Day-to-day and seasonal fluctuations of urban mortality in Kyoto,Japan

The study and interpretation of temporal variability in mortality requires the consideration of both exogenous and endogenous influences as underlying factors. In the present paper the relative contribution of fluctuations in daily weather was investigated using the unbiased techniques of lagged cross-correlation and spectral analyses. The study focused on patterns of daily mortality in Kyoto, Japan. Studied herein were total mortality of all ages less accidental, ischemic heart (IHD), cerebrovascular (CVD), cardiovascular (IHD + CVD), cancer and among elderly (over 70 years of age) deaths. The meteorological factors were mean, maximum and minimum daily temperature, mean barometric pressure, mean relative humidity, and mean and maximum wind speed. It was found that after extreme weather conditions, such as heat waves (with mean air temperature in excess of 30°C) or the intrusion of cold waves (with mean air temperature below 0°C), mortality increased to about three times the daily average with a lag effect of usually one—three days and up to one week. Over the year, however, weather fluctuations were found to account statistically for no more than 10% of the overall annual variability in mortality. Importantly, the short-term upswings in mortality were usually accompanied by noticeable drops in the number of deaths on the subsequent days suggesting a triggering effect of external factors. The most weather-sensitive mortality group was people over 70 years of age.     

An observational study of winter temperatures in the urban area of Houston,Texas

Measurements of the horizontal pattern of temperatures were made in the built-up area of Houston, Texas, during the nighttime hours in early winter. Temperature measurements were made during automobile traverses with supplemental values obtained from four stationary locations. Because of the simple topography of the region there were minimal effects of altitude on the observed temperatures. The analysis of the temperatures disclosed the frequently-observed pattern in which temperatures in built-up areas exceed those measured in open spaces. In spite of the relative sparseness of the residences, a heat island was observed that is similar to those of other large cities. The greatest urban-rural contrast (5°C) occurred prior to midnight, after which the temperature difference decreased as the built-up areas cooled more rapidly than the rural sites.

---

Zusammenfassung Die horizontale Temperaturverteilung im überbauten Bereich von Houston, Texas, wurde während der Nachstunden im Vorwinter gemessen. Die Temperaturmessungen erfolgten während der Stosszeiten des Autoverkehrs. Zusatzwerte wurden an 4 feststehenden Orten gewonnen. Wegen der einfachen Topographie der Region ergaben sich nur minimale Höheneffekte bei den beobachteten Temperaturen. Die Analyse der Werte ergab, dass die Temperaturen im überbauten Gebiet höher waren als im freien Bereich. Trotz der relativ geringen Dichte der Wohnhäuser, war eine Wärmeinsel ähnlich wie in anderen grossen Städten erkennbar. Der grösste Stadt-Land Unterschied von 5°C bestand vor Mitternacht. Danach verkleinerten sich die Unterschiede indem die überbauten Zonen rascher abkühlten als die Aussenbezirke.

---

Resume On a mesuré la répartition horizontale des températures durant les nuits du début de l'hiver dans la zone urbaine de Houston (Texas, USA). Ces mesures ont été effectuées en automobile, selon des parcours déterminés,et comparées à des valeurs relevées à 4 points fixes. En raison de la topographie uniforme de la région, l'influence de l'altitude est très faible sur les températures observées. L'analyse révèle ici aussi le fait observé souvent ailleurs que les surfaces construites sont plus chaudes que les espaces découverts. Malgré la faible densité des habitations, l'îlot de chaleur y fut observé dans des proportions analogues à celles d'autres grandes villes. La différence la plus accentuée entre les températures de la zone bâtie et celles de la zone rurale (5°) se rencontre avant minuit. Plus tard, cette différence diminue du fait que la partie construite se refroidit plus rapidement que la région circonvoisine.

     

Serological evidence of typhus group rickettsia in a homeless population in Houston, Texas

We tested sera from 176 homeless people in Houston for antibodies against typhus group rickettsiae (TGR). Sera from 19 homeless people were reactive to TGR antigens by ELISA and IFA. Two people had antibodies against Rickettsia prowazekii (epidemic typhus) and the remaining 17 had antibodies against Rickettsia typhi (murine typhus).     

