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An eight-year-old castrated male, 45 kg labrador retriever presented for evaluation of a two-week history of cough and tachypnoea. Echocardiography revealed an approximately 10 cm heart base mass, which extended to the right atrioventricular junction, causing compression of both the right atrium and ventricle resulting in right-sided congestive heart failure (abdominal effusion). Cytology of the mass was consistent with a neuroendocrine carcinoma. Given the location and description, a chemodectoma or ectopic thyroid carcinoma was suspected. The patient was treated with toceranib phosphate and famotidine. At the follow-up appointment four weeks later, the right heart compression had resolved due to a clinically significant reduction in the size of the mass. The patient was prescribed furosemide and enalapril to treat right-sided congestive heart failure. When considering treatment options for haemodynamically significant heart base masses, treatment with toceranib phosphate may result in rapid clinical benefit. [ABSTRACT FROM AUTHOR]

A systematic study of the atomic and electronic structure of the γ-TiAl(111)/α-Al2O3(0001) interface with intermediate metal (Nb, Mo, Ni, Re) and oxide (Nb2O5, MoO3) layers has been performed by the projector augmented-wave method within density functional theory. The work of separation at the interfaces in dependence on the cleavage plane has been calculated. It is shown that a high adhesion energy obtained at the interface with the O-terminated α-Al2O3 is decreased at the γ-TiAl/Me interface but it remains enough high at the Me/α-Al2O3(0001)O interface due to a large ionic contribution to the chemical bonding. The influence of formation of intermediate impurity oxide layers on the adhesive properties of the alloy/oxide interface is discussed as well. The obtained results indicate that the fracture will occur inside the impurity oxide or its interface with the alloy. [ABSTRACT FROM AUTHOR]

The Fifth Neurocritical Care Research Network (NCRN) Conference held in Boca Raton, Florida, in September of 2018 was devoted to challenging the current status quo and examining the role of the Neurocritical Care Society (NCS) in driving the science and research of neurocritical care. The aim of this in-person meeting was to set the agenda for the NCS's Neurocritical Care Research Central, which is the overall research arm of the society. Prior to the meeting, all 103 participants received educational content (book and seminar) on the 'Blue Ocean Strategy®,' a concept from the business world which aims to identify undiscovered and uncontested market space, and to brainstorm innovative ideas and methods with which to address current challenges in neurocritical care research. Three five-member working groups met at least four times by teleconference prior to the in-person meeting to prepare answers to a set of questions using the Blue Ocean Strategy concept as a platform. At the Fifth NCRN Conference, these groups presented to a five-member jury and all attendees for open discussion. The jury then developed a set of recommendations for NCS to consider in order to move neurocritical care research forward. We have summarized the topics discussed at the conference and put forward recommendations for the future direction of the NCRN and neurocritical care research in general. [ABSTRACT FROM AUTHOR]

The atomic and electronic structure of the interfaces between metals with body-centered cubic (bcc) and face-centered cubic (fcc) structures and zirconium dioxide is studied systematically using the ab initio methods of the electron density functional theory (DFT). It is shown that high adhesion properties can be attained at the nonstoichiometric polar Me(001)/ZrO(001) interface with bcc metals from the middle of the 4d-5d periods (Mo, Ta, W, and Nb). Charge transfer from the metal to the oxide substrate ensures the strong ionic chemical bond on the metal-ceramic interfaces. The structural and electronic factors responsible for lowering of adhesion at differently oriented interfaces are analyzed. It is shown that a decrease of adhesion at the (110) nonpolar stoichiometric interface is due to an increase in the interfacial spacing as well as a decrease in the number of metal-oxygen bonds. The effect of doping with oxides (CaO, MgO, and YO) stabilizing zirconium dioxide at low temperatures on the adhesion energy at the Me(001)/ZrO(001) interface is analyzed. [ABSTRACT FROM AUTHOR]

