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Cycle
Kinds of Cycle Terms modified by Cycle Selected AbstractsSTOCK RETURNS, ASYMMETRIC VOLATILITY, RISK AVERSION, AND BUSINESS CYCLE: SOME NEW EVIDENCEECONOMIC INQUIRY, Issue 2 2008SEI-WAN KIM We study how three interrelated phenomena,excess stock returns and risk relation, risk aversion, and asymmetric volatility movement,change over business cycles. Using an asymmetric generalized autoregressive conditional heteroskedasticity in mean model and a Markov switching model, we find that excess stock return increases and asymmetric volatility movement is weakened during boom periods. This suggests that investors become more risk-averse during boom periods (i.e., procyclical risk aversion), which we confirm using a calibration of a simple equilibrium model. (JEL C32, E32, G12) [source] FISCAL DECENTRALIZATION AND THE BUSINESS CYCLE: AN EMPIRICAL STUDY OF SEVEN FEDERATIONSECONOMICS & POLITICS, Issue 1 2010JONATHAN RODDEN Although fiscal policies of central governments sometimes provide modest insurance against regional income shocks, this paper shows that procyclical fiscal policy among provincial governments can easily overwhelm these stabilizing effects. We examine the cyclicality of budget items among provincial governments in seven federations, showing that own-source taxes are generally highly procyclical, and contrary to common wisdom, revenue sharing and discretionary transfers are either acyclical or procyclical. Constituent governments are thus left alone to smooth their own shocks, and we document the extent to which various restraints on borrowing and saving undermine their ability to do so. The resulting procyclicality of provincial fiscal policy is likely to have important implications in a world where demands for countercyclical fiscal policy are increasing but considerable fiscal responsibilities are being devolved to subnational governments. [source] HOUSING AND THE BUSINESS CYCLE*INTERNATIONAL ECONOMIC REVIEW, Issue 3 2005Morris A. Davis In the United States, the percentage standard deviation of residential investment is more than twice that of nonresidential investment. In addition, GDP, consumption, and both types of investment co-move positively. We reproduce these facts in a calibrated multisector growth model where construction, manufacturing, and services are combined, in different proportions, to produce consumption, business investment, and residential structures. New housing requires land in addition to new structures. The model can also account for important features of industry-level data. In particular, hours and output in all industries are positively correlated, and are most volatile in construction. [source] A COMPREHENSIVE STUDY OF THE LIFE CYCLE OF A SOUTH AMERICAN POPULATION OF STIGEOCLONIUM TENUE (CHAETOPHORALES, CHLOROPHYTA),JOURNAL OF PHYCOLOGY, Issue 5 2010Karina M. Michetti The diplobiontic,haplodiplontic life cycle with alternating isomorphic generations in Stigeoclonium tenue (C. Agardh) Kütz. is described for the first time. Sporophytes (2n = 10) arise from tetraflagellate zoospores that are produced by meiosis. Sporic meiosis might be inferred from the cruciform divisions formed during zoosporogenesis and is confirmed through observations of prophase I substages. Zoospores do not germinate directly but produce a haploid cyst that germinates to give rise to a gametophyte (n = 5). Gametophytes produce biflagellate isogametes, which fuse to produce zygotes that germinate by mitosis into the sporophytic stage. Gametophytes and sporophytes reproduce asexually both via mitotic tetraflagellate zoospores and by thallus fragmentation. Results from this study indicate that both the cosmopolitan distribution and dominance of S. tenue in many periphytic communities might be due to its multiple reproductive strategies. [source] A NEW CELL STAGE IN THE HAPLOID-DIPLOID LIFE CYCLE OF THE COLONY-FORMING HAPTOPHYTE PHAEOCYSTIS ANTARCTICA AND ITS ECOLOGICAL IMPLICATIONS,JOURNAL OF PHYCOLOGY, Issue 5 2010Steffi Gaebler-Schwarz Few members of the well-studied marine phytoplankton taxa have such a complex and polymorphic life cycle as the genus Phaeocystis. However, despite the ecological and biogeochemical importance of Phaeocystis blooms, the life cycle of the major bloom-forming species of this genus remains illusive and poorly resolved. At least six different life stages and up to 15 different functional components of the life cycle have been proposed. Our culture and field observations indicate that there is a previously unrecognized stage in the life cycle of P. antarctica G. Karst. This stage comprises nonmotile cells that range