386 research outputs found

    The Golden City on the Edge: Economic Geography and Jihad over Centuries

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    This paper uncovers the evolution of cities and Islamist insurgencies, so called jihad, in the process of the reversal of fortune over the centuries. In West Africa, water access in ancient periods predicts the locations of the core cities of inland trade routes -- the trans-Saharan caravan routes -- founded up to the 1800s, when historical Islamic states played significant economic roles before European colonization. In contrast, ancient water access does not have a persistent influence on contemporary city formation and economic activities. After European colonization and the invention of modern trading technologies, along with the constant shrinking of water sources, landlocked pre-colonial core cities contracted or became extinct. Employing an instrumental variable strategy, we show that these deserted locations have today been replaced by battlefields for jihadist organizations. We argue that the power relations between Islamic states and the European military during the 19th century colonial era shaped the persistence of jihadist ideology as a legacy of colonization. Investigations into religious ideology related to jihadism, using individual-level surveys from Muslims, support this mechanism. Moreover, the concentration of jihadist violence in "past-core-and-present-periphery" areas in West Africa is consistent with a global-scale phenomenon. Finally, spillovers of violent events beyond these stylized locations are partly explained by organizational heterogeneity among competing factions (Al Qaeda and the Islamic State) over time

    Effects of weather variability and air pollutants on emergency admissions for cardiovascular and cerebrovascular diseases.

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    This is an Author's Original Manuscript of an Article submitted for consideration in the International journal of environmental health research copyright (c) 2012 Taylor & Francis; International journal of environmental health research is available online at http://www.tandfonline.com/10.1080/09603123.2011.650155信州大学博士(医学)・学位論文・平成23年3月31日授与(甲第901号)・掘綾We examined the effect of ambient temperature, air pressure and air pollutants on daily emergency admissions by identifying the cause of admission for each type of stroke and cardiovascular disease using generalized linear Poisson regressionmodels allowing for overdispersion, and controlling for seasonal and inter-annual variations, days of the week and public holidays, levels of influenza and respiratory syncytial viruses. Every 1 degrees C decrease in mean temperature was associated with an increase in the daily number of emergency admissions by 7.83% (95% CI 2.06-13.25) for acute coronary syndrome (ACS) and heart failure, by 35.57% (95% CI 15.59-59.02) for intracerebral haemorrhage (ICH) and by 11.71% (95% CI 4.1-19.89) for cerebral infarction. An increase of emergency admissions due to ICH (3.25% (95% CI 0.94-5.51)), heart failure (3.56% (95% CI 1.09-5.96)) was observed at every 1 hPa decrease in air pressure from the previous days. We found stronger detrimental effect of cold on stroke than cardiovascular disease.Articlejournal articl

    Evaluation of effective period of a juvenile hormone mimic, pyriproxyfen, against Aedes albopictus : Preliminary experiments in the laboratory and the field.

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    Effective period of pyriproxyfen against Aedes albopictus was evaluated in the laboratory and the field. Experimental containers were treated with 3 different concentrations of pyriproxyfen and placed in the laboratory. In the field, the experimental containers were placed for 3 weeks, and then treated with the same concentrations as the laboratory experiment. Pupae were collected and the emergence of adults was examined every 2 weeks for 8 weeks. Pyriproxyfen was more effective in the laboratory than in the field. The change of water amount was one of the important factors determining the efficiency of pyriproxyfen in the field. No significant differences were observed in the number of collected pupae among concentrations in the laboratory, while smaller number of pupae were collected from the higher concentrations in the field. The duration for the complete inhibition of adult emergence at the highest concentration (0.1 ppm) was 4 and 6 weeks in the field and in the laboratory, respectively

    A Field Experiment of the Emergence Inhibition of a Juvenile Hormone Mimic, Pyriproxyfen, Against Aedes albopictus in Nagasaki, Japan

