Impact of the healthcare payment system on patient access to oral anticancer drugs: an illustration from the French and United States contexts

PubMed Central

2014-01-01

Background Oral anticancer drugs (OADs) allow treating a growing range of cancers. Despite their convenience, their acceptance by healthcare professionals and patients may be affected by medical, economical and organizational factors. The way the healthcare payment system (HPS) reimburses OADs or finances hospital activities may impact patients’ access to such drugs. We discuss how the HPS in France and USA may generate disincentives to the use of OADs in certain circumstances. Discussion French public and private hospitals are financed by National Health Insurance (NHI) according to the nature and volume of medical services provided annually. Patients receiving intravenous anticancer drugs (IADs) in a hospital setting generate services, while those receiving OADs shift a part of service provision from the hospital to the community. In 2013, two million outpatient IADs sessions were performed, representing a cost of €815 million to the NHI, but positive contribution margin of €86 million to hospitals. Substitution of IADs by OADs mechanically induces a shortfall in hospital income related to hospitalizations. Such economic constraints may partially contribute to making physicians reluctant to prescribe OADs. In the US healthcare system, coverage for OADs is less favorable than coverage for injectable anticancer drugs. In 2006, a Cancer Drug Coverage Parity Act was adopted by several states in order to provide patients with better coverage for OADs. Nonetheless, the complexity of reimbursement systems and multiple reimbursement channels from private insurance represent real economic barriers which may prevent patients with low income being treated with OADs. From an organizational perspective, in both countries the use of OADs generates additional activities related to physician consultations, therapeutic education and healthcare coordination between hospitals and community settings, which are not considered in the funding of hospitals activities so far. Summary Funding of healthcare services is a critical factor influencing in part the choice of cancer treatments and this is expected to become increasingly important as economic constraints grow. Drug reimbursement systems and hospital financing changes, coupled with other accompanying measures, should contribute to improve equal and safe patient access to appropriate anticancer drugs and improve the management and care pathway of cancer patients. PMID:24950778

Safety and efficacy of once-weekly semaglutide vs additional oral antidiabetic drugs in Japanese people with inadequately controlled type 2 diabetes: A randomized trial.

PubMed

Kaku, Kohei; Yamada, Yuichiro; Watada, Hirotaka; Abiko, Atsuko; Nishida, Tomoyuki; Zacho, Jeppe; Kiyosue, Arihiro

2018-05-01

To evaluate the safety and efficacy of once-weekly subcutaneous semaglutide as monotherapy or combined with an oral antidiabetic drug (OAD) vs an additional OAD added to background therapy in Japanese people with type 2 diabetes (T2D) inadequately controlled on diet/exercise or OAD monotherapy. In this phase III, open-label trial, adults with T2D were randomized 2:2:1 to semaglutide 0.5 mg or 1.0 mg, or one additional OAD (a dipeptidyl peptidase-4 inhibitor, biguanide, sulphonylurea, glinide, α-glucosidase inhibitor or thiazolidinedione) with a different mode of action from that of background therapy. The primary endpoint was number of adverse events (AEs) after 56 weeks. Baseline characteristics were balanced between treatment arms (601 randomized). More AEs were reported in the semaglutide 0.5 mg (86.2%) and 1.0 mg (88.0%) groups than in the additional OAD group (71.7%). These were typically mild/moderate. Gastrointestinal AEs were most frequent with semaglutide, which diminished over time. The mean glycated haemoglobin (HbA1c) concentration (baseline 8.1%) was significantly reduced with semaglutide 0.5 mg and 1.0 mg vs additional OAD (1.7% and 2.0% vs 0.7%, respectively; estimated treatment difference [ETD] vs additional OAD -1.08% and -1.37%, both P < .0001). Body weight (baseline 71.5 kg) was reduced by 1.4 kg and 3.2 kg with semaglutide 0.5 mg and 1.0 mg, vs a 0.4-kg increase with additional OAD (ETD -1.84 kg and -3.59 kg; both P < .0001). For semaglutide-treated participants, >80% achieved an HbA1c concentration <7.0% (Japanese Diabetes Society target). Semaglutide was well tolerated, with no new safety issues identified. Semaglutide treatment significantly reduced HbA1c and body weight vs additional OAD treatment in Japanese people with T2D. © 2018 The Authors. Diabetes, Obesity and Metabolism published by John Wiley & Sons Ltd.

A catalyst-free achieving of N-doped carbon nanotubes: The healing of single-vacancy defects by NO molecule

NASA Astrophysics Data System (ADS)

Esrafili, Mehdi D.; Saeidi, Nasibeh

2018-01-01

Density functional theory calculations are performed to study the healing mechanism of single-vacancy defects in zigzag (n,0) CNTs by NO molecule (n = 6,8,10). The results indicate that the healing process proceeds through a two-step mechanism. First, NO molecule adsorbs over the defective site. Then, the extra oxygen atom (Oads) is eliminated by three different ways: (i) NO + Oads → NO2, (ii) CO + Oads → CO2, or (iii) SO2 + Oads → SO3. The dependency of the healing process on the tube diameter is studied in detail. The results of this work suggest a novel approach to achieve N-doped CNTs.

Biochemical and genetic characterization of the Enterococcus faecalis oxaloacetate decarboxylase complex.

PubMed

Repizo, Guillermo D; Blancato, Víctor S; Mortera, Pablo; Lolkema, Juke S; Magni, Christian

2013-05-01

Enterococcus faecalis encodes a biotin-dependent oxaloacetate decarboxylase (OAD), which is constituted by four subunits: E. faecalis carboxyltransferase subunit OadA (termed Ef-A), membrane pump Ef-B, biotin acceptor protein Ef-D, and the novel subunit Ef-H. Our results show that in E. faecalis, subunits Ef-A, Ef-D, and Ef-H form a cytoplasmic soluble complex (termed Ef-AHD) which is also associated with the membrane. In order to characterize the role of the novel Ef-H subunit, coexpression of oad genes was performed in Escherichia coli, showing that this subunit is vital for Ef-A and Ef-D interaction. Diminished growth of the oadA and oadD single deletion mutants in citrate-supplemented medium indicated that the activity of the complex is essential for citrate utilization. Remarkably, the oadB-deficient strain was still capable of growing to wild-type levels but with a delay during the citrate-consuming phase, suggesting that the soluble Ef-AHD complex is functional in E. faecalis. These results suggest that the Ef-AHD complex is active in its soluble form, and that it is capable of interacting in a dynamic way with the membrane-bound Ef-B subunit to achieve its maximal alkalinization capacity during citrate fermentation.

Evaluation of methods to estimate missing days' supply within pharmacy data of the Clinical Practice Research Datalink (CPRD) and The Health Improvement Network (THIN).

PubMed

Lum, Kirsten J; Newcomb, Craig W; Roy, Jason A; Carbonari, Dena M; Saine, M Elle; Cardillo, Serena; Bhullar, Harshvinder; Gallagher, Arlene M; Lo Re, Vincent

2017-01-01

The extent to which days' supply data are missing in pharmacoepidemiologic databases and effective methods for estimation is unknown. We determined the percentage of missing days' supply on prescription and patient levels for oral anti-diabetic drugs (OADs) and evaluated three methods for estimating days' supply within the Clinical Practice Research Datalink (CPRD) and The Health Improvement Network (THIN). We estimated the percentage of OAD prescriptions and patients with missing days' supply in each database from 2009 to 2013. Within a random sample of prescriptions with known days' supply, we measured the accuracy of three methods to estimate missing days' supply by imputing the following: (1) 28 days' supply, (2) mode number of tablets/day by drug strength and number of tablets/prescription, and (3) number of tablets/day via a machine learning algorithm. We determined incidence rates (IRs) of acute myocardial infarction (AMI) using each method to evaluate the impact on ascertainment of exposure time and outcomes. Days' supply was missing for 24 % of OAD prescriptions in CPRD and 33 % in THIN (affecting 48 and 57 % of patients, respectively). Methods 2 and 3 were very accurate in estimating days' supply for OADs prescribed at a consistent number of tablets/day. Method 3 was more accurate for OADs prescribed at varying number of tablets/day. IRs of AMI were similar across methods for most OADs. Missing days' supply is a substantial problem in both databases. Method 2 is easy and very accurate for most OADs and results in IRs comparable to those from method 3.

Clinical and Economic Outcomes Associated With the Timing of Initiation of Basal Insulin in Patients With Type 2 Diabetes Mellitus Previously Treated With Oral Antidiabetes Drugs.

PubMed

Levin, Philip; Zhou, Steve; Durden, Emily; Farr, Amanda M; Gill, Jasvinder; Wei, Wenhui

2016-01-01

In patients with type 2 diabetes mellitus (T2DM) not achieving glycemic targets using oral antidiabetes drugs (OADs), studies suggest that timely insulin initiation has clinical benefits. Insulin initiation at the early versus late stage of disease progression has not been explored in detail. This retrospective database analysis investigated clinical and economic outcomes associated with the timing of insulin initiation in patients with T2DM treated with ≥1 OAD in a real-world US setting. This study linked data from the Truven Health MarketScan(®) Commercial database, Medicare Supplemental database, and Quintiles Electronic Medical Records database. A total of 1830 patients with T2DM were included. Patients were grouped according to their OAD use before basal insulin initiation (1, 2, or ≥3 OADs) as a proxy for the timing of insulin initiation. Clinical and economic outcomes were evaluated over 1 year of follow-up. During follow-up the 1 OAD group, compared with the 2 and ≥3 OADs groups, had a greater reduction in glycosylated hemoglobin A1c (-1.7% vs -1.0% vs -0.9%, respectively; P < 0.0001), greater achievement of glycemic target (38.2% vs 26.7% vs 19.6%, respectively; P < 0.0001), and a lower incidence of hypoglycemia (2.7% vs 6.6% vs 5.0%, respectively; P = 0.0002), with no difference in total health care costs ($21,167 vs $21,060 vs $20,133, respectively). This study shows that early insulin initiation (represented by the 1 OAD group) may be clinically beneficial to patients with T2DM not controlled with OADs, without adding to costs. This supports the call for timely initiation of individualized insulin therapy in this population. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Initiation of insulin glargine therapy in type 2 diabetes subjects suboptimally controlled on oral antidiabetic agents: results from the AT.LANTUS trial.

PubMed

Davies, M; Lavalle-González, F; Storms, F; Gomis, R

2008-05-01

For many patients with type 2 diabetes, oral antidiabetic agents (OADs) do not provide optimal glycaemic control, necessitating insulin therapy. Fear of hypoglycaemia is a major barrier to initiating insulin therapy. The AT.LANTUS study investigated optimal methods to initiate and maintain insulin glargine (LANTUS, glargine, Sanofi-aventis, Paris, France) therapy using two treatment algorithms. This subgroup analysis investigated the initiation of once-daily glargine therapy in patients suboptimally controlled on multiple OADs. This study was a 24-week, multinational (59 countries), multicenter (611), randomized study. Algorithm 1 was a clinic-driven titration and algorithm 2 was a patient-driven titration. Titration was based on target fasting blood glucose < or =100 mg/dl (< or =5.5 mmol/l). Algorithms were compared for incidence of severe hypoglycaemia [requiring assistance and blood glucose <50 mg/dl (<2.8 mmol/l)] and baseline to end-point change in haemoglobin A(1c) (HbA(1c)). Of the 4961 patients enrolled in the study, 865 were included in this subgroup analysis: 340 received glargine plus 1 OAD and 525 received glargine plus >1 OAD. Incidence of severe hypoglycaemia was <1%. HbA(1c) decreased significantly between baseline and end-point for patients receiving glargine plus 1 OAD (-1.4%, p < 0.001; algorithm 1 -1.3% vs. algorithm 2 -1.5%; p = 0.03) and glargine plus >1 OAD (-1.7%, p < 0.001; algorithm 1 -1.5% vs. algorithm 2 -1.8%; p = 0.001). This study shows that initiation of once-daily glargine with OADs results in significant reduction of HbA(1c) with a low risk of hypoglycaemia. The greater reduction in HbA(1c) was seen in patients randomized to the patient-driven algorithm (algorithm 2) on 1 or >1 OAD.

Characteristics of patients with type 2 diabetes mellitus newly treated with GLP-1 receptor agonists (CHADIG Study): a cross-sectional multicentre study in Spain

PubMed Central

Conget, Ignacio; Mauricio, Dídac; Ortega, Rafael; Detournay, Bruno

2016-01-01

Objective Several glucagon-like peptide-1 (GLP-1) receptor agonists (GLP-1Ra) have been made recently available in Spain for type 2 diabetes mellitus (DM2) treatment. There are no published data on the clinical and sociodemographic profile of patients initiating treatment with GLP-1Ra in Spain. Our objective was to understand these patients' characteristics in a real-world clinical practice setting. Design Cross-sectional observational study. Setting Spanish specialist outpatient clinics. Participants 403 adults with DM2 initiating GLP-1Ra treatment were included. Primary and secondary outcome measures Sociodemographic and DM2-related clinical data, including treatment at and after GLP-1Ra initiation and comorbidities, were collected. Results Evaluable patients (n=403; 50.9% female) were included (July 2013 to March 2014) at 24 centres by 53 specialists (47 endocrinology, 6 internal medicine), with the following profile (value±SD): age (58.3±10.4 years), diabetes duration (9.9±7 years), body mass index (BMI; 36.2±5.5) and glycated haemoglobin (HbA1c; 8.4±1.4%); 14% had HbA1c≤7%. Previous antidiabetic treatment: 53.8% only oral antidiabetic drugs (OADs), 5.2% insulin and 40% insulin and OAD; of those receiving OAD, 35% single drug, 38.2% 2 drugs and 24% 3 drugs. Concomitant to GLP-1Ra, 55.3% were only on OAD, 36.2% on insulin and OAD, and 7.2% only on insulin. Of those receiving OAD, the GLP-1Ra was mainly associated with 1 drug (65%) or 2 drugs (31.8%). GLP-1Ra are frequently added to existing antidiabetic drugs, with dipeptidyl peptidase-4 inhibitors being the OAD most frequently switched (45% receiving 1 before starting GLP-1Ra, only 2.7% receiving it concomitantly). Conclusions In Spain, GLP-1Ra therapy is usually started in combination with OADs or OADs and insulin. These drugs are used in relatively young patients often not reaching therapeutic goals with other treatment combinations, roughly a decade after diagnosis and with a relatively high BMI. The latter could be explained by Spanish regional payers limiting reimbursed prescription to patients with a minimum BMI threshold (>30 in most regions, >35 in some). PMID:27466235

Portuguese Language Expertise Center for the OAD

NASA Astrophysics Data System (ADS)

Doran, Rosa; Canas, Lina; Anjos, Sara; Heenatigala, Thilina; Retrê, João; Afonso, José; Alves, Ana

2016-10-01

Supporting the use of astronomy as a tool for development in specific regions and languages, the International Astronomical Union's (IAU) Office of Astronomy for Development (OAD) has established a Portuguese `Language Expertise Centre for the OAD' (PLOAD), hosted at Núcleo Interactivo de Astronomia (NUCLIO), in collaboration with the Institute of Astrophysics and Space Sciences (IA) in Portugal. The centre is one of the new coordinating offices announced at the IAU General Assembly in Honolulu, Hawaii on 13 August 2015.

The IAU Office of Astronomy Development

NASA Astrophysics Data System (ADS)

Mauduit, Jean-Christophe; Govender, K.

2014-01-01

The International Astronomical Union (IAU), the largest body of professional astronomers in the world, has set up the Office of Astronomy for Development (OAD) in partnership with the South African National Research Foundation (NRF). The OAD is located at the South African Astronomical Observatory (SAAO) in Cape Town. Its mission is to realise the IAU's Strategic Plan, which aims to use astronomy as a tool for development. It focuses on the following three main areas: "Universities and Research", "Children and Schools" and "Public Outreach". Eighteen projects worldwide have been funded for 2013 and are currently under way. More will be starting in 2014. The OAD is also setting up regional nodes and language expertise centres around the world. This presentation will describe the ongoing activities of the OAD and plans for the future.

Showing the Way: Oncolytic Adenoviruses as Chaperones of Immunostimulatory Adjuncts.

PubMed

Huang, Jing Li; LaRocca, Christopher J; Yamamoto, Masato

2016-09-19

Oncolytic adenoviruses (OAds) are increasingly recognized as vectors for immunotherapy in the treatment of various solid tumors. The myriads of advantages of using adenovirus include targeted specificity upon infection and selective replication, which lead to localized viral burst, exponential spread of OAds, and antitumor effect. OAds can also induce a strong immune reaction due to the massive release of tumor antigens upon cytolysis and the presence of viral antigens. This review will highlight recent advances in adenoviral vectors expressing immunostimulatory effectors, such as GM-CSF (granulocyte macrophage colony-stimulating factor), interferon-α, interleukin-12, and CD40L. We will also discuss the combination of OAds with other immunotherapeutic strategies and describe the current understanding of how adenoviral vectors interact with the immune system to eliminate cancer cells.

Efficacy of Continuous Dosing of Tadalafil Once Daily vs Tadalafil On Demand in Clinical Subgroups of Men With Erectile Dysfunction: A Descriptive Comparison Using the Integrated Tadalafil Databases.

PubMed

Brock, Gerald; Ni, Xiao; Oelke, Matthias; Mulhall, John; Rosenberg, Matt; Seftel, Allen; D'Souza, Deborah; Barry, Jane

2016-05-01

Various factors play a role in the development of erectile dysfunction (ED). To provide a descriptive comparison of erectile function response for tadalafil on-demand (PRN) and once-daily (OAD) dosing regimens in patients with common comorbid conditions, treatments, or risk factors that can be considered when treating ED. In total, 17 PRN and 4 OAD placebo-controlled studies were included in the integrated database in these pooled analyses. Data were analyzed from patients treated with placebo, tadalafil 10 mg (low dose), and 20 mg (high dose) for the PRN studies and placebo, tadalafil 2.5 mg (low dose), and 5 mg (high dose) for the OAD studies. The effects of tadalafil were measured using the International Index of Erectile Function administered from baseline to week 12. A descriptive comparison of the efficacy of tadalafil PRN vs OAD was examined in the clinical populations. Baseline characteristics of 4,354 men were comparable between the PRN and OAD groups, with differences seen only in the variables of race, body mass index (BMI) of at least 30 kg/m(2), and alcohol use. Tadalafil was efficacious at improving erectile function for all clinical populations, except for the low-dose OAD group, which demonstrated a weaker effect vs placebo than the high-dose OAD group, and the low- and high-dose PRN groups vs placebo for patients with BMI of at least 30 kg/m(2) for patients without a cardiovascular disorder, smokers, patients with ED duration shorter than 1 year, and patients without previous phosphodiesterase type 5 inhibitor use. Tadalafil was efficacious for patients with or without diabetes mellitus, arterial hypertension, hyperlipidemia, and alcohol use at baseline. Tadalafil OAD and PRN regimens showed efficacy in patients with ED. No clinical populations of patients with ED seemed to benefit overwhelmingly from one dose regimen over the other. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Effects of vildagliptin as add-on treatment in patients with type 2 diabetes mellitus: insights from long-term clinical studies in Japan.

PubMed

Odawara, Masato; Sagara, Rieko

2015-01-01

Vildagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor, is wildly used to treat type 2 diabetes mellitus (T2DM) with mono- or combination-therapy. We review two previously published open-label studies to extract insights on the long-term efficacy and safety of vildagliptin. Two studies were conducted in Japan to assess the efficacy and safety of vildagliptin as an add-on to other oral antidiabetes drugs (OADs) for 52 weeks. These studies were performed under the similar protocol in Japanese patients with T2DM who were inadequately controlled with OAD monotherapy [excluding other dipeptidyl peptidase-4 (DPP-4) inhibitors]. Addition of vildagliptin (50 mg twice daily) to other OAD monotherapy [sulfonylurea (SU), metformin, thiazolidinedione, alpha-glucosidase inhibitor and glinide] reduced glycated hemoglobin (HbA1c) levels by -0.64 %,-0.75 %,-0.92 %,-0.94 % and - 0.64 %, respectively, over 52 weeks of treatment. Overall, the incidence of hypoglycemia was low and was slightly higher in the add-on to SU treatment group compared with the other groups. The incidences of adverse events were comparable among the treatment groups, and vildagliptin was well-tolerated as add-on therapy to other OADs. The evidence from the two studies indicates that vildagliptin as an add-on therapy to other OADs is a clinically reasonable option for Japanese patients with T2DM who respond inadequately to other OAD monotherapy.

The phenotypic spectrum of organic acidurias and urea cycle disorders. Part 2: the evolving clinical phenotype.

