[Impact of Emission Reduction in Different Sectors on Air Quality and Atmospheric Temperature in Eastern China].

China's emission reduction policy will focus on the synergistic control of air pollution and atmospheric warming in future. However, the impacts of emission reductions in different sectors on air quality and atmospheric temperature vary significantly. Using a two-way coupled air quality model(WRF-Chem), this study quantified the impacts of anthropogenic emission reductions from various sectors(industrial, residential, transportation, thermal power plants, and agricultural sectors) on air quality and atmospheric temperature in eastern China in September 2016. Emission reduction from industrial, residential, transportation, thermal power plant, and agricultural sources could effectively improve air quality, with PM2.5 reduction of 33.9%, 9.6%, 15.8%, 10.8%, and 26.7%, respectively; however, the weakened aerosol-radiation interactions resulted in more energy at the surface, further increasing the near-surface air temperature by 0.04, 0.03, 0.01, 0.03, and 0.09℃. At the top of the atmosphere, the net radiation flux decreased by 0.3, 0.8, 0.7, and 0.1 W·m-2 owing to the emission reduction from industrial, residential, traffic, and thermal power plant sectors, whereas the emission reduction from agricultural sources resulted in an increase in the net radiation flux of 0.8 W·m-2. On one hand, the emission reduction from agricultural sources led to a decrease in scattering aerosols and increase in the net radiation flux; contrastingly, it did not lead to a decrease in absorbing aerosols(black carbon), which could not offset the radiation increase caused by the decrease in scattering aerosols. Therefore, the emission reduction from agricultural sources led to the increase in net radiation flux at the top of the atmosphere and the most significant increase in near-surface temperature. It is noted that in the future, although emission reduction from agricultural sources will bring about significant air quality improvement, it will also consequently cause significant warming.

Quantifying the influence of transmission path characteristics on urban railway noise.

Every ambient noise study employs the source-path-receiver structure to explore the overall behaviour of sound. Noise levels are affected by changes in distance, intervening barriers, and atmospheric conditions along the transmission path between the source and the receiver. The objective of this study is to quantify the influence of transmission path characteristics for a realistic time-varying moving line source. In this context, railway noise was considered to explore the variance of noise in an urban setting over a variety of measuring distances, including 25, 50, 100, and 200 m, with variables such as air temperature, humidity, and wind condition. The data corresponding to 106 trains was collected for analysis, and it was observed that the effect of the wind was more significant for larger distances between the source and the receiver. When the sound levels were measured in two opposite wind directions, a considerable noise level difference was observed. For every 1 m/s increase in wind speed, within a distance of 50 m, the average sound attenuation induced by the upwind phenomena was 0.2 dBA. The impact of air temperature changes on received sound level from a moving source was insignificant within the range of temperatures considered in the study. The effect of humidity is less at shorter distances but at larger distances, increasingly attenuates noise levels. Analysis of variance was performed on the selected variables to determine whether the means of each group were significantly different from each other and found that train speed had a more significant impact on railway noise compared to other parameters.

Could atmospheric temperature impact on adequate colon cleansing for colonoscopy? An observational, single-institution study.

PURPOSE: Several risk factors affecting the adequacy of colon cleansing have been proposed during the last decades. However, less is known about the impact that atmospheric aspects could have on adequacy of the bowel cleansing. The study aimed to investigate if the atmospheric temperature could impact on the bowel cleansing during colonoscopy. METHODS: A prospective maintained database of the colonoscopies performed since 1st August 2017 to 31st March 2020 was retrospective reviewed. The primary outcome of the study was to identify if the atmospheric temperature was associated with inadequate colon cleansing during colonoscopy. Secondary outcome was to identify the other factors associated with an inadequate colon cleansing. RESULTS: One thousand two hundred twenty patients were enrolled. High atmospheric temperature (> 25 °C) significantly influenced the colon cleansing (p < 0.0001). Adequate colon cleansing was negatively influenced by gender (female patients were associated with higher colon cleansing rate, p = 0.013), diabetes (p < 0.0001), previous pelvic surgery (p = 0.001), use of Beta-Blocker (p = 0.001), anti-platelet (p = 0.017), angiotensin converting enzyme inhibitors (p = 0.001), the adoption of 4 L Poly Ethylene Glycol solution (p = 0.009), single-dose regimen (p < 0.0001) low patients' compliance (p < 0.0001), higher age and body mass index (p < 0.0001 and p = 0.025), lower education levels (p < 0.0001). On the contrary, admission to the ward to perform bowel preparation positively impacted on colon cleansing (p = 0.002). CONCLUSION: Atmospheric temperature could play an important role in the colon cleansing during colonoscopy, being high temperature (> 25 °C) associated with lower rate of adequate bowel cleansing. However, being this relationship never studied before, these results must be confirmed by other studies.

