bluuebunny/crossref_metadata_2025 huggingface dataset:
Conceptual bases for quantifying the role of the environment on gene evolution: the participation of positive selection and neutral evolution
Authors: Levasseur Anthony , Orlando Ludovic , Bailly Xavier , Milinkovitch Michel C. , Danchin Etienne G. J. , Pontarotti Pierre
Published: October 2007

To demonstrate that a given change in the environment has contributed to the emergence of a given genotypic and phenotypic shift during the course of evolution, one should ask to what extent such shifts would have occurred without environmental change. Of course, such tests are rarely practical but phenotypic novelties can still be correlated to genomic shifts in response to environmental changes if enough information is available. We surveyed and re‐evaluated the published data in order to estimate the role of environmental changes on the course of species and genomic evolution. Only a few published examples clearly demonstrate a causal link between a given environmental change and the fixation of a genomic variant resulting in functional modification (gain, loss or alteration of function). Many others suggested a link between a given phenotypic shift and a given environmental change but failed to identify the underlying genomic determinant(s) and/or the associated functional consequence(s).

The proportion of genotypic and phenotypic variation that is fixed concomitantly with environmental changes is often considered adaptive and hence, the result of positive selection, even though alternative causes, such as genetic drift, are rarely investigated. Therefore, the second aim herein is to review evidence for the mechanisms leading to fixation.
The Role of Frugivorous Bats in Tropical Forest Succession
Authors: Muscarella Robert , Fleming Theodore H.
Published: October 2007

Discussion of successional change has traditionally focused on plants. The role of animals in producing and responding to successional change has received far less attention. Dispersal of plant propagules by animals is a fundamental part of successional change in the tropics. Here we review the role played by frugivorous bats in successional change in tropical forests. We explore the similarities and differences of this ecological service provided by New and Old World seed‐dispersing bats and conclude with a discussion of their current economic and conservation implications. Our review suggests that frugivorous New World phyllostomid bats play a more important role in early plant succession than their Old World pteropodid counterparts. We propose that phyllostomid bats have shared a long evolutionary history with small‐seeded early successional shrubs and treelets while pteropodid bats are principally dispersers of the seeds of later successional canopy fruits. When species of figs (Ficus) are involved in the early stages of primary succession (e.g. in the river meander system in Amazonia and on Krakatau, Indonesia), both groups of bats are important contributors of propagules. Because they disperse and sometimes pollinate canopy trees, pteropodid bats have a considerable impact on the economic value of Old World tropical forests; phyllostomid bats appear to make a more modest direct contribution to the economic value of New World tropical forests. Nonetheless, because they critically influence forest regeneration, phyllostomid bats make an important indirect contribution to the economic value of these forests. Overall, fruit‐eating bats play important roles in forest regeneration throughout the tropics, making their conservation highly desirable.
Effect size, confidence interval and statistical significance: a practical guide for biologists
Authors: Nakagawa Shinichi , Cuthill Innes C.
Published: October 2007

Null hypothesis significance testing (NHST) is the dominant statistical approach in biology, although it has many, frequently unappreciated, problems. Most importantly, NHST does not provide us with two crucial pieces of information: (1) the magnitude of an effect of interest, and (2) the precision of the estimate of the magnitude of that effect. All biologists should be ultimately interested in biological importance, which may be assessed using the magnitude of an effect, but not its statistical significance. Therefore, we advocate presentation of measures of the magnitude of effects (i.e. effect size statistics) and their confidence intervals (CIs) in all biological journals. Combined use of an effect size and its CIs enables one to assess the relationships within data more effectively than the use ofpvalues, regardless of statistical significance. In addition, routine presentation of effect sizes will encourage researchers to view their results in the context of previous research and facilitate the incorporation of results into future meta‐analysis, which has been increasingly used as the standard method of quantitative review in biology. In this article, we extensively discuss two dimensionless (and thus standardised) classes of effect size statistics:dstatistics (standardised mean difference) andrstatistics (correlation coefficient), because these can be calculated from almost all study designs and also because their calculations are essential for meta‐analysis. However, our focus on these standardised effect size statistics does not mean unstandardised effect size statistics (e.g. mean difference and regression coefficient) are less important. We provide potential solutions for four main technical problems researchers may encounter when calculating effect size and CIs: (1) when covariates exist, (2) when bias in estimating effect size is possible, (3) when data have non‐normal error structure and/or variances, and (4) when data are non‐independent. Although interpretations of effect sizes are often difficult, we provide some pointers to help researchers. This paper serves both as a beginner’s instruction manual and a stimulus for changing statistical practice for the better in the biological sciences.
Morphologic changes associated with functional adaptation of the navicular bone of horses
Authors: Bentley V. A. , Sample S. J. , Livesey M. A. , Scollay M. C. , Radtke C. L. , Frank J. D. , Kalscheur V. L. , Muir P.
Published: October 2007

