1,257 research outputs found
Dynamic performance of hierarchical planning systems : modeling and evaluation with dynamic planned lead times
Multiscale Systematic Risk
Cataloged from PDF version of article.In this paper we propose a new approach to estimating systematic risk (the beta of an asset). The proposed method is based on a wavelet multiscaling approach that decomposes a given time series on a scale-by-scale basis. The empirical results from different economies show that the relationship between the return of a portfolio and its beta becomes stronger as the wavelet scale increases. Therefore, the predictions of the CAPM model should be investigated considering the multiscale nature of risk and return. (C) 2004 Elsevier Ltd. All rights reserved
Effects of various inulin levels on in vitro digestibility of corn silage, perennial ryegrass (Lolium perenne L.) and common vetch (Vicia sativa L.)/oat (Avena sativa L.) hay
The aim of this study was to investigate the effects of various inulin levels on in vitro true dry matter digestibility (IVTDDM) and in vitro neutral detergent fibre digestibility (IVTDNDF) of corn silage (CS), perennial ryegrass (PR), and common vetch/oat hay (VO). Inulin was added to the fermenter at concentrations of 0 (CSC, PRC, VOC), 100 (CS100, PR100, VO100), 200 (CS200, PR200, VO200), and 300 (CS300, PR300, VO300) mg/litre of total culture fluid using an in vitro DaisyII incubator. Each fermenter contained 1600 ml buffer solution and 400 ml rumen fluid. The IVTDDM and IVTDNDF were determined with a DaisyII incubator and rumen fluid obtained from three cannulated Karayaka rams. The IVTDDM values (%) for PRC, PR100, PR200, and PR300 were 70.06 ± 1.133, 73.21 ± 4.153, 70.36 ± 0.506, and 66.69 ± 1.317, respectively. The effects of various inulin levels on IVTDDM and IVTDNDF values of PR were significant (P <0.05). The IVTDDM and IVTDNDF values for CS and VO were not significantly (P >0.05) different. Among the treatments, supplementation of inulin to CS and VO did not have a significant (P >0.05) effect on IVTDDM and IVTDNDF values. The high dose of inulin (PR300) reduced IVTDDM and IVTDNDF, whereas PR100 showed a statistically significant (P <0.05) increase on IVTDDM and IVTDNDF. However, in vivo studies with PR may be required to show the effects of various levels of inulin supplementation to support the IVTD findings of the current study.Keywords: Inulin, in vitro true digestibility, hay, silag
Between a rock and a hard place: corporate elites in the context of religion and secularism in Turkey
Drawing on discourse analyses of 36 in-depth interviews with elite business people from Turkey, the study identifies the networking patterns of new and established business elites in the context of economic liberalization and socioreligious transformation of the country. Through a comparative analysis of the so-called secular and religious elite networks, we demonstrate the role of institutional actors such as the government, and identity networks, based on religion and place of birth in shaping the form and content of social networks among business elites in Turkey. In order to achieve this, we operationalize Bourdieu's notion of theory of practice and Granovetter's theory of social networks, illustrating the utility of combining these approaches in explicating the form and content of social networks in their situated contexts, in which power and divergent interests are negotiated.Galatasaray University Research Fund [grant number 12.102.005]
Fixed vs. Flexible Pricing in a Competitive Market
We study the selection and dynamics of two popular pricing policies—fixed price and flexible price—in competitive markets. Our paper extends previous work in marketing, for example, Desai and Purohit (2004) by focusing on decentralized markets with a dynamic and fully competitive framework while also considering possible noneconomic aspects of bargaining. We construct and analyze a competitive search model, which allows us to endogenize the expected demand depending on pricing rules and posted prices. Our analysis reveals that fixed and flexible pricing policies generally coexist in the same marketplace, and each policy comes with its own list price and customer demographics. More specifically, if customers dislike haggling, then fixed pricing emerges as the unique equilibrium, but if customers get some additional satisfaction from the bargaining process, then both policies are offered, and the unique equilibrium exhibits full segmentation: haggler customers avoid fixed-price firms and exclusively shop at flexible firms, whereas nonhaggler customers do the opposite. We also find that prices increase in customer satisfaction, implying that sellers take advantage of the positive utility enjoyed by hagglers in the form of higher prices. Finally, considering the presence of seasonal cycles in most markets, we analyze a scenario in which market demand goes through periodic ups and downs and find that equilibrium prices remain mostly stable despite significant fluctuations in demand. This finding suggests a plausible competition-based explanation for the stability of prices
Ekspresija E-selektina u mišjem sjemeniku nakon njegove pokusne torzije (ishemije/reperfuzije).
