bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation of Turkish and Italian Students’ Perceptions of the Concept of "Mathematics Teacher" through Metaphor Analysis
Authors: Peker Bilge
Published: October 2018

The main purpose of the present research is examining the Turkish and Italian students’ perceptions of the concept of"mathematics teacher" through metaphors. The study group of the research consists of 167 Turkish and 112 Italianstudents, the total of 279 students in the same age group. Students were asked to use another concept defining what“mathematics teacher” meant for them and to explain why. For this purpose, the data of the research were collectedby each student’s completing the statement "A mathematics teacher is like ..., because …." Content analysistechnique was used to analyze and interpret the obtained data. According to the findings of the research, the studentsdeveloped a total of 255 valid metaphors. These metaphors are divided into 9 different conceptual categoriesaccording to their common characteristics. According to the results of the analysis, Turkish students developedmetaphors on the didactic quality of mathematics teachers and Italian students developed metaphors aboutpersonality traits of mathematics teachers. Additionally, Turkish male students developed metaphors about the factthat mathematics teachers were their constant supporters. These findings are believed to have resulted from themathematics teaching styles of math teachers and the cultural factors.
The Development of Service Learning Management Model of Undergraduate Program in Private University
Authors: Soontorn Taneenart Na
Published: October 2018

The objectives of research are to develop, identify the main components of “Service Learning Management (SLM)”model, and to assess, evaluate the performance achievement of SLM implementation for undergraduate program inprivate university. The process of research is divided into two parts as: 1). developing the questionnaire samples thatwill be distributed to 377 lecturers in private university as the respondents for finding the appropriateness of maincomponents in SLM model by applying the Multi-Stage Sampling; and 2) testing and evaluating the SLM model’seffectiveness that will be executed to 11 students in Bachelor of Arts (Major: English for International Communication)of Saint John's University, who registered ENG. 3202 (Introduction to Speech Communication) as a subject insemester 2/2016. The research findings are described the SLM model that consists of 4 major variables and 9sub-variables as: 1) ‘Input’ has the 3 sub-variables (Integrated curriculum and instruction; learning outcomesdetermining; and resource management); 2) ‘Process’ includes 6 sub-variables that can be classified in to 5 steps(Investigation: lets the community set the requirement; Preparation: is the cooperation of three sides - university,student and community; Execution: is having positive relationship with community; Reflection: continuouslyevaluating; and Demonstration: is public relations and publicity; 3) ‘Output’ is the outcomes of learners and results ofthe evaluation; and 4) ‘Feedback’ is applying and integrating the outcomes of student’s accomplishment andevaluation. The results of demonstration and evaluation of SLM reflection to student performance achievementrevealed that 80 percent of students had higher GPA (Grade Point Average), and the learning outcome of studentsaccording to Thailand Qualifications Framework (TQF) is considered as high. The results of leadership competency,disciplinary and voluntariness of self-assessment test are counted as high in all aspects. Reflection record candevelopment critical thinking Finally, the overall satisfaction grading by university is considered as high in all aspects,and also the community responses have more advantage benefits and positive impacts in all aspects.
Landesrecht Thüringen
Authors: Baldus Manfred , Knauff Matthias
Published: October 2018

Für alle Studenten und in der Praxis Tätigen sind Kenntnisse des Landesrechts unabdingbar. Zu den Kernrechtsgebieten des Thüringer Landesrechts gibt es bislang keine Darstellung – diese Lücke schließt das Studienbuch. Es erörtert angefangen vom Landesverfassungsrecht über das allgemeine Verwaltungsrecht insbesondere das Polizei- und Ordnungsrecht, das Kommunalrecht sowie das Bau- und Umweltrecht. Mit den Ausführungen zum Haushaltsrecht ist das Werk gleichermaßen unabdingbare Arbeitshilfe für alle im Landesdienst tätigen Mitarbeiterinnen und Mitarbeiter. Die nicht nur studien-, sondern in hohem Maße praxisrelevanten Fragestellungen des öffentlichen Wirtschaftsrechts werden ebenfalls behandelt.
Prof. Dr. Manfred Baldus ist Inhaber der Professor für Öffentliches Recht und Neuere Rechtsgeschichte an der Universität Erfurt; seit 2008 ist er Mitglied des Thüringer Verfassungsgerichtshofs.
Prof. Dr. Matthias Knauff lehrt öffentliches Recht, insbesondere öffentliches Wirtschaftsrecht an der Friedrich-Schiller-Universität Jena; dort ist er u.a. geschäftsführender Direktor des Instituts für Energiewirtschaftsrecht.
Strafrecht Besonderer Teil II
Authors: Kindhäuser Urs , Böse Martin
Published: October 2018

Ziel des Buches ist die Vermittlung gründlicher Kenntnisse auf dem Gebiet des Vermögensstrafrechts. Der Schwerpunkt liegt in der Gesetzesauslegung. Historische und kriminologische Bezüge kommen nur zur Sprache, wenn dies für das Verständnis einer Norm oder eines Lehrsatzes unumgänglich erscheint. Die dogmatischen Teile sind knapp gehalten, wenn sich hinter einem Lehrsatz keine Streitfrage mit nennenswerten Konsequenzen für die Normanwendung verbirgt. Dagegen sind diejenigen Teile umfangreich erläutert, in denen mehr oder minder umstrittene Lehrsätze mit praktischen Auswirkungen dargestellt werden. Neben dem Pflichtstoff sind auch solche Delikte, die – wie z.B. die Insolvenzstraftaten – für den universitären Schwerpunktbereich im Strafrecht bedeutsam sein können, relativ ausführlich behandelt.
Für die 10. Auflage wurde das Lehrbuch durchgehend aktualisiert und überarbeitet. Herr Professor Martin Böse (Universität Bonn) ist in die Autorenschaft mit eingetreten.
Karp, M. (2016). This Vast Southern Empire: Slaveholders at the Helm of American Foreign Policy. Cambridge: Harvard University Press. 360 pages.
Authors: Caprice Kevin
Published: October 2018

