, Robert A. Drummond May 1997

Predicting Modes Of Toxic Action From Chemical Structure: Acute Toxicity In The Fathead Minnow (Pimephales Promelas), Steven P. Bradbury, Christine L. Russom, Steven J. Broderius, Dean E. Hammermeister, Robert A. Drummond

Steven P. Bradbury

In the field of aquatic toxicology, quantitative structure-activity relationships (QSARs) have developed as scientifically credible models for predicting the toxicity of chemicals when little or no empirical data are available. In recent years, there has been an evolution of QSAR development and application from that of a chemical-class perspective to one that is more consistent with assumptions regarding modes of toxic action. The objective of this research was to develop procedures that relate modes of acute toxic action in the fathead minnow (Pimephales promelas) to chemical structures and properties. An empirically derived database for diverse chemical structures of acute toxicity …


Ac-Mode Atomic Force Microscope Imaging In Air And Solutions With A Thermally Driven Bimetallic Cantilever Probe, Andrew C. Hillier, Allen J. Bard Apr 1997

Ac-Mode Atomic Force Microscope Imaging In Air And Solutions With A Thermally Driven Bimetallic Cantilever Probe, Andrew C. Hillier, Allen J. Bard

Andrew C. Hillier

An ac imaging mode for atomic force microscopy ~AFM! has been developed that employs a thermally driven bimetallic cantilever to sense surface topography. Oscillations are induced in a composite cantilever, comprising a Si3N4 layer and Au overcoat, by local heating with a resistive wire heater placed in close proximity to the cantilever. Cantilever bending occurs upon heating due to the difference in thermal expansion coefficients of the Si3N4 and Au layers. The magnitude of this bending is a function of the heat input, the cantilever geometry, the frequency of the excitation, and the thermal properties of the surrounding medium. A …


Opercular Jetting During Fast-Starts By Flatfishes, E L. Brainerd, B N. Page, Frank E. Fish Apr 1997

Opercular Jetting During Fast-Starts By Flatfishes, E L. Brainerd, B N. Page, Frank E. Fish

Frank E. Fish

When attacked by predators, flatfishes perform fast-starts that result in a rapid take-off from the ocean bottom on which they lie. High-speed video recordings of the blind side of flatfishes indicate that they expel a coherent jet of water from the blind-side opercular valve during take-off. Buccal pressure recordings in winter flounder (Pseudopleuronectes americanus) show that a buccal pressure pulse begins 0-20 ms before the beginning of the fast-start and has a range of mean magnitudes for three individuals of 1.6-10.7 kPa. We hypothesize that one function of the opercular jet in flatfishes may be to reduce the effects of …


Acute Toxicity And Behavioral Effects Of Chlorpyrifos, Permethrin, Phenol, Strychnine, And 2,4-Dinitrophenol To 30-Day-Old Japanese Medaka (Oryzias Latipes), Steven P. Bradbury, Patricia J. Rice, Charles D. Drewes, Theresa M. Klubertanz, Joel R. Coats Apr 1997

Acute Toxicity And Behavioral Effects Of Chlorpyrifos, Permethrin, Phenol, Strychnine, And 2,4-Dinitrophenol To 30-Day-Old Japanese Medaka (Oryzias Latipes), Steven P. Bradbury, Patricia J. Rice, Charles D. Drewes, Theresa M. Klubertanz, Joel R. Coats

Steven P. Bradbury

Five chemicals with different modes of action were evaluated in laboratory studies to determine their acute toxicity (48-h median lethal concentration [LC50]) and behavioral effects on 30-d-old Japanese medaka (Oryzias latipes). The order of toxicity for these xenobiotics was permethrin > chlorpyrifos > 2,4-dinitrophenol (2,4-DNP) > strychnine > phenol. The 48-h LC50s were significantly different and ranged from 0.011 to 24.1 mg/L. In addition, chlorpyrifos and permethrin accumulated in the tissues of juvenile O. latipes. Observations of five behavioral/morphological responses, including changes in equilibrium, general activity, startle response, and morphology (e.g., hemorrhage and deformities) were used as indicators of sublethal toxicity. Each chemical, with …


