bluuebunny/crossref_metadata_2025 huggingface dataset:
„Vereinfachte Unternehmenssteuer“? — Analyse des Berichts der Expertenkommission vom 12.7.2024 an den BMF
Authors: Lishaut Ingo van
Published: September 2024

Der Verfasser kommentiert den Bericht der von Bundesfinanzminister Lindner eingesetzten Kommission zur Vereinfachung des Unternehmenssteuerrechts teils befürwortend, teils ablehnend, und stellt eigene, ergänzende Überlegungen an. Im Herbst 2023 hatte Bundesfinanzminister Lindner eine Expertenkommission berufen, die aus sieben Hochschullehrern und sechs Vertretern von Großunternehmen bestand und unter der Leitung von Professor Dr. Dr. h.c. Wolfgang Schön aus München getagt hat; anders als bei früheren Reformkommissionen waren keine Vertreter aus der Finanzverwaltung oder aus der Richterschaft beteiligt. Die Kommission hat unter dem 12.7.2024 ihren Abschlussbericht vorgelegt, der 222 Seiten umfasst und sich in die Bereiche - Laufende Unternehmensbesteuerung, - Umwandlungen und Sanierungen, - Internationale Unternehmensbesteuerung - sowie Digitalisierung, Prozesse und Betriebsprüfung gliedert. Erklärtes Ziel ist die Entlastung der Unternehmen von überflüssiger Bürokratie und von ineffizienten, ökonomische Entscheidungen behindernden Besteuerungsregeln. Die Kommission verzichtet auf Schätzungen zu den Aufkommenswirkungen ihrer Reformvorschläge (Tz. 2.3.11 des Berichts), was Umsetzungsentscheidungen natürlich massiv erschwert. Nachfolgend wird die Zusammenfassung des Kommissionsberichts (Tz. 7 des Berichts) wiedergegeben und soweit möglich und nötig mit Anmerkungen versehen. Der wiedergegebene Text ist kursiv gesetzt. Soweit in den Anmerkungen auf Textziffern Bezug genommen wird, handelt es sich um die der Langfassung des Berichts.
Die Verfassungsmäßigkeit der Besteuerung der Energiepreispauschalen I und II und Überlegungen zu Gestaltungsmöglichkeiten zukünftiger (steuerlicher) Transferzahlungen – Teil 1
Authors: Hübner Hendrik , Letzner Steven
Published: September 2024

Im vorliegenden ersten Teil des Beitrags untersuchen die Verfasser die Frage der Verfassungsmäßigkeit der Besteuerung der Energiepreispauschalen I und II. Im anschließenden zweiten Teil des Beitrags werden dann Überlegungen zu Gestaltungsmöglichkeiten zukünftiger (steuerlicher) Transferzahlungen angestellt, um prüfen zu können, ob durch diese den mit beiden Energiepreispauschalen verfolgten gesetzgeberischen Zielen besser hätte Rechnung getragen werden können als durch die gewählten Ausgestaltungen.
Die geplante Stiftung Generationenkapital zur langfristigen Rentenniveausicherung – rechtliche Herausforderungen bei der kapitalgedeckten Finanzierung ihr übertragener Aufgaben
Authors: Dettmeier Michael , Bell Miriam le , Paraschiakos Christos
Published: September 2024

Die Verfasser beleuchten den Gesetzesentwurf der Bundesregierung zur Errichtung einer Stiftung Generationenkapital. Auch wenn sich die Bundesregierung am Vorbild des „Fonds zur Finanzierung der kerntechnischen Entsorgung“ (KENFO) orientiert, um in die teilweise Kapitaldeckung der Finanzierung der gesetzlichen Rentenversicherung einzusteigen, betritt sie juristisch weitgehend unerforschtes Gebiet. Das gilt insbesondere für die geplante Verwaltung der Stiftung durch den KENFO. Der Beitrag beschreibt den verfassungs-, vergabe-, beihilfe- und steuerrechtlichen Rahmen, in den das Vorhaben eingebettet ist, und unternimmt eine erste Würdigung des Entwurfs in diesem Kontext.
Ausgewählte Aspekte der Krankenhausreform
Authors: Felix Dagmar
Published: September 2024

Die geplante Krankenhausreform gehört zweifellos zu den größten Reformprojekten der letzten Jahre - und angesichts von Preissteigerungen und zunehmender Personalknappheit besteht insoweit offensichtlich auch dringender Handlungsbedarf. Was sich politisch durchsetzen lässt, ist das eine - das andere ist die konkrete juristische Umsetzung der von der Regierungskommission gemachten Vorschläge. Der vorliegende Beitrag befasst sich auf der Grundlage des Entwurfs des KHVVG in der Kabinettsfassung mit einigen ausgewählten Problemfeldern.
Bestimmung einer risikofreien Rendite bei der funktionsschwachen Konzernfinanzierung oder: die Quadratur des Kreises — Eine kritische Analyse und ökonomische Möglichkeiten zur Einschätzung
Authors: Eymann Stefan , Grams Alexander
Published: September 2024

