Erratum: Evidence for a Phase Transition in Silicate Melt at Extreme Pressure and Temperature Conditions [Phys. Rev. Lett. 108, 065701 (2012)].

This corrects the article DOI: 10.1103/PhysRevLett.108.065701.

Solid iron compressed up to 560 GPa.

Dynamic compression by multiple shocks is used to compress iron up to 560 GPa (5.6 Mbar), the highest solid-state pressure yet attained for iron in the laboratory. Extended x-ray absorption fine structure (EXAFS) spectroscopy offers simultaneous density, temperature, and local-structure measurements for the compressed iron. The data show that the close-packed structure of iron is stable up to 560 GPa, the temperature at peak compression is significantly higher than expected from pure compressive work, and the dynamic strength of iron is many times greater than the static strength based on lower pressure data. The results provide the first constraint on the melting line of iron above 400 GPa.

Performance of high-convergence, layered DT implosions with extended-duration pulses at the National Ignition Facility.

Radiation-driven, low-adiabat, cryogenic DT layered plastic capsule implosions were carried out on the National Ignition Facility (NIF) to study the sensitivity of performance to peak power and drive duration. An implosion with extended drive and at reduced peak power of 350 TW achieved the highest compression with fuel areal density of ~1.3±0.1 g/cm2, representing a significant step from previously measured ~1.0 g/cm2 toward a goal of 1.5 g/cm2. Future experiments will focus on understanding and mitigating hydrodynamic instabilities and mix, and improving symmetry required to reach the threshold for thermonuclear ignition on NIF.

Hot-spot mix in ignition-scale inertial confinement fusion targets.

Mixing of plastic ablator material, doped with Cu and Ge dopants, deep into the hot spot of ignition-scale inertial confinement fusion implosions by hydrodynamic instabilities is diagnosed with x-ray spectroscopy on the National Ignition Facility. The amount of hot-spot mix mass is determined from the absolute brightness of the emergent Cu and Ge K-shell emission. The Cu and Ge dopants placed at different radial locations in the plastic ablator show the ablation-front hydrodynamic instability is primarily responsible for hot-spot mix. Low neutron yields and hot-spot mix mass between 34(-13,+50) ng and 4000(-2970,+17 160) ng are observed.

Evidence for a phase transition in silicate melt at extreme pressure and temperature conditions.

Laser-driven shock compression experiments reveal the presence of a phase transition in MgSiO(3) over the pressure-temperature range 300-400 GPa and 10 000-16 000 K, with a positive Clapeyron slope and a volume change of ∼6.3 (±2.0) percent. The observations are most readily interpreted as an abrupt liquid-liquid transition in a silicate composition representative of terrestrial planetary mantles, implying potentially significant consequences for the thermal-chemical evolution of extrasolar planetary interiors. In addition, the present results extend the Hugoniot equation of state of MgSiO(3) single crystal and glass to 950 GPa.

Assembly of high-areal-density deuterium-tritium fuel from indirectly driven cryogenic implosions.

The National Ignition Facility has been used to compress deuterium-tritium to an average areal density of ~1.0±0.1 g cm(-2), which is 67% of the ignition requirement. These conditions were obtained using 192 laser beams with total energy of 1-1.6 MJ and peak power up to 420 TW to create a hohlraum drive with a shaped power profile, peaking at a soft x-ray radiation temperature of 275-300 eV. This pulse delivered a series of shocks that compressed a capsule containing cryogenic deuterium-tritium to a radius of 25-35 µm. Neutron images of the implosion were used to estimate a fuel density of 500-800 g cm(-3).

Velocity and timing of multiple spherically converging shock waves in liquid deuterium.

The fuel entropy and required drive energy for an inertial confinement fusion implosion are set by a sequence of shocks that must be precisely timed to achieve ignition. This Letter reports measurements of multiple spherical shock waves in liquid deuterium that facilitate timing inertial confinement fusion shocks to the required precision. These experiments produced the highest shock velocity observed in liquid deuterium (U(s) = 135 km/s at ∼2500 GPa) and also the first observation of convergence effects on the shock velocity. Simulations model the shock-timing results well when a nonlocal transport model is used in the coronal plasma.

Insulator-to-conducting transition in dense fluid helium.