En This Vast Southern Empire, Matthew Karp se aleja de la historiografía anterior de la esclavitud del Sur antes de la guerra, una historiografía que sitúa a los esclavistas como anticuados y mirando hacia adentro, y, en cambio, Karp ve una élite esclavista del sur mirando hacia afuera en un intento de consagrar su visión. de la modernidad: una economía mundial basada en el trabajo esclavo. Karp remata su estudio con la emancipación británica de las Indias Occidentales en 1833, vista por los sureños como una amenaza global a la proliferación de la esclavitud, y la creación y el fracaso final de los Estados Confederados de América, que Karp considera el “proyecto de política exterior más audaz todos ”(pág. 2). En esta nueva versión, Karp sostiene que, desde 1833 hasta 1861, las élites del sur utilizaron con entusiasmo el poder federal para garantizar la seguridad de la esclavitud, no solo en los Estados Unidos, sino en todo el hemisferio occidental.

In This Vast Southern Empire, Matthew Karp steps back from the previous historiography of the slaveholding antebellum South, a historiography that situates slaveholders as antiquated and inward looking, and, instead, Karp sees a slaveholding Southern elite looking outward in an attempt to enshrine their vision of modernity: a world economy run on slave labor. Karp bookends his study with the 1833 British emancipation of the West Indies, seen by Southerners as a global threat to the proliferation of slavery, and the creation and ultimate failure of the Confederate States of America, which Karp deems the “boldest foreign policy project of all” (p. 2). In this fresh take, Karp argues that, from 1833 to 1861, Southern elites eagerly utilized Federal power to secure the safety of slavery, not just in the United States, but throughout the Western Hemisphere.
La mujer como exemplum. Subversión, desafío y resistencia en Valerio Máximo.
Authors: González Estrada Lidia
Published: October 2018

En el presente texto tratamos de adentrarnos en la complejidad de la acción femenina que, representadas en obras como la de Valerio Máximo, basadas en la ejemplaridad, permite vislumbrar las distintas formas de proceder de las mujeres en la sociedad romana. En los casos que presentamos, no solo podemos ver más allá de los estereotipos, sino que también apreciamos a las mujeres rebelándose contra los roles de género y la moralidad que la sociedad les impone, ya sea como madres, esposas o ciudadanas.

The following article dives into the complexity of women’s actions represented in ancient accounts such as Valerius Maximus’. Through the inquiry of these works based on the Roman idea of exempla, it is intended to draw an extensive analysis of women’s role in the Roman society. In the studied cases, it is not only possible to see beyond the stereotypes but can also be noted the women’s rebellion against gender roles and the morality imposed by the society, either as mothers, wives or citizens.
Modelos de conciencia histórica en el alumnado de Educación Secundaria: tradición, simbología y contextualización en torno a los restos del franquismo.
Authors: Miguel-Revilla Diego , Sánchez Agustí María
Published: October 2018

El concepto de conciencia histórica, ligado con las concepciones del pasado y futuro en relación al presente, sirve como marco de análisis sobre las ideas del alumnado de Historia. La presente investigación ha contado con 132 estudiantes de cuarto curso de la ESO de cuatro ciudades españolas, con los que se ha trabajado en torno a la Transición española a través de un entorno digital de aprendizaje. Ante una problemática relacionada con la pervivencia de restos patrimoniales de la etapa franquista, y mediante un análisis cualitativo, el estudio centra su atención en caracterizar los modelos de conciencia histórica del alumnado. Los resultados identifican rasgos clave en sus concepciones, incluyendo la influencia de la tradición y una preocupación por la simbolización, corroborando además que la visión genealógica, ligada a la contextualización, es menos frecuente que las visiones tradicional, ejemplar y crítica.

The concept of historical consciousness, associated to past and future conceptions in relation to the present, is useful as an analytical framework focusing on history students’ ideas. This paper has counted on the participating of 132 fourth-year compulsory secondary education students from four different cities in Spain, who have worked about the Spanish transition to democracy with a digital learning environment. Using a controversial issue linked with the continuity of patrimonial remains of the Francoist era, and by means of a qualitative analysis, this study centers its attention in characterizing students’ historical consciousness models. The results help identify key characteristics in their conceptions, including the influence of tradition and a concern for symbolization, corroborating that the genetic vision, related to contextualization, is less common than the traditional, exemplary and critical ones.
La importancia de la contextualización curricular en la enseñanza de la Historia en México.
Authors: Bautista Rojas Enrique
Published: October 2018

