The interface between silicon and a high-k oxide

The ability to follow Moore's Law has been the basis of the tremendous success of the semiconductor industry in the past decades. To date, the greatest challenge for device scaling is the required replacement of silicon dioxide-based gate oxides by high-k oxides in transistors. Around 2010 high-k oxides are required to have an atomically defined interface with silicon without any interfacial SiO2 layer. The first clean interface between silicon and a high-K oxide has been demonstrated by McKee et al. Nevertheless, the interfacial structure is still under debate. Here we report on first-principles calculations of the formation of the interface between silicon and SrTiO3 and its atomic structure. Based on insights into how the chemical environment affects the interface, a way to engineer seemingly intangible electrical properties to meet technological requirements is outlined. The interface structure and its chemistry provide guidance for the selection process of other high-k gate oxides and for controlling their growth. Our study also shows that atomic control of the interfacial structure can dramatically improve the electronic properties of the interface. The interface presented here serves as a model for a variety of other interfaces between high-k oxides and silicon.Comment: 10 pages, 2 figures (one color

Lack of DMBT1 expression in oesophageal, gastric and colon cancers

Loss of sequences from human chromosome 10q has been reported in several different cancers. Recently, a second candidate tumour-suppressor gene, DMBT1, was identified in this chromosomal region. We studied the mRNA expression and homozygous deletion of this gene in human oesophageal, gastric and colon cancers. Reverse transcriptase polymerase chain reaction (RT-PCR) amplification demonstrated that 23 (53.5%) of 43 oesophageal, 5 (12.5%) of 40 gastric, and 4 (16.7%) of 24 colorectal cancer cases showed an apparent reduction in DMBT1 mRNA in tumour tissues compared with paired normal tissues. Twelve out of 15 oesophageal cancer cell lines also showed no expression. We next studied homozygous deletions within the DMBT1 gene in oesophageal cancers by using duplex PCR. Consequently, it was recognized in five (11.6%) of the primary tumours and two (13.3%) of the cell lines. These findings suggest that DMBT1 may act as a tumour-suppressor gene not only in brain tumours but also in gastrointestinal cancers, especially in oesophageal cancers. © 1999 Cancer Research Campaig

EML4–ALK fusion transcript is not found in gastrointestinal and breast cancers

Fusion genes have been identified as chromosomal rearrangements in certain cancers, such as leukaemia, lymphoma, and sarcoma. The EML4–ALK (EML4: echinoderm microtubule-associated-protein-like 4; ALK: anaplastic lymphoma kinase) fusion gene has been identified as an oncogene in non-small-cell lung cancer (NSCLC). This study examined the presence of this fusion transcript in gastrointestinal and breast cancers. We evaluated the expression of the EML4–ALK transcript in 104 lung cancer cases and in 645 gastrointestinal and breast cancer samples. Only one of the lung cancer samples tested positive for the EML4–ALK fusion transcript, whereas none were detected in 555 gastrointestinal and 90 breast cancer cases. Our data suggest that the EML4–ALK fusion transcript is not present in gastrointestinal or breast cancers and is specific to NSCLC

A Case of the Inferior Mesenteric Artery Arising from the Superior Mesenteric Artery in a Korean Woman

Anatomical variations of the inferior mesenteric artery are extremely uncommon, since the inferior mesenteric artery is regularly diverged at the level of the third lumbar vertebra. We found a rare case in which the inferior mesenteric artery arose from the superior mesenteric artery. The findings were made during a routine dissection of the cadaver of an 82-yr-old Korean woman. This is the tenth report on this anomaly, the second female and the first Korean. The superior mesenteric artery normally arising from abdominal aorta sent the inferior mesenteric artery as the second branch. The longitudinal anastomosis vessels between the superior mesenteric artery and inferior mesenteric artery survived to form the common mesenteric artery. This anatomical variation concerning the common mesenteric artery is of clinical importance, performing procedures containing the superior mesenteric artery

Development of a LAMP assay for detection of Leishmania infantum infection in dogs using conjunctival swab samples