Internet Childhood Safety And Health Resource Guide, Steven A. Freeman, Scott D. Whitman, Roger L. Tormoehlen, Karla M. Embleton Apr 1997

Internet Childhood Safety And Health Resource Guide, Steven A. Freeman, Scott D. Whitman, Roger L. Tormoehlen, Karla M. Embleton

Steven A. Freeman

Purdue University's Agricultural Safety and Health Program, historically a paper-based directory of childhood safety and health resources, is now available on the World Wide Web (WWW). Advantages to WWW publication include: widespread availability, continuous updates, and low distribution costs. Disadvantages include: lack of acceptance by some Extension clientele, loss of portability, and initial difficulties in finding the publication's WWW location. The use of on-line resources has been moderate to date. However, a significant increase in utilization is expected as Internet access becomes less expensive and Extension educators and external clientele become more accustomed to using on-line resources.


Emergence And Overwintering Brood Of Douglas-Fir Beetle Eight Years After The Clover Mist Fire On The Clarks Fork Ranger District, Shoshone National Forest, Wyoming, Kurt K. Allen Mar 1997

Emergence And Overwintering Brood Of Douglas-Fir Beetle Eight Years After The Clover Mist Fire On The Clarks Fork Ranger District, Shoshone National Forest, Wyoming, Kurt K. Allen

Judith E Pasek

The Douglas-fir beetle outbreak on the Shoshone National Forest is evaluated for the eighth consecutive year. Adult emergence in 1996 showed a single peak. Overwintering brood in 1996 were used to predict population levels for 1997. Brood levels declined from 1995 but 81% of the overwintering brood are adults. Damage levels (number of trees killed) was at its lowest point in the last 7 years, a 4.5 fold decline from 1995. Brood counts indicate a steady or slight increase in beetle populations; however, in most areas suitable host trees are becoming scarce.

Management alternatives include salvage and sanitation, tree baiting, …


Explanations For The Infrequent Cowbird Parasitism On Common Grackles, Brian D. Peer, Eric K. Bollinger Feb 1997

Explanations For The Infrequent Cowbird Parasitism On Common Grackles, Brian D. Peer, Eric K. Bollinger

Eric K. Bollinger

We determined the factors responsible for the lack of parasitism on Common Grackles (Quiscalus quiscula) by Brown-headed Cowbirds (Molothrus ater). We found no evidence of parasitism on the 401 grackle nests we monitored in east-central Illinois. By the time cowbirds began laying eggs, 88.5% of all grackle nests were beyond the point of successful parasitism. Grackles rejected cowbird eggs more frequently during the prelaying stage of the nesting cycle (38.2%) compared to later stages (12.3%). Thirty-three cowbird eggs and nestlings were cross-fostered into grackle nests. Data were collected on 15 cowbird nestlings, of which three fledged. The cross-fostered cowbird eggs …


Strategies, Policy Approaches, And Resources For Local Food System Planning And Organizing, Kenneth Dahlberg, Kate Clancy, Robert L. Wilson, Jan O'Donnell Jan 1997

Strategies, Policy Approaches, And Resources For Local Food System Planning And Organizing, Kenneth Dahlberg, Kate Clancy, Robert L. Wilson, Jan O'Donnell

Kenneth Dahlberg

No abstract provided.


Comparative Leaf Anatomy And Systematics In Dendrobium, Sections Aporum And Rhizobium (Orchidaceae), Barbara S. Carlsward, William Lois Stern, Walter S. Judd, Terence W. Lucansky Jan 1997

Comparative Leaf Anatomy And Systematics In Dendrobium, Sections Aporum And Rhizobium (Orchidaceae), Barbara S. Carlsward, William Lois Stern, Walter S. Judd, Terence W. Lucansky