in size from ,4.2 to 9.8 ,m in diameter and form aggregates in which interstitial spaces between cells are small or absent. The aggregates (hereafter called attached aggregates, AAs) adhere to available surfaces. In field samples, small AAs, surrounded by a colony skin, adopt an epiphytic lifestyle and adhere in most cases to setae or spines of diatoms. These AAs, either directly or via other life stages, produce the colonial life stage. Culture studies indicate that bloom-forming, colonial stages release flagellates (microzoospores) that fuse and form AAs, which can proliferate on the bottom of culture vessels and can eventually reform free-floating colonies. We propose that these AAs are a new stage in the life cycle of P. antarctica, which we believe to be the zygote, thus documenting sexual reproduction in this species for the first time. [source] ULTRASTRUCTURAL CHARACTERIZATION OF THE LYTIC CYCLE OF AN INTRANUCLEAR VIRUS INFECTING THE DIATOM CHAETOCEROS CF. WIGHAMII(BACILLARIOPHYCEAE) FROM CHESAPEAKE BAY, USA,JOURNAL OF PHYCOLOGY, Issue 4 2009Yoanna Eissler Numerous microalgal species are infected by viruses that have the potential to control phytoplankton dynamics by reducing host populations, preventing bloom formation, or causing the collapse of blooms. Here we describe a virus infecting the diatom Chaetoceros cf. wighamii Brightw. from the Chesapeake Bay. To characterize the morphology and lytic cycle of this virus, we conducted a time-course experiment, sampling every 4 h over 72 h following viral inoculation. In vivo fluorescence began to decline 16 h after inoculation and was reduced to <19% of control cultures by the end of experiment. TEM confirmed infection within the first 8 h of inoculation, as indicated by the presence of virus-like particles (VLP) in the nuclei. VLP were present in two different arrangements: rod-like structures that appeared in cross-section as paracrystalline arrays of hexagonal-shaped profiles measuring 12 ± 2 nm in diameter and uniformly electron-dense hexagonal-shaped particles measuring , 22,28 nm in diameter. Nuclei containing paracrystalline arrays were most prevalent early in the infection cycle, while cells containing VLP increased and then declined toward the end of the cycle. The proportion of nuclei containing both paracrystalline arrays and VLP remained relatively constant. This pattern suggests that rod-like paracrystalline arrays fragmented to produce icosahedral VLP. C. cf. wighamii nuclear inclusion virus (CwNIV) is characterized by a high burst size (averaged 26,400 viruses per infected cell) and fast generation time that could have ecological implications on C. cf. wighamii population control. [source] A UNIQUE LIFE CYCLE AND PERENNATION IN A COLORLESS CHRYSOPHYTE SPUMELLA SP.,JOURNAL OF PHYCOLOGY, Issue 1 2008Naoji Yubuki Life cycle and perennation of a colorless chrysophyte, Spumella sp., isolated from an ephemeral ditch were investigated. From a single resting cyst (statospore), only one nonmotile cell germinated. Shortly after germination, the cell generated flagella, started to swim, and formed a gelatinous sphere. The cell itself retained the ability to swim within the sphere. Cells fed on bacteria inhabiting the sphere and grew by longitudinal binary cell division very rapidly. The gelatinous sphere gradually enlarged as the number of cells increased. When it reached maximum size (,500 ,m in diameter), the gelatinous substance of the sphere weakened, and the sphere gradually broke into several pieces, forming cleavages between them. Cells swam away through the cleavages. Five to ,40 swimming cells soon gathered and formed a swarm. In the swarm, some cells cannibalized other sibling cells and enlarged, resulting in giant cells that were two to three times larger in diameter than ordinary cells. The giant cells soon started statospore formation. Statospore formation was independent of any changes of environmental factors, such as increase or decrease in temperature or changes in nutrient or light levels, which are known to induce resting-cyst formation in other groups of algae and protists. Statospore formation started when cells divided 15 to 16 times after germination. This is congruent with the idea that statospore formation in planktonic chrysophytes directly depends on cell density. An extraordinarily high growth rate and cannibalism involved in the initiation of statospore formation are interpreted as adaptations to achieve the perennation in ephemeral aquatic environments. [source] CHARACTERIZATION OF A DINOFLAGELLATE CRYPTOCHROME BLUE-LIGHT RECEPTOR WITH A POSSIBLE ROLE IN CIRCADIAN CONTROL OF THE CELL CYCLE,JOURNAL OF PHYCOLOGY, Issue 