Temporal trend of diarrhea morbidity rate with climate change: Egypt as a case study.

Many studies have detected a relationship between diarrhea morbidity rates with the changes in precipitation, temperature, floods, droughts, water shortage, etc. But, most of the authors were cautious in their studies, because of the lack of empirical climate-health data and there were large uncertainties in the future projections. The study aimed to refine the link between the morbidity rates of diarrhea in some Egyptian governorates representative of the three Egyptian geographical divisions with the meteorological changes that occurred in the 2006-2016 period for which the medical data are available, as a case study. Medical raw data was collected from the Information Centre Department of the Egyptian Ministry of Health and Population. The meteorological data of temperature and precipitation extremes were defined as data outside the 10th-90th percentile range of values of the period of study, and their analysis was done using a methodology similar to the one recommended by the WMO and integrated in the CLIMDEX software. Relationships between the morbidity rates of diarrhea in seven Egyptian governorates and the meteorological changes that occurred in the period 2006 to 2016 were analyzed using multiple linear regression analysis to identify the most effective meteorological factor that affects the trend of morbidity rate of diarrhea in each governorate. Statistical analysis revealed that some meteorological parameters can be used as predictors for morbidity rates of diarrhea in Cairo, Alexandria, and Gharbia, but not in Aswan, Behaira, and Dakahlia where the temporal evolution cannot be related with meteorology. In Red Sea, there was no temporal trend and no significant relationships between the diarrhea morbidity rate and meteorological parameters. The predictor meteorological parameters for morbidity rates of diarrhea were found to be depending on the geographic locations and infrastructures in these governorates. It was concluded that the meteorological data that can be used as predictors for the morbidity rate of diarrhea is depending on the geographical location and infrastructures of the target location. The socioeconomic levels as well as the infrastructures in the governorate must be considered confounders in future studies.

Atmospheric-Temperature Chain Reaction towards Ultrathin Non-Crystal-Phase Construction for Highly Efficient Water Splitting.

Combining the self-sacrifice of a highly crystalline substance to design a multistep chain reaction towards ultrathin active-layer construction for high-performance water splitting with atmospheric-temperature conditions and an environmentally benign aqueous environment is extremely intriguing and full of challenges. Here, taking cobalt carbonate hydroxides (CCHs) as the initial crystalline material, we choose the Lewis acid metal salt of Fe(NO3 )3 to induce an aqueous-phase chain reaction generating free CO3 2- ions with subsequent instant FeCO3 hydrolysis. The resultant ultrathin (∼5 nm) amorphous Fe-based hydroxide layer on CCH results in considerable activity in catalyzing the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), yielding 10/50 mA ⋅ cm-2 at overpotentials of 230/266.5 mV for OER and 72.5/197.5 mV for HER. The catalysts can operate constantly in 1.0 M KOH over 48 and 45 h for the OER and HER, respectively. For bifunctional catalysis for alkaline electrolyzer assembly, a cell voltage as low as 1.53 V was necessary to yield 10 mA cm-2 (1.7 V at 50 mA cm-2 ). This work rationally builds high-efficiency electrochemical bifunctional water-splitting catalysts and offers a trial in establishing a controllable nanolevel ultrathin lattice disorder layer through an atmospheric-temperature chemical route.

Comparison of Temperature Readings, Infrared, Non-Contact Thermometer with Contact Digital Thermometer Readings in Children.