Germ cell-specific apoptosis occurs after ischemia/reperfusion of the testis and is dependent on E-selectin expression. The aim of the study was to determine differences in E-selectin expression in testes tissues of control, sham and treatment groups after ischemia/reperfusion in mice. Mice were subjected to 720° testicular torsion for 1 h or 2 h duration (ischemia) followed by detorsion (reperfusion). After 2 h of reperfusion, the testes were fixed in Bouin fixative and immunohistochemical analysis performed for E-Selectin expression. E-selectin expression increased in the ischemic testis and contralateral testis after 2 h of reperfusion in mice. This increase in E-selectin expression may confirm that E-selectins play a key role in mediating of apoptosis in germ cells after ischemia/reperfusion. Thus, the blockage of E-selectins might be a strategy for rescue of post-ischemic testes.Apoptoza germinativnih stanica javlja se nakon ishemije i reperfuzije sjemenika, a ovisna je o ekspresiji E-selektina. Cilj ovog istraživanja bio je odrediti razlike u ekspresiji E-selektina u tkivu sjemenika kontrolne, placebo i pokusne skupine nakon ishemije/reperfuzije u miševa. Miševi su bili podvrgnuti torziji sjemenika od 7200 tijekom jednog ili dva sata (ishemija), nakon čega je slijedila detorzija (reperfuzija). Nakon dva sata reperfuzije tkivo sjemenika bilo je fiksirano u Bouinovom fiksativu i pretraženo imunohistokemijski na ekspresiju E-selektina. Ekspresija E-selektina povećala se u ishemičnih sjemenika nakon dva sata reperfuzije. Može se reći da povećanje ekspresije E-selektina potvrđuje njhovu ključnu ulogu u nastanku apoptoze germinativnih stanica nakon ishemije/reperfuzije pa bi blokada E-selektina mogla biti od važnosti za spašavanje sjemenika nakon ishemije
Perceived partner responsiveness, daily negative affect reactivity, and all-cause mortality:A 20-year longitudinal study
Objective This study tested longitudinal associations between absolute levels of perceived partner responsiveness (PPR; how much people perceive that their romantic partners understand, care for, and appreciate them), daily negative affect reactivity and positive affect reactivity, and all-cause mortality in a sample of 1,208 adults for three waves of data collection spanning 20 years. We also tested whether longitudinal changes in PPR predicted mortality via affect reactivity. Methods Data were taken from the National Survey of Midlife Development in the United States. PPR was assessed at waves 1 and 2, affect reactivity to stressors was assessed by daily diary reports at wave 2, and mortality status was obtained at wave 3. Results Mediation analyses revealed absolute levels of PPR at wave 1 predicted wave 3 mortality via wave 2 affective reactivity in the predicted direction, but this did not remain robust when statistically accounting for covariates (e.g., marital risk, neuroticism), beta = .004, 95% confidence interval = -.03 to .04. However, wave 1-2 PPR change predicted negative affect (but not positive affect) reactivity to daily stressors at wave 2, which then predicted mortality risk a decade later (wave 3); these results held when adjusting for relevant demographic, health, and psychosocial covariates, beta = -.04, 95% confidence interval = -.09 to -.002. Conclusions These findings are among the first to provide direct evidence of psychological mechanisms underlying the links between intimate relationships and mortality and have implications for research aiming to develop interventions that increase or maintain responsiveness in relationships over time
CHIMP: A Framework for Multimedia Documents
A multimedia document consists of different types of media objects that are to be presented at different instants of time and for different durations. The media objects may be stored in computer systems connected by a network, thereby rendering the document distributed. The authors may wish to collaborate in a distributed manner to edit a multimedia document. Hence, an authoring system needs to identify a retrieval schedule that describes the time instants at which the objects have to be retrieved as well as the logical paths to be followed by the objects. In this paper, we consider a collaborative multimetia document authoring system with the above mentioned features. We propose a difference constraints based temporal specification for the multimedia document. This approach allows us to generate flexible schedules for retrieving objects over the computer network. This flexible retrieval schedule can handle variations in system parameters such as available network throughput and buffer resources
Full Electrostatic Control of Nanomechanical Buckling
Buckling at the micro and nanoscale generates distant bistable states which
can be beneficial for sensing, shape-reconfiguration and mechanical computation
applications. Although different approaches have been developed to access
buckling at small scales, such as the use heating or pre-stressing beams, very
little attention has been paid so far to dynamically and precisely control all
the critical bifurcation parameters, the compressive stress and the lateral
force on the beam. Precise and on-demand generation of compressive stress on
individually addressable microstructures is especially critical for
morphologically reconfigurable devices. Here, we develop an all-electrostatic
architecture to control the compressive force, as well as the direction and
amount of buckling, without significant heat generation on micro/nano
structures. With this architecture, we demonstrated fundamental aspects of
device function and dynamics. By applying voltages at any of the digital
electronics standards, we have controlled the direction of buckling. Lateral
deflections as large as 12% of the beam length were achieved. By modulating the
compressive stress and lateral electrostatic force acting on the beam, we tuned
the potential energy barrier between the post-bifurcation stable states and
characterized snap-through transitions between these states. The proposed
architecture opens avenues for further studies that can enable efficient
actuators and multiplexed shape-shifting devices
The effects of seasonal variation on the microbial-n flow to the small intestine and prediction of feed intake in grazing karayaka sheep
The objectives of the present study were to estimate the microbial-N flow to the small intestine and to predict the digestible
organic matter intake (DOMI) in grazing Karayaka sheep based on urinary excretion of purine derivatives (xanthine, hypoxanthine, uric
acid and allantoin) by the use of spot urine sampling under field conditions. In the trial, 10 Karayaka sheep from 2 to 3 years of age
were used. The animals were grazed in a pasture for ten months and fed with concentrate and vetch plus oat hay for the other two
months (January and February) indoors. Highly significant linear and cubic relationships (P<0.001) were found among months for
purine derivatives index, purine derivatives excretion, purine derivatives absorption, microbial-N and DOMI. Through urine sampling
and the determination of levels of excreted urinary PD and the Purine Derivatives:Creatinine ratio (PDC index), microbial-N values were
estimated and they indicated that the protein nutrition of the sheep was insufficient. In conclusion, the prediction of protein nutrition
of sheep under the field conditions may be possible with the use of spot urine sampling, urinary excreted PD and PDC index. The
mean purine derivative levels in spot urine samples from sheep were highest in June, July and October. Protein nutrition of pastured
sheep may be affected by weather changes, including rainfall. Spot urine sampling may useful in modeling the feed consumption of
pasturing sheep. However, further studies are required under different field conditions with different breeds of sheep to develop spot
urine sampling as a model
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