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    A field experiment was conducted to examine the duration of complete inhibition of adult emergence of Aedes albopictus at 3 different concentrations of pyriproxyfen (0.1, 1, and 10ppm). Forty plastic containers with 1,000ml of water were placed as ovi-traps at the campus of Nagasaki University School of Medicine on 1 June 1993. Twenty-five ovi-traps were treated with 0.1, 1, and 10ppm of pyriproxyfen and 15 ovi-traps were left without treatment as the control. Pupae of naturally breeding Ae. albopictus were collected from the ovi-traps 3 times a week from June to October and the percentage of adult emergence was examined in the laboratory. The emergence of adults was inhibited completely during the whole study period at the highest concentration of 10ppm, whereas the complete inhibition of emergence was never observed at the lowest concentration of 0.1ppm. The negative correlation between the concentration of pyriproxyfen and the density of puape was observed in the whole experimental period, except the late October. The minimum concentration of pyriproxyfen that results in the complete inhibition of adult emergence of Ae. albopictus during the whole breeding season was estimated around 1ppm in the field conditions in Nagasaki

    A Comparative Study on Life Table Characteristics of Two Strains of Aedes albopictus from Japan and Thailand

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    Life tables of two strains of Aedes albopictus originated from Nagasaki, Japan and Chiangmai, Thailand were examined in the laboratory conditions of 27℃, 75% R.H. and 16L:8D. The developmental period (egg to adult) in females of Chiangmai strain tended to be shorter than in those of Nagasaki strain. The body sizes of femals were not significantly different between the two strains. Since females of Nagasaki strain took blood meals more frequently and produced more eggs per blood meal than those of Chiangmai strain, a marked difference was observed in m_x-curve between the two strains. l_x-curve of females in the two strains were similar and no significant differences were observed in the longevity of the females. Nagasaki strain showed larger values of the net reproductive rate and the intrinsic rate of increase, and longer mean generation time than Chiangmai strain

    Seasonal Occurrence of Aedes aegypti and Ae. albopictus in Used Tires in 1992-1994, Chiangmai, Thailand

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    Mosquito larvae breeding in 47 used tires were collected weekly by a siphon from July, 1992 to August, 1994 at Office of Vector Borne Disease Control (former Malaria Center), Region 2, Chiangmai, Thailand. Acidity, chemical oxygen demand (COD), and concentrations of NH_4 and NO_2 were also measured every 3 weeks in the field for each tire. The number of tires with Ae. albopictus was always larger than that with Ae. aegypti. Both in 1992 and 1993 the decrease in the number of tires with Ae. aegypti was observed earlier than that of Ae. albopictus. The number of tires with Ae. aegypti decreased in the latter half of the rainy season, while that with Ae. albopictus decreased in the dry season. Significant temporal variations were observed in pH, COD and NH_4. However all the changes did not correlate with the population decline of Ae. aegypti during the latter half of the rainy season. The coefficient of association (C_8) between Ae. aegypti and Ae. albopictus was positive and statistically significant

    Tempo-spatial variation in feeding activity and density of Aedes albopictus (Diptera: Culicidae) at peridomestic habitat in Nagasaki, Japan.

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    金沢大学理工研究域 自然システム学系1998年9月, 長崎大学熱帯医学研究所敷地内で家屋周辺の茂み及び裸地においてヒトスジシマカの24時間採集を行い, 周辺環境の異なる採集場所における吸血活動性と密度のちがいを調べた。ヒトスジシマカの密度は茂みで高く, 屋内や裸地で低かった。吸血活動は薄明薄暮に高まり, 夜も高かった。最も活動性が高い薄暮には, 統計的な有意差はみられないが, 昼間や夜間に比べて屋内や裸地で採集される雌個体の割合が高かった。以上の結果からヒトスジシマカの生態における夜間の吸血活動の重要性と薄明薄暮には茂み以外に裸地や屋内などでも吸血される機会が増加することが示唆された。 To clarify the tempo-spatial variation in feeding of Aedes albopictus, a field investigation was conducted in a field where the species heavily infested, in Nagasaki. Feeding activity was observed in the nighttime as well as at dawn and dusk. The density was high at sites with vegetation and low at sites without vegetation and indoors. At sites with vegetation, the proportion of females decreased at dawn and dusk, while it increased at sites without vegetation and indoors. Feeding activity in nighttime is possibly common in Ae. albopictus, and the place of feeding expands from sites with vegetation to sites without vegetation and indoors at dawn and dusk

    Preliminary Field Experiments on the Oviposition of Aedes albopictus in Water with Different Qualities

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    Oviposition preference of Aedes albopictus was examined by placing ovi-traps with conditioned water, which had been left outside for a long time without a cover, and with deionized water. The females preferred to deposit their eggs in ovi-traps with conditioned water. Another experiment using diluted conditioned water revealed that the intensity of attractiveness for oviposition depended on the concentration of the water
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