Failure of functional adaptation to protect the skeleton from damage is common and is often associated with targeted remodeling of bone microdamage. Horses provide a suitable model for studying loading‐related skeletal disease because horses are physically active, their exercise is usually regulated, and adaptive failure of various skeletal sites is common. We performed a histologic study of the navicular bone of three groups of horses: (1) young racing Thoroughbreds (n = 10); (2) young unshod ponies (n = 10); and (3) older horses with navicular syndrome (n = 6). Navicular syndrome is a painful condition that is a common cause of lameness and is associated with extensive remodeling of the navicular bone; a sesamoid bone located within the hoof which articulates with the second and third phalanges dorsally. The following variables were quantified: volumetric bone mineral density; cortical thickness (Ct.Th); bone volume fraction, microcrack surface density; density of osteocytes and empty lacunae; and resorption space density. Birefringence of bone collagen was also determined using circularly polarized light microscopy and disruption of the lacunocanalicular network was examined using confocal microscopy. Remodeling of the navicular bone resulted in formation of transverse secondary osteons orientated in a lateral to medial direction; bone collagen was similarly orientated. In horses with navicular syndrome, remodeling often led to the formation of intracortical cysts and development of multiple tidemarks at the articular surface. These changes were associated with high microcrack surface density, low bone volume fraction, low density of osteocytes, and poor osteocyte connectivity. Empty lacunae were increased in Thoroughbreds. Resorption space density was not increased in horses with navicular syndrome. Taken together, these data suggest that the navicular bone may experience habitual bending across the sagittal plane. Consequences of cumulative cyclic loading in horses with navicular syndrome include arthritic degeneration of adjacent joints and adaptive failure of the navicular bone, with accumulation of microdamage and associated low bone mass, poor osteocyte connectivity, and low osteocyte density, but not formation of greater numbers of resorption spaces.
Age estimation in the Mediterranean bottlenose dolphinTursiops truncatus(Montagu 1821) by bone density of the thoracic limb
Authors: Butti Camilla , Corain Livio , Cozzi Bruno , Podestà Michela , Pirone Andrea , Affronte Marco , Zotti Alessandro
Published: October 2007

The determination of age is an important step in defining the life history traits of individuals and populations. Age determination of odontocetes is mainly based on counting annual growth layer groups in the teeth. However, this useful method is always invasive, requiring the cutting of at least one tooth, and sometimes the results are difficult to interpret. Based on the concept that bone matrix is constantly deposited throughout life, we analysed the bone mineral density of the arm and forearm of a series of bottlenose dolphins (Tursiops truncatus, Montagu 1821) stranded along the Italian coast of the Adriatic Sea or maintained in confined waters. The bone mineral density values we obtained were evaluated as possible age predictors of the Mediterranean population of this species, considering age as determined by counting growth layer groups in sections of the teeth and the total body length of the animal as references. Comparisons between left and right flipper showed no difference. Our results show that bone mineral density values of the thoracic limb are indeed reliable age predictors inTursiops truncatus. Further investigations in additional odontocete species are necessary to provide strong evidence of the reliability of bone mineral density as an indicator of growth and chronological wear and tear in toothed‐whales.
Initial motor axon outgrowth from the developing central nervous system
Authors: Fraher J. P. , Dockery P. , O'Donoghue O. , Riedewald B. , O’Leary D.
Published: October 2007

Rat and chick studies show that the earliest motor rootlet axon bundles emerge from all levels of the neural tube between radial glial end feet which comprise the presumptive glia limitans. The loose arrangement of the end feet at the time of emergence facilitates this passage. The points of emergence are regularly spaced in relation to the long axis of the neural tube and are not defined by any cell contact with its surface. Each rootlet carries a covering of basal lamina from the neural tube surface, which forms a sleeve around it. It is only after bundles of ventral rootlet axons have emerged that cells associate with them, forming clusters on the rootlet surface at a distance peripheral to the CNS surface of both species. A tight collar of glial end feet develops around the axon bundle at the neural tube surface shortly after initial emergence. These arrangements are in sharp contrast to those seen in the sensory rootlets, where clusters of boundary cap cells prefigure the sensory entry zones at the attachments of the prospective dorsal spinal and cranial sensory rootlets. Boundary cap cells resemble cluster cells and a neural crest origin seems the most likely for them. The study clearly demonstrates that no features resembling boundary caps are found in relation to the developing motor exit points.
Immunohistochemical analysis of Sonic hedgehog signalling in normal human urinary tract development
Authors: Jenkins Dagan , Winyard Paul J. D. , Woolf Adrian S.
Published: October 2007

Studies of mouse mutants have demonstrated that Sonic hedgehog (SHH) signalling has a functional role in morphogenesis and differentiation at multiple sites within the forming urinary tract, and urinary tract malformations have been reported in humans with mutations that disrupt SHH signalling. However, there is only strikingly sparse and fragmentary information about the expression of SHH and associated signalling genes in normal human urinary tract development. We used immunohistochemistry to demonstrate that SHH protein was localised in distinct urinary tract epithelia in developing normal humans, in the urothelium of the nascent bladder and in kidney medullary collecting ducts. The expression patterns of the SHH‐transducing proteins Patched (PTCH) and Smoothened (SMO) were consistent with long‐range paracrine signalling associated with detrusor smooth muscle differentiation in the urogenital sinus. In the developing kidney, SHH and PTCH were expressed in epithelia of the collecting system between 16–26 weeks – surprisingly, SMO was not detected. Analysis of cell proliferation and Cyclin B1 immunohistochemistry at 26 weeks, as compared with a 28 week sample in which SHH expression was down‐regulated, was consistent with the idea that SHH and PTCH might influence medullary collecting duct growth by regulating the subcellular localisation of Cyclin B1 independently of SMO. Collectively, these descriptive results generate new hypotheses regarding SHH signal transduction in human urinary tract development and help to explain the varied urinary tract malformation phenotypes noted in individuals with mutations in the SHH pathway.
Fine root heterogeneity by branch order: exploring the discrepancy in root turnover estimates between minirhizotron and carbon isotopic methods
Authors: Guo Dali , Li Harbin , Mitchell Robert J. , Han Wenxuan , Hendricks Joseph J. , Fahey Timothy J. , Hendrick Ronald L.
Published: October 2007

