Computed tomography and magnetic resonance diagnosis of variations in the anatomical location of the major salivary glands in 1680 dogs and 187 cats

During assessment of routine clinical magnetic resonance imaging (MRI) of the heads of dogs, variations in the location of mandibular and zygomatic salivary glands (SGs) were observed incidentally. The aims of this retrospective study were to describe anatomical variations of the major SGs found on MRI and computed tomography (CT) studies of the head in dogs and cats and to investigate possible clinical relevancy. No anatomical variation of the SGs was seen in cats, but in dogs, although variation of the parotid SG was not identified, that of the mandibular SG was found in 33/1680 animals (2%), either unilaterally (6/33 right-sided, 13/33 left-sided) or bilaterally (14/33). The Border terrier breed (19/33, 58%) was over-represented. Each atypically located mandibular SG was positioned medial to the digastric muscle and rostral to the retropharyngeal lymph node. The sublingual glands were difficult to delineate from the mandibular glands. Anatomical variation of one zygomatic gland (3/4 left-sided) was identified in four small-breed dogs (0.2%). Each atypically located zygomatic gland was tilted at the ventrorostral aspect of the masseter muscle underneath the skin surface. MRI and CT characteristics were not different between typically and atypically located SGs. None of the dogs had clinical signs related with SG disease. It was concluded that, with suspected breed predispositions, incidental unilateral or bilateral anatomical variations of mandibular and zygomatic SGs can be encountered in dogs and an awareness of these possible variations may be important in pre-surgical planning

Localizing the Latent Structure Canonical Uncertainty: Entropy Profiles for Hidden Markov Models

This report addresses state inference for hidden Markov models. These models rely on unobserved states, which often have a meaningful interpretation. This makes it necessary to develop diagnostic tools for quantification of state uncertainty. The entropy of the state sequence that explains an observed sequence for a given hidden Markov chain model can be considered as the canonical measure of state sequence uncertainty. This canonical measure of state sequence uncertainty is not reflected by the classic multivariate state profiles computed by the smoothing algorithm, which summarizes the possible state sequences. Here, we introduce a new type of profiles which have the following properties: (i) these profiles of conditional entropies are a decomposition of the canonical measure of state sequence uncertainty along the sequence and makes it possible to localize this uncertainty, (ii) these profiles are univariate and thus remain easily interpretable on tree structures. We show how to extend the smoothing algorithms for hidden Markov chain and tree models to compute these entropy profiles efficiently.Comment: Submitted to Journal of Machine Learning Research; No RR-7896 (2012

Sudden To Adiabatic Transition in Beta Decay

We discuss effects in beta decays at very low beta energies, of the order of the kinetic energies of atomic electrons. As the beta energy is lowered the atomic response changes from sudden to adiabatic. As a consequence, the beta decay rate increases slightly and the ejection of atomic electrons (shake off) and subsequent production of X rays is turned off. We estimate the transition energy and the change in decay rate. The rate increase is largest in heavy atoms, which have a small Q value in their decay. The X ray switch-off is independent of Q value.Comment: 6 pages LaTe

Analysis of dynamical corrections to baryon magnetic moments

We present and analyze QCD corrections to the baryon magnetic moments in terms of the one-, two-, and three-body operators which appear in the effective field theory developed in our recent papers. The main corrections are extended Thomas-type corrections associated with the confining interactions in the baryon. We investigate the contributions of low-lying angular excitations to the moments quantitatively and show that they are completely negligible. When the QCD corrections are combined with the non-quark model contributions of the meson loops, we obtain a model which describes the moments within a mean deviation of 0.04 $\mu_N$. The nontrivial interplay of the two types of corrections to the quark-model moments is analyzed in detail, and explains why the quark model is so successful. In the course of these calculations, we parametrize the general spin structure of the $j={1/2}^+$ baryon wave functions in a form which clearly displays the symmetry properties and the internal angular momentum content of the wave functions, and allows us to use spin-trace methods to calculate the many spin matrix elements which appear in the expressions for the moments. This representation may be useful elsewhere.Comment: 32 pages, 3 figures, submitted to Phys. Rev.