BACKGROUND: Body temperature is an important vital sign in clinical practice which can be measured via electronic contact thermometers and infrared non-contact thermometers. OBJECTIVE: To compare temperature readings taken by non contact infrared thermometer with the conventional digital axillary, rectal and oral temperature readings as well as the influence of environmental temperature on noncontact infrared thermometer readings. METHODOLOGY: A prospective study carried out in the Paediatric outpatient clinic of the Rivers State University Teaching Hospital, Nigeria from September 2020 to December 2020. Infrared noncontact forehead and jugular temperatures along with contact axillary, oral and rectal temperatures at a recorded atmospheric temperature and pressure were measured. Data collected was analysed. RESULTS: A total of 247 children aged 1month to 16 years were enrolled, the mean differences of the temperature pairs of contact and non-contact thermometry ranged from 0.45 - 0.77°C (1.64, -1.81°C) 95% LoA. The highest mean difference was found between infrared forehead and axillary [MD; 0.45(1.64,-0.73°C) 95%LoA] temperatures. There was a significant positive correlation between the mean difference of infrared forehead/ rectal temperature and atmospheric temperature (r = 0 .211 p = 0.029). Linear regression model showed that infrared forehead temperature of 37.1°C was equivalent to rectal temperature of 38°C and axillary of 37.4°C which is the standard cut off for fever. Infrared jugular of 37.2°C was equivalent to rectal of 38°C and axillary temperature of 37.4°C was equivalent to infrared jugular of 37.03°C all at a mean atmospheric temperature of 28.3±1.8°C. CONCLUSION: The mean difference by which infrared noncontact thermometry predicts core temperatures may differ based on atmospheric temperature. Infrared non-contact forehead thermometer reading of 37.1°C could be considered as the fever cut off for non-contact forehead thermometry in Nigeria in regions where the mean atmospheric temperature is 28.3±1.8°C.

CONTEXTE: La température corporelle est un signe vital important dans la pratique clinique qui peut être mesurée à l'aide de thermomètres électroniques à contact et de thermomètres infrarouges sans contact. OBJECTIF: Comparer les lectures de température prises par un thermomètre infrarouge sans contact avec les lectures de température axillaire, rectale et buccale numériques conventionnelles, ainsi que l'influence de la température ambiante sur les lectures de thermomètre infrarouge sans contact. MÉTHODOLOGIE: Une étude prospective réalisée dans la clinique pédiatrique ambulatoire du Rivers State University Teaching Hospital, au Nigéria, de septembre 2020 à décembre 2020. Températures infrarouges sans contact du front et de la jugulaire ainsi que des températures axillaire, orale et rectale de contact à une température et une pression atmosphériques enregistrées ont été mesurés. Les données recueillies ont été analysées. RÉSULTATS: Un total de 247 enfants âgés de 1 mois à 16 ans ont été inclus, les différences moyennes des paires de températures de la thermométrie avec contact et sans contact variaient de 0,45 à 0,77°C (1,64, -1,81°C) 95 % LoA. La différence moyenne la plus élevée a été trouvée entre l'infrarouge frontal et axillaire [MD; 0,45 (1,64,-0,73°C) 95 % LoA]. Il y avait une corrélation positive significative entre la différence moyenne de la température infrarouge frontale/rectale et la température atmosphérique (r = 0,211 p = 0,029). Le modèle de régression linéaire a montré que la température frontale infrarouge de 37,1 °C était équivalente à la température rectale de 38 °C et axillaire de 37,4 °C, qui est la valeur seuil standard pour la fièvre. L'infrarouge jugulaire de 37,2°C équivalait à une température rectale de 38°C et la température axillaire de 37,4°C équivalait à l'infrarouge jugulaire de 37,03°C, le tout à une température atmosphérique moyenne de 28,3±1,8°C. CONCLUSION: La différence moyenne par laquelle la thermométrie infrarouge sans contact prédit les températures centrales peut différer en fonction de la température atmosphérique. La lecture du thermomètre frontal infrarouge sans contact de 37,1 °C pourrait être considérée comme le seuil de fièvre pour la thermométrie frontale sans contact au Nigeria dans les régions où la température atmosphérique moyenne est de 28,3 ± 1,8 °C. Mots clés: Thermomètre sans contact, température rectale, température axillaire, buccale, front, jugulaire, température atmosphérique.