El propósito de este trabajo es analizar la importancia de la contextualización curricular en la enseñanza de la historia en la escuela secundaria en México. Esto implica la generación de experiencias educativas que favorezcan el desarrollo del pensamiento histórico a partir de la construcción de aprendizajes significativos y situados que consideren las características de los estudiantes y su entorno. Se discute tomando referentes teóricos derivados del socioconstructivismo para criticar la forma en que tradicionalmente se ha enseñado la historia en este nivel educativo, lo que ha dado por resultado procesos poco relevantes en la vida escolar y cotidiana de las y los jóvenes. Al abordar este tema, se busca brindar pautas de reflexión y puntos para guiar el trabajo de los docentes y favorecer su compromiso hacia la formación de futuros ciudadanos críticos, informados y comprometidos con su sociedad

The intention of this paper is to analyze the importance of curricular contextualization in the history teaching in Mexican junior high school. This implies the generation of educational experiences that support the development of historical thinking through the construction of significant and situated learnings that consider the characteristics of students and their environment. The discussion takes references derived from the social constructivist theory and criticizes the traditional teaching of history in this educational level. This teaching method has resulted in unimportant processes in the school and daily life of young people. The work seeks to provide reflection guidelines and points to guide the teaching practice and promote its commitment to the formation of future critical, informed and committed citizens to their society
Experiencia didáctica para la enseñanza de la historia contemporánea a través de las fuentes en Educación Superior.
Authors: Llonch-Molina Nayra , Parisi-Moreno Verónica
Published: October 2018

El presente trabajo muestra una experiencia de innovación docente en didáctica de la historia. La experiencia se llevó a cabo en el Grado de Educación Primaria y se basó en el uso combinado de fuentes primarias y recursos digitales, con el objetivo de desarrollar un modelo alternativo de enseñanza-aprendizaje de la historia que fomentara competencias de pensamiento histórico. El estudio de caso realizado desvela que dicha experiencia de innovación docente permite que los maestros en formación inicial pongan en práctica contenidos conceptuales y procedimentales determinantes para la adquisición de contenidos y de metodologías de enseñanza-aprendizaje de las Ciencias Sociales y la Historia

This paper presents an experience of teaching innovation in didactics of history. The experience was carried out in initial teacher training and was based on the combined use of primary sources and digital resources, with the aim of developing an alternative teaching-learning model of history that fosters historical thinking competences. The work done by the participants evidences that the experience allows teachers in initial training to put into practice conceptual and procedural contents that are decisive for the acquisition of both contents and teaching-learning methodologies of the Social Sciences and History
Talking to James Baldwin: Alain Mabanckou’s Jimmy
Authors: Schwarz Bill
Published: October 2018

« 
Talking to James Baldwin
 »
explores the consequences of the intimacy which many readers experience when they read Baldwin’s prose. What are we to do when we confront this intimacy ? What ethical questions does this raise ? What is there in Baldwin’s writings which enables us to imagine productively the relations between the dead and the living ?
African and American Selves: « Contact Zones » in All Our Names by Dinaw Mengestu
Authors: Duboin Corinne
Published: October 2018

Ethiopian American writer Dinaw Mengestu’s third novel All Our Names (2014) is a double narrative that alternates between post-independence Uganda and post-Civil Rights America, thus offering a critique on both postcolonial Africa and multiracial America. It gives voice to both an African student who seeks refuge in the U.S. and to an American social worker, a white Midwesterner deep-rooted in her hometown. This essay examines how Mengestu constructs his two characters and weaves together their painful singular stories as parallel subjective first-person narratives that offer two different perspectives on Africanness and Blackness. It further analyzes how he uses their encounter (a secret interracial love affair) to point to the contrasts and similarities of their two separate worlds and thus expose the instability of identity and the sense of self that go beyond their differences and affect both characters.
L’évaluation stratégique : une démarche qui favorise la gestion démocratique des projets de territoire
Authors: Soldo Edina , Arnaud Charlène
Published: October 2018

Cette recherche vise à questionner les démarches évaluatives dans leur capacité à favoriser la gestion démocratique de projets de territoire. Deux conditions principales d’une telle gestion peuvent être identifiées. Elle poursuit des finalités démocratisantes et garantit dans le même temps, des processus décisionnels et modalités de gouvernance démocratisés (1). Face à la nécessité de développer des méthodes d’accompagnement à la mise en oeuvre de projets de territoire, l’évaluation stratégique apparaît comme une démarche opportune. Ses quatre caractéristiques essentielles : une temporalité « chemin faisant », des modalités de gouvernance pluralistes et participatives, une posture de recherche-action ainsi qu’un protocole méthodologique mixte original, favorisent en effet, l’enracinement démocratique de tels projets (2).
La construction de la légitimité des femmes entrepreneures : une approche transactionnelle1
Authors: Chasserio Stephanie , Pailot Philippe , Poroli Corinne
Published: October 2018

En s’appuyant sur la théorie de la transaction sociale, cet article propose une grille de lecture interprétative destinée à cerner le processus de construction du sentiment de légitimité des femmes entrepreneures. Sur la base d’une étude qualitative menée auprès de quarante et une chefs d’entreprise, nous montrerons dans quelle mesure ce sentiment est indissociable d’éléments de cadrage de leurs expériences relationnelles qui, loin d’être une réalité extérieure aux séquences interactionnelles, les incluent et forment, en quelque sorte, la toile de fond des situations transactionnelles.
Émergence de nouvelles pratiques managériales et vulnérabilité
Authors: Delassus Éric , Silva François
Published: October 2018

