Photosynthetic acclimation of Nannochloropsis oculata investigated by multi-wavelength chlorophyll fluorescence analysis

Multi-wavelength chlorophyll fluorescence analysis was utilised to examine the photosynthetic efficiency of the biofuel-producing alga Nannochloropsis oculata, grown under two light regimes; low (LL) and high (HL) irradiance levels. Wavelength dependency was evident in the functional absorption cross-section of Photosystem II (σII(λ)), absolute electron transfer rates (ETR(II)), and non-photochemical quenching (NPQ) of chlorophyll fluorescence in both HL and LL cells. While σII(λ) was not significantly different between the two growth conditions, HL cells upregulated ETR(II) 1.6-1.8-fold compared to LL cells, most significantly in the wavelength range of 440-540nm. This indicates preferential utilisation of blue-green light, a highly relevant spectral region for visible light in algal pond conditions. Under these conditions, the HL cells accumulated saturated fatty acids, whereas polyunsaturated fatty acids were more abundant in LL cells. This knowledge is of importance for the use of N. oculata for fatty acid production in the biofuel industry. © 2014 Elsevier Ltd

The Effect of Diel Temperature and Light Cycles on the Growth of Nannochloropsis oculata in a Photobioreactor Matrix

A matrix of photobioreactors integrated with metabolic sensors was used to examine the combined impact of light and temperature variations on the growth and physiology of the biofuel candidate microalgal species Nannochloropsis oculata. The experiments were performed with algal cultures maintained at a constant 20u C versus a 15°C to 25°C diel temperature cycle, where light intensity also followed a diel cycle with a maximum irradiance of 1920 μmol photons m-2 s-1. No differences in algal growth (Chlorophyll a) were found between the two environmental regimes; however, the metabolic processes responded differently throughout the day to the change in environmental conditions. The variable temperature treatment resulted in greater damage to photosystem II due to the combined effect of strong light and high temperature. Cellular functions responded differently to conditions before midday as opposed to the afternoon, leading to strong hysteresis in dissolved oxygen concentration, quantum yield of photosystem II and net photosynthesis. Overnight metabolism performed differently, probably as a result of the temperature impact on respiration. Our photobioreactor matrix has produced novel insights into the physiological response of Nannochloropsis oculata to simulated environmental conditions. This information can be used to predict the effectiveness of deploying Nannochloropsis oculata in similar field conditions for commercial biofuel production. © 2014 Tamburic et al

KIMA: Noise: A visual sound installation on urban noise

KIMA: Noise is a participatory art piece inviting audiences to explore impact of urban noises interactively. Using specific urban sound sources, the audience experiences noise as spatial soundscapes, responding to it, physically engaging and interacting with it. KIMA: Noise creates awareness for the phenomenon of noise pollution. The paper looks at preeminent research in the field, and draws conclusions of how sound affects us as individuals. The art project KIMA: Noise is introduced technically and conceptually

Characterization and stability studies of emulsion systems containing pumice

Emulsions are the most common form of skin care products. However, these systems may exhibit some instability. Therefore, when developing emulsions for topical application it is interesting to verify whether they have suitable physical and mechanical characteristics and further assess their stability. The aim of this work was to study the stability of emulsion systems, which varied in the proportion of the emulsifying agent cetearyl alcohol (and) sodium lauryl sulfate (and) sodium cetearyl sulfate (LSX), the nature of the oily phase (decyl oleate, cyclomethicone or dimethicone) and the presence or absence of pumice (5% w/w). While maintaining the samples at room temperature, rheology studies, texture analysis and microscopic observation of formulations with and without pumice were performed. Samples were also submitted to an accelerated stability study by centrifugation and to a thermal stress test. Through the testing, it was found that the amount of emulsifying agent affects the consistency and textural properties such as firmness and adhesiveness. So, formulations containing LSX (5% w/w) and decyl oleate or dimethicone as oily phase had a better consistency and remained stable with time, so exhibited the best features to be used for skin care products

In Vivo Skin Performance of a Cationic Emulsion Base in Comparison with an Anionic System

