875 resultados para Osmotic adjustment
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In wireless ad hoc sensor networks, energy use is in many cases the most important constraint since it corresponds directly to operational lifetime. Topology management schemes such as GAF put the redundant nodes for routing to sleep in order to save the energy. The radio range will affect the number of neighbouring nodes, which collaborate to forward data to a base station or sink. In this paper we study a simple linear network and deduce the relationship between optimal radio range and traffic. We find that half of the power can be saved if the radio range is adjusted appropriately compared with the best case where equal radio ranges are used.
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The accumulation and transport of solutes are hallmarks of osmoadaptation. In this study we have employed the inability of the Saccharomyces cerevisiae gpd1Δ gpd2Δ mutant both to produce glycerol and to adapt to high osmolarity to study solute transport through aquaglyceroporins and the control of osmostress-induced signaling. High levels of different polyols, including glycerol, inhibited growth of the gpd1Δ gpd2Δ mutant. This growth inhibition was suppressed by expression of the hyperactive allele Fps1-AΔ of the osmogated yeast aquaglyceroporin, Fps1. The degree of suppression correlated with the relative rate of transport of the different polyols tested. Transport studies in secretory vesicles confirmed that Fps1-Δ1 transports polyols at increased rates compared with wild type Fps1. Importantly, wild type Fps1 and Fps1-Δ1 showed similarly low permeability for water. The growth defect on polyols in the gpd1Δ gpd2Δ mutant was also suppressed by expression of a heterologous aquaglyceroporin, rat AQP9. We surmised that this suppression was due to polyol influx, causing the cells to passively adapt to the stress. Indeed, when aquaglyceroporin-expressing gpd1Δ gpd2Δ mutants were treated with glycerol, xylitol, or sorbitol, the osmosensing HOG pathway was activated, and the period of activation correlated with the apparent rate of polyol uptake. This observation supports the notion that deactivation of the HOG pathway is closely coupled to osmotic adaptation. Taken together, our "conditional" osmotic stress system facilitates studies on aquaglyceroporin function and reveals features of the osmosensing and signaling system. © 2005 by The American Society for Biochemistry and Molecular Biology, Inc.
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A simple elementary osmotic pump (EOP) system that could deliver metformin hydrochloride (MT) and glipizide (GZ) simultaneously for extended periods of time was developed in order to reduce the problems associated with multidrug therapy of type 2 non-insulin-dependent diabetes mellitus. In general, both highly and poorly water-soluble drugs are not good candidates for elementary osmotic delivery. However, MT is a highly soluble drug with a high dose (500 mg) while GZ is a water-insoluble drug with a low dose (5 mg) so it is a great challenge to pharmacists to provide satisfactory extended release of MT and GZ. In this paper sodium carbonate was used to modulate the solubility of GZ within the core and MT was not only one of the active ingredients but also the osmotic agent. The optimal EOP was found to deliver both drugs at a rate of approximately zero order for up to 10 h in pH 6.8, independent of environment media. In-vivo evaluation was performed relative to the equivalent dose of conventional MT tablet and GZ tablet by a cross-study in six Beagle dogs. The EOP had a good sustained effect in comparison with the conventional product. The prototype design of the system could be applied to other combinations of drugs used for cardiovascular diseases, diabetes, etc.
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In this paper a mathematical model based on mass transfer in plant tissues is developed. The model takes into account the diffusion and convection of each constituent within the tissue. The driving force for the convection is assumed to be the gradient of hydrostatic pressure. The mass balance equation for the transport of each constituent is established separately for intracellular and extracellular volumes but taking into account the mass exchange across the cell membrane between the intracellular and extracellular volumes. The mass transfer results in not only the change of intracellular and extracellular volumes but also the shrinkage of whole tissue. The model allows us to quantitatively simulate the time evolution of intracellular and extracellular volumes, which was observed in histological sections under the microscope. © 2005 Elsevier B.V. All rights reserved.
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This research tests the role of perceived support from multinational corporations and host-country nationals for the adjustment of expatriates and their spouses while on international assignments. The investigation is carried out with matched data from 134 expatriates and their spouses based in foreign multinationals in Malaysia. The results highlight the different reliance on support providers that expatriates and their accompanying spouses found beneficial for acclimatizing to the host-country environment. Improved adjustment in turn was found to have positive effects on expatriates' performance. The research findings have implications for both international human resource management researchers and practitioners. © 2014 © 2014 Taylor & Francis.
