Radiographic spectrum of adult pulmonary tuberculosis in a developed country

AbstractSetting. Bispebjerg Hospital, Department of Pulmonary Medicine P. The referral centre of adult tuberculosis in the municipality of Copenhagen, Denmark.Objective. To evaluate the radiographic spectrum of pulmonary tuberculosis (TB) in adults in a low-prevalence country and to correlate radiographic appearances with bacteriological results, clinical and demographic data.Design. Retrospective review of medical files on 548 cases with pulmonary TB according to the criteria of WHO.Results. Usual radiographic pattern of reactivating TB, with upper lobe involvement, was found in 92% (n=504). eight percent (n=44) showed unusual X-ray patterns for adults, such as isolated lower lobe infiltrations (n=19), hilar adenopathy (n=10), miliary TB (n=7), tuberculoma (n=2), pleural effusion (n=1) and normal chest X-ray (n=3). Eighty-nine percent of cases with cavitary lesions were positive by microscopy.Conclusion. The risk of missing a diagnosis of pulmonary TB may be high if patients present with an X-ray unusual for TB, but this is fortunately seen only in 8% of cases of pulmonary tuberculosis. Unusual X-ray is more commonly found in patients with concomitant disease, such as diabetes and cancer.If chest X-ray shows cavities, but the smear is negative for Mycobacterium, TB is unlikely and further diagnostic procedures should be performed without waiting for culture results

Breakage Susceptibility of Blended Corn

A test of the breakage susceptibility of blended corn was conducted with four moisture levels of dry corn (8, 9, 11, and 8.9% desiccant) blended with 24.4% moisture corn to two theoretical moisture levels (15.5 and 20%). The study showed that blending wet and dry corn increases the Stein breakage 0.74 to 4.47 points for a 15.5% blend and 1.54 to 10.6 points for a 20% moisture blend. The breakage in local handling due to blending wet and dry corn is likely to be from 0.1 to 1.7%, which will probably not result in a discount at the time of sale

15N tracing to elucidate links between biodiversity and nitrogen cycling in a grassland experiment

Nitrogen (N) cycling is a fundamental ecosystem function of high complexity because N undergoes many transformations in soil and vegetation. The effect of biodiversity loss on ecosystem functions in general, and on N cycling in particular, was studied in several manipulative field experiments. To generate a comprehensive view of the influence of species richness on all major N transformations, we conducted laboratory incubations, in which we added 15N-labeled ammonium and nitrate to soil samples of the “Jena Experiment”, a manipulative large scale, long-term biodiversity experiment in grassland. The experimental site is located in Jena, Germany. The design consists of 4 blocks and 82 plots with 1-60 species and 1-4 functional groups (grasses, legumes, small herbs, tall herbs). Approx. 400 g of field-fresh soil was sampled from each plot of one of the 4 blocks and divided into three aliquots of 100 g each. In order to trace N turnover, we amended the incubations (in triplicate) either with 15N-labelled (98 at%) ammonium, nitrate, or with a mixture of both. The samples were incubated for two months at 20°C. Soil solution was extracted 1, 2, 4, 9 and 16 days after 15N application by percolating 100 mL of nutrient solution through each vessel. Concentrations of NH4-N, NO3-N and total N in the extracts were determined with colorimetric methods. The N-isotopic composition in nitrate was analyzed by isotope ratio mass spectrometry (IRMS) using the denitrifier method. Ammonium N isotope ratios were determined using the “hypobromite oxidation” method, in which ammonium-N is converted to nitrite followed by azide reaction to nitrous oxide and IRMS analysis. The results will be comprehensively evaluated in a quantitative context using the modelling approach of Müller et al. (2007) to determine the size of six N pools and the rates of nine N transformations. Links between N transformation rates, N-pool size and plant species richness will be verified with the help of ANOVA

Sodium demand of microorganisms in the phyllosphere and the organic layer of a tropical montane forest in south Ecuador