DOI:10.1111/j.1469-8137.2007.02335.x
Influence of gelatin and starch on the instrumental and sensory texture of stirred yogurt
Authors: ARES GASTÓN , GONÇALVEZ DENISSE , PÉREZ CECILIA , REOLÓN GABRIELA , SEGURA NADIA , LEMA PATRICIA , GÁMBARO ADRIANA
Published: October 2007

The effect of the addition of gelatin and starch on the rheological and sensory texture properties of sweetened plain stirred yogurt was studied. Six samples were prepared: two with gelatin (3 and 6 mg/g), three with starch (1, 5 and 10 mg/g) and a control sample without thickener. Rheological measurements were performed and flow curves were modelled according to the Herschel–Bulkley rheological model. Also, sensory evaluation was carried out using a trained panel. The addition of gelatin and starch significantly affected the instrumental texture parameters (Herschel–Bulkley's model parameters and syneresis) and the perceived sensory texture of yogurts. All sensory descriptors were well predicted by the partial least squares regression of the instrumental parameters. The addition of thickeners significantly reduced syneresis. Samples produced with 6 mg/g of gelatin did not show syneresis and showed the highest sensory viscosity, creaminess and mouth‐feel. Therefore, the use of 6 mg/g of gelatin could be a reasonable concentration to use in the production of low‐fat yogurts.
Using near infrared spectroscopy for the determination of total solids and protein content in cheese curd
Authors: SULTANEH ALI , ROHM HARALD
Published: October 2007

In‐line or on‐line monitoring requires fast and reliable methods for determining composition or processing variables. A near infrared spectroscopic method for the determination of solids and protein content in cheese curd has been developed. Based on approximately 250 curd samples, calibration models were built using partial least squares regression. The calibration models resulted in coefficients of determination of R2 = 0.994 for total solids and R2 = 0.985 for protein content for unhomogenized curd, which improved only slightly after subjecting the curd to homogenization. As confirmed by results that were obtained from a validation set, this suggests that near infrared spectroscopy is a potential and powerful method for the rapid monitoring of curd composition.
Functional properties of native and cheese whey protein concentrate powders
Authors: HEINO ANTTI T , UUSI‐RAUVA JANNE O , RANTAMÄKI PIRJO R , TOSSAVAINEN OLLI
Published: October 2007

The objective of this study was to compare microfiltered native whey protein concentrate and traditional cheese whey protein concentrate powders and their functional properties. Solubility, viscosity, gelation, foaming properties, emulsification and water‐holding capacity were studied. The effect of spray and freeze drying methods on functional properties was evaluated. Gel strength varied from 0.11 to 0.65 N. Foaming stability and overrun varied from 0 to 29.3 min and from 230 to 2200%, respectively. Foaming and gelation properties were clearly better with native whey protein powders. Differences between drying methods were not observed but higher heat load decreased solubility.
Evaluation of de‐lipidated egg yolk and yeast autolysate as growth supplements for lactic acid bacteria culture
Authors: DJEGHRI‐HOCINE BAIDA , BOUKHEMIS MESSAOUDA , ZIDOUNE MOHAMMED NASREDDINE , AMRANE ABDELTIF
Published: October 2007

Four strains of lactic acid bacteria (LAB) were cultivated on deproteinated whey supplemented with yeast autolysate (YA) and/or de‐lipidated egg yolk (DEY). Growth was compared to that recorded on the widely used MRS medium. The feasibility of the use of YA in place of yeast extract was confirmed. In the presence of YA in the medium, cell numeration gained nearly 1 log for only 0.4% DEY added in the culture medium, namely 0.1 g/L additional nitrogen, showing that DEY also supplies LAB growth in trace elements and growth factors like vitamins. If compared to the MRS medium, final cell numerations were about 1 log lower on deproteinated whey supplemented with YA and DEY, while the protein nitrogen ratio of both media was 2.7, showing the high potential of the tested supplements, and especially DEY. Subsequent works with higher and hydrolysed DEY may be therefore useful.
REST is a key regulator in brain‐specific homeobox gene expression during neuronal differentiation
Authors: Park So Yun , Kim Jae Bum , Han Yong‐Mahn
Published: October 2007