PubMed

Kölker, Stefan; Valayannopoulos, Vassili; Burlina, Alberto B; Sykut-Cegielska, Jolanta; Wijburg, Frits A; Teles, Elisa Leão; Zeman, Jiri; Dionisi-Vici, Carlo; Barić, Ivo; Karall, Daniela; Arnoux, Jean-Baptiste; Avram, Paula; Baumgartner, Matthias R; Blasco-Alonso, Javier; Boy, S P Nikolas; Rasmussen, Marlene Bøgehus; Burgard, Peter; Chabrol, Brigitte; Chakrapani, Anupam; Chapman, Kimberly; Cortès I Saladelafont, Elisenda; Couce, Maria L; de Meirleir, Linda; Dobbelaere, Dries; Furlan, Francesca; Gleich, Florian; González, Maria Julieta; Gradowska, Wanda; Grünewald, Stephanie; Honzik, Tomas; Hörster, Friederike; Ioannou, Hariklea; Jalan, Anil; Häberle, Johannes; Haege, Gisela; Langereis, Eveline; de Lonlay, Pascale; Martinelli, Diego; Matsumoto, Shirou; Mühlhausen, Chris; Murphy, Elaine; de Baulny, Hélène Ogier; Ortez, Carlos; Pedrón, Consuelo C; Pintos-Morell, Guillem; Pena-Quintana, Luis; Ramadža, Danijela Petković; Rodrigues, Esmeralda; Scholl-Bürgi, Sabine; Sokal, Etienne; Summar, Marshall L; Thompson, Nicholas; Vara, Roshni; Pinera, Inmaculada Vives; Walter, John H; Williams, Monique; Lund, Allan M; Garcia-Cazorla, Angeles; Garcia Cazorla, Angeles

2015-11-01

The disease course and long-term outcome of patients with organic acidurias (OAD) and urea cycle disorders (UCD) are incompletely understood. To evaluate the complex clinical phenotype of OAD and UCD patients at different ages. Acquired microcephaly and movement disorders were common in OAD and UCD highlighting that the brain is the major organ involved in these diseases. Cardiomyopathy [methylmalonic (MMA) and propionic aciduria (PA)], prolonged QTc interval (PA), optic nerve atrophy [MMA, isovaleric aciduria (IVA)], pancytopenia (PA), and macrocephaly [glutaric aciduria type 1 (GA1)] were exclusively found in OAD patients, whereas hepatic involvement was more frequent in UCD patients, in particular in argininosuccinate lyase (ASL) deficiency. Chronic renal failure was often found in MMA, with highest frequency in mut(0) patients. Unexpectedly, chronic renal failure was also observed in adolescent and adult patients with GA1 and ASL deficiency. It had a similar frequency in patients with or without a movement disorder suggesting different pathophysiology. Thirteen patients (classic OAD: 3, UCD: 10) died during the study interval, ten of them during the initial metabolic crisis in the newborn period. Male patients with late-onset ornithine transcarbamylase deficiency were presumably overrepresented in the study population. Neurologic impairment is common in OAD and UCD, whereas the involvement of other organs (heart, liver, kidneys, eyes) follows a disease-specific pattern. The identification of unexpected chronic renal failure in GA1 and ASL deficiency emphasizes the importance of a systematic follow-up in patients with rare diseases.

Three outer arm dynein heavy chains of Chlamydomonas reinhardtii operate in a coordinated fashion both in vitro and in vivo.

PubMed

Takazaki, Hiroko; Liu, Zhongmei; Jin, Mingyue; Kamiya, Ritsu; Yasunaga, Takuo

2010-07-01

Outer arm dynein (OAD) in cilia and flagella contains two to three nonidentical heavy chains (HCs) that possess motor activity. In Chlamydomonas, flagellar OAD contains three HCs, alpha-, beta-, and gamma-HCs, each appearing to have a distinct role. To determine the precise molecular mechanism of their function, cross-sectional electron micrographs of wild-type and single HC-disruption mutants were compared and statistically analyzed. While the alpha-HC mutant displayed an OAD of lower density, which was attributed to a lack of alpha-HC, the OAD of beta- and gamma-HC mutants not only lacked the corresponding HC, but was also significantly affected in its structure, particularly with respect to the localization of alpha-HC. The lack of beta-HC induced mislocalization of alpha-HC, while a disruption of the gamma-HC gene resulted in the synchronized movement of alpha-HC and beta-HC in the manners for stacking. Interestingly, using cryo-electron microscopy, purified OADs were typically observed consisting of two stacked heads and an independent single head, which presumably corresponded to gamma-HC. This conformation is different from previous reports in which the three HCs displayed a stacked form in flagella observed by cryo-electron tomography and a bouquet structure on mica in deep-etch replica images. These results suggest that gamma-HC supports the tight stacking arrangement of inter or intra alpha-/beta-HC to facilitate the proper functioning of OAD. 2010 Wiley-Liss, Inc.

Characteristics of patients with type 2 diabetes mellitus newly treated with GLP-1 receptor agonists (CHADIG Study): a cross-sectional multicentre study in Spain.

PubMed

Conget, Ignacio; Mauricio, Dídac; Ortega, Rafael; Detournay, Bruno

2016-07-26

Several glucagon-like peptide-1 (GLP-1) receptor agonists (GLP-1Ra) have been made recently available in Spain for type 2 diabetes mellitus (DM2) treatment. There are no published data on the clinical and sociodemographic profile of patients initiating treatment with GLP-1Ra in Spain. Our objective was to understand these patients' characteristics in a real-world clinical practice setting. Cross-sectional observational study. Spanish specialist outpatient clinics. 403 adults with DM2 initiating GLP-1Ra treatment were included. Sociodemographic and DM2-related clinical data, including treatment at and after GLP-1Ra initiation and comorbidities, were collected. Evaluable patients (n=403; 50.9% female) were included (July 2013 to March 2014) at 24 centres by 53 specialists (47 endocrinology, 6 internal medicine), with the following profile (value±SD): age (58.3±10.4 years), diabetes duration (9.9±7 years), body mass index (BMI; 36.2±5.5) and glycated haemoglobin (HbA1c; 8.4±1.4%); 14% had HbA1c≤7%. Previous antidiabetic treatment: 53.8% only oral antidiabetic drugs (OADs), 5.2% insulin and 40% insulin and OAD; of those receiving OAD, 35% single drug, 38.2% 2 drugs and 24% 3 drugs. Concomitant to GLP-1Ra, 55.3% were only on OAD, 36.2% on insulin and OAD, and 7.2% only on insulin. Of those receiving OAD, the GLP-1Ra was mainly associated with 1 drug (65%) or 2 drugs (31.8%). GLP-1Ra are frequently added to existing antidiabetic drugs, with dipeptidyl peptidase-4 inhibitors being the OAD most frequently switched (45% receiving 1 before starting GLP-1Ra, only 2.7% receiving it concomitantly). In Spain, GLP-1Ra therapy is usually started in combination with OADs or OADs and insulin. These drugs are used in relatively young patients often not reaching therapeutic goals with other treatment combinations, roughly a decade after diagnosis and with a relatively high BMI. The latter could be explained by Spanish regional payers limiting reimbursed prescription to patients with a minimum BMI threshold (>30 in most regions, >35 in some). Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Variance in total levels of phospholipase C zeta (PLC-ζ) in human sperm may limit the applicability of quantitative immunofluorescent analysis as a diagnostic indicator of oocyte activation capability.

PubMed

Kashir, Junaid; Jones, Celine; Mounce, Ginny; Ramadan, Walaa M; Lemmon, Bernadette; Heindryckx, Bjorn; de Sutter, Petra; Parrington, John; Turner, Karen; Child, Tim; McVeigh, Enda; Coward, Kevin

2013-01-01

To examine whether similar levels of phospholipase C zeta (PLC-ζ) protein are present in sperm from men whose ejaculates resulted in normal oocyte activation, and to examine whether a predominant pattern of PLC-ζ localization is linked to normal oocyte activation ability. Laboratory study. University laboratory. Control subjects (men with proven oocyte activation capacity; n = 16) and men whose sperm resulted in recurrent intracytoplasmic sperm injection failure (oocyte activation deficient [OAD]; n = 5). Quantitative immunofluorescent analysis of PLC-ζ protein in human sperm. Total levels of PLC-ζ fluorescence, proportions of sperm exhibiting PLC-ζ immunoreactivity, and proportions of PLC-ζ localization patterns in sperm from control and OAD men. Sperm from control subjects presented a significantly higher proportion of sperm exhibiting PLC-ζ immunofluorescence compared with infertile men diagnosed with OAD (82.6% and 27.4%, respectively). Total levels of PLC-ζ in sperm from individual control and OAD patients exhibited significant variance, with sperm from 10 out of 16 (62.5%) exhibiting levels similar to OAD samples. Predominant PLC-ζ localization patterns varied between control and OAD samples with no predictable or consistent pattern. The results indicate that sperm from control men exhibited significant variance in total levels of PLC-ζ protein, as well as significant variance in the predominant localization pattern. Such variance may hinder the diagnostic application of quantitative PLC-ζ immunofluorescent analysis. Copyright © 2013 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Estimating the Time Interval Between Exposure to the World Trade Center Disaster and Incident Diagnoses of Obstructive Airway Disease

PubMed Central

Glaser, Michelle S.; Webber, Mayris P.; Zeig-Owens, Rachel; Weakley, Jessica; Liu, Xiaoxue; Ye, Fen; Cohen, Hillel W.; Aldrich, Thomas K.; Kelly, Kerry J.; Nolan, Anna; Weiden, Michael D.; Prezant, David J.; Hall, Charles B.

2014-01-01

Respiratory disorders are associated with occupational and environmental exposures. The latency period between exposure and disease onset remains uncertain. The World Trade Center (WTC) disaster presents a unique opportunity to describe the latency period for obstructive airway disease (OAD) diagnoses. This prospective cohort study of New York City firefighters compared the timing and incidence of physician-diagnosed OAD relative to WTC exposure. Exposure was categorized by WTC arrival time as high (on the morning of September 11, 2001), moderate (after noon on September 11, 2001, or on September 12, 2001), or low (during September 13–24, 2001). We modeled relative rates and 95% confidence intervals of OAD incidence by exposure over the first 5 years after September 11, 2001, estimating the times of change in the relative rate with change point models. We observed a change point at 15 months after September 11, 2001. Before 15 months, the relative rate for the high- versus low-exposure group was 3.96 (95% confidence interval: 2.51, 6.26) and thereafter, it was 1.76 (95% confidence interval: 1.26, 2.46). Incident OAD was associated with WTC exposure for at least 5 years after September 11, 2001. There were higher rates of new-onset OAD among the high-exposure group during the first 15 months and, to a lesser extent, throughout follow-up. This difference in relative rate by exposure occurred despite full and free access to health care for all WTC-exposed firefighters, demonstrating the persistence of WTC-associated OAD risk. PMID:24980522

Psychopathology, temperament and unintentional injury: cross-sectional and longitudinal relationships.

PubMed

Rowe, Richard; Simonoff, Emily; Silberg, Judy L

2007-01-01

Growing evidence indicates a link between unintentional injury and both disruptive and emotional psychopathology. We present further evidence of these associations and address the underlying mechanisms. We also examine the genetic contribution to unintentional injury. The Virginia Twin Study of Adolescent Behavioral Development provides genetically informative multi-wave and multi-informant data regarding common psychopathology using the Child and Adolescent Psychiatric Assessment interview. The EASI temperament scales and child injury involvement were measured in parent-report questionnaires. Unintentional injury showed significant genetic effects in girls and significant shared environmental effects in boys and girls. Symptoms of over-anxious disorder (OAD), and the EASI temperament scales were independently associated with injury. Longitudinal modeling showed impulsivity and OAD symptoms were related prospectively to injury involvement. Injuries did not increase risk for later impulsivity or OAD symptoms but were related prospectively to separation anxiety disorder symptoms. Impulsivity and OAD symptoms increased risk of later injury. We discuss the processes that may be involved in these relationships.

Occupational obstructive airway diseases in Germany: Frequency and causes in an international comparison

DOE Office of Scientific and Technical Information (OSTI.GOV)

Latza, U.; Baur, X.

2005-08-01

Occupational inhalative exposures contribute to a significant proportion of obstructive airway diseases (OAD), namely chronic obstructive pulmonary disease (COPD) and asthma. The number of occupational OAD in the German industrial sector for the year 2003 are presented. Other analyses of surveillance data were retrieved from Medline. Most confirmed reports of OAD are cases of sensitizer induced occupational asthma (625 confirmed cases) followed by COPD in coal miners (414 cases), irritant induced occupational asthma (156 cases), and isocyanate asthma (54 cases). Main causes of occupational asthma in Germany comprise flour/flour constituents (35.9%), food/feed dust (9.0%), and isocyanates (6.5%). Flour and grainmore » dust is a frequent cause of occupational asthma in most European countries and South Africa. Isocyanates are still a problem worldwide. Although wide differences in the estimated incidences between countries exist due to deficits in the coverage of occupational OAD, the high numbers necessitate improvement of preventive measures.« less

The IAU Office of Astronomy for Development

NASA Astrophysics Data System (ADS)

Govender, Kevin

2015-03-01

The IAU Office of Astronomy for Development (OAD)†, established in March 2011 as part of the implementation of the IAU Strategic Plan, is currently located in South Africa and serves as a global coordinating centre for astronomy-for-development activities. In terms of structure the OAD is required to establish regional nodes (similar offices in different parts of the world which focus on a particular geographic or cultural region) and three task forces: (i) Astronomy for Universities and Research, (ii) Astronomy for Children and Schools, and (iii) Astronomy for the Public. This paper will describe the progress of the OAD towards the realisation of the vision `Astronomy for a better world'.

Effect of bromocriptine-QR on glycemic control in subjects with uncontrolled hyperglycemia on one or two oral anti-diabetes agents.

PubMed

Vinik, Aaron I; Cincotta, Anthony H; Scranton, Richard E; Bohannon, Nancy; Ezrokhi, Michael; Gaziano, J Michael

2012-01-01

To investigate the effect of Bromocriptine-QR on glycemic control in patients with type 2 diabetes whose glycemia is poorly controlled on one or two oral anti-diabetes agents. Five hundred fifteen Type 2 Diabetes Mellitus (T2DM) subjects (ages 18 to 80 and average body mass index [BMI] of 32.7) with baseline HbA1c ≥ 7.5 and on one or two oral anti-diabetes (OAD) medications (metformin, sulfonylurea, and/or thiazolidinediones) were randomized 2:1 to bromocriptine-QR (1.6 to 4.8 mg/day) or placebo for a 24 week treatment period. Study investigators were allowed to adjust, if necessary, subject anti-diabetes medications during the study to attempt to achieve glycemic control in case of glycemic deterioration. The impact of bromocriptine-QR treatment intervention on glycemic control was assessed in subjects on any one or two OADs (ALL treatment category) (N = 515), or on metformin with or without another OAD (Met/OAD treatment category) (N = 356), or on metformin plus a sulfonylurea (Met/SU treatment category) (N = 245) 1) by examining the between group difference in change from baseline a) concomitant OAD medication changes during the study, and b) HbA1c and 2) by determining the odds of reaching HbA1c of ≤ 7.0% on bromocriptine-QR versus placebo. Significantly more patients (approximately 1.5 to 2-fold more; P<.05) intensified concomitant anti-diabetes medication therapy during the study in the placebo versus the bromocriptine-QR arm. In subjects that did not change the intensity of the baseline diabetes therapy (72%), and that were on any one or two OADs (ALL), or on metformin with or without another OAD (Met/OAD), or on metformin plus sulfonylurea (Met/SU), the HbA1c change for bromocriptine-QR versus placebo was -0.47 versus +0.22 (between group delta of -0.69, P<.0001), -0.55 versus +0.26 (between group delta of -0.81, P<.0001) and -0.63 versus +0.20 (between group delta of -0.83, P<.0001) respectively, after 24 weeks on therapy. The odds ratio of reaching HbA1c of ≤ 7.0% was 6.50, 12.03 and 11.45 (P<.0002) for these three groups, respectively. In T2DM subjects whose hyperglycemia is poorly controlled on one or two oral agents, bromocriptine-QR therapy for 24 weeks can provide significant added improvement in glycemic control relative to adding placebo.

Time to and factors associated with insulin initiation in patients with type 2 diabetes mellitus.

PubMed

Machado-Alba, Jorge Enrique; Machado-Duque, Manuel Enrique; Moreno-Gutierrez, Paula Andrea

2015-03-01

Determine the time between the start of oral antidiabetic therapy (OAD) and the initiation of insulin therapy and to establish factors associated with insulin prescription among patients with type 2 diabetes mellitus (T2DM) in Colombia. Cohort, retrospective, population-based study. We identify patients with T2DM who started OAD therapy between 1 January 2007 and 31 December 2008, and a 5-year follow-up was performed. Kaplan-Meier survival analysis for time to start insulin therapy was generated and factors associated with insulin initiation were determined using logistic regression. A total of 1042 patients (52.4% women), mean age 63.4 years at the start of pharmacological treatment. After 5 years, 272 patients (26.1%) initiated insulin therapy. Using combination therapy of metformin and glibenclamide was associated with greater risk of insulin initiation (OR: 1.64, 95% CI: 1.12-2.40, p=0.010), while being a male over 45 years of age (OR: 0.59, 95% CI: 0.37-0.96, p=0.034) and initiating OAD therapy with metformin (OR: 0.30, 95% CI: 0.20-0.46, p<0.001) reduced the risk of insulin use. After 5 years of OAD treatment, 26.1% of people with T2DM started insulin therapy. Age, sex and type of initial OAD affected the probability of switching to insulin in these patients in Colombia. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Cost-effectiveness analysis of exenatide twice daily (BID) vs insulin glargine once daily (QD) as add-on therapy in Chinese patients with Type 2 diabetes mellitus inadequately controlled by oral therapies.

PubMed

Deng, Jing; Gu, Shuyan; Shao, Hui; Dong, Hengjin; Zou, Dajin; Shi, Lizheng

2015-01-01

To estimate cost-effectiveness of exenatide twice daily (BID) vs insulin glargine once daily (QD) as add-on therapy in Chinese type 2 diabetes patients not well controlled by oral anti-diabetic (OAD) agents. The Cardiff model was populated with data synthesized from three head-to-head randomized clinical trials of up to 30 weeks in China comparing exenatide BID vs insulin glargine as add-on therapies to oral therapies in the Chinese population. The Cardiff model generated outputs including macrovascular and microvascular complications, diabetes-specific mortality, costs, and quality-adjusted life years (QALYs). Cost and QALYs were estimated with a time horizon of 40 years at a discount rate of 3% from a societal perspective. Compared with insulin glargine plus OAD treatments, patients on exenatide BID plus OAD gained 1.88 QALYs, at an incremental cost saving of Chinese Renminbi (RMB) 114,593 (i.e., cost saving of RMB 61078/QALY). The cost-effectiveness results were robust to various sensitivity analyses including probabilistic sensitivity analysis. The variables with the most impact on incremental cost-effectiveness ratio included HbA1c level at baseline, health utilities decrement, and BMI at baseline. Compared with insulin glargine QD, exenatide BID as add-on therapy to OAD is a cost-effective treatment in Chinese patients inadequately controlled by OAD treatments.

Determinants of saxagliptin use among patients with type 2 diabetes mellitus treated with oral anti-diabetic drugs.

PubMed

Saine, M Elle; Carbonari, Dena M; Newcomb, Craig W; Nezamzadeh, Melissa S; Haynes, Kevin; Roy, Jason A; Cardillo, Serena; Hennessy, Sean; Holick, Crystal N; Esposito, Daina B; Gallagher, Arlene M; Bhullar, Harshvinder; Strom, Brian L; Lo Re, Vincent

2015-04-02

The patterns and determinants of saxagliptin use among patients with type 2 diabetes mellitus (T2DM) are unknown in real-world settings. We compared the characteristics of T2DM patients who were new initiators of saxagliptin to those who were new initiators of non-dipeptidyl peptidase-4 (DPP-4) inhibitor oral anti-diabetic drugs (OADs) and identified factors associated with saxagliptin use. We conducted a cross-sectional study within the Clinical Practice Research Datalink (CPRD), The Health Improvement Network (THIN), US Medicare, and the HealthCore Integrated Research Database (HIRD(SM)) across the first 36 months of saxagliptin availability (29 months for US Medicare). Patients were included if they were: 1) ≥18 years old, 2) newly prescribed saxagliptin or a non-DPP-4 inhibitor OAD, and 3) enrolled in their respective database for 180 days. For each saxagliptin initiator, we randomly selected up to ten non-DPP-4 inhibitor OAD initiators matched on age, sex, and geographic region. Conditional logistic regression was used to identify determinants of saxagliptin use. We identified 64,079 saxagliptin initiators (CPRD: 1,962; THIN: 2,084; US Medicare: 51,976; HIRD(SM): 8,057) and 610,660 non-DPP-4 inhibitor OAD initiators (CPRD: 19,484; THIN: 19,936; US Medicare: 493,432; HIRD(SM): 77,808). Across all four data sources, prior OAD use, hypertension, and hyperlipidemia were associated with saxagliptin use. Saxagliptin initiation was also associated with hemoglobin A1c results >8% within the UK data sources, and a greater number of hemoglobin A1c measurements in the US data sources. In these UK and US data sources, initiation of saxagliptin was associated with prior poor glycemic control, prior OAD use, and diagnoses of hypertension and hyperlipidemia. ClinicalTrials.gov identifiers NCT01086280 , NCT01086293 , NCT01086319 , NCT01086306 , and NCT01377935.

Efficacy and Safety of Tadalafil 5 mg Once Daily for the Treatment of Erectile Dysfunction After Robot-Assisted Laparoscopic Radical Prostatectomy: A 2-Year Follow-Up.