[Spatiotemporal Variations in Atmospheric Urban Heat Island Effects and Their Driving Factors in 84 Major Chinese Cities].

Accelerating urbanization seriously intensifies urban heat island effects in China, which in turn affects regional environment and human health. However, the spatiotemporal patterns of atmospheric urban heat island effects remain poorly understood in China as previous research is mostly based on satellite-sensed radiation temperatures. Using long-term daily meteorological observations from 1960 to 2017, this study explored the geographical distribution of atmospheric urban heat islands over diurnal, intra-annual, and inter-annual timescales in 84 major cities in China. The results show that on average, the intensity of the urban heat island reaches(0.9±1.1)℃, although large geographical variations were detected. The intensity was, overall, larger in northern China than in southern China; North China showed the largest annual intensity of(1.4±1.4)℃, and seasonal intensity variations were high in northeast and northwest China. Here, significantly higher intensity effects were measured at night[(1.2±1.1)℃] than during the day[(0.5±1.2)℃], and in summer than winter during the day, and in winter than summer during the night. Inter-annually, the annual mean urban heat island effect has increased by an average of 0.040℃ per decade, although this trend weakens after 2009. Furthermore, we found that the spatial patterns of atmospheric heat island intensity was greatly affected by climatic background conditions and the location of meteorological stations, while the long-term trends were strongly influenced by the impervious surface area. This study improves understanding of the atmospheric urban heat island effect in China and provides important insights for formulating urban land-use strategies to alleviate high temperatures and heatwaves.

Application of the Deep Neural Network in Retrieving the Atmospheric Temperature and Humidity Profiles from the Microwave Humidity and Temperature Sounder Onboard the Feng-Yun-3 Satellite.

The shallow neural network (SNN) is a popular algorithm in atmospheric parameters retrieval from microwave remote sensing. However, the deep neural network (DNN) has a stronger nonlinear mapping capability compared to SNN and has great potential for applications in microwave remote sensing. The Microwave Humidity and Temperature Sounder (Beijing, China, MWHTS) onboard the Fengyun-3 (FY-3) satellite has the ability to independently retrieve atmospheric temperature and humidity profiles. A study on the application of DNN in retrieving atmospheric temperature and humidity profiles from MWHTS was carried out. Three retrieval schemes of atmospheric parameters in microwave remote sensing based on DNN were performed in the study of bias correction of MWHTS observation and the retrieval of the atmospheric temperature and humidity profiles using MWHTS observations. The experimental results show that, compared with SNN, DNN can obtain better bias-correction results when applied to MWHTS observation, and can obtain higher retrieval accuracy of temperature and humidity profiles in all three retrieval schemes. Meanwhile, DNN shows higher stability than SNN when applied to the retrieval of temperature and humidity profiles. The comparative study of DNN and SNN applied in different atmospheric parameter retrieval schemes shows that DNN has a more superior performance.

Influence of ambient temperature and diurnal temperature variation on the premature rupture of membranes in East China: A distributed lag nonlinear time series analysis.

BACKGROUND: Extreme ambient temperature has an adverse effect on pregnancy outcomes, but the conclusions have been inconsistent. The influence of ambient temperature and diurnal temperature variation on the premature rupture of membranes (PROM) needs further study. METHODS AND FINDINGS: The daily data of PROMs, daily meteorological and air pollutant were obtained. After controlling for potential confounding factors, the quasi-Poisson generalized additive model (GAM) combined with the distributed lag nonlinear model (DLNM) was used to analyze the association between temperature or diurnal temperature variation and PROM, including preterm premature rupture of membranes (PPROM) and term premature rupture of membranes (term PROM). Compared with the median temperature(18.7 °C), the mean temperature of 5-7 days lagging beyond 31.5 °C and below -1.5 °C was positively correlated with PROM; the mean temperature had more sensitive effect on the term PROM. Exposure to extremely high temperatures (97.5th percentile, 32 °C) had a 6-day lagging relative risk (RR) (95% CI: 1.005-1.160) of 1.08 for PROM and a 6-day lagging RR of 1.079 (95% CI: 1.005-1.159) for term PROM; Exposure to a high diurnal temperature variation (diurnal temperature variation greater than 16 °C) was positively correlated with the term PROM. Compared with the 2.5th percentile diurnal temperature variation (2 °C), exposure to the 95th percentile diurnal temperature variation (17 °C) significantly increased the risk of term PROM (RR: 1.229, 95% CI: 1.029-1.467). CONCLUSIONS: Exposure to a high-temperature and a high diurnal temperature variation environment will increase the relative risks of PROM. For pregnant women in the 3rd trimester, it is important to reduce exposure to extremely high-temperatures and greater diurnal temperature changes.