La notion de vulnérabilité issue des éthiques ducare, pourrait-elle trouver sa place dans une refondation de la pensée managériale ? Les nouvelles formes d’organisation du travail, qui valorisent plus les relations entre les personnes que les performances individuelles, pourraient intégrer cette notion pour faire émerger un management humaniste favorisant la confiance et la sollicitude. Une culture de la responsabilité remettant en cause une vision gestionnaire des relations humaines et prenant en compte de la singularité de chacun verrait alors le jour. L’autorité du manager, plus compréhensive envers autrui et soucieuse de le faire progresser, y trouverait une nouvelle légitimité.
A brief introduction to Open Data, Open Source Software and Collective Intelligence for environmental data creators and users
Authors: Hengl Tomislav , Wheeler Ichsani , MacMillan Robert A
Published: October 2018

Using the term "Open data" has become a bit of a fashion, but using it without clear specifications is misleading i.e. it can be considered just an empty phrase. Probably even worse is the term "Open Science" — can science be NOT open at all? Are we reinventing something that should be obvious from start? This guide tries to clarify some key aspects of Open Data, Open Source Software and Crowdsourcing using examples of projects and business. It aims at helping you understand and appreciate complexity of Open Data, Open Source software and Open Access publications. It was specifically written for producers and users of environmental data, however, the guide will likely be useful to any data producers and user.
Transcriptome analyses reveal anthocyanin biosynthesis in eggplants
Authors: Xiao Xi Ou , Lin Wen qiu , Li Ke , Feng Xue Feng , Jin Hui , Zou Hua feng
Published: October 2018

We obtained a white-peel eggplant (L6-5) by EMS mutation in our previous study, whose total anthocyanin content was significantly decreased as compared with that of wild-type (WT). To analyse the anthocyanin biosynthesis mechanism in eggplants, we analysed the eggplant peel by RNA-seq in this study. The transcript results revealed upregulation of 465 genes and downregulation of 525 genes in L6-5 as compared with the WT eggplant. A total of 11 anthocyanin biosynthesis structure genes were significantly downregulated in L6-5 as compared with that in WT. Meanwhile, on the basis of the RT-PCR results of four natural eggplant cultivars, the expression pattern of 11 anthocyanin biosynthesis structure genes was consistent with the anthocyanin content. Thus, we speculated the anthocyanin biosynthesis pathway in eggplant peel. The transcript and RT-PCR results suggested positive regulation of MYB1, MYB108 and TTG8 and negative regulation of bHLH36 in anthocyanin biosynthesis. This study enhanced our cumulative knowledge about anthocyanin biosynthesis in eggplant peels.
Isolation, identification and molecular phylogenetic analysis of Hyblaea puera Nucleopolyhedrovirus
Authors: Vijay Krishnan Saranya , TV Sajeev
Published: October 2018

Hyblaea puera (Lepidoptera: Hyblaeidae), is considered as a serious pest of teak in India and other tropical regions. It causes entire defoliation of teak trees and results in huge timber loss thereby decreasing forest productivity. Hyblaea puera Nucleopolyhedrovirus (HpNPV) is a baculovirus that has been employed in various parts of India as a bio-control agent against the pest H. puera. An unfeigned nucleopolyhedrovirus was isolated from the larvae of the moth, H. puera in Kerala, South India. Polh, lef-8, pif-2 gene sequences were amplified by PCR with degenerate primers and extracted for phylogenetic analysis. Hyblaea puera Nucleopolyhedrovirus appeared to be a distinct species of Group II NPV alphabaculovirus. Polyhedrin coding region was characterized by nucleotide sequence analysis. To date, Polyhedrin is the first isolated and characterized gene of HpNPV. It indicated the presence of ORF comprising 741 nucleotides which encode 246 amino acids with a predicted molecular mass of 28 KDa. Phylogeny based on three conserved baculovirus genes showed the highest homology of HpNPV to Helicoverpa armigera NPV. These findings were hardened by restriction endonuclease analysis, even though some differences in restriction pattern were observed. The current study will encourage future efforts to improve the efficacy of HpNPV against its natural host.
Effects of graded concentrations of supplemental selenium on selenium concentrations in tissues and prediction equations for estimating dietary selenium intake in pigs
Authors: Son Ah Reum , Jeong Jin-young , Park Kyu Ree , Kim Minseok , Lee Sung Dae , Yoo Ji-Hyock , Do Yoon-Jung , Reddy Kondreddy Eswar , Lee Hyun-Jeong
Published: October 2018

The experiment was conducted to determine the effects of graded dietary selenium (Se) on organ weight and Se concentrations in tissues and to develop equations for estimating dietary Se intake in pigs. Sixteen barrows (initial body weight = 30.0 ± 2.6) were allotted to four dietary treatments including graded Se supplementations with 0, 1, 5, and 50 mg/kg of diet. The experimental diets fed to the pigs for 30 d, and then the pigs were euthanized, and the organs, muscle, and urine samples were collected. The hair and blood samples of pigs were collected on d 15 and 30. Equations were developed for predicting daily Se intake using the Se concentration in plasma, hair, liver, kidneys, muscle, or urine. For graded dietary Se concentrations, linear and quadratic effects on the final body weight, weight and relative weight of liver and kidneys were not observed. The Se concentration in plasma, hair, liver, kidneys, muscle, and urine were linearly and quadratically increased as dietary Se concentration increased (P < 0.001). The dietary Se concentration was positively correlated with the Se concentrations in the plasma, organs, muscle, and urine (r > 0.81,P < 0.001). The equations for estimating dietary Se intake using the Se concentration in the plasma, hair, or organ as an independent variable were significant (P < 0.05). In conclusion, the dietary Se concentration was well reflected in the Se concentration in the plasma, hair, liver, kidneys, and urine. The Se concentration in the plasma, hair, liver, and kidneys can be used as an independent variable for estimating the Se intake.
Toward an integrated approach to crop production and pollination ecology through the application of remote sensing
Authors: Willcox Bryony K. , Robson Andrew J. , Howlett Brad G. , Rader Romina
Published: October 2018

