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Spin-valley locking in monolayer transition metal dichalcogenides has attracted enormous interest, since it offers potential for valleytronic and optoelectronic applications. Such an exotic electronic state has sparsely been seen in bulk materials. Here, we report spin-valley locking in a Dirac semimetal BaMnSb2. This is revealed by comprehensive studies using first principles calculations, tight-binding and effective model analyses, angle-resolved photoemission spectroscopy measurements. Moreover, this material also exhibits a stacked quantum Hall effect (QHE). The spin-valley degeneracy extracted from the QHE is close to 2. This result, together with the Landau level spin splitting, further confirms the spin-valley locking picture. In the extreme quantum limit, we also observed a plateau in the z-axis resistance, suggestive of a two-dimensional chiral surface state present in the quantum Hall state. These findings establish BaMnSb2 as a rare platform for exploring coupled spin and valley physics in bulk single crystals and accessing 3D interacting topological states. Valley dependent spin polarization called spin-valley locking appears in absence of magnetism but it is limited to rare examples of transition metal dichalcogenides. Here, the authors report evidence of spin-valley locking and stacked quantum Hall effect in a bulk Dirac semimetal BaMnSb2. [ABSTRACT FROM AUTHOR]

The high performance of alloys is dependent on microstructure. And, alloying elements have significant influence on microstructure. In order to study the effect of Si and Mn elements on the microstructure and mechanical properties, different content of alloying elements, Si and Mn, are added into the matrix Al-4.5Cu alloy. The compounded alloys (CA) were prepared by vacuum suction casting. The microstructure of CA is investigated by a scanning electron microscope (SEM). And, the mechanical properties are tested by a universal testing machine and a microhardness tester. Analysis is conducted by comparing experimental results of CA with different content of Si and Mn. It was found that the irregular lamellar structure of the CA appeared with the increase of Si and Mn content. The solid solution was coexisted with the irregular lamellar laminated structure when both Si and Mn contents are 3 wt.%. The tensile strength of CA is the highest when the content of both Si and Mn is 1 wt%. Its ultimate tensile stress reaches 205.87 MPa, the elongation reaches 34.97% and the microhardness reaches 74.6 HV. When both Si and Mn contents are 2 wt.%, the tensile strength of CA is the weakest. Its ultimate tensile stress reaches 146.65 MPa, the elongation reaches 24.15% and the microhardness reaches 60.2 HV. The elongation of the CA decreases with an increase in Si and Mn contents. [ABSTRACT FROM AUTHOR]

Cross wedge rolling (CWR) is a forming technique wherein the processed material microstructure is controlled by the processing temperature. The initial results on CWR-processed T91 steels at different austenitizing temperatures are discussed with the microstructure analysis by various characterization techniques, such as the optical and scanning electron microscopies. The processed T91 specimens were much harder than water-quenched ones, their hardness being independent of the ausforming temperatures despite their microstructural differences. [ABSTRACT FROM AUTHOR]

