944 resultados para strengthened
Resumo:
The significant social changes and unstable social–economic processes we are undergoing require more participation and more future oriented grassroots activity both in designing the possible future alternatives and in the actions for the realization of them. Action oriented futures studies and participatory futures studies are in close connection, because orientation towards actions and participation of non-professionals can be strengthened by their mutual interdependence in futures work. This study gives—as examples—summaries of four Hungarian case studies using participatory futures methods: one case from the field of vocational training, two cases concerning regional development, and one about national social–economic development. Our experience shows that such selected groups have evaluated the present issues in their environments as well as the closer and broader regional issues in authentic ways. The future alternatives that were outlined regarding the future of vocational training, acceptable future alternatives of domestic social–economic development, and future living conditions of a smaller settlement and in a larger town, reflected obligation, responsibility and personal interest. That non-professionals lack sufficient future orientation, and do not see possibilities to take serious actions for the future is a read problem. Fortunately, it seems that the future and action oriented attitude of the individuals might be further developed by the use of partnership education.
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A Pécsi Tudományegyetem Közgazdaságtudományi Karán sok éve folyó HR-kutatás legújabb eredménye ez a beszámoló, amely 74 Magyarországon is működő multinacionális vállalat helyi leányvállalatának HR-gyakorlatát vizsgálja. Az adatfelvétel (többségében helyszíni interjú) ideje 2010. április-november. Így a megállapítások már a válságból való kilábalás időszakára is vonatkoznak: mit és hogyan tettek a HR-szervezetek, valamint a vonalbeli vezetők a HR-munka hatékonyságának növelésére. A felállított 5, ezzel kapcsolatos hipotézist a szerzők vizsgálataik alapján részben igazolni tudták. A fő megállapítás: a nemzetközi vállalatok – minimális létszámcsökkentéssel – kitartottak Magyarország mellett, megerősítették a helyi leányvállalatoknál folyó HR-munkát. A kutatás nemzetközi keretekben jelenleg is folytatódik: 6 országban készülnek tanulmányok a helyi hasonló vállalati körre, a magyarországiéval azonos HR-vizsgálati szempontok alapján. _________ This article is the result of the several year long HR-research conducted at the Faculty of Business and Management of the University of Pécs, and it analyzes the HR-practices of the Hungarian subsidiaries of 74 multinational enterprises. Data collection (mostly interviews at the subsidiaries) took place during the period of April-November 2010. Hence, the findings also relate to the period of the recovery from the recession: what and how the HR-units/ and line managers did to increase the efficiency of the HR work. The 5 hypotheses in relation with this, could partially be verified by the research of the authors of this paper. The main finding is that the multinational enterprises – with a slight decrease of headcount – stood beside Hungary and strengthened the HR-activities at their subsidiaries. Research is still being continued internationally: studies are being prepared in 6 countries on similar groups of local companies, by using the same HR-research aspects as those used in Hungary.
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A sportszervezetek, sportvállalkozások esetében is kulcsfontosságú a teljesítménymérés. Annak ellenére, hogy a teljesítménymérés sok esetben elsősorban a sportteljesítményre koncentrál, egyre többen foglalkoznak az üzleti teljesítménymérés relevanciájával is. A nyugati társadalmakban a szűkös erőforrások és a növekvő társadalmi kontroll igénye erősíti ezt a folyamatot. A szakirodalom ezen a téren még viszonylag szűk körű. Jelen tanulmány célja, hogy egy olyan szakirodalmi áttekintést adjon, ami elindíthatja a jelenlegi és potenciális jövőbeli vezetők gondolkodását az üzleti teljesítménymérés fontosságának irányába. A tanulmány először áttekinti a pénzügyi teljesítménymérés lehetőségeit, foglalkozik a költségfelosztás problémakörével, kiemelt szerepet szán a stratégiai gondolkodás és a több szempontú megközelítés érvényesítésének. Részletesen összehasonlítja a sportszervezeteknél javasolt kiegyensúlyozott stratégiai mutatószámrendszer (BSC) adaptációkat. A tanulmány kiinduló pontot jelenthet nemcsak a szakirodalom feldolgozásához, de a gyakorlati megvalósításhoz is. _____ Performance measurement is crucial in sports associations. Although sports performance is in the spotlight, more and more researchers and experts deal with the business perspective of performance evaluation. This trend is strengthened by the scarcity of resources and a rising demand for social control in Western societies. The literature in this field is relatively limited. The aim of this study is to provide a literature review, which can motivate experts and managers to shift towards business thinking, and realize the importance of business performance evaluation. The study presents the opportunities of financial performance measurement, deals with the issues of cost allocation, and focuses on the role of strategic thinking and multi-dimension approach. Finally it compares the proposed balanced scorecard adaptations for sports associations. The study can be a starting point for literature review as well as for practical implementation.