Brain‐specific homeobox (Bsx) is specifically expressed at the early embryonic stages during brain development. Several studies show that Bsx plays important roles in brain development; however, the mechanisms of its transcriptional regulation remain to be established. In this study, we show that binding of repressor element silencing transcription factor (REST) to the neuron restrictive silencer element (NRSE) represses Bsx transcription in non‐neuronal P19 cells. The Bsx promoter contains several putative binding sites for transcription factors, including NRSE for REST and the GC box for the transcriptional activator, Sp1. Upon neuronal differentiation of P19 cells with retinoic acid, Bsx gene expression increased, whereas that of the REST gene decreased. Electrophoretic mobility shift analyses demonstrated that recombinant REST proteins bound the NRSE region of the Bsx promoter. In neuronal NS20Y cells, transcriptional activity of the Bsx promoter was decreased upon expression of REST. Moreover, dominant‐negative REST derepressed Bsx transcription in P19 cells. Sp1‐mediated transcriptional activity of the Bsx promoter was attenuated by treatment with mithramycin A, a GC box‐binding drug, but was enhanced upon mutation of NRSE. Co‐immunoprecipitation and chromatin immunoprecipitation assays showed that the Bsx promoter appeared to be modulated by direct interactions between REST and Sp1. The CpG sites of NRSE and GC box were completely unmethylated, signifying no interference of DNA methylation. Our results suggest that binding of REST to NRSE suppresses the Sp1‐mediated activation of Bsx in non‐neuronal cells.
Neural precursors derived from human embryonic stem cells maintain long‐term proliferation without losing the potential to differentiate into all three neural lineages, including dopaminergic neurons
Authors: Hong Sunghoi , Kang Un Jung , Isacson Ole , Kim Kwang‐Soo
Published: October 2007

Human embryonic stem (hES) cells have the ability to renew themselves and differentiate into multiple cell types upon exposure to appropriate signals. In particular, the ability of hES cells to differentiate into defined neural lineages, such as neurons, astrocytes, and oligodendrocytes, is fundamental to developing cell‐based therapies for neurodegenerative disorders and studying developmental mechanisms. However, the utilization of hES cells for basic and applied research is hampered by the lack of well‐defined methods to maintain their self‐renewal and direct their differentiation. Recently we reported that neural precursor (NP) cells derived from mouse ES cells maintained their potential to differentiate into dopaminergic (DA) neurons after significant expansion in vitro. We hypothesized that NP cells derived from hES cells (hES‐NP) could also undergo the same in vitro expansion and differentiation. To test this hypothesis, we passaged hES‐NP cells and analyzed their proliferative and developmental properties. We found that hES‐NP cells can proliferate approximately 380 000‐fold after in vitro expansion for 12 weeks and maintain their potential to generate Tuj1+ neurons, GFAP+ astrocytes, and O4+ oligodendrocytes as well as tyrosine hydroxylase‐positive (TH+) DA neurons. Furthermore, TH+ neurons originating from hES‐NP cells expressed other midbrain DA markers, including Nurr1, Pitx3, Engrail‐1, and aromatic l‐amino acid decarboxylase, and released significant amounts of DA. In addition, hES‐NP cells maintained their developmental potential through long‐term storage (over 2 years) in liquid nitrogen and multiple freeze–thaw cycles. These results demonstrate that hES‐NP cells have the ability to provide an expandable and unlimited human cell source that can develop into specific neuronal and glial subtypes.
Role of KATP channels in protection against neuronal excitatory insults
Authors: Soundarapandian Mangala M. , Zhong Xiaofen , Peng Lisheng , Wu Di , Lu Youming
Published: October 2007

ATP‐sensitive K+ (KATP) channels that are gated by intracellular ATP/ADP concentrations are a unique subtype of potassium channels and play an essential role in coupling intracellular metabolic events to electrical activity. Opening of KATP channels during energy deficits in the CNS induces efflux of potassium ions and in turn hyperpolarizes neurons. Thus, activation of KATP channels is thought to be able to counteract excitatory insults and protect against neuronal death. In this review, we bring together recent studies about what kinds of molecules are needed to build and regulate arrays of KATP channel functions in the CNS neurons. We propose a model to explain how KATP channel activation regulates glutamate release from the pre‐synaptic terminals and how this regulation protects against ischemic neuronal injury and epilepsy.
Intracellular accumulation of a mild‐denatured monomer of the human PrP fragment 90–231, as possible mechanism of its neurotoxic effects
Authors: Chiovitti Katia , Corsaro Alessandro , Thellung Stefano , Villa Valentina , Paludi Domenico , D’Arrigo Cristina , Russo Claudio , Perico Angelo , Ianieri Adriana , Di Cola Domenico , Vergara Alberto , Aceto Antonio , Florio Tullio
Published: October 2007

