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Photoreception in Phytoplankton

In many species of phytoplankton, simple photoreceptors monitor ambient lighting. Photoreceptors provide a number of selective advantages including the ability to assess the time of day for circadian rhythms, seasonal changes, and the detection of excessive light intensities and harmful UV light. Photoreceptors also serve as depth gauges in the water column for behaviors such as diurnal vertical m

RIFM fragrance ingredient safety assessment, ethylene brassylate, CAS Registry Number 105-95-3

Summary: The use of this material under current conditions is supported by existing information. This material was evaluated for genotoxicity, repeated dose toxicity, developmental and reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, as well as environmental safety. Data show that this material is not genotoxic nor does it have skin sensitiza

Chimney sweeps in Sweden : a questionnaire-based assessment of long-term changes in work conditions, and current eye and airway symptoms

Objectives: To explore chimney sweeping work tasks, chimney sweeps’ use of protective equipment, and type of fuel used by clients, over time. Further, to assess work-relatedness of current eye and airway symptoms. Methods: In a cross-sectional study in 2011, male Swedish chimney sweeps (n = 483; age 21–69 years) answered a questionnaire about their occupational history and eye and airway symptoms.

The ultrastructure of a chemoreceptor organ in the head of copepod crustaceans

The ultrastructure of the paired nerves, previously called frontal organ or X-organ, in copepod crustaceans was investigated. These nerves, run- ning from the anterior margin of the brain to the frontal edge of the animals, are found to contain the dendrites of three types of morpho- logically different sensory neurons. The first unit consists of two dendrites (distinguished by their myelinization

Tailored perioperative antimicrobial prophylaxis in urological surgery : myth or reality?

PURPOSE OF THE REVIEW: The controversies surrounding perioperative antimicrobial prophylaxis (AMP) are about the use and especially misuse of antibiotics. The overall lack of evidence to facilitate a rational perioperative AMP policy in urological surgery and the postoperative infectious complications remain a challenge. Therefore, a basic tool to aid decision-making would be useful. A model based

RIFM fragrance ingredient safety assessment, 3,7-dimethyl-1,6-nonadien-3-ol, CAS Registry Number 10339-55-6

The use of this material under current conditions is supported by existing information. This material was evaluated for genotoxicity, repeated dose toxicity, developmental and reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, as well as environmental safety. Data from the suitable read across analog linalool (CAS # 78-70-6) show that this mate

Input, behaviour and distribution of multiple elements in abiotic matrices along a transect within the Okavango Delta, northern Botswana

Wetlands fed by rivers can be a sink for elements depending on elemental concentrations, wetland hydrology, geochemistry, vegetation and climate. In the case of the Okavango Delta, northern Botswana, the outflow discharge is a small fraction (2–5%) of the inflow. This has strong potential consequences for the Delta, as it strongly affects element cycling and storage within the Delta. We estimated

The role of regions for different forms of business organizations

The evidence for associations between area characteristics and entrepreneurship is fairly consistent in most studies. These studies, however, have disregarded the fact that the areas might be constructs that have no effect on the individual differences in entrepreneurship and, furthermore, have conflated entrepreneurship and sole proprietorship, disregarding the impact of area constructs on differ

The ultrastructure of the chromatophores of Crangon and Pandalus (Crustacea)

The ultrastructure of the chromatophores of two decapod crustaceans, Crangon crangon and Pandalus borealis, is investigated. The pigment appears macroscopically as small units, so-called chromatosomes. These contain separate chromatophores of different colors, and each color is composed of several chromatophores. Each chromatophore contains pigment granules, tubuli (ca. 210 Å), a network of cister

Brain and eyes of Zygentoma (Thysanura)

The brain, the compound eyes and the ocelli are described for some zygentomid species. Special interest has been focused on Tricholepidion gertschii, a newly discovered, primitive species. The brain morphology shows great similarities in the general shape and in details within the whole suborder. The compound eyes of Tricholepidion gertschii and Lepisma saccharina resemble each other closely. The

The Networked China Researcher: Challenges and Possibilities in the Social Media Age

The Internet, apart from being a fascinating field of study in its own right, has opened up new possibilities for scholars to get news, gather data, connect with informants, and in general stay updated on rapidly changing developments in Chinese society. Social media have added yet another dimension as it enables researchers to catch up with events and public debates as they unfold and get valuabl

Mediatization and cultural heritage: Plural voices and new platforms

Recent work on heritage and social media has highlighted how social media offer new possibilities for citizens to share memories, identities, local culture and heritage, and thus constitute a more participatory and democratic platform (Giaccardi 2012). Social media encourage and enable new forms of engagement and interpretations of the heritage through user-generated content, personal reflections,

The nauplius eye and frontal organs in decapoda (Crustacea)

The present investigation concerns the nauplius eye and frontal organs in decapod Crustaceans. Representatives from all groups of the Decapoda are included. Some of the more important results are abstracted.The nauplius eye in several families within the Eucyphidea is more complicated than generally believed. It consists of a nauplius eye s. s. with three cups and three sensory cells in each and t