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Science professional development, which is fundamental to science education improvement, has been described as being weak and fragmentary. The purpose of this study was to investigate teachers' perceptions of informal science professional development to gain an in-depth understanding of the essence of the phenomenon and related science-teaching dispositions. Based on the frameworks of phenomenology, constructivism, and adult learning theory, the focus was on understanding how the phenomenon was experienced within the context of teachers' everyday world. ^ Data were collected from eight middle-school teachers purposefully selected because they had participated in informal programs during Project TRIPS (Teaching Revitalized Through Informal Programs in Science), a collaboration between the Miami-Dade school district, government agencies (including NASA), and non-profit organizations (including Audubon of Florida). In addition, the teachers experienced hands-on labs offered through universities (including the University of Arizona), field sites, and other agencies. ^ The study employed Seidman's (1991) three-interview series to collect the data. Several methods were used to enhance the credibility of the research, including using triangulation of the data. The interviews were transcribed, color-coded and organized into six themes that emerged from the data. The themes included: (a) internalized content knowledge, (b) correlated hands-on activities, (c) enhanced science-teaching disposition, (d) networking/camaraderie, (e) change of context, and (f) acknowledgment as professionals. The teachers identified supportive elements and constraints related to each theme. ^ The results indicated that informal programs offering experiential learning opportunities strengthened understanding of content knowledge. Teachers implemented hands-on activities that were explicitly correlated to their curriculum. Programs that were conducted in a relaxed context enhanced teachers' science-teaching dispositions. However, a lack of financial and administrative support, perceived safety risks, insufficient reflection time, and unclear itineraries impeded program implementation. The results illustrated how informal educators can use this cohesive model as they develop programs that address the supports and constraints to teachers' science instruction needs. This, in turn, can aid teachers as they strive to provide effective science instruction to students; notions embedded in reforms. Ultimately, this can affect how learners develop the ability to make informed science decisions that impact the quality of life on a global scale. ^
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This study explores women's perceptions of what made them successful doctoral students and what strategies they used to cope and succeed in the academic environment of an off-campus program in South Florida. The study's theoretical framework was built on Bandura's (1997) theory regarding ways self-efficacy influences choices made and effort expended; and Gilligan (1982), Belenky et al. (1986) and other feminists' theories concerning how women learn. ^ The study included data obtained from individual, semi-structured interviews with 10 participants, documents spanning the 10 years of the program and interviews with founding faculty members. For each, academic resilience was built on (a) viewing that working on the degree was personally fulfilling; (b) believing she possessed a strong sense of academic confidence; (c) priding herself on having self discipline; (d) seeing herself as a role model; and (e) being motivated by a personal or career goal. ^ Strategies the participants used to overcome roadblocks included (a) time management—finding time for personal, professional, and academic duties; (b) focus—making the dissertation a priority; (c) collaboration—utilizing both personal and programmatic assistance; (d) and advocacy—acting on their individual needs. ^ Results of the study indicated that the program at the satellite campus provided structural resources that satisfied basic needs and strengthened the students' self-efficacy. This helped them become successful doctoral graduates. The women had personal fortitude and strong self-efficacy to complete the doctoral journey. They understood that their success was primarily based on the support they received from people: families, peers, and their major professors. Participants suggested that successful women students ascertain whether they have time and resources to devote to an extended study, an understanding family, and the resilience to overcome roadblocks along the way. ^
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The purpose of my dissertation was to examine the competition between the U.S.-led Western bloc and the Soviet bloc in the less developed world during Détente. I assessed whether or not the Soviet bloc pushed for strategic gains in the less developed world in the middle-to-late 1970's and whether this contributed to the U.S. decision to abandon Détente in 1979. I made the attempt to test the international relations theory of balance of threat realism (Walt, 1992). I accomplished the test in two ways. First, I measured the foreign aid allocations (military and economic) made by each respective bloc towards the Third World by using a quantitative approach. Second, I examined U.S. archives using the process-tracing/historical method. The U.S. archives gave me the ability to evaluate how U.S. decision-makers and U.S. intelligence agencies interpreted the actions of the Soviet bloc. They also gave me the chance to examine the U.S. response as we evaluated the policies that were pushed by key U.S. decision-makers and intelligence agencies. On the question of whether or not the Soviet bloc was aggressive, the quantitative evidence suggested that it was not. Instead, the evidence found the