Potential Impacts of Future Warming and Land Use Changes on Intra-Urban Heat Exposure in Houston,Texas

Extreme heat events in the United States are projected to become more frequent and intense as a result of climate change. We investigated the individual and combined effects of land use and warming on the spatial and temporal distribution of daily minimum temperature (T_min) and daily maximum heat index (HI_max) during summer in Houston, Texas. Present-day (2010) and near-future (2040) parcel-level land use scenarios were embedded within 1-km resolution land surface model (LSM) simulations. For each land use scenario, LSM simulations were conducted for climatic scenarios representative of both the present-day and near-future periods. LSM simulations assuming present-day climate but 2040 land use patterns led to spatially heterogeneous temperature changes characterized by warmer conditions over most areas, with summer average increases of up to 1.5°C (T_min) and 7.3°C (HI_max) in some newly developed suburban areas compared to simulations using 2010 land use patterns. LSM simulations assuming present-day land use but a 1°C temperature increase above the urban canopy (consistent with warming projections for 2040) yielded more spatially homogeneous metropolitan-wide average increases of about 1°C (T_min) and 2.5°C (HI_max), respectively. LSM simulations assuming both land use and warming for 2040 led to summer average increases of up to 2.5°C (T_min) and 8.3°C (HI_max), with the largest increases in areas projected to be converted to residential, industrial and mixed-use types. Our results suggest that urbanization and climate change may significantly increase the average number of summer days that exceed current threshold temperatures for initiating a heat advisory for metropolitan Houston, potentially increasing population exposure to extreme heat.     

Analysis of seasonal fluctuations in the Lotka-Volterra model

A modification of the Lotka-Volterra model was proposed. The modification takes into account the factor of seasonal fluctuations in a "predator-prey" model. In this modification, interactions between species in summer are described by the Lotka-Volterra equations; in winter, individuals of both species extinct. This generalization makes the classic model unrough, which substantially extends the field of its application. The results of numerical simulation illustrate the statement formulated above.     

Prevalence and airborne spore levels of Stachybotrys spp. in 200 houses with water incursions in Houston, Texas

Two hundred homes with a history of water incursion were sampled for fungi to determine the prevalence and airborne spore levels of Stachybotrys spp. Sampling methods included room air, surface, and wall cavity air sampling. Stachybotrys spp. were detected with at least one of the methods in 58.5% of the houses tested, but only 9.6% of the room air samples contained Stachybotrys spores. Aerosolization of Stachybotrys spores was correlated with both wall cavity and surface contamination. However, after adjustment for the surface effect, Stachybotrys spores detected in wall cavities were not a significant factor contributing to spores detected in room air samples. We conclude that Stachybotrys spp. are commonly found on water-damaged building materials. In addition, the observations made in this study suggest that the impact on the living space air is low if the fungal spores are contained within a wall cavity.     

Healthcare Resource Utilization for Recurrent Clostridium difficile Infection in a Large University Hospital in Houston,Texas

Background

There are limited data examining healthcare resource utilization in patients with recurrent Clostridium difficile infection (CDI).

Methods

Patients with CDI at a tertiary-care hospital in Houston, TX, were prospectively enrolled into an observational cohort study. Recurrence was assessed via follow-up phone calls. Patients with one or more recurrence were included in this study. The location at which healthcare was obtained by patients with recurrent CDI was identified along with hospital length of stay. CDI-attributable readmissions, defined as a positive toxin test within 48 hours of admission and a primary CDI diagnosis, were also assessed.

Results

372 primary cases of CDI were identified of whom 64 (17.2%) experienced at least one CDI recurrence. Twelve of 64 patients experienced 18 further episodes of CDI recurrence. Of these 64 patients, 33 (50.8%) patients with recurrent CDI were readmitted of which 6 (18.2%) required ICU care, 29 (45.3%) had outpatient care only, and 2 (3.1%) had an ED visit. Nineteen (55.9%) readmissions were defined as CDI-attributable. For patients with CDI-attributable readmission, the average length of stay was 6±6 days.

Conclusion

Recurrent CDI leads to significant healthcare resource utilization. Methods of reducing the burden of recurrent CDI should be further studied.     

