299 research outputs found
Traceable Standards for Electrolytic Conductivity Measurements Required for Pharmaceutical Production
Certified reference materials for low electrolytic conductivity can now be produced successfully that meet the basic criteria of a high quality technical standard for industrial purposes. The materials are very stable and easy to handle. The values for these high quality references
have low uncertainties and are traceable to international standards by an unbroken chain of comparison. These certified reference materials can be used to check the compliance with the requirements for pharmaceutical grades of water. Water for injection (WFI) or highly purified water (HPW)
can now be checked reliably against the limiting values set by the European and United States Pharmacopeia using instruments that are calibrated with low level electrolytic standards. The comparability of the results has been demonstrated on occasion of an intercomparison between expert reference
laboratories
Vom Sofa in den Sport-Olymp: Aspekte von Rollenspiel und Adventure in den Sport-Spielreihen NBA2K und Fifa
Hast du schon immer davon geträumt, im NBA-Finale zu stehen? Oder bist du vor dem Fernseher verzweifelt, wenn das Lieblingsteam in der Champions League den entscheidenden Penalty verschossen hat? Dann nimm es selbst in die Hand, denn im neusten Wurf der NBA2K-Spielerreihe kannst du per Scan des eigenen Gesichts mit der zugehörigen Smartphone Applikation direkt ins Geschehen eingreifen. Nun liegt es an dir, dein Lieblingsteam zu Ruhm und Ehre zu führen und zum Schluss im Ruhestand den wohlverdienten Platz neben den Sportlegenden einzunehmen.
Das Aushängeschild der in diesem Beitrag thematisierten Sportspiele ist der 'My Player/Career'-Modus. Als Spieler/in kommt man selbst so nah an das Geschehen wie möglich, indem man einen Avatar kreiert, diesen personalisiert, trainiert und damit eine möglichst erfolgreiche Sportkarriere zu absolvieren versucht. Dabei drängen sich Assoziationen zu Role-Playing Games (RPGs), wie sie sonst v. a. mit Fantasy und Science Fiction in Verbindung gebracht werden, unweigerlich auf.
Aufgrund dieser Irritation möchte ich mich in meinem Artikel ausgewählten Sportspielen widmen und der Frage nachgehen, welche Rollenspielelemente darin aufzufinden sind und wie sie eingesetzt werden. Den Fokus richte ich dabei auf die Basketballspiele NBA2K17 (2016) und NBA2K12 (2011) und die Fussballspiele Fifa12 (2011) und Fifa06 (2005) sowie auf NBA Street V3 (2005), das nicht einer der beiden grossen Spielreihen entstammt und damit als Vergleichsgegenstand dienen soll
A microsensor array for biochemical sensing
A microsensor array to measure chemical properties of biological liquids is presented. A hybrid integration technique is used to mount four sensor chips on a micro flow channel: a pressure, temperature, pH, combined pO2 and pCO2 sensor chip. This results in a microsensor array which is developed to meet the technical requirements for space applications. The integration method allows to integrate other types of sensor chips. This multi-purpose and multi-user approach makes the microsensor array suitable for various biochemical applications
Spatially Controlled Membrane Depositions for Silicon-Based Sensors
The membrane deposition technology on silicon-based transducers constitutes the most delicate part of the miniaturized (bio)chemical sensor fabrication. Membrane adhesion to the transducer, reproducibility of the deposition process and its spatial control are the three most important parameters which determine the sensor performance and lifetime.The fabrication of two sensors is described: 1) a combined pO2, pCO2, pH sensor for which a polyacrylamide gel and a polysiloxane gas-permeable membrane were deposited and patterned at the on-wafer level and 2) a glucose amperometric enzyme electrode where the glucose oxidase was immobilized electrochemically either in a polypyrrole matrix or co-deposited with bovine serum albumin by electrochemically aided adsorption. The optimization of the deposition procedures allowed reproducible devices with reasonable lifetimes to be obtained
Development of a Space Bioreactor using Microtechnology