3 2007Stephanie A. Brunelle Karenia brevis (C. C. Davis) G. Hansen et Moestrup is a dinoflagellate responsible for red tides in the Gulf of Mexico. The signaling pathways regulating its cell cycle are of interest because they are the key to the formation of toxic blooms that cause mass marine animal die-offs and human illness. Karenia brevis displays phased cell division, in which cells enter S phase at precise times relative to the onset of light. Here, we demonstrate that a circadian rhythm underlies this behavior and that light quality affects the rate of cell-cycle progression: in blue light, K. brevis entered the S phase early relative to its behavior in white light of similar intensity, whereas in red light, K. brevis was not affected. A data base of 25,000 K. brevis expressed sequence tags (ESTs) revealed several sequences with similarity to cryptochrome blue-light receptors, but none related to known red-light receptors. We characterized the K. brevis cryptochrome (Kb CRY) and modeled its three-dimensional protein structure. Phylogenetic analysis of the photolyase/CRY gene family showed that Kb CRY is a member of the cryptochrome DASH (CRY DASH) clade. Western blotting with an antibody designed to bind a conserved peptide within Kb CRY identified a single band at ,55 kDa. Immunolocalization showed that Kb CRY, like CRY DASH in Arabidopsis, is localized to the chloroplast. This is the first blue-light receptor to be characterized in a dinoflagellate. As the Kb CRY appears to be the only blue-light receptor expressed, it is a likely candidate for circadian entrainment of the cell cycle. [source] MORPHOLOGICAL CHANGES IN MITOCHONDRIAL AND CHLOROPLAST NUCLEOIDS AND MITOCHONDRIA DURING THE CHLAMYDOMONAS REINHARDTII (CHLOROPHYCEAE) CELL CYCLE,JOURNAL OF PHYCOLOGY, Issue 5 2006Takayoshi Hiramatsu Morphological changes in the organellar nucleoids and mitochondria of living Chlamydomonas reinhardtii Dang were examined during the cell cycle under conditions of 12:12 light:dark. The nucleoids were stained with SYBR-Green I, and the mitochondria were stained with 3,3-dihexyloxacarbocyanine iodide. An mocG33 mutant, which contains one large chloroplast nucleoid throughout the cell cycle, was used to distinguish between the mitochondrial and chloroplast nucleoids. Changes in the total levels of organellar DNA levels were assessed by real-time PCR. Each of the G1, S, M, and Smt,cp phases was estimated. At the start of the light period, the new daughter cells were in G1 and contained about 30 mitochondrial and 10 chloroplast nucleoids, which were dispersed and had diameters of 0.1 and 0.2 ,m, respectively. During the G1 phase of the light period, and at the start of the S phase, both nucleoids formed short thread-like or bead-like structures, probably divided, and increased continuously in number, concomitantly with DNA synthesis. The nucleoids probably became smaller due to the decrease in DNA of each particle and were indistinguishable. The cells in the S and M phases contained extremely high numbers of scattered nucleoids. However, in the G1 phase of the dark period, the nucleoids again formed short thread-like or bead-like structures, probably fused, and decreased in number. The mitochondria appeared as tangled sinuous structures that extended throughout the cytoplasm and resembled a single large mitochondrion. During the cell cycle, the numbers of mitochondrial nucleoids and sinuous structures varied relative to one another. [source] PYRENOID FORMATION ASSOCIATED WITH THE CELL CYCLE IN THE BROWN ALGA, SCYTOSIPHON LOMENTARIA (SCYTOSIPHONALES, PHAEOPHYCEAE),JOURNAL OF PHYCOLOGY, Issue 6 2003Chikako Nagasato Vegetative cells of the brown alga Scytosiphon lomentaria (Lyngbye) Link characteristically have only one chloroplast with a prominent protruding pyrenoid, whereas zygotes have both paternal and maternal chloroplasts. In zygotes, before cell and chloroplast division, each chloroplast has an old and a new pyrenoid. In this study, we raised a polyclonal antibody to RUBISCO and examined the distribution of RUBISCO by immunofluorescence microscopy, focusing on new pyrenoid formation in vegetative cells of gametophytes and zygotes in Scytosiphon. In interphase, only one old pyrenoid was positively indicated by anti-RUBISCO antibody in vegetative cells of gametophytes. From mid-S phase, small fluorescence aggregates reflecting RUBISCO localization started to appear at stroma positions other than adjacent to the old protruding pyrenoid. The fluorescent spots eventually coalesced into a protrusion into the adjacent cytoplasm. We also used inhibitors to clarify the relationship between the cell cycle and new