Western-bloc to have been more aggressive in the less developed world. The U.S. archives also showed Soviet actions to have been defensive. Key U.S. decision-makers and intelligence agencies attested to this. Finally, the archives show that U.S. officials pushed for aggressive actions against the Third World during the final years of Détente. Thus, balance of threat realism produced an incorrect assessment that U.S. aggression in the late 1970's was a response to Soviet aggression during Détente. The evidence suggests structural Marxism and domestic politics can better explain U.S./Western actions. The aggressive foreign aid allocations of the West, coupled with evidence of U.S. decision-makers/agencies vehemently concerned about the long-term prospects of the West, strengthened structural Marxism. Domestic politics can also claim to explain the actions of U.S. decision-makers. I found extensive archival evidence of bureaucratic inter-agency conflict between the State Department and other intelligence agencies in areas of strategic concern to the U.S.
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The National Center for Family Literacy (2003a) and the National Even Start Association (2005) have stated that the single most effective and influential factor in increasing student academic achievement is parental involvement. The purpose of this qualitative study was to determine how participation in adult literacy courses influences parent-child interaction in various educationally related activities known as Interactive Literacy Activities (ILAs). This study investigated ILAs from the mothers? perspective, and examines the changes that occur in parental involvement or ILAs when immigrant parents of a limited educational background participate in an adult education program. The principal method of data collection was key informant interviews (Gall, Borg, & Gall, 1996). Other methods of data collection included observations of parent-child interactions and field observations. Data analysis methods included Memo-ing (Miles & Huberman, 1994), within case analysis and cross-case analysis. ^ Findings demonstrate that changes occurred in the parent-child relationship when mothers of a limited educational background participated in an adult literacy course. When participating in ILAs or English literacy activities related to second language acquisition (including reading and speaking for comprehension and pronunciation), the children of these mothers took on the role of the adult. Participation in literacy activities was often initiated by the child and the children were frequently concerned with their mother's literacy acquisition. Mothers reported that their children were more confident, worked harder on school related activities and were more open to communication. ^ It can be concluded from this study that, in the case of these immigrant families, a mother's participation in adult literacy classes is influential in the relationship between mother and child. These children participated in ILAs for the benefit of their mothers and initiated literacy activities more frequently. The children responded better to their parents during literacy activities because there was a positive change in the relationship between mother and child. The relationship between mother and child appeared to be strengthened by greater trust, a sense of pride and more communication. ^
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This study examines the impact of globalization and religious nationalism on the personal and professional lives of urban Hindu middle class media women. The research demonstrates how newly strengthened forces of globalization and Hindutva shape Indian womanhood. The research rests on various data that reveal how Indian women interpret and negotiate constructed identities. The study seeks to give voice to the objectified by scrutinizing and challenging the stereotypical modern faces of Indian womanhood seen in the narratives of globalization and Hindutva. Feminist open-ended interviewing was conducted in English and Hindi in New Delhi, the capital of India, with 23 Hindu women, employed by electronic and print media corporations. Accumulated data were analyzed and interpreted using feminist critical discourse analysis. Findings from the study indicate that while the Indian middle class women have embraced professional opportunities presented by globalization, they remain circumscribed by mutating gender politics. The research also finds that as academic and professional progress empower the women within their homes, their public lives have become fraught with increasing gender violence and decreasing recourse to justice. Therefore, women accept the power stratification of their lives as being dependent on spatial and temporal distinctions, and have learnt to engage and strategize with the public environment for physical safety and personal-professional progress. While the media women see systemic masculine domination as being symbiotic with tenets of religious nationalism, they exhibit an unquestioned embracing of capitalism/globalization as the means of empowerment. My research also strongly indicates the importance of the media’s role in shaping gender dynamics in a global context. In conclusion, my research shows the mediawomen’s immense agency in pursuing academic and professional careers while being aware of deeply ingrained gender roles through their strong commitment towards their families. The findings of this study contribute to the literature on Third World nationalism, urban globalization and understandings of reworked-renewed masculine domination. Finally, the study also engages with recent scholarship on the Indian middle class (See Nanda 2010; Shenoy 2009; Lukose 2005; and Radhakrishnan 2006) while simultaneously addressing the notions of privilege and disengagement levied at the middle class woman, a symbiosis of idealization and imprisonment.