PubMed

Kim, Soodong; Sung, Gyung Tak

2018-03-27

Although nerve-sparing robot-assisted radical prostatectomy (NS-RALP) is performed, a large number of patients still experience erectile dysfunction (ED) after surgery. To evaluate the efficacy and safety of tadalafil 5 mg once daily (OaD) in ED treatment over 2 years and investigate the cause of vascular ED after NS-RARP. We retrospectively evaluated 95 men who underwent NS-RARP and had a penile rehabilitation treatment with tadalafil 5 mg OaD. They were classified into 3 groups: tadalafil 5 mg OaD for 2 years (group I), tadalafil 5 mg OaD for 1 year (group II), and no tadalafil (group III). All patients in group I underwent penile color duplex ultrasound to evaluate the cause of vascular ED. Patients were surveyed using the abridged 5-item International Index of Erectile Function (IIEF-5). Statistically significant improvements were observed in group I for all IIEF-5 domain scores (P = .000). There was no statistically significant difference in recovery of erectile function (EF) the 2-year follow-up between groups I and II. Sub-analysis based on NS status showed no difference in recovery of EF. However, group I showed better trends in EF improvement. Those with venogenic ED had poor responses compared with those with arteriogenic ED or unremarkable findings with tadalafil 5-mg OaD treatment (14.2% vs 55.0% vs 53.3%). The overall side effects included hot flushing in 9.5%, headache in 7.1%, and dizziness in 2.3% of patients. Long-term usage of tadalafil 5 mg OaD after RARP can be an effective option for penile rehabilitation. The present study is a retrospective study with a relatively small sample. Although the responses of patients with venogenic ED were limited compared with those with arteriogenic ED, tadalafil 5-mg OaD treatment was well tolerated and significantly improved EF up to 2 years after NS-RARP. Kim S, Sung GT. Efficacy and Safety of Tadalafil 5 mg Once Daily for the Treatment of Erectile Dysfunction After Robot-Assisted Laparoscopic Radical Prostatectomy: A 2-Year Follow-Up. Sex Med 2018;X:XXX-XXX. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

INCORPORATING ENVIRONMENTAL OUTCOMES INTO A HEALTH ECONOMIC MODEL.

PubMed

Marsh, Kevin; Ganz, Michael; Nørtoft, Emil; Lund, Niels; Graff-Zivin, Joshua

2016-01-01

Traditional economic evaluations for most health technology assessments (HTAs) have previously not included environmental outcomes. With the growing interest in reducing the environmental impact of human activities, the need to consider how to include environmental outcomes into HTAs has increased. We present a simple method of doing so. We adapted an existing clinical-economic model to include environmental outcomes (carbon dioxide [CO2] emissions) to predict the consequences of adding insulin to an oral antidiabetic (OAD) regimen for patients with type 2 diabetes mellitus (T2DM) over 30 years, from the United Kingdom payer perspective. Epidemiological, efficacy, healthcare costs, utility, and carbon emissions data were derived from published literature. A scenario analysis was performed to explore the impact of parameter uncertainty. The addition of insulin to an OAD regimen increases costs by 2,668 British pounds per patient and is associated with 0.36 additional quality-adjusted life-years per patient. The insulin-OAD combination regimen generates more treatment and disease management-related CO2 emissions per patient (1,686 kg) than the OAD-only regimen (310 kg), but generates fewer emissions associated with treating complications (3,019 kg versus 3,337 kg). Overall, adding insulin to OAD therapy generates an extra 1,057 kg of CO2 emissions per patient over 30 years. The model offers a simple approach for incorporating environmental outcomes into health economic analyses, to support a decision-maker's objective of reducing the environmental impact of health care. Further work is required to improve the accuracy of the approach; in particular, the generation of resource-specific environmental impacts.

Predictors for the initiation of a basal supported oral therapy (BOT) in type 2 diabetic patients under real-life conditions in Germany.

PubMed

Kostev, Karel; Dippel, Franz-Werner

2012-12-01

To assess the predictors for the initiation of a basal supported oral therapy (BOT) in type 2 diabetic patients under real-life conditions in Germany. A historical cohort study based on representative German real life data (IMS(®) Disease Analyzer) was performed. The study included patients with type 2 diabetes who started an oral antidiabetic drug (OAD) treatment between 01/1995 and 12/2011. Patients with consecutive treatment data for at least 12 months before the initiation of an OAD treatment were eligible for the analysis. The time-dependent rate of patients starting an insulin therapy with a long-acting insulin was calculated by use of the Kaplan-Meier method. Multivariate Cox regression analyses were applied to identify associated factors. The study included 194,967 patients with type 2 diabetes mellitus being on OAD therapy. 24,964 patients were switched to BOT during the observational period. The probability of switching to insulin therapy was associated with three main predictors such as (1) poor metabolic control, (2) midlife age and (3) number and type of the OAD before insulinization. The variation of the HbA1c threshold to HbA1c≥7.5 leads to comparable outcomes with significant HR. The highest probability of initiating a basal supported oral therapy (BOT) under real life conditions was found for patients with poor metabolic control, midlife age and pre-treatment with specific OADs such as SU, GLI or AGI before initiation of insulin therapy. Copyright © 2012 Primary Care Diabetes Europe. Published by Elsevier Ltd. All rights reserved.

77 FR 71131 - Implementation of the Middle Class Tax Relief and Job Creation Act of 2012; Establishment of a...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-29

... access to OADEs. Some OADEs are marketers that make autodialed calls on behalf of other entities, e.g... adopts the existing definition in its rules, as set forth in the TCPA context, and defines an ``emergency.... Definitions. As noted above, the Tax Relief Act does not define ``automatic dialing'' or ``robocall...

Understanding Motivations to Adopt Once-a-Day Milking amongst New Zealand Dairy Farmers

ERIC Educational Resources Information Center

Bewsell, D.; Clark, D. A.; Dalley, D. E.

2008-01-01

This paper reports the results of a study to understand why some New Zealand dairy farmers are changing from twice-a-day (TAD) to once-a-day (OAD) milking. Increasing herd size, unavailability of suitable labour and changing lifestyle expectations from farmers and their staff have led some to explore OAD milking as a means of alleviating these…

Obsessive-compulsive spectrum disorders: a comorbidity and family history perspective.

PubMed

Brakoulias, Vlasios; Starcevic, Vladan; Sammut, Peter; Berle, David; Milicevic, Denise; Moses, Karen; Hannan, Anthony

2011-04-01

The concept of obsessive-compulsive spectrum disorders (OCSDs) has become so influential that there are proposals to introduce it into new diagnostic classificatory systems. The aim of this paper was to assess whether rates of comorbidity and family history of OCSDs in patients with obsessive-compulsive disorder (OCD) supported this concept. Comorbidity and family history were assessed in a group of participants with a primary diagnosis of OCD, using structured clinical interviews. Rates of OCSDs and other anxiety disorders (OADs), excluding OCD, were compared. Of the 77 OCD participants assessed, the most prevalent comorbid conditions were OADs: generalized anxiety disorder (34.6%), specific phobia (26.9%), social phobia (21.8%) and panic disorder (19.2%). The proposed OCSDs were less frequently comorbid: tic disorder (12.8%), trichotillomania (5.1%), hypochondriasis (3.8%) and body dysmorphic disorder (BDD) (3.8%). Similar trends were observed for a family history of these disorders. No participant reported a family history of an OCSD without a family history of an OAD. Although the concept of OCSDs has invigorated thinking in this complex diagnostic field, these results support the current association of OCD with OADs rather than with OCSDs.

Effectiveness and tolerability of second-line treatment with vildagliptin versus other oral drugs for type 2 diabetes in a real-world setting in the Middle East: results from the EDGE study

PubMed Central

Saab, Charles; Al-Saber, Feryal A; Haddad, Jihad; Jallo, Mahir Khalil; Steitieh, Habib; Bader, Giovanni; Ibrahim, Mohamed

2015-01-01

Background Type 2 diabetes mellitus (T2DM) is a chronic progressive disease that requires treatment intensification with antihyperglycemic agents due to progressive deterioration of β-cell function. A large observational study of 45,868 patients with T2DM across 27 countries (EDGE) assessed the effectiveness and safety of vildagliptin as add-on to other oral antidiabetic drugs (OADs) versus other comparator OAD combinations. Here, we present results from the Middle East countries (Bahrain, Jordan, Kuwait, Lebanon, Oman, Palestine, and the United Arab Emirates). Methods Patients inadequately controlled with OAD monotherapy were eligible after the add-on treatment was chosen by the physician based on clinical judgment and patient need. Patients were assigned to either vildagliptin or comparator OADs (sulfonylureas, thiazolidinediones, glinides, α-glucosidase inhibitors, or metformin, except incretin-based therapies) based on the add-on therapy. The primary endpoint was the proportion of patients achieving a glycated hemoglobin (HbA1c) reduction of >0.3% without peripheral edema, hypoglycemia, discontinuation due to a gastrointestinal event, or weight gain ≥5%. One of the secondary endpoints was the proportion of patients achieving HbA1c <7% without hypoglycemia or weight gain. Change in HbA1c from baseline to study endpoint and safety were also assessed. Results Of the 4,780 patients enrolled in the Middle East, 2,513 received vildagliptin and 2,267 received other OADs. Overall, the mean (± standard deviation) age at baseline was 52.1±10.2 years, mean HbA1c was 8.5%±1.3%, and mean T2DM duration was 4.2±4.0 years. The proportion of patients achieving the primary (76.1% versus 61.6%, P<0.0001) and secondary (54.8% versus 29.9%, P<0.0001) endpoints was higher with vildagliptin than with the comparator OADs. The unadjusted odds ratios for the primary and secondary endpoints were 1.98 (95% confidence interval 1.75–2.25) and 2.8 (95% confidence interval 2.5–3.2), respectively, in favor of vildagliptin. Vildagliptin achieved a numerically greater reduction in HbA1c (1.7%) from baseline versus comparator OADs (1.4%). The overall incidence of adverse events was comparable between studied cohorts. Conclusion In real life, treatment with vildagliptin was associated with a higher proportion of patients with T2DM achieving better glycemic control without tolerability issues in the Middle East. PMID:25750538

Effectiveness and tolerability of second-line treatment with vildagliptin versus other oral drugs for type 2 diabetes in a real-world setting in the Middle East: results from the EDGE study.

PubMed

Saab, Charles; Al-Saber, Feryal A; Haddad, Jihad; Jallo, Mahir Khalil; Steitieh, Habib; Bader, Giovanni; Ibrahim, Mohamed

2015-01-01

Type 2 diabetes mellitus (T2DM) is a chronic progressive disease that requires treatment intensification with antihyperglycemic agents due to progressive deterioration of β-cell function. A large observational study of 45,868 patients with T2DM across 27 countries (EDGE) assessed the effectiveness and safety of vildagliptin as add-on to other oral antidiabetic drugs (OADs) versus other comparator OAD combinations. Here, we present results from the Middle East countries (Bahrain, Jordan, Kuwait, Lebanon, Oman, Palestine, and the United Arab Emirates). Patients inadequately controlled with OAD monotherapy were eligible after the add-on treatment was chosen by the physician based on clinical judgment and patient need. Patients were assigned to either vildagliptin or comparator OADs (sulfonylureas, thiazolidinediones, glinides, α-glucosidase inhibitors, or metformin, except incretin-based therapies) based on the add-on therapy. The primary endpoint was the proportion of patients achieving a glycated hemoglobin (HbA1c) reduction of >0.3% without peripheral edema, hypoglycemia, discontinuation due to a gastrointestinal event, or weight gain≥5%. One of the secondary endpoints was the proportion of patients achieving HbA1c<7% without hypoglycemia or weight gain. Change in HbA1c from baseline to study endpoint and safety were also assessed. Of the 4,780 patients enrolled in the Middle East, 2,513 received vildagliptin and 2,267 received other OADs. Overall, the mean (±standard deviation) age at baseline was 52.1±10.2 years, mean HbA1c was 8.5%±1.3%, and mean T2DM duration was 4.2±4.0 years. The proportion of patients achieving the primary (76.1% versus 61.6%, P<0.0001) and secondary (54.8% versus 29.9%, P<0.0001) endpoints was higher with vildagliptin than with the comparator OADs. The unadjusted odds ratios for the primary and secondary endpoints were 1.98 (95% confidence interval 1.75-2.25) and 2.8 (95% confidence interval 2.5-3.2), respectively, in favor of vildagliptin. Vildagliptin achieved a numerically greater reduction in HbA1c (1.7%) from baseline versus comparator OADs (1.4%). The overall incidence of adverse events was comparable between studied cohorts. In real life, treatment with vildagliptin was associated with a higher proportion of patients with T2DM achieving better glycemic control without tolerability issues in the Middle East.

Effects of Tadalafil Once-Daily or On-Demand vs Placebo on Return to Baseline Erectile Function After Bilateral Nerve-Sparing Radical Prostatectomy--Results from a Randomized Controlled Trial (REACTT).

PubMed

Mulhall, John P; Brock, Gerald; Oelke, Matthias; Fode, Mikkel; Probst, Kai A; Henneges, Carsten; d'Anzeo, Gianluca; Rossi, Andrea; Büttner, Hartwig

2016-04-01

The multicenter, randomized, double-blind, double-dummy, placebo-controlled REACTT trial suggested that treatment with tadalafil once daily (OaD) started early after bilateral nerve-sparing radical prostatectomy (nsRP) for prostate cancer may contribute to erectile function (EF)-recovery, which was predefined as achieving an International Index of Erectile Function (IIEF)-EF score ≥22. Here, we report descriptive post-hoc analyses, using the more strict definition for EF-recovery of returning back to the pre-surgery IIEF-EF-level ("back-to-baseline analysis"). REACTT included 422 men <68 years with adenocarcinoma of the prostate and preoperative IIEF-EF ≥22 who underwent nsRP at 50 centers from 9 European countries and Canada. Patients were randomized post-nsRP 1:1:1 to 9-month double-blind treatment (DBT) with tadalafil 5 mg OaD (n = 139), tadalafil 20 mg on-demand (pro-re-nata, PRN; n = 142), or placebo (n = 141), followed by 6-week drug-free washout (DFW) and 3-month open-label tadalafil OaD treatment (OLT). Proportion of patients returning to their preoperative IIEF-EF category (22-25 or ≥26) at the end of DBT, DFW, and OLT. Overall, 92.4% of patients had pre-surgery (baseline) IIEF-EF scores ≥26 (tadalafil OaD 94.2%, PRN 91.6%, placebo 91.5%), 7.4% had IIEF-EF 22-25. At the end of DBT, 22.3% of patients on tadalafil OaD had achieved "back-to-baseline" IIEF-EF, compared with 11.3% on tadalafil PRN and 7.8% on placebo. Of all 58 patients "back-to-baseline" at the end of DBT, only 1 PRN-group patient had started from a baseline IIEF-EF <26. The treatment-group difference at the end of DBT was not maintained after DFW. After 3 months of OLT with tadalafil OaD, the proportion of patients with "back-to-baseline" IIEF-EF had almost doubled in all 3 groups. Changing the definition for EF-recovery from IIEF-EF ≥22 to the more strict definition of "returning back-to-baseline IIEF-EF" had no major impact. Tadalafil OaD started early after nsRP improved drug-assisted EF, but had no effect on unassisted EF following treatment cessation after 9 months. Copyright © 2016 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.

Treatment Intensification in Type 2 Diabetes: A Real-World Study of 2-OAD Regimens, GLP-1 RAs, or Basal Insulin.

PubMed

Blonde, Lawrence; Raccah, Denis; Lew, Elisheva; Meyers, Juliana; Nikonova, Elena; Ajmera, Mayank; Davis, Keith L; Bertolini, Monica; Guerci, Bruno

2018-06-01

Treatment guidelines recommend a stepwise approach to glycemia management in patients with type 2 diabetes (T2D), but this may result in uncontrolled glycated hemoglobin A1c (HbA1c) between steps. This retrospective analysis compared clinical and economic outcomes among patients with uncontrolled T2D initiating two oral antidiabetes drugs (OADs), glucagon-like peptide-1 receptor agonists (GLP-1 RAs), or basal insulin in a real-world setting. Adults with T2D on OAD monotherapy were identified in the MarketScan claims database (2007-2014). Those initiating two OADs (simultaneously or sequentially), GLP-1 RAs, or basal insulin were selected (date of initiation was termed the 'index date'); patients were required to have HbA1c > 7.0% in the 6 months pre-index date. HbA1c was compared from 6 months pre- to 1-year post-index. Annual all-cause healthcare utilization and costs were reported over the 1-year follow-up period. Data for 6054 patients were analyzed (2-OAD, n = 4442; GLP-1 RA, n = 361; basal insulin, n = 1251). Baseline HbA1c was high in all cohorts, but highest in the basal-insulin cohort. Treatment initiation resulted in reductions in HbA1c in all cohorts, which was generally maintained throughout the follow-up period. Average HbA1c reductions from the 6 months pre- to 1 year post-index date were -1.2% for GLP-1 RA, -1.6% for OADs, and -1.8% for basal insulin. HbA1c < 7.0% at 1 year occurred in 32.6%, 47.5%, and 41.1% of patients, respectively. Annual healthcare costs (mean [SD]) were lowest for OAD (US$10,074 [$22,276]) followed by GLP-1 RA (US$14,052 [$23,829]) and basal insulin (US$18,813 [$37,332]). Despite robust HbA1c lowering following treatment initiation, many patients did not achieve HbA1c < 7.0%. Basal insulin, generally prescribed for patients with high baseline HbA1c, was associated with a large reduction in HbA1c and with higher costs. Therapy intensification at an appropriate time could lead to clinical and economic benefits and should be investigated further. Sanofi U.S., Inc.

Treatment intensification using long-acting insulin -predictors of future basal insulin supported oral therapy in the DIVE registry.

PubMed

Danne, Thomas; Bluhmki, Tobias; Seufert, Jochen; Kaltheuner, Matthias; Rathmann, Wolfgang; Beyersmann, Jan; Bramlage, Peter

2015-10-07

In patients with type-2 diabetes receiving oral antidiabetic drugs (OADs), the addition of insulin is frequently required to achieve sufficient control over blood glucose levels. It is, however, difficult to predict if, when and in which patients insulin therapy will be needed. We aimed to identify patient related variables associated with the addition of basal insulin to oral therapy resulting in a basal supported oral therapy (BOT). DIVE (DIabetes Versorgungs-Evaluation) is a prospective, observational, multi-centre diabetes registry established in Germany in 2011. For the present explorative analysis, 31,008 patients with type-2 diabetes prescribed at least one OAD were included. Patients who had previously received insulin and those over 90 years old were excluded. The event of interest was defined as the initiation of BOT during the observational period. Cause-specific Cox proportional hazards models based on a competing risk framework were applied for risk quantification. Multivariable adjusted hazard ratios demonstrated that longer diabetes duration, higher BMI, poorer glycaemic control, documentation of any micro- or macrovascular comorbidity, the presence of concomitant non-antidiabetic pharmacotherapies, and greater numbers of prescribed OADs increased the likelihood of BOT initiation. On the other hand BOT initiation was less likely in patients with older age and female gender. Analysing the likelihood of OAD termination without initiation of BOT provided supportive evidence for the variables predictive of BOT initiation. Analysis of the DIVE registry has resulted in the identification of a number of factors that may be predictive for the initiation of BOT for type-2 diabetes patients initially prescribed one or more OADs. Poor glycaemic control, the presence of vascular comorbidities and concomitant medications, and a greater number of OADs were all detected to increase the risk of a switch to BOT. Female gender and younger age showed protective properties. The close monitoring of patients displaying these characteristics may help to identify individuals who might benefit from early addition of insulin therapy to their oral treatment regimen.

Strain and culture medium optimization for production enhancement of prodiginines from marine-derived Streptomyces sp. GQQ-10

NASA Astrophysics Data System (ADS)

Li, Xueping; Zhang, Guojian; Zhu, Tianjiao; Li, Dehai; Gu, Qianqun

2012-09-01

A mutant (GQQ-M6) of a Sponge-Derived streptomyces sp. GQQ-10 obtained by UV-induced mutation was used for producing prodiginines (PGs). Single factor experiments and orthogonal array design (OAD) methods were employed for medium optimization. In the single factor method, the effects of soluble starch, glucose, soybean flour, yeast extract and sodium acetate on PGs production were investigated individually. In the subsequent OAD experiments, the concentrations of these 5 key nutritional components combined with salinity were further adjusted. The mutant strain GQQ-M6 gave a 2.2-fold higher PGs production than that of the parent strain; OAD experiments offered a PGs yield of 61mg L-1, which was 10 times higher than that of the initial GQQ-10 strain under the original cultivation mode.

New insulin glargine 300 U/ml versus glargine 100 U/ml in Japanese people with type 2 diabetes using basal insulin and oral antihyperglycaemic drugs: glucose control and hypoglycaemia in a randomized controlled trial (EDITION JP 2).

PubMed

Terauchi, Y; Koyama, M; Cheng, X; Takahashi, Y; Riddle, M C; Bolli, G B; Hirose, T

2016-04-01

To compare the efficacy and safety of insulin glargine 300 U/ml (Gla-300) with glargine 100 U/ml (Gla-100) in Japanese people with type 2 diabetes using basal insulin plus oral antihyperglycaemic drug(s) [OAD(s)]. The EDITION JP 2 study (NCT01689142) was a 6-month, multicentre, open-label, phase III study. Participants (n = 241, male 61%, mean diabetes duration 14 years, mean weight 67 kg, mean body mass index 25 kg/m(2), mean glycated haemoglobin (HbA1c) 8.02 %, mean basal insulin dose 0.24 U/kg/day) were randomized to Gla-300 or Gla-100, while continuing OAD(s). Basal insulin was titrated to target fasting self-monitored plasma glucose 4.4-5.6 mmol/l. The primary efficacy endpoint was HbA1c change over 6 months. Safety endpoints included hypoglycaemia and weight change. Gla-300 was non-inferior to Gla-100 for HbA1c reduction [least squares (LS) mean difference 0.10 (95% confidence interval [CI] -0.08, 0.27) %]. The mean HbA1c at month 6 was 7.56 and 7.52 % with Gla-300 and Gla-100, respectively. Nocturnal confirmed (≤3.9 mmol/l) or severe hypoglycaemia risk was 38% lower with Gla-300 versus Gla-100 [relative risk 0.62 (95% CI 0.44, 0.88)]; annualized rates were 55% lower at night [rate ratio 0.45 (95% CI 0.21, 0.96)] and 36% lower at any time [24 h; rate ratio 0.64 (95% CI 0.43, 0.96)]. Severe hypoglycaemia was infrequent. A significant between-treatment difference in weight change favoured Gla-300 [LS mean difference -1.0 (95% CI -1.5, -0.5) kg; p = 0.0003]. Adverse event rates were comparable between groups. Japanese people with type 2 diabetes using basal insulin plus OAD(s) experienced less hypoglycaemia with Gla-300 than with Gla-100, while glycaemic control did not differ. © 2015 The Authors. Diabetes, Obesity and Metabolism published by John Wiley & Sons Ltd.