Insect pollinators provide an essential ecosystem service by transferring pollen to crops and native vegetation. The extent to which pollinator communities vary both spatially and temporally has important implications for ecology, conservation and agricultural production. However, understanding the complex interactions that determine pollination service provisioning and production measures over space and time has remained a major challenge. Remote sensing technologies (RST), including satellite, airborne and ground based sensors, are effective tools for measuring the spatial and temporal variability of vegetation health, diversity and productivity within natural and modified systems. Yet while there are synergies between remote sensing science, pollination ecology and agricultural production, research communities have only recently begun to actively connect these research areas. Here, we review the utility of RST in advancing crop pollination research and highlight knowledge gaps and future research priorities. We found that RST are currently used across many different research fields to assess changes in plant health and production (agricultural production) and to monitor and evaluate changes in biodiversity across multiple landscape types (ecology and conservation). In crop pollination research, the use of RST are limited and largely restricted to quantifying remnant habitat use by pollinators by ascertaining the proportion of, and/or isolation from, a given land use type or local variable. Synchronization between research fields is essential to better understand the spatial and temporal variability in pollinator dependent crop production. RST enable these applications to be scaled across much larger areas than is possible with field-based methods and will facilitate large scale ecological changes to be detected and monitored. We advocate greater use of RST to better understand interactions between pollination, plant health and yield spatial variation in pollinator dependent crops. This more holistic approach is necessary for decision-makers to improve strategies toward managing multiple land use types and ecosystem services.
Addendum to 2‐Butoxyethanol (Ethylene glycol monobutyl ether) [BAT Value Documentation, 2016]
Authors: Göen T. , Rettenmeier A.W. , Drexler H. , Hartwig A. ,   MAK Commission
Published: October 2018

In 2015 the German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated the biological tolerance value at the work place (BAT value) for 2‐butoxyethanol (ethylene glycol monobutyl ether) [CAS No. 
111‐76‐2
], considering butoxyacetic acid in urine to characterise the internal exposure. The main systemic adverse effects of 2‐butoxyethanol are on the haematopoietic system (haemolytic effects), followed by possible teratogenic and testicular effects. 2‐Butoxyethanol was classified in category 4 for carcinogenic substances, which enables the evaluation of a health based exposure limit. It can easily pass through the skin, so biological monitoring is necessary for a valid individual risk assessment. A considerable part of the absorbed 2‐butoxyethanol is excreted in form of the glutamine conjugate of butoxyacetic acid,i.e. N‐butoxyacetyl glutamine. The relative amount of this conjugate in the total excretion of butoxyacetic acid varied considerably intra‐ and inter‐individually depending on the exposure levels and possibly on enzyme polymorphisms. On average half of the total butoxyacetic acid is excreted in the form of the glutamine conjugate (factor 2). Various studies indicate that at high exposure levels the capacity of the conjugate reaction is exceeded and lower conjugated amounts appear. Due to the high variability of conjugated amounts of the butoxyacetic acid and the limitation of conjugated amounts at high exposure levels the previous BAT value for free 2‐butoxyacetic acid is converted with a factor of 1.5 to the total amounts of 2‐butoxyacetic acid. Additionally, the impact of diuresis is considered by the relation to the creatinine concentration. Therefore, a BAT value for the total butoxyacetic acid excretion of 150 mg butoxyacetic acid (after hydrolysis)/g creatinine was established. Sampling should be performed at the end of exposure and shift, respectively, after several previous shifts. This BAT value applies also for combined exposure to 2‐butoxyethanol and 2‐butoxyethylacetate.
Addendum to 2‐Butoxyethylacetate (Ethylene glycol monobutyl ether acetate) [BAT Value Documentation, 2016]
Authors: Göen T. , Rettenmeier A.W. , Drexler H. , Hartwig A. ,   MAK Commission
Published: October 2018

In 2015 the German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated the biological tolerance value at the work place (BAT value) for 2‐butoxyethylacetate (ethylene glycol monobutyl ether acetate) [CAS No.
112‐07‐2
], considering butoxyacetic acid in urine to characterise the internal exposure.

Due to the high variability of conjugated amounts of the butoxyacetic acid and the limitation of conjugated amounts at high exposure levels the previous BAT value for free 2‐butoxyacetic acid is converted with a factor of 1.5. Additionally, the impact of diuresis is considered by the relation to the creatinine concentration. Therefore, a BAT value for the total butoxyacetic acid excretion of 150 mg butoxyacetic acid (after hydrolysis)/g creatinine was established. The sampling time is at the end of exposure/shift after several previous shifts.