Der Beitrag befasst sich mit der risikofreien Rendite, um eine funktionsschwache Konzernfinanzierungsgesellschaft fremdvergleichskonform zu vergüten. Die OECD-Verrechnungspreisleitlinien 2022 sehen für eine funktionsschwache Konzernfinanzierungsgesellschaft eine Vergütung anhand einer risikofreien Rendite vor. Die OECD erkennt dabei, dass eine Rendite ohne Risiko nicht existiert. Es sind Referenzwerte aufzuzeigen, deren Risiken mit den jeweiligen Leitwährungen Euro und US-Dollar werden hier aufgezeigt.
Der Grundsatz der Einheitlichkeit der Leistung im Fokus von § 12 Abs. 2 Nr. 11 UStG — Zugleich eine Anmerkung zu den Vorlagebeschlüssen des BFH, XI R 11/23, XI R 13/23 und XI R 14/23 v. 10.1.2024
Authors: Nieskens Hans
Published: September 2024

Mit drei weiteren Vorlagebeschlüssen an den EuGH will der BFH nochmals Antworten zum nationalen Aufteilungsgebot bei einer einheitlichen Leistung, diesmal für den Bereich der Steuersatzermäßigungsvorschrift des § 12 Abs. 2 Nr. 11 Satz 2 UStG.
Electromagnetic Subsurface Remote Sensing
Authors: Chen S.Y. , Chew W.C. , Santos V.R.N. , Sainath K. , Teixeira F.L.
Published: August 2016

Fundamental principles and several applications of electromagnetic (EM) subsurface remote sensing methods are outlined and illustrated. Physical insight is emphasized rather than mathematical analysis. The various methods are classified according to the practical embodiment and their range of applications. These include borehole EM methods, ground‐penetrating radar, magnetotelluric methods, airborne methods, inductive EM methods, time‐domain EM methods, and marine EM methods.
Magnetostrictive Devices
Authors: Dapino Marcelo J. , Deng Zhangxiang , Calkins Frederick T. , Flatau Alison B.
Published: August 2016

Magnetostrictive materials exhibit coupling between magnetic and mechanical energies. This bidirectional energy exchange can be employed for actuation, sensing, and energy harvesting. All ferromagnetic materials exhibit the magnetostrictive effect, but only certain iron–rare earth alloys, iron–gallium alloys, amorphous metals, and iron‐ aluminum alloys exhibit sufficiently high magnetostriction for commercial use. Because the magnetostrictive effect is an intrinsic material property that is robust against external factors such as stress and cyclic fatigue, magnetostrictive devices are suitable for harsh environments.

This article provides an overview ofmagnetostrictivematerials and devices, particularly focused on Metglas, Terfenol‐D, and Galfenol. Various transducer topologies are presented and discussed, along with quantification of performance metrics and experimental aspects related to understanding and harnessing the intrinsic nonlinearities of magnetostrictive materials. Selected modeling approaches considering both constitutive material behavior and system response are presented.
Photorefractive Effect: Principles, Materials, and Near‐Infrared Holography
Authors: Marinova Vera , Huei Lin Shiuan , Chung Liu Ren , Hsu Ken Yuh
Published: August 2016

The article consists of two main parts: the first one contains a short summary of the photorefractive effect, discussing the phenomena and the main aspects related to practical applications, followed by a synopsis of the recent progress of photorefractive materials. The second part is devoted to one of the fastest photorefractive materials, sillenite inorganic crystals, focusing in particular on the enhanced photorefractive properties in the near‐infrared spectral range. Examples of real‐time data processing with significant recording speed, as well as realized quasi‐nondestructive holographic recording are also presented. Finally, photonic devices based on the photorefractive nonlinearity, such as optically addressed spatial light modulators and all optically controlled light valves, are discussed.
Swarm Robotics
Authors: Garattoni Lorenzo , Birattari Mauro
Published: August 2016

Swarm robotics is an approach to coordinating a highly redundant group of robots. A robot swarm is an autonomous entity that acts in a self‐organized way: the complexity of its collective behaviors is the result of the local interactions between the individual robots. A robot swarm neither has a leader nor any other centralized entity that is responsible for its coordination. Self‐organization, high redundancy, and the lack of single points of failure promote fault tolerance, scalability, and flexibility. These are desired properties for systems deemed to successfully function in the real world. However, these properties also pose a challenging engineering problem: the behavior of the individual robot cannot be conceived individually: it must be conceived by considering the collective behavior that it produces when executed by a large number of robots. Designing the robot–robot and the robot–environment interactions that would result in the desired collective behavior is a difficult endeavor. Research toward the definition of an engineering methodology for designing, analyzing, and maintaining robot swarms is currently ongoing. In this article, we present swarm robotics from an engineering perspective: we describe works that contribute to the advancement of swarm robotics as an engineering field and to its forthcoming uptake in real‐world applications.
Supervisory Control and Data Acquisition (SCADA): An Introduction
Authors: Tari Zahir , Khalil Ibrahim , Almalawi Abdulmohsen , Fahad Adil , Zomaya Albert Y. , Mahmood Abdun , Queiroz Carlos
Published: August 2016

This article provides a good understanding of the basic elements, concepts, and architecture of SCADA systems, later focusing on one of the challenging issues, namely, SCADA security.
Microcellular Plastics
Authors: Wong Anson , Guo Huimin , Kumar Vipin , Park Chul B. , Suh Nam P.
Published: August 2016