U-Pb geochronology and detailed field mapping has resulted in a new subdivision of the Kamiskotia Volcanic Complex into Lower and Upper Kamiskotia strata with a 3.5-m.y. volcanic hiatus between the two. The hiatus is interpreted as an unconformity, in common with newly recognized unconformities throughout the green-stone belt. The Genex, and other volcanogenic massive sulfide (VMS) deposits in the area, occur within the Upper Kamiskotia strata. Volcanic facies mapping and reconstruction indicate that the Genex VMS deposit formed within a volcanic graben where synvolcanic mafic and intermediate sills and dikes, with peperitic and locally pillowed contacts, define a proximal volcanic vent area. Sulfide mineralization at Genex occurs in three zones, the first hosted in pillow breccia and hyaloclastite, the second occurring at the contact between felsic tuff and an intermediate intrusion, and the third hosted within the intermediate intrusion. The mineralization represents subsea-floor replacement sulfides localized within zones of higher primary permeability. Although the synvolcanic mafic intrusions are not directly related to the Genex VMS mineralization they are indicative of a high heat-flow thermal regime. The synvolcanic faults that controlled the emplacement of synvolcanic dikes also provided conduits for the hydrothermal fluids responsible for the mineralization and alteration at Genex. This high-level mafic dike and sill complex was previously correlated with the upper zone of the Kamiskotia Gabbroic Complex but is now interpreted to be younger and correlative with the Upper Kamiskotia Volcanic Complex. New geochronological data also indicate that the Kamiskotia Gabbroic Complex is older than the VMS-hosting Upper Kamiskotia strata and was emplaced into the Lower Kamiskotia Volcanic Complex. This negates the possibility, of a genetic relationship between the Genex and other Kamiskotia VMS deposits within the Kamiskotia Gabbroic Complex. The small size of the synvolcanic intrusions indicates that they were also not the heat source for the Genex hydrothermal alteration system. However, their spatial coincidence suggests that this part of the Kamiskotia Volcanic Complex was the focus of long-lived intrusive activity and high heat flow that defined a thermal corridor encompassing the VMS deposits in the Kamiskotia Volcanic Complex. [ABSTRACT FROM AUTHOR]

POEMS syndrome is a disorder characterized by polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes. Castleman's disease is a rare lymphoproliferative disorder that can be present in patients with POEMS syndrome. Previous case reports have documented the association between POEMS syndrome and arterial and venous thromboses of the coronary and lower limb arteries. However, only 3 patients have ever been described with POEMS syndrome, Castleman's disease, and stroke. Two additional patients with this combination of disorders are reported herein. We suspect that the strokes are a result of a possible intracranial vasculopathic process.Copyright © 2007 by Elsevier Inc. [ABSTRACT FROM AUTHOR]

Al diffusion in decagonal Al–Ni–Co and Al–Cu–Co quasicrystals is investigated by molecular dynamics simulations. Results obtained with newly developed embedded-atom method potentials are compared with our previous work with effective pair potentials. With both types of potential, strong aluminium diffusion is observed above two-thirds of the melting temperature, and the general behaviours of the system are quite similar. The diffusion constant is measured as a function of temperature and pressure, and the activation enthalpies and activation volumes are determined from the resulting Arrhenius plot. For a number of important diffusion processes, the energy barriers are determined with molecular statics simulations. The qualitative behaviour of the dynamics is also confirmed by ab-initio simulations. [ABSTRACT FROM AUTHOR]

The atomic dynamics of decagonal Al-Ni-Co and Al-Cu-Co quasicrystals is investigated by molecular dynamics simulations. Depending on the local environments, the mobility of the atoms varies greatly from site to site. Above two thirds of the melting temperature, a large fraction of the aluminium atoms become so mobile, that their diffusion can be measured directly in the simulation. As aluminium diffusion is hard to access experimentally, molecular dynamics simulations therefore provide a unique way to study aluminium diffusion in these complex systems. [ABSTRACT FROM AUTHOR]

Background: As far as we know, no previous study has determined the relationship between volume and outcomes for shoulder arthroplasty. We hypothesized that surgeons and hospitals with higher caseloads of total shoulder arthroplasties and hemiarthroplasties have better outcomes as measured by decreased mortality rate, shorter length of stay in the hospital, reduced postoperative complications, and routine disposition of patients on discharge.Methods: Data on patients undergoing shoulder arthroplasty were extracted from the Nationwide Inpatient Sample databases for the years 1988 through 2000. Logistic regression with generalized estimating equations and multiple linear regression models were used to estimate the adjusted association between surgeon and hospital volume and outcomes for total shoulder arthroplasty and hemiarthroplasty after adjusting for comorbidity, age, race, household income, and sex.Results: The mortality rates for patients who had a total shoulder arthroplasty performed by surgeons who did fewer than two procedures per year (0.36%) or who did between two and fewer than four procedures per year (0.32%) were higher than those for patients who had a total shoulder arthroplasty performed by surgeons who did four procedures or more per year (0.20%). The risk-adjusted rate of postoperative complications after hemiarthroplasty was significantly higher for patients managed by surgeons who performed fewer than two procedures per year (1.68%) than for those managed by surgeons with a volume of five procedures or more per year (0.97%). The possibility of postoperative complications when total shoulder arthroplasty was performed in hospitals with a volume of fewer than five procedures (1.44%) or in those with a volume of five to ten procedures per year (1.45%) was significantly higher than that in hospitals where ten procedures or more were performed every year (0.64%). The mean lengths of stay in the hospital after total shoulder arthroplasty and hemiarthroplasty were significantly longer when the operations were performed by surgeons who did fewer than two procedures per year or when they were done in hospitals with a volume of fewer than five procedures per year or with a volume of five to fewer than ten procedures per year than when they were done in hospitals or by surgeons in the highest volume category (p < 0.001).Conclusions: Patients who have a total shoulder arthroplasty or hemiarthroplasty performed by a high-volume surgeon or in a high-volume hospital are more likely to have a better outcome.Level Of Evidence: Therapeutic study, Level III-2 (retrospective cohort study). See Instructions to Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

