Stratification of centrifuged amoeba nuclei investigated by electron microscopy

Study establishes a relationship between radioresistance and the nucleolar stratification characteristics of various amoeba species. Two species of fresh water amoeba are studied with the electron microscope. The report discusses the nature of nucleolar layers and their possible relationship to the differences in radiosensitivity of the two amoeba species

Narcissism in independent and interdependent cultures

Narcissism can manifest in a grandiose form – admiration-seeking, exhibitionism, and dominance – or a vulnerable form – anxiety, withdrawal, and hypersensitivity. While grandiose narcissism is conceptually in line with an independent self-construal, as prevalent in Western countries, the vulnerable form can be assumed to relate more to an interdependent self-construal, as prevalent in Eastern countries. We studied both forms of narcissism in Germany and Japan (Ns = 258, 280), which differ fundamentally in their independent and interdependent self-construal, yet are similar regarding global developmental standards. We tested whether (1) mean differences in both narcissism forms would conform to the predominant self-construal, (2) self-construal would explain variance in narcissism beyond broad personality traits, and (3) there would be stronger mental health tradeoffs for culturally incongruent forms of narcissism. Our results largely confirm these expectations for vulnerable narcissism, which is (1) more prevalent in Japan than Germany, (2) related to self-construal beyond broad traits, and, (3) more strongly related to mental health problems in Germany than Japan. For grandiose narcissism, data analyses indicated that construct equivalence can only be assumed for the entitlement factor, and internal structure and nomological networks differ substantially between cultural contexts

Graphitization in chromium cast iron

peer reviewedSome trials with graphite Hi-Cr iron rolls have been done mainly in Japan, for the rolling of stainless steel. This material could lead to good compromise between oxidation, wear and thermal behaviour. By using thermal analysis and resistometry, the conditions for secondary graphite formation have been studied. The amount and volume of free graphite may be strongly increased by a suitable heat treatment, allowing a good thermal conductivity as well as high wear and mechanical properties

Online physician reviews: Is there a place for them?

Web-based physician ratings are increasingly popular but imperfect proxies for clinical competence. Yet they provide valuable information to patients and providers when taken in proper context. Providers need to embrace the reviews and use them to enact positive change in order to improve the quality of our patients' experience. Patients need to realize the limitations of online ratings, particularly with smaller sample size and be discerning about the reasons behind the review

The mutual dependence of negative emission technologies and energy systems

While a rapid decommissioning of fossil fuel technologies deserves priority, most climate stabilization scenarios suggest that negative emission technologies (NETs) are required to keep global warming well below 2 °C. Yet, current discussions on NETs are lacking a distinct energy perspective. Prominent NETs, such as bioenergy with carbon capture and storage (BECCS) and direct air carbon capture and storage (DACCS), will integrate differently into the future energy system, requiring a concerted research effort to determine adequate means of deployment. In this perspective, we discuss the importance of energy per carbon metrics, factors of future cost development, and the dynamic response of NETs in intermittent energy systems. The energy implications of NETs deployed at scale are massive, and NETs may conceivably impact future energy systems substantially. DACCS outperform BECCS in terms of primary energy required per ton of carbon sequestered. For different assumptions, DACCS displays a sequestration efficiency of 75–100%, whereas BECCS displays a sequestration efficiency of 50–90% or less if indirect land use change is included. Carbon dioxide removal costs of DACCS are considerably higher than BECCS, but if DACCS modularity and granularity helps to foster technological learning to <100$ per tCO2, DACCS may remove CO2 at gigaton scale. DACCS also requires two magnitudes less land than BECCS. Designing NET systems that match intermittent renewable energies will be key for stringent climate change mitigation. Our results contribute to an emerging understanding of NETs that is notably different to that derived from scenario modelling

The mutual dependence of negative emission technologies and energy systems

While a rapid decommissioning of fossil fuel technologies deserves priority, most climate stabilization scenarios suggest that negative emission technologies (NETs) are required to keep global warming well below 2 °C. Yet, current discussions on NETs are lacking a distinct energy perspective. Prominent NETs, such as bioenergy with carbon capture and storage (BECCS) and direct air carbon capture and storage (DACCS), will integrate differently into the future energy system, requiring a concerted research effort to determine adequate means of deployment. In this perspective, we discuss the importance of energy per carbon metrics, factors of future cost development, and the dynamic response of NETs in intermittent energy systems. The energy implications of NETs deployed at scale are massive, and NETs may conceivably impact future energy systems substantially. DACCS outperform BECCS in terms of primary energy required per ton of carbon sequestered. For different assumptions, DACCS displays a sequestration efficiency of 75–100%, whereas BECCS displays a sequestration efficiency of 50–90% or less if indirect land use change is included. Carbon dioxide removal costs of DACCS are considerably higher than BECCS, but if DACCS modularity and granularity helps to foster technological learning to <100$ per tCO2, DACCS may remove CO2 at gigaton scale. DACCS also requires two magnitudes less land than BECCS. Designing NET systems that match intermittent renewable energies will be key for stringent climate change mitigation. Our results contribute to an emerging understanding of NETs that is notably different to that derived from scenario modelling.TU Berlin, Open-Access-Mittel - 201

A major zebrafish polymorphism resource for genetic mapping

645,088 candidate polymorphisms in zebrafish were identified and positioned on genetic and physical maps as a resource for positional cloning

An SNP-Based Linkage Map for Zebrafish Reveals Sex Determination Loci

A surprising diversity of mechanisms controls sex determination of vertebrate organisms, even among closely related species. Both genetic and temperature-dependent systems of sex determination have been described in teleost fish. In the common zebrafish model organism, heteromorphic sex chromosomes are not observed, and the potential role of a genetic component of sex determination remains largely unknown. Here we report a genome-wide linkage study of sex determination in zebrafish using a novel SNP genetic map. We identified loci on zebrafish chromosomes 5 (LOD score 7.9) and 16 (LOD score 9.3) governing sex determination as a complex trait, rather than as an XY or ZW genetic system. Each of these loci contains a prominent candidate gene with a conserved role in sex determination across additional species that suggest potential mechanisms of sex determination in zebrafish. The chromosome 5 locus harbors dmrt1, a key gene in sex determination from fruit flies to humans; mutation of the human DMRT1 ortholog is a cause of complete sex reversal of XY individuals. The chromosome 16 locus harbors cyp21a2; mutation of the human CYP21A2 ortholog is one of the more common causes of pseudohermaphroditism. Mutation detection at each of these candidate genes within the zebrafish cross identified hypomorphic variants on the female-associated allele of each locus. The two loci together accounted for 16% of variance of the trait. Interacting environmental cues are likely to be an additional important component of sex determination in zebrafish