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Hajek, F, Keller, M, Taube, W, von Duvillard, SP, Bell, JW, and Wagner, H. Testing-specific skating performance in ice hockey. J Strength Cond Res35(12S): S70–S75, 2020—Skating performance generally determines overall performance in ice hockey but has not been measured adequately in the past. Consequently, the aim of the study was to develop and validate a specific overall skating performance test for ice hockey (SOSPT) that includes similar movements and intensities as in competition. Ten male elite under-14-year and under-18-year old ice hockey players performed the SOSPT (2 heats only) and a 40-m on-ice sprinting test twice within 8 days. Additionally, 14 under-15, 18 under-17, and 20 under-20 male elite ice hockey players performed only the SOSPT (4 heats). Time was measured from the first subject's movement during a V-start until crossing the line (40-m on-ice sprinting test), first touch of the shoulder on the mat (heat #1 in the SOSPT) or first touch of the puck with the stick (heat #2 in the SOSPT) using a hand stopwatch. We found a high test-retest reliability of the SOSPT and 40-m on-ice sprinting test (interclass correlation coefficient, >0.7; coefficient of variation, <5%) with highly significant differences (p< 0.001) between the under-15, under-17, and under-20 players, a high correlation (r> 0.70) between an expert rating and the SOSPT, and a low correlation between the 40-m on-ice sprinting test and the SOSPT in the under-14 and under-18 players. The results of the study reveal that the SOSPT is a reliable and valid test to determine the specific overall skating performance in ice hockey players and is more suitable compared with straight skating tests of the 40-m on-ice sprinting test.

The effect of methylation of an enhancer on transcription was studied. A 245 bp enhancer-containing a fragment of the LTR of the avian sarcoma virus was methylated in vitro and ligated back into a vector which lacked the upstream enhancer sequence. The transient expression in QT6 cells indicated that methylation of the enhancer-containing sequence severely reduced the extent of transcription.

Methylation of cytosine in the DNA inhibits the transcription by RNA polymerase II in higher eukaryotes, but has no influence on RNA polymerase I transcription. The effect on RNA polymerase III was unknown, so far. Two polymerase III genes: a type 1 5S rRNA gene and a type 2 tRNA gene were methylated in vitro with a purified eukaryotic DNA methyltransferase (EC2.1.1.37) and their transcription was analyzed in Xenopusoocytes. The 5S rRNA gene, an oocyte 5S rRNA gene from X. laeviswhich is subject to developmental inactivation, was not affected by methylation. Conversely, transcription of the tRNA gene was 80% inhibited by methylation with the eukaryotic methyltransferase. HhaI and HpaII methylation left its transcription unaffected.

We study the statistical mechanics of hydrogen dissolved in metals. The underlying model is based on the assumption that the dominant attractive interaction between the protons in the metal is of an elastic nature.In the first part of the paper we review some general properties of the elastic interaction. We then discuss the importance of boundary conditions for the form of the elastic interaction, which turns out to be of the Curie-Weiss type with macroscopic range.In the second part we investigate the a-a' (‘gas-liquid’) phase transition in the hydrogen lattice fluid. The long-range part of the elastic interaction is treated in mean field approximation. In the canonical ensemble as opposed to the grand canonical ensemble one finds no co-existing phases near the critical point. Instead there is a continuous transition which changes into a first-order transition at tricritical points. In the temperature-density region which normally corresponds to the two-phase co-existence region the hydrogen density is inhomogeneous and varies on a macroscopic scale.The peculiar nature of the a-a' phase transition is due to the long-range character of the elastic interaction, which ultimately results from the requirement of coherency of the host crystal. We argue that coherent metal-hydrogen systems offer examples of real systems where the classical theory of phase transitions applies.