Background: Leishmania infantum infections in dogs play a crucial role in the transmission of pathogens causing visceral leishmaniasis to humans in the Gansu province, northwest China. To be able to control zoonotic transmission of the parasite to humans, a non-invasive loop-mediated isothermal amplification (LAMP) assay to specifically detect L. infantum infections in dogs was developed. Methods: The primers used in the LAMP assay were designed to target kinetoplast DNA minicircle sequences of the L. infantum isolate MCAN/CN/90/SC and tested using DNA isolated from promastigotes of different Leishmania species. The LAMP assay was evaluated with conjunctional swab samples obtained from 111 and 33 dogs living in an endemic and a non-endemic region of zoonotic visceral leishmaniasis in the Gansu province, respectively. The LAMP assay was also compared with conventional PCR, ELISA and microscopy using conjunctional swab, serum and bone marrow samples from the dogs, respectively. Results: The LAMP assay detected 1 fg of L. infantum DNA purified from cultured promastigotes which was 10-fold more sensitive than a conventional PCR test using Leishmania genus-specific primers. No cross reaction was observed with DNA isolated from promastigotes of L. donovani, L. major, L. tropica, and L. braziliensis, and the L. infantum reference strain MHOM/TN/80/IPT1. The L. infantum-positive rates obtained for field-collected samples were 61.3%, 58.6%, 40.5% and 10.8% by LAMP, PCR, ELISA and microscopy, respectively. As only one out of the 33 samples from control dogs from the non-endemic region of zoonotic visceral leishmaniasis was positive by the LAMP assay and the PCR test, the observed true negative rate (specificity) was 97% for both methods. Conclusion: This study has shown that the non-invasive, conjunctional swab-based LAMP assay developed was more sensitive in the detection of leishmaniasis in dogs than PCR, ELISA and microscopy. The findings indicate that the LAMP assay is a sensitive and specific method for the field surveillance of domestic dogs, particularly of asymptomatic canines, in ZVL-endemic areas in western China

Is sea-ice-driven Eurasian cooling too weak in models?

This is the author accepted manuscript. The final version is available from Nature Research via the DOI in this recordData availability: The FACTS and CESM simulations are freely available and were obtained from the following repositories: https://www.esrl.noaa.gov/psd/repository/facts and https://www.cesm.ucar.edu/projects/community-projects/LENS

Entanglement entropy of Wilson surfaces from bubbling geometries in M-theory

We consider solutions of eleven-dimensional supergravity constructed in [1,2] that are half-BPS, locally asymptotic to $AdS_7\times S^4$ and are the holographic dual of heavy Wilson surfaces in the six-dimensional $(2,0)$ theory. Using these bubbling solutions we calculate the holographic entanglement entropy for a spherical entangling surface in the presence of a planar Wilson surface. In addition, we calculate the holographic stress tensor and, by evaluating the on-shell supergravity action, the expectation value of the Wilson surface operator.Comment: 42 pages, 4 figures, v2: minor modification

Nut production in Bertholletia excelsa across a logged forest mosaic: implications for multiple forest use

Although many examples of multiple-use forest management may be found in tropical smallholder systems, few studies provide empirical support for the integration of selective timber harvesting with non-timber forest product (NTFP) extraction. Brazil nut (Bertholletia excelsa, Lecythidaceae) is one of the world’s most economically-important NTFP species extracted almost entirely from natural forests across the Amazon Basin. An obligate out-crosser, Brazil nut flowers are pollinated by large-bodied bees, a process resulting in a hard round fruit that takes up to 14 months to mature. As many smallholders turn to the financial security provided by timber, Brazil nut fruits are increasingly being harvested in logged forests. We tested the influence of tree and stand-level covariates (distance to nearest cut stump and local logging intensity) on total nut production at the individual tree level in five recently logged Brazil nut concessions covering about 4000 ha of forest in Madre de Dios, Peru. Our field team accompanied Brazil nut harvesters during the traditional harvest period (January-April 2012 and January-April 2013) in order to collect data on fruit production. Three hundred and ninety-nine (approximately 80%) of the 499 trees included in this study were at least 100 m from the nearest cut stump, suggesting that concessionaires avoid logging near adult Brazil nut trees. Yet even for those trees on the edge of logging gaps, distance to nearest cut stump and local logging intensity did not have a statistically significant influence on Brazil nut production at the applied logging intensities (typically 1–2 timber trees removed per ha). In one concession where at least 4 trees ha-1 were removed, however, the logging intensity covariate resulted in a marginally significant (0.09) P value, highlighting a potential risk for a drop in nut production at higher intensities. While we do not suggest that logging activities should be completely avoided in Brazil nut rich forests, when a buffer zone cannot be observed, low logging intensities should be implemented. The sustainability of this integrated management system will ultimately depend on a complex series of socioeconomic and ecological interactions. Yet we submit that our study provides an important initial step in understanding the compatibility of timber harvesting with a high value NTFP, potentially allowing for diversification of forest use strategies in Amazonian Perù