The ecology of Dunaliella salina (Chlorophyceae, Volvocales): Effect of environmental conditions on aplanospore formation

The conditions leading to aplanospore formation in the green halophilic flagellate, Dunaliella salina (Dunal) Teodoresco, were studied using mixed cultures established from field collected samples. Aplanospore formation generally requires reduced salinity, (at salinities > 20% w/v NaCl aplanospores are rarely formed), nitrogen depletion and the presence of sulphate. Cool temperatures and short daylength may also promote spore formation, whereas pH and irradiance have no effect. Aplanospore formation takes place once the culture has reached stationary phase and, in such cultures, up to 36% of the total cells present can be aplanospores, although percentages of spores of less than 5% are most common. The only exceptions to this are high-phosphate cultures where aplanospore formation occurs early in the growth cycle and then ceases. However, not all cultures are competent to form aplanospores, and some mixed or unialgal cultures never formed aplanospores under conditions identical to those where aplanospore formation was observed in others. The factor(s) leading to competency are not known. Unlike free-living cells of D. salina, the aplanospores contain the ketocarotenoid, canthaxanthin

Maintenance spare parts planning and control : a framework for control and agenda for future research

This paper presents a framework for planning and control of the spare parts supply chain in organizations that use and maintain high-value capital assets. Decisions in the framework are decomposed hierarchically and interfaces are described. We provide relevant literature to aid decision making and identify open research topics. The framework can be used to increase the e??ciency, consistency and sustainability of decisions on how to plan and control a spare parts supply chain. Applicability of the framework in di??erent environments is investigated

Automatic nuclei segmentation in H&E stained breast cancer histopathology images

The introduction of fast digital slide scanners that provide whole slide images has led to a revival of interest in image analysis applications in pathology. Segmentation of cells and nuclei is an important first step towards automatic analysis of digitized microscopy images. We therefore developed an automated nuclei segmentation method that works with hematoxylin and eosin (H&E) stained breast cancer histopathology images, which represent regions of whole digital slides. The procedure can be divided into four main steps: 1) pre-processing with color unmixing and morphological operators, 2) marker-controlled watershed segmentation at multiple scales and with different markers, 3) post-processing for rejection of false regions and 4) merging of the results from multiple scales. The procedure was developed on a set of 21 breast cancer cases (subset A) and tested on a separate validation set of 18 cases (subset B). The evaluation was done in terms of both detection accuracy (sensitivity and positive predictive value) and segmentation accuracy (Dice coefficient). The mean estimated sensitivity for subset A was 0.875 (±0.092) and for subset B 0.853 (±0.077). The mean estimated positive predictive value was 0.904 (±0.075) and 0.886 (±0.069) for subsets A and B, respectively. For both subsets, the distribution of the Dice coefficients had a high peak around 0.9, with the vast majority of segmentations having values larger than 0.8. © 2013 Veta et al

Non-destructive survey of early Roman copper-alloy brooches using portable X-ray Fluorescence Spectrometry

This paper argues that portable X‐ray fluorescence spectrometry (pXRF) is a suitable elemental measurement technique to study the production of copper‐alloy artefacts. However, rather than try to imitate the accuracy and precision of laboratory techniques, it is more beneficial to deploy it in a survey role, one that attempts to model chronological and geographical changes within large quantities of artefacts. To achieve this, it was investigated to what extent corrosion and the issues surrounding surface measurements affect the potential of this type of research. Analyses on early Roman period brooches gathered in the Nijmegen region of the Netherlands were subsequently compared with published data. Roman Provinces, Middle Ages and Modern Perio

Vaccination with experimental feline immunodeficiency virus vaccines, based on autologous infected cells, elicits enhancement of homologous challenge infection

Cats were vaccinated with fixed autologous feline immunodeficiency virus (FIV)-infected cells in order to present viral proteins to the immune system of individual cats in an MHC-matched fashion. Upon vaccination, a humoral response against Gag was induced. Furthermore, virus-neutralizing antibodies were detected in a Crandell feline kidney cell-based neutralization assay, but not in a neutralization assay based on primary peripheral blood mononuclear cells. Despite the induction of these FIV-specific responses, vaccinated cats were not protected. Instead, accelerated virus replication was found, an observation similar to what previous experiments using other vaccine candidates have shown. Here, the results of the present study are discussed in the light of enhancement of lentivirus infections as a complicating factor in lentivirus vaccine development

Back to the future: from appendage development toward future human hair follicle neogenesis

Hair disorders such as alopecia and hirsutism often impact the social and psychological well-being of an individual. This also holds true for patients with severe burns who have lost their hair follicles (HFs). HFs stimulate proper wound healing and prevent scar formation; thus, HF research can benefit numerous patients. Although hair development and hair disorders are intensively studied, human HF development has not been fully elucidated. Research on human fetal material is often subject to restrictions, and thus development, disease, and wound healing studies remain largely dependent on time-consuming and costly animal studies. Although animal experiments have yielded considerable and useful information, it is increasingly recognized that significant differences exist between animal and human skin and that it is important to obtain meaningful human models. Human disease specific models could therefore play a key role in future therapy. To this end, hair organoids or hair-bearing skin-on-chip created from the patient's own cells can be used. To create such a complex 3D structure, knowledge of hair genesis, i.e., the early developmental process, is indispensable. Thus, uncovering the mechanisms underlying how HF progenitor cells within human fetal skin form hair buds and subsequently HFs is of interest. Organoid studies have shown that nearly all organs can be recapitulated as mini-organs by mimicking embryonic conditions and utilizing the relevant morphogens and extracellular matrix (ECM) proteins. Therefore, knowledge of the cellular and ECM proteins in the skin of human fetuses is critical to understand the evolution of epithelial tissues, including skin appendages. This review aims to provide an overview of our current understanding of the cellular changes occurring during human skin and HF development. We further discuss the potential implementation of this knowledge in establishing a human in vitro model of a full skin substitute containing hair follicles and the subsequent translation to clinical use.Thrombosis and Hemostasi

Wacana Kritis Berita Online Kasus Penyadapan Pembicaraan Telepon Elit Indonesia oleh Agen Rahasia Australia

News on online portal has advantages over news on conventional media in constructing reality and affecting the audiences. This research aims to analyze online text news about Indonesian\u27s political elites phone-tapping by Australian intelligence agency in Indonesian and Australian online news portal. This research uses text analyzing technique with interpretative explanation application. Data collection were done by observation on four online news portals, and then continued by data selection in the form of related news text. This news text is acquaired by using search engine in the internet. Collected data then being analyzed using Van Dijk Critical Discourse Analysis to apprehend the social discourses constructed by the online news portals, ideologies behind it, and the impact of those news publication on Indonesia-Australia diplomatic relationship. The results of this research indicates that there is a difference in discourses between Australia and Indonesia\u27s online news portal regarding the phone-tapping of Indonesia\u27s political elites by the Australian intelligence agency. Reality construction which is built by those news portals shows some differences, caused by disparities of press system and communication cultures between the two nations. Besides that, media ideologies also affects that phone-tapping publication. Those news publication in the process inflicts reaction on the people of the two nations, which affects the diplomatic relations between the two country