In order to quantify the invasiveness of melanoma tumor cellsin vitro, a modification of the amniotic basement membrane (BM) model, described by Liottaet al.(Cancer Letters,11, 141, 1980), was used in combination with radiolabeled tumor cells. B16-F10 metastatic murine melanoma cells and a derived clone (B16-F10L) were prelabeled with 0·1 μCi/ml of [14C]thymidine for 20–24 h in serum-free medium at 37°C. Following incubation, fetal bovine serum was added to a concentration of 5 per cent, and the cells were allowed to grow to confluency for the next 24–28 h. The labeled cells were seeded onto amniotic membranes situated in Membrane Invasion Culture System (MICS) chambers at a density of 2·5×104per well. At various times points, radioactivity of tumor cells that completely traversed the membrane was determined using an under-the-membrane sampling method. The average percent invasion demonstrated by the B16-F10 line was 2·75 per cent, and 3·65 per cent exhibited by the B16-F10L cell line after 48–53 hin vitro.Since it was apparent that some variability in thickness existed among membrane samples, a morphological analysis was performed on five sectors of a three-inch-diameter sample from four different placentae. Differences and similarities in BM thickness within the same sector were noted by this technique and could possibly contribute to some variability observed in tumor cell invasion in this model. Another parameter examined was the proliferation of tumor cells in the upper and lower wells of the MICS chambers. By 48 h, approximately 32·1 per cent of the B16-F10 cell line as well as the clone had replicated in the upper wells associated with the BMs compared with a 32·9 per cent replication in the lower wells, which reaffirmed the viability of the tumor cells under experimental conditions and insured similarly replicating populations of cells. In order to quantify the invasiveness of radiolabeled tumor cells accurately through a biological membranous barrier, the proper concentration of cells must be used, tumor cell heterogeneity should be taken into consideration, the technique of sampling radiolabeled invasive cells should be critically analysed, and thickness of the membranous barrier should all be considered as possible important factors in the quantitative analyses.

Methylation of cytosine in the DNA inhibits the transcription by RNA polymerase II in higher eukaryotes, but has no influence on RNA polymerase I transcription. The effect on RNA polymerase III was unknown, so far. Two polymerase III genes: a type 1 5S rRNA gene and a type 2 tRNA gene were methylated in vitro with a purified eukaryotic DNA methyltransferase (EC2.1.1.37) and their transcription was analyzed in Xenopusoocytes. The 5S rRNA gene, an oocyte 5S rRNA gene from X. laeviswhich is subject to developmental inactivation, was not affected by methylation. Conversely, transcription of the tRNA gene was 80% inhibited by methylation with the eukaryotic methyltransferase. HhaI and HpaII methylation left its transcription unaffected.

Primary cell lines of fibroblasts from 8 tissues were established-three from hypertrophic scars (HS), one keloid (K) and four from the normal uninvolved dermis adjacent to each lesion. The objective was to quantify and compare all eight cell lines on the basis of fibronectin (FN) produced per cell and per total protein (PR). Two hypertrophic scars and their adjacent skin cell lines were evaluated by the ELISA method for FN and a micro Lowry assay for PR. The scar lines showed statistically significant increases in the amount of FN/cell compared to the cell lines from their adjacent normal dermis. The third hypertrophic scar and the keloid with their adjacent skin cell lines were assayed for FN and PR by radioimmunoprecipitation. Subconfluent cells were metabolically labeled with 35S-methionine for 20 hours. Harvested media and cell monolayers were assayed for radioactivity incorporated into FN and PR. The percentage of FN/PR was significantly higher in media for HS and K compared to the adjacent normal skin lines in the three passages tested. These results support our previous immunofluorescence studies and demonstrate that a fibroblast-type cell line from a hypertrophic scar or keloid produces more FN/PR over time than the normal fibroblast-type cell line from adjacent uninvolved dermis.

We consider geometrically disordered systems with a continuous symmetry groupG, where the internal degrees of freedom are attached to the vertices of a graph. We show that equilibrium states remainG-invariant at any temperatureT>0 if a random walk on the graph is recurrent. This generalizes a previous result obtained by Cassi.

We extend the thermodynamic theory of hydrogen in metals to include the effect of internal coherence strains on the electromigration of interstitially dissolved protons. We study, in particular, the long-time behavior of local density relaxation near a critical point of the hydrogen lattice fluid. The contingency of damped oscillatory relaxation is discussed.

The effect of methylation of an enhancer on transcription was studied. A 245 bp enhancer‐containing a fragment of the LTR of the avian sarcoma virus was methylated in vitro and ligated back into a vector which lacked the upstream enhancer sequence. The transient expression in QT6 cells indicated that methylation of the enhancer‐containing sequence severely reduced the extent of transcription.

Two planar Ising models on compressible lattices are considered. The elastic forces act in the horizontal direction only and between nearest-neighbors, but are otherwise arbitrary. The nearest-neighbor exchange interaction is taken as constant for two spins with the same column index and depending on separation for spins on the same row. In the first model (A) the transition remains continuous, and Fisher's theory of renormalized exponents applies; in the second model (B) the additional constraint that spins on a column move as a unit changes the transition to first order.