Because of high tendency of the prion protein (PrP) to aggregate, the exact PrP isoform responsible for prion diseases as well as the pathological mechanism that it activates remains still controversial. In this study, we show that a pre‐fibrillar, monomeric or small oligomeric conformation of the human PrP fragment 90–231 (hPrP90–231), rather than soluble or fibrillar large aggregates, represents the neurotoxic species. In particular, we demonstrate that monomeric mild‐denatured hPrP90–231 (incubated for 1 h at 53°C) induces SH‐SY5Y neuroblastoma cell death, while, when structured in large aggregates, it is ineffective. Using spectroscopic and cellular techniques we demonstrate that this toxic conformer is characterized by a high exposure of hydrophobic regions that favors the intracellular accumulation of the protein. Inside the cells hPrP90–231 is mainly compartmentalized into the lysosomes where it may trigger pro‐apoptotic ‘cell death’ signals. The PrP toxic conformation, which we have obtained inducing a controlled in vitro conformational change of the protein, might mimic mild‐unfolding events occurring in vivo, in the presence of specific mutations, oxidative reactions or proteolysis. Thus, in light of this model, we propose that novel therapeutic strategies, designed to inhibit the interaction of the toxic PrP with the plasmamembrane, could be beneficial to prevent the formation of intracellular neurotoxic aggregates and ultimately the neuronal death.
Mechanisms of [3H]glycine release from mouse spinal cord synaptosomes selectively labeled through GLYT2 transporters
Authors: Luccini Elisa , Raiteri Luca
Published: October 2007

Glycine release has been rarely studied. The aim of this work was to characterize the release of the amino acid from spinal cord glycinergic nerve endings selectively pre‐labeled through glycine transporters of the GLYT2 type. Purified mouse spinal cord synaptosomes were incubated with [3H]glycine in the presence of the GLYT1 blocker N‐[(3R)‐3‐([1,1′‐biphenyl]‐4‐yloxy)‐3‐(4‐fluorophenyl)propyl]‐N‐methylglycine hydrochloride and exposed in superfusion to varying concentrations of KCl, 4‐aminopyridine (4‐AP), or veratridine. KCl (≤ 15 mmol/L), 4‐AP (up to 1 mmol/L), and veratridine (≤ 0.3 μmol/L)‐provoked [3H]glycine release by external Ca2+‐dependent, botulinum toxin C1‐sensitive, exocytosis. The overflows evoked by higher concentrations of K+ or veratridine involved external Ca2+‐independent mechanisms of different nature. Only the overflow evoked by 3 or 10 μmol/L veratridine occurred totally (3 μmol/L) or in part (10 μmol/L) by transporter reversal, being sensitive to the GLYT2 blockers 4‐benzyloxy‐3,5‐dimethoxy‐N‐[1‐(dimethylaminociclopentyl)‐methyl] benzamide or O‐[(2‐benzyloxyphenyl‐3‐flurophenyl)methyl]‐l‐serine; in contrast, the external Ca2+‐independent [3H]glycine overflow provoked by 50 mmol/L K+ was transporter‐independent. This component of K+‐evoked overflow and the GLYT2‐independent portion of the 10 μmol/L veratridine‐evoked overflow, were largely sensitive to the vesicle depletor bafilomycin or BAPTA‐AM and were prevented by blocking the mitochondrial Na+/Ca2+ exchanger with 7‐chloro‐5‐(2‐chlorophenyl)‐1,5‐dihydro‐4,1‐benzothiazepin‐2(3H)‐one, indicating the involvement of exocytosis triggered by intraterminal mitochondrial Ca2+ ions.
Alterations of cerebral cortex and hippocampal proteasome subunit expression and function in a traumatic brain injury rat model
Authors: Yao Xianglan , Liu Jiong , McCabe Joseph T.
Published: October 2007

Following cellular stress or tissue injury, the proteasome plays a critical role in protein degradation and signal transduction. The present study examined the β‐subunit expression of constitutive proteasomes (β1, β2, and β5), immunoproteasomes (β1i, β2i, and β5i) and the 11S proteasome activator, PA28α, in the rat CNS after traumatic brain injury (TBI). Concomitant measures assessed changes in proteasome activities. Quantitative real time PCR results indicated that β1 and β2 mRNA levels were not changed, while β5 mRNA levels were significantly decreased in injured CNS following TBI. However, β1i, β2i, β5i, and PA28α mRNA levels were significantly increased in the injured CNS. Western blotting studies found that β1, β2, β5, β2i, and β5i subunit protein levels remained unchanged in the injured CNS, but β1i and PA28α protein levels were significantly elevated in ipsilateral cerebral cortex and hippocampus. Proteasome activity assays found that peptidyl glutamyl peptide hydrolase‐like and chymotrypsin‐like activity were significantly reduced in the CNS after TBI, and that trypsin‐like proteasome activity was increased in the injured cerebral cortex. Our results demonstrated that both proteasome composition and function in the CNS were affected by trauma. Treatments that preserve proteasome function following CNS injury may be beneficial as an approach to cerebral neuroprotection.
Differential distribution of proteins and lipids in detergent‐resistant and detergent‐soluble domains in rod outer segment plasma membranes and disks
Authors: Elliott Michael H. , Nash Zack A. , Takemori Nobuaki , Fliesler Steven J. , McClellan Mark E. , Naash Muna I.
Published: October 2007