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A difficult transition to a new paradigm of Democratic Security and the subsequent process of military restructuring during the nineties led El Salvador, Honduras, Guatemala and Nicaragua to re-consider their old structures and functions of their armed forces and police agencies. This study compares the institutions in the four countries mentioned above to assess their current condition and response capacity in view of the contemporary security challenges in Central America. This report reveals that the original intention of limiting armies to defend and protect borders has been threatened by the increasing participation of armies in public security. While the strength of armies has been consolidated in terms of numbers, air and naval forces have failed to become strengthened or sufficiently developed to effectively combat organized crime and drug trafficking and are barely able to conduct air and sea operations. Honduras has been the only country that has maintained a proportional distribution of its armed forces. However, security has been in the hands of a Judicial Police, supervised by the Public Ministry. The Honduran Judicial Police has been limited to exercising preventive police duties, prohibited from carrying out criminal investigations. Nicaragua, meanwhile, possesses a successful police force, socially recognized for maintaining satisfactory levels of security surpassing the Guatemalan and El Salvadoran police, which have not achieved similar results despite of having set up a civilian police force separate from the military. El Salvador meanwhile, has excelled in promoting a Police Academy and career professional education, even while not having military attachés in other countries. Regarding budgetary issues, the four countries allocate almost twice the amount of funding on their security budgets in comparison to what is allocated to their defense budgets. However, spending in both areas is low when taking into account each country's GDP as well as their high crime rates. Regional security challenges must be accompanied by a professionalization of the regional armies focused on protecting and defending borders. Therefore, strong institutional frameworks to support the fight against crime and drug trafficking are required. It will require the strengthening of customs, greater control of illicit arms trafficking, investment in education initiatives, creating employment opportunities and facilitating significant improvements in the judicial system, as well as its accessibility to the average citizen.
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Despite historical tensions between the Dominican Republic and Haiti, Dominicans appear to have put aside their resentment in favor of supporting Haitians after the earthquake that devastated the neighbor nation in January 2010. Over the past several months, there has been unprecedented cooperation between the Dominican Republic and Haiti, with little evidence of a negative impact on domestic politics in the Dominican Republic. In fact, the high ratings of President Leonel Fernández and the results of the May Parliamentary elections may suggest that how the Fernández administration handled the Haitian crisis did not have a negative impact on citizens’ perception. However, the issue of Haitian immigration remains very sensitive in the Dominican Republic, and has the potential to become the major concern on the domestic political front. As of June 2010, the Haitian crisis seemed to have little or no impact on Dominican politics, as the following points indicate: The May 16, 2010 Parliamentary elections increased President Fernández political party to 31 out of 32 Senate seats, and 105 out of 183 Chamber of Deputies seats; this is a total increase of 18 seats from the previous term. Polls indicate that President Fernández has a 54 percent approval rating. Polls also indicate that Haiti is not among the most pressing issues of concern to Dominican citizens. Instead, 65 percent of the population identifies drug trafficking and corruption as the greatest concerns. The immigration debate will remain the major consideration in domestic politics in the Dominican Republic; 62.4 percent of Dominicans polled think that the military should be strengthened along the DR-Haitian border.
