Fourth Row Research Articles

Film cooling effectiveness distribution on first-stage vane endwall with and without leading-edge fillets

Considered are the effects of leading edge airfoil geometry on endwall film cooling. Three different fillet profiles, with length to height ratios of 2.8, 1.2 and 0.5, are considered, as each is placed at the junction of the airfoil leading edge and endwall. The results of these arrangements are compared with a baseline configuration with no fillet. The film cooling is produced by four rows of compound-angle, laidback fan-shaped holes, where each row of holes is located in the lateral direction. Each fanshaped hole is inclined at an angle of 30° with respect to the endwall surface. The compound angles of the first, second, third, and fourth rows of holes are 0°, 30°, 45°, and 60°, respectively, relative to the axial direction. Each fanshaped hole has a lateral diffusion angle of 10° from the hole-centerline, and a forward expansion angle of 10° relative to the endwall surface. The Reynolds number based on the axial chord and inlet velocity of the free-stream flow is 3.5×105, and the testing is done in a four-blade cascade with low Mach number condition (0.1 at the inlet), while the overall-average blowing ratio of the coolant through the discrete holes is constant at 0.4. Local, surface adiabatic film-cooling effectiveness values are measured using pressure sensitive paint (PSP). For a blowing ratio of 0.4, the baseline geometry (with no fillet) provides the best film cooling performance near leading edge pressure side. As for the leading edge suction side, the best leading edge configuration is the longfillet arrangement, since it is more effective in controlling the suction side leg of the horseshoe vortex compared to the other configurations which are examined.

Confinement-induced orbital breathing, fusion, fission and re-ordering in semifilled shell atoms

Alternate contraction and drastic expansion, i.e., ‘breathing’ of electronic subshells, the effects of the fusion of two subshells into one subshell and its subsequent fission (splitting) into the original subshells, as well as multiple alteration of the order of subshells in confined semifilled shell atoms with a progressively narrowing confinement are theoretically discovered. The confinement is represented by a repulsive penetrable spherical potential of an inner radius r0. The effects are exemplified by calculated data for confined semifilled shell atoms from the second, third and fourth rows of Mendeleev's table—Li, N, P and Cr atoms with semifilled 2s1, 2p3, 3p3 and 3d5 subshells, respectively—for the completeness of the study. The underlying physics behind the discovered effects is explained.

Majorana neutrino mass matrices with three texture zeros and the sterile neutrino

As a consequence of the LSND anomaly and other hints of an eV scale sterile neutrino from particle physics and cosmology, the neutrino sector of the standard model of particle physics has to be extended and the smallest extension is the ($3+1$) model, i.e., three active neutrinos plus one sterile one. In this work we study the neutrino mass matrix ${M}_{\ensuremath{\nu}}$ with three texture zeros in the ($3+1$) model, assuming all the neutrino states are of Majorana type. With the mass hierarchy between the active and sterile neutrinos as well as the smallness of the reactor neutrino mixing and active-sterile mixing, the analytical expressions can be greatly simplified. We systematically examine all the 120 texture zeros, via both analytical and numerical analysis, and find that the 100 textures with zeros in the fourth column and row of ${M}_{\ensuremath{\nu}}$ can hardly be compatible with experiments; whereas, 19 of the other 20 are feasible. We can foresee that the active neutrino masses are required to be around 0.01 eV and the next generation neutrinoless double beta decay experiments are promising to test these textures. Many other phenomenologically meaningful predictions are also obtained. All the $CP$ conserving ($3+1$) textures with three zeros are excluded by experiments.