A miniature bio-reactor for the cultivation of cells aboard Spacelab is presented. Yeast cells are grown in a 3 milliliter reactor chamber. A supply of fresh nutrient medium is provided by a piezo-electric silicon micro-pump. In the reactor, pH, temperature, and redox potential are monitored and the pH is regulated at a constant value. The complete instrument is fitted in a standard experiment container of 63 x 63 x 85 mm. The bioreactor was used on the IML-2 mission in July 1994 and is being refurbished for a reflight in the spring of 1996
Mechanisms of HsSAS-6 assembly promoting centriole formation in human cells
SAS-6 proteins are thought to impart the ninefold symmetry of centrioles, but the mechanisms by which their assembly occurs within cells remain elusive. In this paper, we provide evidence that the N-terminal, coiled-coil, and C-terminal domains of HsSAS-6 are each required for procentriole formation in human cells. Moreover, the coiled coil is necessary and sufficient to mediate HsSAS-6 centrosomal targeting. High-resolution imaging reveals that GFP-tagged HsSAS-6 variants localize in a torus around the base of the parental centriole before S phase, perhaps indicative of an initial loading platform. Moreover, fluorescence recovery after photobleaching analysis demonstrates that HsSAS-6 is immobilized progressively at centrosomes during cell cycle progression. Using fluorescence correlation spectroscopy and three-dimensional stochastic optical reconstruction microscopy, we uncover that HsSAS-6 is present in the cytoplasm primarily as a homodimer and that its oligomerization into a ninefold symmetrical ring occurs at centrioles. Together, our findings lead us to propose a mechanism whereby HsSAS-6 homodimers are targeted to centrosomes where the local environment and high concentration of HsSAS-6 promote oligomerization, thus initiating procentriole formation
Distinct mechanisms eliminate mother and daughter centrioles in meiosis of starfish oocytes
Centriole elimination is an essential process that occurs in female meiosis of metazoa to reset centriole number in the zygote at fertilization. How centrioles are eliminated remains poorly understood. Here we visualize the entire elimination process live in starfish oocytes. Using specific fluorescent markers, we demonstrate that the two older, mother centrioles are selectively removed from the oocyte by extrusion into polar bodies. We show that this requires specific positioning of the second meiotic spindle, achieved by dynein-driven transport, and anchorage of the mother centriole to the plasma membrane via mother-specific appendages. In contrast, the single daughter centriole remaining in the egg is eliminated before the first embryonic cleavage. We demonstrate that these distinct elimination mechanisms are necessary because if mother centrioles are artificially retained, they cannot be inactivated, resulting in multipolar zygotic spindles. Thus, our findings reveal a dual mechanism to eliminate centrioles: mothers are physically removed, whereas daughters are eliminated in the cytoplasm, preparing the egg for fertilization.European Molecular Biology Laboratory (EMBL)- EMBL International PhD Program; Laura and Arthur Colwin Endowed Summer Research Fellowship; Deutsche Forschungsgemeinschaft grant: (MU1423/4-1)
Crystal structures of the CPAP/STIL complex reveal its role in centriole assembly and human microcephaly.
Centrioles organise centrosomes and template cilia and flagella. Several centriole and centrosome proteins have been linked to microcephaly (MCPH), a neuro-developmental disease associated with small brain size. CPAP (MCPH6) and STIL (MCPH7) are required for centriole assembly, but it is unclear how mutations in them lead to microcephaly. We show that the TCP domain of CPAP constitutes a novel proline recognition domain that forms a 1:1 complex with a short, highly conserved target motif in STIL. Crystal structures of this complex reveal an unusual, all-β structure adopted by the TCP domain and explain how a microcephaly mutation in CPAP compromises complex formation. Through point mutations, we demonstrate that complex formation is essential for centriole duplication in vivo. Our studies provide the first structural insight into how the malfunction of centriole proteins results in human disease and also reveal that the CPAP-STIL interaction constitutes a conserved key step in centriole biogenesis. DOI:http://dx.doi.org/10.7554/eLife.01071.001
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