Soil microbial communities in restored and unrestored coastal dune ecosystems in California

Most restoration projects involving invasive plant eradication tend to focus on plant removal with little consideration given to how these invasives change soil microbial communities. However, soil microorganisms can determine invasibility of habitats and, in turn, be altered by invasives once established, potentially inhibiting native plant establishment. We studied soil microbial communities in coastal dunes with varying invasion intensity and different restoration approaches (herbicide, mechanical excavation) at Point Reyes National Seashore. Overall, we found evidence of a strong link between bacterial and fungal soil communities and the presence of invasives and restoration approach. Heavily invaded sites were characterized by a lower abundance of putatively identified nitrifiers, fermentative bacteria, fungal parasites, and fungal dung saprotrophs and a higher abundance of cellulolytic bacteria and a class of arbuscular mycorrhizal fungi (Archaeosporomycetes). Changes in soil microbiota did not fully dissipate following removal of invasives using herbicide, with exception of reductions in cellulolytic bacteria and Archaeosporomycetes abundance. Mechanical restoration effectively removed both invasives and soil legacy effects by inverting or “flipping” rhizome-contaminated surface soils with soils from below and may have inadvertently induced other adverse effects on soils that impeded reestablishment of native dune plants. Land managers should consider additional measures to counteract lingering legacy effects and/or focus restoration efforts in areas where legacy effects are less pronounced

Symmetry breaking in small rotating cloud of trapped ultracold Bose atoms

We study the signatures of rotational and phase symmetry breaking in small rotating clouds of trapped ultracold Bose atoms by looking at rigorously defined condensate wave function. Rotational symmetry breaking occurs in narrow frequency windows, where the ground state of the system has degenerated with respect to the total angular momentum, and it leads to a complex wave function that exhibits vortices clearly seen as holes in the density, as well as characteristic vorticity. Phase symmetry (or gauge symmetry) breaking, on the other hand, is clearly manifested in the interference of two independent rotating clouds.Comment: 4 pages, 2 figure

Low energy excitations of double quantum dots in the lowest Landau level regime

We study the spectrum and magnetic properties of double quantum dots in the lowest Landau level for different values of the hopping and Zeeman parameters by means of exact diagonalization techniques in systems of N=6 and N=7 electrons and filling factor close to 2. We compare our results with those obtained in double quantum layers and single quantum dots. The Kohn theorem is also discussed.Comment: 23 pages, 4 figures, 1 table; references added; journal versio

Vortex nucleation in mesoscopic Bose superfluid and breaking of the parity symmetry

We analyze vortex nucleation in mezoscopic 2D Bose superfluid in a rotating trap. We explicitly include a weakly anisotropic stirring potential, breaking thus explicitly the axial symmetry. As the rotation frequency passes the critical value $\Omega_c$ the system undergoes an extra symmetry change/breaking. Well below $\Omega_c$ the ground state is properly described by the mean field theory with an even condensate wave function. Well above $\Omega_c$ the MF solution works also well, but the order parameter becomes odd. This phenomenon involves therefore a discrete parity symmetry breaking. In the critical region the MF solutions exhibit dynamical instability. The true many body state is a strongly correlated entangled state involving two macroscopically occupied modes (eigenstates of the single particle density operator). We characterize this state in various aspects: i) the eligibility for adiabatic evolution; ii) its analytical approximation given by the maximally entangled combination of two single modes; and finally iii) its appearance in particle detection measurements.Comment: 14 pages, 27 figure

La rentabilidad de la renovación de los equipamientos asociados al abastecimiento de agua en los edificios de la ciudad de Zaragoza

Producir energía degrada el medio ambiente, mejorar la eficiencia en su utilización constituye el modo menos costoso de preservar el entorno. El sector residencial presenta un potencial significativo de ahorro energético en su conjunto y, en particular, lo presentan las instalaciones de los edificios de distribución de agua a las viviendas. Sin embargo, sin un beneficio neto positivo no es de esperar que puedan llevarse a término las actuaciones necesarias para que los equipamientos mejoren en eficiencia, al margen del ahorro energético potencial que se obtenga. El trabajo analiza, por tanto, el impacto de las reformas de las instalaciones de suministro de agua a las viviendas en el consumo energético, así como su rentabilidad financiera y económica, tanto para una muestra representativa, como para el conjunto de la ciudad consolidada de Zaragoza. Los resultados muestran cómo obtener un beneficio neto positivo, a resultas de las reformas, dependerá de las características de la instalación, así como del edificio

Relationship between azithromycin susceptibility and administration efficacy for nontypeable Haemophilus influenzae respiratory infection