Impact Injury Caused by Linear Acceleration: Mechanisms, Prevention and Cost

DTIC Science & Technology

1982-04-29

lying in a ventral position to the flexion axis failed by fracture as a result of stress-loading. On the other hand, on the thoracic spinal column...the dorsal ligamentous structures showed signs of stress-1oading and the ventral bony structures showed signs of pressure-1oading. of the most...anguiation upon impact. Are you consider- ing different angulations of the neck-torso to get more cervical injuries which would be expected? AUTHOR’S

Venue of receiving diabetes self-management education and training and its impact on oral diabetic medication adherence.

PubMed

Wu, Jun; Davis-Ajami, Mary Lynn; Noxon, Virginia; Lu, Zhiqiang Kevin

2017-04-01

To determine predictors associated with the diabetes self-management education and training (DSME) venue and its impact on oral antidiabetic (OAD) medication adherence. The Medical Expenditure Panel Survey household component (MEPS-HC) data (2010-2012) identified adults with diabetes prescribed OAD medication(s) who completed a supplemental Diabetes Care Survey (DCS). Based on the DCS responses to questions about the number and type of DSME venue(s), two groups were created: (1) multiple venues (a physician or health professional plus internet and/or group classes) vs (2) single venue (physician or health professional only). The medication possession ratio (MPR) measured medication adherence, with 0.80 the cut-point defining adherent. Logistic regression examined factors associated with the DSME venue and its effect on OAD medication adherence. Of the 2119 respondents, 41.6% received DSME from multiple venues. Age (<65years), education-level (college or higher), high-income, and diet modification were significantly more likely associated with receiving DSME from multiple venues. In single vs multiple venues, medication adherence was suboptimal (mean MPR 0.66 vs 0.64, p=0.245), and venue showed no influence on adherence (OR: 0.92, 95% CI, 0.73-1.16). Sociodemographic characteristics influence where adults with diabetes receive DSME. Adding different DSME venues may not address suboptimal OAD medication adherence. Copyright © 2016 Primary Care Diabetes Europe. Published by Elsevier Ltd. All rights reserved.

Effectiveness of vildagliptin versus other oral antidiabetes drugs as add-on to sulphonylurea monotherapy: Post hoc analysis from the EDGE study.

PubMed

Prasanna Kumar, K M; Phadke, U; Brath, H; Gawai, A; Paldánius, P M; Mathieu, C

2016-12-01

In this post hoc analysis of the EDGE study, we assessed the effectiveness and safety of vildagliptin versus other oral antidiabetes drugs (OADs) as add-on to first-line sulphonylurea (SU) therapy in patients who did not receive metformin in a real-life setting. The primary endpoint was odds of achieving an HbA1c reduction of >0.3% without tolerability issues. Secondary endpoint was odds of achieving HbA1c <7.0% without hypoglycaemia or weight gain. Changes in HbA1c, body weight; and safety were also assessed. 2936 patients received vildagliptin and 820 received comparator OADs (any α-GI, TZD, glinide) as add-on to first-line SU therapy. Overall, the mean age, disease duration, HbA1c, and BMI at baseline were 57.1 years, 6.3 years, 8.5%, and 27.7kg/m 2 , respectively. The odds ratios for achieving primary and secondary endpoints were 1.6 (95% CI: 1.36, 1.86; p<0.0001) and 1.8 (1.45, 2.21; p<0.0001), respectively, in favour of vildagliptin. The between-treatment differences (vildagliptin vs. comparator OAD) for the mean change in HbA1c and body weight were -0.2±0.04% (p<0.0001) and -0.8±0.16kg (p<0.0001), respectively. Overall, the incidence of adverse events was low (vildagliptin, 7% vs. comparator, 8.2%) in both groups. Similar results were observed in a subset of patients enrolled from India and patients who received TZDs as a comparator OAD. Under real-life settings, vildagliptin as add-on to SU monotherapy showed better glycaemic response without tolerability issues compared with other OADs. Copyright © 2016 Primary Care Diabetes Europe. Published by Elsevier Ltd. All rights reserved.

Cost-effectiveness of exenatide twice daily vs insulin glargine as add-on therapy to oral antidiabetic agents in patients with type 2 diabetes in China.

PubMed

Gu, Shuyan; Wang, Xiaoyong; Qiao, Qing; Gao, Weiguo; Wang, Jian; Dong, Hengjin

2017-12-01

To estimate the long-term cost-effectiveness of exenatide twice daily vs insulin glargine once daily as add-on therapy to oral antidiabetic agents (OADs) for Chinese patients with type 2 diabetes (T2DM). The Cardiff Diabetes Model was used to simulate disease progression and estimate the long-term effects of exenatide twice daily vs insulin glargine once daily. Patient profiles and treatment effects required for the model were obtained from literature reviews (English and Chinese databases) and from a meta-analysis of 8 randomized controlled trials comparing exenatide twice daily with insulin glargine once daily add-on to OADs for T2DM in China. Medical expenditure data were collected from 639 patients with T2DM (aged ≥18 years) with and without complications incurred between January 1, 2014 and December 31, 2015 from claims databases in Shandong, China. Costs (2014 Chinese Yuan [¥]) and benefits were estimated, from the payers' perspective, over 40 years at a discount rate of 3%. A series of sensitivity analyses were performed. Patients on exenatide twice daily + OAD had a lower predicted incidence of most cardiovascular and hypoglycaemic events and lower total costs compared with those on insulin glargine once daily + OAD. A greater number of quality-adjusted life years (QALYs; 1.94) at a cost saving of ¥117 706 gained was associated with exenatide twice daily vs insulin glargine once daily. (i.e. cost saving of ¥60 764/QALY) per patient. In Chinese patients with T2DM inadequately controlled by OADs, exenatide twice daily is a cost-effective add-on therapy alternative to insulin glargine once daily, and may address the problem of an excess of medical needs resulting from weight gain and hypoglycaemia in T2DM treatment. © 2017 John Wiley & Sons Ltd.

The influence of spray properties on intranasal deposition.

PubMed

Foo, Mow Yee; Cheng, Yung-Sung; Su, Wei-Chung; Donovan, Maureen D

2007-01-01

While numerous devices, formulations, and spray characteristics have been shown to influence nasal deposition efficiency, few studies have attempted to identify which of these interacting factors plays the greatest role in nasal spray deposition. The deposition patterns of solutions with a wide range of surface tensions and viscosities were measured using an MRI-derived nasal cavity replica. The resulting spray plumes had angles between 29 degrees and 80 degrees and contained droplet sizes (D(v50)) from 37-157 microm. Each formulation contained rhodamine 590 as a fluorescent marker for detection. Administration angles of 30 degrees , 40 degrees , or 50 degrees above horizontal were tested to investigate the role of user technique on nasal deposition. The amount of spray deposited within specific regions of the nasal cavity was determined by disassembling the replica and measuring the amount of rhodamine retained in each section. Most of the spray droplets were deposited onto the anterior region of the model, but sprays with small plume angles were capable of reaching the turbinate region with deposition efficiencies approaching 90%. Minimal dependence on droplet size, viscosity, or device was observed. Changes in inspiratory flow rate (0-60 L/min) had no significant effect on turbinate deposition efficiency. Both plume angle and administration angle were found to be important factors in determining deposition efficiency. For administration angles of 40 degrees or 50 degrees , maximal turbinate deposition efficiency (30-50%) occurred with plume angles of 55-65 degrees , whereas a 30 degrees administration angle gave an approximately 75% deposition efficiency for similar plume angles. Deposition efficiencies of approximately 90% could be achieved with plume angles <30 degrees using 30 degrees administration angles. Both the plume angle and administration angle are critical factors in determining deposition efficiency, while many other spray parameters, including particle size, have relatively minor influences on deposition within the nasal cavity.

Modeling the economic impact of medication adherence in type 2 diabetes: a theoretical approach.

PubMed

Cobden, David S; Niessen, Louis W; Rutten, Frans Fh; Redekop, W Ken

2010-09-07

While strong correlations exist between medication adherence and health economic outcomes in type 2 diabetes, current economic analyses do not adequately consider them. We propose a new approach to incorporate adherence in cost-effectiveness analysis. We describe a theoretical approach to incorporating the effect of adherence when estimating the long-term costs and effectiveness of an antidiabetic medication. This approach was applied in a Markov model which includes common diabetic health states. We compared two treatments using hypothetical patient cohorts: injectable insulin (IDM) and oral (OAD) medications. Two analyses were performed, one which ignored adherence (analysis 1) and one which incorporated it (analysis 2). Results from the two analyses were then compared to explore the extent to which adherence may impact incremental cost-effectiveness ratios. In both analyses, IDM was more costly and more effective than OAD. When adherence was ignored, IDM generated an incremental cost-effectiveness of $12,097 per quality-adjusted life-year (QALY) gained versus OAD. Incorporation of adherence resulted in a slightly higher ratio ($16,241/QALY). This increase was primarily due to better adherence with OAD than with IDM, and the higher direct medical costs for IDM. Incorporating medication adherence into economic analyses can meaningfully influence the estimated cost-effectiveness of type 2 diabetes treatments, and should therefore be considered in health care decision-making. Future work on the impact of adherence on health economic outcomes, and validation of different approaches to modeling adherence, is warranted.

Pharmacogenetic studies update in type 2 diabetes mellitus

PubMed Central

Singh, Shalini; Usman, Kauser; Banerjee, Monisha

2016-01-01

Type 2 diabetes mellitus (T2DM) is a silent progressive polygenic metabolic disorder resulting from ineffective insulin cascading in the body. World-wide, about 415 million people are suffering from T2DM with a projected rise to 642 million in 2040. T2DM is treated with several classes of oral antidiabetic drugs (OADs) viz. biguanides, sulfonylureas, thiazolidinediones, meglitinides, etc. Treatment strategies for T2DM are to minimize long-term micro and macro vascular complications by achieving an optimized glycemic control. Genetic variations in the human genome not only disclose the risk of T2DM development but also predict the personalized response to drug therapy. Inter-individual variability in response to OADs is due to polymorphisms in genes encoding drug receptors, transporters, and metabolizing enzymes for example, genetic variants in solute carrier transporters (SLC22A1, SLC22A2, SLC22A3, SLC47A1 and SLC47A2) are actively involved in glycemic/HbA1c management of metformin. In addition, CYP gene encoding Cytochrome P450 enzymes also play a crucial role with respect to metabolism of drugs. Pharmacogenetic studies provide insights on the relationship between individual genetic variants and variable therapeutic outcomes of various OADs. Clinical utility of pharmacogenetic study is to predict the therapeutic dose of various OADs on individual basis. Pharmacogenetics therefore, is a step towards personalized medicine which will greatly improve the efficacy of diabetes treatment. PMID:27555891

Factors Influencing the Prescribing Preferences of Physicians for Drug-Naive Patients with Type 2 Diabetes Mellitus in the Real-World Setting in Japan: Insight from a Web Survey.

PubMed

Murayama, Hiroki; Imai, Kota; Odawara, Masato

2018-06-01

The Japanese guidelines for type 2 diabetes mellitus (T2DM) emphasize individualization of treatment based on patient need and encourage physicians to select an appropriate oral antidiabetes drug (OAD). However, limited evidence is available on the factors influencing the selection by physicians (diabetes specialists and nonspecialists) of the first-line OAD to treat drug-naive patients with T2DM. A survey was designed to explore the treatment factors and patient characteristics that influence physicians when they choose an initial OAD to prescribe to a drug-naive patient with T2DM in a real-world setting in Japan. The 25-min web-based online survey consisted of simple and focused multiple-choice questions, and was circulated to physicians across eight selected regions in Japan. The primary endpoints were the proportions of physicians who considered particular treatment factors and patient characteristics when selecting the appropriate treatment for drug-naive T2DM patients. A total of 491 physicians participated in the survey. Dipeptidyl peptidase-4 inhibitors (DPP-4is) were the most-preferred first-line OADs, followed by metformin, of both specialists (69% vs. 60%) and nonspecialists (73% vs. 47%). The most influential factors when a DPP-4i was selected were found to be glycated hemoglobin (HbA1c), postprandial glucose (PPG)-lowering effect, and a low risk of hypoglycemia, which were considered by > 80% of physicians, whereas the key factors when metformin was selected were improvement in insulin resistance, low cost, low risk of hypoglycemia, and PPG- and HbA1c-lowering effects, which were considered by > 85% of physicians. Regression analysis revealed that the dominant reason for choosing DPP-4is over metformin was their ease of use in patients with renal impairment, whereas the dominant reasons for choosing metformin over DPP-4is were improvement in insulin resistance and low cost. The key patient characteristics driving the choice of DPP-4is or metformin as the first-line OAD by physicians were similar to those that influenced the treatment intensification decision (DPP-4is: PPG and renal function; metformin: age, BMI, insulin resistance, and renal function). In Japan, DPP-4is are the preferred first-line OADs, followed by metformin. The key treatment factors and patient characteristics considered when selecting DPP-4is or metformin are similar for both specialists and nonspecialists. These results may prompt further discussion of the differences in T2DM treatment between Japan and other counties. Novartis.

Probability of Achieving Glycemic Control with Basal Insulin in Patients with Type 2 Diabetes in Real-World Practice in the USA.

PubMed

Blonde, Lawrence; Meneghini, Luigi; Peng, Xuejun Victor; Boss, Anders; Rhee, Kyu; Shaunik, Alka; Kumar, Supriya; Balodi, Sidhartha; Brulle-Wohlhueter, Claire; McCrimmon, Rory J

2018-06-01

Basal insulin (BI) plays an important role in treating type 2 diabetes (T2D), especially when oral antidiabetic (OAD) medications are insufficient for glycemic control. We conducted a retrospective, observational study using electronic medical records (EMR) data from the IBM ® Explorys database to evaluate the probability of achieving glycemic control over 24 months after BI initiation in patients with T2D in the USA. A cohort of 6597 patients with T2D who started BI following OAD(s) and had at least one valid glycated hemoglobin (HbA1c) result recorded both within 90 days before and 720 days after BI initiation were selected. We estimated the changes from baseline in HbA1c every 6 months, the quarterly conditional probabilities of reaching HbA1c < 7% if a patient had not achieved glycemic control prior to each quarter (Q), and the cumulative probability of reaching glycemic control over 24 months. Our cohort was representative of patients with T2D who initiated BI from OADs in the USA. The average HbA1c was 9.1% at BI initiation, and decreased robustly (1.5%) in the first 6 months after initiation with no further reductions thereafter. The conditional probability of reaching glycemic control decreased rapidly in the first year (26.6% in Q2; 17.6% in Q3; 8.6% in Q4), and then remained low (≤ 6.1%) for each quarter in the second year. Cumulatively, about 38% of patients reached HbA1c < 7% in the first year; only approximately 8% more did so in the second year. Our study of real-world data from a large US EMR database suggested that among patients with T2D who initiated BI after OADs, the likelihood of reaching glycemic control diminished over time, and remained low from 12 months onwards. Additional treatment options should be considered if patients do not reach glycemic control within 12 months of BI initiation. Sanofi Corporation.

Astronomy for a Better World: IAU OAD Task Force-1 Programs for Advancing Astronomy Education and Research in Universities in Developing Countries

NASA Astrophysics Data System (ADS)

Guinan, Edward; Kolenberg, Katrien

2015-03-01

We discuss the IAU Commission 46 and Office for Astronomy Development (OAD) programs that support advancing Astronomy education and research primarily in universities in developing countries. The bulk of these operational activities will be coordinated through the OAD's newly installed Task Force 1. We outline current (and future) IAU/OAD Task Force-1 programs that promote the development of University-level Astronomy at both undergraduate and graduate levels. Among current programs discussed are the past and future expanded activities of the International School for Young Astronomers (ISYA) and the Teaching Astronomy for Development (TAD) programs. The primary role of the ISYA program is the organization of a three week School for students for typically M.Sc. and Ph.D students. The ISYA is a very successful program that will now be offered more frequently through the generous support of the Kavli Foundation. The IAU/TAD program provides aid and resources for the development of teaching, education and research in Astronomy. The TAD program is dedicated to assist countries that have little or no astronomical activity, but that wish to develop or enhance Astronomy education. Over the last ten years, the ISYA and TAD programs have supported programs in Africa, Asia, Central America and the Caribbean, the Middle East, South East and West Asia, and South America. Several examples are given. Several new programs being considered by OAD Task Force-1 are also discussed. Other possible programs being considered are the introduction of modular Astronomy courses into the university curricula (or improve present courses) as well as providing access to ``remote learning`` courses and Virtual Astronomy labs in developing countries. Another possible new program would support visits of astronomers from technically advanced countries to spend their sabbatical leaves teaching and advising University Astronomy programs in developing countries. Suggestions for new Task Force -1 programs are also welcomed. Useful information about the participation of IAU members and volunteers in these programs will be discussed and practical information will be provided.

Childhood separation anxiety disorder and adult onset panic attacks share a common genetic diathesis.

PubMed

Roberson-Nay, Roxann; Eaves, Lindon J; Hettema, John M; Kendler, Kenneth S; Silberg, Judy L

2012-04-01

Childhood separation anxiety disorder (SAD) is hypothesized to share etiologic roots with panic disorder. The aim of this study was to estimate the genetic and environmental sources of covariance between childhood SAD and adult onset panic attacks (AOPA), with the primary goal to determine whether these two phenotypes share a common genetic diathesis. Participants included parents and their monozygotic or dizygotic twins (n = 1,437 twin pairs) participating in the Virginia Twin Study of Adolescent Behavioral Development and those twins who later completed the Young Adult Follow-Up (YAFU). The Child and Adolescent Psychiatric Assessment was completed at three waves during childhood/adolescence followed by the Structured Clinical Interview for DSM-III-R at the YAFU. Two separate, bivariate Cholesky models were fit to childhood diagnoses of SAD and overanxious disorder (OAD), respectively, and their relation with AOPA; a trivariate Cholesky model also examined the collective influence of childhood SAD and OAD on AOPA. In the best-fitting bivariate model, the covariation between SAD and AOPA was accounted for by genetic and unique environmental factors only, with the genetic factor associated with childhood SAD explaining significant variance in AOPA. Environmental risk factors were not significantly shared between SAD and AOPA. By contrast, the genetic factor associated with childhood OAD did not contribute significantly to AOPA. Results of the trivariate Cholesky reaffirmed outcomes of bivariate models. These data indicate that childhood SAD and AOPA share a common genetic diathesis that is not observed for childhood OAD, strongly supporting the hypothesis of a specific genetic etiologic link between the two phenotypes. © 2012 Wiley Periodicals, Inc.

Oblique angle deposition-induced anisotropy in Co2FeAl films

NASA Astrophysics Data System (ADS)

Zhou, W.; Brock, J.; Khan, M.; Eid, K. F.

2018-06-01

A series of Co2FeAl Heusler alloy films, fabricated on Si/SiO2 substrates by magnetron sputtering-oblique angle deposition technique, have been investigated by magnetization and transport measurements. The morphology and magnetic anisotropy of the films strongly depended on the deposition angle. While the film deposited at zero degree (i.e. normal incidence) did not show any anisotropy, the films deposited at higher angles showed unusually strong in-plane anisotropy that increased with deposition angle. The enhanced anisotropy was well-reflected in the direction-dependent magnetization and the coercivity of the films that increased dramatically from 30 Oe to 490 Oe. In a similar vein, the electrical resistivity of the films also increased drastically, especially for deposition angles larger than 60°. These anisotropic effects and their relation to the morphology of the films are discussed.

Prescription Factors Associated with Medication Non-adherence in Japan Assessed from Leftover Drugs in the SETSUYAKU-BAG Campaign: Focus on Oral Antidiabetic Drugs.

PubMed

Koyanagi, Kaori; Kubota, Toshio; Kobayashi, Daisuke; Kihara, Taro; Yoshida, Takeo; Miisho, Takamasa; Miura, Tomoko; Sakamoto, Yoshiko; Takaki, Junichi; Seo, Takashi; Shimazoe, Takao

2016-01-01

Medication adherence has an important influence on health outcomes in patients with chronic diseases. However, few studies have been performed in Japan to determine factors related to medication non-adherence. The aim of this study was to identify prescription factors related to medication non-adherence by investigating patient characteristics, all prescriptions, and prescriptions for oral antidiabetic drugs (OADs). A retrospective cross-sectional survey of prescription data about implementation of dosing regimen was performed at community pharmacies engaged in appropriate use of leftover drugs. We evaluated the amount of drugs originally prescribed and the reduced amount after use of leftover drugs, and then calculated prescription reduction ratio (PRR). We analyzed prescription factors contributing to non-adherence based on the PRR. Prescription information for 1207 patients was reviewed, revealing that patients were non-adherent to 58% of prescriptions. Lack of a drug copayment, fewer concurrent drugs, and drugs not in single-dose packaging were associated with non-adherence. Among the 1207 patients, 234 prescriptions for diabetes and 452 OAD formulations were included. Forty-seven percent of prescriptions and 29% of the formulations were non-adherent. A higher dosing frequency and preprandial administration were associated with non-adherence. Among the OADs, adherence was lower for α-glucosidase inhibitors and biguanides than for sulfonylureas. Several factors related to patient characteristics, general drug prescriptions, and OAD prescriptions were associated with non-adherence. Further consideration will be needed to improve adherence to medication in Japan. Health care providers should perform more careful monitoring of adherence in patients with the factors identified by this study.