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This study examines the influence of acculturative stress on substance use and HIV risk behaviors among recent Latino immigrants. The central hypothesis of the study is that specific religious coping mechanisms influence the relationship that acculturative stress has on the substance use and HIV-risk behaviors of recent Latino immigrants. Within the Latino culture religiosity is a pervasive force, guiding attitudes, behaviors, and even social interactions. When controlling for education and socioeconomic status, Latinos have been found to use religious coping mechanisms more frequently than their Non-Latino White counterparts. In addition, less acculturated Latinos use religious coping strategies more frequently than those with higher levels of acculturation. Given its prominent role in Latino culture, it appears probable that this mechanism may prove to be influential during difficult life transitions, such as those experienced during the immigration process. This study examines the moderating influence of specific religious coping mechanisms on the relationship between acculturative stress and substance use/HIV risk behaviors of recent Latino immigrants. Analyses for the present study were conducted with wave 2 data from an ongoing longitudinal study investigating associations between pre-immigration factors and health behavior trajectories of recent Latino immigrants. Structural equation and zero-inflated Poisson modeling were implemented to test the specified models and examine the nature of the relationship among the variables. Moderating effects were found for negative religious coping. Higher levels of negative religious coping strengthened an inverse relationship between acculturative stress and substance use. Results also indicated direct relationships between religious coping mechanisms and substance use. External and positive religious coping were inversely related to substance use. Negative religious coping was positively related to substance use. This study aims to contribute knowledge of how religious coping influence's the adaptation process of recent Latino immigrants. Expanding scientific understanding as to the function and effect of these coping mechanisms could lead to enhanced culturally relevant approaches in service delivery among Latino populations. Furthermore this knowledge could inform research about specific cognitions and behaviors that need to be targeted in prevention and treatment programs with this population.
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Colombia's increasingly effective efforts to mitigate the power of the FARC and other illegitimately armed groups in the country can offer important lessons for the Peruvian government as it strives to prevent a resurgence of Sendero Luminoso and other illegal non-state actors. Both countries share certain particular challenges: deep economic, social, and in the case of Peru ethnic divisions, the presence of and/or the effects of violent insurgencies, a large-scale narcotics production and trafficking, and a history of weak state presence in large tracts of isolated and scarcely-populated areas. Important differences exist, however in the nature of the insurgencies in the two countries, the government response to them and the nature of government and society that affects the applicability of Colombia's experience to Peru. The security threat to Panama from drug trafficking and Colombian insurgents --often a linked phenomenon-- are in many ways different from the drug/insurgent factor in Colombia itself and in Peru, although there are similar variables. Unlike the Colombian and Peruvian cases, the security threat in Panama is not directed against the state, there are no domestic elements seeking to overthrow the government -- as the case of the FARC and Sendero Luminoso, security problems have not spilled over from rural to urban areas in Panama, and there is no ideological component at play in driving the threat. Nor is drug cultivation a major factor in Panama as it is in Colombia and Peru. The key variable that is shared among all three cases is the threat of extra-state actors controlling remote rural areas or small towns where state presence is minimal. The central lesson learned from Colombia is the need to define and then address the key problem of a "sovereignity gap," lack of legitimate state presence in many part of the country. Colombia's success in broadening the presence of the national government between 2002 and the presence is owed to many factors, including an effective national strategy, improvements in the armed forces and police, political will on the part of government for a sustained effort, citizen buy-in to the national strategy, including the resolve of the elite to pay more in taxes to bring change about, and the adoption of a sequenced approach to consolidated development in conflicted areas. Control of territory and effective state presence improved citizen security, strengthened confidence in democracy and the legitimate state, promoted economic development, and helped mitigate the effect of illegal drugs. Peru can benefit from the Colombian experience especially in terms of the importance of legitimate state authority, improved institutions, gaining the support of local citizens, and furthering development to wean communities away from drugs. State coordinated "integration" efforts in Peru as practiced in Colombia have the potential for success if properly calibrated to Peruvian reality, coordinated within government, and provided with sufficient resources. Peru's traditionally weak political institutions and lack of public confidence in the state in many areas of the country must be overcome if this effort is to be successful.
