A benchmark study on mantle convection in a 3-D spherical shell using CitcomS

As high-performance computing facilities and sophisticated modeling software become available, modeling mantle convection in a three-dimensional (3-D) spherical shell geometry with realistic physical parameters and processes becomes increasingly feasible. However, there is still a lack of comprehensive benchmark studies for 3-D spherical mantle convection. Here we present benchmark and test calculations using a finite element code CitcomS for 3-D spherical convection. Two classes of model calculations are presented: the Stokes' flow and thermal and thermochemical convection. For Stokes' flow, response functions of characteristic flow velocity, topography, and geoid at the surface and core-mantle boundary (CMB) at different spherical harmonic degrees are computed using CitcomS and are compared with those from analytic solutions using a propagator matrix method. For thermal and thermochemical convection, 24 cases are computed with different model parameters including Rayleigh number (7 × 10^3 or 10^5) and viscosity contrast due to temperature dependence (1 to 10^7). For each case, time-averaged quantities at the steady state are computed, including surface and CMB Nussult numbers, RMS velocity, averaged temperature, and maximum and minimum flow velocity, and temperature at the midmantle depth and their standard deviations. For thermochemical convection cases, in addition to outputs for thermal convection, we also quantified entrainment of an initially dense component of the convection and the relative errors in conserving its volume. For nine thermal convection cases that have small viscosity variations and where previously published results were available, we find that the CitcomS results are mostly consistent with these previously published with less than 1% relative differences in globally averaged quantities including Nussult numbers and RMS velocities. For other 15 cases with either strongly temperature-dependent viscosity or thermochemical convection, no previous calculations are available for comparison, but these 15 test calculations from CitcomS are useful for future code developments and comparisons. We also presented results for parallel efficiency for CitcomS, showing that the code achieves 57% efficiency with 3072 cores on Texas Advanced Computing Center's parallel supercomputer Ranger

Magnetic anisotropy in hole-doped superconducting Ba 0.67K 0.33Fe 2As2 probed by polarized inelastic neutron scattering

We use polarized inelastic neutron scattering (INS) to study spin excitations of optimally hole-doped superconductor Ba$_{0.67}$K$_{0.33}$Fe$_2$As$_{2}$ ($T_c=38$ K). In the normal state, the imaginary part of the dynamic susceptibility, $\chi^{\prime\prime}(Q,\omega)$, shows magnetic anisotropy for energies below $\sim$7 meV with c-axis polarized spin excitations larger than that of the in-plane component. Upon entering into the superconducting state, previous unpolarized INS experiments have shown that spin gaps at $\sim$5 and 0.75 meV open at wave vectors $Q=(0.5,0.5,0)$ and $(0.5,0.5,1)$, respectively, with a broad neutron spin resonance at $E_r=15$ meV. Our neutron polarization analysis reveals that the large difference in spin gaps is purely due to different spin gaps in the c-axis and in-plane polarized spin excitations, resulting resonance with different energy widths for the c-axis and in-plane spin excitations. The observation of spin anisotropy in both opitmally electron and hole-doped BaFe$_2$As$_2$ is due to their proximity to the AF ordered BaFe$_2$As$_2$ where spin anisotropy exists below $T_N$.Comment: 5 pages, 4 figure

Cross Cultural, Bilingual Group Experience: Evidence that Process-Focused Groups Work

A group of counselors, counselor educators and trainees convened a therapeutic group in Kajang, Malaysia, facilitated by a counselor from the United States. Although Malaysian counselors are accustomed to content-driven groups, this group adhered to process-focused protocols. A Delphi analysis on the outcome of the group was performed by a multinational team. Results suggested that the group followed the same stage development as described in the American literature and that the process-focused group appeared to facilitate the crossing of cultural lines more effectively than a content-driven group

Study On The Traffic Impact Of Logistic-Related Land Use

The North Butterworth Container Terminal (NBCT) and four intersections were selected in this study to address the traffic impact of logistic-related land use. The four intersections are NBCT Entrance Intersection (Intersection A), Jalan Heng Choon Thian/Jalan Bagan Luar/Jalan Kampung Gajah Intersection (Intersection B), Lebuhraya Butterworth Kulim/Jalan Siram/Jalan Sungai Nyior Intersection (Intersection C), and Lebuhraya Lingkaran Luar Butterworth/Jalan Chain Ferry/Jalan Perusahaan Intersection (Intersection D). Traffic data was collected at the entry of NBCT and four intersections near to the container terminal. The operation of NBCT is investigated by observation and interview conducted with the management team of Penang Port Sdn. Bhd. The results of analysis provide trip generation and peak hour of NBCT, and the variation in the traffic demand by vehicle types to and from the container terminal. From the data collected, the average process time of heavy lorries at the registration counter of NBCT is 104.8s. During the peak hour, there are 50 heavy lorries queued and waited on the NBCT approach road. The highest trip generated by NBCT is from 1615 hrs to 1715 hrs with the volume of 1697 pcu/hr. From NBCT, 73% of heavy lorries travelled to Intersection B by passing through Intersection A. As the heavy lorries reached Intersection B, 90% of the heavy lorries travelled to Intersection C. 51% of heavy lorries arrived at Intersection C travelled to Intersection D. From the analysis, it shows that high percentage of heavy lorries travelled along route from NBCT to Mak Mandin and Prai industrial area and vice versa. From the capacity analysis, the approach roads at each intersection with high volume of heavy lorries show LOS E and F