Pancreatic cancer therapy with combined mesothelin-redirected chimeric antigen receptor T cells and cytokine-armed oncolytic adenoviruses

PubMed Central

Watanabe, Keisuke; Luo, Yanping; Da, Tong; Scholler, John; Keith, Brian; Young, Regina M.; Sorsa, Suvi; Siurala, Mikko; Havunen, Riikka; Tähtinen, Siri; Hemminki, Akseli

2018-01-01

Pancreatic ductal adenocarcinoma (PDA) is characterized by its highly immunosuppressive tumor microenvironment (TME) that limits T cell infiltration and induces T cell hypofunction. Mesothelin-redirected chimeric antigen receptor T cell (meso-CAR T cell) therapy has shown some efficacy in clinical trials but antitumor efficacy remains modest. We hypothesized that combined meso-CAR T cells with an oncolytic adenovirus expressing TNF-α and IL-2 (Ad5/3-E2F-D24-TNFa-IRES-IL2, or OAd-TNFa-IL2) would improve efficacy. OAd-TNFa-IL2 enhanced the antitumor efficacy of meso-CAR T cells in human-PDA-xenograft immunodeficient mice and efficacy was associated with robustly increased tumor-infiltrating lymphocytes (TILs), enhanced and prolonged T cell function. Mice treated with parental OAd combined with meso-CAR T developed tumor metastasis to the lungs even if primary tumors were controlled. However, no mice treated with combined OAd-TNFa-IL2 and meso-CAR T died of tumor metastasis. We also evaluated this approach in a syngeneic mouse tumor model by combining adenovirus expressing murine TNF-α and IL-2 (Ad-mTNFa-mIL2) and mouse CAR T cells. This approach induced significant tumor regression in mice engrafted with highly aggressive and immunosuppressive PDA tumors. Ad-mTNFa-mIL2 increased both CAR T cell and host T cell infiltration to the tumor and altered host tumor immune status with M1 polarization of macrophages and increased dendritic cell maturation. These findings indicate that combining cytokine-armed oncolytic adenovirus to enhance the efficacy of CAR T cell therapy is a promising approach to overcome the immunosuppressive TME for the treatment of PDA. PMID:29618658

Impact of polyunsaturated vegetable oils on adiponectin levels, glycaemia and blood lipids in individuals with type 2 diabetes: a randomised, double-blind intervention study.

PubMed

Müllner, E; Plasser, E; Brath, H; Waldschütz, W; Forster, E; Kundi, M; Wagner, K-H

2014-10-01

Low adiponectin levels are discussed as risk factor for cardiovascular events. This is of special importance in individuals with type 2 diabetes (T2DM) because they are at higher risk for cardiovascular diseases. The present study aimed to investigate the effect of two plant oils rich in polyunsaturated fatty acids (PUFA), with different content of omega-3 fatty acids, on adiponectin levels, glucose and lipid metabolism in T2DM individuals treated either with insulin or oral anti-diabetics (OAD). Ninety-two subjects with T2DM [34 treated with insulin (T2DM-Ins) and 58 treated with OAD (T2DM-OAD)] participated in this randomised, double-blind, parallel intervention study. Individuals received either 9 g of nut oil (n-3:n-6 ratio: 1.3 : 6.1) or mixed oil (n-3:n-6 ratio: 0.6 : 5.7) per day for 10 weeks. The fatty acid profile, tocopherol, adiponectin levels and parameters regarding glucose and lipid metabolism were assessed at baseline, during and after the intervention. Compliance was confirmed by significant increases in γ-tocopherol and PUFA in both oil groups. An increase in adiponectin levels in T2DM-Ins participants (+6.84% in nut oil and +4.47% in mixed oil group after 10 weeks compared to baseline) was observed, albeit not significantly different from T2DM-OAD individuals (P = 0.051). Lipid and glucose metabolism were not affected by the intervention. The present study provides evidence that a small and easy change in dietary behaviour towards better fat quality moderately increases adiponectin levels in T2DM-Ins subjects, independently of the administered plant oil. © 2013 The British Dietetic Association Ltd.

Psychosocial outcomes after initial treatment of erectile dysfunction with tadalafil once daily, tadalafil on demand or sildenafil citrate on demand: results from a randomized, open-label study.

PubMed

Hatzimouratidis, K; Buvat, J; Büttner, H; Vendeira, P A S; Moncada, I; Boehmer, M; Henneges, C; Boess, F G

2014-01-01

Initiation of ED treatment with a particular PDE5I may influence treatment-adherence and other outcomes. In this multicenter, open-label study, men with ED, naïve to PDE5I, were randomized to tadalafil 5 mg once-a-day (OaD; N=257), 10 mg on demand (PRN; N = 252) or sildenafil-citrate (sildenafil) 50 mg PRN (N = 261) for 8 weeks (dose adjustments allowed), followed by 16 weeks of pragmatic treatment (switching between PDE5I allowed). Primary outcomes (treatment-adherence) were reported previously. Here, we report effects on: Psychological and Interpersonal Relationship Scales, Self-Esteem and Relationship (SEAR) questionnaire, ED Inventory of Treatment Satisfaction (EDITS), International Index of Erectile Function (IIEF), Sexual Encounter Profile (SEP) and Global Assessment Questions (GAQ). Mixed-model for repeated measures and analysis of covariance were used to analyze changes from baseline; GAQ-responses were evaluated by logistic regression. Analyses were adjusted for treatment, country, ED-severity, baseline and baseline-by-treatment interaction. Patients randomized to tadalafil OaD or PRN reported greater improvement (least-square mean (s.e.) change) in Sexual Self-Confidence (OaD +0.90 (0.048), PRN +0.93 (0.050), vs +0.73 (0.049); P=0.006 and P=0.001) and Spontaneity (OaD +0.11 (0.035), PRN +0.13 (0.035), vs +0.02 (0.035); P = 0.044 and P = 0.010) compared with sildenafil. Improvements in GAQ and SEP responses, IIEF-EF, orgasmic function, sexual desire, overall satisfaction domains, SEAR and EDITS scores did not differ significantly between treatment groups.

Molecular interactions of plant oil components with stratum corneum lipids correlate with clinical measures of skin barrier function

PubMed Central

Mack Correa, Mary Catherine; Mao, Guangru; Saad, Peter; Flach, Carol R; Mendelsohn, Richard; Walters, Russel M

2014-01-01

Plant-derived oils consisting of triglycerides and small amounts of free fatty acids (FFAs) are commonly used in skincare regimens. FFAs are known to disrupt skin barrier function. The objective of this study was to mechanistically study the effects of FFAs, triglycerides and their mixtures on skin barrier function. The effects of oleic acid (OA), glyceryl trioleate (GT) and OA/GT mixtures on skin barrier were assessed in vivo through measurement of transepidermal water loss (TEWL) and fluorescein dye penetration before and after a single application. OA's effects on stratum corneum (SC) lipid order in vivo were measured with infrared spectroscopy through application of perdeuterated OA (OA-d34). Studies of the interaction of OA and GT with skin lipids included imaging the distribution of OA-d34 and GT ex vivo with IR microspectroscopy and thermodynamic analysis of mixtures in aqueous monolayers. The oil mixtures increased both TEWL and fluorescein penetration 24 h after a single application in an OA dose-dependent manner, with the highest increase from treatment with pure OA. OA-d34 penetrated into skin and disordered SC lipids. Furthermore, the ex vivo IR imaging studies showed that OA-d34 permeated to the dermal/epidermal junction while GT remained in the SC. The monolayer experiments showed preferential interspecies interactions between OA and SC lipids, while the mixing between GT and SC lipids was not thermodynamically preferred. The FFA component of plant oils may disrupt skin barrier function. The affinity between plant oil components and SC lipids likely determines the extent of their penetration and clinically measurable effects on skin barrier functions. PMID:24372651

Presence of sarcopenia in asthma-COPD overlap syndrome may be a risk factor for decreased bone-mineral density, unlike asthma: Korean National Health and Nutrition Examination Survey (KNHANES) IV and V (2008-2011).

PubMed

Lee, Dong-Won; Jin, Hyun-Jung; Shin, Kyeong-Cheol; Chung, Jin-Hong; Lee, Hyoung-Woo; Lee, Kwan-Ho

2017-01-01

Sarcopenia and decreased bone-mineral density (BMD) are common in elderly people, and are major comorbidities of obstructive airway disease (OAD). However, the relationship between sarcopenia and BMD in each OAD phenotype, especially asthma-COPD overlap syndrome (ACOS), is not yet clear. We aimed to evaluate differences in BMD according to the presence of sarcopenia in each OAD phenotype. Among the research subjects in KNHANES IV and V (2008-2011), 5,562 were ≥50 years old and underwent qualified spirometry and dual-energy X-ray absorptiometry. A total of 947 subjects were included in the study: 89 had asthma, 748 COPD, and 110 ACOS. In the COPD and ACOS phenotypes, T-scores were lower in the sarcopenia group than the nonsarcopenia group. Prevalence rates of osteopenia and osteoporosis were higher in the sarcopenia group than the nonsarcopenia group. ( P <0.001 and P =0.017, respectively). The sarcopenia group had higher risks of developing osteopenia, osteoporosis, and low BMD than the nonsarcopenia group in the ACOS phenotype (OR 6.620, 95% CI 1.129-38.828 [ P =0.036], OR 9.611, 95% CI 1.133-81.544 [ P =0.038], and OR 6.935, 95% CI 1.194-40.272 [ P =0.031], respectively). However, in the asthma phenotype, the sarcopenia group showed no increased risk compared with the nonsarcopenia group. In the ACOS phenotype, individuals with sarcopenia had a higher prevalence rate and higher risks of osteopenia and osteoporosis than those without sarcopenia among all OAD phenotypes.

Residual stress in obliquely deposited MgF2 thin films.

PubMed

Jaing, Cheng-Chung; Liu, Ming-Chung; Lee, Cheng-Chung; Cho, Wen-Hao; Shen, Wei-Ting; Tang, Chien-Jen; Liao, Bo-Huei

2008-05-01

MgF(2) films with a columnar microstructure are obliquely deposited on glass substrates by resistive heating evaporation. The columnar angles of the films increases with the deposition angle. Anisotropic stress does not develop in the films with tilted columns. The residual stresses in the films depend on the deposition and columnar angles in a columnar microstructure.

The TJO-OAdM robotic observatory: OpenROCS and dome control

NASA Astrophysics Data System (ADS)

Colomé, Josep; Francisco, Xavier; Ribas, Ignasi; Casteels, Kevin; Martín, Jonatan

2010-07-01

The Telescope Joan Oró at the Montsec Astronomical Observatory (TJO - OAdM) is a small-class observatory working in completely unattended control. There are key problems to solve when a robotic control is envisaged, both on hardware and software issues. We present the OpenROCS (ROCS stands for Robotic Observatory Control System), an open source platform developed for the robotic control of the TJO - OAdM and similar astronomical observatories. It is a complex software architecture, composed of several applications for hardware control, event handling, environment monitoring, target scheduling, image reduction pipeline, etc. The code is developed in Java, C++, Python and Perl. The software infrastructure used is based on the Internet Communications Engine (Ice), an object-oriented middleware that provides object-oriented remote procedure call, grid computing, and publish/subscribe functionality. We also describe the subsystem in charge of the dome control: several hardware and software elements developed to specially protect the system at this identified single point of failure. It integrates a redundant control and a rain detector signal for alarm triggering and it responds autonomously in case communication with any of the control elements is lost (watchdog functionality). The self-developed control software suite (OpenROCS) and dome control system have proven to be highly reliable.

“Astronomy for a Better World”: IAU/OAD Task Force One Activities to Develop Astronomy Education and Research at Universities in the Developing World

NASA Astrophysics Data System (ADS)

Guinan, Edward Francis; Kolenberg, Katrien

2015-08-01

The Task Force (1) on Astronomy for Universities & Research (TF-1) was established in 2012 as part of the IAU Office of Astronomy for Development (OAD). This Task Force drives activities related to astronomy education and research at universities mainly in the developing world. Astronomy is used to stimulate research and education in STEM fields and to develop and promote astronomy in regions of the world where there is little or no astronomy. There is also potential for developing research in the historical and cultural aspects of astronomy which may prove important for stimulating an interest in the subject in communities where there is yet no established interest in the science.Since the establishment of the OAD, over 25 TF-1 programs have been funded (or partially funded) to support a wide variety of interesting and innovative astronomy programs in Africa, Asia, South-East Asia, Middle-East, and in South & Central America. Nearly every aspect of development has been supported. These programs include supporting: regional astronomy training schools, specialized workshops, research visits, university twinning programs, distance learning projects, university astronomy curriculum development, as well as small telescope and equipment grants. In addition, a large new program - Astrolab - was introduced (by J-P De Greve and Michele Gerbaldi) to bring starlight” into the class room. In the Astrolab program students carry out and reduce CCD photometry secured by them using remotely controlled telescopes. Results from pilot programs will be discussed.OAD TF-1 programs will be discussed along with future plans for improving and expanding these programs to bring astronomy education and research to a greater number of people and indeed to use Astronomy for a Better World. Information and advice will also be provided about applying for support in the future.

Evaluation of patients with type 2 diabetes mellitus receiving treatment during the pre-diabetes period: Is early treatment associated with improved outcomes?

PubMed

Chaudhari, Paresh; Vallarino, Carlos; Law, Ernest H; Seifeldin, Raafat

2016-12-01

This study evaluates the association of pretreatment with oral antidiabetics (OADs) on clinical outcomes and health resource utilization among commercially insured type II diabetes mellitus (T2DM) patients in the United States. Using administrative data (Truven MarketScan® Research Databases), patients diagnosed with T2DM between 2007 and 2014 with ⩾6months continuous enrolment pre- and post-diagnosis were evaluated. Pretreatment was defined as OAD use at least 3months prior to T2DM diagnosis. Time-to-insulin initiation and healthcare costs were compared by OAD pretreatment status. Of the 866,605 patients studied, 241,856 (27.9%) were pretreated prior to T2DM diagnosis. Mean follow-up was 2.9years for pretreatment and 3.1years for those without pretreatment. Monthly diabetes-related pharmacy costs were significantly higher among pretreated patients ($66 versus $36, p<0.0001), as were overall monthly pharmacy costs ($255 versus $198, p<0.0001). Pretreated patients had lower mean monthly costs, both total ($625 versus $671, p<0.0001) and diabetes-related ($207 versus $214, p=0.0012). After multivariable adjustment, mean monthly diabetes-related total healthcare costs were higher among pretreated patients (+$60) but total all-cause monthly healthcare costs were significantly lower (-$354) (both p<0.05). Pretreatment was associated with a lower insulin initiation probability for 2years, after which probability was similar; the adjusted hazard ratio for pretreatment in a time-to-insulin model was 0.96 (95% CI, 0.94-0.97). Pretreatment with OADs is associated with a modest delay in initiating insulin therapy and lower total healthcare costs. The clinical and pharmacoeconomic benefits of pretreatment should be elucidated in a prospective study. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Functional mechanism of lung mosaic CT attenuation: assessment with deep-inspiration breath-hold perfusion SPECT-CT fusion imaging and non-breath-hold Technegas SPECT.

PubMed

Suga, K; Yasuhiko, K; Iwanaga, H; Tokuda, O; Matsunaga, N

2009-01-01

The functional mechanism of lung mosaic computed tomography attenuation (MCA) in pulmonary vascular disease (PVD) and obstructive airway disease (OAD) has not yet been fully clarified. To clarify the mechanism of MCA in these diseases by assessing the relationship between regional lung function and CT attenuation change at MCA sites with the use of automated deep-inspiratory breath-hold (DIBrH) perfusion single-photon emission computed tomography (SPECT)-CT fusion images and non-breath-hold Technegas SPECT. Subjects were 42 PVD patients (31 pulmonary thromboembolism, four primary/two secondary pulmonary hypertension, and five Takayasu arteritis), 12 OAD patients (five acute asthma, four obliterative bronchiolitis, and three bronchiectasis), and 12 normal controls, all of whom had MCA on DIBrH CT. The relationship between regional lung function and CT attenuation change at the lung slices with MCA was assessed using DIBrH perfusion SPECT-CT fusion images and non-breath-hold Technegas SPECT. The severity of perfusion defects with or without MCA was quantified by regions-of-interest analysis. On DIBrH CT and perfusion SPECT, in contrast to no noticeable CT attenuation abnormality and fairly uniform perfusion in controls, 60 MCA and 274 perfusion defects in PVD patients, and 18 MCA and 61 defects in OAD patients were identified, with a total of 77 ventilation defects on Technegas SPECT in all patients. SPECT-CT correlation showed that, throughout the 78 MCA sites of all patients, lung perfusion was persistently decreased at low CT attenuation and preserved at intervening high CT attenuation, while lung ventilation was poorly correlated with CT attenuation change. The radioactivity ratios of reduced perfusion and the intervening preserved perfusion at the 78 perfusion defects with MCA were significantly lower than those at the remaining 257 defects without MCA (P<0.0001). Although further validation is required, our results indicate that heterogeneous pulmonary arterial perfusion may be a dominant mechanism of MCA in PVD and OAD.

Microstructure-related properties of magnesium fluoride films at 193nm by oblique-angle deposition.

PubMed

Guo, Chun; Kong, Mingdong; Lin, Dawei; Liu, Cunding; Li, Bincheng

2013-01-14

Magnesium fluoride (MgF2) films deposited by resistive heating evaporation with oblique-angle deposition have been investigated in details. The optical and micro-structural properties of single-layer MgF2 films were characterized by UV-VIS and FTIR spectrophotometers, scanning electron microscope (SEM), atomic force microscope (AFM), and x-ray diffraction (XRD), respectively. The dependences of the optical and micro-structural parameters of the thin films on the deposition angle were analyzed. It was found that the MgF2 film in a columnar microstructure was negatively inhomogeneous of refractive index and polycrystalline. As the deposition angle increased, the optical loss, extinction coefficient, root-mean-square (rms) roughness, dislocation density and columnar angle of the MgF2 films increased, while the refractive index, packing density and grain size decreased. Furthermore, IR absorption of the MgF2 films depended on the columnar structured growth.

Investigations of the fabrication and the surface-enhanced Raman scattering detection applications for tapered fiber probes prepared with the laser-induced chemical deposition method.

PubMed

Fan, Qunfang; Cao, Jie; Liu, Ye; Yao, Bo; Mao, Qinghe

2013-09-01

The process of depositing nanoparticles onto tapered fiber probes with the laser-induced chemical deposition method (LICDM) and the surface-enhanced Raman scattering (SERS) detection performance of the prepared probes are experimentally investigated in this paper. Our results show that the nanoparticle-deposited tapered fiber probes prepared with the LICDM method depend strongly on the value of the cone angle. For small-angle tapered probes the nanoparticle-deposited areas are only focused at the taper tips, because the taper surfaces are mainly covered by a relatively low-intensity evanescent field. By lengthening the reaction time or increasing the induced power or solution concentration, it is still possible to deposit nanoparticles on small-angle tapers with the light-scattering effect. With 4-aminothiophenol as the testing molecule, it was found that for given preparation conditions, the cone angles for the tapered probes with the highest SERS spectral intensities for different excitation laser powers are almost the same. However, such an optimal cone angle is determined by the combined effects of both the localized surface plasmon resonance strength and the transmission loss generated by the nanoparticles deposited.

Analysis of access to hypertensive and diabetic drugs in the Family Health Strategy, State of Pernambuco, Brazil.

PubMed

Barreto, Maria Nelly Sobreira de Carvalho; Cesse, Eduarda Ângela Pessoa; Lima, Rodrigo Fonseca; Marinho, Michelly Geórgia da Silva; Specht, Yuri da Silva; de Carvalho, Eduardo Maia Freese; Fontbonne, Annick

2015-01-01

To evaluate the access to drugs for hypertension and diabetes and the direct cost of buying them among users of the Family Health Strategy (FHS) in the state of Pernambuco, Brazil. Population-based, cross-sectional study of a systematic random sample of 785 patients with hypertension and 823 patients with diabetes mellitus who were registered in 208 randomly selected FHS teams in 35 municipalities of the state of Pernambuco. The selected municipalities were classified into three levels with probability proportional to municipality size (LS, large-sized; MS, medium-sized; SS, small-sized). To verify differences between the cities, we used the χ2 test. Pharmacological treatment was used by 91.2% patients with hypertension whereas 85.6% patients with diabetes mellitus used oral antidiabetic drugs (OADs), and 15.4% used insulin. The FHS team itself provided antihypertensive medications to 69.0% patients with hypertension, OADs to 75.0% patients with diabetes mellitus, and insulin treatment to 65.4%. The 36.9% patients with hypertension and 29.8% with diabetes mellitus that had to buy all or part of their medications reported median monthly cost of R$ 18.30, R$ 14.00, and R$ 27.61 for antihypertensive drugs, OADs, and insulin, respectively. It is necessary to increase efforts to ensure access to these drugs in the primary health care network.