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The current world economic crisis induced countries to launch wide-scale spending programmes all over the world. Member states of the European Union have not been an exception to this trend. While deficit spending may increase the aggregate demand, it can also accelerate indebtedness and make the required spending cuts politically risky later on. However, deficit financing is not a new phenomenon in the EU; it has been widely practiced in the last couple of decades. As the crisis seems to come to an end, countries with huge deficits should adopt exit strategies now, thereby reducing deficit and debt and reintroducing fiscal discipline, a requirement laid down in the Stability and Growth Pact. Nevertheless, former adjustment processes can provide ample evidence for successful and politically viable fiscal consolidations. In certain cases, even economic activity started to accelerate as a response to the welldesigned adjustment measures. Based on the previous experiences of EU states, the aim of this paper is, therefore, to identify the conditions that may determine a fiscal consolidation to be successful in terms of a reduced debt ratio and a positive economic growth.
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1995. március 12-én a magyar kormány és a központi bank szigorú kiigazítási és stabilizációs programot hirdetett meg. A cikk az első eredmények számbavételére tesz kísérletet. A program meghirdetése előtt Magyarország két egymást követő év- ben hatalmas fizetésimérleg-hiányt mutatott fel, és nemzetközi megítélése romlani kezdett. A program radikális intézkedései nyomán elkerülhetővé vált a mexikói vál- sághoz hasonló pénzügyi katasztrófa. Sok makrogazdasági mutató jól érzékelhető javulást jelez: lényegesen csökkent a kereskedelmi mérleg és a folyó fizetési mérleg hiánya, a költségvetés elsődleges egyenlege pozitív lett. Az ilyesféle stabilizációs programokat rendszerint súlyos visszaesés és a munkanélküliség nagy növekedése kíséri. Magyarország elkerülte ezeket a mellékhatásokat: a GDP drasztikus vissza- esés helyett valamelyest tovább növekedett, és a munkanélküliség változatlan ma- radt. A javulásnak nagy ára volt: az életszínvonal erőteljes csökkenése, az infláció felgyorsulása, bár a magyarországi infláció még mindig a kézben tartott, mérsékelt infláció sávjában maradt. A cikk ismerteti a program heterodox módszereit: 1. nagy leértékelés, az előre meghirdetett csúszó árfolyam rezsimjének bevezetése, valamint ideiglenes import- vámpótlék kivetése; 2. határozott jövedelempolitika, amely 12 százalékos reálbércsök- kenést kényszerített ki; 3. fiskális intézkedések, köztük jóléti jogosultságok csök- kentése (a program meghirdetése előtt ezek a jogosultságok tabuk voltak); 4. a hitel- kínálat átcsoportosítása a vállalati szektor javára, a jövedelmezőség növekedése; 5. feszített (bár nem mértéktelenül feszített) monetáris politika, amely lehetővé tette a sikeres vállalatok expanzióját; 6. a privatizáció felgyorsítása, nagy és sikeres lépé- sek egyes kulcsszektorok (energia, telekommunikáció) privatizációjában. Végezetül a tanulmány óva int a túlzott magabiztosságtól és felhívja a figyelmet a potenciális veszélyekre. A makrogazdasági javulás még törékeny. A magyar fejlődés legbiztatóbb sajátossága a termelékenység erőteljes és folyamatos növekedése. / === / On March 12, 1995 Hungary s government and central bank announced a tough program of adjustment and stabilization. This study is an attempt to asses the first results. Before the announcement of the program Hungary had a huge current account deficit for two consecutive years, and her international reputation started to decline. The program s radical measures made it possible to avoid a Mexico-style financial catastrophe. Many macroeconomic indicators show tangible improvement: the trade deficit and the deficit on the current account have been reduced significantly, the primary budget shifted to surplus. These kinds of adjustment programs are usually associated with deep recession and a large increase of unemployment. Hungary avoided these adverse side-effects: GDP instead of a drastic decline, continued to grow somewhat, and unemployment remained unchanged. There was a high price for the improvement: a sharp decline in the standard of living, and an acceleration of inflation, although Hungary is still in the range of controlled, moderate inflation. The paper describes the heterodox instruments of the program: (1) large devaluation, followed by a new exchange rate regime of pre-announced crawling peg, and a temporary import surcharge, (2) energetic income policy, enforcing a 12% cut in real wages; (3) fiscal measures, including cuts in welfare entitlements. That happened for the first time: before the program entitlements had been regarded as taboo ; (4) reallocation of credit supply in favor of the enterprise sector; increase of profitability; (5) tight (but not excessively tight) monetary policy, allowing the expansion of successful private busi- ness; (6) acceleration of privatisation, including large and successful steps in the privatisation of some key sectors (energy, telecommunication). Finally the paper warns against excessive self- confidence and draws the attention to potential dangers. The macroeconomic improvement is still fragile. The most reassuring feature of Hungary s development is the impressive and persistent improvement of productivity.