By combining diamond-anvil-cell and laser-driven shock wave techniques, we produced dense He samples up to 1.5 g/cm(3) at temperatures reaching 60 kK. Optical measurements of reflectivity and temperature show that electronic conduction in He at these conditions is temperature-activated (semiconducting). A fit to the data suggests that the mobility gap closes with increasing density, and that hot dense He becomes metallic above approximately 1.9 g/cm(3). These data provide a benchmark to test models that describe He ionization at conditions found in astrophysical objects, such as cold white dwarf atmospheres.

Magnetic resonance imaging in dogs with neurologic impairment due to acute thoracic and lumbar intervertebral disk herniation.

BACKGROUND: Magnetic resonance imaging (MRI) is a correlate to physical examination in various myelopathies and a predictor of functional outcome. OBJECTIVES: To describe associations among MRI features, neurological dysfunction before MRI, and functional outcome in dogs with disk herniation. ANIMALS: One hundred and fifty-nine dogs with acute thoracolumbar disk herniation. METHODS: Retrospective case series. Signalment, initial neurological function as assessed by a modified Frankel score (MFS), and ambulatory outcome at hospital discharge and >3 months (long-term) follow-up were recorded from medical records and telephone interview of owners. Associations were estimated between these parameters and MRI signal and morphometric data. RESULTS: Dogs with intramedullary T2W hyperintensity had more severe pre-MRI MFS (median 2, range 0-4) and lower ambulatory proportion at long-term follow-up (0.76) than those dogs lacking hyperintensity (median MFS 3, range 0-5; ambulatory proportion, 0.93) (P=.001 and .013, respectively). Each unit of T2W length ratio was associated with a 1.9 times lower odds of long-term ambulation when adjusted for pre-MRI MFS (95% confidence interval 1.0-3.52, P=.05). Dogs with a compressive length ratio >1.31 (which was the median ratio within this population) had more severe pre-MRI MFS (median 3, range 0-5) compared with those with ratios < or =1.31 (median MFS 3, range 0-4; P=.006). CONCLUSIONS AND CLINICAL IMPORTANCE: MRI features were associated with initial injury severity in dogs with thoracolumbar disk herniation. Based on results of this study, the T2W length ratio and presence of T2W intramedullary hyperintensity appear to be predictive of long-term ambulatory status.

Streaked optical pyrometer system for laser-driven shock-wave experiments on OMEGA.

The temperature of laser-driven shock waves is of interest to inertial confinement fusion and high-energy-density physics. We report on a streaked optical pyrometer that measures the self-emission of laser-driven shocks simultaneously with a velocity interferometer system for any reflector (VISAR). Together these diagnostics are used to obtain the temporally and spatially resolved temperatures of approximately megabar shocks driven by the OMEGA laser. We provide a brief description of the diagnostic and how it is used with VISAR. Key spectral calibration results are discussed and important characteristics of the recording system are presented.

Pathologic diagnosis of breast cancer patients: evolution of the traditional clinical-pathologic paradigm toward "precision" cancer therapy.

We present an updated account of breast cancer treatment and of progress toward "precision" cancer therapy; we focus on new developments in diagnostic molecular pathology and breast cancer that have emerged during the past 2 years. Increasing awareness of new prognostic and predictive methodologies, and introduction of next generation sequencing has increased understanding of both tumor biology and clinical behavior, which offers the possibility of more appropriate therapeutic choices. It remains unclear which of these testing methodologies provides the most informative and cost-effective actionable results for predictive and prognostic pathology. It is likely, however, that an integrated "step-wise" approach that uses the traditional clinical-pathologic paradigms coordinated with molecular characterization of breast tumor tissue, will offer the most comprehensive and cost-effective options for individualized, "precision" therapy for patients with breast cancer.

Ghost fringe removal techniques using Lissajous data presentation.

A VISAR (Velocity Interferometer System for Any Reflector) is a Doppler velocity interferometer which is an important optical diagnostic in shockwave experiments at the national laboratories, used to measure equation of state (EOS) of materials under extreme conditions. Unwanted reflection of laser light from target windows can produce an additional component to the VISAR fringe record that can distort and obscure the true velocity signal. Accurately removing this so-called ghost artifact component is essential for achieving high accuracy EOS measurements, especially when the true light signal is only weakly reflected from the shock front. Independent of the choice of algorithm for processing the raw data into a complex fringe signal, we have found it beneficial to plot this signal as a Lissajous and seek the proper center of this path, even under time varying intensity which can shift the perceived center. The ghost contribution is then solved by a simple translation in the complex plane that recenters the Lissajous path. For continuous velocity histories, we find that plotting the fringe magnitude vs nonfringing intensity and optimizing linearity is an invaluable tool for determining accurate ghost offsets. For discontinuous velocity histories, we have developed graphically inspired methods which relate the results of two VISARs having different velocity per fringe proportionalities or assumptions of constant fringe magnitude to find the ghost offset. The technique can also remove window reflection artifacts in generic interferometers, such as in the metrology of surfaces.