Improved performance of organic light-emitting diodes with MoO3 interlayer by oblique angle deposition.

PubMed

Liu, S W; Divayana, Y; Sun, X W; Wang, Y; Leck, K S; Demir, H V

2011-02-28

We fabricated and demonstrated improved organic light emitting diodes (OLEDs) in a thin film architecture of indium tin oxide (ITO)/ molybdenum trioxide (MoO3) (20 nm)/N,N'-Di(naphth-2-yl)-N,N'-diphenyl-benzidine (NPB) (50 nm)/ tris-(8-hydroxyquinoline) (Alq3) (70 nm)/Mg:Ag (200 nm) using an oblique angle deposition technique by which MoO3 was deposited at oblique angles (θ) with respect to the surface normal. It was found that, without sacrificing the power efficiency of the device, the device current efficiency and external quantum efficiency were significantly enhanced at an oblique deposition angle of θ=60° for MoO3.

Controlled growth of standing Ag nanorod arrays on bare Si substrate using glancing angle deposition for self-cleaning applications

NASA Astrophysics Data System (ADS)

Singh, Dhruv P.; Singh, J. P.

2014-03-01

A facile approach to manipulate the hydrophobicity of surface by controlled growth of standing Ag nanorod arrays is presented. Instead of following the complicated conventional method of the template-assisted growth, the morphology or particularly average diameter and number density (nanorods cm-2) of nanorods were controlled on bare Si substrate by simply varying the deposition rate during glancing angle deposition. The contact angle measurements showed that the evolution of Ag nanorods reduces the surface energy and makes an increment in the apparent water contact angle compared to the plain Ag thin film. The contact angle was found to increase for the Ag nanorod samples grown at lower deposition rates. Interestingly, the morphology of the nanorod arrays grown at very low deposition rate (1.2 Å sec-1) results in a self-cleaning superhydrophobic surface of contact angle about 157° and a small roll-off angle about 5°. The observed improvement in hydrophobicity with change in the morphology of nanorod arrays is explained as the effect of reduction in solid fraction within the framework of Cassie-Baxter model. These self-cleaning Ag nanorod arrays could have a significant impact in wide range of applications such as anti-icing coatings, sensors and solar panels.

The effect of 7,8-methylenedioxylycoctonine-type diterpenoid alkaloids on the toxicity of methyllycaconitine in mice.

PubMed

Welch, K D; Panter, K E; Gardner, D R; Green, B T; Pfister, J A; Cook, D; Stegelmeier, B L

2008-10-01

Larkspur plants contain numerous norditerpenoid alkaloids, which include the 7,8-methylenedioxylycoctonine (MDL)-type alkaloids and the N-(methylsuccinimido)anthranoyllycoctonine (MSAL)-type alkaloids. The MSAL-type alkaloids are generally much more toxic (typically >20 times). Toxicity of many tall larkspurs, such as Delphinium barbeyi, has been attributed to its large concentration of MSAL-type alkaloids, including methyllycaconitine (MLA). However, the norditerpenoid alkaloids found in the greatest concentrations in most D. barbeyi populations are either deltaline or 14-O-acetyldictyocarpine (14-OAD), both less toxic MDL-type alkaloids. Although the individual toxicities of MLA, 14-OAD, and deltaline have been determined, the impact (additive or antagonistic) that large concentrations of deltaline or 14-OAD in the plant have on the toxicity of MLA is unknown. Consequently, the effect of MDL-type alkaloids on the toxicity of MLA was compared by using median lethal dose (LD(50)) and toxicokinetic profiles of the brainand muscle from mice receiving i.v. administration of these alkaloids, individually or in combination, at ratios of 1:1, 1:5, and 1:25 MLA to MDL-type alkaloids. The LD(50) for MLA alone was 4.4 +/- 0.7 mg/kg of BW, whereas the coadministration of MLA and deltaline at 1:1, 1:5, and 1:25 resulted in an LD(50) of 2.7, 2.5, and 1.9 mg/kg of BW, respectively. Similarly, the coadministration of MLA and 14-OAD at 1:1, 1:5, and 1:25 resulted in an LD(50) of 3.1, 2.2, and 1.5 mg/kg of BW, respectively. Coadministration of mixtures did not result in increased MLA bioavailability or alterations in clearance from the brain and muscle. Consequently, the increased toxicity of the mixtures was not a result of increased MLA bioavailability (based on the maximum concentrations observed) or alterations in MLA clearance from the brain and muscle, because these were unchanged. These results demonstrate that MDL-type alkaloids have an additive effect on MLA toxicity in mice and may also play a role in the overall toxicity of tall larkspur plants in cattle.

Risk of vaginal bleeding and postpartum hemorrhage after use of antidepressants in pregnancy: a study from the Norwegian Mother and Child Cohort Study.

PubMed

Lupattelli, Angela; Spigset, Olav; Koren, Gideon; Nordeng, Hedvig

2014-02-01

This study aimed to examine obstetric bleeding outcomes after exposure during pregnancy to selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs), tricyclic (TCAs), and other antidepressants (OADs).The Norwegian Mother and Child Cohort Study and the Medical Birth Registry of Norway constituted the data source for the present study. We included 57,279 pregnant women, of which 1.02% reported use of antidepressants during pregnancy, mostly SSRIs/SNRIs (0.92%). We categorized exposure according to antidepressant use in pregnancy (SSRIs/SNRIs, n = 527; TCAs/OADs, n = 59; nonexposed, nondepressed, n = 55,411) with inclusion of a disease comparison group (nonexposed, depressed, n = 1282). We used logistic regression to estimate adjusted odds ratio (aOR) and 95% confidence interval (CI) for vaginal bleeding outcomes in pregnancy and postpartum hemorrhage.Compared with nonexposed subjects, first trimester exposure to SSRIs/SNRIs or TCAs/OADs did not confer any increased risk of vaginal bleeding in early pregnancy (aOR, 0.91; 95% CI, 0.72-1.16 and aOR, 0.83; 95% CI, 0.36-1.92, respectively). No increased risk for vaginal bleeding in midpregnancy was observed among users of SSRIs/SNRIs (aOR, 0.81; 95% CI, 0.50-1.31) or TCAs/OADs (aOR, 0.96; 95% CI, 0.26-3.53) in second trimester. Exposure to SSRIs/SNRIs during gestational week 30 to childbirth did not confer any increased risk of postpartum hemorrhage after vaginal (aOR, 0.90; 95% CI, 0.47-1.74) or cesarean (aOR, 1.47; 95% CI, 0.51-4.22) delivery. Women in the disease comparison group presented a significant moderate increased risk of vaginal bleeding in early pregnancy (aOR, 1.22; 95% CI, 1.06-1.39) and midpregnancy (aOR, 1.28; 95% CI, 1.07-1.55) but not postpartum.Among this Norwegian cohort of pregnant women, use of antidepressants in pregnancy was not associated with any obstetrical bleeding outcome.

Variable angle spectroscopic ellipsometric characterization of HfO2 thin film

NASA Astrophysics Data System (ADS)

Kumar, M.; Kumari, N.; Karar, V.; Sharma, A. L.

2018-02-01

Hafnium Oxide film was deposited on BK7 glass substrate using reactive oxygenated E-Beam deposition technique. The film was deposited using in-situ quartz crystal thickness monitoring to control the film thickness and rate of evaporation. The thin film was grown with a rate of deposition of 0.3 nm/s. The coated substrate was optically characterized using spectrophotometer to determine its transmission spectra. The optical constants as well as film thickness of the hafnia film were extracted by variable angle spectroscopic ellipsometry with Cauchy fitting at incidence angles of 65˚, 70˚ and 75˚.

Product energy distributions and energy partitioning in O atom reactions on surfaces

NASA Technical Reports Server (NTRS)

Halpern, Bret; Kori, Moris

1987-01-01

Surface reactions involving O atoms are likely to be highly exoergic, with different consequences if energy is channeled mostly to product molecules or surface modes. Thus the surface may become a source of excited species which can react elsewhere, or a sink for localized heat deposition which may disrupt the surface. The vibrational energy distribution of the product molecule contains strong clues about the flow of released energy. Two instructive examples of energy partitioning at surfaces are the Pt catalyzed oxidations: (1) C(ads) + O(ads) yields CO* (T is greater than 1000 K); and (2) CO(ads) + O(gas) yields CO2* (T is approx. 300 K). The infrared emission spectra of the excited product molecules were recorded and the vibrational population distributions were determined. In reaction 1, energy appeared to be statistically partitioned between the product CO and several Pt atoms. In reaction 2, partitioning was non-statistical; the CO2 asymmetric stretch distribution was inverted. In gas reactions these results would indicate a long lived and short lived activated complex. The requirement that Pt be heated in O atoms to promote reaction of atomic O and CO at room temperature is specifically addressed. Finally, the fraction of released energy that is deposited in the catalyst is estimated.

Optical and structural properties of cadmium telluride films grown by glancing angle deposition

NASA Astrophysics Data System (ADS)

Ehsani, M. H.; Rezagholipour Dizaji, H.; Azizi, S.; Ghavami Mirmahalle, S. F.; Siyanaki, F. Hosseini

2013-08-01

Cadmium telluride films were grown by the glancing angle deposition (GLAD) technique. The samples were prepared under different incident deposition flux angles (α = 0°, 20° and 70° measured from the normal to the substrate surface). During deposition, the substrate temperature was maintained at room temperature. The structural study was performed using an x-ray diffraction diffractometer. The samples were found to be poly-crystalline with cubic structure for those deposited at α = 0° and 20° and hexagonal structure for the one deposited at 70°. The images of samples obtained by the field emission scanning electron microscopy technique showed that the GLAD method could produce a columnar layer tilted toward the incident deposition flux. The optical properties study by the UV-Vis spectroscopy technique showed that the use of this growth technique affected the optical properties of the films. A higher absorption coefficient in the visible and near-IR spectral range was observed for the sample deposited at α = 70°. This is an important result from the photovoltaic applications point of view where absorber materials with large absorption coefficients are needed. Also, it seems that the sample with a high incident deposition flux angle has the capability of making an n-CdTe/p-CdTe homo-junction.

Obsessive-compulsive disorder and its relationship with disgust vulnerability and conscientiousness.

PubMed

Inchausti, Felix; Delgado, Ana R; Prieto, Gerardo

2015-01-01

The aim of this study was to analyze the relationship between Obsessive-Compulsive Disorder (OCD) symptoms, disgust vulnerability, and the Five Factor Model (FFM) of personality. The sample consisted of 100 adult patients with OCD as a primary diagnosis and 246 with other anxiety disorders (OADs), who responded to OCD, disgust vulnerability, anxiety, depression and personality questionnaires. To perform parametric statistical calculations, all questionnaire scores were transformed from raw ordinal-scale scores to Rasch measures, with interval properties. OCD patients scored significantly higher than OAD patients on DPSS-R Disgust Sensitivity and DPSS-R Disgust Propensity, with a large effect size observed on Disgust Propensity. Furthermore, strong correlations were observed between DPSS-R Propensity to Disgust model scores and DOCS Contamination model scores. Finally, NEO FFI Conscientiousness trait was significantly higher in OCD patients.

Theoretical study of water-gas shift reaction on the silver nanocluster

NASA Astrophysics Data System (ADS)

Arab, Ali; Sharafie, Darioush; Fazli, Mostafa

2017-10-01

The kinetics of water gas shift reaction (WGSR) on the silver nanocluster was investigated using density functional theory according to the carboxyl associative mechanism. The hybrid B3PW91 functional along with the 6-31+G* and LANL2DZ basis sets were used throughout the calculations. It was observed that CO and H2O molecules adsorb physically on the Ag5 cluster without energy barrier as the initial steps of WGSR. The next three steps including H2Oads dissociation, carboxyl (OCOHads) formation, and CO2(ads) formation were accompanied by activation barrier. Transition states, as well as energy profiles of these three steps, were determined and analyzed. Our results revealed that the carboxyl and CO2(ads) formation were fast steps whereas H2Oads dissociation was the slowest step of WGSR.

Outcome of depression and anxiety after war: a prospective epidemiologic study of children and adolescents.

PubMed

Karam, Elie G; Fayyad, John; Karam, Aimee N; Melhem, Nadine; Mneimneh, Zeina; Dimassi, Hani; Tabet, Caroline Cordahi

2014-04-01

Prospective studies of children exposed to war have not investigated disorders other than posttraumatic stress disorder (PTSD) and have methodological limitations. From a stratified random sample of 386 children and adolescents who had been interviewed 3 weeks after war exposure (Phase 1) a random subsample (N = 143) was interviewed a year later (Phase 2). PTSD, major depressive disorder (MDD), separation anxiety disorder (SAD), overanxious disorder (OAD), and psychosocial stressors were assessed using structured interviews administered to both children and adolescents and their parents. The prevalence of disorders among the 143 at Phase 1 was MDD 25.9%, SAD 16.1%, OAD 28.0%, and PTSD 26.0%, with 44.1% having any disorder. At Phase 2 the prevalence was MDD, 5.6%; SAD, 4.2%; OAD, 0%; and PTSD, 1.4%, with 9.2% having any disorder. Occurrence of disorders at Phase 1 was associated with older age, prewar disorders, financial problems, fear of being beaten, and witnessing any war event (ORs ranged from 2.5 to 28.6). Persistence of disorders to Phase 2 was associated with prewar disorders (OR = 6.0) and witnessing any war event (OR = 14.3). There are implications for detection of at-risk cases following wars by screening for adolescents exposed to family violence, those with prewar disorders, and those who directly witnessed war events to target them for specific interventions. Copyright © 2014 International Society for Traumatic Stress Studies.

The TJO-OAdM Robotic Observatory: the scheduler

NASA Astrophysics Data System (ADS)

Colomé, Josep; Casteels, Kevin; Ribas, Ignasi; Francisco, Xavier

2010-07-01

The Joan Oró Telescope at the Montsec Astronomical Observatory (TJO - OAdM) is a small-class observatory working under completely unattended control, due to the isolation of the site. Robotic operation is mandatory for its routine use. The level of robotization of an observatory is given by its reliability in responding to environment changes and by the required human interaction due to possible alarms. These two points establish a level of human attendance to ensure low risk at any time. But there is another key point when deciding how the system performs as a robot: the capability to adapt the scheduled observation to actual conditions. The scheduler represents a fundamental element to fully achieve an intelligent response at any time. Its main task is the mid- and short-term time optimization and it has a direct effect on the scientific return achieved by the observatory. We present a description of the scheduler developed for the TJO - OAdM, which is separated in two parts. Firstly, a pre-scheduler that makes a temporary selection of objects from the available projects according to their possibility of observation. This process is carried out before the beginning of the night following different selection criteria. Secondly, a dynamic scheduler that is executed any time a target observation is complete and a new one must be scheduled. The latter enables the selection of the best target in real time according to actual environment conditions and the set of priorities.

Effect of angle of deposition on the Fractal properties of ZnO thin film surface

NASA Astrophysics Data System (ADS)

Yadav, R. P.; Agarwal, D. C.; Kumar, Manvendra; Rajput, Parasmani; Tomar, D. S.; Pandey, S. N.; Priya, P. K.; Mittal, A. K.

2017-09-01

Zinc oxide (ZnO) thin films were prepared by atom beam sputtering at various deposition angles in the range of 20-75°. The deposited thin films were examined by glancing angle X-ray diffraction and atomic force microscopy (AFM). Scaling law analysis was performed on AFM images to show that the thin film surfaces are self-affine. Fractal dimension of each of the 256 vertical sections along the fast scan direction of a discretized surface, obtained from the AFM height data, was estimated using the Higuchi's algorithm. Hurst exponent was computed from the fractal dimension. The grain sizes, as determined by applying self-correlation function on AFM micrographs, varied with the deposition angle in the same manner as the Hurst exponent.

Thermal expansion coefficients of obliquely deposited MgF2 thin films and their intrinsic stress.

PubMed

Jaing, Cheng-Chung

2011-03-20

This study elucidates the effects of columnar angles and deposition angles on the thermal expansion coefficients and intrinsic stress behaviors of MgF2 films with columnar microstructures. The behaviors associated with temperature-dependent stresses in the MgF2 films are measured using a phase-shifting Twyman-Green interferometer with a heating stage and the application of a phase reduction algorithm. The thermal expansion coefficients of MgF2 films at various columnar angles were larger than those of glass substrates. The intrinsic stress in the MgF2 films with columnar microstructures was compressive, while the thermal stress was tensile. The thermal expansion coefficients of MgF2 films with columnar microstructures and their intrinsic stress evidently depended on the deposition angle and the columnar angle.

Monitoring non-periodic comet C/2011 L4 PANSTARRS using Joan Oró 0.8 m robotic telescope at OAdM

NASA Astrophysics Data System (ADS)

Trigo-Rodríguez, J. M.; Rodríguez, D.; Lacruz, J.; Sánchez, A.

2013-09-01

Comet C/2011 L4 PANSTARRS was discovered in June 2011 by R. Wainscoat and D. Tholen using the Pan-STARRS telescope located near the summit of Haleakala, on the island of Maui in Hawaii (USA) [1]. Once its orbit was computed it was noticed its non-periodic nature and the favorable geometry during its approach to perihelion in March 2013. It first became visible to the naked eye from the Southern hemisphere, and later on it started to be seen during mid-March from the Northern one. Due to the limited observational period in right conditions we introduce here some observations obtained taken from robotic 0.8 m Telescope Joan Oró (JO) from the Observatori Astronòmic del Montsec (OAdM: www.oadm.cat) and other Spanish observatories.

Strong Surface Diffusion Mediated Glancing-Angle Deposition: Growth, Recrystallization and Reorientation of Tin Nanorods

NASA Astrophysics Data System (ADS)

Wang, Huan-Hua; Shi, Yi-Jian; William, Chu; Yigal, Blum

2008-01-01

Different from usual glancing-angle deposition where low surface diffusion is necessary to form nanorods, strong surface diffusion mediated glancing-angle deposition is exemplified by growing tin nanorod films on both silicon and glass substrates simultaneously via thermal evaporation. During growth, the nanorods were simultaneously baked by the high-temperature evaporator, and therefore re-crystallized into single crystals in consequence of strong surface diffusion. The monocrystalline tin nanorods have a preferred orientation perpendicular to the substrate surface, which is quite different from the usual uniformly oblique nanorods without recrystallization.

Fabrication of surfaces with extremely high contact angle hysteresis from polyelectrolyte multilayer.

PubMed

Wang, Liming; Wei, Jingjing; Su, Zhaohui

2011-12-20

High contact angle hysteresis on polyelectrolyte multilayers (PEMs) ion-paired with hydrophobic perfluorooctanoate anions is reported. Both the bilayer number of PEMs and the ionic strength of deposition solutions have significant influence on contact angle hysteresis: higher ionic strength and greater bilayer number cause increased contact angle hysteresis values. The hysteresis values of ~100° were observed on smooth PEMs and pinning of the receding contact line on hydrophilic defects is implicated as the cause of hysteresis. Surface roughness can be used to further tune the contact angle hysteresis on the PEMs. A surface with extremely high contact angle hysteresis of 156° was fabricated when a PEM was deposited on a rough substrate coated with submicrometer scale silica spheres. It was demonstrated that this extremely high value of contact angle hysteresis resulted from the penetration of water into the rough asperities on the substrate. The same substrate hydrophobized by chemical vapor deposition of 1H,1H,2H,2H-perfluorooctyltriethoxysilane exhibits high advancing contact angle and low hysteresis. © 2011 American Chemical Society

Scaling behavior of the surface roughness of platinum films grown by oblique angle deposition

NASA Astrophysics Data System (ADS)

Dolatshahi-Pirouz, A.; Hovgaard, M. B.; Rechendorff, K.; Chevallier, J.; Foss, M.; Besenbacher, F.

2008-03-01

Thin platinum films with well-controlled rough surface morphologies are grown by e-gun evaporation at an oblique angle of incidence between the deposition flux and the substrate normal. Atomic force microscopy is used to determine the root-mean-square value w of the surface roughness on the respective surfaces. From the scaling behavior of w , we find that while the roughness exponent α remains nearly unchanged at about 0.90, the growth exponent β changes from 0.49±0.04 to 0.26±0.01 as the deposition angle approaches grazing incidence. The values of the growth exponent β indicate that the film growth is influenced by both surface diffusion and shadowing effects, while the observed change from 0.49 to 0.26 can be attributed to differences in the relative importance of diffusion and shadowing with the deposition angle.