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Az első rész az USA és a legfejlettebb ipari országok, a G7 konjunkturális ingadozásait kívánja értelmezni egy pénzügyileg jóval globalizáltabb világgazdaságban egy hosszabb1970-2010 és egy rövidebb 2001-2010 közötti időszakban. Mindenekelőtt arra keresve választ, hogy mennyire lehetett előre látni a súlyos pénzügyi válság és outputvesztés jövetelét. Továbbá arra, hogy a 2011-ig felgyülemlett empirikus tapasztalatok tükrében vajon beszélhetünk-e egységes, a fejlett ipari országok, /G7/ egészére általában jellemző, és a meghatározó országok esetében is megragadható válságlefolyásról? Megállapíthatók-e olyan univerzálisan megjelenő változások a kibocsátás, a munkapiacok, a fogyasztás, a beruházás tekintetében, amelyek jól illeszkednek a korábbi tapasztalatokhoz, nem kevésbé az ismert makro modellek predikcióihoz? A válasz nemleges. Sem a válság lefolyásának jellegzetességei és a makrogazdasági teljesítmények romlásának ütemei, sem a visszacsúszás mértékei és időbeli kiterjedésében a vizsgált fejlett országok nem mutattak jól azonosítható közös jegyeket, olyanokat, amelyeket a meglévő elméleti keretekbe jól beilleszthetők. A válság lefolyása és mélysége sokféle volt a G7 ország-csoportban. A korábbi válságértelmezések, főleg a pénzügyi csatornák szerepei tekintetében és a nemzetközi konjunkturális összefonódás jelentőségét és mechanizmusait, valamint a globális válságterjedés illetően elégtelennek bizonyultak. A tanulmány áttekinti a válsággal és makrogazdasági sokkokkal foglalkozó empirikus irodalom pénzügyi globalizáció értelmezési nyomán relevánsnak tartott gyakran idézett munkákat. Ezt követően egy hosszú történelemi, a II. vh. utáni 60 év távlatát átfogó vizsgálatban próbáljuk megítélni a recessziós időszakokban az amerikai gazdaság teljesítményét, annak érdekében, hogy az elmúlt válság súlyosságának megítélése legalább a fontosabb makro-változók változásának a nagyságrendje tekintetében a helyére kerüljön. A tartós output rés /output gap/ és munkapiaci eltérések magyarázata más és más elemeket takart az USA-ban, Japánban és Németországban. A pénzügyi csatornákban keletkező, a növekedést és a konjunktúrát érdemben befolyásoló, torzító és sokk-gerjesztő mechanizmusok nem tejesen új-keletűek, az USA-ban. A privát szféra eladósodottsági mutatói - a szövetségi kormány adósság-terheinek cipelésében - a bevett makro felfogással ellentétben - az elmúlt 30 évben nem mutattak szoros és egyirányú (negatív) összefüggést a növekedéssel és recessziókkal. A második rész a pénzügyi globalizáció után kialakult nemzeti alkalmazkodás lehetőségeit vizsgálja, különös tekintettel a kis nyitott gazdaságokra, és így Magyarországra nézve. E tanulmány a globális pénzügyi folyamatok két fontos kérdését taglalja: a nemzetközi tőkeáramlás fokozott liberalizációjából húzható előnyök közgazdasági lényegét; valamint a fokozott nemzetközi tőkeáramláshoz leginkább illeszkedő, „adekvát” árfolyamrendszer kérdését. A következetések részben elméletiek, részben gyakorlatorientáltak. Megerősítésre kerül azon állítás, hogy a tőkeforgalom liberalizációjának és a megvalósítandó árfolyam-politikának a kérdése mind a mai napig erősen problematikus. Sem a tőkeforgalom liberalizációját, sem a megvalósítandó adekvát árfolyamrezsimet illetően nem lehet egységes és elméletileg minden tekintetben megalapozott álláspontról beszélni. Az ún. „lehetetlen szentháromság”, a külföldi és a belföldi célok szimultán követésének különös nehézsége a kis nyitott gazdaságok, és így a magyar gazdaságban még fokozottabban érvényesül. A nemzetközi pénzügyi integráltság magas foka miatt a hagyományos eszközökkel – kamat és fiskális gazdaságélénkítő lépésekkel - nem lehetséges, egy irányba mutató, vagy egymást nem gyengítő, szimultán lépésekkel szabályozni a belföldi és külföldi hitelkeresletet, illetve a konjunktúrát. A kamatpolitika, a forint- és devizahitelezés nehézségei ezt fokozottan illusztrálják Magyarországon is. Ugyanakkor a mindenkori gazdaságpolitika nem bújhat ki azon kényszer alól, hogy egy változó globális pénzügyi környezetben is tatható arányokat találjon a belföldi és a külgazdasági célok között. „Királyi út” azonban nincs a gazdaságpolitika számára. Ez a megállapítás igaz a jegybanki szerepvállalásra is, amely a felduzzadt magyar devizaadósság által okozott bankrendszer szintű kockázatok kezelésére irányul.