As the effects of the two glycol ethers 2‐butoxyethyl acetate and 2‐butoxyethanol are largely the same in the human organism, the BAT value applies to both and for combined exposure. The two substances were discussed together in the addendum of 2‐butoxyethanol.
Addendum to Arsenic and Inorganic Arsenic Compounds (with the exception of arsine) [BAT Value Documentation, 2016]
Authors: Ochsmann E. , Göen T. , Michalke B. , Weistenhöfer W. , Klotz K. , Drexler H. , Hartwig A. ,   MAK Commission
Published: October 2018

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated the “Biologischer Arbeitsstoff‐Referenzwert” (BAR) as well as the exposure equivalents for carcinogenic substances (EKA) for arsenic and inorganic arsenic compounds (with the exception of arsenic hydride). Available publications are described in detail.

The quantification of the various arsenic species is essential to understand the hazardous potential of the arsenic compounds which differ highly in their toxicity. Therefore the BAR for the sum of different arsenic species is no longer valid. Considering published data from occupational not exposed persons, new BAR for the arsenic species of 0.5 µg/l urine for arsenic (+III), 0.5 µg/l urine for arsenic (+V), 2 µg/l urine for monomethylarsonic acid (MMA) and 10 µg/l urine for dimethylarsinic acid (DMA) were evaluated. The differentiation of arsenic species now allows for the estimation of the individual health risks taking into account special influences like seafood consumption. Sampling time is at the end of exposure or the end of the working shift and after long term exposure at the end of the working shift after several shifts.

Data of a correlation of arsenic in the air and the sum of the arsenic species in urine were considered for the evaluation of the exposure equivalents for carcinogenic substances. This correlation is in good accordance with the EKA correlation of arsenic trioxide, which is based on former studies in which also the urinary concentrations of the sum of As (+III), As (+V), MMA and DMA were measured. Sampling time is at the end of exposure or the end of the working shift and after long term exposure at the end of the working shift after several shifts.
Addendum to Dichloromethane [BAT Value Documentation, 2016]
Authors: Bolt H.M. , Weistenhöfer W. , Drexler H. , Hartwig A. ,   MAK Commission
Published: October 2018

In 2015 the German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated dichloromethane [CAS No. 
75‐09‐2
], considering dichloromethane in blood to characterize the internal exposure.

In a chamber study, 14 non‐smokers were exposed to different concentrations of dichloromethane. After exposure to the present MAK value of 50 ml dichloromethane/m³ without physical activity, a concentration of 0.3 mg dichloromethane/l blood was measured. Considering an increased intake due to elevated breathing volume during work, the exposure to 50 ml dichloromethane/m³ results in a blood concentration of 0.5 mg/l. Taking into account this study and the EKA correlation of 2001, a BAT value of 500 µg dichloromethane/l blood was evaluated. Sampling time is straight after exposure.
Lead and its compounds – Determination of δ‐aminolevulinic acid in urine by HPLC with fluorescence detection [Biomonitoring Methods, 2018]
Authors: Göen T. , Weißflog L. , Blaszkewicz M. , Baumhoer G. , Schettgen T. , Dewes P. , Hartwig A. ,   MAK Commission
Published: October 2018

The working group “Analyses in Biological Materials” of the Permanent Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area verified the presented biomonitoring method.

The method described hereinafter permits the determination ofδ‐aminolevulinic acid (ALA) in urine as a biological marker of effect to assess exposure to lead. An indicator of such exposure is the increased urinary excretion of ALA caused by lead‐induced inhibition of the enzymeδ‐aminolevulinic acid dehydratase. The determination of ALA in urine is based on a condensation reaction of ALA with formaldehyde and acetylacetone yielding a pyrrolizine derivate, which can be sensitively detected using fluorescence detection. 6‐Amino‐5‐oxohexanoic acid is used as an internal standard. Calibration standards are prepared in pooled urine and processed in the same way as the samples to be analysed.

The method was extensively validated and the reliability data were confirmed by two independent laboratories, which have established and cross‐checked the whole procedure.
Arsenic and arsenic compounds – Determination of arsenic species (As(III), As(V), monomethylarsonic acid, dimethylarsinic acid and arsenobetaine) in urine by HPLC‐ICP‐MS [Biomonitoring Methods, 2018]
Authors: Schramel P. , Michalke B. , Emons H. , Göen T. , Hartwig A. ,   MAK Commission
Published: October 2018

The working group “Analyses in Biological Materials” of the Permanent Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area verified the presented biomonitoring method.

The analytical method described hereinafter permits the simple and specific determination of the arsenic species arsenic (III) (As3+), arsenic (V) (As5+), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA) and arsenobetaine in urine. The limits of quantitation allow the quantification of the above‐mentioned arsenic species in both occupational and environmental medicine.

To this end, the arsenic species are separated by anion‐exchange high‐performance liquid chromatography (anion‐exchange HPLC) and detected by inductively coupled plasma mass spectrometry (ICP‐MS). Sample preparation is done by diluting the urine with water. Calibration is performed using either single or mixed standards of the different arsenic species or using the standard addition method.

The method was extensively validated and the reliability data were confirmed by an independent laboratory, which has established and cross‐checked the whole procedure.
Ethylbenzene [MAK Value Documentation, 2018]
Authors: Hartwig A. ,   MAK Commission
Published: October 2018

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated the maximum concentration at the workplace (MAK value) and the Pregnancy Risk Group of ethylbenzene [
100‐41‐4
].

