Robust Bottom-Up Gold Filling of Deep Trenches and Gratings.

This work extends an extreme variant of superconformal Au electrodeposition to deeper device architectures while exploring factors that constrain its function and the robustness of void-free processing. The unconventional bottom-up process is used to fill diffraction gratings with trenches 94 µm deep and 305 µm deep, with aspect ratios (height/width) of just below 20 and 15, respectively, in near-neutral 0.16 mol·L-1 Na3Au(SO3)2 + 0.64 mol·L-1 Na2SO3 electrolyte containing 50 µmol·L-1 Bi3+. Although the aspect ratios are modest compared to previously demonstrated void-free filling beyond AR = 60, the deepest trenches filled exceed those in previous work by 100 µm - a nearly 50 % increase in depth. Processes that substantially accelerate the start of bottom-up deposition demonstrate a linkage between transport and void-free filling. Final profiles are highly uniform across 65 mm square gratings because of self-passivation inherent in the process. Electron microscopy and electron backscatter diffraction confirm the fully dense Au and void-free filling suggested by the electrochemical measurements. X-ray transmission "fringe visibility" average more than 80 % at 50 kV X-ray tube voltage across the deeper gratings and 70 % at 40 kV across the shallower gratings, also consistent with uniformly dense, void-free fill across the gratings.

Accelerated Bottom-Up Gold Filling of Metallized Trenches.

This work extends previously detailed void-free, bottom-up feature filling in a near-neutral Na3Au(SO3)2 + Na2SO3 electrolyte containing micromolar concentrations of Bi3+. Bottom-up electrodeposition in 17 µm and 45 µm tall trenches with an aspect ratio greater than 10 is demonstrated using potentiostatic, stepped potential and/or stepped current control. Strategies to shorten the incubation period associated with slow deposition on uniformly passivated surfaces, which precedes bottom-up filling at fixed potential, are explored. The first electron backscatter diffraction studies of bottom-up filled Au deposits reveal large grains that span the trench width and often exceed tens of micrometers in length. In contrast, smaller grains are observed near the tops of filled trenches and, under conditions of marginal filling, mid-height within them.

Exploring the Limits of Bottom-Up Gold Filling to Fabricate Diffraction Gratings.

Gold deposition on rotating disk electrodes, Bi3+ adsorption on planar Au films and superconformal Au filling of trenches up to 45 µm deep are examined in Bi3+-containing Na3Au(SO3)2 electrolytes with pH between 9.5 and 11.5. Higher pH is found to increase the potential-dependent rate of Bi3+ adsorption on planar Au surfaces, shortening the incubation period that precedes active Au deposition on planar surfaces and bottom-up filling in patterned features. Decreased contact angles between the Au seeded sidewalls and bottom-up growth front also suggest improved wetting. The bottom-up filling dynamic in trenches is, however, lost at pH 11.5. The impact of Au concentration, 80 mmol/L versus 160 mmol/L Na3Au(SO3)2, on bottom-up filling is examined in trenches up to ≈ 210 µm deep with aspect ratio of depth/width ≈ 30. The microstructures of void-free, bottom-up filled trench arrays used as X-ray diffraction gratings are characterized by scanning electron microscopy (SEM) and Electron Backscatter Diffraction (EBSD), revealing marked spatial variation of the grain size and orientation within the filled features.

Evaluating the Incredible Years Toddler Parenting Programme with parents of toddlers in disadvantaged (Flying Start) areas of Wales.

BACKGROUND: Early risk factors for poor child outcomes are well established, and some group parenting programmes have demonstrated good outcomes for children under 3 years of age. This randomized controlled trial evaluated the effectiveness of the Incredible Years® Toddler Parenting Programme with parents of 1-year-old and 2-year-old children recruited by staff in disadvantaged Flying Start areas across Wales. METHODS: Eighty-nine families with a child aged between 12 and 36 months at baseline participated in a pragmatic community-based trial of the programme in eight Flying Start areas. Outcomes were measured at baseline, 6 months and 12 months using measures of parental mental health, competence, child behaviour, child development, home environment and blinded-observation of parent-child interactions. RESULTS: Significant intervention group improvements were found in parental mental well-being and observed praise at 6 months. Significant improvements for the intervention group at 12 months included child development, home environment and parental depression. CONCLUSION: The study provides preliminary evidence for programme attendance.

