Microbial responses to changes in land use

Background/Question/Methods
Land use change is one of the greatest threats to biodiversity worldwide. This is especially true for land use change that results in the destruction of intact forest, or "deforestation”. Deforestation is causing a loss of biological diversity on an unprecedented scale, especially in the Tropics. It is unclear how the majority of the biodiversity on Earth – microbial biodiversity – is responding to these extraordinary rates of deforestation. I will provide an overview of our current understanding of microbial responses to deforestation. I will focus, as an example, on our current research regarding the effects of deforestation on the diversity of arbuscular mycorrhizal fungi (AMF), bacteria and archaea within Amazon Rainforest soils. This study takes advantage of an established chronosequence of primary rainforest, pastures of various ages, and secondary rainforest to determine the effect of deforestation on the taxonomic, phylogenetic and functional diversity of soil microorganisms, assayed using culture-independent methods.

Results/Conclusions
There is increasing evidence that deforestation significantly affects microbial diversity, and that “recovery” of microbial diversity in secondary forest soils is incomplete. For example, rarefaction curves suggest that the accumulation of AMF taxa is higher for Amazon primary forest soil relative to secondary forest soil. In addition, the community composition varies with land use; three AMF taxa were shared between primary and secondary forests, seven were found only in primary forest, and three were found exclusively in secondary forest soil. We also observed that the phylogenetic diversity of AMF is more reduced in secondary forest soils than expected given the regional pool of AMF taxa.

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The electroretinogram:a useful tool for evaluating age-related macular disease?

With an ageing population, the number of age-related macular disease (ARMD) cases will inevitably rise. This gives greater impetus for the need to identify the disease earlier and assess treatments to slow disease progression. Differing electroretinogram (ERG) modalities have been reviewed in relation to the objective assessment of retinal function in ARMD and for monitoring the effectiveness of clinical interventions. Conflicting results have been found with regard to the efficacy of ERG findings in the investigation of ARMD in previous years. The newer multifocal ERG paradigm provides spatial topographical information about retinal function in ARMD. It has shown promising results in monitoring effectiveness of clinical interventions and studies are continuing in this area. Better knowledge of retinal function in ARMD may lead to enhanced treatments at each phase of the disease

What's in a name? A call to reframe non-communicable diseases.

The global health community does not spend much time on branding, which perhaps explains why existing classifications for the three largest groups of diseases are both outdated and counterproductive. The first Global Burden of Disease study1 described infectious diseases, non-communicable diseases (NCDs), and injuries. This grouping reflected a predominantly infectious disease burden in low-income and middle-income countries, which has since tilted towards NCDs. A name that is a longwinded non-definition, and that only tells us what this group of diseases is not, is not befitting of a group of diseases that now constitute the world's largest killer

Superdomain Structure in Epitaxial Tetragonal PZT Thin Films Under Tensile Strain

The a/c domain pattern of tetragonal PbZr0.10Ti0.90O3 thin films under tensile misfit strain is investigated by piezoresponse force microscopy and X-ray diffraction. The results show a hierarchical ordering of the dense a/c domain structure into larger superstructures. The latter exhibit a preferred orientation and occasionally form distinct patterns such as flux closure loops of the net polarization. Additionally, the residual strain is measured with reciprocal space maps and the a-domain fraction is determined by theoretical calculations and correlated with results from rocking curve scans

Planar Superconducting Resonators with Internal Quality Factors above One Million

We describe the fabrication and measurement of microwave coplanar waveguide resonators with internal quality factors above 10 million at high microwave powers and over 1 million at low powers, with the best low power results approaching 2 million, corresponding to ~1 photon in the resonator. These quality factors are achieved by controllably producing very smooth and clean interfaces between the resonators' aluminum metallization and the underlying single crystal sapphire substrate. Additionally, we describe a method for analyzing the resonator microwave response, with which we can directly determine the internal quality factor and frequency of a resonator embedded in an imperfect measurement circuit.Comment: 4 pages, 3 figures, 1 tabl

Influence of myocardial oxygen demand on the coronary vascular response to arterial blood gas changes in humans

It remains unclear if the human coronary vasculature is inherently sensitive to changes in arterial PO2 and PCO2 or if coronary vascular responses are the result of concomitant increases in myocardial O2 consumption/demand (MVO2). We hypothesized that the coronary vascular response to PO2 and PCO2 would be attenuated in healthy men when MVO2 was attenuated with β1-adrenergic receptor blockade. Healthy men (n=11; age: 25 {plus minus} 1 years) received intravenous esmolol (β1-adrenergic receptor antagonist) or volume-matched saline in a double-blind, randomized, crossover study, and were exposed to poikilocapnic hypoxia, isocapnic hypoxia, and hypercapnic hypoxia. Measurements made at baseline and following 5-min of steady state at each gas manipulation included left anterior descending coronary blood velocity (LADV; Doppler echocardiography), heart rate and arterial blood pressure. LADV values at the end of each hypoxic condition were compared between esmolol and placebo. Rate pressure product (RPP) and left-ventricular mechanical energy (MELV) were calculated as indices of MVO2. All gas manipulations augmented RPP, MELV, and LADV but only RPP and MELV were attenuated (4-18%) following β1-adrenergic receptor blockade (P<0.05). Despite attenuated RPP and MELV responses, β1-adrenergic receptor blockade did not attenuate the mean LADV vasodilatory response when compared to placebo during poikilocapnic hypoxia (29.4{plus minus}2.2 vs. 27.3{plus minus}1.6 cm/s) and isocapnic hypoxia (29.5{plus minus}1.5 vs. 30.3{plus minus}2.2 cm/s). Hypercapnic hypoxia elicited a feed-forward coronary dilation that was blocked by β1-adrenergic receptor blockade. These results indicate a direct influence of arterial PO2 on coronary vascular regulation that is independent of MVO2

Conversion of Cerrado into agricultural land in the south-western amazon: carbon stocks and soil fertility.

Mudanças de uso da terra e práticas de manejo modificam a dinâmica do C e a fertilidade do solo. Este estudo avaliou as implicações dos sistemas de cultivo (NT e CT) nos estoques de C e de nutrientes e identificou inter-relações entre estes estoques e outros atributos da fertilidade do solo em Latossolo após a mudança do uso da terra no cerrado amazônico. Os estoques de C e de nutrientes (P, K, Ca e Mg) ajustados pela massa equivalente do solo sob cerrado (CE), foram maiores principalmente sob NT. Após a adoção do NT, exceto em 2NT, os estoques de C foram maiores em relação às demais áreas avaliadas. Correlações entre estoques de C e de nutrientes revelaram algumas correlações positivas com Ca e Mg nas áreas sob NT, devido ao uso continuo de calcário, à maior quantidade de resíduos culturais e ao não revolvimento do solo, associado à correlações positivas com CTC, saturação por bases e pH. A correlação positiva (r = 0,91, p < 0,05) entre estoques de C e CTC em CE indica a importante contribuição da MOS na CT de solos tropicais, embora os sítios de troca estejam ocupados principalmente por H + Al. Estoques de P e K mostraram correlações positivas com estoques de C em CE (0,81 e 0,82; respectivamente), indicando a alta relação de P e K com a MOS em ecossistemas naturais. A alta variabilidade espacial associada à aplicação de fertilizantes (P e K) no sulco de plantio pode ter mascarado os resultados dos estoques. A principal fonte destes nutrientes para o solo foi o fertilizante aplicado e não a MOS