Barbara S. Carlsward

The specialized leaf anatomy for species of Dendrobium within section Aporum is similar to that of species in section Rhizobium. In both sections leaves are characterized by a unifacial or nearly unifacial surface where the exposed surface is abaxial. However, leaves in section Rhizobium also feature a lacuna submerged in the mesophyll and surrounded by an adaxial epidermis. In contrast, leaves in section Aporum merely present an internal suture that divides the leaf into bilateral halves. These two sections of Dendrobium are hypothesized to be sister taxa because of synapomorphies in their foliar anatomy. A cladistic analysis performed with various …


Selective Predation On The Seeds Of Woody Plants, Scott J. Meiners, Edmund W. Stiles Jan 1997

Selective Predation On The Seeds Of Woody Plants, Scott J. Meiners, Edmund W. Stiles

Scott J. Meiners

Selective predation on the seeds of woody plants. J. Torrey Bot. Soc. 124: 67-70). 1997.-Seed predation may be an important factor influencing the structure of successional plant communities. We used a cafeteria-style experiment, placed in an old field and an early successional forest, to determine predator preferences for seeds of nine species of woody plants. Intensity of seed predation was equivalent in both sites. Seed predators preferred Acer saccharum, flex vertic illata, and Viburnum dentatum, but this was not related to seed mass. Predation intensity was more variable in the old field than in the forest, possibly related to the …


Crows Do Not Use Automobiles As Nutcrackers: Putting An Oft-Repeated Anecdote To The Test, Daniel A. Cristol, Paul V. Switzer, K L. Johnson, L S. Walke Jan 1997

Crows Do Not Use Automobiles As Nutcrackers: Putting An Oft-Repeated Anecdote To The Test, Daniel A. Cristol, Paul V. Switzer, K L. Johnson, L S. Walke

Paul V. Switzer

No abstract provided.


Comparison Of The Aquatic Ecology Of Side-Canyons And The Main Channel Of Lake Powell 1997, Wayne A. Wurtsbaugh Jan 1997

Comparison Of The Aquatic Ecology Of Side-Canyons And The Main Channel Of Lake Powell 1997, Wayne A. Wurtsbaugh

Wayne A. Wurtsbaugh

Physical characteristics of lakes are highly interrelated with biological characteristics. We measured and analyzed the physical characteristics of two side canyons in order to better understand differences in productivity between side canyons and the main channel and to provide general information on the characteristics of the lake.


Discovery And Classification Of Ecological Diversity In The Bacterial World: The Role Of Dna Sequence Data, T. Palys, L. Nakamura, Frederick Cohan Jan 1997

Discovery And Classification Of Ecological Diversity In The Bacterial World: The Role Of Dna Sequence Data, T. Palys, L. Nakamura, Frederick Cohan

Frederick M. Cohan

No abstract provided.


The Brain As A Symbol-Processing Machine., Armando F. Rocha Jan 1997

The Brain As A Symbol-Processing Machine., Armando F. Rocha

Armando F Rocha

The knowledge accumulated about the biochemistry of the synapsis in the last decades completely changes the notion of brain processing founded exclusively over an electrical mechanism, toward that supported by a complex chemical message exchange occurring both locally, at the synaptic site, as well as at other localities, depending on the solubility of the involved chemical substances in the extracellular compartment. These biochemical transactions support a rich symbolic processing of the information both encoded by the genes and provided by actual data collected from the surrounding environment, by means of either special molecular or cellular receptor systems. In this processing, …


Hadhramaut And The Hadhrami Diaspora: Problems In Theoretical History, Syed Farid Alatas Jan 1997

Hadhramaut And The Hadhrami Diaspora: Problems In Theoretical History, Syed Farid Alatas

farid alatas

If we understand history as a field constituted by a type of research and inquiry that concerns itself with human action in the past and is based on the interpretation of evidence, regardless of whether positivist or interpretive methods are used, then it can be said that historical works on Hadhramaut and its diaspora have been written. These works can be divided in broad terms into the two general categories of Arab and Western historiography. Nevertheless, in both cases, owing to certain theoret- ical problems that have beset these works, little progress has been made in the advancement of Hadhrami …