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This dissertation identifies, examines, and assesses the relative influence of identified empirically and conceptually relevant variables on incarcerated substance abusers' expectations of postrelease adjustment. A purposive sampling procedure was used to recruit 101 male and female substance-abusing offenders participating in prison- and jail-based drug treatment programs in south Florida. A 92-item survey questionnaire was used to collect basic demographic data; measure inmate preincarceration characteristics, social support, and rehabilitation program participation; and record archival data. Regression equations were developed utilizing ten different measures of the participants' expectations of their postrelease adjustment. Two equations yielded statistically significant F ratios; maintaining a stable living and maintaining abstinence. Twenty-two percent of the variance in respondents' expectations of maintaining a stable living was explained by preincarceration characteristics, social support, and rehabilitation program participation (F = 1.89; df = 13,87; p $<$.05). The only significant predictor variable was perception of social support (b = $-$.05; t = $-$3.6; p $<$.001). Twenty-three percent of the variance in respondents' expectations of maintaining abstinence from substances was explained by preincarceration characteristics, social support, and rehabilitation program participation (F = 2; df = 13,87; p $<$.05). Once again, the only significant predictor variable was perception of social support. The results of the analyses indicate that social support was the only important variable for understanding these respondents' efficacy expectations of postrelease abstinence and stable living. The results of this investigation demonstrate the complexity of the social support variable for prisoners, and identify social support as a potential rehabilitative resource for substance-abusing inmates. The results of this investigation underscore the importance of continued, detailed empirical study in order to understand and clarify how social support, efficacy expectations, and actual postrelease performance interrelate for this population of offenders.
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The purpose of this study was to investigate the relationship between organizational learning and expatriation in overseas subsidiaries as well as in organizations as a whole. In doing so, two issues were addressed--(i) the use of expatriation as firms internationalize, and (ii) the significance of various factors to expatriate success as firms gain international experience. The sample of companies for this study was drawn from U.S. Fortune 500 multinational corporations (MNCs) in two sets of related industries--computers/electronics and petroleum/chemicals. Based on the learning that takes place within organizations as they increase their involvement overseas, a positive relationship was expected between international experience and expatriation when internationalization was low, and a negative relationship was expected when internationalization was high. Results indicate a significant positive relationship between country experience and the proportion of expatriates in that subsidiary when subsidiaries were relatively young, and a negative relationship, however not significant, for more mature subsidiaries. The relationship between overall firm degree of internationalization (DOI) and the proportion of expatriates in the firm as a whole was negative regardless of stage of internationalization, but this relationship was significant only for highly internationalized firms. It was further suspected that individual, environmental, and family-related characteristics would have a significant effect on the success of expatriates whose firms were low on internationalization, and that organizational characteristics would play a significant role in highly internationalized firms. Support for these hypotheses was received with respect to certain outcomes and some determinants of success. The preponderance of support was found for those addressing the effects of both environmental and family-related characteristics on the cross-cultural adjustment of expatriates in firms with little international experience. Considerable support was also found for those hypotheses addressing the impact of organizational characteristics on the job satisfaction levels of expatriates assigned to mature subsidiaries. The relevant literatures on organizational learning and expatriation are reviewed, and a model is developed underlying the logic of the hypotheses. Research methods are then described in full detail, results are reported, and implications for theory and for management are discussed. ^
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Statement of the problem. It seeks to examine whether structural adjustment in Jamaica produced the desired developmental effects for labor--both organized and non-unionized--and if there is any significant difference in the Dominican Republic, which did not undergo that economic transformation. The research hypothesis is; "Structural Adjustment leads to Marginalization of labor."^ Methodology used. The methodology is mostly a straight cross-sectional analysis using data sets and publications from the UN, ILO, World Bank and IDB, as well as local statistical sources. The dissertation is primarily an historical to contemporary analysis of the Jamaican experience under structural adjustment, as it related to labor. To a greater extent it involves a straight cross-national comparison on the historical experiences of each country and a discussion of the relative similarities and differences between them, and the impact these features had on labor.