Critical effect is the liver toxicity, which is observed as centrilobular hypertrophy and liver weight increase resulting from the induction of enzymes and proliferation of hepatocytes, in long‐term studies with rats and mice. In an oral 13‐week study a NOAEL of 75 mg/kg bodyweight and day for rats and a NOAEC of 75 ml/m
3
for liver cell proliferation in mice were established. Based on this data, a MAK value of 20 ml/m
3
had been set. This value is now reaffirmed even considering the increased respiratory volume at the workplace for the cell proliferation study (see List of MAK and BAT Values, Sections I b and I c). Since a systemic effect is critical, Peak Limitation Category II is retained and since it is not clear whether the effects are due to the metabolites or ethylbenzene the default factor of 2 is confirmed.

The NOAEC for developmental toxicity in rats is 500 ml/m³ and after considering the increased respiratory volume at the workplace the difference to the MAK value is sufficient. Therefore, damage to the embryo or foetus is unlikely when the MAK value is observed and ethylbenzene remains in Pregnancy Risk Group C.
Crotonaldehyde [MAK Value Documentation, 2018]
Authors: Hartwig A. ,   MAK Commission
Published: October 2018

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated the germ cell mutagenicity and carcinogenicity of crotonaldehyde [
4170‐30‐3
,
123‐73‐9
].

Crotonaldehyde is a highly reactive mutagenic and cytotoxic compound without metabolic activation.

An oral carcinogenicity study in male rats, with the liver as the only organ examined, provides at most only an indication of a carcinogenic potential. Crotonaldehyde remains assigned to Carcinogen Category 3B because of the still limited database.

Despite some methodical deficiencies, new in vivo studies with positive results for bone marrow and spermatocyte chromosomal aberrations as well as dominant lethal mutations in mice lead to a reclassification in Category 3A for Germ Cell Mutagens.
1‐Ethoxy‐2‐propyl acetate [MAK Value Documentation, 2018]
Authors: Hartwig A. ,   MAK Commission
Published: October 2018

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated the maximum concentration at the work place (MAK value), the Pregnancy Risk Group and absorption through the skin of 1‐ethoxy‐2‐propyl acetate [
54839‐24‐6
].

1‐Ethoxy‐2‐propyl acetate is weakly irritating to the skin and eyes of rabbits. The critical effect is CNS depression after repeated inhalative exposure with a NOAEC of 100 ml/m
3
in a 28‐day study with rats. Based on this, the maximum concentration at the work place (MAK value) for 1‐ethoxy‐2‐propyl acetate is set at 20 ml/m
3
(120 mg/m
3
). This value also protects against possible irritation, as local effects are not observed up to 1200 ml/m
3
in the 28‐day rat inhalation study.

Since the critical effect of 1‐ethoxy‐2‐propyl acetate is systemic, Peak Limitation Category II is retained. There are still no specific toxicokinetic data available, so that the default excursion factor of 2 is also retained.

There are no data on reproduction toxicity with 1‐ethoxy‐2‐propyl acetate available. 1‐Ethoxy‐2‐propyl acetate remains assigned to Pregnancy Risk Group C in analogy to 1‐ethoxy‐2‐propanol. On the basis of data with 1‐ethoxy‐2‐propanol and other glycol ether acetates, skin contact is expected to contribute significantly to systemic toxicity and 1‐ethoxy‐2‐propyl acetate is designated with “H”.
N,N
‐Dimethylethylamine [MAK Value Documentation, 2018]
Authors: Hartwig A. ,   MAK Commission
Published: October 2018

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has evaluated a momentary value of N,N‐dimethylethylamine [
598‐56‐1
].

Critical effects are vision disturbances and irritation of the eyes and the respiratory tract in exposed workers and volunteers. In a study in a foundry, these effects were caused by peak exposures of about 10 ml/m
3
. By analogy with cyclohexylamine, a momentary value of 5 ml/m
3
which must not be exceeded at any time is also established for N,N‐dimethylethylamine.
Ethanol [MAK Value Documentation, 2018]
Authors: Hartwig A. ,   MAK Commission
Published: October 2018

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated the maximum concentration at the work place (MAK value) and the Pregnancy Risk Group of ethanol [
64‐17‐5
].

Ethanol is produced endogenously. Uptake of greater amounts depresses the central nervous system and is carcinogenic especially for the liver. The former MAK value of 500 ml/m
3
was derived from a study in exposed subjects at rest. It was calculated that at 500 ml/m
3
the AUC (product of the blood ethanol concentration and time of exposure) was similar to the standard deviation of the lifetime AUC of endogenous ethanol. At 50 W physical activity, which corresponds to a respiratory volume of 10 m
3
per day, the blood concentration of ethanol is about twice as high as compared with that of subjects in rest. Therefore, taking into account the increased respiratory volume at the workplace (see List of MAK‐ and BAT Values, Sections I b and I c), the MAK value is now lowered to 200 ml/m
3
. Since a systemic effect is critical, Peak Limitation Category II is retained. As irritation was observed at 1900 ml/m
3
, the excursion factor is now set to 4.