Paroxysmal hemicrania is a trigeminal autonomic cephalalgia first described in 1976, characterized by episodic attacks of excruciating unilateral periorbital and temporal stabbing, pulsatile, craw-like, or boring headaches lasting 2 - 30 minutes, accompanied by autonomic features, and alleviated by indomethacin. Paroxysmal hemicrania is divided into an episodic or chronic form, depending on the duration and frequency of the attacks. We describe a case of paroxysmal hemicrania in a patient with a contralateral anterior clinoid meningioma, which resolved after tumor resection. Most cases of autonomic cephalgias are primary headaches and not caused by underlying intracranial structural lesions. Based on our patient and a literature review of secondary causes of trigeminal autonomic cephalalgias, we recommend that all patients with trigeminal autonomic cephalalgias including paroxysmal hemicrania undergo neuroimaging studies. The preferred neuro-radiologic procedure should be a cranial MRI to exclude underlying structural intracranial lesions, particularly in the sellar and parasellar regions. [ABSTRACT FROM AUTHOR]

The hydrogen diffusion paths in undoped and doped α-Ti were studied by the projector augmented wave method within the density functional theory. Our calculations confirm that in the basal plane, the indirect mechanism of hydrogen diffusion between octahedral sites through a tetrahedral interstitial is more preferable than the direct path. The lowest energy barrier of 0.1 eV was found between the tetrahedral sites along the c axis; however, a hydrogen atom can only oscillate between them. The influence of substitutional impurities (transition- and simple-metal ones) on the main barriers is discussed. It was found that impurities of simple metals hamper the H mobility by increasing the activation energy, whereas most transition-metal solutes (3 d -metals of group 5–10) reduce the energy barriers. In general, a deeper understanding of the H diffusion behavior in doped α-Ti is achieved. The temperature-dependent diffusion coefficient and the activation energy for hydrogen atom hopping along the preferential path in pure titanium are found to be in agreement with the experimental data. [ABSTRACT FROM AUTHOR]

The hydrogen diffusion pathways were studied in B2-TiFe alloy within density functional theory (DFT) using the plane-wave pseudo-potential method. Our results confirm that the hydrogen diffusion between octahedral interstices where it is surrounded by two Fe and four Ti atoms along [10-1] direction is most preferential in TiFe bulk. The estimated hydrogen diffusion barrier of 0.62 eV differs insignificantly from values of barriers in pure Ti. The influence of substitutional transition and simple metal impurities on the energy barriers is discussed. It was found that impurities such as V, Cr, Mn decrease the hydrogen diffusion barriers along both considered pathways whereas Pd impurity decreases considerably the barrier along [00-1] direction that leads to the change of the diffusion mechanism. In general, the competition of structural and electronic factors strongly influences the hydrogen diffusion barriers. The present results provide a deep understanding of H behavior in TiFe bulk. [ABSTRACT FROM AUTHOR]

Abstract: We present a density functional theory (DFT) study of the hydrogen-metal interaction in the B2-TiFe alloy with Σ5(310) symmetrical tilt grain boundary (GB) and (310) free surface (FS). The influence of hydrogen on the electronic properties of alloy with GB and FS is analyzed for different hydrogen sorption sites. The hydrogen absorption/adsorption, binding and segregation energies are calculated at GB and FS. Our calculations reveal that H segregates more strongly to the surface than to the GB that results in decrease in the Griffith work, i.e., H makes the fracture of the GB easier. [Copyright &y& Elsevier]