Zusammenfassung Es wird eine planparallele, röntgenoptisch ideale Kristallplatte imBragg-Fall der Interferenz theoretisch untersucht. Im Unterschied zu der Betrachtungsweise P. P.Ewalds, der eine seitlich unendlich ausgedehnt ins Gitter einfallende Welle voraussetzt, wird hier angenommen, die Welle sei seitlich engbegrenzt. Als Folge der nunmehr geänderten Randbedingungen an der Eintrittsfläche wird die Strahlung zwischen den Plattenbegrenzungen hin und her reflektiert. In einem Teil des Interferenzbereichs unterliegt die Strahlung anomal schwacher Absorption. Nach Umrechnung des auf die Plattennormale bezogenen Absorptionskoeffizienten auf den Strahlweg lä\t sich die Energieverteilung im Kristallinnern und an den Austrittsflächen, unter der dem Experiment angepa\ten Annahme eines schwach divergent ins Gitter einfallenden Röntgenstrahlbündels, berechnen. In übereinstimmung mit dem Experiment ergibt die Rechnung den kontinuierlichen übergang in der Intensität der durchgehenden Strahlung beim Wechsel vomLaue- zumBragg-Fall.

The isothermal elastic constants and the coefficient of anomalous thermal expansion of a magnetic lattice are discussed. The spin system is described by the Ising model with an exchange coupling depending on lattice spacing. A behavior of the elastic constants and the coefficient of thermal expansion is found which is in qualitative agreement with experiments. The isothermal compressibility remains positive nearTcand no thermo-mechanical instability occurs (which would lead to a first-order phase transitions), in contrast to earlier theories.

Long-wavelength excitations in ferro-, antiferromagnets, superfluids and crystals are studied in connection with the nonrelativistic Goldstone theorem. It is shown that, except in the example of superfluids, the statement of “broken symmetry” together with the local conservation laws implies the existence of gapless excitations in the limit of vanishing momenta (magnons, phonons). For this purpose a generalized version of Bogoliubov's 1/k2-theorem is derived. This theorem is valid for all examples considered in this paper and yields long-range order in certain correlation-functions which are specific for condensed systems with broken symmetry. It is stressed that the longwavelength density-excitation spectra in quantum liquids are insensitive to whether gauge symmetry is broken or not. They are controlled by the range of the interactionpotential. Therefore these density-excitations do not necessarily provide an argument pro or contra the nonrelativistic Goldstone theorem.

Two-particle approximations for superfluid Fermion systems are discussed using the functional formalism of ref. A special symmetry of collective excitations is pointed out which links density fluctuations to moving pairs excited from the pair condensate. It is indicated that the description of collective excitations in terms ofT-matrices defined in automatically conserves this symmetry. A generalized ladder approximation is obtained, which is capable of treating collective excitations together with hard-core potentials

Zusammenfassung Organische halogen- und schwefelhaltige Substanzen werden in einem mit Quarzwolle gefüllten Quarzrohr verbrannt und die Verbrennungsprodukte in einem abnehmbaren Spiralrohr absorbiert. Das Halogenion wird anschließend argentometrisch und die Schwefelsäure acidimetrisch titriert.

Zusammenfassung Es wird eine modifizierte Mikrostickstoffapparatur beschrieben, bei der mit Hilfe elektrischer Öfen und einer Automatik verbrannt wird. Als Kohlendioxydquelle wird ein abgeänderterKippscher Apparat vorgeschlagen, der auch nach längeren Ruhepausen sofort einwandfreie Mikroblasen liefert. Die bewegliche Füllung besteht aus zwei leicht zu handhabenden Kupferoxyddrahtnetzrollen, die serienmäßiges Arbeiten erleichtern. Als Einwaage- und Verbrennungsgefäß dient ein beiderseits durch Quarzwollepfropfen verschließbares Röhrchen aus Supremaxglas.

Zusammenfassung Es wird über eine Verbrennungsapparatur für Kohlenstoff-Wasserstoffanalysen berichtet, bei der ein etwas abgeändertes Verbrennungsrohr mit zwei leicht austauschbaren Ansatzstücken verwendet wird. Um möglichst sichere Wasserstoffwerte zu erreichen, werdenstickstofffreie Substanzenohne Bleidioxyd, dagegenstickstoffhaltige mitgealtertem Bleidioxyd im Ansatzstück nach einem bestimmten Schema verbrannt.

The development of the U.S. Environmental Protection Agency (EPA) Method 317.0 is initiated to provide a sufficiently sensitive and fundamental technique for the compliance monitoring of trace levels of bromate in drinking water. After a comparative evaluation of Method 317.0 and elimination of a chlorite interference, this method is tested by a collaborative study in order to determine the precision and bias of the method and evaluate its potential role as a future compliance-monitoring method for inorganic disinfection by-products (DBPs) and trace bromate. This technique provides a practical method for future compliance monitoring for all of the inorganic oxyhalide DBPs including trace concentrations of bromate.