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Exploring platinum (Pt)-solute nanoparticles (NPs) with multifaceted geometries, multifunctionality, and extended stability is key for several electrocatalytic applications. Here, we demonstrate that Pt-based alloy NPs modified with molybdenum (Mo) exhibit superior electrocatalytic properties compared with pure Pt NPs. Electrocatalytic testing of these Mo-modified Pt nanoalloys shows excellent catalytic performance in the hydrogen evolution reaction (HER), the oxygen reduction reaction (ORR), and the methanol oxidation reaction (MOR). We show that the catalytic functionalities in the ORR and the MOR achieved by the Mo-modified Pt nanoalloys are 15-25 times greater than the standard commercial Pt/C nanocatalyst. These nanoalloys also show enhanced resistance to poisoning by carbon monoxide (CO) adlayers and stability after accelerated durability tests (ADTs). We associate the origin of these exceptional electrocatalytic performances of the Pt-solute-Mo nanoalloys with their high degree of concavity, variations in vertex chemistry, and Pt enrichment along the corners and edges. Our findings offer a facile synthetic approach for the synthesis of Pt-solute nanoalloys as high-performance multifunctional electrocatalysts.

An empirical model is proposed for predicting layout dependent thickness variations in the semi-additive copper electrochemical plating (ECP) process. These variations are believed to be caused by the uneven depletion of copper sulfate during plating, causing low pattern density areas to plate faster than higher pattern density areas. Effective pattern density is extracted from the layout using a spatial filter and then mapped to the growth rates using a non-linear function. Test structures are designed that represent a wide range of feature sizes and pattern densities. After plating, these structures are profiled and used to fit the model, while other structures are used to validate its accuracy. Comparisons between the validation predictions and the experimental results show an average balanced root mean squared error (BRMSE) of 0.292 $\mu \text{m}$ , and a corresponding R2 value of 0.90. Fill patterns are then proposed and shown to control plating variations, by controlling pattern density. Finally, across-chip growth rate variations for a realistic interconnect layer are predicted, and experimentally confirmed.

Background The phase III CLinical Evaluation Of Pertuzumab And TRAstuzumab (CLEOPATRA) trial established the combination of pertuzumab, trastuzumab and docetaxel as standard first-line therapy for human epidermal growth factor receptor 2 (HER2)-positive locally recurrent/metastatic breast cancer (LR/mBC). The multicentre single-arm PERtUzumab global SafEty (PERUSE) study assessed the safety and efficacy of pertuzumab and trastuzumab combined with investigator-selected taxane in this setting. Patients and methods Eligible patients with inoperable HER2-positive LR/mBC and no prior systemic therapy for LR/mBC (except endocrine therapy) received docetaxel, paclitaxel or nab-paclitaxel with trastuzumab and pertuzumab until disease progression or unacceptable toxicity. The primary endpoint was safety. Secondary endpoints included progression-free survival (PFS) and overall survival (OS). Prespecified subgroup analyses included subgroups according to taxane, hormone receptor (HR) status and prior trastuzumab. Exploratory univariable analyses identified potential prognostic factors; those that remained significant in multivariable analysis were used to analyse PFS and OS in subgroups with all, some or none of these factors. Results Of 1436 treated patients, 588 (41%) initially received paclitaxel and 918 (64%) had HR-positive disease. The most common grade ≥3 adverse events were neutropenia (10%, mainly with docetaxel) and diarrhoea (8%). At the final analysis (median follow-up: 5.7 years), median PFS was 20.7 [95% confidence interval (CI) 18.9-23.1] months overall and was similar irrespective of HR status or taxane. Median OS was 65.3 (95% CI 60.9-70.9) months overall. OS was similar regardless of taxane backbone but was more favourable in patients with HR-positive than HR-negative LR/mBC. In exploratory analyses, trastuzumab-pretreated patients with visceral disease had the shortest median PFS (13.1 months) and OS (46.3 months). Conclusions Mature results from PERUSE show a safety and efficacy profile consistent with results from CLEOPATRA and median OS exceeding 5 years. Results suggest that paclitaxel is a valid alternative to docetaxel as backbone chemotherapy. Exploratory analyses suggest risk factors that could guide future trial design.