Anthropology, Linguistics, and the Vicissitudes of Interdisciplinary Collaboration

Anthropology, Linguistics, and the Vicissitudes of Interdisciplinary Collaboration Alan Rumsey (bio) Among all the human sciences, none is more interdisciplinary than anthropology. This has followed almost inevitably from the fact that anthropology has from the start always been concerned with the question of what it is to be human, and therefore with understanding the full range of dimensions along which human societies and cultures resemble or differ from one another.1 As an example of the kind of cross-disciplinary interaction to which this has given rise, in this article I discuss the hybrid field known as linguistic anthropology. My initial discussion is focused on the United States because that is where linguistic anthropology is most fully developed as a subdiscipline of anthropology. In a later section of the article I discuss the situation of linguistic anthropology within Australia, where I have long been based after having been trained in the United States. From the comparison between the two, in the final section of the article I draw some general conclusions about the nature of the relation between anthropology and linguistics and offer a conjecture as to its possible future development. Linguistic Anthropology as Institutionalized Subdiscipline Linguistic anthropology is one of several subdisciplines that have a recognized existence at least within the United States, as institutionalized in 1984 by the creation of various sections within the American Anthropological Association (aaa); it now has forty sections, most of which have their own journals. Besides linguistic anthropology, these include, for example, political and legal anthropology, psychological anthropology, and medical anthropology.2 [End Page 268] Before turning to the intellectual issues raised by the existence of subdisciplines of this kind I first provide some more details about the current institutional status of linguistic anthropology in relation to the other subfields of anthropology as reflected by the membership of various relevant sections of aaa. All members of aaa, in addition to belonging the association itself, are required to belong to at least one of the forty sections. The largest sections are the American Ethnological Society and the Society for Cultural Anthropology. This accurately reflects the institutional status of their associated (sub)disciplinary field of sociocultural anthropology, which is by far the predominant one in that the majority of faculty positions and courses in almost all anthropology departments are in that field, both in the United States and elsewhere. Table 1 shows the number of members in each of those two sections of aaa at five-year intervals from 1985 to 2010 and the number of members of the aaa section associated with linguistic anthropology—the Society for Linguistic Anthropology (sla).3 The fourth row shows the combined total of the American Ethnological Society and the Society for Cultural Anthropology, which can be taken as rough indicator of the interest in, or identification of aaa members with, sociocultural anthropology relative to linguistic anthropology.4 Based on the figures in table 1, table 2 shows the proportion of aaa members who belong to each of the three sections under discussion here and to aes and sca together. Figure 1 shows the trends inherent in both tables in the form of a graph. In relation to the issues of interdisciplinarity to be discussed in the rest of this article, two points to note are as follows: Since 1985 there has been a slow but steady rise both in sla membership and in the proportion of aaa members who belong to sla. Since 1995 there has been a steady narrowing of the gap between the combined membership of aes and sca and that of sla. Whereas in 1995 the ratio of members in aes + sca to sla was ca. 7.3 to 1, in 2010 it was ca. 4.7 to 1. Judging from the relative numbers of faculty positions and postgraduate students, the latter figure seems disproportional to the number of US anthropologists who would identify themselves primarily as linguistic anthropologists vs. identifying themselves primarily as sociocultural anthropologists. Why should [End Page 269] Click for larger view View full resolution Table 1. Number of members in various sections of the American Anthropological Association Click for larger view View full resolution Table 2. Proportion of AAA members who...

Methods for Carving Expanded Polytetrafluoroethylene Prostheses in Augmentation Rhinoplasty and Their Impact on Nose Shape