pyrenoid formation, using zygotes after fertilization. When DNA replication was blocked by aphidicolin, new pyrenoid formation was also inhibited. Washing out aphidicolin permitted new pyrenoid formation with the progression of the cell cycle. When mitosis was prolonged by nocodazole, which disrupted the spindle microtubules, the fluorescent masses indicating RUBISCO localization continued to increase when compared with pyrenoid formation in untreated zygotes. During treatment with chloramphenicol, mitosis and cytokinesis were completed. However, there was no occurrence of new RUBISCO localization within the chloroplast stroma beyond the old pyrenoid. From these observations, it seems clear that new pyrenoid formation in the brown alga Scytosiphon depends on the cell cycle. [source] PHOTOSYNTHETIC FUNCTION IN DUNALIELLA TERTIOLECTA (CHLOROPHYTA) DURING A NITROGEN STARVATION AND RECOVERY CYCLEJOURNAL OF PHYCOLOGY, Issue 5 2003Erica B. Young Phytoplankton can be exposed to periods of N starvation with episodic N resupply. N starvation in Dunaliella tertiolecta (Butcher) measured over 4 days was characterized by slow reduction in cell chl and protein content and chl/carotenoid ratio and a decline in photosynthetic capacity and maximum quantum yield of photosynthesis (Fv/Fm). In the early stages of N starvation, cell division was maintained despite reduction in cellular chl. Chl content was more sensitive than carotenoids to N deprivation, and cellular chl a was maintained preferentially over chl b under N starvation. NO3, resupply stimulated rapid and complete recovery of Fv/Fm (from 0.4 to 0.7) within 24 h and commencement of cell division after 10 h, although N-replete levels of cell chl and protein were not reestablished within 24 h. Recovery of Fv/Fm was correlated with increases in cell chl and protein and was more related to increases in Fm than to changes in F0. Recovery of Fv/Fm was biphasic with a second phase of recovery commencing 4,6 h after resupply of NO3,. Uptake of NO3, from the external medium and the recovery of Fv/Fm, cell chl, and protein were inhibited when either cytosolic or chloroplastic protein synthesis was inhibited by cycloheximide or lincomycin, respectively; a time lag observed before maximum NO3, uptake was consistent with synthesis of NO3, transporters and assimilation enzymes. When both chloroplastic and cytosolic translation was inhibited, Fv/Fm declined dramatically. Dunaliella tertiolecta demonstrated a capacity to rapidly reestablish photosynthetic function and initiate cell division after N resupply, an important strategy in competing for limiting inorganic N resources. [source] UNCOUPLING OF SILICON COMPARED WITH CARBON AND NITROGEN METABOLISMS AND THE ROLE OF THE CELL CYCLE IN CONTINUOUS CULTURES OF THALASSIOSIRA PSEUDONANA (BACILLARIOPHYCEAE) UNDER LIGHT, NITROGEN, AND PHOSPHORUS CONTROL1JOURNAL OF PHYCOLOGY, Issue 5 2002Pascal Claquin The elemental composition and the cell cycle stages of the marine diatom Thalassiosira pseudonana Hasle and Heimdal were studied in continuous cultures over a range of different light- (E), nitrogen- (N), and phosphorus- (P) limited growth rates. In all growth conditions investigated, the decrease in the growth rate was linked with a higher relative contribution of the G2+M phase. The other phases of the cell cycle, G1 and S, showed different patterns, depending on the type of limitation. All experiments showed a highly significant increase in the amount of biogenic silica per cell and per cell surface with decreasing growth rates. At low growth rates, the G2+M elongation allowed an increase of the silicification of the cells. This pattern could be explained by the major uptake of silicon during the G2+M phase and by the independence of this process on the requirements of the other elements. This was illustrated by the elemental ratios Si/C and Si/N that increased from 2- to 6-fold, depending of the type of limitation, whereas the C/N ratio decreased by 10% (E limitation) or increased by 50% (P limitation). The variations of the ratios clearly demonstrate the uncoupling of the Si metabolism compared with the C and N metabolisms. This uncoupling enabled us to explain that in any of the growth condition investigated, the silicification of the cells increased at low growth rates, whereas carbon and nitrogen cellular content are differently regulated, depending of the growth conditions. [source] CYST,THECA RELATIONSHIP, LIFE CYCLE, AND EFFECTS OF TEMPERATURE AND SALINITY ON THE CYST MORPHOLOGY OF GONYAULAX BALTICA SP.JOURNAL OF PHYCOLOGY, Issue 4 2002NOV. (DINOPHYCEAE) FROM THE BALTIC SEA AREA A new species of Gonyaulax, here named Gonyaulax