Cosmetic science is a science-based, but fashion-led discipline. It covers a wide range of intersecting subjects, including biological sciences, dermatology, applied chemistry and physics. New raw materials for cosmetics and toiletries are continuously introduced into the competitive ingredients market. It is important that independent researchers perform strict, unbiased studies in order to assess their respective performance in the final products. This paper deals with a specific example of a relatively new class of emulsifying materials, the positively charged (cationic) emulsifiers. There are very few data regarding in-vivo skin performance of cationic emulsions against well-established non-ionic emulsifying systems, and no data regarding anionic/cationic comparison. The aim of this study was to perform a comparative assessment of the skin hydration potential of two emulsion creams: a cationic emulsion, based on distearyl dimethyl ammonium chloride, and an anionic emulsion, based on commonly used modified acrylic acid polymer. In addition, creams containing 5% herbal extracts (chamomile flower and blackthorn fruit, respectively) in each of the emulsion bases were also evaluated. A randomised in-vivo study was performed at the London College of Fashion, while the partners from the University of Belgrade have provided purposefully made and standardised plant extracts. The results showed significantly higher skin hydration obtained by the tested cationic emulsion, especially in the initial stages of the 3-hour trial. This finding backs-up the theoretical assumption of increased skin efficacy of cationic emulsions, because of their conditioning effect

Figaro-tresses: A dataset for evaluating hair assembly features before and after cosmetic treatment

The published database is composed of 1,080 images taken from 120 hair tresses made of medium blond, fine Caucasian hair with the aim to facilitate quantitative and qualitative studies about shampoo and conditioner efficacies. Two types of hair tresses were used: Caucasian hair which had not been subjected to oxidation with bleaching agents – virgin (60 tresses); and Caucasian hair, previously subjected to light oxidative bleaching – lightly bleached (remaining 60 tresses). Since cosmetic products such as shampoos and conditioners are often designed to subtly augment hair assembly features via the carefully balanced cumulative effects of deposited actives, each tress was subjected to consecutive washing+conditioning+drying cycles referred to as cosmetic treatment. The shampoo and conditioner used for this project were specifically selected for their suitability for fine hair. Each tress was photographed at three different time-points: before the cosmetic treatment; after two cosmetic treatments, and after an additional third cosmetic treatment. At each time-point, each tress was photographed from three different angles (−45, 0, and +45°), resulting in a total number of nine images for each tress. For each image in the database, we also provide a corresponding hair segmentation mask, which identifies the hair location area in the original image

The Effectiveness of Global Constructed Shallow Waterbody Design Guidelines to Limit Harmful Algal Blooms

Constructed shallow waterbodies are often designed and built to limit harmful algal blooms in urban regions. Efforts to reduce algal bloom occurrence in these waterbodies have largely focused on waterbody design, catchment criteria and onsite engineering options. However, many constructed shallow waterbodies that comply with design guidelines still experience harmful algal blooms. Identifying the knowledge gaps in current guidelines and examining their recommended design criteria can improve their effectiveness to reduce algal outbreaks. Here, we reviewed 66 global guidelines and identified common design criteria. The use of a ‘one size fits all' empirical approach and dated literature are common issues associated with the design criteria recommended. Further, only approximately one third of the guidelines that were analyzed directly mentioned harmful algal bloom-related design criteria. To test the validity of these design values in a real-world setting, the suitability of design factors in limiting harmful algal blooms was assessed by analyzing 222 shallow waterbodies monitored over a 9 year period in southeastern Australia. The site analysis indicated that macrophyte area to surface area ratio, shoreline development index, and fetch are the three most influential single design factors associated with harmful algal bloom reduction. The analyses highlighted the ineffectiveness of the existing design criteria globally, with blooms occurring even though some waterbodies were designed in accordance with recommended parameters. The analysis suggested that understanding interactions between multiple design factors may be a useful approach, for example, when considering the macrophyte area to surface area ratio in combination with the shoreline development index

Artificial intelligence and sensory assessment of hair assembly features: a combined approach

An explorative comparison of the sensitivity of human perception with that of classification algorithms for machine learning when applied to human hair tresses