Controlling the Transient Interface Shape and Deposition Profile Left by Desiccation of Colloidal Droplets on Multiple Polymer Surfaces

NASA Astrophysics Data System (ADS)

Dunning, Peter David

A colloidal suspension is a small constituent of insoluble solid particles suspended in a liquid medium. Control over the wetting, evaporation, and deposition patterns left by colloidal suspensions is valuable in many biological, medical, industrial, and agricultural applications. Understanding the governing principles of wetting and evaporative phenomena of these colloidal suspensions may lead to greater control over resultant deposition patterns. Perhaps the most familiar pattern forms when an initially heterogeneous colloidal suspension leaves a dark ring pattern at the edge of a drop. This pattern is referred to as a coffee-stain and it can be seen from dried droplets of spilled coffee. This coffee-stain effect was first investigated by Deegan et. al. who discovered that these patterns occur when outward radial flows driven by evaporation at the triple contact line dominate over other effects. While the presence of coffee-stain patterns is undesirable in many printing and medical diagnostic processes, it can also be advantageous in the production of low cost transparent conductive films, the deposition of metal vapor, and the manipulation of biological structures. Controlling the interactions between the substrate, liquid, vapor, and particles can lead to control over the size and morphology of evaporative deposition patterns left by aqueous colloidal suspensions. Several methods have been developed to control the evaporation of colloidal suspensions to either suppress or enhance the coffee stain effect. Electrowetting on Dielectric (EWOD) is one promising method that has been used to control colloidal depositions by applying either an AC or DC electric field. EWOD actuation has the potential to dynamically control colloidal deposition left by desiccated droplets to either suppress or enhance the coffee stain effect. It may also allow for independent control of the fluidic interface and deposition of particles via electrowetting and electrokinetic forces. Implementation of this technique requires that the colloidal droplet be separated from the active electrode by a dielectric layer to prevent electrolysis. A variety of polymer layers have been used in EWOD devices for a variety of applications. In applications that involve desiccation of colloidal suspensions, the material for this layer should be chosen carefully as it can play an important role in the resulting deposition pattern. An experimental method to monitor the transient evolution of the shape of an evaporating colloidal droplet and optically quantify the resultant deposition pattern is presented. Unactuated colloidal suspensions will be desiccated on a variety of substrates commonly used in EWOD applications. Transient image profiles and particle deposition patterns are examined for droplets containing fluorescent micro-particles. Qualitative and quantitative comparisons of these results will be used to compare multiple different cases in an effort to provide insight into the effects of polymer selection on the drying dynamics and resultant deposition patterns of desiccated colloidal materials. It was found that the equilibrium and receding contact angles between the surface and the droplet play a key role in the evaporation dynamics and the resulting deposition patterns left by a desiccated colloidal suspension. The equilibrium contact angle controls the initial contact diameter for a droplet of a given volume. As a droplet on a surface evaporates, the evolution of the interface shape and the contact diameter can generally be described by three different regimes. The Constant Contact Radius (CCR) regime occurs when the contact line is pinned while the contact angle decreases. The Constant Contact Angle (CCA) regime occurs when the contact line recedes while the contact angle remains constant. The Mixed regime occurs when the contact radius and angle both reduce over time. The presence of the CCA regime allows the contact line to recede creating a more uniform deposition. However, not all droplets move into the CCA regime. Some remain in the CCR regime creating a coffee-stain pattern. In order to transition into the CCA regime, the dynamic contact angle of the droplet must be reduced to an angle close to the receding contact angle. Transient interface shapes and deposition patterns were examined on four surfaces: (i) Glass, (ii) Kapton HN polyimide tape, (iii) SU-8 3005, and (iv) Teflon AF. Glass has a low equilibrium contact angle and a very low receding contact angle resulting in a large uniform coffee-stain deposition. Kapton HN and SU-8 3005 have similar equilibrium contact angles that result in similar initial contact diameters. However, Kapton HN pins at that initial diameter due to a low receding contact angle producing a smaller more intense coffee-stain. SU-8 3005 has a large receding contact angle that allows for the transition into the CCA regime which results in a smaller, more uniform, and more intense spot. Teflon AF has the largest equilibrium and receding contact angle producing the smallest, most uniform, and most intense spot. Results presented here suggest that a lower receding contact angle is beneficial in areas where the coffee-stain effect needs to be enhanced while a larger receding contact angle is beneficial in areas where the coffee-stain needs to be suppressed. Preliminary results are also presented examining droplets actuated via AC electrowetting to examine the effect of electrode geometry and applied voltage on electrowetting behavior and colloidal depositions in these cases. It was found that the Young-Lippmann equation needs to be modified to satisfy the modified capacitance per unit area of a system with different electrode geometries.

Efficacy of combining ING4 and TRAIL genes in cancer-targeting gene virotherapy strategy: first evidence in preclinical hepatocellular carcinoma.

PubMed

Galal El-Shemi, A; Mohammed Ashshi, A; Oh, E; Jung, B-K; Basalamah, M; Alsaegh, A; Yun, C-O

2018-01-01

Current treatments of hepatocellular carcinoma (HCC) are ineffective and unsatisfactory in many aspects. Cancer-targeting gene virotherapy using oncolytic adenoviruses (OAds) armed with anticancer genes has shown efficacy and safety in clinical trials. Nowadays, both inhibitor of growth 4 (ING4), as a multimodal tumor suppressor gene, and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), as a potent apoptosis-inducing gene, are experiencing a renaissance in cancer gene therapy. Herein we investigated the antitumor activity and safety of mono- and combined therapy with OAds armed with ING4 (Ad-ΔB/ING4) and TRAIL (Ad-ΔB/TRAIL) gene, respectively, on preclinical models of human HCC. OAd-mediated expression of ING4 or TRAIL transgene was confirmed. Ad-ΔB/TRAIL and/or Ad-ΔB/ING4 exhibited potent killing effect on human HCC cells (HuH7 and Hep3B) but not on normal liver cells. Most importantly, systemic therapy with Ad-ΔB/ING4 plus Ad-ΔB/TRAIL elicited more eradicative effect on an orthotopic mouse model of human HCC than their monotherapy, without causing obvious overlapping toxicity. Mechanistically, Ad-ΔB/ING4 and Ad-ΔB/TRAIL were remarkably cooperated to induce antitumor apoptosis and immune response, and to repress tumor angiogenesis. This is the first study showing that concomitant therapy with Ad-ΔB/ING4 and Ad-ΔB/TRAIL may provide a potential strategy for HCC therapy and merits further investigations to realize its possible clinical translation.

[Preparation and transmissivity of ZnS nanocolumn thin films with glancing angle deposition technology].

PubMed

Lu, Li-Fang; Xu, Zheng; Zhang, Fu-Jun; Zhao, Su-Ling; Song, Dan-Dan; Li, Jun-Ming; Wang, Yong-Sheng; Xu, Xu-Rong

2010-02-01

Nanocrystalline ZnS thin films were fabricated by glancing angle deposition (GLAD) technology in an electron beam evaporation system. Deposition was carried out in the custom vacuum chamber at a base pressure 3 x 10(-4) Pa, and the deposition rate was fixed at 0.2 nm x s(-1). ZnS films were deposited on pieces of indium tin oxide (ITO) substrates when the oblique angle of the substrate relative to the incoming molecular flux was set to 0 degrees, 80 degrees and 85 degrees off the substrate normal respectively. X-ray diffraction (XRD) spectra and scanning electron microscope (SEM) images showed that ZnS nanocrystalline films were formed on the substrates at different oblique angle, but the nanocolumn structure was only formed under the situation of alpha = 80 degrees and 85 degrees. The dynamics during the deposition process of the ZnS films at alpha = 0 degrees, 80 degrees and 85 degrees was analyzed. The transmitted spectra of ZnS thin films deposited on ITO substrates showed that the ZnS nanocolumn thin films could enhance the transmissivity in visible range. The ZnS nanocolumn could be used into electroluminescence device, and it would enhance the luminous efficiency of the device.

Comparative efficacy of tadalafil once daily in men with erectile dysfunction who demonstrated previous partial responses to as-needed sildenafil, tadalafil, or vardenafil.

PubMed

Kim, Edward; Seftel, Allen; Goldfischer, Evan; Baygani, Simin; Burns, Patrick

2015-02-01

Phosphodiesterase type-5 inhibitors (PDE5Is) are first-line therapies for erectile dysfunction (ED). Sildenafil (SIL) and vardenafil (VAR) are approved for as-needed (PRN) dosing; tadalafil (TAD) is approved for both PRN and once-a-day (OaD) dosing for ED. Recent evidence suggests that TAD-OaD may be effective as therapy in men with an incomplete response to PRN-PDE5I therapy. This study evaluated whether TAD-OaD provides similar efficacy in men with ED who had previously demonstrated a partial response to PRN-PDE5I therapy. In this randomized, double-blind, placebo-controlled trial, men with a ≥3 month ED history received SIL 100 mg, TAD 20 mg, or VAR 20 mg during a 4 week open-label lead-in period. Those with International Index of Erectile Function - Erectile Function (IIEF-EF) domain scores <26 following lead-in treatment completed a 4 week washout period, then randomized to TAD 2.5 mg up-titrated to 5 mg, TAD 5 mg, or placebo (PBO) OaD for 12 weeks. MAIN OUTCOME MEASURES obtained from patients treated with TAD-OaD were compared to PBO-treated patients. Additionally, results of treatment with TAD-OaD were compared to results obtained from 4 week PRN-PDE5I therapy to determine whether OaD and PRN regimens provided comparable efficacy. NCT01130532. International Index of Erectile Function (IIEF) domain scores; Sexual Encounter Profile (SEP) questions 2-5. Endpoint data was obtained from 590 men (391 TAD; 199 PBO). RESULTS for all IIEF and SEP measures were significantly better for TAD-OaD (p < 0.001 for all) compared to PBO and were comparable to those observed during PRN-PDE5I treatment. TAD 2.5 mg and TAD 5 mg OaD therapy were safe and generally well tolerated. Tadalafil once daily is a viable alternative to as-needed PDE5I therapy in men with ED. Key limitations include the lack of a PRN PDE5I study group during the double-blind period, and that many more patients took tadalafil than sildenafil or vardenafil during the PRN period.

Wettability control of droplet deposition and detachment.

PubMed

Baret, Jean-Christophe; Brinkmann, Martin

2006-04-14

The conditions for droplet deposition on plane substrates are studied using electrowetting to continuously modulate the surface wettability. Droplets of controlled volume attached to the tip of a pipette are brought into contact with the surface. During retraction of the pipette the droplets are deposited or detach completely depending on volume and contact angle. The experimental limit of deposition in the contact angle or volume plane is in good agreement with analytical and numerical predictions obtained within the capillary model.

Comparative study of plasma-deposited fluorocarbon coatings on different substrates

NASA Astrophysics Data System (ADS)

Farsari, E.; Kostopoulou, M.; Amanatides, E.; Mataras, D.; Rapakoulias, D. E.

2011-05-01

The deposition of hydrophobic fluorocarbon coatings from C2F6 and C2F6-H2 rf discharges on different substrates was examined. Polyester textile, glass and two different ceramic compounds were used as substrates. The effect of the total gas pressure, the rf power dissipation and the deposition time on the hydrophobic character of the samples was investigated. Films deposited on polyester textiles at low pressure (0.03 mbar) and power consumption (16 mW cm-2) using pure C2F6 presented the highest water contact angles (~150°). On the other hand, the addition of hydrogen was necessary in order to deposit stable hydrophobic coatings on glass and ceramic substrates. Coatings deposited on glass at intermediate deposition rates (~100 Å min-1) and pressures presented the highest angles (~105°). Concerning the heavy clay ceramics, samples treated in low-pressure (0.05 mbar) and low-power (16 mW cm-2) discharges showed the highest contact angles. The deposition time was found to play an important role in the hydrophobicity and long-term behaviour of porous and rough substrates.

Effect of Pressurized Metered Dose Inhaler Spray Characteristics and Particle Size Distribution on Drug Delivery Efficiency.

PubMed

Yousefi, Morteza; Inthavong, Kiao; Tu, Jiyuan

2017-10-01

A key issue in pulmonary drug delivery is improvement of the delivery device for effective and targeted treatment. Pressurized metered dose inhalers (pMDIs) are the most popular aerosol therapy device for treating lung diseases. This article studies the effect of spray characteristics: injection velocity, spray cone angle, particle size distribution (PSD), and its mass median aerodynamic diameter (MMAD) on drug delivery. An idealized oral airway geometry, extending from mouth to the main bronchus, was connected to a pMDI device. Inhalation flow rates of 15, 30, and 60 L/min were used and drug particle tracking was a one-way coupled Lagrangian model. The results showed that most particles deposited in the pharynx, where the airway has a reduced cross-sectional area. Particle deposition generally decreased with initial spray velocity and with increased spray cone angle for 30 and 60 L/min flow rates. However, for 15 L/min flow rate, the deposition increased slightly with an increase in the spray velocity and cone angle. The effect of spray cone angle was more significant than the initial spray velocity on particle deposition. When the MMAD of a PSD was reduced, the deposition efficiency also reduces, suggesting greater rates of particle entry into the lung. The deposition rate showed negligible change when the MMAD was more than 8 μm. Spray injection angle and velocity change the drug delivery efficacy; however, the efficiency shows more sensitivity to the injection angle. The 30 L/min airflow rate delivers spray particles to the lung more efficiently than 15 and 60 L/min airflow rate, and reducing MMAD can help increase drug delivery to the lung.

Linac head scatter factor for asymmetric radiation field

NASA Astrophysics Data System (ADS)

Soubra, Mazen Ahmed

1997-11-01

The head scatter factor, Sh is an important dosimetric quantity used in radiation therapy dose calculation. It is empirically determined and its field size dependence reflects changes in photon scatter from components in the linac treatment head. In this work a detailed study of the physical factors influencing the determination of Sh was performed with particular attention given to asymmetric field geometries. Ionization measurements for 6 and 18 MV photon beams were made to examine the factors which determine Sh. These include: phantom size and material, collimator backscatter, non-lateral electronic equilibrium (LEE) conditions, electron contamination, collimator-exchange, photon energy, flattening filter and off-axis distance (OAD). Results indicated that LEE is not required for Sh measurements if electron contamination is minimized. Brass caps or polystyrene miniphantoms can both be used in Sh measurements provided the phantom thickness is large enough to stop contaminant electrons. Backscatter radiation effects into the monitor chamber were found to be negligible for the Siemens linac. It was found that the presence and shape of the flattening filter had a significant effect on the empirically determined value of Sh was also shown to be a function of OAD, particularly for small fields. For fields larger than 12×12 cm2/ Sh was independent of OAD. A flattening filter mass model was introduced to explain qualitatively the above results. A detailed Monte Carlo simulation of the Siemens KD2 linac head in 6 MV mode was performed to investigate the sources of head scatter which contribute to the measured Sh. The simulated head components include the flattening filter, the electron beam stopper, the primary collimator, the photon monitor chamber and the secondary collimators. The simulations showed that the scatter from the head of the Siemens linac is a complex function of the head components. On the central axis the flattening filter played the dominant role in the contributing to scatter. However this role was significantly reduced off- axis and other head components, such as the electron beam stopper and the primary collimator, became more important. The role of the mirror and ion chamber was relatively minor. Scatter from the secondary collimators was shown to be a function of the filed size and the position of the collimators in the treatment head. They were also found to play a dual role, both as a scatter source and as an attenuator for scatter produced upstream in the linac head. A closed form model, based on the work of Yu and Slobada, was developed to estimate head scatter factors for on- and off-axis asymmetric fields. The model requires three parameters to fit the measured data. The first, a constant c, has a physical significance and is independent of energy and off-axis distance. The second, g, shows a small variation with the energy and OAD while the third parameter, the primary-to-scatter ratio, is strongly dependent on energy and off-axis distance. Comparison of Sh, predicted by the model, to measurement for a large range of symmetric and asymmetric fields showed excellent agreement. A maximum of 0.7% discrepancy was observed at 12 cm OAD.

What Do Childhood Anxiety Disorders Predict?

ERIC Educational Resources Information Center

Bittner, Antje; Egger, Helen L.; Erkanli, Alaattin; Costello, E. Jane; Foley, Debra L.; Angold, Adrian

2007-01-01

Background: Few longitudinal studies of child and adolescent psychopathology have examined the links between specific childhood anxiety disorders and adolescent psychiatric disorder. In this paper we test the predictive specificity of separation anxiety disorder (SAD), overanxious disorder (OAD), generalized anxiety disorder (GAD), and social…

Hydrophobic and optical characteristics of graphene and graphene oxide films transferred onto functionalized silica particles deposited glass surface

NASA Astrophysics Data System (ADS)

Yilbas, B. S.; Ibrahim, A.; Ali, H.; Khaled, M.; Laoui, T.

2018-06-01

Hydrophobic and optical transmittance characteristics of the functionalized silica particles on the glass surface prior and after transfer of graphene and graphene oxide films on the surface are examined. Nano-size silica particles are synthesized and functionalized via chemical grafting and deposited onto a glass surface. Graphene film, grown on copper substrate, was transferred onto the functionalized silica particles surface through direct fishing method. Graphene oxide layer was deposited onto the functionalized silica particles surface via spin coating technique. Morphological, hydrophobic, and optical characteristics of the functionalized silica particles deposited surface prior and after graphene and graphene oxide films transfer are examined using the analytical tools. It is found that the functionalized silica particles are agglomerated at the surface forming packed structures with few micro/nano size pores. This arrangement gives rise to water droplet contact angle and contact angle hysteresis in the order of 163° and 2°, respectively, and remains almost uniform over the entire surface. Transferring graphene and depositing graphene oxide films over the functionalized silica particles surface lowers the water droplet contact angle slightly (157-160°) and increases the contact angle hysteresis (4°). The addition of the graphene and graphene oxide films onto the surface of the deposited functionalized silica particles improves the optical transmittance.

Angular dependence of etch rates in the etching of poly-Si and fluorocarbon polymer using SF6, C4F8, and O2 plasmas

NASA Astrophysics Data System (ADS)

Min, Jae-Ho; Lee, Gyeo-Re; Lee, Jin-Kwan; Moon, Sang Heup; Kim, Chang-Koo

2004-05-01

The dependences of etch rates on the angle of ions incident on the substrate surface in four plasma/substrate systems that constitute the advanced Bosch process were investigated using a Faraday cage designed for the accurate control of the ion-incident angle. The four systems, established by combining discharge gases and substrates, were a SF6/poly-Si, a SF6/fluorocarbon polymer, an O2/fluorocarbon polymer, and a C4F8/Si. In the case of SF6/poly-Si, the normalized etch rates (NERs), defined as the etch rates normalized by the rate on the horizontal surface, were higher at all angles than values predicted from the cosine of the ion-incident angle. This characteristic curve shape was independent of changes in process variables including the source power and bias voltage. Contrary to the earlier case, the NERs for the O2/polymer decreased and eventually reached much lower values than the cosine values at angles between 30° and 70° when the source power was increased and the bias voltage was decreased. On the other hand, the NERs for the SF6/polymer showed a weak dependence on the process variables. In the case of C4F8/Si, which is used in the Bosch process for depositing a fluorocarbon layer on the substrate surface, the deposition rate varied with the ion incident angle, showing an S-shaped curve. These characteristic deposition rate curves, which were highly dependent on the process conditions, could be divided into four distinct regions: a Si sputtering region, an ion-suppressed polymer deposition region, an ion-enhanced polymer deposition region, and an ion-free polymer deposition region. Based on the earlier characteristic angular dependences of the etch (or deposition) rates in the individual systems, ideal process conditions for obtaining an anisotropic etch profile in the advanced Bosch process are proposed. .

Profiling of Extracellular Toxins Associated with Diarrhetic Shellfish Poison in Prorocentrum lima Culture Medium by High-Performance Liquid Chromatography Coupled with Mass Spectrometry

PubMed Central

Pan, Lei; Chen, Junhui; Shen, Huihui; He, Xiuping; Li, Guangjiu; Song, Xincheng; Zhou, Deshan; Sun, Chengjun

2017-01-01

Extracellular toxins released by marine toxigenic algae into the marine environment have attracted increasing attention in recent years. In this study, profiling, characterization and quantification of extracellular toxin compounds associated with diarrhetic shellfish poison (DSP) in the culture medium of toxin-producing dinoflagellates were performed using high-performance liquid chromatography–high-resolution mass spectrometry/tandem mass spectrometry for the first time. Results showed that solid-phase extraction can effectively enrich and clean the DSP compounds in the culture medium of Prorocentrum lima (P. lima), and the proposed method achieved satisfactory recoveries (94.80%–100.58%) and repeatability (relative standard deviation ≤9.27%). Commercial software associated with the accurate mass information of known DSP toxins and their derivatives was used to screen and identify DSP compounds. Nine extracellular DSP compounds were identified, of which seven toxins (including OA-D7b, OA-D9b, OA-D10a/b, and so on) were found in the culture medium of P. lima for the first time. The results of quantitative analysis showed that the contents of extracellular DSP compounds in P. lima culture medium were relatively high, and the types and contents of intracellular and extracellular toxins apparently varied in the different growth stages of P. lima. The concentrations of extracellular okadaic acid and dinophysistoxin-1 were within 19.9–34.0 and 15.2–27.9 μg/L, respectively. The total concentration of the DSP compounds was within the range of 57.70–79.63 μg/L. The results showed that the proposed method is an effective tool for profiling the extracellular DSP compounds in the culture medium of marine toxigenic algae. PMID:28974018

Postauthorization safety study of the DPP-4 inhibitor saxagliptin: a large-scale multinational family of cohort studies of five outcomes.