baltica sp. nov., has been isolated from sediment samples from the southeastern Baltic. Culture strains were established from individually isolated cysts, and cyst formation was induced in a nitrogen-depleted medium. Although G. baltica cysts are similar to some forms attributed to Spiniferites bulloideus and the motile stage of G. baltica has affinities with G. spinifera, the combination of features of cyst and motile stage of G. baltica is unique. The culture strains were able to grow at salinity levels from 5 to 55 psu and formed cysts from 10 to 50 psu. Cultures at each salinity level were grown at 12, 16, and 20° C. Temperature- and salinity-controlled morphological variability was found in the resting cysts. Central body size varied with temperature and salinity, and process length varied with salinity. Cysts that formed at extreme salinity levels displayed lower average process length than cysts formed at intermediate salinity levels, and central body length and width were lowest at higher temperature and lower salinity. Models for the relationship between central body size and temperature/salinity and process length and salinity have been developed and may be used to determine relative paleosalinity and paleotemperature levels. Our results on salinity-dependent process length confirm earlier reports on short-spined cysts of this species found in low salinity environments, and the model makes it possible to attempt to quantify past salinity levels. [source] UNEMPLOYMENT DURATION, BENEFIT DURATION AND THE BUSINESS CYCLETHE ECONOMIC JOURNAL, Issue 479 2002Olympia Bover In this paper we study the effects of unemployment benefit duration and the business cycle on unemployment duration. We construct durations for individuals entering unemployment from a longitudinal sample of Spanish men in 1987,94. Estimated discrete hazard models indicate that receipt of unemployment benefits significantly reduces the hazard of leaving unemployment. At durations of three months, when the largest effects occur, the hazard for workers without benefits is twice as large as that for workers with benefits. Favourable business conditions increase the hazard of leaving unemployment. At sample-period magnitudes, this effect is significantly smaller than that of benefit receipt. [source] FOOD INSECURITY IN BUHAYA: THE CYCLE OF WOMEN'S MARGINALIZATION AND THE SPREAD OF POVERTY, HUNGER, AND DISEASEANNALS OF ANTHROPOLOGICAL PRACTICE, Issue 1 2009Valerie Githinji This chapter focuses on how the marginalization of Bahaya women increases poverty, thus exacerbating issues of hunger and related disease in a region characterized by a history of environmental degradation, agricultural change and decline, rural poverty and disease. In the past several decades, diminishing sizes of banana farms, an overall decline in cattle, decreasing soil fertility, and an increase in food crop pathogens have posed challenges to achieving adequate agricultural yields in Buhaya of northwestern Tanzania. This situation has resulted in an increase in poverty, food insecurity, nutrition insecurity, and related disease. Culturally, women are the primary agriculturalists and producers and providers of food in Buhaya. However, Bahaya cultural practices hinder women from achieving equal representation in society, thus blocking their access to self advancement and resources such as money, land, education, and agricultural inputs. These constraints marginalize and hinder women from fulfilling their social role as primary farmers and provisioners of food, nutrition, and care. As patriarchal practices and ecological challenges work to constrain women's roles, poverty, food scarcity, and disease increase, affecting and weakening the foundation of Bahaya society and culture. [source] A SECOND CYCLE OF TAMSULOSIN IN PATIENTS WITH DISTAL URETERIC STONES: A PROSPECTIVE RANDOMIZED TRIALBJU INTERNATIONAL, Issue 12 2009Gianluca Giannarini No abstract is available for this article. [source] POLITICAL MONETARY CYCLES UNDER ALTERNATIVE INSTITUTIONS: THE INDEPENDENT TREASURY AND THE FEDERAL RESERVEECONOMICS & POLITICS, Issue 3 2005Jac C. Heckelman The theory of opportunistic political business cycles predicts incumbent politicians will alter their economic policies to spur short-run growth to attract additional votes for the upcoming election. There has not been much emphasis on the possibility of historical political business cycles prior to the Keynesian Revolution. No study has yet undertaken a systematic approach to testing for policy cycles during this period. Our study will bridge this gap by considering cycles in monetary policy for the periods of 1879,1914 until