Sir:FigureProsthesis shape will directly impact postoperative nose aesthetics in augmentation rhinoplasty. This article reports methods of carving the prosthesis and their impact on nose shape. The commercial name of the expanded polytetrafluoroethylene used in our hospital operations was Tisuthes (Shanghai Suokang Medical Implants, Shanghai, People's Republic of China).1 Its dimensions were 70 × 15 × 8 mm. Low-lying noses were divided into three types: low nasion (type A), low nasal bridge (type B), and low nasal bridge and tip (type C) (Fig. 1, above). Prostheses were carved into a short willow shape, a long willow shape, or an L shape, respectively.Fig. 1: Three types of low-lying noses (low nasion, low nasal bridge, and low nasal bridge and tip) and the carving procedures to create the short willow-shaped, long willow-shaped, and L-shaped prostheses.For length (Fig. 1, second row), the starting point, A, was the horizontal line 3 to 4 mm above the midline between the eyebrows and eyes. The ending point, B, was the tangent point of the prosthesis and nasion skin for type A and B. For type C, it marked the junction of the facial vertical line of the columella-lobular angle and the prosthesis. A triangular section was cut from both sides of the prosthesis at point B to divide it into a long segment (used on the nasal bridge) and a short segment (used for the columella, approximately 10 mm). The width at the junction of the long and short segments was 3 to 5 mm. For the ventral surface (Fig. 1, third row), for type A, a triangular section was obliquely cut from both the cephalic end and nasal end of the ventral surface of the prosthesis to maximize the attachment between the ventral surface of the prosthesis and the nasal bridge. Type B was approached the same as type A. If there was a small bump on the nasal bridge, a hole was made at the corresponding spot on the ventral surface of the prosthesis. For type C, the long segment is the same as type B. The short segment of the prosthesis was obliquely trimmed from point B and varied from 1 to 3 mm thick beyond that point. For width (Fig. 1, fourth row), for types A and B, a wedge was cut from both sides of the prosthesis to achieve the desired width, which was approximately 12 mm for male patients and 10 mm for female patients. The width at point B was approximately 5 mm. For type C, the long segment is the same as for type B. The short segment was gradually tapered to 1 mm or to have an angle near its tip. For the dorsal surface (Fig. 1, fifth row), for type A, a 135- to 140-degree angle was carved at point A of the prosthesis dorsal surface, which was trimmed to a desired thickness of no more than 3 mm for type A. For type B, the thickness is usually no more than 8 mm for male patients and 6 mm for female patients. For type C, the long segment is the same as for type B. The prosthesis was cut open transversely at the superficial layer of the junction of the long and short segments. The short segment was then folded ventrally to form an L-shaped prosthesis. The impact of each factor on nose shape is summarized in Table 1.1–4Table 1: The Impact of Length, Width, Dorsal Surface, and Ventral Surface on Nose ShapeXudong Zhang, M.D. Qinjian Peng, M.D. Yongcheng Xu, M.D. Department of Cosmetic Surgery, Beijing Huangsi Aesthetical Surgery Hospital, Beijing, People's Republic of China DISCLOSURE The authors have no financial interest to declare in relation to the content of this article.

ERRATA

Sanz-Lázaro et al. have discovered errors in two of the figures included in their article (“Effect of temperature on biogeochemistry of marine organic-enriched systems: implications in a global warming scenario”), published in the October 2011 issue (Ecological Applications 21:2664–2677). The top row of panels in Fig. 3 lacked units for SO42– in the published version; the units should have been specified as mmol/L for all three temperatures. Also, the units for the horizontal axis in Fig. 4 were incorrectly given as mmol/cm3; the correct units for AVS and CRS are μmol/cm3. These errors were apparently introduced by our Graphics Department during preparation of figures for publication. We apologize to the authors and to our readers. Brown et al. have discovered errors in Table 2 of their paper (“How long can fisheries management delay action in response to ecosystem and climate change?”) in the January 2012 issue (Ecological Applications 22:298–310). Two entries in Table 2 may be incorrectly interpreted. The cause under the third row (“North Pacific Minke whales”) should read “scientific uncertainty led to a long process to develop a management scheme, during which catch limits for commercial whaling were zero”. In addition, the cause in the fourth row (“Whales”) should read “time period required between reviews of management strategy by the International Whaling Commission; this time period was selected using simulations and shown to be adequate”.