Microcellular plastics are typically thermoplastic polymers with a large number (∼billions per cm3) of tiny bubbles (of the order of 10 μm in diameter). Their densities can range from 3% to 95% of the solid polymer depending on the volume taken by the bubbles (which are denoted as cells in this paper). In general, microcellular plastics exhibit superior impact strength, toughness, fatigue life, thermal stability, dielectric strength, thermal and acoustical insulation performance, as well as optical properties, relatively to the solid counterparts. Other advantages of microcellular plastics include higher productivity due to its faster processing times and sink‐mark free injection‐molded parts with no residual stress and high dimensional stability. Owing to these unique properties, there are a large number of applications of microcellular plastics, particularly in automotive industries. This article summarizes the science and technology of microcellular plastics. To be specific, their history, science (ie, generation of polymer–gas solution, cell nucleation, growth, deterioration and stabilization), solid‐state processing technologies, continuous processing technologies (ie, extrusion and injection molding), design guidelines of each processing technologies, as well as the properties and application of microcellular plastics, are discussed in detail.
Latex Technology for Conductive Polymer Nanocomposites
Authors: Grossiord Nadia , Hermant Marie Claire
Published: August 2016

Latex technology is a unique and scalable process whereby polymeric nano‐ and microcomposites can be prepared. The use of water as a processing media and minimal energy requirements make the process environmentally friendly. Furthermore, the process is applicable to various fillers and polymers. In this article, special attention is paid to various analytical methods with which the process can be monitored and assessed, as well as to strategies to optimize the final composites properties. Focus is placed on conductive nanocomposites prepared using carbon nanotubes and the latex technology process. A brief introduction to the percolation theory of rod‐like fillers is given; the influence that the filler and matrix properties have on this theory and the simulated conductive behavior are also addressed. Methods to manipulate the final composite properties through the clever use of chemical and physical adjustments are described. Finally, applications of materials prepared using latex technology are also discussed.
The scorpion toxin Bot IX is a potent member of the α‐like family and has a unique N‐terminal sequence extension
Authors: Martin‐Eauclaire Marie‐France , Salvatierra Juan , Bosmans Frank , Bougis Pierre E.
Published: August 2016

We report the detailed chemical, immunological and pharmacological characterization of the α‐toxin Bot IX from the Moroccan scorpion Buthus occitanus tunetanus venom. Bot IX, which consists of 70 amino acids, is a highly atypical toxin. It carries a unique N‐terminal sequence extension and is highly lethal in mice. Voltage clamp recordings on oocytes expressing rat Nav1.2 or insect BgNav1 reveal that, similar to other α‐like toxins, Bot IX inhibits fast inactivation of both variants. Moreover, Bot IX belongs to the same structural/immunological group as the α‐like toxin Bot I. Remarkably, radioiodinated Bot IX competes efficiently with the classical α‐toxin AaH II from Androctonus australis, and displays one of the highest affinities for Nav channels.
Comment on “Climate and agricultural land use change impacts on streamflow in the upper midwestern United States,” by Satish C. Gupta et al.
Authors: Belmont Patrick , Stevens John R. , Czuba Jonathan A. , Kumarasamy Karthik , Kelly Sara A.
Published: August 2016

The paper “Climate and agricultural land use change impacts on streamflow in the upper midwestern United States” by Satish C. Gupta, Andrew C. Kessler, Melinda K. Brown, and Francis Zvomuya (hereafter referred to as Gupta et al.) purports to evaluate “the relative importance of changes in precipitation and LULC (land use, land cover) on streamflow in 29 Hydrologic Unit Code 008 watersheds in the Upper Midwestern United States.” However, as we report here, the approach used by Gupta et al. is wholly inadequate for making such an evaluation. Gupta et al. use strong language to criticize other studies and imply a level of certainty that goes well beyond, and in some cases is entirely unsupported by, the results they have presented. We take this opportunity to point out several critical flaws in their study.
Projected changes of Antarctic krill habitat by the end of the 21st century
Authors: Piñones Andrea , Fedorov Alexey V.
Published: August 2016

Climate change is rapidly shaping the living environment of the most abundant keystone species of the Antarctic marine food web, Antarctic krill. Projected future changes for the krill habitat include a sustained increase in ocean temperature and changes in sea ice and chlorophyll a. Here we investigate how these factors affect the early life history of krill and identify the regions around Antarctica where the impact will be greatest. Our tool is a temperature‐dependent krill growth model forced by data from comprehensive greenhouse warming simulations. We find that by the year 2100 localized regions along the western Weddell Sea, isolated areas of the Indian Antarctic , and the Amundsen/Bellingshausen Sea will support successful spawning habitats for krill. The failure of potentially successful spawning will have a strong impact on the already declining adult populations with consequences for the Antarctic marine food web, having both ecological and commercial ramifications.
Eddies reduce denitrification and compress habitats in the Arabian Sea
Authors: Lachkar Zouhair , Smith Shafer , Lévy Marina , Pauluis Olivier
Published: August 2016