Nontypeable Haemophilus influenzae (NTHI) is an opportunistic pathogen that is an important cause of acute exacerbations of chronic obstructive pulmonary disease (AECOPD). COPD is an inflammatory disease of the airways, and exacerbations are acute inflammatory events superimposed on this background of chronic inflammation. Azithromycin (AZM) is a macrolide antibiotic with antibacterial and anti-inflammatory properties and a clinically proven potential for AECOPD prevention and management. Relationships between AZM efficacy and resistance by NTHI and between bactericidal and immunomodulatory effects on NTHI respiratory infection have not been addressed. In this study, we employed two pathogenic NTHI strains with different AZM sus- ceptibilities (NTHI 375 [AZM susceptible] and NTHI 353 [AZM resistant]) to evaluate the prophylactic and therapeutic effects of AZM on the NTHI-host interplay. At the cellular level, AZM was bactericidal toward intracellular NTHI inside alveolar and bronchial epithelia and alveolar macrophages, and it enhanced NTHI phagocytosis by the latter cell type. These effects correlated with the strain MIC of AZM and the antibiotic dose. Additionally, the effect of AZM on NTHI infection was assessed in a mouse model of pulmonary infection. AZM showed both preventive and therapeutic efficacies by lowering NTHI 375 bacterial counts in lungs and bronchoalveolar lavage fluid (BALF) and by reducing histopathological inflammatory lesions in the upper and lower airways of mice. Conversely, AZM did not reduce bacterial loads in animals infected with NTHI 353, in which case a milder anti- inflammatory effect was also observed. Together, the results of this work link the bactericidal and anti-inflammatory effects of AZM and frame the efficacy of this antibiotic against NTHI respiratory infection

Determination of a lectin protein allergen in food by on-line aptamer affinity solid-phase extraction capillary electrophoresis-mass spectrometry

An aptamer affinity sorbent was prepared for clean-up, preconcentration, separation and characterization of a food allergen protein by on-line aptamer affinity solid-phase extraction capillary electrophoresis-mass spectrometry (AA-SPE-CE-MS). SPE microcartridges were packed with a sorbent based on magnetic bead particles modified with an aptamer against the target lectin protein concanavalin A (Con A). After optimization of several parameters of the SPE-CE-MS method, the sample (ca. 30 µL) was loaded in separation background electrolyte (BGE, 2 M acetic acid pH 2.2), while the retained protein was eluted with 100 mM NH4OH (pH 11.2) (ca. 100 nL). The developed method was linear between 0.5 and 20 mg·L-1 and the limit of detection (LOD) was 0.25 mg·L-1, which was 100 times lower than by CE-MS. The repeatability of the method was satisfactory, with relative standard deviations (RSD) for migration times and peak areas below 1.9 and 8.1%, respectively. In addition, the microcartridges could be reused more than 25 analyses without significant loss of extraction efficiency. Finally, the applicability and versatility of the developed method were demonstrated by analyzing low levels of Con A in different food matrices (i.e. white beans, as well as chickpea, lentils, and wheat flours), leading to satisfactory results, with recoveries between 87 and 115%

Accurate determination of the milk protein allergen β-lactoglobulin by on-line aptamer affinity solid-phase extraction capillary electrophoresis-mass spectrometry

An on-line aptamer affinity solid-phase extraction capillary electrophoresis-mass spectrometry (AA-SPE-CE-MS) method was developed to purify, preconcentrate, separate, and characterize the milk allergenic protein β-lactoglobulin (β-LG) in food samples. The sorbent to pack into the SPE microcartidges was prepared by immobilizing an aptamer against β-LG onto magnetic bead particles. After optimizing the SPE-CE-MS method, the sample (ca. 75 µL) was loaded in separation background electrolyte (BGE, 2 M acetic acid pH 2.2), while a solution of 100 mM NH4OH (pH 11.2) (ca. 100 nL) was used for the protein elution. The linearity of the method ranged between 0.1 and 20 µg·mL-1 and the limit of detection (LOD) was 0.05 µg·mL-1, which was 200 times lower than by CE-MS. The method was repeatable in terms of relative standard deviation (RSD) for migration times and peak areas (< 0.5 % and 2.4 %, respectively) and microcartridge lifetime was more than 25 analyses. The applicability of the method for the determination of low levels of β-LG was shown by analyzing milk-free foods (i.e. a 100 % cocoa dark chocolate, a hypoallergenic formula for infants, and a dairy-free white bread) and milk-containing white breads. Results were satisfactory in all cases, thus demonstrating the great potential of the developed method for accurate food safety and quality control

Scissors mode of trapped dipolar gases

We study the scissors modes of dipolar boson and fermion gases trapped in a spherically symmetric potential. We use the harmonic oscillator states to solve the time-dependent Gross-Pitaevskii equation for bosons and the time-dependent Hartree-Fock equation for fermions. It is pointed out that the scissors modes of bosons and fermions can be of quite different nature

Microbes Should Be Central to Ecological Education and Outreach.

Our planet is changing rapidly, and responding to the ensuing environmental challenges will require an informed citizenry that can understand the inherent complexity of ecological systems. However, microorganisms are usually neglected in the narratives that we use to understand nature. Here, we advocate for the inclusion of microbial ecology across education levels and delineate the often neglected benefits of incorporating microbes into ecology curricula. We provide examples across education levels, from secondary school (by considering one's self as a microbial ecosystem), to higher education (by incorporating our knowledge of the global ecological role and medical application of microbes), to the general public (by engagement through citizen-science projects). The greater inclusion of microbes in ecological education and outreach will not only help us appreciate the natural world we are part of, but will ultimately aid in building a citizenry better prepared to make informed decisions on health and environmental policies