A single flexible tube in a rigid array as a model for fluidelastic instability in tube bundles

Fluidelastic instability is considered the most critical flow induced vibration mechanism in tube and shell heat exchangers, and as such has received the most attention. The present study examines the concept of using a single flexible tube in a rigid array for predicting fluidelastic instability. The experimental work published in the open literature involving the use of a single flexible tube in a rigid array is critically reviewed. Based on this, an experiment is designed to facilitate precise control of the system parameters and to study tube response at different locations in the array. Experiments were conducted using a fully flexible array as well as a single flexible tube in the same rigid array. It is found that a single flexible tube located in the third row of a rigid parallel triangular array becomes fluidelastically unstable at essentially the same threshold as for the fully flexible array. However, when the single flexible tube is located in the first, second, fourth, or fifth rows, no instability behavior is detected. Thus, tube location inside the array significantly affects its fluidelastic stability behavior when tested as a single flexible tube in a rigid array. It is concluded that, in general, fluidelastic instability in tube arrays is caused by a combination of the damping and stiffness mechanisms. In certain cases, a single flexible tube in a rigid array will become fluidelastically unstable and provide a useful model for fundamental research and developing physical insights. However, it must be cautioned that this behavior is a special case and not generally useful for determining the stability limit of tube arrays.

Erratum to: Ungersma et al., vessel imaging with viable tumor analysis for quantification of tumor angiogenesis. Magn Reson Med 2010;63:1637–1647

Due to a data processing error, the reported Q values in Figs. 3b and 5d and the Q parameter maps in Figs. 4 and 7 of the original manuscript were incorrect. The data processing error only affected the reported Q values in the original manuscript; all other results were not affected. The corrected Q plots and figures are provided below. The linear correlation between Q3/D and histological vessel density does not reach significance (R2 = 0.23, P = 0.06) (Fig. 3b). Representative Day 2 Q maps from one tumor in each treatment group are shown in Fig. 4. The change in Q (Fig. 5d) for the anti-VEGF group did not differ significantly from the changes observed in the control group (P = 0.06), although the anti-VEGF Day 2 Q estimates were significantly reduced relative to pre-treatment values (32 ± 4%, P < 0.0001) and relative to the control group at Day 2 (P < 0.005). The change in Q (Fig. 5d) for the anti-NRP1B group did not differ significantly from the changes observed in the control group (P = 0.42). Anti-NRP1B Day 2 Q estimates were significantly reduced relative to pre-treatment values (20 ± 6%, P < 0.05), but not relative to the control group at Day 2 (P = 0.10). Pre- and post-treatment Q parametric maps for the anti-VEGF group are shown in Fig. 7 (only the fourth row of the original figure is shown). A one-to-one comparison of the mean Q3/D (with the assumption that D ∼ 1.0 μm2/ms) for viable tumor to the histological vessel density (number of vessels/viable tissue area) shows a linear correlation that does not reach significance (R2 = 0.23, P = 0.06). Representative Day 2 Q maps from one tumor in each treatment group. Effects of anti-VEGF and anti-NRP1B treatment on the Q parameter: change from pre-treatment to 48 hours post-treatment. Representative Q maps from a single tumor treated with anti-VEGF, before treatment (left column) and 48 hours post-treatment (right column).

Erratum to “An Obesity-Related FTO Variant and the Risk of Preeclampsia in a Finnish Study Population”

Erratum to “An Obesity-Related <i>FTO</i> Variant and the Risk of Preeclampsia in a Finnish Study Population”

Solution enthalpy of hydrogen in fourth row elements: Systematic trends derived from first principles

Based on first-principles calculations, we identify a master curve for the solution enthalpy of H in fourth row elements including all $3d$ transition metals. Assuming nonmagnetic fcc crystal structures, we find two different classes of materials with either the octahedral or the tetrahedral interstitial site being preferred by hydrogen. An interaction radius for H in octahedral site of $\ensuremath{\approx}$0.7 \AA{} ($\ensuremath{\approx}0.4$\AA{} for H in tetrahedral site) turns out to be a characteristic value for which the chemical interaction energy has an optimum for all studied elements.