A simple experiment on global warming.

A simple experiment has been developed to demonstrate the global warming potential of carbon dioxide (CO2) gas in the Earth's atmosphere. A miniature electric resistance heating element was placed inside an inflatable balloon. The balloon was filled with either air or CO2. Whereas the CO2 partial pressure on the earth's atmosphere is approximately 4 × 10-4 atm, in this experiment, a high partial pressure of CO2 (1 atm) was used to compensate for the short radiation absorption path in the balloon. The element was heated to approximately 50°C, the power was then switched off and the element's cooling trends in air and in CO2 were monitored. It took a longer time to cool the heating element back to ambient temperature in CO2 than in air. It also took longer times to cool the element in larger size balloons and in pressurized balloons when they were filled with CO2. To the contrary, the balloon size or pressure made no difference when the balloons were filled with air. A simple mathematical model was developed, and it confirmed that the radiative heat loss from the element decreased significantly in CO2. This investigation showed that the cooling rate of an object, with surface temperature akin to temperatures found on Earth, is reduced in a CO2-rich atmosphere because of the concomitant lower heat loss to its environment.

COVID-19: relationship between atmospheric temperature and daily new cases growth rate.

Purpose: The novel coronavirus (severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)) first appeared in Wuhan, China, in December 2019, and rapidly spread across the globe. Since most respiratory viruses are known to show a seasonal pattern of infection, it has been hypothesised that SARS-CoV-2 may be seasonally dependent as well. The present study looks at a possible effect of atmospheric temperature, which is one of the suspected factors influencing seasonality, on the evolution of the pandemic. Basic procedures: Since confirming a seasonal pattern would take several more months of observation, we conducted an innovative day-to-day micro-correlation analysis of nine outbreak locations, across four continents and both hemispheres, in order to examine a possible relationship between atmospheric temperature (used as a proxy for seasonality) and outbreak progression. Main findings: There was a negative correlation between atmospheric temperature variations and daily new cases growth rates, in all nine outbreaks, with a median lag of 10 days. Principal conclusions: The results presented here suggest that high temperatures might dampen SARS-CoV-2 propagation, while lower temperatures might increase its transmission. Our hypothesis is that this could support a potential effect of atmospheric temperature on coronavirus disease progression, and potentially a seasonal pattern for this virus, with a peak in the cold season and rarer occurrences in the summer. This could guide government policy in both the Northern and Southern hemispheres for the months to come.

Habitat Preferences and Trophic Position of Brachydiplax chalybea flavovittata Ris, 1911 (Insecta: Odonata) Larvae in Youngsan River Wetlands of South Korea.

In freshwater ecosystems, habitat heterogeneity supports high invertebrate density and diversity, and it contributes to the introduction and settlement of non-native species. In the present study, we identified the habitat preferences and trophic level of Brachydiplax chalybea flavovittata larvae, which were distributed in four of the 17 wetlands we examined in the Yeongsan River basin, South Korea. Larval density varied across four microhabitat types: open water area, and microhabitats dominated by Myriophyllum aquaticum, Paspalum distichum, and Zizania latifolia. Microhabitats dominated by M. aquaticum had the highest larval density, followed by those dominated by P. distichum. The larvae were more prevalent in silt sediments than in plant debris or sand. Stable isotope analysis showed that B. chalybea flavovittata is likely to consume, as a food source, other species of Odonata larvae. We conclude that successful settlement of B. chalybea flavovittata can be attributed to their habitat preferences. As temperature increases due to climate change, the likelihood of B. chalybea flavovittata spreading throughout South Korea increases. We, therefore, recommend continued monitoring of the spread and ecological impacts of B. chalybea flavovittata.

