Technique of the Modulated Chlorophyll Fluorescence: Basic Concepts,Useful Parameters,and Some Applications

The review summarizes basic information about slow and fast chlorophyll (Chl) a fluorescence induction kinetics (FIK) recorded using fluorimeters working on a principle of the pulse amplitude modulation (PAM) of a Chl fluorescence signal. It explains fundamental principles of the measuring technique, evaluates the terminology, symbols, and parameters used. Analysis of Chl FIK resulting in a set of Chl fluorescence parameters (FPs) provides qualitative and quantitative information about photosynthetic processes in chloroplasts. Using FPs, one can describe the functioning of the photosynthetic apparatus under different internal and external conditions. Brief comments on proper application of the fluorimetric method in photosynthesis research and some actual examples are also given. This revised version was published online in June 2006 with corrections to the Cover Date.     

The Stone Brusher, a New Sampler for Submerged Epilithic Material in Shallow Streams and Lakes

The Stone Brusher is designed to take qualitative or semi-quantitative samples of material attached to stones at 7–50 cm depth in running or stagnant waters. The epilithic material is dislodged from the stone surface with a rotating brush enclosed in a chamber and the material is drawn up directly into the sample bottle with an air-cylinder. The operator takes a sample quickly and without putting hands into the water. The sampling area is about 28 cm². The sampler is made of plastic, stainless steel and aluminium and weighs 3.1 kg. The equipment is robust and easily handled and it is constructed to meet the demand for standardized sampling for research and environmental monitoring and to improve working conditions for sampling personnel. The equipment allows sampling from bedrock and large stones that cannot be lifted from the bottom and it can be used for reliable sampling also in fast-flowing streams where the dislodged material is easily flushed away. Using Near-Infrared Spectroscopy and diatom analyses, this new sampler is evaluated in comparison to the recognized toothbrush method, which indicates that the Stone Brusher reduces sampling variability compared with the toothbrush method.     

Imperfect detection and the determination of environmental flows for fish: challenges,implications and solutions

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Enriching Our Views on Clinical Ethics: Results of a Qualitative Study of the Moral Psychology of Healthcare Ethics Committee Members

The contribution of healthcare ethics committee (HEC) members to HECs is fundamental. However, little is known about how HEC members view clinical ethics. We report results from a qualitative study of the moral psychology of HEC members. We found that contrary to the existing Kohlberg-based studies, HEC members hold a pragmatic non-expert view of clinical ethics based mainly on respect for persons and a commitment to the patient’s good. In general, HEC members hold deflationary views regarding moral theory. Ethical principles are not abstract foundations but the expression of moral commitments to patients that pre-exist awareness of moral theory. Emotions and proximity to patient sufferance fundamentally shape the views of HEC members on clinical ethics. Further work at the intersection of clinical ethics and qualitative research could bring to the foreground lay perspectives on moral problems that may differ from bioethics expert views.     

National numbers for transnational relations? Challenges of integrating quantitative methods into research on transnational labour market relations

Abstract

Research into transnational labour markets requires qualitative as well as quantitative research data. Yet there is little discussion on how to integrate quantitative methods into existing – overwhelmingly qualitative?– approaches to transnational research. This article seeks to identify some of the key challenges for the use of quantitative methods in research on transnational social relations. Selected problems regarding (1) sampling procedures and (2) questionnaire design are discussed using examples from emergent transnational labour markets in the Central European region, arguing that a transnational perspective necessitates a mixed-methods design. The ethnosurvey is identified as a starting point for an appropriate research design. Multi-sited ethnography and respondent-driven sampling methods are discussed as crucial complementing elements of transnational mixed-methods research.     