Accurate spin–orbit and spin–other-orbit contributions to the g-tensor for transition metal containing systems

In this paper an overview is presented of several approximations within Density Functional Theory (DFT) to calculate g-tensors in transition metal containing systems and a new accurate description of the spin-other-orbit contribution for high spin systems is suggested. Various implementations in a broad variety of software packages (ORCA, ADF, Gaussian, CP2K, GIPAW and BAND) are critically assessed on various aspects including (i) non-relativistic versus relativistic Hamiltonians, (ii) spin-orbit coupling contributions and (iii) the gauge. Particular attention is given to the level of accuracy that can be achieved for codes that allow g-tensor calculations under periodic boundary conditions, as these are ideally suited to efficiently describe extended condensed-phase systems containing transition metals. In periodic codes like CP2K and GIPAW, the g-tensor calculation schemes currently suffer from an incorrect treatment of the exchange spin-orbit interaction and a deficient description of the spin-other-orbit term. In this paper a protocol is proposed, making the predictions of the exchange part to the g-tensor shift more plausible. Focus is also put on the influence of the spin-other-orbit interaction which becomes of higher importance for high-spin systems. In a revisited derivation of the various terms arising from the two-electron spin-orbit and spin-other-orbit interaction (SOO), new insight has been obtained revealing amongst other issues new terms for the SOO contribution. The periodic CP2K code has been adapted in view of this new development. One of the objectives of this study is indeed a serious enhancement of the performance of periodic codes in predicting g-tensors in transition metal containing systems at the same level of accuracy as the most advanced but time consuming spin-orbit mean-field approach. The methods are first applied on rhodium carbide but afterwards extended to a broad test set of molecules containing transition metals from the fourth, fifth and sixth row of the periodic table. The set contains doublets as well as high-spin molecules.

Turbulent Flow Inside and Above a Wind Farm: A Wind-Tunnel Study

Wind-tunnel experiments were carried out to better understand boundary layer effects on the flow pattern inside and above a model wind farm under thermally neutral conditions. Cross-wire anemometry was used to characterize the turbulent flow structure at different locations around a 10 by 3 array of model wind turbines aligned with the mean flow and arranged in two different layouts (inter-turbine separation of 5 and 7 rotor diameters in the direction of the mean flow by 4 rotor diameters in its span). Results suggest that the turbulent flow can be characterized in two broad regions. The first, located below the turbine top tip height, has a direct effect on the performance of the turbines. In that region, the turbulent flow statistics appear to reach equilibrium as close as the third to fourth row of wind turbines for both layouts. In the second region, located right above the first one, the flow adjusts slowly. There, two layers can be identified: an internal boundary layer where the flow is affected by both the incoming wind and the wind turbines, and an equilibrium layer, where the flow is fully adjusted to the wind farm. An adjusted logarithmic velocity distribution is observed in the equilibrium layer starting from the sixth row of wind turbines. The effective surface roughness length induced by the wind farm is found to be higher than that predicted by some existing models. Momentum recovery and turbulence intensity are shown to be affected by the wind farm layout. Power spectra show that the signature of the tip vortices, in both streamwise and vertical velocity components, is highly affected by both the relative location in the wind farm and the wind farm layout.

Surgical Procedure for Transplanting Artificial Nerve Conduits for Peripheral Nerve Regeneration

Surgical Procedure for Transplanting Artificial Nerve Conduits for Peripheral Nerve Regeneration