Nanoliposomal irinotecan (nal-IRI) is a liposomal formulation of irinotecan with a longer half-life (t1/2 ), higher plasma total irinotecan (tIRI), and lower SN-38 maximum concentration (Cmax ) compared with nonliposomal irinotecan. Population pharmacokinetic (PK) analysis of nal-IRI was performed for tIRI and total SN-38 (tSN38) using patient samples from six studies. PK-safety association was evaluated for neutropenia and diarrhea in 353 patients. PK-efficacy association was evaluated from a phase III study in pancreatic cancer NAPOLI1. Efficacy was associated with longer duration of unencapsulated SN-38 (uSN38) above a threshold and higher Cavg of tIRI, tSN38, and uSN38. Neutropenia was associated with uSN38 Cmax and diarrhea with tIRI Cmax . Baseline predictive factors were race, body surface area, and bilirubin. Analysis identified PK factors associated with efficacy, safety, and predictive baseline factors. The results support the benefit of nal-IRI dose of 70 mg/m2 (free-base; equivalent to 80 mg/m2 salt base) Q2W over 100 mg/m2 Q3W.

The 2015 ESC/ERS guidelines propose a risk assessment strategy for PAH patients. Several recent registry analyses support the association between risk profile and survival in PAH. The present post-hoc analysis assessed the prognostic and predictive value of risk assessment in the context of the GRIPHON study, hitherto the largest randomized clinical trial in PAH. GRIPHON randomized 1156 PAH patients (predominantly pre-treated) to selexipag, a prostacyclin receptor agonist, or placebo. Analyses were performed on the composite primary endpoint (morbidity/mortality events) by number of low-risk criteria (WHO functional class I-II; 6-min walk distance > 440 m; NT-proBNP

An empirical model is proposed for predicting layout-dependent thickness variations in the semi-additive copper electrochemical plating (ECP) process. These variations are believed to be caused by the uneven depletion of copper sulfate (CuSO 4 ) during plating, causing low pattern density areas to plate faster than higher pattern density areas. Effective pattern density is extracted from the layout using a spatial filter, and then mapped to the growth rates using a non-linear function. Test structures are designed that represent a wide range of feature sizes and densities. After plating, these structures are profiled and used to fit the model, while similar structures are used to validate its accuracy. Comparisons between the validation predictions and the experimental results show an average Balanced Root Mean Squared Error (BRMSE) of 0.292 µm, and a corresponding R2 value of 0.90.

Microalgae can be manipulated to accumulate certain cellular compounds of interest without the need for genetic modification - simply by controlling growth parameters such as nitrogen (N). Therefore, A. obliquus was batch-cultivated in a sleevebag photobioreactor system in N-deprived and N-rich medium to test the effect of N-status on CH4 yield under anaerobic digestion. Two different dewatering methods, i.e., centrifugation and sedimentation were applied to each resulting biomass. For the N-deprived biomass, cellular protein content dropped by 42–49%, and lipids increased up to 20% relative to the N-rich biomass. The highest CH4 yields were achieved with N-deprived, sedimented biomass (391 Nm3 t− 1 VS = normalized gas volume in m3 corrected to norm temperature and pressure per unit volatile solids), followed by N-rich sedimented biomass (361 Nm3 t− 1 VS). Centrifugation led to lower CH4 yields, where N-deprived biomass achieved 280 compared to 200 Nm3 t− 1 VS for N-rich microalgae. Our data indicate that valuable organic material was lost to the supernatant during the centrifugation step. We conclude that not only the N-status of cultivation, but also the biomass dewatering method has an instrumental effect on CH4 yield of microalgal biomass in anaerobic digestion. This work was performed in the frame of the Austrian COMET program under grant number 834018. It has received funding from the Republic of Austria and the Federal Provinces of Styria, Lower Austria and Burgenland. Co-funding from the industry partner Erber Group shall be highly acknowledged.

Moving granular bed filters (MGBFs) are the promising approach to improve the quality of pyrolysis oil by removing char particles from fast pyrolysis vapor streams. To minimize the commercial MGBF system, the inner MGBF structures were modified, resulting in differential granular media velocities between inlet and outlet gas stream. The modified structure was applied to increase the removal efficiency under the same superficial gas velocity. The experiments were conducted at room temperature and the designed parameters included the insert length and angle of inserted plates in the bottom of MGBF. In this study, the insert plates were used to distinguish the MGBF into two particle flow streams in the same section. The section area was the function of particle response angle, insert length, insert angle, and angle of the MGBF boundary plate. An accurate equation for determining the mass flow rate of the bed material particle and section area was proposed in this study. In addition, cold model filter tests were conducted on differential designs for three sets of flow fields. These results show that differential flow field designs can effectively enhance filtration efficiency. Under the same filtration pressure decline or loss, the filtration efficiency can be increased from the baseline of 95.4% to 99.9%.