Membrane heterogeneity plays a significant role in regulating signal transduction and other cellular activities. We examined the protein and lipid components associated with the detergent‐resistant membrane (DRM) fractions from retinal rod outer segment (ROS) disk and plasma membrane‐enriched preparations. Proteomics and correlative western blot analysis revealed the presence of α and β subunits of the rod cGMP‐gated ion channel and glucose transporter type 1, among other proteins. The glucose transporter was present exclusively in ROS plasma membrane (not disks) and was highly enriched in DRMs, as was the cGMP‐gated channel β‐subunit. In contrast, the majority of rod opsin and ATP‐binding cassette transporter A4 was localized to detergent‐soluble domains in disks. As expected, the cholesterol : fatty acid mole ratio was higher in DRMs than in the corresponding parent membranes (disk and plasma membranes, respectively) and was also higher in disks compared to plasma membranes. Furthermore, the ratio of saturated : polyunsaturated fatty acids was also higher in DRMs compared to their respective parent membranes (disk and plasma membranes). These results confirm that DRMs prepared from both disks and plasma membranes are enriched in cholesterol and in saturated fatty acids compared to their parent membranes. The dominant fatty acids in DRMs were 16 : 0 and 18 : 0; 22 : 6n3 and 18 : 1 levels were threefold higher and twofold lower, respectively, in disk‐derived DRMs compared to plasma membrane‐derived DRMs. We estimate, based on fatty acid recovery that DRMs account for only ∼ 8% of disks and ∼ 12% of ROS plasma membrane.
Polymorphic microsatellite markers for the lizard Psammodromus algirus (Squamata: Lacertidae)
Authors: BLOOR P. , DÁVILA J. A.
Published: October 2007

Eight microsatellite loci are described for the lizard Psammodromus algirus, a species widely used as a model in behavioural and ecological studies. All loci were highly polymorphic (six alleles or more per locus) in a sample of 24 individuals from a single site near Navacerrada (central Spain). Observed heterozygosity ranged from 0.29 to 0.96. These markers will be used to study mating strategies and determinants of reproductive success in this species.
ARBITRATION IN PERSPECTIVE—A FURTHER COMMENT
Authors: Oxnam D.W.
Published: October 2007

To sum up: (1) The contribution of arbitration to the settlement of strikes varies very considerably as between different industries. In industry as a whole, the contribution of arbitration has risen very appreciably since the war but it would appear that this is due more to changes in the industrial composition of aggregate strike data rather than to a substitution of arbitration for other methods in particular industries. A more detailed industry split‐up of the data over a longer period of years would be required in order to reach any firm conclusions on this point. If account be taken of the disputes settled by the industrial tribunals before culminating in strike action, then the contribution of this institution towards industrial peace would be even more significant than indicated by the preceding analysis. (2) Apart from any influence which it may have had upon the course of the general level of real wages over the past half century, there can be no doubt that compulsory arbitration, as it has operated in this country, has been a powerful factor in bringing about a greater degree of relative wage justice in the sense that it has facilitated the application of the “rate for the job” principle on a national basis. This has been particularly beneficial to the weakly organized groups including the white collar workers. (3) Australian trade unionism owes much to the arbitration system in terms of its enhanced membership and extensive interstate and national coverage. (4) As against these substantial gains it must be recognized that under existing arbitration law, Australian trade unions are less free than are those in either the United Kingdom or the United States or indeed in any other democratic country except New Zealand.
IMPERIAL PREFERENCE:THE CASE OF AUSTRALIAN BEEF IN THE 1930s
Authors: Duncan R.
Published: October 2007

During the 1930s, the Australian beef export industry, after protracted negotiations, was granted substantial concessions by the British Government. This paper traces the development of British and Australian government policies during the decade, shows how considerably the Australian beef industry benefited from concessions made to it at Ottawa in 1932 and, more particularly, in subsequent years, and concludes with a discussion of the considerations which appear to have influenced British decisions
The Tax Cut as an Anti‐Inflationary Measure*
Authors: Brennan G. , Auld D. A. L.
Published: October 2007

‘…the Government is convinced that the right course at this juncture, and the best contribution it can make to the solution of the current problems of our economy, is a bold policy of reducing taxes—particularly those taxes which are levied directly upon individuals and upon business. We believe that this is the best form of assistance we can give in the attack on costs. Essentially, the cost problem is one to be solved by greater efforts and greater efficiency on the part of both labour and management. By reducing taxes and so making wages and profits more worth earning, the Government can provide an inducement to greater effort and greater efficiency…’

‘…the Government proposes to reduce taxes up to the limit of budget capacity after making provision for essential expenditures… and it has devised the tax reductions in a way that will ensure the maximum incentive to effort while making whenever possible a direct reduction in costs. At the same time it has taken care to ensure that the Budget for the year will balance; for there could be no thought at a time like this of adding to the volume of spending power by the process of deficit‐financing… As in last year's Budget, the greatest weight should be given to reductions of Income Tax on individuals. By so doing the benefits will spread most widely and the greatest number of people will receive a further incentive to work and to save. The Government has, however, explored the possibilities of reducing indirect taxation, and it is proposing some very useful reductions in that field. Some of these reductions will make an important direct contribution to the problem of reducing costs’
Wage Inertia and Comparison Effects in Australian Award Wage Determination, 1964‐74*
Authors: TRIVEDI P. K. , RAYNER J.
Published: October 2007