Dynamic models of behavior: An extension of life history theory

Life history theory and behavioral ecology, two branches in the study of adaptation, have relied extensively on mathematical models, but have tended to employ different types of models, and different currencies of fitness. Recently, a new approach based on dynamic, state variable models has been increasingly applied to the study of behavioral adaptations. In fact, this approach amounts to a unification of life history theory and behavioral ecology, to the extent that the line separating the two fields is virtually obliterated. Dynamic models (usually solved by computer) can yield both general principles and testable, quantitative or qualitative predictions about specific behavioral and life history phenomena.     

Narkosefreie Blutabnahme und Labordiagnostik bei Großen Ameisenbären (Myrmecophaga tridactyla Linné, 1758) im Zoo Dortmund

Because of their very large claws, Giant anteaters are quite dangerous animals. In this study the principles of Medical Training with Giant anteaters were worked out in order to obtain information about organ health and physical development of the animals without fixation. Anesthesia-free blood sampling was performed upon three trained animals, taken from the medial saphenous vein. In most cases, this vein could be palpated only, or the blood sampling had to be done “blind”. From 23 obtained blood samples the organ parameters, hemogram, taurine and coagulation parameters were determined.     

Social Media,Public Participation,and the 2010 BP Deepwater Horizon Oil Spill

This research examines how information about an oil spill, its impacts, and the use of dispersants to treat the oil, moved through social media and the surrounding Internet during the 2010 BP Deepwater Horizon oil spill. Using a collection of tweets captured during the spill, we employ a mixed-method approach including an in-depth qualitative analysis to examine the content of Twitter posts, the connections that Twitter users made with each other, and the links between Twitter content and the surrounding Internet. This article offers a range of findings to help practitioners and others understand how social media is used by a variety of different actors during a slow-moving, long-term, environmental disaster. We enumerate some of the most salient themes in the Twitter data, noting that concerns about health impacts were more likely to be communicated in tweets about dispersant use, than in the larger conversation. We describe the accounts and behaviors of highly retweeted Twitter users, noting how locals helped to shape the network and the conversation. Importantly, our results show the online crowd wanting to participate in and contribute to response efforts, a finding with implications for future oil spill response.     

The gastropod Phorcus sauciatus (Koch, 1845) along the north-west Iberian Peninsula: filling historical gaps

The intertidal gastropod Phorcus sauciatus is a subtropical grazer that reaches its northern boundary in the Iberian Peninsula. Distribution of P. sauciatus along the Iberian Peninsula shows, however, gaps in its distribution. The present study was aimed at detecting possible recent changes on the population structure and distribution of P. sauciatus along the north-west Atlantic coast of the Iberian Peninsula. To achieve this aim, we adopted a qualitative sampling design to explore the presence of P. sauciatus along a region within its historical gap of distribution (north Portuguese coast). In addition, a quantitative sampling design was adopted to test hypotheses about the abundance and size structure of P. sauciatus populations among regions with different historical records of its abundance and among shores with different exposure. Results showed that P. sauciatus was present along the north Portuguese coast. However, the abundance and size structure of the newly settled populations were significantly different to those of the historically recorded populations. Moreover, P. sauciatus was able to establish populations at sheltered shores. Considering these results, we propose models for the distribution of P. sauciatus along the Iberian Peninsula, based on effects of sea surface temperature, and to explain the size-frequency of their populations based on their density.     

Neurodynamics, tonality, and the auditory brainstem response

Tonal relationships are foundational in music, providing the basis upon which musical structures, such as melodies, are constructed and perceived. A recent dynamic theory of musical tonality predicts that networks of auditory neurons resonate nonlinearly to musical stimuli. Nonlinear resonance leads to stability and attraction relationships among neural frequencies, and these neural dynamics give rise to the perception of relationships among tones that we collectively refer to as tonal cognition. Because this model describes the dynamics of neural populations, it makes specific predictions about human auditory neurophysiology. Here, we show how predictions about the auditory brainstem response (ABR) are derived from the model. To illustrate, we derive a prediction about population responses to musical intervals that has been observed in the human brainstem. Our modeled ABR shows qualitative agreement with important features of the human ABR. This provides a source of evidence that fundamental principles of auditory neurodynamics might underlie the perception of tonal relationships, and forces reevaluation of the role of learning and enculturation in tonal cognition.     