The combination of high biological production and weak oceanic ventilation in regions, such as the northern Indian Ocean and the eastern Pacific and Atlantic, cause large‐scale oxygen minimum zones (OMZs) that profoundly affect marine habitats and alter key biogeochemical cycles. Here we investigate the effects of eddies on the Arabian Sea OMZ—the world's thickest—using a suite of regional model simulations with increasing horizontal resolution. We find that isopycnal eddy transport of oxygen to the OMZ region limits the extent of suboxia so reducing denitrification, increasing the supply of nitrate to the surface, and thereby enhancing biological production. That same enhanced production generates more organic matter in the water column, amplifying oxygen consumption below the euphotic zone, thus increasing the extent of hypoxia. Eddy‐driven ventilation likely plays a similar role in other low‐oxygen regions and thus may be crucial in shaping marine habitats and modulating the large‐scale marine nitrogen cycle.
Rapid flattening of butterfly pitch angle distributions of radiation belt electrons by whistler‐mode chorus
Authors: Yang Chang , Su Zhenpeng , Xiao Fuliang , Zheng Huinan , Wang Yuming , Wang Shui , Spence H. E. , Reeves G. D. , Baker D. N. , Blake J. B. , Funsten H. O.
Published: August 2016

Van Allen radiation belt electrons exhibit complex dynamics during geomagnetically active periods. Investigation of electron pitch angle distributions (PADs) can provide important information on the dominant physical mechanisms controlling radiation belt behaviors. Here we report a storm time radiation belt event where energetic electron PADs changed from butterfly distributions to normal or flattop distributions within several hours. Van Allen Probes observations showed that the flattening of butterfly PADs was closely related to the occurrence of whistler‐mode chorus waves. Two‐dimensional quasi‐linear STEERB simulations demonstrate that the observed chorus can resonantly accelerate the near‐equatorially trapped electrons and rapidly flatten the corresponding electron butterfly PADs. These results provide a new insight on how chorus waves affect the dynamic evolution of radiation belt electrons.
Analysis of MESSENGER high‐resolution images of Mercury's hollows and implications for hollow formation
Authors: Blewett David T. , Stadermann Amanda C. , Susorney Hannah C. , Ernst Carolyn M. , Xiao Zhiyong , Chabot Nancy L. , Denevi Brett W. , Murchie Scott L. , McCubbin Francis M. , Kinczyk Mallory J. , Gillis‐Davis Jeffrey J. , Solomon Sean C.
Published: August 2016

High‐resolution images from MESSENGER provide morphological information on the nature and origin of Mercury's hollows, small depressions that likely formed when a volatile constituent was lost from the surface. Because graphite may be a component of the low‐reflectance material that hosts hollows, we suggest that loss of carbon by ion sputtering or conversion to methane by proton irradiation could contribute to hollows formation. Measurements of widespread hollows in 565 images with pixel scales <20 m indicate that the average depth of hollows is 24 ± 16 m. We propose that hollows cease to increase in depth when a volatile‐depleted lag deposit becomes sufficiently thick to protect the underlying surface. The difficulty of developing a lag on steep topography may account for the common occurrence of hollows on crater central peaks and walls. Disruption of the lag, e.g., by secondary cratering, could restart growth of hollows in a location that had been dormant. Images at extremely high resolution (~3 m/pixel) show that the edges of hollows are straight, as expected if the margins formed by scarp retreat. These highest‐resolution images reveal no superposed impact craters, implying that hollows are very young. The width of hollows within rayed crater Balanchine suggests that the maximum time for lateral growth by 1 cm is ~10,000 yr. A process other than entrainment of dust by gases evolved in a steady‐state sublimation‐like process is likely required to explain the high‐reflectance haloes that surround many hollows.
Capillary pressure‐saturation relations in quartz and carbonate sands: Limitations for correlating capillary and wettability influences on air, oil, and supercritical CO2 trapping
Authors: Wang Shibo , Tokunaga Tetsu K. , Wan Jiamin , Dong Wenming , Kim Yongman
Published: August 2016

Capillary pressure (Pc)‐saturation (Sw) relations are essential for predicting equilibrium and flow of immiscible fluid pairs in soils and deeper geologic formations. In systems that are difficult to measure, behavior is often estimated based on capillary scaling of easily measured Pc–Sw relations (e.g., air‐water, and oil‐water), yet the reliability of such approximations needs to be examined. In this study, 17 sets of brine drainage and imbibition curves were measured with air‐brine, decane‐brine, and supercritical (sc) CO2‐brine in homogeneous quartz and carbonate sands, using porous plate systems under ambient (0.1 MPa, 23°C) and reservoir (12.0 MPa, 45°C) conditions. Comparisons between these measurements showed significant differences in residual nonwetting phase saturation, Snw,r. Through applying capillary scaling, changes in interfacial properties were indicated, particularly wettability. With respect to the residual trapping of the nonwetting phases, Snwr, CO2 > Snwr, decane > Snwr, air. Decane‐brine and scCO2‐brine Pc–Sw curves deviated significantly from predictions assuming hydrophilic interactions. Moreover, neither the scaled capillary behavior nor Snw,r for scCO2‐brine were well represented by decane‐brine, apparently because of differences in wettability and viscosities, indicating limitations for using decane (and other organic liquids) as a surrogate fluid in studies intended to apply to geological carbon sequestration. Thus, challenges remain in applying scaling for predicting capillary trapping and multiphase displacement processes across such diverse fields as vadose zone hydrology, enhanced oil recovery, and geologic carbon sequestration.
An analytical solution of Richards' equation providing the physical basis of SCS curve number method and its proportionality relationship
Authors: Hooshyar Milad , Wang Dingbao
Published: August 2016

