Language and migration : the impact of the Jukun on Chadic speaking groups in the Benue-Gongola basin

Our paper deals with the problems of migration, culture and language in the wider Benue-Gongola basin. Here are mainly concerned the West-Chadic speaking groups Kwami, Kupto, Kushi and Piya as well as the Jukun who speak a language belonging to the Benue-Congo family. We try to point out the possible reasons for their historical migrations and in particular the consequences of ethnic expansion of the Jukun in the middle Benue region. History shows that contacts of ethnic groups - being peaceful or by force - had always led to mutual influences and changes in culture and language, which finally resulted in cultural fusion of various aspects. Our study, based mainly on oral traditions as well as on linguistic comparisons, focusses especially on the history of the above mentioned Chadic groups, who are considered - according to our hypothesis - to have come in close contact with the Jukun. Subsequently the warlike expansion of the Jukun caused a strong turmoil which led to the scattering of the various ethnic units

Can Distribution Grids Significantly Contribute to Transmission Grids' Voltage Management?

Power generation in Germany is currently transitioning from a system based on large, central, thermal power plants to one that heavily relies on small, decentral, mostly renewable power generators. This development poses the question how transmission grids' reactive power demand for voltage management, covered by central power plants today, can be supplied in the future. In this work, we estimate the future technical potential of such an approach for the whole of Germany. For a 100% renewable electricity scenario we set the possible reactive power supply in comparison with the reactive power requirements that are needed to realize the simulated future transmission grid power flows. Since an exact calculation of distribution grids' reactive power potential is difficult due to the unavailability of detailed grid models on such scale, we optimistically estimate the potential by assuming a scaled, averaged distribution grid model connected to each of the transmission grid nodes. We find that for all except a few transmission grid nodes, the required reactive power can be fully supplied from the modeled distribution grids. This implies that - even if our estimate is overly optimistic - distributed reactive power provisioning will be a technical solution for many future reactive power challenges

Consistency of vitamin and/or mineral supplement use and demographic, lifestyle and health-status predictors: findings from the European Prospective Investigation into Cancer and Nutrition (EPIC)-Heidelberg cohort

Cross-sectional studies suggest that dietary supplement use is associated with favourable demographic and lifestyle factors and certain health conditions. However, factors that affect the consistency of supplement use have not been investigated in prospective cohort studies. The aim of the present study was to seek baseline demographic, lifestyle and health-status predictors of subsequent consistent vitamin and/or mineral supplement use. A total of 8968 men and 10672 women of the European Prospective Investigation into Cancer and Nutrition (EPIC)-Heidelberg cohort, who answered the supplement-use questions in the baseline survey and two follow-up surveys, were categorised into three groups: consistent, inconsistent and never users. At baseline, 28·5% of men and 38·6% of women reported vitamin and/or mineral supplement use. After a median follow-up of 8·5 years, 14·6% of men and 22·9% of women were consistent users. During follow-up, 36·0% of male and 26·6% of female initial users stopped supplement use, whereas 27·8% of male and 39·4% of female initial non-users started supplement use. Women were more likely to be consistent users than men. Older age (≥50 years), lower BMI (<25kg/m2) and self-reported hyperlipidaemia were common predictors of consistent use for both sexes. Additional predictors included higher educational level for men, and being more physically active and higher lifetime alcohol consumption for women. Consistent users had the highest intake of dairy products, fish, fruits and vegetables, and wine but the lowest intake of total meat. We concluded that supplement use is a fairly unstable behaviour in free-living individuals. Individuals with a favourable lifestyle and healthier diet are more likely to show consistent supplementatio

Dietary calcium and magnesium intake in relation to cancer incidence and mortality in a German prospective cohort (EPIC-Heidelberg)

To prospectively evaluate the associations of dietary calcium and magnesium intake with cancer incidence and mortality, data of 24,323 participants of the Heidelberg cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC-Heidelberg), who were aged 35-64years and cancer-free at recruitment (1994-1998), were analyzed using multivariate Cox regression models. After an average follow-up time of 11years, 2,050 incident cancers were diagnosed and 513 cancer deaths occurred. Dietary calcium intake was inversely but not statistically significantly associated with colorectal cancer risk (hazard ratio [HR] for per 100mg increase in intake: 0.95; 95% confidence interval [CI]: 0.88, 1.02) and lung cancer risk (HR for per 100mg increase in intake: 0.94; 95% CI: 0.87, 1.02). No statistically significant associations were observed between dietary calcium intake and site-specific or overall cancer incidence or mortality. Dietary magnesium intake was not statistically significantly associated with any of the investigated outcomes. This prospective cohort study provides no strong evidence to support that high dietary calcium and magnesium intake in the intake range observed in a German population may reduce cancer incidence or mortalit