Time resolved fission in metal clusters

We explore from a theoretical point of view pump and probe (P&P) analysis for fission of metal clusters where probe pulses are generalized to allow for scanning various frequencies. We show that it is possible to measure the time the system needs to develop to scission. This is achieved by a proper choice of both delay and frequency of the probe pulse. A more detailed analysis even allows to access the various intermediate stages of the fission process.Comment: 4 pages, 4 figure

Remarks on the Permian-Triassic transition in Central and Eastern Lombardy (Southern Alps, Italy)

The main lithological and petrographical characteristics of the Permian-Lower Triassic Orobic and Brescian successions in central and eastern Lombardy are briefl y recorded, especially with regard to the units cropping out below and above the P-T boundary. The lower formation is represented by the Verrucano Lombardo, which consists of continental, fluvial red clastics, barren of fossils, generally Late Permian (Lopingian) in age, whereas the overlying Servino Formation, which is represented by well-bedded clastic and carbonate polychrome sediments, generally rich in fossils, pertains to the Early Triassic (Induan-Olenekian). The sequences of the two above-mentioned areas differ at least in part, as proof of their regional division, probably because of an inherited paleotopography and syntectonic activity. Taking into account the units bracketing the P-T boundary, which represents the real topic of this work, the Verrucano Lombardo of the Orobic Alps is paraconformably covered by the conglomerates and sandstones of the Prato Solaro Member in the lower part of the Servino Formation, cropping out extensively, although discontinuously, from the eastern side of Lake Como to the upper Scalve Valley in the Camonica region. The shape of some quartz rock fragments, derived from the Variscan crystalline basement and its Upper Carboniferous siliciclastic cover, has been interpreted as due to relatively coeval aeolian activity, and testifi es to an arid climatic “event” probably late Dienerian-early Smithian in age. In contrast, in the Brescia province, the onset of the Servino is made up of wave and current rippled, fi ne clastics, 1-2 m thick, and a typical horizon of oolitic dolostones (“Praso Limestone” Auct.), continuous from the lower Camonica Valley to the western Trentino. This unit could laterally correlate towards east, in the eastern South-Alpine segment, with the famous oolitic Tesero Member at the base of the Werfen Formation of the Dolomitic and Carnic Alps. In the Brescian Prealps, the above oolitic deposits crop out below some Claraia beds yielding forms common to those present in the Siusi Member of the Dolomites, generally attributed to late Griesbachian-early Dienerian times. Their age could be ascribed to a slightly older Griesbachian, i.e. to early Induan. Therefore, the P-T boundary in central and eastern Lombardy seems substantially located between the fi nal part of the Permian and the very base of the respective Triassic successions, temporally and spatially ranging in different ways and generally affected by non-depositional and perhaps tectonic processes. In our opinion, however, the duration of the gap, based on correlations with the well-documented stratigraphical studies recently carried out in the nearby Dolomitic area and other European regions, should be considered as slightly longer than previously recognized: the maximum gap could be estimated at about 3-4 Ma. As a consequence, we thus point out that the Servino Formation of the Brescian Alps rests, itself, paraconformably on the Verrucano Lombardo red beds, even if the P-T gap was probably less for correlation with the well-known Dolomites sections. At the end of the paper, for a more comprehensible understanding of the late- to post-Variscan geological scenario, is a tentative synthesis of the regional evolution.Se resumen las principales características litológicas y petrológicas de las sucesiones Oróbica y Bresciana del Pérmico y Triásico Inferior del este de Lombardía, especialmente las referidas a aquellas unidades que afl oran por encima y por debajo del límite P-T. La formación inferior está representada por el “Verrucano Lombardo”, que está constituido de sedimentos continentales clásticos de color rojo, de origen fluvial y sin fósiles y que muestran generalmente una edad Pérmico Superior (Lopingiense), mientras que la unidad inmediatamente superior, Formación Servino, representada por sedimentos bien estratifi cados, clásticos y carbonáticos, con abundantes fósiles y diferentes colores, es de edad Triásico Inferior (Induense-Olenekian). Las sucesiones de las dos áreas arriba mencionadas difieren entre sí, debido, entre otros motivos, a aquellos ligados a las características paleogeográfi cas y tectónicas propias de las zonas en las que afloran. El Verrucano Lombardo, en los afloramientos de los Alpes Oróbicos, que aflora extensivamente aunque de forma discontinua desde la parte este del lago Como hasta la parte alta del valle Scalve, en la región Carmónica, se sitúa, mediante una paraconformidad, bajo los conglomerados y areniscas del Miembro Prato Solaro, pertenecientes a la parte inferior de la Formación Servino. La forma de algunos fragmentos de roca, derivados del basamento cristalino varisco, así como los sedimentos siliciclásticos del Carbonífero Superior que los cubren, han sido relacionadas con una actividad de tipo eólica, testificando un evento climático de tipo árido, probablemente de edad Dieneriense superior-Smithiense inferior. En contraste, en la provincia de Brescia, la Formación Servino está constituida por sedimentos clásticos con ripples de oscilación y corriente, de tamaño de grano fino, constituyendo un espesor de 1-2 m y un nivel típico de dolomías oolíticas (“Praso Limestone” Auct.), que aparece desde la parte inferior del valle de Camonica hasta el oeste Trentino. Hacia el oeste, en el segmento este de los Alpes Meridionales, esta unidad podría correlacionarse lateralmente con el Miembro Tesero, de carácter oolítico, de la base de la Formación Werfen de los Alpes Dolomíticos y Cárnicos. En los Prealpes Brescianos, los depósitos oolíticos anteriormente mencionados afloran por debajo de algunas capas con Claraia, mostrando formas parecidas a las existentes del actual Miembro Siusi de los Dolomitas, generalmente atribuidos a una edad Griesbachiense-Dineriense inferior. Su edad podría ser ligeramente anterior a Griesbachiense, i.e. Induense inferior. Así, el límite P-T en el centro y este de Lombardía, estaría básicamente estar localizado entre la parte final de los sedimentos considerados pérmicos y aquellos de la parte más baja de los considerados Triásico Inferior, aunque con ciertas variaciones temporales y espaciales, variando en función de los procesos no deposicionales y, posiblemente, tectónicos. En nuestra opinión y, basándonos en correlaciones bien documentadas estudios estratigráficos llevados a cabo en los Dolomitas y en otras regiones europeas, prolongación en el tiempo de esta etapa en la que falta registro sedimentario podría ser considerada como ligeramente más larga de lo inicialmente reconocido: esta etapa podría ser considerada en torno a 3-4 Ma. Como consecuencia, consideramos que la Formación Servino de los Alpes Brescianos, como tal, paraconformable sobre las capas rojas del Verrucano Lombardo incluso aunque el vacío sedimentario de la transición P-T en esta zona fuese menor que el de la zona correlacionable y bien conocida de las secciones de los Dolomitas