DISAPPEARANCE RATE OF PRAZIQUANTEL-CONTAINING BAIT AROUND VILLAGES AND SMALL TOWNS IN SOUTHERN BAVARIA, GERMANY

In recent years, the red fox (Vulpes vulpes) has increasingly occupied urban areas in central Europe. Meanwhile, prevalence of infection in foxes with the small fox tapeworm (Echinococcus multilocularis) has increased, thereby increasing the human risk of infection with the parasite, which causes alveolar echinococcosis. Baiting strategies to counteract E. multilocularis have been implemented in cities and the open countryside, but there are few data on the situation in villages and small towns (<10,000 inhabitants). We recorded disappearance rates of praziquantel-containing bait within villages and small towns and on settlement edges for 7 days after distribution. Disappearance rates were 89.2% in villages, 88.8% in small towns, and 91.8% in settlement edges. More than 75% of the bait was consistently taken within the first three nights. There were no significant differences in disappearance rates between years or among seasons (Cox proportional hazard model). The survival time of the bait in small towns (P=0.021) and villages (P=0.026) depended on the zone (zone 1, first row of houses bordering on open countryside; zone 2, second to fourth rows, zone 3; beyond the fifth row) in which bait was distributed. In villages, the probability of bait being eaten in zone 1 was 119% higher than it was in zone 3 (P=0.007). In small towns, the probability was 60% higher (P=0.006).

Atomic Scale Analysis of Ultrathin SiO2 Films Prepared on TiO2(100) Surfaces

Rutile titanium dioxide (TiO2) (100) surfaces covered by silicon oxide (SiO2) ultrathin films were examined by X-ray photoelectron spectroscopy (XPS), low energy electron diffraction (LEED), and frequency modulation atomic force microscopy (FM-AFM) techniques. The SiO2 films were fabricated on TiO2 crystals by annealing in a quartz case which was used as a SiO2 source. The amount of Si increased with annealing time, and a (3 × 4) LEED pattern was observed on surfaces with the XPS peak intensity ratio of Si 2p to O 1s of TiO2 larger than 0.023. FM-AFM observation in pure water showed that the (3 × 4) surface consists of atomically flat terraces. Within the terraces, rows which extend in the [001] direction were observed. Every fourth row appeared brighter, consistent with the ×4 periodicity in the [010] direction observed in LEED. Models where rutile SiO2 units are accumulated on the TiO2(100) surface via rutile Ti1−xSixO2 units are consistent with the results.

Input vector optimization of feed-forward neural networks for fitting ab initio potential-energy databases

The variation in the fitting accuracy of neural networks (NNs) when used to fit databases comprising potential energies obtained from ab initio electronic structure calculations is investigated as a function of the number and nature of the elements employed in the input vector to the NN. Ab initio databases for H(2)O(2), HONO, Si(5), and H(2)C[Double Bond]CHBr were employed in the investigations. These systems were chosen so as to include four-, five-, and six-body systems containing first, second, third, and fourth row elements with a wide variety of chemical bonding and whose conformations cover a wide range of structures that occur under high-energy machining conditions and in chemical reactions involving cis-trans isomerizations, six different types of two-center bond ruptures, and two different three-center dissociation reactions. The ab initio databases for these systems were obtained using density functional theory/B3LYP, MP2, and MP4 methods with extended basis sets. A total of 31 input vectors were investigated. In each case, the elements of the input vector were chosen from interatomic distances, inverse powers of the interatomic distance, three-body angles, and dihedral angles. Both redundant and nonredundant input vectors were investigated. The results show that among all the input vectors investigated, the set employed in the Z-matrix specification of the molecular configurations in the electronic structure calculations gave the lowest NN fitting accuracy for both Si(5) and vinyl bromide. The underlying reason for this result appears to be the discontinuity present in the dihedral angle for planar geometries. The use of trigometric functions of the angles as input elements produced significantly improved fitting accuracy as this choice eliminates the discontinuity. The most accurate fitting was obtained when the elements of the input vector were taken to have the form R(ij) (-n), where the R(ij) are the interatomic distances. When the Levenberg-Marquardt procedure was modified to permit error minimization with respect to n as well as the weights and biases of the NN, the optimum powers were all found to lie in the range of 1.625-2.38 for the four systems studied. No statistically significant increase in fitting accuracy was achieved for vinyl bromide when a different value of n was employed and optimized for each bond type. The rate of change in the fitting error with n is found to be very small when n is near its optimum value. Consequently, good fitting accuracy can be achieved by employing a value of n in the middle of the above range. The use of interparticle distances as elements of the input vector rather than the Z-matrix variables employed in the electronic structure calculations is found to reduce the rms fitting errors by factors of 8.86 and 1.67 for Si(5) and vinyl bromide, respectively. If the interparticle distances are replaced with input elements of the form R(ij) (-n) with n optimized, further reductions in the rms error by a factor of 1.31 to 2.83 for the four systems investigated are obtained. A major advantage of using this procedure to increase NN fitting accuracy rather than increasing the number of neurons or the size of the database is that the required increase in computational effort is very small.