After oral uptake, ethanol causes developmental toxicity. The lowest reported concentration of ethanol in the blood in pregnant rats causing effects in the F1‐generation was 300 mg/l with a NOAEC of 70 mg/l. In an inhalation study, the NOAEC for developmental neurotoxicity in rats was 10 000 ml/m
3
which according to a PBPK model corresponds to a concentration of ethanol in the blood of about 65 mg/l. These NOAEC are more than 10 times as high as the ethanol concentration of 1 mg/l in humans exposed to 200 ml/m
3
even considering the increased respiratory volume at the workplace. Therefore, ethanol remains assigned to Pregnancy Risk Group C.
1,3‐Dioxolane [MAK Value Documentation, 2018]
Authors: Hartwig A. ,   MAK Commission
Published: October 2018

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated the maximum concentration at the workplace (MAK value) and the Pregnancy Risk Group of 1,3‐dioxolane [
646‐06‐0
].

1,3‐Dioxolane causes a reduction in white blood cell count and in relative spleen weight at 1000 ml/m
3
and above in female rats after 13 weeks whole body inhalation. The NOAEC is 298 ml/m
3
. As the percentage of white blood cell count reduction is the same after four and 13 weeks, no decrease of the NOAEC after chronic exposure is expected. The former MAK value of 100 ml/m
3
was derived from the NOAEC. The MAK value is now lowered to 50 ml/m
3
which takes into account the increased respiratory volume at the workplace because the blood:air partition coefficient of 1,3‐dioxolane is > 5 (see List of MAK and BAT Values, Sections I b and I c). Since a systemic effect is critical, Peak Limitation Category II is retained. The default excursion factor of 2 is retained as well, as no half‐life in blood is known.

In a prenatal toxicity study in rats with gavage application, 1,3‐dioxolane results in reduced fetal body weights and gross external, soft tissue and skeletal malformations or variations at 1000 mg/kg body weight and day. The NOAEL for developmental toxicity is 500 mg/kg body weight and day. After toxicokinetic scaling this dose corresponds to a concentration of 875 mg/m
3
(285 ml/m
3
) at the workplace. The difference to the MAK value of 50 ml/m
3
is not sufficient. Therefore, the assignment to Pregnancy Risk Group B, for substances, for which damage to the embryo or foetus must be expected even when the MAK value is observed, is confirmed.
Distillates (petroleum), hydrotreated light [MAK Value Documentation, 2018]
Authors: Hartwig A. ,   MAK Commission
Published: October 2018

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated the maximum concentration at the workplace (MAK value) and the Pregnancy Risk Group of hydrotreated light petroleum distillates [
64742‐47‐8
].

Critical effect of the vapour phase of hydrotreated light petroleum distillates is CNS depression in exposed subjects. A MAK value of 50 ml/m
3
had been set taking into account the increased respiratory volume at the workplace as compared with volunteers at rest (see List of MAK and BAT Values, Sections I b and I c). For the aerosol phase the critical effect is considered to be the lung toxicity seen in rats and mice. A MAK value of 5 mg/m
3
had been set as the respirable fraction (R). This value is now reaffirmed even considering the increased respiratory volume at the workplace.

Hydrotreated light petroleum distillates had been classified in Pregnancy Risk Group C because the NOAEC for developmental toxicity in rats is 400 ml/m
3
, the highest concentration tested. There is no new data on developmental toxicity. This classification is retained even considering the increased respiratory volume at the workplace.
Benzoic acid and alkali benzoates [MAK Value Documentation, 2017]
Authors: Hartwig A. ,   MAK Commission
Published: October 2018

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated benzoic acid and alkali benzoates [65‐85‐0;532‐32‐1;582‐25‐2] to derive a maximum concentration at the workplace (MAK value), considering all toxicity endpoints. Available study reports and publications are described in detail.

Based on the NOAEC for lung toxicity of 12.6 mg/m3in a 4‐week inhalation study in rats, a MAK value of 0.5 mg/m3for the strongly irritating benzoic acid has been derived. Alkali benzoates are only slightly irritating. In consideration of the systemic NOAEC of 250 mg/m3in another 4‐week inhalation study in rats exposed to benzoic acid, a MAK value for alkali benzoates of 10 mg/m3(inhalable fraction), calculated as benzoate, has been derived. Benzoic acid and alkali benzoates are assigned to Peak Limitation Category II, because systemic effects are critical, and excursion factors of 2 for alkali benzoates and of 4 for benzoic acid are set.

In a developmental toxicity study with sodium benzoate in rats, foetotoxic effects were observed at 1850 mg/kg body weight and day. The NOAEL was 1340 mg/kg body weight and day. In mice, rabbits and hamsters, no developmental toxicity from sodium benzoate was detected in the foetuses of dams treated with up to 175, 250 or 300 mg/kg body weight and day, respectively. The differences between the NOAEL for rats, mice, rabbits and hamsters scaled to an inhalation concentration at the workplace and the MAK value are considered so large that damage to the embryo or foetus is unlikely when the MAK value is observed. Therefore, benzoic acid and alkali benzoates are classified in Pregnancy Risk Group C.

Benzoic acid and alkali benzoates are not regarded as genotoxic. Long‐term studies with sodium benzoate in rats and mice were of limited validity and do not point to a carcinogenic potential. Sensitization is not expected as benzoic acid and alkali benzoates are not contact sensitizers in animal studies. Immediate contact reactions observed in animals and humans are based on a non‐immunologic mechanism. Skin contact is expected to contribute significantly to the systemic toxicity. Therefore, benzoic acid and alkali benzoates are designated with an “H”.