Waste liquids with low-calorific values are not easy to burn. In this experiment, a furnace with a pair of burners for high-cycled alternate firing was utilized to burn the low-calorific value liquids. In a 1383 K furnace, 1173 K preheated air was achieved via these burners equipped with regenerators. It was observed that the alternate firing with highly preheated air was an effective way to ignite and burn the low-calorific value liquids. The preheated air temperature was higher than the auto-ignition temperature of the flammable mixture of the waste liquids. The combustion gas temperature in the furnace was quite uniform via the high-cycled alternate firing, resulting in a longer residence time of combustion in the furnace as compared to the conventional incinerator. The convective heat transfer in this furnace was higher than that of the conventional incinerator, and more useful energy was extracted from the waste liquids for end users. For the waste liquids with lower heating values of 15.0 MJ/kg (19 wt.% water) and 10.4 MJ/kg (42 wt.% water), it was found that 49% and 10% of the heating values of the waste liquids, respectively, could be used for utility energy. Furthermore, the waste liquid with a lower heating value of 7.1 MJ/kg (45 wt.% water) could burn itself in this furnace without the need of co-firing of any auxiliary fuels. NOx and CO emissions were lower than 60 ppmv (6% O2) and 50 ppmv (6% O2), respectively, for all tests.

Plants that can take up amino acids directly from the soil solution may have a competitive advantage in ecosystems where inorganic nitrogen sources are scarce. We hypothesized that diverse mosses in cold, N-stressed ecosystems share this ability. We experimentally tested 11 sub-arctic Swedish moss species of wide-ranging taxa and growth form for their ability to take up double labelled (15N and 13C) glycine and aspartic acid in a laboratory setup as well as in a realistic field setting. All species were able to take up amino acids injected into the soil solution to some extent, although field uptake was marginal to absent for the endohydric Polytrichum commune. The 11 moss species on average took up 36 ± 5% of the injected glycine and 18 ± 2% of the aspartic acid in the lab experiment. Field uptake of both glycine (24 ± 5%) and aspartic acid (10 ± 2%) was lower than in the lab. Overall differences in uptake amongst species appeared to be positively associated with habitat wetness and/or turf density among different Sphagnum species and among non-Sphagnum species, respectively. Species from habitats of lower inorganic N availability, as indicated tentatively by lower tissue N concentrations, showed relatively strong amino acid uptake, but this was only significant for the field uptake among non-Sphagnum mosses. Further experiments are needed to test for consistent differences in amino acid uptake capacity among species and functional groups as determined by their functional traits, and to test how the affinity of cold-biome mosses for amino acids compares to that for ammonium or nitrate. Still, our results support the view that widespread moss species in cold, N-stressed ecosystems may derive a significant proportion of their nitrogen demand from free amino acids. This might give them a competitive advantage over plants that depend strongly on inorganic N sources.

A Nafion ® /ruthenium-oxide pyrochlore chemically modified electrode (CME) was used for the determination of serotonin in human blood by square-wave voltammetry. Compared to a bare glassy carbon electrode, the chemically modified electrode exhibits a marked enhancement of the current response. With 45 s preconcentration time at a potential of −0.3 V vs. Ag/AgCl, linear calibration curves are obtained in pH 9 ammonia buffer over 0.01–0.5 μM and 2–20 μM with a detection limit (3 σ ) of 2 nm. The chemically modified electrode was applied for the measurement of serotonin in human blood.

Parylene-F, poly(tetrafluoro-para-xylylene) (PA-F), has potential applications in microelectronics because of its high thermal stability and low dielectric constant. We found that a new precursor, 1,4-bis(trifluoromethyl) benzene (TFB) with a trace presence of α,α′-dibromo-α,α,α′,α′-tetrafluoro-p-xylene (DBX), can be used to produce PA-F films. PA-F films from this precursor are produced using a reaction line and a conventional deposition system. This process is simpler than previously reported processes and produces PA-F films with less impurities. The dielectric constant of the PA-F films produced by this process is 2.25 ± 0.05 at 1 MHz. The deposition process and the material properties of the PA-F films produced are presented.