K562 cell erythroid differentiation: requirement for a factor in fetal bovine serum.

K562 human erythroleukemia cells can be induced to make hemoglobin by a variety of inducing agents. Most of these agents are effective in media supplemented with fetal bovine serum (FBS), but not in media supplemented with newborn bovine serum (NBS). The active factor in FBS has an apparent molecular weight of 30,000 daltons and appears to be a protein on the basis of the following properties: lability at 100 degrees C, inactivation by desferrioxamine plus trypsin, resistance to periodate, and resistance to ribonuclease. Media containing NBS can be used for induction if supplemented by either this factor or transferrin of bovine or human origin. The small size of the active factor (mol. wt. approximately 30,000 daltons) indicates that it is not identical to bovine transferrin (mol. wt. approximately 77,000 daltons). However, when iron-saturated bovine transferrin is digested with trypsin, the peptide fragments produced resemble the FBS factor in activity, size, and reaction with antibovine serum transferrin.

Pathologic diagnosis, immunohistochemistry, multigene assays and breast cancer treatment: progress toward "precision" cancer therapy.

Clinical decisions regarding the suitability of adjuvant systemic therapy for individual patients with breast cancer depends on comprehensive assessment of the underlying biology of each patient's tumor. The previous clinical-pathologic paradigm for treatment, which had been used for decades, now has been augmented by significant advances in molecular analysis of breast tumor tissue samples. Molecular testing has the potential to understand better both tumor biology and clinical behavior, which enables more appropriate therapy choices to be made. We review the rapid evolution in profiling breast cancer tissues, and discuss the current evidence for clinical use of this information and how the emerging molecular paradigm can be integrated into the clinical-pathologic context as we progress toward "precision" therapy for patients with breast cancer and other solid tumors.

Analysis of type II and type X collagen synthesis in cultured growth plate chondrocytes by in situ hybridization: rapid induction of type X collagen in culture.

Type X collagen is produced by hypertrophic chondrocytes and serves as a highly specific marker for chondrocyte maturation. This study was designed to compare the expression of type II and type X collagen in growth plate sections and in distinct populations of chondrocytes in culture by in situ hybridization. Growth plate sections were treated with type II and type X collagen cDNA probes. Type II collagen mRNA was present throughout the growth plate but greatest in the lower proliferating and upper hypertrophic regions. In contrast, type X collagen was expressed only in the hypertrophic region. Northern analysis confirmed the specificity of the probe for type X collagen mRNA. Chick growth plate chondrocytes were separated by countercurrent centrifugal elutriation into five distinct populations and plated in serum-containing medium. These cultures were examined at varying times after plating for the expression of type II and type X collagen mRNA. At 3 h, type II collagen was present in the majority of the cells in all fractions, and approximately 15-20% of the cells expressed type X collagen mRNA. The cells expressing type X were from the hypertrophic region. At 24 h, however, nearly all cells in culture expressed type X mRNA, and there was a decrease in expression of type II collagen mRNA. Similar results were obtained in cultures in the absence of serum, and SDS-PAGE analysis of collagen synthesis confirmed the expression of type X collagen in all populations of fractionated cells at 24 h at the protein level. Type X collagen is an important marker through which cellular matruation can be evaluated in culture.(ABSTRACT TRUNCATED AT 250 WORDS)

Shared phenotypic expression of osteoblasts and chondrocytes in fracture callus.