Central nervous system involvement in mantle cell lymphoma: clinical features, prognostic factors and outcomes from the European Mantle Cell Lymphoma Network.

BACKGROUND: Central nervous system (CNS) involvement in mantle cell lymphoma (MCL) is uncommon, and the manifestations and natural history are not well described. PATIENTS AND METHODS: We present the data on 57 patients with MCL who developed CNS involvement, from a database of 1396 consecutively treated patients at 14 institutions. RESULTS: The crude incidence of CNS involvement was 4.1%, with 0.9% having CNS involvement at diagnosis. Blastoid histology, B-symptoms, elevated lactate dehydrogenase, Eastern Cooperative Group performance status ≥2 and a high Mantle Cell Lymphoma International Prognostic Index score were enriched in the cohort with CNS involvement, and the presence of ≥1 of these features defined a high-risk subset (an actuarial risk of CNS involvement 15% at 5 years) in a single-institution subset. The median time to CNS relapse was 15.2 months, and the median survival from time of CNS diagnosis was 3.7 months. The white blood cell count at diagnosis <10.9 × 109/l, treatment of CNS involvement with high-dose anti-metabolites, consolidation with stem cell transplant and achievement of complete response were all associated with improved survival. CONCLUSIONS: In MCL, CNS involvement is uncommon, although some features may predict risk. Once manifest outlook is poor; however, some patients who receive intensive therapy survive longer than 12 months.

Rituximab Chimeric Anti-CD20 Monoclonal Antibody Therapy for Relapsed Indolent Lymphoma: Half of Patients Respond to a Four-Dose Treatment Program.

PURPOSE: The CD20 antigen is expressed on more than 90% of B-cell lymphomas. It is appealing for targeted therapy, because it does not shed or modulate. A chimeric monoclonal antibody more effectively mediates host effector functions and is itself less immunogenic than are murine antibodies. PATIENTS AND METHODS: This was a multiinstitutional trial of the chimeric anti-CD20 antibody, IDEC-C2B8. Patients with relapsed low grade or follicular lymphoma received an outpatient treatment course of IDEC-C2B8 375 mg/m2 intravenously weekly for four doses. RESULTS: From 31 centers, 166 patients were entered. Of this intent-to-treat group, 48% responded. With a median follow-up duration of 11.8 months, the projected median time to progression for responders is 13.0 months. Serum antibody levels were sustained longer after the fourth infusion than after the first, and were higher in responders and in patients with lower tumor burden. The majority of adverse events occurred during the first infusion and were grade 1 or 2; fever and chills were the most common events. Only 12% of patients had grade 3 and 3% grade 4 toxicities. A human antichimeric antibody was detected in only one patient. CONCLUSION: The response rate of 48% with IDEC-C2B8 is comparable to results with single-agent cytotoxic chemotherapy. Toxicity was mild. Attention needs to be paid to the rate of antibody infusion, with titration according to toxicity. Further investigation of this agent is warranted, including its use in conjunction with standard chemotherapy.

Interim Report on the Examination of Corrosion Damage in Homes Constructed With Imported Wallboard: Examination of Samples Received September 28, 2009.