Selected high-resolution seismic-reflection profiles and multibeam bathymetry acquired along the convergent Ecuador margin during the ATACAMES cruise on onboard the R/V L'Atalante (Jan.15-Feb.18, 2012) allow a preliminary evaluation of the neotectonic development and stratigraphic evolution of the margin based on the sismo-stratigraphic analysis of Quaternary sediment preserved on the margin shelf and upper slope. We present three major preliminary results. (1) The evolution of the Esmeraldas, Guayaquil and Santa Elena canyons. The head of the Esmeraldas canyon is the location of a continuous significant sediment transport. The Guayaquil canyon shows several episodes of deposition and incision. Aggrading sedimentation pattern in the canyon records several changes in relative sea-level. The subsidence of the Gulf of Guayaquil probably contributes to the good preservation of the canyon filling stages. The Santa Elena canyon is controlled by a SW-NE trending normal fault. (2) Variations of sediment accumulation and relative vertical motions are shown along-strike the shelf edge. Offshore the uplifted Manta peninsula, a pronounced subsidence of the shelf edge is documented by sedimentary clinoforms that have deposited in a morphological reentrant, and have migrated upslope testifying of a local subsidence meanwhile the adjacent La Plata Island area underwent uplift. In the Esmeraldas canyon area, a local uplift of the shelf is documented. (3) Two neotectonic fault systems with a possible transcurrent component are imaged across the shelf edge and upper margin slope offshore Jama, and Cape Galera. This possible transcurrent motion could be related to the reactivation of ancient faults of the upper plate by the subduction. These preliminary results indicate that the ATACAMES data set has a strong potential to evaluate the spatial and temporal contribution of tectonic and climate changes on the structural development and stratigraphic evolution of the Ecuador continental margin. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate care provided by primary care physicians in community practice to older patients presenting with cognitive impairment and dementia. Design: Secondary analysis of an intervention study. Setting: Primary care clinics. Participants: 101 patients 75 years and older enrolled in the ACOVE-2 study who presented with a new cognitive problem, new dementia, or prevalent dementia. Measurements: Patients assessment and management were evaluated from medical record review and caregiver interviews. Results: Among 34 patients presenting with a new cognitive problem, half received a cognitive assessment comprising of a test of memory and one other cognitive task, 41% were screened for depression and 29% were referred to a consultant. Of the 27 patients with newly diagnosed dementia, 15% received the components of a basic neurological examination, one-fifth received basic laboratory testing and for one third the medical record reflected an attempt to classify the type of dementia. Counseling was under-reported in the medical record compared to the caregiver interview for the 101 patients with dementia, but even the interview revealed that about half or fewer patients received counseling about safety and accident prevention, caregiver support or managing conflicts. Less than 10% were referred to a social worker. Conclusion: This small but detailed evaluation suggests patients presenting with cognitive problems to primary care physicians do not consistently receive basic diagnosis and management. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to evaluate the early clinical outcome of reconstruction with modular hemipelvic prostheses after pelvic sarcoma resection.Methods: We retrospectively reviewed eight patients between 2004 and 2007 who had periacetabular resections and reconstruction with a modular hemipelvic prosthetic system for pelvic sarcoma with a mean follow-up of 27 (range,10~54) months. Oncology outcome was assessed with survival rate, local recurrence rate, International Society of Limb Salvage (ISOLS) score and complications. Two patients had types I and II (periacetabular and ilium) pelvic resections, three had types II and III (periacetabular and pubis) pelvic resections and three had type I , II and III (ilium, periacetabular and pubis) pelvic resections. Nobody received chemotherapy or radiotherapy.Results: Five patients were free of disease; three patients died of disease. The overall survival rate was 62.5%. None had local recurrence, and 37.5% had metastasis. The mean ISOLS score was 19.5. No one had deep infection or dislocation.Conclusions: Reconstruction with a modular hemipelvic prosthetic system after periacetabular resection is a promising method because of the acceptable complication rate and satisfactory functional outcome. [ABSTRACT FROM AUTHOR]

The dissection of the genetic architecture of quantitative traits, including the number and locations of quantitative trait loci (QTL) and their main and epistatic effects, has been an important topic in current QTL mapping. We extend the Bayesian model selection framework for mapping multiple epistatic QTL affecting continuous traits to dynamic traits in experimental crosses. The extension inherits the efficiency of Bayesian model selection and the flexibility of the Legendre polynomial model fitting to the change in genetic and environmental effects with time. We illustrate the proposed method by simultaneously detecting the main and epistatic QTLs for the growth of leaf age in a doubled-haploid population of rice. The behavior and performance of the method are also shown by computer simulation experiments. The results show that our method can more quickly identify interacting QTLs for dynamic traits in the models with many numbers of genetic effects, enhancing our understanding of genetic architecture for dynamic traits. Our proposed method can be treated as a general form of mapping QTL for continuous quantitative traits, being easier to extend to multiple traits and to a single trait with repeat records. [ABSTRACT FROM AUTHOR]

Background: Allograft-prosthetic composite can be divided into three groups names cemented, uncemented, and partially cemented. Previous studies have mainly reported outcomes in cemented and partially cemented allograft-prosthetic composites, but have rarely focused on the uncemented allograft-prosthetic composites. The objectives of our study were to describe a surgical technique for using proximal femoral uncemented allograft-prosthetic composite and to present the radiographic and clinical results., Materials and Methods: Twelve patients who underwent uncemented allograft-prosthetic composite reconstruction of the proximal femur after bone tumor resection were retrospectively evaluated at an average followup of 24.0 months. Clinical records and radiographs were evaluated., Results: In our series, union occurred in all the patients (100%; range 5-9 months). Until the most recent followup, there were no cases with infection, nonunion of the greater trochanter, junctional bone resorption, dislocation, allergic reaction, wear of acetabulum socket, recurrence, and metastasis. But there were three periprosthetic fractures which were fixed using cerclage wire during surgery. Five cases had bone resorption in and around the greater trochanter. The average Musculoskeletal Tumor Society (MSTS) score and Harris hip score (HHS) were 26.2 points (range 24-29 points) and 80.6 points (range 66.2-92.7 points), respectively., Conclusions: These results showed that uncemented allograft-prosthetic composite could promote bone union through compression at the host-allograft junction and is a good choice for proximal femoral resection. Although this technology has its own merits, long term outcomes are yet not validated.