Endochondral ossification in fracture healing of rats at 4, 8, 11, 14, and 21 days was analyzed using immunological and molecular probes for markers of the chondrocyte and osteoblast phenotype. These markers were osteocalcin, type I and type II collagen, including the probes homologous to the alternatively spliced forms of alpha 1 type II collagen, type IIA and type IIB. Histologic examination was performed on serial sections of the same tissue blocks to correlate cellular morphology with the immunohistochemical and in situ hybridization findings. At the junction of the cartilaginous and osseous tissue, an overlap of phenotype and morphology was noted. At the 8-day time point, the cells with chondrocyte morphology expressed intracellular message for osteocalcin and type I collagen. Immunohistochemical analysis of these cells also demonstrated intracellular osteocalcin. However, high levels of the type IIA collagen mRNA, which has previously been associated with less differentiated mesenchymal precursor cells, were expressed in both chondrocytes and osteoblasts. At the later time point (21 days) there was a substantial decrease in the number of cells displaying shared phenotypic characteristics. In situ hybridization and immunohistochemistry have permitted identification of an overlapping or shared phenotype in osteoblasts and chondroblasts in fracture callus. The findings raise important questions regarding the possible plasticity of mesenchymal cell phenotypes within the dynamic environment of fracture healing. Additional examination of these issues will further define factors involved in origin, differentiation, and maturation of bone and cartilage cells.

Regulation of osteoclastic activity in infection.

Figure 4 is a diagrammatic representation of five pathways involved in the activation of osteoclastic and osteoblastic cell activity during an infectious process. Pathways 1 and 2 are involved in the recruitment and activation of osteoclasts. These pathways are controlled by systemic hormones and cytokines of the infection/immune axis. As described above, many of the cytokines are synergistic and can evoke very strong stimuli for bone resorption; however, under normal conditions for any given number of bone-resorbing sites, there is always an equivalent compensatory stimulus to enhance bone formation. Pathways 3 to 5 govern the formation stimuli. Thus, for bone to be permanently lost there must be a disruption in the cellular communication that exists between pathways 1 and 2 and pathways 3 to 5. Such a disruption occurs in periodontal disease and osteomyelitis. At present, the molecular mechanisms that create the disruption in cell communication are not known. They may be complex and involve as yet unidentified cell biological principles, or they may be relatively simple reactions involving known factors and enzymes.

Hyperostosis cranii ex vacuo: a rare complication of shunting for hydrocephalus.

Hyperostosis cranii ex vacuo is a condition that may develop after successful ventricular shunting for hydrocephalus. It is characterized by diffuse thickening of the skull (particularly the inner table) involving the calvarium and the base. It is a diagnosis that distinguishes marked calvarial thickening from thickening of the skull because of other causes. It is an entity that needs to be considered in patients who have diffuse thickening of the skull, have premature closure of sutures, and who have been treated for hydrocephalus in the past.

Extraosseous primary and recurrent giant cell tumors: transforming growth factor-beta1 and -beta2 expression may explain metaplastic bone formation.

Giant cell tumor (GCT) of bone is a locally aggressive neoplasm with a high incidence of recurrence, usually at the site of previous osseous involvement. Primary and recurrent intraosseous lesions typically are lytic and do not show evidence of tumor-associated osteogenesis. Rarely, GCT recurs or is primary within soft tissue, and not infrequently, these extraosseous lesions show metaplastic bone formation that is visible radiographically. The authors report two recurrent and one primary case of extraosseous GCT, all of which exhibited significant deposits of metaplastic bone localized to the periphery of the lesions. In situ hybridization showed messenger RNA (mRNA) for transforming growth factor beta1 (TGF-beta1) and transforming growth factor beta2 (TGF-beta2) in neoplastic stromal cells and osteoclast-like giant cells within the recurrent and primary extraosseous tumors as well as in active osteoblasts on the surfaces of recently formed spicules of metaplastic bone. In situ hybridization also revealed mRNA for TGF-beta1 and TGF-beta2 in primary intraosseous tumors from these cases and from four cases in which neither extraosseous recurrence nor osseous metaplasia was identified. In the microenvironment of the extraosseous soft tissue, production of these osteoinductive growth factors by GCT may have a paracrine effect on mesenchymal progenitor cells, thereby stimulating the osteoblastic differentiation and metaplastic bone formation associated with these lesions.

Colon invasion by primary splenic lymphoma: a case report and review of the literature.

Primary splenic lymphoma accounts for 1% of lymphomas. The definition of primary splenic lymphoma is controversial and its clinical presentation is variable. This report describes a patient with primary non-Hodgkin's lymphoma of the spleen with transmural colonic invasion. This unique case represents the first reported instance of splenic lymphoma with histologically demonstrated invasion to the colonic mucosa. The clinical and pathologic features of this case and primary splenic lymphoma in general are reviewed.