A Nafion/ruthenium oxide pyrochlore chemically modified electrode (CME) was used for the selective determination of dopamine (DA) in the presence of a high concentration of ascorbic acid by square-wave voltammetry. Compared to a bare glassy carbon electrode, the CME exhibits an apparent shift of the oxidation potentials in cathodic direction and a marked enhancement of the current response. The selective sensing of DA is achieved by combining the electrocatalytic function of the ruthenium oxide pyrochlore catalyst with the charge-exclusion and preconcentration features of Nation. With a preconcentration time of 60 s at a potential of −0.3 V (vs. Ag/AgCl), linear calibration plots are obtained for dopamine in 0.1 M, phosphate buffer (pH 7.4) over 0–20 μM with a detection limit (3σ) of 0.1 μM.

Structural characteristics of poly(tetrafluoroparaxylylene) (PA‐F) films deposited directly from C6H4(CF2Br)2 precursor have been studied using Fourier transform infrared spectroscopy (FTIR) and x‐ray photoelectron spectroscopy (XPS). Zn was used as the catalyst and the vapor pyrolysis of precursor was carried out between 350 and 400 °C. It is shown that the FTIR and XPS spectra of the PA‐F films deposited from the precursor are comparable to those made from the conventional dimer route. Dissociation of the PA‐F films does not occur up to an annealing temperature of 500 °C. Both Zn and Br contaminants were observed in the XPS spectra. However, we found that the Br contamination disappears after annealing to an elevated temperature (≥350 °C), while Zn impurities still remain in the film.

Room-temperature rate constants for the reactions of three hydrazine fuels with O( 3 P) were measured. A laser photolysis-resonance fluorescence technique was used in the experiments. The reactions were monitored by the decay of 131 nm, O( 3 S- 3 P) resonance fluorescence under both high-pressure (∼50 Torr) and low-pressure (1-3 Torr) conditions

With materials innovation driving recent logic and memory scaling in the semiconductor industry, High-Productivity Combinatorial™ (HPC) technology can be a powerful tool for finding optimum materials solutions in a cost-effective and efficient manner. This paper will review unique HPC wet processing, physical vapor deposition (PVD), and atomic layer deposition (ALD) capabilities that were developed, enabling site-isolated testing of multiple conditions on a single 300mm wafer. These capabilities were utilized for exploration of new chalcogenide alloys for phase change memory, and for metal gate and high-K dielectric development for high-performance logic. Using an HPC PVD chamber, a workflow was developed in which up to 40 different precisely controlled GeSbTe alloy compositions can be deposited in discrete site-isolated areas on a single 300mm wafer and tested for electrical & material properties, using a custom in-situ high-throughput sheet-resistance measurement setup, to get very accurate measurements of the amorphous – crystalline transition temperature. We will review how resistivity as a function of temperature, crystallization temperature, final and intermediate (if any) crystalline phases were mapped for a section of the GeSbTe phase diagram, using only a few wafers. Another area where HPC can be very valuable is for finding optimum materials for high-k dielectrics and metal gates for high-performance logic transistors. Assessing the effective work-function (EWF) for a given high-k dielectric metal-gate stack for PFET and NFET transistors is a critical step for selecting the right materials before further integration. One way to obtain EWF is by using a terraced oxide wafer with different SiO2 thickness bands underneath the high-k dielectric. We report a HPC workflow using our wet, ALD & PVD capabilities, to quickly assess EWF for multiple different high-k dielectrics and metal gate stacks. This workflow starts with a HPC wet etch of thermal silicon oxide, creating different oxide thicknesses 1–10nm in select areas of the same substrate. This is followed by atomic layer deposition of a high-k dielectric film such as HfO2. Next, a metal e.g., TaN is deposited through a physical mask or patterned post-deposition to complete the formation of MOS capacitors. The final step is C-V measurements and C-V modeling to extract Vfb, high-k dielectric constant, EOT, and EWF from Vfb vs EOT plot. This workflow was used to extract EWF for a TaN metal gate with an ALD HfO2 high-k dielectric using a metal-organic precursor. We will discuss how EWF for this system was affected by annealing post-dielectric deposition & post-metallization, different annealing temperatures & ambients, Hf pre-cursors and interfacial cap layers e.g., La2O3 & Al2O3. Finally, we will also discuss more advanced versions of this workflow where the ALD high-k dielectric and PVD metal gate is also varied on the same wafer using HPC versions of ALD & PVD chambers.