A Case-Crossover Study to Investigate the Effects of Atmospheric Particulate Matter Concentrations, Season, and Air Temperature on Accident and Emergency Presentations for Cardiovascular Events in Northern Italy.

Atmospheric particulate matter (PM) has multiple adverse effects on human health, high temperatures are also associated with adverse health outcomes, and the frequency of cardiovascular events (CVEs) varies with season. We investigated a hypothesized increase in PM-related accident and emergency (A&E) presentations for CVE with high temperature, warm season, days of high influenza incidence, and in people with a cancer diagnosis, using a time-stratified case-crossover study design. Outcomes were associations of A&E presentation for CVE with atmospheric PM ≤ 10 µm (PM10), season, and air temperature. PM10 levels in the municipality of residence (exposure variable) were estimated by modeling data from local monitoring stations. Conditional logistic regression models estimated odds ratios (OR) with 95% confidence intervals (CI) for presentations in relation to supposed influencers, adjusting for confounders. Study participants were all who presented at the A&E of a large hospital near Milan, Italy, for a CVE (ICD-9: 390-459) from 1st January 2014 to 31st December 2015. There were 1349 A&E presentations for CVE in 2014-2015 and 5390 control days. Risk of A&E presentation was significantly increased on hot days with OR 1.34 (95%CI 1.05-1.71) per 10 µg/m3 PM10 increment (as mean PM10 on day of presentation, and 1 and 2 days before (lags 0-2)), and (for lag 0) in autumn (OR 1.23, 95%CI 1.09-1.37) and winter (OR 1.18, 95%CI 1.01-1.38). Risks were also significantly increased when PM10 was on lag 1, in people with a cancer diagnosis in the spring and summer months (1.88, 95%CI 1.05-3.37), and on days (lags 0-2) of high influenza incidence (OR 2.34, 95%CI 1.01-5.43). PM10 levels exceeded the 50 µg/m3 "safe" threshold recommended by the WHO and Italian legislation for only 3.8% of days during the warm periods of 2014-2015. Greater risk of A&E presentation for CVE in periods of high PM10 and high temperature suggests that "safe" thresholds for PM10 should be temperature-dependent and that the adverse effects of PM10 will increase as temperatures increase due to climate change.

Atmospheric temperature and pressure influence the onset of spontaneous pneumothorax.

BACKGROUND: The aim of the study was to examine the influence of the changes in the atmospheric temperature (ATemp) and the atmospheric pressure (APres) on the occurrence of a spontaneous pneumothorax (SP). PATIENTS AND METHODS: From January 2000 to March 2014, 192 consecutive SP events were examined. The ATemp and APres data at the onset of SP, as well as those data at 12, 24, 36, 48, 60, and 72 h prior to the onset time, were analyzed. RESULTS: The frequencies of SP occurrence were not statistically different according to the months or seasons, but were statistically different according to the time period (P < .01) and SP events occurred most frequently from 12:00 to 18:00. SP events frequently occurred at an ATemp of 25 degrees Celsius or higher. There was a significantly negative correlation between the APres and the ATemp at the SP onset time. The values of change in the APres from 36 to 24 h prior to SP onset were significantly lower than the preceding values. CONCLUSIONS: In this study, we observed that a SP event was likely to occur in the time period from 12:00 to 18:00, at an ATemp of 25 degrees Celsius or higher, and at 24-36 h after a drop of APres.

Numerical study of a buoyant plume from a multi-flue stack into a variable temperature gradient atmosphere.

Air pollution is one of the major global hazards and industries have been one of its major contributors. This paper primarily focuses on analyzing the dispersion characteristics of buoyant plumes of the pollutant released from a multi-flue vertical stack into a variable temperature gradient atmosphere (α) in a constant-velocity cross wind using two stack configurations-inline and parallel. The study is conducted for different Froude numbers, Fr = 12.64, 9.55, and 8.27. The atmospheric temperature gradients considered for the study are 0, +1, +1.5, and +2 K/100 m. The numerical study is done using the commercial computational fluid dynamics (CFD) code FLUENT. The effects of stack configuration, α, and Fr on the plume characteristics are presented. It is observed that the plume rises higher and disperses over a larger area with the inline configuration due to better mixing and shielding effect. With higher α, it is seen that the plume rises initially and then descends due to variation of the buoyant force. The plume rise initially is strongly influenced by the momentum of the jet, and as it moves downstream, it is influenced by the cooling rate of the plume. Furthermore, the plume rises higher and disperses over a larger area with a decrease in Fr.