The empirical proportionality relationship, which indicates that the ratio of cumulative surface runoff and infiltration to their corresponding potentials are equal, is the basis of the extensively used Soil Conservation Service Curve Number (SCS‐CN) method. The objective of this paper is to provide the physical basis of the SCS‐CN method and its proportionality hypothesis from the infiltration excess runoff generation perspective. To achieve this purpose, an analytical solution of Richards' equation is derived for ponded infiltration in shallow water table environment under the following boundary conditions: (1) the soil is saturated at the land surface; and (2) there is a no‐flux boundary which moves downward. The solution is established based on the assumptions of negligible gravitational effect, constant soil water diffusivity, and hydrostatic soil moisture profile between the no‐flux boundary and water table. Based on the derived analytical solution, the proportionality hypothesis is a reasonable approximation for rainfall partitioning at the early stage of ponded infiltration in areas with a shallow water table for coarse textured soils.
Reply to comment by Belmont et al. on “Climate and agricultural land use change impacts on streamflow in the upper midwestern United States”
Authors: Gupta Satish C. , Kessler Andrew C. , Brown Melinda K. , Schuh William M.
Published: August 2016

The reply addresses concerns raised by Belmont et al. (2016) on Gupta et al. (2015) through additional analysis of streamflow versus precipitation relationships for the Whetstone and the Redwood Rivers and with data on available soil moisture in prechange and postchange periods in the Cottonwood River watershed.
Water flow and multicomponent solute transport in drip‐irrigated lysimeters
Authors: Raij Iael , Šimůnek Jiří , Ben‐Gal Alon , Lazarovitch Naftali
Published: August 2016

Controlled experiments and modeling are crucial components in the evaluation of the fate of water and solutes in environmental and agricultural research. Lysimeters are commonly used to determine water and solute balances and assist in making sustainable decisions with respect to soil reclamation, fertilization, or irrigation with low‐quality water. While models are cost‐effective tools for estimating and preventing environmental damage by agricultural activities, their value is highly dependent on the accuracy of their parameterization, often determined by calibration. The main objective of this study was to use measured major ion concentrations collected from drip‐irrigated lysimeters to calibrate the variably saturated water flow model HYDRUS (2D/3D) coupled with the reactive transport model UNSATCHEM. Irrigation alternated between desalinated and brackish waters. Lysimeter drainage and soil solution samples were collected for chemical analysis and used to calibrate the model. A second objective was to demonstrate the potential use of the calibrated model to evaluate lower boundary design options of lysimeters with respect to leaching fractions determined using drainage water fluxes, chloride concentrations, and overall salinity of drainage water, and exchangeable sodium percentage (ESP) in the profile. The model showed that, in the long term, leaching fractions calculated with electrical conductivity values would be affected by the lower boundary condition pressure head, while those calculated with chloride concentrations and water fluxes would not be affected. In addition, clear dissimilarities in ESP profiles were found between lysimeters with different lower boundary conditions, suggesting a potential influence on hydraulic conductivities and flow patterns.
Isoscapes of δ18O and δ2H reveal climatic forcings on Alaska and Yukon precipitation
Authors: Lachniet Matthew S. , Lawson Daniel E. , Stephen Haroon , Sloat Alison R. , Patterson William P.
Published: August 2016

Spatially extensive Arctic stable isotope data are sparse, inhibiting the climatic understanding required to interpret paleoclimate proxy records. To fill this need, we constrained the climatic and physiographic controls on δ18O and δD values of stream waters across Alaska and the Yukon to derive interpolated isoscape maps. δ18O is strongly correlated to winter temperature parameters and similarity of the surface water line (δ2H = 8.0 × δ18O + 6.4) to the Global Meteoric Water Line suggests stream waters are a proxy for meteoric precipitation. We observe extreme orographic δ18O decreases and a trans‐Alaskan continental gradient of −8.3‰ 1000 km−1. Continental gradients are high in coastal zones and low in the interior. Localized δ18O increases indicate inland air mass penetration via topographic lows. Using observed δ18O/temperature gradients, we show that δ18O decreases in a ∼24 ka permafrost ice wedge relative to the late Holocene indicate mean annual and coldest quarter temperature reductions of 8.9 ± 1.7°C and 17.2 ± 3.2°C, respectively.
Plasmodesmata
Authors: Faulkner Christine , Oparka Karl J
Published: August 2016

Plasmodesmata are plasma membrane‐lined pores that span the adjoining walls of plant cells. They permit the intercellular passage of molecules and signals and play a central role in plant physiology and development. Evidence suggests that small molecules can pass from cell to cell by passive diffusion and that this is controlled by regulation of the pore itself. This contributes to processes such as the transport of sugars between cells and tissues. Many endogenous plant proteins and ribonucleic acid (RNA)‐based signals also utilise plasmodesmata for cell‐to‐cell and long‐distance movement. Recent data suggests that plasmodesmata are tightly controlled during development and in response to environmental changes. There is increasing evidence that this regulation is controlled by proteins that have specific plasmodesmata‐associated functions in stimulus perception and signalling. In addition, many viruses exploit plasmodesmata for cell‐to‐cell spread during infection and their encoded viral movement proteins manipulate the pores to facilitate this process.