Spectra of the ν3 vibrational mode of OCS (around 2000 cm−1 ) isolated in solid Ar, Xe, and N2 at cryogenic temperatures and high dilution (1:50 000 typically) have been measured with an interferometric spectrometer at high resolution (0.01 cm−1 ). The spectra have in common a sharp feature (for any one isotopic form) to the red of a much broader feature. They differ in the way these features move and change width with changes in matrix temperature. The environment of the solute, which is deduced in detail in a companion paper, can be assigned to these features, implying that precision line shape measurements can be used to probe the immediate environment of a highly dilute solute. Applications of this technique to the study of photodissociation in cryogenic solids and to the study of diffusion are discussed.

Two-step laser photodissociation of gas phase OCS over the temperature range 296–150 K was used to enrich oxygen and sulfur isotopes. The 0–2v2 vibrational transition of OCS was pumped with a line-tuned CO2 TEA laser, followed by UV photodissociation with a KrF laser at 249 nm. The degree of isotope enrichment achieved in the photodissociation products was found to increase significantly with decreasing sample temperature, reaching a maximum enrichment factor 4.84±0.5 at 150 K for enrichment of 18O. The observed temperature dependence was fit to a simple theory based on the effect of the thermal population of excited vibrational levels on the photodissociation cross-section. The dependence of isotope enrichment on the densities of OCS, xenon diluent gas and C2D4 scavenger, was also investigated.

SummaryIncreased plasma levels of plasminogen activator inhibitor-1 (PAI-1) have been shown to exist in 40 to 60% of patients with stable coronary artery disease and have been suggested to be responsible for the development of coronary thrombotic complications. However, it is also discussed whether PAI-1 elevation might mainly be due to variables like increased age or to reactive mechanisms caused e.g. by the chest pain itself. To exclude age dependent ui pain related influences, age-matched patients with stable angina pectoris (NHYA II) and angiographically proven coronary artery disease (CAD, n = 16) or without evidence for coronary sclerosis (variant angina, n = 10; angina-like syndrome with normal coronary angiogram, n = 5; non-CAD, n = 15) have been investigated for their plasma PAI-1 activity and t-PA antigen levels. The mean PAI activity in CAD patients (17.5 U/ml) was significantly higher than in non-CAD patients (9.6 U/ml) (p

In Saccharomyces cerevisiae, HOT1-stimulated recombination has been implicated in maintaining homology between repeated ribosomal RNA genes. The ability of HOT1 to stimulate genetic exchange requires RNA polymerase I transcription across the recombining sequences. The trans-acting nuclear mutation hrm3-1 specifically reduces HOT1-dependent recombination and prevents cell growth at 37 degrees . The HRM3 gene is identical to DEG1. Excisive, but not gene replacement, recombination is reduced in HOT1-adjacent sequences in deg1Delta mutants. Excisive recombination within the genomic rDNA repeats is also decreased. The hypo-recombination and temperature-sensitive phenotypes of deg1Delta mutants are recessive. Deletion of DEG1 did not affect the rate of transcription from HOT1 or rDNA suggesting that while transcription is necessary it is not sufficient for HOT1 activity. Pseudouridine synthase 3 (Pus3p), the DEG1 gene product, modifies the anticodon arm of transfer RNA at positions 38 and 39 by catalyzing the conversion of uridine to pseudouridine. Cells deficient in pseudouridine synthases encoded by PUS1, PUS2 or PUS4 displayed no recombination defects, indicating that Pus3p plays a specific role in HOT1 activity. Pus3p is unique in its ability to modulate frameshifting and readthrough events during translation, and this aspect of its activity may be responsible for HOT1 recombination phenotypes observed in deg1 mutants.

Contains fulltext : 57187.pdf (Publisher’s version ) (Closed access) The present study was carried out on the evaluation and application of new biomarkers for populations exposed to occupational diesel exhaust at oil shale mines. Since not only genotoxic effects may play an important role in the generation of tumors, the level of porphyrin metabolism was proposed as a biomarker of diesel exhaust exposure effects. The data on determination of 5-aminolevulinic acid (ALA) synthesis and heme formation in lymphocytes from groups of 50 miners exposed to diesel exhaust and 50 unexposed surface workers of oil shale mine are presented. All workers were examined and interviewed using structured questionnaires. The levels of benzene, carbon monoxide and nitric oxides in air as well as concentrations of 1-nitropyrene and elemental carbon in particulate matter were used for evaluation of exposure to diesel exhaust in mine. The levels of ALA and protoporphyrin (PP), activities of ALA synthetase (ALA-S) and ferrochelatase (FC), as well as levels of PP associated with DNA (PP/DNA) were investigated in lymphocytes spectrophotometrically. Significant differences in activity of ALA synthesis and heme formation between exposed miners and surface workers were found (207+/-23 vs. 166+/-14 pmol/10(6) lymp./30' for ALA-S and 46.1+/-3.8 vs. 54.8+/-4.1 pmol/10(6) lymp./60' for FC activities, respectively, P