Recent studies raise the hypothesis that Na shortage restricts decomposition and affects the carbon cycle in tropical forests. When Na concentrations in soils are low and the stands are far off-coast, they do not receive substantial Na inputs from the atmosphere. Since terrestrial plants have low concentrations of Na, which is not considered as an essential element, the demand of soil fauna may not be covered. Yet, in contrast to animals, little is known of Na demands of fungi and phyllosphere microorganisms. We present results from a study on Na limitation in a montane forest ecosystem in South Ecuador, which is located on the eastern cordillera of the Andes. We tested the hypotheses that (1) the study area is characterized by low Na concentrations because of low deposition rates with incident precipitation (wind directions mainly from the Amazonian Basin), (2) decomposition processes are limited by fauna and fungal Na restrictions and (3) Na is retained in the canopy because of Na limitation of microorganisms in phyllosphere. Since 1998, we measure Na fluxes in rainfall, throughfall, stemflow, litter leachate, litterfall and organic layer in a microcatchment under an undisturbed lower montane rainforest. Results reveal comparatively low Na concentrations in the ecosystem and similar Na concentrations in throughfall and stemflow. Since Na fluxes are lower with throughfall than with incident rainfall, we conclude that Na is retained in the canopy. To explore the role of the phyllosphere in Na retention we sampled leaves covered by phyllosphere microorganisms and leaves without phyllosphere cover from several tree species, which were sprayed with a NaCl solution containing 0.5 mg L-1 Na, corresponding to the Na concentration in incident rainfall in our study area. Additionally, responses of litter decomposition to Na additions and the involved interaction of soil fungi and fauna were tested in a litterbag experiment at two sites (1000 and 2000 m a.s.l.). Results revealed enhanced decomposition rates following Na additions, though only in the presence of soil fauna. These results might have future ecosystem implications, since our time series showed that total Na deposition decreased within the past 15 years from ca. 40 kg ha-1 a-1 to 10 kg ha-1 a-1, suggesting a potential role of Na in regulating ecosystem processes

Base metal budgets of a small catchment in a tropical montane forest in South Ecuador

In a tropical montane rain forest in south Ecuador, the alkali and earth alkali metals Ca, Mg, K, and Na are supplied by weathering of the parent substrate consisting of phyllites and metasandstones and by atmospheric inputs. Phases of acid deposition are interrupted by alkalinization through episodic basic dust deposition. Although the biological productivity of most terrestrial ecosystems is thought to be N- and/or P-limited, there is increasing evidence that the essential plant nutrients K, Na, Mg and Ca can also limit biological functioning. We quantified biological and geochemical contributions to base metal fluxes and set up a metal budget of a ca. 9.1-ha large catchment from 1998 to 2013. The catchment is characterized by a high annual interception loss (28–50 %) and a low contribution of stem flow to throughfall. Mean total annual soil input (throughfall + stemflow + litterfall) was 13800 ± 1500 mg m-2 (Ca, mean ± SD), 19000 ± 1510 (K), 4690 ± 619 (Mg) and 846 ± 592 (Na) of which 22 ± 6 % (Ca), 45 ± 16 (K), 39 ± 10 (Mg) and 84 ± 33 (Na) were leached to soil horizons below the organic layer. The three nutrient metals Ca, K and Mg were thus to a large part retained in the biotic part of the catchment. The canopy budget of K was consistently and most pronouncedly negative. The canopy budgets of Ca and Mg were closely correlated and in most years negative, while the budget of Na was consistently positive, indicating net retention of this element in the canopy. The mineral soil retained 79–94 % of Ca, K and Mg, while Na was net released from the mineral soil. The size of mainly biologically controlled aboveground fluxes of Ca, K and Mg was 1-2 orders of magnitude larger than that of mainly geochemically controlled fluxes which are driven by sorption to soil and weathering. Annual net hydrological fluxes (bulk deposition – stream flow) were –66 ± 278 mg m-2 (Ca), 361 ± 421 (K), –188 ± 159 (Mg) and –1700 ± 587 (Na). If estimated dry deposition was included, the system accumulated 86 kg Ca ha-1 and 199 kg K ha-1, had a nearly balanced budget of Mg (+0.3 kg ha-1) and lost 56 kg of Na ha-1 in the last 15 years. The strongest driver of all budgets was the input flux into the various compartments