Since many household systems are fabricated out of metallic materials, changes to the household environment that accelerate corrosion rates will increase the frequency of failures in these systems. Recently, it has been reported that homes constructed with imported wallboard have increased failure rates in appliances, air conditioner heat exchanger coils, and visible corrosion on electrical wiring and other metal components. At the request of the Consumer Product Safety Commission (CPSC), the National Institute of Standards and Technology (NIST) became involved through the Interagency Agreement CPSC-1-09-0023 to perform metallurgical analyses on samples and corrosion products removed from homes constructed using imported wallboard. This document reports on the analysis of the first group of samples received by NIST from CPSC. The samples received by NIST on September 28, 2009 consisted of copper tubing for supplying natural gas and two air conditioner heat exchanger coils. The examinations performed by NIST consisted of photography, metallurgical cross-sectioning, optical microscopy, scanning electron microscopy (SEM), and x-ray diffraction (XRD). Leak tests were also performed on the air conditioner heat exchanger coils. The objective of these examinations was to determine extent and nature of the corrosive attack, the chemical composition of the corrosion product, and the potential chemical reactions or environmental species responsible for accelerated corrosion. A thin black corrosion product was found on samples of the copper tubing. The XRD analysis of this layer indicated that this corrosion product was a copper sulfide phase and the diffraction peaks corresponded with those for the mineral digenite (Cu9S5). Corrosion products were also observed on other types of metals in the air conditioner coils where condensation would frequently wet the metals. The thickness of the corrosion product layer on a copper natural gas supply pipe with a wall thickness of 1.2 mm ± 0.2 mm was between 5 µm and 10 µm. These results indicate that a chemical compound that contains reduced sulfur, such as hydrogen sulfide (H2S), is present in the environment to which these samples were exposed. The literature indicates that these species strongly influence corrosion rates of most metals and alloys even at low concentrations. None of the samples examined were failed components, and no evidence of imminent failure was found on any of the samples examined. All of the corrosion damage observed to date is consistent with a general attack form of corrosion that will progress in a uniform and relatively predictable manner. No evidence of localized attack was found, but these forms of attack typically require an incubation period before they initiate. Therefore, the number of samples examined to date is too small to draw a conclusion on the relative probability of these forms of corrosion being able to cause or not cause failure. Samples from failed systems or from laboratory tests conducted over a wide range of metallurgical and environmental conditions will be required to assess the probability of these other forms of corrosion causing failure.

Extremes of glycemic control (HbA1c) increase hospitalization risk in diabetic hemodialysis patients in the USA.

BACKGROUND/AIMS: Because the relation between glycemic control and clinical outcomes found in the general diabetic population has not been established in diabetic hemodialysis patients, we evaluated the association between glycemic control and hospitalization risk. METHODS: We performed a primary retrospective data analysis on 23,829 hemodialysis patients with diabetes mellitus. Hemoglobin A(1c) at baseline and hospitalization events over the subsequent 12 months were analyzed and logistic regression models constructed for unadjusted, case mix-adjusted and case mix plus lab- adjusted data. Models were also constructed for cardiovascular, vascular access and sepsis hospitalizations. RESULTS: Eighty percent had type 2 DM, 5% type 1 and 14% not specified. The groups had similar mean HbA(1c) levels, 6.8 +/- 1.6%. Among all patients, the mean HbA(1c) values were >7% in 35%. The odds ratio of hospitalizations grouped by baseline HbA(1c) was significant at extremes of <5% and >11%. Similar relationships were evident for the subset of type 2 DM and in the analysis for hospitalizations due to sepsis. CONCLUSION: Extremely high and low HbA(1c) values are associated with hospitalization risk in diabetic hemodialysis patients. Prospective studies are needed to determine whether meeting recommended HbA(1c) targets might improve outcomes without posing additional risks in this population.

Electronic databases.

Electronic databases corresponding to most of the world's currently published literature and many other types of information are publicly available through online systems. Scientific databases that give references for publications are numerous and widely used; scientific numeric databases that are open to the public are far fewer and less used. Online retrieval systems are becoming easier to use as a result of the introduction of artificial intelligence techniques and user-friendly front ends and gateways. Issues related to electronic databases include public-private sector competition, transborder data flow, copyright, downloading, and the changing roles in database generation and processing.

Structure and functional expression of an omega-conotoxin-sensitive human N-type calcium channel.