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Secrecy is fundamental to computer security, but real systems often cannot avoid leaking some secret information. For this reason, the past decade has seen growing interest in quantitative theories of information flow that allow us to quantify the information being leaked. Within these theories, the system is modeled as an information-theoretic channel that specifies the probability of each output, given each input. Given a prior distribution on those inputs, entropy-like measures quantify the amount of information leakage caused by the channel. ^ This thesis presents new results in the theory of min-entropy leakage. First, we study the perspective of secrecy as a resource that is gradually consumed by a system. We explore this intuition through various models of min-entropy consumption. Next, we consider several composition operators that allow smaller systems to be combined into larger systems, and explore the extent to which the leakage of a combined system is constrained by the leakage of its constituents. Most significantly, we prove upper bounds on the leakage of a cascade of two channels, where the output of the first channel is used as input to the second. In addition, we show how to decompose a channel into a cascade of channels. ^ We also establish fundamental new results about the recently-proposed g-leakage family of measures. These results further highlight the significance of channel cascading. We prove that whenever channel A is composition refined by channel B, that is, whenever A is the cascade of B and R for some channel R, the leakage of A never exceeds that of B, regardless of the prior distribution or leakage measure (Shannon leakage, guessing entropy leakage, min-entropy leakage, or g-leakage). Moreover, we show that composition refinement is a partial order if we quotient away channel structure that is redundant with respect to leakage alone. These results are strengthened by the proof that composition refinement is the only way for one channel to never leak more than another with respect to g-leakage. Therefore, composition refinement robustly answers the question of when a channel is always at least as secure as another from a leakage point of view.^
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The terrigenous sediment proportion of the deep sea sediments from off Northwest Africa has been studied in order to distinguish between the aeolian and the fluvial sediment supply. The present and fossil Saharan dust trajectories were recognized from the distribution patterns of the aeolian sediment. The following timeslices have been investigated: Present, 6,000, 12,000 and 18,000 y. B. P. Furthermore, the quantity of dust deposited off the Saharan coast has been estimated. For this purpose, 80 surface sediment samples and 34 sediment cores have been analysed. The stratigraphy of the cores has been achieved from oxygen isotopic curves, 14C-dating, foraminiferal transfer temperatures, and carbonate contents. Silt sized biogenic opal generally accounts for less than 2 % of the total insoluble sediment proportion. Only under productive upwelling waters and off river mouths, the opal proportion exceeds 2 % significantly. The modern terrigenous sediment from off the Saharan coast is generally characterized by intensely stained quartz grains. They indicate an origin from southern Saharan and Sahelian laterites, and a zonal aeolian transport in midtropospheric levels, between 1.5 an 5.5 km, by 'Harmattan' Winds. The dust particles follow large outbreaks of Saharan air across the African coast between 15° and 21° N. Their trajectories are centered at about 18° N and continue further into a clockwise gyre situated south of the Canary Islands. This course is indicated by a sickle-shaped tongue of coarser grain sizes in the deep-sea sediment. Such loess-sized terrigenous particles only settle within a zone extending to 700 km offshore. Fine silt and clay sized particles, with grain sizes smaller than 10- 15 µm, drift still further west and can be traced up to more than 4,000 km distance from their source areas. Additional terrigenous silt which is poor in stained quartz occurs within a narrow zone off the western Sahara between 20° and 27° N only. It depicts the present dust supply by the trade winds close to the surface. The dust load originates from the northwestern Sahara, the Atlas Mountains and coastal areas, which contain a particularly low amount of stained quartz. The distribution pattern of these pale quartz sediments reveals a SSW-dispersal of dust being consistent with the present trade wind direction from the NNE. In comparison to the sediments from off the Sahara and the deeper subtropical Atlantic, the sediments off river mouths, in particular off the Senegal river, are