Biochar amendment did not influence the growth of two tree plantations on nutrient-depleted Ultisols in the south Ecuadorian Amazon region

The literature suggests that biochar increases the fertility of degraded, nutrient-poor tropical soils. We hypothesized that the addition of biochar (a) increases tree growth in two plantations on Ultisols in the south Ecuadorian Amazon region, (b) reduces litterfall during the dry season because the soil remains moister, and (c) improves the benefit–cost ratio of the plantation. We grew two tree species—the native leguminous Schizolobium parahyba var. amazonicum (Ducke) Barneby and the exotic Gmelina arborea Roxb—and used a full factorial split-split-plot design of all treatments for both tree species at each of two sites. The treatments included the amendment of mineral fertilizer plus lime, 3 and 6 t ha$^{-1}$ biochar, and a control. The plots were replicated three or four times. Tree height (TH), basal diameter (BD), and diameter at breast height (DBH) were measured several times during 51 mo after planting in September 2009 and litterfall during 12 mo (March 2012–February 2013). The site and the mineral fertilizer plus lime treatment had significant effects on TH, BD, and DBH. The amendment of mineral fertilizer plus lime increased TH, BD, and DBH by 47, 43, and 58%, respectively, relative to the control. The litterfall of G. arborea was on average 84% higher than that of S. parahyba. The amendment of biochar did not significantly influence TH, BD, DBH, or litterfall. The benefit–cost ratio of wood production was >1 in the mineral fertilizer plus lime treatment and controls but <1 in the biochar treatments and decreased with increasing addition of biochar. Our results demonstrate that the assumption that biochar can be used to improve the fertility of degraded Amazon soils cannot be generalized

Cadmium, copper and zinc stable isotopes as analytical tool to trace sources and processes in agricultural systems

In agriculture, mineral phosphate (P) fertilizer application leads to an unintended input of Cadmium (Cd) into agricultural systems. Cd is highly toxic and its incorporation into the food chain endangers human health. Copper (Cu) and zinc (Zn) are used as feed additives and pharmaceuticals and can accumulate with farmyard manure in agricultural soils. Although being micronutrients, high Cu and Zn concentrations are toxic. Former studies revealed Cd, Cu and Zn accumulations in Swiss agricultural soils in the past decades. However, these studies were not completely based on in-situ measured data. The aim of this study was to fill this gap and measure Cd, Cu and Zn fluxes at selected Swiss agricultural sites. Specifically, we aimed to trace the metals in the soil and to differentiate between anthropogenic and geogenic sources. Additionally, we further elucidated metal redistribution in Swiss agricultural systems, based on the measurements of stable metal isotope ratios of different system pools. For that purpose, metal balances of three arable (Cd) and three grassland (Cu &amp; Zn) sites were determined by measuring the soil metal concentrations and all inputs (bulk deposition, mineral P fertilizers, manure &amp; parent material) and outputs (seepage water, crop &amp; grass harvest) during one hydrological year (May 2014 – May 2015). Furthermore, stable metal isotopes of the soil and all inputs and outputs were (Cd) and will be (Cu &amp; Zn) determined. Cd mass balances showed losses for wheat cultivation (-0.01 to -0.35 g ha-1 y-1) and accumulations for barley cultivation (0.18 to 0.71 g ha-1 y-1). Isotopic ratios in wheat (∆114/110Cdstraw-grain = -0.34 to -0.38‰) and barley plants (-0.44 to -0.82‰) revealed that uptake and retranslocation of Cd in the plants is driven by physiological processes to reduce toxic Cd impacts. Cu and Zn mass balances showed that manure application is by far the most important Cu (146-340 g ha-1 y-1) and Zn (947-1’742 g ha-1 y-1) input. Inputs with bulk deposition and through parent material weathering were by 1-2 orders of magnitude smaller. Beside the Cu and Zn budgets, stable isotope data (not yet analysed) will be presented and discussed to assess the biogeochemical processes and redistribution of (anthropogenic) Cu and Zn in agricultural systems