N-type calcium channels are omega-conotoxin (omega-CgTx)-sensitive, voltage-dependent ion channels involved in the control of neurotransmitter release from neurons. Multiple subtypes of voltage-dependent calcium channel complexes exist, and it is the alpha 1 subunit of the complex that forms the pore through which calcium enters the cell. The primary structures of human neuronal calcium channel alpha 1B subunits were deduced by the characterization of overlapping complementary DNAs. Two forms (alpha 1B-1 and alpha 1B-2) were identified in human neuroblastoma (IMR32) cells and in the central nervous system, but not in skeletal muscle or aorta tissues. The alpha 1B-1 subunit directs the recombinant expression of N-type calcium channel activity when it is transiently co-expressed with human neuronal beta 2 and alpha 2b subunits in mammalian HEK293 cells. The recombinant channel was irreversibly blocked by omega-CgTx but was insensitive to dihydropyridines. The alpha 1B-1 alpha 2b beta 2-transfected cells displayed a single class of saturable, high-affinity (dissociation constant = 55 pM) omega-CgTx binding sites. Co-expression of the beta 2 subunit was necessary for N-type channel activity, whereas the alpha 2b subunit appeared to modulate the expression of the channel. The heterogeneity of alpha 1B subunits, along with the heterogeneity of alpha 2 and beta subunits, is consistent with multiple, biophysically distinct N-type calcium channels.

Sequence and expression of mRNAs encoding the alpha 1 and alpha 2 subunits of a DHP-sensitive calcium channel.

Complementary DNAs were isolated and used to deduce the primary structures of the alpha 1 and alpha 2 subunits of the dihydropyridine-sensitive, voltage-dependent calcium channel from rabbit skeletal muscle. The alpha 1 subunit, which contains putative binding sites for calcium antagonists, is a hydrophobic protein with a sequence that is consistent with multiple transmembrane domains and shows structural and sequence homology with other voltage-dependent ion channels. In contrast, the alpha 2 subunit is a hydrophilic protein without homology to other known protein sequences. Nucleic acid hybridization studies suggest that the alpha 1 and alpha 2 subunit mRNAs are expressed differentially in a tissue-specific manner and that there is a family of genes encoding additional calcium channel subtypes.

Primary structure of the gamma subunit of the DHP-sensitive calcium channel from skeletal muscle.

Affinity-purified, polyclonal antibodies to the gamma subunit of the dihydropyridine (DHP)-sensitive, voltage-dependent calcium channel have been used to isolate complementary DNAs to the rabbit skeletal muscle protein from an expression library. The deduced primary structure indicates that the gamma subunit is a 25,058-dalton protein that contains four transmembrane domains and two N-linked glycosylation sites, consistent with biochemical analyses showing that the gamma subunit is a glycosylated hydrophobic protein. Nucleic acid hybridization studies indicate that there is a 1200-nucleotide transcript in skeletal muscle but not in brain or heart. The gamma subunit may play a role in assembly, modulation, or the structure of the skeletal muscle calcium channel.

Solidification of Ni-Re Peritectic Alloys.

Differential thermal analysis (DTA) and microstructural and microprobe measurements of DTA and as-cast Ni-Re alloys with compositions between 0.20 and 0.44 mass fraction Re provide information to resolve differences in previously published Ni-Re phase diagrams. This investigation determines that the peritectic invariant between liquid, Re-rich hexagonal close packed and Ni-rich face center cubic phases, L + HCP → FCC, occurs at 1561.1 °C ± 3.4 °C (1σ) with compositions of liquid, FCC and HCP phases of 0.283 ± 0.036, 0.436 ± 0.026, and 0.828 ± 0.037 mass fraction Re, respectively. Analysis of the microsegregation in FCC alloys yields a partition coefficient for solidification, k = 1.54 ± 0.09 (mass frac./mass frac.). A small deviation from Scheil behavior due to dendrite tip kinetics is documented in as-cast samples. No evidence of an intermetallic phase is observed.