Synergistic effects of seasonal rainfall, parasites and demography on fluctuations in springbok body condition

1. Seasonality of rainfall can exert a strong influence on animal condition and on host-parasite interactions. The body condition of ruminants fluctuates seasonally in response to changes in energy requirements, foraging patterns and resource availability, and seasonal variation in parasite infections may further alter ruminant body condition. 2. This study disentangles the effects of rainfall and gastrointestinal parasite infections on springbok (Antidorcas marsupialis) body condition and determines how these factors vary among demographic groups. 3. Using data from four years and three study areas, we investigated (i) the influence of rainfall variation, demographic factors and parasite interactions on parasite prevalence or infection intensity, (ii) whether parasitism or rainfall is a more important predictor of springbok body condition and (iii) how parasitism and condition vary among study areas along a rainfall gradient. 4. We found that increased parasite intensity is associated with reduced body condition only for adult females. For all other demographic groups, body condition was significantly related to prior rainfall and not to parasitism. Rainfall lagged by two months had a positive effect on body condition. 5. Adult females showed evidence of a 'periparturient rise' in parasite intensity and had higher parasite intensity and lower body condition than adult males after parturition and during early lactation. After juveniles were weaned, adult females had lower parasite intensity than adult males. Sex differences in parasitism and condition may be due to differences between adult females and males in the seasonal timing of reproductive effort and its effects on host immunity, as well as documented sex differences in vulnerability to predation. 6. Our results highlight that parasites and the environment can synergistically affect host populations, but that these interactions might be masked by their interwoven relationships, their differential impacts on demographic groups, and the different time-scales at which they operate.     

Composition and seasonal fluctuations of intertidal fish assemblage in Kohr al-Zubair, Northwestern Arabian Gulf

A total of 2,851 fishes belonging to 34 species and weighing 177.15 kg were caught between July 1983 and June 1984 near Kohr al-Zubair in the northwestern Arabian Gulf, using four types of fixed gillnets with different mesh sizes. Four species (Thryssa hamiltoni, Liza macrolepis, T. mystax and Nematalosa nasus) formed 82.1% of all fish while 3 species (L. macrolepis, T. hamiltoni, Pomadasys argenteus) comprised 50.3 % of the total wet weight. The abundance of species was highest during autumn and spring, clearly reflecting the high values for the diverse indices during these periods and indicating the differing biological fish utilization of Kohr al-Zubair. The high positive correlation of temperature to number of species played an important role in this abiotic factor of fish migration to and from Kohr al-Zubair. Quantitative clustering of common fish species based on individual samples showed six distinctive groups. Group I included four resident species, while groups II-VI comprised mainly seasonal species that entered the Kohr area during either warm or cold seasons.     

Diversity and seasonal fluctuations in dung beetle (Coleoptera) community in Kurukshetra,India

Five pitfall traps baited with 150–200 g of fresh cattle dung were installed for 24 h at weekly intervals. A total of 991 dung beetles from 11 genera, 31 species and three subfamilies was obtained. The community was dominated by Oniticellus spinipes individuals by 32.3%. Ten species appeared only once during the collection period and species composition and dominance changed throughout the period. The overall pattern we detected in the organization of the dung beetle community is that the species richness, abundance and diversity rise in September and the 2^nd week of October. The dung beetle community was found to be affected by season.     

First evidence for seasonal fluctuations in lichen- and bark-colonising fungal communities

Endophytic fungal communities in leaves of deciduous trees usually undergo pronounced seasonal changes. We hypothesised that such compositional shifts are predominantly caused by annuality of the leaves and therefore less pronounced in fungi colonising the perennial substrates bark and corticolous lichens. To test this hypothesis, thalli of the foliose lichen-forming fungal species Xanthoria parietina and Physconia distorta, along with the adjacent bark, were sampled during spring and autumn at two sides of a single tree in southern Germany. Analysis of clone libraries by restriction fragment length polymorphism (RFLP) revealed 588 singleton and 221 non-singleton RFLP-types of non-lichenised fungi. The communities differed significantly between host lichen species. Season and exposure had only a significant impact when the two factors were combined in the analysis. Accordingly, bark- and/or the lichen-associated fungal communities change throughout the year’s course, a finding that rejects the initial hypothesis. This survey revealed valuable information for future broad-based studies, by indicating that a relatively high diversity of non-lichenised fungi is associated with corticolous lichen thalli and the adjacent bark. Furthermore, the structure of non-lichenised fungal assemblages associated with corticolous lichen communities obviously depends at least on the following factors: ‘lichen species’, ‘exposure’, and ‘season’.     