Vitamin/mineral supplementation and cancer, cardiovascular, and all-cause mortality in a German prospective cohort (EPIC-Heidelberg)

Purpose: To prospectively evaluate the association of vitamin/mineral supplementation with cancer, cardiovascular, and all-cause mortality. Methods: In the Heidelberg cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC-Heidelberg), which was recruited in 1994-1998, 23,943 participants without pre-existing cancer and myocardial infarction/stroke at baseline were included in the analyses. Vitamin/mineral supplementation was assessed at baseline and during follow-up. Cox regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). Results: After an average follow-up time of 11years, 1,101 deaths were documented (cancer deaths=513 and cardiovascular deaths=264). After adjustment for potential confounders, neither any vitamin/mineral supplementation nor multivitamin supplementation at baseline was statistically significantly associated with cancer, cardiovascular, or all-cause mortality. However, baseline users of antioxidant vitamin supplements had a significantly reduced risk of cancer mortality (HR: 0.52; 95% CI: 0.28, 0.97) and all-cause mortality (HR: 0.58; 95% CI: 0.38, 0.88). In comparison with never users, baseline non-users who started taking vitamin/mineral supplements during follow-up had significantly increased risks of cancer mortality (HR: 1.74; 95% CI: 1.09, 2.77) and all-cause mortality (HR: 1.58; 95% CI: 1.17, 2.14). Conclusions: Based on limited numbers of users and cases, this cohort study suggests that supplementation of antioxidant vitamins might possibly reduce cancer and all-cause mortality. The significantly increased risks of cancer and all-cause mortality among baseline non-users who started taking supplements during follow-up may suggest a "sick-user effect,” which researchers should be cautious of in future observational studie

The Effects of Culture in Computer-Mediated Negotiations

The paper explores the impact of culture on anonymous inter- and intracultural negotiations conducted via the Internet using a Web-based negotiation support system (NSS). In e-negotiations, technology acts as a moderator in the relationship between culture and negotiation behavior. This implies that patterns of cultural impact on negotiations can be different from face-to-face negotiations. Communication technology reduces the transmission of social cues and increases the importance of explicit communication. Thus, cultural dimensions such as power distance, which rely on social cues, are reduced in their impact, while the impact of communication-related dimensions of cultures such as high vs. low context is amplified by the system. The empirical analysis of these effects is based on a set of bilateral negotiations involving 1366 participants carried out with the Web-based NSS Inspire. It indicates a significant influence of culture, particularly regarding negotiators’ expectations. We also found significant cultural differences with regard to communication patterns emerging during the negotiation process and outcomes of negotiations. Our results also indicate that as the negotiation process progresses, individual differences between negotiators, including their approach to problem solving, become more important than their cultural characteristics

Development and testing of the 3U+ CubeSat PCDU for SOURCE

SOURCE (Stuttgart Operated University CubeSat for Evaluation and Education) is a 3U+ re-search CubeSat that is being developed by students at the University of Stuttgart in coopera-tion with the Institute for Space Systems and the Small Satellite Student Society KSat e.V.. The objectives include technology demonstrations, atmospheric research and the investigation of satellite demise while also serving as an educational program. SOURCE was selected by ESA's "Fly your Satellite" program and is currently in Phase D. The electrical power supply system combines commercial off-the-shelf parts with self-devel-oped units to meet the requirements of the payloads. The solar array configuration and Power Conditioning and Distribution Unit (PCDU) are self-developed, while the battery is a commer-cial product. A total of 56 solar cells provides up to 32W under ideal conditions, which can be stored in a 75Wh space-qualified lithium-ion battery. To maximise the power output of the solar cells, maximum power point tracking is performed by the PCDU. This is controlled by a radiation hardened microcontroller. The PCDU provides regulated 3.3V, 5V and unregulated battery voltage to the subsystems with 32 switchable outputs, 27 of which are latch-up current protected. The microcontroller controls these individual output channels and the switching between the various CubeSat modes as commanded by the on-board computer. Additionally, every output channel power consumption is monitored for overcurrents. The PCDU functions as a watchdog by checking the health of the on-board computer, rebooting it in case of a failure. High priority commands can be sent directly to the PCDU from the ground via the communication system, bypassing the on-board computer. These can reset either the communication subsystem, the on-board computer or the entire satellite. Four hybrid inhibits, using a combination of mechanical switches and FETs are integrated in the PCDU, replacing the usual fully mechanical design. Three are used to deactivate the satellite in the deployer configuration and the fourth is a remove-before-flight inhibit. An engineering model was manufactured during phase C and is being tested functionally, en-vironmentally and for performance. This paper presents the detailed design of the PCDU, the acquired test results and outlines issues encountered during the test