Key Concepts

Plant cells are connected to each other by cytoplasmic bridges called plasmodesmata. The continuous interconnected cytoplasm in plants is referred to as the symplasm.

A tube of endoplasmic reticulum passes through plasmodesmata and connects the endoplasmic reticulum of neighbouring cells, thus providing endomembrane continuity between cells.

Primary plasmodesmata are formed at cytokinesis when strands of endoplasmic reticulum are trapped between fusing vesicles in the developing cell wall.

Secondary plasmodesmata are formed across existing cell walls, including those at graft unions, and usually arise immediately adjacent to existing plasmodesmata.

Molecules smaller than the size exclusion limit (SEL) of plasmodesmata are able to move freely through the cytoplasmic channel of plasmodesmata by simple diffusion.

The SEL of plasmodesmata may increase or decrease to allow changes in plasmodesmatal conductance. This may occur under different conditions, for example, in response to intracellular factors such as cytoplasmic calcium levels or pathogen perception.

Some endogenous proteins and some movement proteins encoded by plant viruses are able to increase the SEL of plasmodesmata to facilitate their own passage into neighbouring cells. This enables these proteins to function in cells in which they are not normally expressed.

Groups of cells may be connected by plasmodesmata that share an SEL different to that of neighbouring cells. These regions of cells are called symplasmic domains.

Some proteins and RNA molecules pass into the plant's translocation stream and move over long distances. These macromolecules traffic through the plasmodesmata that join sieve elements (SE) and companion cells within the phloem. These macromolecules may have a site of action distant to their site of expression and synthesis.
History of Bacteriology
Authors: Kreuder‐Sonnen Katharina
Published: August 2016

Bacteriology was established in the 1880s as the science of disease germs. However, experimental explorations in the world of microorganisms had started already in the seventeenth century, and botanists and zoologists in the eighteenth century had tried to structure and classify the world of the invisible living organisms. With the German physician Robert Koch the science of microorganisms moved into the realm of medicine. Koch identified several bacteria as the causes of infectious diseases and he contributed greatly to the stabilisation of distinct bacterial species. Medical bacteriology promoted laboratory medicine and Louis Pasteur in Paris developed techniques to attenuate microorganisms in order to produce vaccines. Antibiotics became widely available only after the Second World War. Bacteriology has also developed in relation to agriculture, water (pollution) and biotechnology. Non‐medical approaches to the micro‐world contributed to a broader understanding of microorganisms not only as pathogens but as essential entities in ecological life cycles. At the turn of the twenty‐first century, reductionist views of host–parasite relation gave way to more complex, process‐orientated and environmentalist approaches.

Key Concepts

First experimental encounters with microorganisms took place using microscopic techniques in the seventeenth century.

Classification of microorganisms was discussed by zoologists and botanists since the mid‐eighteenth century.

A causal linkage between microorganisms and disease was established only in the last third of the nineteenth century.

Medical bacteriology developed around the laboratories of Robert Koch and Louis Pasteur and had tremendous effects on public health as well as on conceptions of the body and disease.

Robert Koch's bacteriological thought style implied a reductionist approach to infectious disease.

Broadly applicable antibacterial therapeutic remedies (antibiotics) became widely available only in the second half of the twentieth century.

Bacteriology has also developed in relation to agriculture, marine biology, water pollution, bacterial genetics and biotechnologies.

Environmentalist and evolutionary approaches to microorganisms and host–parasite relation prevailed at the turn to the twenty‐first century.
Meta‐Analysis and Systematic Reviews in Ecology
Authors: Hillebrand Helmut , Gurevitch Jessica
Published: August 2016

Research synthesis provides the methodological and statistical tools for the scientific integration of results of ecological research, and consists of methods and standards for systematic review and meta‐analysis. Systematic reviews use scientific approaches for searching and selecting publications, and meta‐analyses provide the statistical tools to quantitatively summarise study results. These tools can be used to synthesise the outcomes from many different kinds of ecological studies, including both experimental and observational studies taken from published literature, and the outcomes of studies conducted across different systems by coordinated research groups. Based on the rationale for such synthesis efforts, the article presents the types of effect sizes used as well as statistical analyses to test hypotheses.

Key Concepts

Systematic reviews and meta‐analyses are essential for generalising the outcomes of ecological, conservation and evolutionary studies.

Meta‐analysis is the basis for evidence‐based decisions and conclusions in conservation and fundamental ecology

Systematic review is a set of scientific methods for searching, inclusion and reporting results in research syntheses.

Meta‐analysis provides the statistical methods for the quantitative synthesis of the results of different studies.

Meta‐analytic methods offer ways to model and account for heterogeneity in the outcomes of different studies

Meta‐analyses offer the potential to resolve apparent discrepancies in study results and to reconcile longstanding scientific controversies

Meta‐analysis has altered the way ecologists and evolutionary biologists develop general insights beyond the specific contexts of individual studies.
Predictive Genetic Testing: The
H
untington Disease Model
Authors: Tibben Aad , Bijlsma Emilia
Published: August 2016

Predictive or presymptomatic genetic testing enables individuals at risk for a hereditary late‐onset disease to learn about their genetic status before symptoms have appeared. The predictive testing protocol for Huntington disease (HD) safeguards the interests of test candidates and has served as a model for other diseases. Most people seen for genetic counselling regarding HD are the asymptomatic children of an affected parent. Predictive testing provides the opportunity to get relief from the anguish of being at risk, to have prenatal tests or preimplantation genetic testing in order to have children free of the disorder, and to make informed plans for the future regarding marriage, education, professional career and finances. The common experience has been that tested individuals found relief from their prior psychological distress and that they benefited psychologically. Having children proved to be an additional stress factor for partners.