Assessing familial aggregation of age at onset, by using estimating equations, with application to breast cancer.

In genetic research of chronic diseases, age-at-onset outcomes within families are often correlated. The nature of correlation of age-at-onset outcomes is indicative of common genetic and/or shared environmental risk factors among family members. Understanding patterns of such correlation may shed light on the disease etiology and, hence, is an important step to take prior to further searching for the responsible genes via segregation and linkage studies. Age-at-onset outcomes are different from those familiar quantitative or qualitative traits for which many statistical methods have been developed. In comparison with the quantitative traits, age-at-onset outcomes are often censored, i.e., instead of actual age-at-onset outcomes, only the current ages or ages at death are observed. They are also different from qualitative traits because of their continuity. Because of the complexity of correlated censored outcomes, few methods have yet been developed. A traditional approach is to impose a parametric joint distribution for the correlated age-at-onset outcomes, which has been criticized for requiring a stringent assumption about the entire distribution of age at onset. The purpose of this paper is to describe a method for assessing familial aggregation of correlated age-at-onset outcomes semiparametrically, by use of estimating equations. This method does not require any parametric assumption for modeling the age at onset. The estimates of parameters, including those quantifying the correlation within families, are consistent and have an asymptotic normal distribution that can be used to make inferences. To illustrate this new method, we analyzed two age-at-onset data sets that were obtained from studies conducted in the States of Washington and Hawaii, with the objective of quantifying the familial aggregations of age at onset of breast cancer.     

Sampling of working-zone air and biomaterials and unification of MPC values

Some points concerning the strategy of working-zone-air sampling, the sampling plan and the manner of sampling biological materials have been discussed. In drawing up an air-sampling plan, the following items should be paid attention to: production technology, organization, physicochemical properties and composition of the raw materials, intermediate and final products, potential sources of spread of harmful substances and their spread from these sources, the time picture of workers' presence, the analytical method and the concentration of the harmful substances in the working-zone atmosphere. In order to unify MPC's within the frame of CMEA, one should be informed about the norms and standardized methods in force in each country, work out and unify principles for sampling the air and biomaterials and work out a project of a unified way of evaluating analysis results.     

“Why throw away something useful?”: Attitudes and opinions of people treated for bipolar disorder and their relatives on organ and tissue donation

In regard to mental illness, brain donation is essential for the biological investigation of central pathology. Nevertheless, little is known about the thoughts of people with mental disorders on tissue donation for research. Here, our objective was to understand the attitudes and opinions of people treated for bipolar disorder and their relatives regarding donation in general, and particularly donation for research. This is a qualitative study that used in-depth interviews to determine the thoughts of participants regarding tissue donation for research. Theoretical sampling was used as a recruitment method. Grounded theory was used as a framework for content analyses of the interviews. A semi-structured interview guide was applied with the topics: donation in general; donation for research; mental health and body organs; opinion regarding donation; feelings aroused by the topic. Although all participants were aware of organ donation for transplant, they were surprised that tissue could be donated for research. Nevertheless, once they understood the concept they were usually in favor of the idea. Although participants demonstrated a general lack of knowledge on donation for research, they were willing to learn more and viewed it as a good thing, with altruistic reasons often cited as a motive for donation. We speculate that bridging this knowledge gap may be a fundamental step towards a more ethical postmortem tissue donation process.     

实验鼠群的健康监测管理

虽然实验鼠种群的总体健康水平得到了显著的提高,但还是有很多重要的传染性病原体在实验鼠群中流行.实验鼠群的健康状况对于动物福利、科学研究甚或人类健康都很重要.所以必须要对实验鼠群进行健康监测.笔者依据自身的实践和经验,对鼠群健康监测的基本原理进行了分析,包括以下的内容：鼠群健康监测的必要性、健康检测规程的建立、哨兵鼠、常用的监测力法、样本采集原则、对检测结果的解读和应对.相信读者在了解这些基本的原理后,能设定出符合自身设施实际的鼠群健康监测计划并逐步在实践中完善.     