the start of Fed operations, and 1914,1932 until abandonment of the gold standard. To properly test for political cycles, it is necessary to develop reaction functions for the Treasury and compare against the reaction function later held by the Fed. This also reveals that creation of an independent monetary authority to be insulated from political pressures changed the manner in which policy was directed, aside from political issues. The evidence is not consistent, however, with monetary cycles closely tied to electoral concerns. [source] HISTORIC CYCLES OF FRAGMENTATION AND EXPANSION IN PARNASSIUS SMINTHEUS (PAPILIONIDAE) INFERRED USING MITOCHONDRIAL DNAEVOLUTION, Issue 1 2004Eric G. DeChaine Abstract Climate oscillations of the Quaternary drove the repeated expansion and contraction of ecosystems. Alpine organisms were probably isolated in sky island refugia during warm interglacials, such as now, and expanded their range by migrating down-slope during glacial periods. We used population genetic and phylogenetic approaches to infer how paleoclimatic events influenced the distribution of genetic variation in the predominantly alpine butterfly Parnassius smintheus. We sequenced a 789 bp region of cytochrome oxidase I for 385 individuals from 20 locations throughout the Rocky Mountains, ranging from southern Colorado to northern Montana. Analyses revealed at lease two centers of diversity in the northern and southern Rocky Mountains and strong population structure. Nested clade analysis suggested that the species experienced repeated cycles of population expansion and fragmentation. The estimated ages of these events, assuming a molecular clock, corresponded with paleoclimatic data on habitat expansion and contraction over the past 400,000 years. We propose that alpine butterflies persisted in an archipelago of isolated sky islands during interglacials and that populations expanded and became more connected during cold glacial periods. An archipelago model implies that the effects of genetic drift and selection varied among populations, depending on their latitude, area, and local environment. Alpine organisms are sensitive indicators of climate change and their history can be used to predict how high-elevation ecosystems might respond to further climate warming. [source] SEASONAL CYCLES OF ALLOZYME-BY-CHROMOSOMAL-INVERSION GAMETIC DISEQUILIBRIUM IN DROSOPHILA SUBOBSCURAEVOLUTION, Issue 4 2003Francisco Rodríguez-Trelles Abstract Allozyme loci are frequently found non randomly associated to the chromosomal inversions in which they are included in Drosophila. Two opposite views compete to explain strong allozyme-by-inversion gametic disequilibria: they result from natural selection or, conversely, merely represent remnants of associations accidentally established at the origin of inversions. Empirical efforts aimed at deciding between adaptive and historical scenarios have focused on the spatial distribution of disequilibria. Yet, the evolutionary significance of these associations remains uncertain. I report here the results of a time-series analysis of the seasonal variation of alleles at six allozyme loci (Acph, Lap, Pept-1, Ao, Mpi, and Xdh) in connection with the O chromosomal polymorphisms of D. subobscura. The findings were: (1) in the segment I of the O chromosome, Lap and Pept-1 allozymes changed seasonally in a cyclical fashion within the ST gene arrangement, but they changed erratically within the 3+4 gene configuration; (2) the frequencies of Lap111 and Pept-10,40 within ST dropped to their lowest values in early and late summer, respectively, when the seasonal level of the ST arrangement is lowest. Furthermore, Lap1,11 and Pept-10,40 covary with ST only within these seasons, yet in a fashion inconsistent with these alleles having a major influence on the dynamics of the inversion; (3) seasonal cycling of alleles within inversions were not detected at Acph, Ao, Mpi, and Xdh, yet these loci are nearly monomorphic at the study population, and/or their sampled series were shorter than those for Lap and Pept-1; and (4) simply monitoring allozyme frequencies separately for each inversion proved to be superior, for evidencing the seasonal cycles of the disequilibria, to the use of the D' coefficient of association. Observed seasonal cycles of allozymes within inversions likely reflect natural selection. [source] WILL BUSINESS CYCLES IN THE EURO AREA CONVERGE?JOURNAL OF ECONOMIC SURVEYS, Issue 2 2008A CRITICAL SURVEY OF EMPIRICAL RESEARCH Abstract This survey of business cycle synchronization in the European monetary union focuses on two issues: have business cycles become more similar, and which factors