Key Concepts

Predictive testing provides the opportunity to get relief from uncertainty and prepare better for the future.

Preimplantation genetic testing enables couples to have a pregnancy without the burden of termination after an unfavourable prenatal test result.

At 55 years of age and being not symptomatic, there is still a 25% empirical chance of being a carrier of the Huntington's gene.

The Huntington disease CAG repeat length accounts for roughly 50–77% of the variation in the age of onset.

Predictive testing requires informed consent by the individual at risk and the provision of psychological support.

Predictive testing for adult‐onset disorders without treatment options should not be offered to children and adolescents.

Counselling test candidates at 25% risk to get Huntington disease requires a family system approach.

The predictive test candidate's beliefs about causation and emotional, social and cultural issues may affect the perception of the information that is given in genetic counselling.
Genetic Counselling Profession inEurope
Authors: Paneque Milena , Moldovan Ramona , Cordier Christophe , Serra‐Juhé Clara , Feroce Irene , Bjørnevoll Inga , Lambert Debby , Skirton Heather
Published: August 2016

Genetic healthcare has developed as a specialty in Europe over the past five decades and initially services were provided by medical specialists. However, due to changes in awareness of the psychosocial impact of genetic conditions, the amount of new options available to families and the consequent workload increase, clinical genetic services are now frequently provided by multidisciplinary teams. In many European countries, nonmedical genetic counsellors are working as part of the clinical team, providing both information and support for individuals and families at risk of or are affected by genetic conditions. Many genetic counsellors have a background in nursing or other health profession or have completed a Master level degree in genetic counselling. The European Board of Medical Genetics has supported genetic counselling as a profession in Europe through the development of standards of competence, promoting educational pathways for practitioners and managing a registration system for genetic nurses and genetic counsellors.

Key Concepts

Awareness of human heredity was advanced in the nineteenth century through the work of Mendel and Galton.

Specialist clinical genetic services were established in Europe in the mid‐twentieth century.

Genetic counselling is a task that may be undertaken by appropriately trained practitioners from a range of health professions.

Professional genetic counsellors are (nonmedical) practitioners with a background in one of the health professions or have undertaken a Master degree in genetic counselling.

Genetic counsellors provide information, discuss options, support adjustment and facilitate the client to make decisions.

Genetic counsellors are specially trained to offer the client psychological support.

There are disparities in the ways in which genetic counsellors work in different European countries.

In Europe, where different health and educational systems exist in each country, a uniform standard of competence is needed to ensure patient safety.

The European Board of Medical Genetics has developed standards of competence and is promoting educational pathways for practitioners.

The European Board of Medical Genetics assesses practitioners and registers those who are assessed as competent.
Microsatellites
Authors: Hoffjan Sabine , Epplen Jörg T
Published: August 2016

Microsatellites are short, in‐tandem arranged repetitive deoxyribonucleic acid (DNA) elements which are widespread in eukaryotic and prokaryotic genomes. The basic unit lengths of microsatellites (or simple DNA sequence repeats) comprise up to six (or eight) nucleotides, and these motifs are perfectly reiterated from 5 to more than 100 times. Longer and more imperfectly reiterated periodicities border on the definitions of the so‐called minisatellites. Microsatellites have been utilised as markers for population genetic studies, forensic and relatedness testing, investigations on genetic diversity and the identification of genetic traits. However, microsatellite expansions are also involved in human diseases. Lynch syndrome, a hereditary tumour predisposition disease, is characterised by microsatellite instability due to defective mismatch repair, promoting tumourigenesis. Furthermore, microsatellite expansion diseases are rare, but interesting model diseases characterised by diverse pathogenetic pathways. Hence microsatellites exhibit a broad spectrum of biological relevance ranging from neutral or selfish to pathogenic elements.

Key Concepts

Microsatellites exhibit perfect tandem repetition of short nucleotide motifs.

Microsatellites represent most variable components throughout most genomes.

The biological significance of microsatellites ranges from selfishness and molecular marker for a small genome region to disease‐causing mutations when expanded, respectively.
Genetic Counselling forMuslim Families ofPakistani andBangladeshi Origin inBritain
Authors: Shaw Alison
Published: August 2016

Establishing a patient's ethnicity, family history of genetic disease and family history of parental consanguinity is relevant for ascertaining risk in genetic counselling. In the United Kingdom, rates of congenital anomaly are highest among Pakistani children. Fewer congenital anomalies have been reported among British Bangladeshi children. Parental consanguinity is a risk factor for congenital anomaly. In ascertaining consanguinity, genetic counsellors need to avoid stigmatising Pakistani and Bangladeshi patients on the basis of any presumed or actual consanguinity. The focus should be on establishing risk, explaining the pattern of inheritance of an identified genetic condition and offering strategies for risk management. In the case of autosomal recessive conditions, it is important to clarify the difference between being a carrier of a recessive condition and being affected by that condition. Patients' prior understandings of illness causality and modes inheritance, their religious beliefs, language use and aspects of their family structure can also influence their access and responses to genetic counselling. These factors are not static markers of Bangladeshi or Pakistani ethnicity but vary within and between families, across generations and from one case to another. Genetic counsellors need to be aware of the range of ideas that patients may bring to a genetics consultation without presuming that any particular set of ideas will apply in any given case.