Vaccine-induced carbohydrate-specific memory B cells reactivate during rodent malaria infection

A long-standing challenge in malaria is the limited understanding of B cell immunity, previously hampered by lack of tools to phenotype rare antigen-specific cells. Our aim was to develop a method for identifying carbohydrate-specific B cells within lymphocyte populations and to determine whether a candidate vaccine generated functional memory B cells (MBCs) that reactivated upon challenge with Plasmodium (pRBCs). To this end, a new flow cytometric probe was validated and used to determine the kinetics of B cell activation against the candidate vaccine glycosylphosphatidylinositol conjugated to Keyhole Limpet Haemocyanin (GPI-KLH). Additionally, immunized C57BL/6 mice were rested (10 weeks) and challenged with pRBCs or GPI-KLH to assess memory B cell recall against foreign antigen. We found that GPI-specific B cells were detectable in GPI-KLH vaccinated mice, but not in Plasmodium-infected mice. Additionally, in previously vaccinated mice GPI-specific IgG1 MBCs were reactivated against both pRBCs and synthetic GPI-KLH, which resulted in increased serum levels of anti-GPI IgG in both challenge approaches. Collectively our findings contribute to the understanding of B cell immunity in malaria and have important clinical implications for inclusion of carbohydrate conjugates in malaria vaccines

Aphasia after Left Thalamic Infarction

We Examined a 70-Year-Old Woman Who Became Aphasic after a Left Thalamic Infarction. Computed Tomographic Scan Showed Injury that Was Largely Limited to the Ventral Anterior and Rostral Ventral Lateral Thalamic Nuclei. Speech Was Characterized by Reduced Voice Volume, Impaired Auditory and Reading Comprehension, Perseverations, Intermittent Use of Jargon, Fluctuations in the Ability to Perform Confrontation Naming, Extraneous Intrusions, Verbal Paraphasia, Intact Repetition Skills, and Fluent Speech that Was Laconic But Grammatically Correct. We Propose that the Deficits after Left Thalamic Injury Can Be Grouped into the Following Four Large Clusters: Extrapyramidal Deficits (Decreased or Fading Voice Volume), Deficits in Lexical Access (Anomia, Verbal Paraphasia), Deficits in Vigilance (Neologisms, Intrusions, Fluctuating Performance, Jargon, Perseverations), and Comprehension Defects. © 1984, American Medical Association. All Rights Reserved

Analysis of a Fragmenting Sunspot using Hinode Observations

We employ high resolution filtergrams and polarimetric measurements from Hinode to follow the evolution of a sunspot for eight days starting on June 28, 2007. The imaging data were corrected for intensity gradients, projection effects, and instrumental stray light prior to the analysis. The observations show the formation of a light bridge at one corner of the sunspot by a slow intrusion of neighbouring penumbral filaments. This divided the umbra into two individual umbral cores. During the light bridge formation, there was a steep increase in its intensity from 0.28 to 0.7 I_QS in nearly 4 hr, followed by a gradual increase to quiet Sun (QS) values in 13 hr. This increase in intensity was accompanied by a large reduction in the field strength from 1800 G to 300 G. The smaller umbral core gradually broke away from the parent sunspot nearly 2 days after the formation of the light bridge rendering the parent spot without a penumbra at the location of fragmentation. The penumbra in the fragment disappeared first within 34 hr, followed by the fragment whose area decayed exponentially with a time constant of 22 hr. The depleted penumbra in the parent sunspot regenerated when the inclination of the magnetic field at the penumbra-QS boundary became within 40 deg. from being completely horizontal and this occurred near the end of the fragment's lifetime. After the disappearance of the fragment, another light bridge formed in the parent which had similar properties as the fragmenting one, but did not divide the sunspot. The significant weakening in field strength in the light bridge along with the presence of granulation is suggestive of strong convection in the sunspot which might have triggered the expulsion and fragmentation of the smaller spot. Although the presence of QS photospheric conditions in sunspot umbrae could be a necessary condition for fragmentation, it is not a sufficient one.Comment: Accepted for publication in ApJ; 15 pages, 15 figures, 1 tabl