This paper attempts to explain the determination of average award wage changes without assuming that the outcome of certain strategic wage settlements is known. Models which allow for habit‐inertia and comparison effects are constructed. It is argued that the main impact of these factors is on the specification and interpretation of lagged adjustment of wages to changes in its determinants. These models are empirically tested using the pre‐indexation quarterly data. An analysis of 1973‐74 wage experience is also provided.
Short Term Econometric Forecasting and Seasonal Adjustment
Authors: BABICH GEORGE , GOODHEW JOHN
Published: October 2007

Seasonal behaviour in the variables of an econometric model is usually handled in one of two ways—either the data are adjusted prior to estimation, or seasonal binary variables are included in the specification and estimation of the model. Although the literature on the subject is extensive, it is not obvious which of these procedures is best for forecasting. This paper compares the forecasting ability of a small model of the Australian economy for each of the alternative approaches to seasonal adjustment.
A Model of Resource Depletion with Multiple Grades*
Authors: ULPH ALISTAIR M.
Published: October 2007

The standard extension of the Hotelling model of resource depletion to consider multiple grades leads to sequential development of successively poorer grades. However, this is not what is observed, and this paper formalises one reason for simultaneous exploitation—the existence of overhead costs in the preparation of a mine. It is shown that the structure of rents which is obtained in the simple model of multiple grades still applies in this more complex situation.
Devaluation, Inflation, and the Balance of Payments: A Short‐Run Monetary Approach*
Authors: BLEJER MARIO I.
Published: October 2007

In this paper a model is presented to analyze, in a monetary setting, the effects of a once‐and‐for‐all adjustment in the exchange rate in a small economy committed to a fixed exchange‐rate system. The effects of such an adjustment are shown to be transitory. After a devaluation the domestic rate of inflation accelerates in relation to the rate of inflation in the rest of the world. The increase in prices reduces the real value of the nominal stock of money and, in order to restore real liquidity to its previous level, foreign‐exchange reserves start to flow into the country. However, as monetary equlibrium is reached, the flow of reserves tends to stop and the domestic rate of inflation converges to the world rate.
Some Implications of Uncertainty in a Small Open Economy
Authors: KEMP MURRAY C. , OHTA HIROSHI
Published: October 2007

Consider a small open economy which produces two commodities, the first a consumers' good and the second a producers' good, by means of a conventional no‐joint‐products technology. Suppose that one of the two production functions is subject to a random multiplicative disturbance and that factors of production must be allocated to the two industries before the realization of the random variable. It is known that if in the absence of uncertainty production is incompletely specialized then the same is true under uncertainty although the average output of the uncertain industry is lower. In the present paper we suppose that each of the two production functions is subject to a random multiplicative disturbance but restrict our attention to three particular cases: the polar cases of perfect correlation, positive and negative, and the intermediate case of zero correlation. It is shown that in none of these cases does there exist an obvious and complete analogue of the above proposition but that in each case something definite can be said, either about the possibility of complete specialization under uncertainty or about the effect of uncertainty on the allocation of factors (but not about both).
Environmental Pollution in an Open Economy*
Authors: ASAKO KAZUMI
Published: October 2007

This paper attempts to analyze an interaction between international trade and domestic environmental pollution. A country engaging in international trade biases its domestic economic structure toward exportable sectors. The bias thus caused has a significant impact on the quality of the environment. It will be shown that a country can and should control international trade activities as a means of dealing with pollution problems. One of the paper's main purposes is to give a warning to a country which expands its international trade activities without taking serious consideration of its domestic environment.
Excess Demand and ExDectations Influences on Price Changes in Australian Manufacturing Industry*
Authors: HALL V. B.
Published: October 2007

Data from the quarterly ‘Survey of Industrial Trends in Australia’ have been used to evaluate whether various excess demad and expectations influences have significantly effected reported price changes in Australian manufacturing industry. For the manufacturing sector, as a whole. both expected and unexpected changes in average unit costs have been important, but no explicit excess demand influence has been additionally significant at the I per cent level. For a majority of the indrutry categories tested, however, certain excess dgmand variables (involving. for example, finished goods inventories, unfilled orders. and industry operating rates) and various cost and inventory expectations variables have been significant.
Politico‐Economic Interactions in Australia:Some Empirical Evidence*
Authors: SCHNEIDER FRIEDRICH , POMMEREHNE WERNER W.
Published: October 2007

A politico‐economic model for the Australian government is developed. based on some simple theoretical hypotheses concerning the interrelationship between the economy and polity. The popularity function describes the first link between the state of the economy and the voters' behaviour. It is shown that under correct specification, which includes both economic and political factors, unemployment and infldtion have a sizeable quantitative influence on government popularity. The second major link is described by the policy function. There it is shown that due to the short legislative period, the Australian government's efforts are permanently directed to securing re‐election as its most major goal.
Monetary and Fiscal Policy in a Long‐Run Macroeconomic Model*
Authors: TURNOVSKY STEPHEN J.
Published: October 2007