Further study on seasonal fluctuations of Egyptian soil fungi

The seasonal fluctuations of fungi were studied in 72 soil samples collected at 10-day intervals between January 1972 and December 1973. The richest periods in the fungal population were January, March and September–December 1972, and April, May, September, November and December 1973. The poorest months were consistently June and July of 1972 and 1973 and August 1973 which are all summer months. Thirty-nine genera were isolated of which Aspergillus, Penicillium, Fusarium, Mucor, Rhizopus and Humicola were of high seasonal occurrence. Seven genera were of moderate occurrence and these were Cochliobolus,Stachybotrys, Paecilomyces, Cunninghamella, Myrothecium, Chaetomium and Sepedonium. The remaining genera were of low or rare seasonal occurrence. Aspergillus showed its highest prevalence during the periods May-September 1972 and April-August 1973. Twenty-four species of Aspergillus in addition to two varieties of A. nidulans were isolated, of which A. niger, A. fumigatus, A. terreus, A. nidulans and A. sydowii were dominant. Thirty species of Penicillium were identified, of which P. notatum, P. funiculosum and P. chrysogenum were of high seasonal occurrence. Penicillium predominated during winter and spring months. Fusarium showed its highest percentage populations during the periods February, March, April, October, November and December 1972 and February, August, September, October and November 1973. Four species of Mucor were recorded of which M. racemosus was the commonest; and its highest percentage populations were recorded in November 1972; and February, March and November 1973 which are moderate temperature months. Rhizopus was represented by two species of which R. nigricans was of high seasonal occurrence. Three species of Humicola were isolated of which H. grisea was the most common.     

Diel and seasonal physico-chemical fluctuations in a small natural West African lake

SUMMARY. 1. The waters of Opi Lake were very dilute (15–24 μS cm⁻¹at 25°C) and somewhat acid (pH 6.0–6.5), probably a result of the highly leached lateritic soils in its small drainage basin.
2. Annual minimum water temperatures were recorded during the early dry season, not during the rainy season as has been observed in most other West African water bodies. This was attributed to the influence of the Harmattan winds on the lake and the absence of pronounced rainy season flooding, as might occur in reservoirs.
3. A diel cycle of daytime thermal stratification and complete or near-complete night-time destratification occurred throughout the year.
4. During the dry season, when prevailing winds were strong and lake depth shallow, night-time destratification was accompanied by deep circulation. In the rainy season, when prevailing winds were weak and lake depth was greatest, deep vertical circulation apparently did not take place, as evidenced by anoxia in near-bottom waters. This is the reverse of the pattern seen in many tropical lakes.     

Regulation of rumen fermentation during seasonal fluctuations in food intake of muskoxen

We studied rumen fermentation of castrated adult muskoxen (Ovibos moschatus; n=4) during periods of low (May) and high (August) food intake. Turnover time (17+/-1.8 h) and volume (26+/-3.9 L) of rumen fluid were consistent between May and August and among days within each season. Rumen temperature did not vary significantly during the day (38.8+/-0.29 degrees C) in either season. Rumen osmolality (271.9+/-16.4 vs. 245.9+/-11.4 mOsm kg(-1)) and pH (6.81+/-0.31 vs. 6.39+/-0.15) were higher in May than in August indicating a shift in the allostatic set point. Rumen fluid pH was more variable in May than in August both before and after a single meal of fermentable substrate even though fermentation acids were lower in May than in August (101.0+/-11.0 vs. 126.0+/-8.74 mM). Changing proportions of minor fermentation acids indicated a shift in metabolic pathways even though bacterial numbers were similar between seasons (6.4+/-5.8x10(9) mL(-1)). Allostatic set points probably alter the homeostatic range of conditions and the microbial diversity of fermentations in herbivores from highly seasonal environments.     