Classic pulmonary thromboembolism research has documented that large pulmonary thromboemboli lyse spontaneously, suggesting potent fibrinolytic activity in human pulmonary artery (Pa). This concept conflicts with published animal studies in which the proximal Pa was reported to be devoid of tissue plasminogen activator (t-PA) expression. The current study used in situ hybridization protocols to demonstrate t-PA expression in samples of human main Pa (n = 30). Real-time PCR was used to demonstrate quantitatively that the levels of t-PA transcripts were higher than those of its primary regulator [ie, plasminogen activator-inhibitor 1 (PAI-1)] in the Pa samples. Immunologic and functional assays extended these observations by demonstrating that levels of t-PA antigen were higher than PAI-1 antigen, which resulted in the detection of free t-PA activity. This contrasted with the fibrinolytic balance of matched samples of aorta (n = 6) in which PAI-1 transcripts and antigen values were higher than the corresponding t-PA values, and only M(r) 110 kDa t-PA-PAI-1 complexes could be detected in functional assays. To assess the relative fibrinolytic contribution of the endothelial cell layer, Pa endothelial cells and aortic endothelial cells were scraped and propagated in culture for 20 +/- 6 days. Pa endothelial cell-conditioned media revealed increased t-PA/PAI-1 antigen ratios. Taken together, our data indicate that the balance between t-PA and PAI-1 is shifted in human main Pa to favor net PA activity.

Laboratory studies were conducted to determine the rates at which perchlorate is released from perchlorate-containing solid propellants and the influence of temperature and salinity on the rates. Perchlorate release rates from carboxyl-terminated polybutadiene (CTPB), hydroxyl-terminated polybutadiene (HTPB), polybutadiene-acrylic acid-acrylo-nitrile terpolymer (PBAN), and polyurethane (PU) solid propellants were determined and are reported as diffusion coefficients. The diffusion coefficients for all propellant types and conditions tested were in the range of 3.6 x 10(exp -12) to 1.1 X 10(exp -13) sq m/s. Modeling studies of solid-propellant debris impacts for Delta IV and Atlas V cases were also conducted using an improved methodology based on the ACTA debris model.

Umbelliferone, naringenin 4′,7-dimethyl ether, matairesinol, pinoresinol, sitosterol, campesterol and seven diterpenes were isolated from the leaves of armand pine. The diterpenes are carboxylic acids and methyl esters of the labdane- and abietane types including lambertianic acid, pinusolide, 16-hydroxylabda-8(17),13-diene-15,19-dioic acid butenolide, isocupressic acid, 15-hydroxydehydroabietic acid, 15-nor-16-hydroxy-14-oxolabd-8(17)-enoic acid and 7,8-dihydro-8,15-dihydroxyabietic acid. Among them, the latter two compounds are newly found in nature.

Abstract —Information is lacking on the mechanisms involved in the organization, resolution, and repair of the vascular lumen after acute pulmonary thromboembolism. Because recent data suggest that the balance between plasminogen activators (PAs) and type 1 plasminogen activator inhibitor (PAI-1) plays a role in regulating cell migration within the extracellular matrix, we investigated the expression of these molecules by immunohistochemical and in situ hybridization analysis of pulmonary artery specimens from patients suffering fatal pulmonary embolism. The data were compared with the expression of these molecules in both patients’ noninvolved pulmonary arteries and organ donor pulmonary arteries. Regions of initial organization and vascular remodeling were identified by a modified trichrome stain and by the presence of proliferating cell nuclear antigen (PCNA), a cell marker of proliferation. Staining for tissue-type PA antigen was low to undetectable in endothelial cells directly in contact with the fibrin-platelet thromboembolus and in areas in which the endothelial cell lining was replaced by cell growth into the thrombus. Urokinase-like PA (u-PA) expression was detected in mononuclear cells within the thrombus in the initial phase of thromboembolism and within cells migrating into the thrombus during the later stages of organization. PAI-1 expression was elevated in the monolayer of endothelial cells underlying the fresh platelet-fibrin thromboembolus and in a PCNA-positive cell population present between the pulmonary arterial intima and the thromboembolus that represents early organization. Increased expression of PAI-1 may play a role in inhibiting proteolysis and fostering the localization of the acute fibrin-platelet thrombus to the vascular wall, which is followed by the upregulation of u-PA in migrating cells during the reorganization process.