This paper develops a macroeconomic model in which the conventional short‐run system is embedded in a long‐run model, incorporating the dymics of asset accumulation and other longer‐run dynamic adjustments. Most attention is devoted to analyzing the steady state under alternative assumptions regarding government financial policies. It shows how, with full employment ultimately attained, the equilibrium levels of capital, real money balances. real stock of bonds. and the long‐run rate of inflation are simultaneously determined. The effects of an expansion in government expenditure under bond financing and money financing are compared in detail.
Location and Pollution in a Communal Society
Authors: STANLEY OWEN
Published: October 2007

The model presented in this paper attempts to explain the recent trend among Australian Aboriginals in remote Australia to abandon large settlements in favour of much smaller decentralized settlements. The model does, however, have implications for modern Western societies. Aboriginals are assumed to like money and non‐money income, stability of income, nearness to a place of significance and a low degree of private property rights, and to dislike pollution when interpreted broadly. Each of these determinants of werfare is expressed as a function of location and degree of private property rights alone and a utility function is maximized with respect to these two variables. The impact on the optimal location and property rights decision of a number of recent changes is then considered.
Some Economic ImDlications of Technical Change in Australia to 1990–91:An Illustrative Application of the SNAPSHOT Model*
Authors: DIXON P. B. , VINCENT D. P.
Published: October 2007

SNAPSHOT is a programming model (of the type often found in the Development literature) of the Australian economy. This paper contains (i) a brief critical overview of the SNAPSHOT theory and (ii) an illustrative application. Forecasts, derived from work by the Bureau of Industry Economics and the IMPACT project. of industry technology in 1990 are wed as an input to SNAPSHOT. The model results then provide a bash for discussing some of the implications of ‐technical change for industry growth prospects and employment prospects by occupation.
A Comparison of Purchasing Power Parity between the Pound Sterling and the Australian Dollar in 1979*
Authors: SHEPHERD W. F. , RAO D. S. PRASADA
Published: October 2007

This paper attempts to compare the cost of living in Australia and the United Kingdom. The comparisons are made on the basis of price and expenditure shares information provided predominantly by the Australian Bureau of Statistics and the Department of Employment, London, and from a private survey conducted by one of the authors in London and Sydney in December 1979. Due to the nature of the data, absence of quantity information, it was necessary to employ a new index number method derived by one of the authors.
A Social Safety Net for the Impact of Technical Change:An Evaluation of the Myers Committee's Adjustment Assistance Proposal*
Authors: CASSING J. H. , HILLMAN A. L.
Published: October 2007

This paper assesses the ‘social safety net’ proposal of the Myers Committee Report on Technological Change as a programme aimed to ameliorate the losses of individuals adversely affected by technical progress. The point is made that, while the safety net is geared toward retrenched employees moving through the unemployment pool, much of the actual loss from unanticipated technical progress is taken as writ ten‐down capital values by immobile factor owners tied to the old technology. In the end, the safely net amounts to little more than increased unemployment benefits which do not compensate many of the injured parties. Moreover, by deviating from the standard unemployment benefits scheme in having their supplementary scheme internalize some of the costs of such benefits within the firm, the Myers Committee proposal thus hinders the very adjustment to technological change which one might have supposed the scheme would seek to facilitate.
Inflation in the USA, UK and Australia:Some Comparisons*
Authors: PERRY L. J.
Published: October 2007

USA, UK and Australian wage inflation experiences during the post‐World‐War‐II period are examined principally within the framework of the long‐run Phillips curve model. Attention is drawn to the sensitivity of wage rate changes to retail price level changes and to the possibility of a temporal change in this relationship. The analyses of these countries are compared so as to highlight similarities and differences.
The Good Fight*
Authors: HOLMES A. S.
Published: October 2007

This paper is concerned with aspects of policy‐making which tend to impede economic efficiency, and with steps which might enhance such efficiency. Various problems and impediments are discussed first. The paper then looks at the roles of advisers and ministers. It concludes with a somewhat speculative look at ways in which opinion, advice and policies might change.
Determinants of Female Employment*
Authors: EYLAND E. A. , MASON C. A. , LAPSLEY H. M.
Published: October 2007

A survey of 1030 women aged between 20 and 60 years was made in 1977 in Eastwood, a middle‐class suburb of Sydney. It was used to measure the size of the female labour force and the level of unemployment in the area. In addition, logit analysis was applied to the data to identify the personal and family characteristics that determined work behaviour. It was found that active workforce participation and hours of work could be explained adequately by only four variables—age of respondent, marital status, education level and (where relevant) age of youngest child.
Factor Substitutability in Australian Manufacturing with Emphasis on Energy Inputs*
Authors: TURNOVSK MICHELLE , FOLIE MICHAEL , ULPH ALISTAIR
Published: October 2007

In this paper a model of the production structure in the aggregate Australian manufacturing sector is estimated, emphasizing the use this sector makes of energy inputs. A translog cost function is estimated with time‐series data for four inputs, capital services, labour services, energy and materials and likewise an energy submodel is estimated for solid fuels, oil, electricity and gas. The substitutabilily and the complementarity relationships between the various factor inputs and between the various fuels are examined: an interesting finding is that capital and energy are substitutes and labour and energy are complements. Factor price elasticities are calculated and turn out to be quite significant. The study concludes that rising energy prices will induce significant shifts in both the mix of fuel inputs and the level of aggregate energy utilization.