SU-E-T-303: Practical Considerations for Maximizing Heat Production in Novel Thermo-Brachytherapy Seed Prototype.

PURPOSE: Our recently proposed thermo-brachytherapy seed offers a convenient approach to radiation sensitization with heat in treatment of solid tumors through concurrent administration of hyperthermia and brachytherapy. The seed consists of a titanium capsule, containing radioactive I-125 and a ferromagnetic core, serving as a source of self-regulating hyperthermia when placed in an alternating electromagnetic field. We present an experimental study of the magnetic properties of ferromagnetic Ni-Cu alloy, and develop a protocol for obtaining the material capable of the maximum heat generation. Based on the practically achievable temperature interval we evaluate the effect of thermal expansion on the seed components during the hyperthermia treatment. METHODS: Alloy samples of Ni1-xCux (0.28= × =0.3) were prepared by arc melting method in argon atmosphere. The ingots were annealed in vacuum at 1000°C for 12 hours. These samples were cut into pieces and used for magnetization measurements with SQUID magnetometer. The thermal expansion along greatest dimension of each component of the purposed seed was estimatedfor temperature increase from 37 to 60 ËsC. RESULTS: The annealed samples show sharp Curie transition at temperature TC∼50°C, varying with the alloy concentration. However, the un-annealed sample does not show the clear transition, thus indicating a strong influence of thermal treatments on the magnetic properties of the Ni-Cu alloy. The annealing favors atomic diffusion, and leads a sample homogenization, minimizing composition fluctuations and maximizing the heat generation. The effect of the temperature rise on the thermal expansion of each component of the seed was found to be negligible. CONCLUSIONS: We have established the thermal annealing protocol resulting in the maximum heat generation from the Ni- Cu alloy core. The negligible change in dimensions of the seed components due to heating assures the safety of the implementation of thermo-brachytherapy seed for hyperthermia treatments. This project is supported through NIH grant # 1 R41 CA153681-01A1.

Morphotype community structure of ectomycorrhizas on Douglas fir (Pseudotsuga menziesii Mirb. Franco) seedlings grown under elevated atmospheric CO2 and temperature.

Mycorrhizas alter the acquisition of carbon and nutrients, thereby affecting numerous plant and ecosystem processes. It is important, therefore, to determine how mycorrhizal populations will change under possible future climate conditions. Individual and interactive effects of elevated atmospheric CO2 concentration and atmospheric temperature were assessed in a 2×2 factorial design [ambient and elevated (200 ppm above ambient) CO2 concentrations, and ambient and elevated (4°C above ambient) temperatures]. In June 1993, 2-year-old Douglas fir (Pseudotsuga menziesii Mirb. Franco) seedlings were planted in 12 environment-tracking chambers (n=3) containing reconstructed, low-nitrogen, native forest soil. Climate treatments were imposed shortly thereafter, and the seedlings grew until June 1997. Soil cores were taken twice per year during the exposure period. We present findings on changes in the community structure of ectomycorrhizal (ECM) root tips, categorized into morphotypes using gross morphological traits. A diverse and stable community of morphotypes (a total of 40) was encountered; no more than 30 of which were seen at any sampling time. In the first sample, there were only 15 morphotypes found in the 12 chambers. Morphotype numbers increased during the first half of the experiment, remaining fairly constant thereafter. Near the end of the exposure, elevated-temperature treatments maintained more morphotypes than ambient treatments. However, overall, absolute measures (number of ECM tips) were affected primarily by CO2 treatment, whereas proportional measures (e.g., Simpson's index) were affected primarily by temperature. While some morphotypes were negatively affected seasonally by higher temperatures (putative Rhizopogon group), others (Cenococcum) seemed to thrive. Underlying the dominant patterns of change in diversity, driven by the Rhizopogon group, subdominant populations responded slightly differently. Community diversity through time tended to increase at a greater rate for all subdominant populations compared with the rate when dominant populations were included.