Key Concepts

Parental consanguinity elevates the risk of autosomal recessive conditions.

When ascertaining consanguinity, clinicians should avoid giving an undue negative emphasis to cousin marriages.

Some patients' understandings of genetic inheritance may depart from Mendelian principles.

Eliciting patients' understandings of the causes of genetic illness and mechanisms of inheritance is important for effective genetic counselling.

Patients may not know that autosomal recessive conditions are caused by inheriting a mutation in the same gene from both parents – the mother and the father.

Patients may not appreciate the importance of establishing carrier status for managing risk for known autosomal recessive conditions in the family.

Gender, status and position within their family can influence a patient's access to and interpretation of genetic risk information.

Some Islamic rulings permit termination of pregnancy for an abnormal fetus in the first 120 days of conception.

The relevance of Islamic opinions in reproductive decisions varies between individuals, depends on circumstances and can change over time.
Behaviour Genetics: A Critical Perspective on the Role of Genes in Behaviour
Authors: Järvilehto Timo , Lickliter Robert
Published: August 2016

Much effort in behavioural genetics has been motivated by the hope that one day aspects of human behaviour will be explicable in genetic terms. This hope is based on the assumption that the contribution of genetic and environmental factors to behaviour can somehow be partitioned. However, recent advances in genomics, epigenetics, cellular and developmental biology and developmental psychology have made it clear that such partitioning is biologically implausible. The functional significance of genes or any other influence on phenotypic development can be understood only in relation to the organism–environment system of which they are a part. Genes and environments are neither alternative nor independent causes for behavioural development.

Key Concepts

Genes, in and of themselves, cannot produce any behavioural outcome.

The function of a gene cannot be separated from the multiple contexts and environments in which it functions.

Contrary to the assumptions of behavioural genetics, genes and environment do not make independent contributions to behavioural development.

Behaviour without genes is as impossible as is behaviour without an environment.

It is not possible to meaningfully estimate the risk of getting a given disease only on the basis of genetic factors.
Myxobacteria
Authors: Hartzell Trish
Published: August 2016

Myxobacteria are Gram‐negative, rod‐shaped bacteria that are nearly ubiquitous in the biosphere. They forage on living and dead decaying material including bacteria and eukaryotic microbes. As such, myxobacteria appear to play an important role as scavengers cleaning up biological detritus in the environment. Isolates belonging to different genera can be distinguished by the shape of their vegetative cells, motility, pigments, as well as by the type of fruiting bodies and spores produced during their developmental cycle, which is a unique feature of this group. The ability to manipulate myxobacteria genetically combined with their complex processes including synthesis of secondary metabolites, foraging and predation, TraA‐dependent kin‐recognition, outer membrane exchange, fruiting body development, phase variation and gliding motility – makes them excellent research subjects.

Key Concepts

Social interactions in the myxobacteria are important for swarming, feeding and development.

Kin recognition and sibling killing involve a cell surface receptor, TraA.

Phase variation yields cells with specialised functions.

Predation involves release of hydrolytic enzymes that allow myxobacteria to feed on other microbes.

Myxococcus cells use small molecules (signals) to communicate and coordinate the fruiting body construction.
Biotic Homogenisation
Authors: Olden Julian D , Comte Lise , Giam Xingli
Published: August 2016

Biotic homogenisation is the process by which species invasions and extinctions increase the genetic, taxonomic or functional similarity of two or more locations over a specified time interval. Recent years have witnessed enhanced interest and research effort in the study of biotic homogenisation across taxonomic groups and geographic regions, with the first article published over 20 years ago. Despite sustained interest, past research efforts have been unevenly distributed with regard to taxonomic groups and ecosystems. Biotic homogenisation of vertebrate and plant communities have been studied the most, while invertebrates have received little attention. Concurrent with heightened quantification of biotic homogenisation, is continued clarification on the significant ecological, evolutionary and social consequences of this phenomenon. Biotic homogenisation is now considered one of the most prominent forms of biotic impoverishment worldwide, and it will likely continue to increase in response to anthropogenic forces associated with growing human populations.

Key Concepts

In the wake of continued human‐driven species invasions and extinctions, the process of biotic homogenisation has rapidly emerged as a topic of interest in conservation biology.

Biotic homogenisation is the process by which species invasions and extinctions increase the genetic, taxonomic or functional similarity of two or more locations over a specified time interval.

This is a unique research challenge, because it is a multifaceted process that subsumes many aspects of the modern biodiversity crisis, including species invasions, extirpations and environmental alteration.

Current knowledge of the patterns, mechanisms and implications of biotic homogenisation is highly variable across taxonomic groups, but in general is most complete for freshwater fishes, birds and plants.

Biotic homogenisation is an important dimension of the modern biodiversity crisis having significant ecological, evolutionary and social implications.