Stability of the Zagreb Carnegie-Mellon-Berkeley model

In ref. [1] we have used the Zagreb realization of Carnegie-Melon-Berkeley coupled-channel, unitary model as a tool for extracting pole positions from the world collection of partial wave data, with the aim of eliminating model dependence in pole-search procedures. In order that the method is sensible, we in this paper discuss the stability of the method with respect to the strong variation of different model ingredients. We show that the Zagreb CMB procedure is very stable with strong variation of the model assumptions, and that it can reliably predict the pole positions of the fitted partial wave amplitudes.Comment: 25 pages, 12 figures, 19 table

Reply to discussion on the article “Remarks on the Permian- Triassic transition in Central and Eastern Lombardy (Southern Alps, Italy)” by G. Cassinis, M. Durand and A. Ronchi

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Metal-Free Modified Boron Nitride for Enhanced CO2 Capture

Porous boron nitride is a new class of solid adsorbent with applications in CO2 capture. In order to further enhance the adsorption capacities of materials, new strategies such as porosity tuning, element doping and surface modification have been taken into account. In this work, metal-free modification of porous boron nitride (BN) has been prepared by a structure directing agent via simple heat treatment under N2 flow. We have demonstrated that textural properties of BN play a pivotal role in CO2 adsorption behavior. Therefore, addition of a triblock copolymer surfactant (P123) has been adopted to improve the pore ordering and textural properties of porous BN and its influence on the morphological and structural properties of pristine BN has been characterized. The obtained BN-P123 exhibits a high surface area of 476 m2/g, a large pore volume of 0.83 cm3/g with an abundance of micropores. More importantly, after modification with P123 copolymer, the capacity of pure CO2 on porous BN has improved by about 34.5% compared to pristine BN (2.69 mmol/g for BN-P123 vs. 2.00 mmol/g for pristine BN under ambient condition). The unique characteristics of boron nitride opens up new routes for designing porous BN, which could be employed for optimizing CO2 adsorption

Deformation of grain boundaries in polar ice

The ice microstructure (grain boundaries) is a key feature used to study ice evolution and to investigate past climatic changes. We studied a deep ice core, in Dome Concordia, Antarctica, which records past mechanical deformations. We measured a "texture tensor" which characterizes the pattern geometry and reveals local heterogeneities of deformation along the core. These results question key assumptions of the current models used for dating