Several novel processes have been developed in our lab to synthesize and deposit polymers that have extremely low dielectric constants (below 2.5) as thin films. These reactive intermediates are condensed onto wafers in a vacuum chamber and no chemical waste is produced. Furthermore, cold traps can be used to recover uncondensed monomers through the pumping system. Because of the extremely low dielectric constant, very low moisture uptake and high temperature stability of these vapor depositable materials, these environmentally friendly polymers are very attractive for future electronic applications as interlayer dielectrics. Examples are Parylene-F(fluorinated), poly(naphthalene) (PNT-N), poly(fluorinated naphthalene) (PNT-F), and Teflon AF 1600 (amorphous). These films were deposited at substrate temperatures between −20 and 350 °C and at deposition pressure was 10−4−2.5 Torr. The film thicknesses were between 0.1–10 μ. and dielectric constants were between 1.9–2.5. The thermal stabilities of these films were between 360–590 °C. Among them, poly(fluorinated naphthalene) dissociates at about 590 °C. Poly(naphthalene) and poly(fluorinated naphthalene) are obtained as films by vaporizing monomers in vacuo and transporting the vapor to a hot surface.

Parylene films, depending on the type, are thermally stable up to 530°C and have low dielectric constants ranging from 2.35 to 3.15. One of the most interesting properties of this material is its vapor depositability. Conventional vapor deposition involves cracking the parylene dimers at temperatures from 600 to 730 °C and polymerizingthe monomers at - 35 °C to RT. We have developed a simpler and less expensive technique that directly uses the precursors from which the dimers are made. This method requires the use of metal catalysts to produce parylene films. We have used the precursors α,α'-dibromo-p-xylene and dibromotetrafluoro-p-xylene to produce N-type and F-type parylene films. FTIR, XPS, thermal stability, and electrical studies show that the F-type parylene films grown from the precursors are comparable to, or sometimes better than, the films grown from dimer, and have potential microelectronics applications.

Platinum 11 at.% vanadium undergoes an ordering transformation to form a Pt8V superlattice. Deformation of the alloy results in the formation of single dislocations or superdislocations, depending on the degree of order. The superdislocations take the form of triple dislocations with a separation of 20 nm in the fully ordered alloy.

Twenty-eight cemented Muller straight femoral stems of titanium forged alloys were mainly revised for causing pain in the patient. The pain pattern differed from aseptic loosening and pain recurred only 14.5 months on average after implantation. The character of pain was dull, permanent, and increased at rest. Some patients reported pain relief while walking. Revisions were performed on average 25.5 months after primary implantation. Data from medical records, radiographs, histology of tissues taken at revision surgery, intraoperative pH measurements, examination of retrieved stems and bone cement fragments were gathered. In the radiographs debonding was visible only in 3 cases; a spindle shaped thickening of the femora occurred 9 months on average after recurrence of pain. After a further 11 months (average), scalloping osteolyses appeared. Abraded particles like metallic titanium alloy, titanium corrosion products, polymethylmethacrylate, xray contrast medium, and polyethylene were detected. Metallic particles dominated in the joint capsule whereas more corrosion products impregnated the cement to bone interface. The distal surfaces of the stems were corroded at a higher rate, whereas the proximal regions more often were subject to abrasion. Measurements of the pH of the corroded stems revealed values of high acidity. Recurrence of pain and subperiosteal apposition of bone are due to diffusion of acid; subsequent scalloping osteolyses develop due to particle induced foreign body granulomas. The mechanism of crevice corrosion of cemented titanium based alloys does not seem applicable to cobalt and iron based implant alloys. Titanium alloys can no longer be recommended for cementation, but are as safe as ever for anchorage without cement.