characterized by an additional input of fine grained terrigenous particles (< 6 µm). This is due to fluvial suspension load. The fluvial discharge leads to a relative excess of fine grained particles and is observed in a correlation diagram of the modal grain sizes of terrigenous silt with the proportion of fine fraction (< 6 µm). The aeolian sediment contribution by the Harmattan Winds strongly decreased during the Climatic Optimum at 6,000 y. B. P. The dust discharge of the trade winds is hardly detectable in the deep-sea sediments. This probably indicates a weakened atmospheric circulation. In contrast, the fluvial sediment supply reached a maximum, and can be traced to beyond Cape Blanc. Thus, the Saharan climate was more humid at 6,000 y B. P. A latitudinal shift of the Harmattan driven dust outbreaks cannot be observed. Also during the Glacial, 18,000 y. B. P., Harmattan dust transport crossed the African coast at latitudes of 15°-20° N. Its sediment load increased intensively, and markedly coarser grains spread further into the Atlantic Ocean. An expanded zone of pale-quart sediments indicates an enhanced dust supply by the trade winds blowing from the NE. No synglacial fluvial sediment contribution can be recognized between 12° and 30° N. This indicates a dry glacial climate and a strengthened stmospheric circulation over the Sahelian and Saharan region. The climatic transition pahes, at 12, 000 y. B. P., between the last Glacial and the Intergalcial, which is compareable to the Alerod in Europe, is characterized by an intermediate supply of terrigenous particles. The Harmattan dust transport wa weaker than during the Glacial. The northeasterly trade winds were still intensive. River supply reached a first postglacial maximum seaward of the Senegal river mouth. This indicates increasing humidity over the southern Sahara and a weaker atmospheric circulation as compared to the glacial. The accumulation rates of the terrigenous silt proportion (> 6 µm) decrcase exponentially with increasing distance from the Saharan coast. Those of the terrigenous fine fraction (< 6 µm) follow the same trend and show almost similar gradients. Accordingly, also the terrigenous fine fraction is believed to result predominantly from aeolian transport. In the Atlantic deep-sea sediments, the annual terrigenous sediment accumulation has fluctuated, from about 60 million tons p. a. during the Late Glacial (13,500-18,000 y. B. P, aeolian supply only) to about 33 million tons p. a. during the Holocene Climatic Optimum (6,000-9,000 y. B. P, mainly fluvial supply), when the river supply has reached a maximum, and to about 45 million tons p. a. during the last 4,000 years B. P. (fluvial supply only south of 18° N).
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The past variability of the South Asian Monsoon is mostly known from records of wind strength over the Arabian Sea while high-resolution paleorecords from regions of strong monsoon precipitation are still lacking. Here, we present records of past monsoon variability obtained from sediment core SK 168/GC-1, which was collected at the Alcock Seamount complex in the Andaman Sea. We utilize the ecological habitats of different planktic foraminiferal species to reconstruct freshwater-induced stratification based on paired Mg/Ca and d18O analyses and to estimate seawater d18O (d18Osw). The difference between surface and thermocline temperatures (delta T) and d18Osw (delta d18Osw) is used to investigate changes in upper ocean stratification. Additionally, Ba/Ca in G. sacculifer tests is used as a direct proxy for riverine runoff and sea surface salinity (SSS) changes related to monsoon precipitation on land. Our delta d18Osw time series reveals that upper ocean salinity stratification did not change significantly throughout the last glacial suggesting little influence of NH insolation changes. The strongest increase in temperature gradients between the mixed layer and the thermocline is recorded for the mid-Holocene and indicate the presence of a significantly shallower thermocline. In line with previous work, the d18Osw and Ba/Ca records demonstrate that monsoon climate during the LGM was characterized by a significantly weaker southwest monsoon circulation and strongly reduced runoff. Based on our data the South Asian Summer Monsoon (SAM) over the Irrawaddyy strengthened gradually after the LGM beginning at ~18 ka. This is some 3 kyrs before an increase of the Ba/Ca record from the Arabian Sea and indicates that South Asian Monsoon climate dynamics are more complex than the simple N-S displacement of the ITCZ as generally described for other regions. Minimum d18Osw values recorded during the mid-Holocene are in phase with Ba/Ca marking a stronger monsoon precipitation, which is consistent with model simulations.