^ Summary of findings. In the end, the question is asked as to whether internal factors are important in the relative success or failure of development strategies. From the data there is some indication that under structural adjustment there has been limited economic benefits for labor in Jamaica while labor standards have not improved. In the Dominican Republic the economic performance has been similar but the labor standards have improved significantly. This thus leads to the conclusion that structural adjustment may have been a factor in the resistance to labor's empowerment.^ Nevertheless, the study also shows that there may have been a causal role which local power relations had. The suggestion from the study is that in analyzing the phenomenon, attention must be paid to internal as well as external dynamics and variables. ^
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Since the late 1970's, but particularly since the mid-1980s, the economy of Nicaragua has had persistent and large macroeconomic imbalances, while GDP per-capita has declined to 1950s' levels. By the second half of the 1990s, huge fiscal deficits and a reduction of foreign financing resulted in record hyperinflation. The Sandinista government's (1979–1990) harsh stabilization program in 1988–89 had only modest and short-lived success. It was doomed by their inability to lower the public sector deficit due to the war, plus diminishing financial support from abroad. Hyperinflation stopped only after their 1990 electoral defeat ended the war and massive aid began to flow in. Five years later, macroeconomic stability is still very fragile. A sluggish recovery of export agriculture plus import liberalization, have impeded a reduction of huge trade and current account deficits. Facing the prospects of diminished aid flows, the government's strategy has hinged on the achievement of a real devaluation through a crawling-peg adjustment of the nominal rate. However, at the end of 1995 the situation of the external accounts was still critical, and the modest progress achieved was attributable to cyclical terms-of-trade improvement and changes in the political outlook of agricultural producers. Using a Computable General Equilibrium Model and a Social Accounting Matrix constructed for this dissertation, the importance of structural rigidities in production and demand in explaining such outcome is shown. It is shown that under the plausible structural assumptions incorporated in the model, the role of devaluation in the adjustment process is restricted by structural rigidities. Moreover, contrary to the premise of the orthodox economic thinking behind the economic program, it is the contractionary effect of devaluation more than its expenditure-switching effects that provide the basis for is use in solving the external sector's problems. A fixed nominal exchange rate is found to lead to adverse results. The broader conclusion that emerges from the study is that a new social compact and a rapid increase in infrastructure spending plus fiscal support for the traditional agro-export activities is at the center of a successful adjustment towards external viability in Nicaragua. ^
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The role of support from teachers on the academic and emotional adjustment of a ethnically and economically diverse sample of adolescents was examined. Analyses were conducted on data from a larger study examining social networks across the transition to junior high school. Participants in the current study included 694 African-American, Hispanic-American and European-American students in grades 6 and 8 from public elementary schools in South Florida. Some of these schools are located in economically distressed areas and some are in middle income areas. Children were interviewed, and information on teacher social support resources, school stressors, risk and academic and emotional adjustment was obtained. Several significant findings emerged from the analyses. First, overall teacher support was a significant predictor of a wide range of academic and emotional adjustment outcomes. Second, teacher support compensated for low peer support on teacher rated behavior problems. Third, teacher support interacted with school stress to predict depressed affect and self esteem. Fourth, teacher support interacted with low ecological risk conditions to predict feelings of loneliness. ^
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Points of transition, when major life roles undergo change, tend to be associated with an increased need for social support. The transition from adolescence to adulthood is ideal for the examination of the effect of normative stress on the development and functioning of social networks. A questionnaire was designed based on the convoy model to assess the influence of personal and situational characteristics on the utilization of support in the prediction of post-transition adjustment. Data were initially collected for a multi-ethnic sample of 741 sophomores and seniors in high school. Surveys were mailed to participants two years later, and one again the following year. The current study is based on data for 310 participants with complete data for all three time periods. A series of hierarchical regressions were conducted to compare three explanatory models of support: main effect, mediation, and moderation. A main effect model of support on post-transition adjustment was confirmed, a mediator model was not confirmed, and a moderator model was marginally confirmed. Family and friend support was related to significantly lower levels of loneliness, particularly for those with less adaptable temperaments. ^