drive business cycle synchronization. We conclude that business cycles in the euro area have gone through periods of both convergence and divergence. Still, there is quite some evidence that during the 1990s business cycle synchronization in the euro area has increased. Higher trade intensity is found to lead to more synchronization, but the point estimates vary widely. The evidence for other factors affecting business cycle synchronization is very mixed. [source] TEXTURE STABILITY OF HYDROGEL COMPLEX CONTAINING CURDLAN GUM OVER MULTIPLE FREEZE,THAW CYCLESJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 1 2009PATRICK D. WILLIAMS ABSTRACT The texture stability of hydrogel complexes containing curdlan gum over multiple freeze,thaw cycles (FTCs) was investigated. The hydrogels formed by curdlan and xanthan gum, locust bean gum, carrageenan or guar gum at various combinations were stored at 4C for 24 h before subjected to five FTCs alternating between,16 (18 h) and 25C (6 h). Xanthan/curdlan hydrogels showed the highest freeze,thaw stability in terms of syneresis, heat stability and adhesiveness. The viscosity of xanthan/curdlan combination was the lowest among all samples studied yet the most stable over the five FTCs, whereas significant changes were observed with locust bean/curdlan hydrogels. The guar/curdlan combination before freeze,thaw treatments exhibited predominant elasticity; however, as the cycles progressed the elasticity decreased. The most stable gel strength was achieved when curdlan was combined with guar or xanthan at 2% (w/v) total concentration, while carrageenan/curdlan gels were the least stable. PRACTICAL APPLICATIONS Texture instability remains the most significant challenge for frozen food products, especially with inevitable post-production temperature fluctuations. Loss of moisture and changes in textural attributes often results in significant reduction of product quality. Precise control of hydrogel complexes that provide texture stabilization over multiple freeze,thaw cycles will enhance the quality of existing products while enabling the development of new ones. [source] QUALITY CHANGES IN AUSTRALIAN RED CLAW CRAYFISH (CHERAX QUADRICARINATUS) SUBJECTED TO MULTIPLE FREEZING-THAWING CYCLES,JOURNAL OF FOOD QUALITY, Issue 4 2003YEN-CHANG TSENG For each F/T cycle, five raw tails were analyzed for lipid oxidation, proteolysis, and thermal stability, and another five tails were cooked to determine cooking yield and tenderness (shear). Lipid oxidation occurred during repeated F/T treatment, as evidenced by a marked TBARS increase, i.e., from 0.070 mg/kg (fresh) to 1.201 mg/kg (cycle 6). While F/T induced small proteolytic and thermal stability changes, it caused a major loss in cooking yield as well as in tenderness of meat. The results showed an overall susceptibility of the main quality traits of red claw muscle to F/T abuses. Thus, to retain good eating qualities, red claw tails should not be subjected to more than three F/T cycles. [source] HABITAT DIFFERENCES IN THE TIMING OF REPRODUCTION OF THE INVASIVE ALGA SARGASSUM MUTICUM (PHAEOPHYTA, SARGASSACEAE) OVER TIDAL AND LUNAR CYCLES,JOURNAL OF PHYCOLOGY, Issue 1 2009Carla Monteiro Sargassum muticum (Yendo) Fensholt is an invasive species that is firmly established on intertidal and subtidal rocky shores of Europe and the Pacific coast of North America. Local success and spread of S. muticum is thought to rely on its reproductive potential that seems dependent on exogenous factors like tidal and lunar cycles. This study is the first to compare the reproductive patterns (periodicity of egg expulsion and embryo settlement) of this invader in two different habitats: the middle and low intertidal. The combination of monthly, daily, and tidal samples at triplicate sites within each habitat showed a semilunar periodicity of egg expulsion and embryo settlement coincident with increasing tidal amplitude just before full and new moons. In both habitats, duration of each egg expulsion event was ,1 week, and embryo settlement occurred during the first daily low tide and with the incoming high tide during spring tides. However, both expulsion and settlement started 1,2 d earlier, expulsion saturation was faster, and settlement was higher in the mid- compared to the low intertidal. Our results suggest that the exact timing of gamete expulsion and embryo release of S. muticum responds to local factors, including tidal cues, which result in differences between mid- and low-intertidal habitats. [source] SHORT-TERM CYCLES IN PRIMARY COMMODITY PRICESTHE DEVELOPING ECONOMIES, Issue 3 2000Walter C. LABYS First page of article [source] PRODUCTIVITY