Rotifer community structure in three shallow lakes: seasonal fluctuations and explanatory factors

The present work aimed at studying the rotifer communities of three shallow eutrophic lakes in Portugal (lakes Mira, Vela and Linhos). At the time of the study, Mira and Vela faced large inputs of allochthonous nutrients, while Linhos was facing terrestrialisation, with cycles of dominance-senescence of macrophytes. The three lakes differed in terms of their abiotic features, with Linhos presenting very high nutrient levels and low pH, while Vela and Mira shared most of the characteristics. The rotifer communities of these two lakes were poorly diversified but highly abundant (max. > 2000 ind l⁻¹), with a clear dominance of eurytopic euplanktonic species (mainly Keratella cochlearis). On the other hand, Linhos presented lower abundances (<1000 ind l⁻¹) but higher species richness, mainly due to macrophyte-associated taxa, such as the littoral genera Lepadella, Testudinella and Squatinella. In all lakes, summertime represented a peak in terms of abundance and diversity. Canonical correspondence analysis (CCA) identified two main environmental gradients that shape up the rotifer assemblages: a temporal gradient, mainly related to temperature, and a eutrophy gradient, associated with nitrogenous nutrients. The latter gradient is clearly dependent on between-lake variation, due to the high nutrient levels observed in lake Linhos. Variance partitioning using CCA revealed that the largest portion (27.5%) of the total variation explained (52.1%) was attributed to the interaction between lake and environmental variables.     

Biometeorological study of the seasonal variation of mortality in Japan and other countries on the seasonal disease calendar

The results of previously published statistical evaluations of morbidity and mortality statistics from 1900 to 1960 for various diseases in Japan,the United States, Egypt and several European countries are summarized. It was found that for all the diseases considered there is a monthly change in frequency distribution which led to the elaboration of a seasonal disease calendar. For Japan it was noted that the mortality peak has gradually moved from summer to winter for most diseases.This pattern has been found to exist in the highly industrialized European countries and the USA for some time, while a high summer mortality and typical seasonal disease distribution is still found in little industrialized countries such as Egypt. The deseasonality of diseases seems to be typical of industrialized countries with highly developed public health and medical services.

---

Zusammenfassung Die in früheren Arbeiten veröffentlichten Ergebnisse statistischer Untersuchungen von Morbiditäts- und Mortalitätsstatistiken von 1900 bis 1960 für verschiedene Krankheiten in Japan, den Vereinigten Staaten,Ägypten und mehreren europäischen Ländern wurden hier im Zusammenhang beschrieben. Es war gefunden worden, dass die Häufigkeitsverteilung aller berücksichtigten Krankheiten sich von Monat zu Monat ändert. Dies wurde in einem Kalender über die jahreszeitliche Verteilung der Krankheiten zusammengefasst. In Japan hat sich die Spitze der Mortalität bei den meisten Krankheiten langsam vom Sommer in die Winterperiode verschoben. Diese Verschiebung ist in den hochindustrialisierten Ländern Europas und in den Vereinigten Staaten schon früher erfolgt. Dagegen wird in den wenig industrialisierten Ländern wie Ägypten noch eine hohe Sommer-Mortalität und die typische jahreszeitliche Krankheitsverteilung gefunden. Das Verschwinden der jahreszeitlichen Häufigkeitsverteilung von Krankheiten scheint typisch zu sein für industrialisierte Länder, in denen Medizin und Gesundheitsdienst einen hohen Stand aufweisen.

---

Resume On a réuni ici les résultats de recherches statistiques publiées antérieurement sur la morbidité et la mortalité de 1900 à 1960 et concernant diverses maladies au Japon, aux Etats-Unis, en Egypte et en de nombreux pays d'Europe.On constate que la répartition des fréquences de toutes les maladies considérées varie de mois en mois. On a résumé cette constatation en un calendrier de la répartition des maladies au cours de l'année. Au Japon,le maximum de la mortalité s'est lentement déplacé de l'été vers l'hiver et cela pour la plupart des maladies. Ce décalage s'est manifesté antérieurement dans les pays hautement industrialisés d'Europe ainsi au'aux Etats-Unis. Par contre, dans les pays moins industrialisés, comme l'Egypte par exemple, on constate encore une très forte mortalité en été'et une répartition typique des maladies au cours de l'année. La disparition de la répartition des fréquence des maladies au cours de l'année semble un phénomène typique des pays industrialisés dans lesquels la médecine et les services d'hygiène publique ont atteint un niveau élevé.

---

---

This is a summary of my previous studies published in Japan.