Structure and functional expression of alpha 1, alpha 2, and beta subunits of a novel human neuronal calcium channel subtype.

The primary structures of human neuronal alpha 1, alpha 2, and beta subunits of a voltage-dependent Ca2+ channel were deduced by characterizing cDNAs. The alpha 1 subunit (alpha 1D) directs the recombinant expression of a dihydropyridine-sensitive L-type Ca2+ channel when coexpressed with the beta (beta 2) and the alpha 2 (alpha 2b) subunits in Xenopus oocytes. The recombinant channel is also reversibly blocked by 10-15 microM omega-conotoxin. Expression of the alpha 1D subunit alone, or coexpression with the alpha 2b subunit, did not elicit functional Ca2+ channel activity. Thus, the beta 2 subunit appears to serve an obligatory function, whereas the alpha 2b subunit appears to play an accessory role that potentiates expression of the channel. The primary transcripts encoding the alpha 1D, alpha 2, and beta subunits are differentially processed. At least two forms of neuronal alpha 1D were identified. Different forms of alpha 2 and beta transcripts were also identified in CNS, skeletal muscle, and aorta tissues.

The Influence of Annealing Temperature and Time on the Formation of δ-Phase in Additively-Manufactured Inconel 625.

This research evaluated the kinetics of δ-phase growth in laser powder bed additively-manufactured (AM) Inconel 625 during post-build stress-relief heat treatments. The temperatures ranged between 650°C and 1050°C, and the times from 0.25 to 168 hours. The presence of δ-phase was verified for each temperature/time combination through multiple techniques. A conventional time-temperature-transformation diagram was constructed from the time-temperature data. Comparison to the growth in wrought IN625 with a similar nominal composition revealed that δ-phase formation occurred at least two orders of magnitude faster in the AM IN625. The results of this study also revealed that the segregated microstructure in the as-built condition has a strong influence on the kinetics of δ-phase formation in AM IN625 as compared to a homogenized material. Since control of the δ-phase growth is essential for reliable prediction of the performance of IN625 components in service, avoiding heat treatments that promote the formation of δ-phase in AM components that are not homogenized is highly recommended. This will be particularly true at elevated temperatures where the microstructural stability and the consistency of mechanical properties are more likely to be affected by the presence of δ-phase.

Sequential bcl-2 and c-myc oncogene rearrangements associated with the clinical transformation of non-Hodgkin's lymphoma.

We report a case of untreated non-Hodgkin's lymphoma with histologic progression over 1 yr from a low-grade, small cleaved follicular center cell lymphoma to a high-grade, small noncleaved follicular center cell lymphoma. Both lymphomas had identical immunoglobulin (Ig) heavy-chain joining gene (JH), kappa light-chain joining gene, and bcl-2 gene rearrangements, indicating the clonal identity of the two tumors. The Ig heavy chain locus on one chromosome 14 was involved in an initial t(14; 18) translocation as shown by comigrating JH and bcl-2 rearrangements. However, the oncogene c-myc was in the germline configuration in the initial lymphoma but had one allele rearranged near the 3' end of exon I in the high-grade tumor; DNA sequence analysis was consistent with a chromosomal breakpoint at that site. The presence of the c-myc rearrangement in the high-grade tumor suggest a role for c-myc in the clonal evolution of the low-grade tumor into a more aggressive lymphoma. The coexistence of both bcl-2 gene and c-myc oncogene rearrangements in the same tumor is unusual, with only a few cases reported. Furthermore, this case is unique in the direct demonstration of the histologic and clinical progression of a human lymphoma associated with the sequential rearrangement of the bcl-2 gene and the c-myc oncogene.

An approach for the identification of exemplar sites for scaling up targeted field observations of benthic biogeochemistry in heterogeneous environments.