Spin–orbit splittings in the valence states of XH (X=K, Ca, Ga, Ge, As, Se, and Br) by the effective Hamiltonian approach

Abstract One advantage of the effective valence shell Hamiltonian method is that the spin–orbit coupling energies of all valence states, regardless of the number of valence electrons, are simultaneously determined with a similar accuracy from a single computation of the effective spin–orbit coupling operator. To assess the accuracy of the effective Hamiltonian method extensively, calculations are performed for the spin–orbit splittings in the valence states of fourth row diatomic monohydrides and their ions. The calculated spin–orbit splittings are generally in good agreement with known experiments or computations. Furthermore, the spin–orbit splittings of valence states, for which neither experiment nor theory is available, are predicted.

Variability in the number of tooth rows in the pharyngeal dentition ofBarbus intermedius(Teleostei; Cyprinidae): genetic, hormonal and environmental factors

Summary The variability of pharyngeal dentition in a natural population of B. intermedius and effects of genetic, hormonal and environmental factors on the number of tooth rows in the pharyngeal dentition in offspring from wild-caught parents have been investigated. It was revealed that: (i) about 10% of fish from natural population have four-rowed dentition instead of three-rowed dentition characteristic for this species; (ii) the presence of the additional tooth row is not an abnormality of tooth replacement since it occurs symmetrically on both sides; (iii) occurrence of the fourth row of teeth is heritable since laboratory-reared offspring from parents with four-rowed dentition have the same dentition. Even if one of the parents had four-rowed dentition the percentage of four-rowed individuals in the progeny was significantly higher than in progeny from parents with normal (three rowed) dentition; (iv) the number of tooth rows appears to be hormonally controlled: high levels of thyroid hormone result in a decrease in the number of tooth rows to two. In contrast, deficiency of this hormone results in an increase to four rows; (v) no differences in the number of tooth rows were found in fish reared under 17°C, 24°C, 30°C and room temperature (20–26°C).

Phase-sensitive black-blood coronary vessel wall imaging

Black-blood MR coronary vessel wall imaging may become a powerful tool for the quantitative and noninvasive assessment of atherosclerosis and positive arterial remodeling. Although dual-inversion recovery is currently the gold standard, optimal lumen-to-vessel wall contrast is sometimes difficult to obtain, and the time window available for imaging is limited due to competing requirements between blood signal nulling time and period of minimal myocardial motion. Further, atherosclerosis is a spatially heterogeneous disease, and imaging at multiple anatomic levels of the coronary circulation is mandatory. However, this requirement of enhanced volumetric coverage comes at the expense of scanning time. Phase-sensitive inversion recovery has shown to be very valuable for enhancing tissue-tissue contrast and for making inversion recovery imaging less sensitive to tissue signal nulling time. This work enables multislice black-blood coronary vessel wall imaging in a single breath hold by extending phase-sensitive inversion recovery to phase-sensitive dual-inversion recovery, by combining it with spiral imaging and yet relaxing constraints related to blood signal nulling time and period of minimal myocardial motion.

Relativistic contracted Gaussian-type basis functions for atoms K through Xe

For 36 atoms from K to Xe, compact relativistic Gaussian-type function basis sets are developed in a segmented contraction form: ( 843 2 / 74 / 7 ) for the third row atoms and ( 843 3 / 743 / 74 ) for the fourth row atoms. Spin-free relativistic effects are considered through the third-order Douglas–Kroll approximation. The present basis sets are tested for all-electron calculations of four homo- and 12 heteronuclear diatomics in their ground states. The calculated spectroscopic constants are in good agreement with the experimental values.