Number density of turbulent vortices in the entire energy spectrum

In coalescence and break‐up modeling, vortex number density and size distributions of turbulent vortices are required to calculate the rate of interaction between continuous and dispersed phases. Existing number density models are only valid for the inertial subrange of the energy spectrum and no model of the vortex number density, valid for the entire energy spectrum, is available. The number density of the turbulent vortices were studied and modeled for the entire energy spectrum including the dissipative, inertial, and energy containing subranges. It was observed that the new number density model depends on vortex size, local turbulent kinetic energy, and dissipation rate. Moreover, the new number density model was validated by the number density distributions quantified in a turbulent pipe flow. The turbulent vortices of the pipe were identified and labeled using a vortex‐tracking algorithm that was developed recently by the authors. © 2014 The Authors AIChE Journal published by Wiley Periodicals, Inc. on behalf of American Institute of Chemical Engineers AIChE J, 60: 3989–3995, 2014     

Dynamic multicrop model to characterize impacts of pesticides in food

A new dynamic plant uptake model is presented to characterize health impacts of pesticides applied to food crops, based on a flexible set of interconnected compartments. We assess six crops covering a large fraction of the worldwide consumption. Model estimates correspond well with observed pesticide residues for 12 substance-crop combinations, showing residual errors between a factor 1.5 and 19. Human intake fractions, effect and characterization factors are provided for use in life cycle impact assessment for 726 substance-crop combinations and different application times. Intake fractions typically range from 10?2 to 10?? kg(intake) kg(applied)?1. Human health impacts vary up to 9 orders of magnitude between crops and 10 orders of magnitude between pesticides, stressing the importance of considering interactions between specific crop-environments and pesticides. Time between application and harvest, degradation half-life in plants and residence time in soil are driving the evolution of pesticide masses.We demonstrate that toxicity potentials can be reduced up to 99% by defining adequate pesticide substitutions. Overall, leafy vegetables only contribute to 2% of the vegetal consumption, but due to later application times and higher intake fractions may nevertheless lead to impacts comparable or even higher than via the larger amount of ingested cereals.     

Investigating performance, reliability and safety parameters of photovoltaic module inverter: Test results and compliances with the standards

Reliability, safety and quality requirements for a new type of photovoltaic module inverter have been identified and its performance has been evaluated for prototypes. The laboratory tests have to show whether the so-called second generation photovoltaic module inverter can comply with the expectations and where improvements are still necessary. Afterwards, the test results have been compared with the internationals standards.     

Imaging Mass Spectrometry of a Coral Microbe Interaction with Fungi

Fungal infections are increasing worldwide, including in the aquatic environment. Microbiota that coexist with marine life can provide protection against fungal infections by secretion of metabolites with antifungal properties. Our laboratory has developed mass spectrometric methodologies with the goal of improving our functional understanding of microbial metabolites and guiding the discovery process of anti-infective agents from natural sources. GA40, a Bacillus amyloliquefaciens strain isolated from an octocoral in Panama, displayed antifungal activity against various terrestrial and marine fungal strains. Using matrix-assisted laser desorption/ionization-imaging mass spectrometry (MALDI-IMS), the molecular species produced by this microbe were visualized in a side-by-side interaction with two representative fungal strains, Aspergillus fumigatus and Aspergillus niger. The visualization was performed directly on the agar without the need for extraction. By evaluating the spatial distributions, relative intensities and m/z values of GA40 secreted metabolites in the fungal interactions and singly grown control colonies, we obtained insight into the antifungal activity of secreted metabolites. Annotation of GA40 metabolites observed in MALDI-IMS was facilitated by MS/MS networking analysis, a mass spectrometric technique that clusters metabolites with similar MS/MS fragmentation patterns. This analysis established that the predominant GA40 metabolites belong to the iturin family. In a fungal inhibition assay of A. fumigatus, the GA40 iturin metabolites were found to be responsible for the antifungal properties of this Bacillus strain.     

Femtosecond Chemical Dynamics in Solution: Photodissociation of I3-

We report a study of the UV photolysis of I₃⁻ in alcohol solutions, using femtosecond time-resolved transient transmission experiments. We interpret our results to indicate that photoexcitation leads to direct formation, within 300 fs, of diiodide ions which are vibrating coherently. The time scales for vibrational dephasing, vibrational relaxation, and reorientation of the fragment ions are 400 fs, 4 ps, and 5 ps, respectively. UV transient transmission experiments were conducted in order to characterize the time scales for recombination. Recombination takes place on several time scales. A fast component is assigned to primary recombination, followed by vibrational relaxation on the ground state of I₃⁻. The prominence of this recombination route is found to be strongly dependent on the solvent. Finally, time domain quantum simulation techniques are employed in order to gain insight into the nature of the nascent diiodide vibrational distribution, and to introduce a semiquantitative model for the stage of bond fission for isolated ions.     

Community Neighbourhood Park (CNP) Use in Cape Town’s Townships

Living sustainably entails fulfilling Maslow??s hierarchy of needs. The need for leisure and recreation is one of the most essential higher-order needs, and local authorities can meet these needs through park delivery. The existing park literature in South Africa is limited in scope and dates back to the apartheid era, with little evidence pertaining to community neighbourhood park (CNP) use in townships. The aim of this paper is to determine the perceptions, preferences, needs and uses of CNPs in five black townships in Cape Town. Findings indicate that townships have few CNPs, which therefore require travelling greater distances by public transport for access. Due to a lack of private garden space, respondents visit CNPs regularly and spend more time there, participating in either active or passive recreation. The main concerns about CNPs include safety and maintenance, and a lack of CNP facilities. These concerns extend to the type of facilities that respondents want to develop in CNPs, to create their ideal setting.     

Attributions, vulnerability, and psychological adjustment: The case of breast cancer.

Hypothesized that psychological adjustment would be positively associated with breast cancer victims' perceptions of invulnerability to a recurrence of cancer and that victims' causal attributions for cancer (e.g., self-blame, birth control pills, sexually demanding husband) would influence adjustment to the extent that the attributions contributed to or detracted from perceived invulnerability. A path model was developed based on the proposed association between invulnerability and adjustment, and attributions were tested for whether they directly or indirectly influenced adjustment. Responses from intensive interviews of 42 breast cancer victims (aged 23–81 yrs) who had undergone mastectomies within 2 yrs prior to being interviewed were used to test the path model. Ss were also administered the Beck Depression Inventory and another measure to assess emotional response to breast cancer at Ss' present stage of adjustment. Results support the hypothesized positive association between perceived invulnerability and adjustment and show that the relationships between specific attributions and adjustment were mediated by vulnerability beliefs. Follow-up data may be useful in ascertaining the role played by cognitions in the biological progression of cancer. (52 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Factorial validity of problematic Internet use scales

There exists a number of multidimensional measurement scales for problematic Internet use (PIU) with varying factor structures. This study reviews the factor analytic techniques used to develop these measures and discusses their implications for the factorial validity, particularly discriminant validity, of these PIU scales. To further illustrate these points, we reformulate the four-factor Online Cognition Scale into a more parsimonious two-factor measure (i.e., dependency and distraction) and demonstrate its factorial validity as well as robustness across student and working adult samples. Contributions of this research are discussed.