Continental shelf sediments are globally important for biogeochemical activity. Quantification of shelf-scale stocks and fluxes of carbon and nutrients requires the extrapolation of observations made at limited points in space and time. The procedure for selecting exemplar sites to form the basis of this up-scaling is discussed in relation to a UK-funded research programme investigating biogeochemistry in shelf seas. A three-step selection process is proposed in which (1) a target area representative of UK shelf sediment heterogeneity is selected, (2) the target area is assessed for spatial heterogeneity in sediment and habitat type, bed and water column structure and hydrodynamic forcing, and (3) study sites are selected within this target area encompassing the range of spatial heterogeneity required to address key scientific questions regarding shelf scale biogeochemistry, and minimise confounding variables. This led to the selection of four sites within the Celtic Sea that are significantly different in terms of their sediment, bed structure, and macrofaunal, meiofaunal and microbial community structures and diversity, but have minimal variations in water depth, tidal and wave magnitudes and directions, temperature and salinity. They form the basis of a research cruise programme of observation, sampling and experimentation encompassing the spring bloom cycle. Typical variation in key biogeochemical, sediment, biological and hydrodynamic parameters over a pre to post bloom period are presented, with a discussion of anthropogenic influences in the region. This methodology ensures the best likelihood of site-specific work being useful for up-scaling activities, increasing our understanding of benthic biogeochemistry at the UK-shelf scale.

Nitrosourea-induced sister chromatid exchanges and correlation to cell survival in 9L rat brain tumor cells.

The ability of various nitrosoureas to induce sister chromatid exchanges (SCEs) in 9L rat brain tumor cells was investigated. Treatment of cells for 1 hr with the alkylating and cross-linking agents 1,3-bis(2-chloroethyl)-1-nitrosourea or chlorozotocin produced concentration-dependent increases in SCEs; elevations above controls were detected at concentrations of 1 microM or more. Above 0.25 mM, the alkylating agent ethylnitrosourea produced a dose-dependent increase in SCEs. Treatment with the carbamoylating agent 1,3-bis(trans-4-hydroxycyclohexyl)-1-nitrosourea did not induce SCEs. The maximum drug concentration at which SCEs are readily scored kills approximately 50% of cells. When accurate cell survival data in this dose range were obtained, a direct correlation between nitrosourea-induced cell kill, measured by a colony-forming efficiency assay, and SCE induction was found. Thus, analysis of the levels of SCE production may provide information about the efficacy of antineoplastic drugs.

Characterization of chromosome 11 translocation breakpoints at the bcl-1 and PRAD1 loci in centrocytic lymphoma.

The chromosome 11q13 bcl-1 locus is rearranged in the majority of centrocytic lymphomas, a CD5-positive B-cell non-Hodgkins lymphoma, as a result of reciprocal translocation with the 14q32 immunoglobulin heavy chain genes. Although several 11q13 bcl-1 breakpoint sites have been characterized, a postulated bcl-1 oncogene was not identified. Recently, however, a gene encoding cyclin D1, designated PRAD1, was proposed as a candidate bcl-1 oncogene; accumulated evidence now indicates this gene is bcl-1. To further characterize 11q13 breakpoints in B-cell neoplasms, we analyzed 26 centrocytic lymphomas and 68 other B-cell cancers by Southern blot using a panel of breakpoint probes spanning 110 kilobases of the bcl-1 and PRAD1 loci. Nineteen centrocytic cases (73%) showed rearrangement, 15 at bcl-1 breakpoint sites and 5 at PRAD1 sites. One case was rearranged at both bcl-1 and PRAD1 loci. All but the latter case showed comigration of rearranged bcl-1 or PRAD1 bands and immunoglobulin heavy chain joining gene bands, consistent with the t(11;14). bcl-1 rearrangement was present in only one of 68 noncentrocytic B-cell neoplasms; none showed PRAD1 rearrangement. Thus, bcl-1 and PRAD1 rearrangement is strongly associated with centrocytic lymphoma, providing a useful molecular marker for classifying this subtype of lymphoma and suggesting an important role for PRAD1 cyclin D1 in the pathogenesis of this neoplasm.