High-resolution (0.005/cm) FTIR spectra of the X2Pi(i)-X2Pi(i) (1-0) rovibrational bands of (C-35)(O-16) and (Cl-37)(O-16) were obtained in 1 torr of helium carrier gas. After measuring the strengths of approximately 830 individual IR lines from several spectra, a total band strength of 13.1 + or - 1.1/sq cm atm and a first Herman-Wallis coefficient of (4.12 + or - 0.62) x 10 to the -3rd were determined.

The effects of potassium or sodium added as the cyclohexanebutyrate and of potassium added as the Conostan standard, on the absorbance of vanadium present as vanadyl tetraphenylporphyrin, acetylacetonate, or benzoylacetonate, or as Conostan vanadium standard in xylene solutions, or in real petroleum samples are described. The effect of the alkali metal depends both on the kind of vanadium compound and on the type of alkali metal compound added. There is no analogy between the behaviour of vanadium in aqueous and xylene solutions containing large amounts of easily ionizable metal. Addition of potassium (or sodium) for the determination of vanadium in xylene solutions cannot be recommended.

The gas-phase photolysis of 2-methyl-1,3-butadiene has been investigated using krypton (123.6 nm) resonance radiation. The observed neutral products of the primary decomposition were vinylacetylene, ethylene, acetylene, methylacetylene, propylene, allene, 2-methy-1-buten-3-yne, pentatriene/1-penten-3-yne, 1,3-butadiene, 2-butyne and butatriene, listed in decreasing order of concentration. There was also evidence of the presence of several radical fragments: CH2/CH3, C2H3, C3H3, and C4H5. Quantum yields for each of the products were determined in the photolysis of 2-methyl-1,3-butadiene, performed both in the presence and the absence of additives. Nitric oxide and oxygen were employed as radical scavengers, while hydrogen sulfide and hydrogen iodide were used as radical interceptors. Twelve primary, neutral molecule, reaction channels were proposed and the quantum efficiency assigned for each. The ionization efficiency of 2-methyl-1,3-butadiene was established as n = 0.55 at 10.03 eV. No products formed exclusively via an ion–molecule pathway were identified and therefore the fate of the C5H8+ ion was not determined.

Some atomic absorption characteristics of xylene solutions of eight organometallic compounds of nickel in air—acetylene and nitrous oxide—acetylene flames are described. Different absorbances from various nickel organometallic compounds were observed; these differences were not eliminated by using the nitrous oxide—acetylene flame. Serious errors may arise when different organometallic compounds are used for calibration in the determination of nickel in xylene solutions of various petroleum samples. These errors are much less pronounced when nickel is determined by a standard addition technique. The effects of different sample matrices are discussed.

The effect of the type of organometallic iron or copper compounds on the value of the absorbance signals of these metals in an air-acetylene flame and for iron in a dinitrogen oxide-acetylene flame is reported. The determination of iron and copper in xylene solutions of the asphaltene and resinous petroleum fractions was carried out using various organometallic compounds of both metals as standards and by both the calibration graph and standard additions techniques. There are serious limitations to the direct flame atomic-absorption spectrometric methods, owing to transport interferences. In addition, with iron, there are matrix interferences caused by the structure of the petroleum samples being analysed and also owing to the various forms of iron present in these samples. It is recommended that determination of these elements in heavy petroleum fractions should be carried out by dry mineralisation and flame atomic-absorption spectrometric analysis of aqueous solutions.

Coronary-angiographic studies and autoptic findings [1–10] have demonstrated a major role of coronary thrombus formation in the pathomechanisms leading to acute coronary syndromes like unstable angina and acute myocardial infarction. Furthermore, it has been shown that 30–70% of patients with coronary artery disease (CAD) exhibit elevated levels of the fast-acting inhibitor of tissue plasminogen activator (PAI-1) [11–16]. Therefore, it has been discussed whether these findings might explain an increased thrombotic risk by impairment of the total fibrinolytic potential or whether elevations of PAI-1 levels are age-related [17, 18] or a reactive phenomenon due to recurrent chest pain and other stress factors [19, 20]. Indeed, it has been shown that PAI-1 elevation can be caused by a wide spectrum of diseases which are not related to thromboembolic events [20, 21].

Spatially resolved matrix isolation spectroscopy, in which each position on a rigid, low temperature matrix is subjected to a different photolysis wavelength, was used to ascertain in a single experiment, the wavelength of dependence of the Cr(CO)5+CO and Cr(CO)4+CO photoassociation reactions in an Ar matrix. Relative quantum yields closely followed the absorption spectra of the individual carbonyl fragments.