景观指数分类、应用及构建研究

在景观生态学研究中,理解与把握景观格局变化的生态学原则至关重要,用景观指数描述景观格局及变化,建立格局与景观过程之间的联系,是景观生态学最常用的定量化研究方法,本文在综合前人对景观指数的基础上,对景观指数研究从景观指数的分类研究,指数对景观格局的描述研究,指数之间的相关性研究及指数构建研究等4方面进行了总结,并从单个景观指数与指数体系两个层次上提出了判定景观指数优劣及景观指数应用的一般性原则。     

Linking the conventional and emerging detection techniques for ambient bioaerosols: a review

Bioaerosols are biologically originated particles present in the atmosphere that can be formed from any process involving biological materials. They comprise of both living and non-living components including organisms, dispersal methods of organisms, and excretions. Bioaerosols such as airborne bacteria, fungal spores, pollen, and others possess diverse characteristics and effects. A large gap exists in the scientific understanding of the overall physical characteristics and measurement of bioaerosols. Consequently, this review aims to devise an appropriate approach to generate more scientific knowledge of bioaerosols. In addition to comparisons and discussions about the various factors affecting bioaerosols, sampling, handling, and the application of various devised analytical techniques, this review offers insight into the current state of bioaerosol research. The review focuses on instrumental and methodical strategies to understand bioaerosol measurement. Numerous studies have investigated conventional methods, advanced methods, and real-time methods that can be applied for bioaerosol monitoring. Each method is different in terms of working principle, characteristics, sensitivity, and efficiency. For the first time, this review explains and compares different methods of conventional, offline, online, and real-time detection methods of bioaerosols based on their working principles, sensitivity, and efficiency on a single platform. This will provide a clear concept and better options for selecting the appropriate method based on the research proposal. Furthermore, recent advances are summarized, and future outlooks are emphasized for bioaerosol identification and categorization. This study also encourages developing affordable and standardized methods to avoid the inter-laboratory and sampling variability to obtain a better understanding and comparison of bioaerosol measurements worldwide. Nevertheless, this work can assist researchers in selecting appropriate methods for bioaerosol measurement and investigation.

     

Evaluating Diversification Hypotheses in the South American Cricetid <Emphasis Type="Italic">Thaptomys nigrita</Emphasis> (Lichtenstein, 1829) (Rodentia: Sigmodontinae): An Appraisal of Geographical Variation Based on Different Character Systems

Molecular surveys using mtDNA sequences have been used to identify cryptic species in sigmodontine rodents. However, where sampling is uneven, a critical appraisal of further evidence is pivotal to test whether genetic discontinuity represents different species. In order to investigate geographical variation in the Neotropical rodent Thaptomys nigrita, we analyzed patterns of morphological variation in qualitative and morphometric data, and compared our results with recent information on karyological and molecular diversity reported for the monotypic genus. Two subtle morphometric groups of populations, corresponding to karyomorphs 2n = 50 and 2n = 52, were revealed, but no qualitative aspect of craniodental morphology unambiguously distinguished them. A positive and significant association between geographical and both morphological and genetic distances suggest that the distinction between the two groups of population follows an isolation by distance model. This result, coupled with phylogeographic and karyotypic breaks coincident to a sampling gap extending for 540 km, and with the low phylogenetic resolution of molecular clades, does not allow rejecting the hypothesis that the divergent samples constitute polymorphic populations of a widely distributed species. We discuss possible determinants of these patterns and emphasize the need for an integrative approach in future efforts to disclose the evolutionary relationships of small mammals in situations of uneven sampling.