AND BUSINESS CYCLES IN JAPAN: EVIDENCE FROM JAPANESE INDUSTRY DATA,THE JAPANESE ECONOMIC REVIEW, Issue 2 2006T. MIYAGAWA Constructing a database of 37 industries, we examine whether the measured productivity in Japan is pro-cyclical and investigate the sources of this pro-cyclicality by using the production function approach employed by Hall (1990) and Basu and Fernald (1995). The aggregate Solow residual displays pro-cyclicality. A large number of industries show constant returns to scale. No significant evidence for the presence of thick-market externalities is found. Our results also hold when we consider labour hoarding, part-time employment, and the adjustment cost of investment. The results indicate that policies to revitalize the Japanese economy should concentrate on promoting productivity growth. [source] COMMENT: PRODUCTIVITY AND BUSINESS CYCLES IN JAPAN: EVIDENCE FROM JAPANESE INDUSTRY DATA,THE JAPANESE ECONOMIC REVIEW, Issue 2 2006TOMOYUKI NAKAJIMA First page of article [source] INNOVATION CYCLES AND LEARNING AT THE PATENT OFFICE: DOES THE EARLY PATENT GET THE DELAY?,THE JOURNAL OF INDUSTRIAL ECONOMICS, Issue 2 2010PIERRE RÉGIBEAU We study the relationship between the length of patent review and the importance of inventions. We build a simple model of the U.S. patent review process. Among the model predictions are that, controlling for a patent's position in a new technology cycle, more important innovations would be approved more quickly. Also, the approval delay is likely to decrease as an industry moves from the early stages of an innovation cycle to later stages. These predictions are in line with the evidence we obtain from a data set on U.S. patents granted in the field of genetically modified crops from 1983 to 1999. We also show that failing to account for the innovation lifecycle , as previous studies have done , is likely to bias upwards the estimates of the relationship between delay and importance. [source] THE DECLINE IN THE VOLATILITY OF THE BUSINESS CYCLES IN THE UKTHE MANCHESTER SCHOOL, Issue 2008CHRISTINA V. ATANASOVA We analyse the sources of the decline of business cycle volatility in the UK using a dynamic factor model that allows for the presence of a structural break in the conditional mean and variance of output, sales, income and unemployment. We augment the factor model with an economic component to investigate the role of structural changes and improved monetary policy in the volatility decline of the series. Our results suggest that the dominant cause for the observed volatility decline is the reduced variability of shocks. [source] DISTRIBUTIONAL CONFLICT, POLITICAL CYCLES AND GROWTHTHE MANCHESTER SCHOOL, Issue 4 2005CHRISTIANE CLEMENS This paper discusses the emergence of endogenous redistributive cycles in a stochastic growth model with incomplete asset markets and heterogeneous agents who vote on the degree of progressivity in the tax-transfer scheme. The model draws from Bénabou (in B. S. Bernanke and J. J. Rotemberg (eds), NBER Macroeconomics Annual, Vol. 11, Cambridge, MA, MIT Press, pp. 11,74) and ties the bias in the distribution of political power to the degree of inequality in the society, thereby triggering redistributive cycles which then give rise to a nonlinear, cyclical pattern of savings rates, growth and inequality over time. [source] ENDOGENOUS BUSINESS CYCLES: THE INFLUENCE OF CHARACTER TRAITS,AUSTRALIAN ECONOMIC PAPERS, Issue 1 2009FUJIO TAKATA This article deals with how business cycles can occur, in light of character traits which influence individual behaviour in an economy. We assume an overlapping generations model in which every consumer has identical instantaneous utility which is additively separable with respect to time. The parameters of utility here include character traits which influence the choice between consumption and savings. In this situation, young individuals choose between current consumption and current savings which lead to future consumption in their old age. Individual character traits, which appear both in the shape of utility functions and in evaluations about utility in the future, affect these choices. And since these choices determine savings, individual character traits can eventually determine how our economy moves. Focusing on the relationship between individual character traits and savings formation, we demonstrate that endogenous business cycles with two periods can occur, in an economy comprised of individuals who opt for current consumption and who are careless in relation to future events, like Aesopian grasshoppers, and in other cases they do not. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||