PubMed

Lo Re, Vincent; Carbonari, Dena M; Saine, M Elle; Newcomb, Craig W; Roy, Jason A; Liu, Qing; Wu, Qufei; Cardillo, Serena; Haynes, Kevin; Kimmel, Stephen E; Reese, Peter P; Margolis, David J; Apter, Andrea J; Reddy, K Rajender; Hennessy, Sean; Bhullar, Harshvinder; Gallagher, Arlene M; Esposito, Daina B; Strom, Brian L

2017-01-01

To evaluate the risk of serious adverse events among patients with type 2 diabetes mellitus initiating saxagliptin compared with oral antidiabetic drugs (OADs) in classes other than dipeptidyl peptidase-4 (DPP-4) inhibitors. Cohort studies using 2009-2014 data from two UK medical record data sources (Clinical Practice Research Datalink, The Health Improvement Network) and two USA claims-based data sources (HealthCore Integrated Research Database, Medicare). All eligible adult patients newly prescribed saxagliptin (n=110 740) and random samples of up to 10 matched initiators of non-DPP-4 inhibitor OADs within each data source were selected (n=913 384). Outcomes were hospitalized major adverse cardiovascular events (MACE), acute kidney injury (AKI), acute liver failure (ALF), infections, and severe hypersensitivity events, evaluated using diagnostic coding algorithms and medical records. Cox regression was used to determine HRs with 95% CIs for each outcome. Meta-analyses across data sources were performed for each outcome as feasible. There were no increased incidence rates or risk of MACE, AKI, ALF, infection, or severe hypersensitivity reactions among saxagliptin initiators compared with other OAD initiators within any data source. Meta-analyses demonstrated a reduced risk of hospitalization/death from MACE (HR 0.91, 95% CI 0.85 to 0.97) and no increased risk of hospitalization for infection (HR 0.97, 95% CI 0.93 to 1.02) or AKI (HR 0.99, 95% CI 0.88 to 1.11) associated with saxagliptin initiation. ALF and hypersensitivity events were too rare to permit meta-analysis. Saxagliptin initiation was not associated with increased risk of MACE, infection, AKI, ALF, or severe hypersensitivity reactions in clinical practice settings. NCT01086280, NCT01086293, NCT01086319, NCT01086306, and NCT01377935; Results.

Altered Disease Course after Initiation of Self-Monitoring of Blood Glucose in Noninsulin-Treated Type 2 Diabetes (ROSSO 3)

PubMed Central

Kolb, Hubert; Schneider, Berthold; Heinemann, Lutz; Lodwig, Volker; Scherbaum, Werner A.; Martin, Stephan

2007-01-01

Background Patients with noninsulin-treated type 2 diabetes were documented from diagnosis to determine whether patients taking up self-monitoring of blood glucose (SMBG) are distinct by baseline characteristics, exhibit a different natural disease course, and are treated differently. Methods The German multicenter, retrospective cohort study (ROSSO) followed 3268 persons from diagnosis of type 2 diabetes for a mean of 6.5 years. During follow-up, 1912 persons received oral antidiabetic agents (OAD) for at least 1 year, but no insulin. Data were retrieved from patient files of randomly contacted primary care practices. Results During follow-up, 742 patients (38.8%) began with SMBG prior to an end point. Initiation of SMBG was followed by improved glycemic control. Patients in the SMBG cohort were treated more often by an internist, younger by a mean of 3 years, and more often male (p < 0.001, each). A higher percentage of persons in the SMBG cohort were treated with metformin (74.7% vs 65.0%, p < 0.001) or changed OAD therapy (66.3% of patients vs 48.3% of patients, p < 0.001). SMBG was not accompanied by more comedication. In the SMBG cohort, 68 persons had a clinical end point (myocardial infarction, stroke, foot amputation, blindness, hemodialysis, or all-cause mortality) (9.2%) compared to 155 persons (13.2%) in the cohort without SMBG (p = 0.04 after multivariate adjustments). Conclusion This first large documentation of OAD-treated persons from diagnosis for 6.5 years indicates that the use of SMBG is associated with younger age at diagnosis, a higher prescription rate of metformin, more frequent changes of oral therapy, and a lower risk of a clinical end point. PMID:19885111

Profiling of Extracellular Toxins Associated with Diarrhetic Shellfish Poison in Prorocentrum lima Culture Medium by High-Performance Liquid Chromatography Coupled with Mass Spectrometry.

PubMed

Pan, Lei; Chen, Junhui; Shen, Huihui; He, Xiuping; Li, Guangjiu; Song, Xincheng; Zhou, Deshan; Sun, Chengjun

2017-09-30

Extracellular toxins released by marine toxigenic algae into the marine environment have attracted increasing attention in recent years. In this study, profiling, characterization and quantification of extracellular toxin compounds associated with diarrhetic shellfish poison (DSP) in the culture medium of toxin-producing dinoflagellates were performed using high-performance liquid chromatography-high-resolution mass spectrometry/tandem mass spectrometry for the first time. Results showed that solid-phase extraction can effectively enrich and clean the DSP compounds in the culture medium of Prorocentrum lima ( P. lima ), and the proposed method achieved satisfactory recoveries (94.80%-100.58%) and repeatability (relative standard deviation ≤9.27%). Commercial software associated with the accurate mass information of known DSP toxins and their derivatives was used to screen and identify DSP compounds. Nine extracellular DSP compounds were identified, of which seven toxins (including OA-D7b, OA-D9b, OA-D10a/b, and so on) were found in the culture medium of P. lima for the first time. The results of quantitative analysis showed that the contents of extracellular DSP compounds in P. lima culture medium were relatively high, and the types and contents of intracellular and extracellular toxins apparently varied in the different growth stages of P. lima . The concentrations of extracellular okadaic acid and dinophysistoxin-1 were within 19.9-34.0 and 15.2-27.9 μg/L, respectively. The total concentration of the DSP compounds was within the range of 57.70-79.63 μg/L. The results showed that the proposed method is an effective tool for profiling the extracellular DSP compounds in the culture medium of marine toxigenic algae.

Design of experiments to optimize an in vitro cast to predict human nasal drug deposition.

PubMed

Shah, Samir A; Dickens, Colin J; Ward, David J; Banaszek, Anna A; George, Chris; Horodnik, Walter

2014-02-01

Previous studies showed nasal spray in vitro tests cannot predict in vivo deposition, pharmacokinetics, or pharmacodynamics. This challenge makes it difficult to assess deposition achieved with new technologies delivering to the therapeutically beneficial posterior nasal cavity. In this study, we determined best parameters for using a regionally divided nasal cast to predict deposition. Our study used a model suspension and a design of experiments to produce repeatable deposition results that mimic nasal deposition patterns of nasal suspensions from the literature. The seven-section (the nozzle locator, nasal vestibule, front turbinate, rear turbinate, olfactory region, nasopharynx, and throat filter) nylon nasal cast was based on computed tomography images of healthy humans. It was coated with a glycerol/Brij-35 solution to mimic mucus. After assembling and orienting, airflow was applied and nasal spray containing a model suspension was sprayed. After disassembling the cast, drug depositing in each section was assayed by HPLC. The success criteria for optimal settings were based on nine in vivo studies in the literature. The design of experiments included exploratory and half factorial screening experiments to identify variables affecting deposition (angles, airflow, and airflow time), optimization experiments, and then repeatability and reproducibility experiments. We found tilt angle and airflow time after actuation affected deposition the most. The optimized settings were flow rate of 16 L/min, postactuation flow time of 12 sec, a tilt angle of 23°, nozzle angles of 0°, and actuation speed of 5 cm/sec. Neither cast nor operator caused significant variation of results. We determined cast parameters to produce results resembling suspension nasal sprays in the literature. The results were repeatable and unaffected by operator or cast. These nasal spray parameters could be used to assess deposition from new devices or formulations. For human deposition studies using radiolabeled formulations, this cast could show that radiolabel deposition represents drug deposition. Our methods could also be used to optimize settings for other casts.

Incident flux angle induced crystal texture transformation in nanostructured molybdenum films

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, L.; Lu, T.-M.; Wang, G.-C.

2012-07-15

Molybdenum films were observed to undergo a dramatic change in crystal texture orientation when the incident flux angle was varied in an oblique angle sputter deposition on amorphous substrates. Reflection high-energy electron diffraction pole figure and scanning electron microscopy were used to analyze in detail the texture orientation of the films. The normal incident deposition resulted in a fiber texture film with the minimum energy (110) crystal plane parallel to the substrate surface. A (110)[110] biaxial texture was observed for the samples grown with low incident angles of less than 45 Degree-Sign , with respect to the surface normal. Onmore » the other hand, for an oblique angle deposition of larger than 60 Degree-Sign , a (111)[112] biaxial texture was observed and appeared to be consistent with a zone T structure where the geometrically fastest growth [001] direction of a crystal plays a dominant role in defining the texture. We argue that a structural transition had occurred when the incident flux was varied from near normal incidence to a large angle.« less

Nanoliter-Scale Oil-Air-Droplet Chip-Based Single Cell Proteomic Analysis.

PubMed

Li, Zi-Yi; Huang, Min; Wang, Xiu-Kun; Zhu, Ying; Li, Jin-Song; Wong, Catherine C L; Fang, Qun

2018-04-17

Single cell proteomic analysis provides crucial information on cellular heterogeneity in biological systems. Herein, we describe a nanoliter-scale oil-air-droplet (OAD) chip for achieving multistep complex sample pretreatment and injection for single cell proteomic analysis in the shotgun mode. By using miniaturized stationary droplet microreaction and manipulation techniques, our system allows all sample pretreatment and injection procedures to be performed in a nanoliter-scale droplet with minimum sample loss and a high sample injection efficiency (>99%), thus substantially increasing the analytical sensitivity for single cell samples. We applied the present system in the proteomic analysis of 100 ± 10, 50 ± 5, 10, and 1 HeLa cell(s), and protein IDs of 1360, 612, 192, and 51 were identified, respectively. The OAD chip-based system was further applied in single mouse oocyte analysis, with 355 protein IDs identified at the single oocyte level, which demonstrated its special advantages of high enrichment of sequence coverage, hydrophobic proteins, and enzymatic digestion efficiency over the traditional in-tube system.

Study of nanostructure and ethanol vapor sensing performance of WO3 thin films deposited by e-beam evaporation method under different deposition angles: application in breath analysis devices

NASA Astrophysics Data System (ADS)

Amani, E.; Khojier, K.; Zoriasatain, S.

2018-01-01

This paper studies the effect of deposition angle on the crystallographic structure, surface morphology, porosity and subsequently ethanol vapor sensing performance of e-beam-evaporated WO3 thin films. The WO3 thin films were deposited by e-beam evaporation technique on SiO2/Si substrates under different deposition angles (0°, 30°, and 60°) and then post-annealed at 500 °C with a flow of oxygen for 4 h. Crystallographic structure and surface morphology of the samples were checked using X-ray diffraction method and atomic force microscopy, respectively. Physical adsorption isotherm was also used to measure the porosity and effective surface area of the samples. The electrical response of the samples was studied to different concentrations of ethanol vapor (10-50 ppm) at the temperature range of 140-260 °C and relative humidity of 80%. The results reveal that the WO3 thin film deposited under 30° angle shows more sensitivity to ethanol vapor than the other samples prepared in this work due to the more crystallinity, porosity, and effective surface area. The investigations also show that the sample deposited at 30° can be a good candidate as a breath analysis device at the operating temperature of 240 °C because of its high response, low detection limit, and reliability at high relative humidity.

Glancing angle deposition of Fe triangular nanoprisms consisting of vertically-layered nanoplates

NASA Astrophysics Data System (ADS)

Li, Jianghao; Li, Liangliang; Ma, Lingwei; Zhang, Zhengjun

2016-10-01

Fe triangular nanoprisms consisting of vertically-layered nanoplates were synthesized on Si substrate by glancing angle deposition (GLAD) with an electron beam evaporation system. It was found that Fe nanoplates with a crystallographic plane index of BCC (110) were stacked vertically to form triangular nanoprisms and the axial direction of the nanoprisms, BCC <001>, was normal to the substrate. The effects of experimental parameters of GLAD on the growth and morphology of Fe nanoprisms were systematically studied. The deposition rate played an important role in the morphology of Fe nanoprisms at the same length, the deposition angle just affected the areal density of nanoprisms, and the rotation speed of substrate had little influence within the parameter range we investigated. In addition, the crystal growth mechanism of Fe nanoprisms was explained with kinetically-controlled growth mechanism and zone model theory. The driving force of crystal growth was critical to the morphology and microstructure of Fe nanoprisms deposited by GLAD. Our work introduced an oriented crystal structure into the nanomaterials deposited by GLAD, which provided a new approach to manipulate the properties and functions of nanomaterials.

77 FR 20401 - Proposed Data Collections Submitted for Public Comment and Recommendations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-04

... currently in use reflect CDC's consultations with representatives of the Society for Assisted Reproductive Technology (SART), the American Society for Reproductive Medicine, and RESOLVE: the National Infertility... Integrity, Office of the Associate Director for Science (OADS), Office of the Director, Centers for Disease...

[The loss of work fitness and the course of invalidism in patients with limb vessel lesions].

PubMed

Chernenko, V F; Goncharenko, A G; Shuvalov, A Iu; Chernenko, V V; Tarasov, I V

2005-01-01

The growth of the sick rate of limb peripheral vessels associated with a severe outcome (trophic ulcers, amputation) exerts an appreciable effect on the lowering of quality of life in patients. This manifests by the prolonged loss of work fitness, change of the habitual occupation and disability establishment. Objective analytical information on this problem will be of help in the delineation of the tendencies in this direction and potential approaches to the prevention of social losses. The present work is based on an analysis of 2115 statements of medicosocial expert evaluation (MSEE) of invalids suffering from diseases of limb vessels, performed over recent 8 years in the Altai region. The decisions made by the MSEE were based on the results of the clinical examination of patients using the current diagnostic modalities (ultrasonography, duplex scanning, angiography, etc). It has been established that among persons who had undergone MSEE, over the half (64.1%) were under 60 years, i.e. in the age of work fitness. It is noteworthy that the overwhelming number of invalids were men (83%) and workers (84.2%). As for special vascular pathologies, the majority of patients presented with obliterative arterial diseases (OAD) of the lower limbs, accounting for 76.3% whereas patients with venous pathology ranked second in number (15.9%). The highest severity of invalidism (groups I and II) was also recorded in OAD (77.5%), especially in atherosclerosis obliterans (AO) which accounted for 84%. Of note, these diseases were marked by no tendency toward reduction of their incidence. The time of temporary disability (from 3 to 9 months) was also most frequently recorded in OAD of the limbs. In OAD, the temporary or persistent loss of work fitness were caused by critical ischemia and amputations whereas in venous pathology, namely in varicosity and post-thrombophlebotic syndrome, the cause was progressing CVI complicated by trophic ulcers. On the whole, the lack of changes in the lowering of the number of invalids due to the given pathology evidences the unsatisfactory results of these patients' rehabilitation and the high socioeconomic tension determined by considerable treatment expenses and the high number of the disabled. Approaches to the escape from such a situation should be looked for in the early mass screening diagnosis of vascular lesions, early drug and surgical treatment and in the refinement of the system of rehabilitation prophylactic medical examination.

Numerical analysis of deposition frequency for successive droplets coalescence dynamics

NASA Astrophysics Data System (ADS)

Cheng, Xiaoding; Zhu, Yunlong; Zhang, Lei; Zhang, Dingyi; Ku, Tao

2018-04-01

A pseudopotential based multi-relaxation-time lattice Boltzmann model is employed to investigate the dynamic behaviors of successive droplets' impact and coalescence on a solid surface. The effects of deposition frequency on the morphology of the formed line are investigated with a zero receding contact angle by analyzing the droplet-to-droplet coalescence dynamics. Two collision modes (in-phase mode and out-of-phase mode) between the pre-deposited bead and the subsequent droplet are identified depending on the deposition frequency. A uniform line can be obtained at the optimal droplet spacing in the in-phase mode (Δt* < 1.875). However, a scalloped line pattern is formed in the out-of-phase mode (Δt* > 1.875). It is found that decreasing the droplet spacing or advancing contact angle can improve the smoothness of line in the out-of-phase mode. Furthermore, the effects of deposition frequency on the morphology of the formed lines are validated to be applicable to cases with a finite receding contact angle.

Transition from stripe-like patterns to a particulate film using driven evaporating menisci.

PubMed

Noguera-Marín, Diego; Moraila-Martínez, Carmen L; Cabrerizo-Vílchez, Miguel A; Rodríguez-Valverde, Miguel A

2014-07-01

Better control of colloidal assembly by convective deposition is particularly helpful in particle templating. However, knowledge of the different factors that can alter colloidal patterning mechanisms is still insufficient. Deposit morphology is strongly ruled by contact line dynamics, but the wettability properties of the substrate can alter it drastically. In this work, we experimentally examined the roles of substrate contact angle hysteresis and receding contact angle using driven evaporating menisci similar to the dip-coating technique but at a low capillary number. We used smooth substrates with very different wettability properties and nanoparticles of different sizes. For fixed withdrawal velocity, evaporation conditions, and nanoparticle concentration, we analyzed the morphology of the deposits formed on each substrate. A gradual transition from stripe-like patterns to a film was observed as the contact angle hysteresis and receding contact angle were lowered.

Characterization of previously unidentified lunar pyroclastic deposits using Lunar Reconnaissance Orbiter Camera (LROC) data

USGS Publications Warehouse

Gustafson, J. Olaf; Bell, James F.; Gaddis, Lisa R.R.; Hawke, B. Ray Ray; Giguere, Thomas A.

2012-01-01

We used a Lunar Reconnaissance Orbiter Camera (LROC) global monochrome Wide-angle Camera (WAC) mosaic to conduct a survey of the Moon to search for previously unidentified pyroclastic deposits. Promising locations were examined in detail using LROC multispectral WAC mosaics, high-resolution LROC Narrow Angle Camera (NAC) images, and Clementine multispectral (ultraviolet-visible or UVVIS) data. Out of 47 potential deposits chosen for closer examination, 12 were selected as probable newly identified pyroclastic deposits. Potential pyroclastic deposits were generally found in settings similar to previously identified deposits, including areas within or near mare deposits adjacent to highlands, within floor-fractured craters, and along fissures in mare deposits. However, a significant new finding is the discovery of localized pyroclastic deposits within floor-fractured craters Anderson E and F on the lunar farside, isolated from other known similar deposits. Our search confirms that most major regional and localized low-albedo pyroclastic deposits have been identified on the Moon down to ~100 m/pix resolution, and that additional newly identified deposits are likely to be either isolated small deposits or additional portions of discontinuous, patchy deposits.

Mass Median Plume Angle: A novel approach to characterize plume geometry in solution based pMDIs.

PubMed

Moraga-Espinoza, Daniel; Eshaghian, Eli; Smyth, Hugh D C

2018-05-30

High-speed laser imaging (HSLI) is the preferred technique to characterize the geometry of the plume in pressurized metered dose inhalers (pMDIs). However, current methods do not allow for simulation of inhalation airflow and do not use drug mass quantification to determine plume angles. To address these limitations, a Plume Induction Port Evaluator (PIPE) was designed to characterize the plume geometry based on mass deposition patterns. The method is easily adaptable to current pMDI characterization methodologies, uses similar calculations methods, and can be used under airflow. The effect of airflow and formulation on the plume geometry were evaluated using PIPE and HSLI. Deposition patterns in PIPE were highly reproducible and log-normal distributed. Mass Median Plume Angle (MMPA) was a new characterization parameter to describe the effective angle of the droplets deposited in the induction port. Plume angles determined by mass showed a significant decrease in size as ethanol increases which correlates to the decrease on vapor pressure in the formulation. Additionally, airflow significantly decreased the angle of the plumes when cascade impactor was operated under flow. PIPE is an alternative to laser-based characterization methods to evaluate the plume angle of pMDIs based on reliable drug quantification while simulating patient inhalation. Copyright © 2018. Published by Elsevier B.V.

Students' Use of Asynchronous Discussions for Academic Discourse Socialization

ERIC Educational Resources Information Center

Beckett, Gulbahar H.; Amaro-Jimenez, Carla; Beckett, Kelvin S.

2010-01-01

Our universities are becoming increasingly diverse at the same time as online asynchronous discussions (OADs) are emerging as the most important forum for computer mediated communication (CMC) in distance education. But there is shortage of studies that explore how graduate students from different ethnic, linguistic and cultural backgrounds use…

Soil-like deposits observed by Sojourner, the Pathfinder rover

USGS Publications Warehouse

Moore, Henry J.; Bickler, Donald B.; Crisp, Joy A.; Eisen, Howard J.; Gensler, Jeffrey A.; Haldemann, Albert F.C.; Matijevic, Jacob R.; Reid, Lisa K.; Pavlics, Ferenc

1999-01-01

Most of the soil-like materials at the Pathfinder landing site behave like moderately dense soils on Earth with friction angles near 34°-39° and are called cloddy deposits. Cloddy deposits appear to be poorly sorted with dust-sized to granule-sized mineral or rock grains; they may contain pebbles, small rock fragments, and clods. Thin deposits of porous, compressible drifts with friction angles near 26°-28° are also present. Drifts are fine grained. Cohesions of both types of deposits are small. There may be indurated soil-like deposits and/or coated or crusted rocks. Cloddy deposits may be fluvial sediments of the Ares-Tiu floods, but other origins, such as ejecta from nearby impact craters, should be considered. Drifts are probably dusts that settled from the Martian atmosphere. Remote-sensing signatures of the deposits inferred from rover observations are consistent with those observed from orbit and Earth.

Omnidirectional anti-reflection properties of vertically align SiO2 nanorod films prepared by electron beam evaporation with glancing angle deposition

NASA Astrophysics Data System (ADS)

Prachachet, R.; Samransuksamer, B.; Horprathum, M.; Eiamchai, P.; Limwichean, S.; Chananonnawathorn, C.; Lertvanithphol, T.; Muthitamongkol, P.; Boonruang, S.; Buranasiri, P.

2018-03-01

Omnidirectional anti-reflection coating nanostructure film have attracted enormous attention for the developments of the optical coating, lenses, light emitting diode, display and photovoltaic. However, fabricated of the omnidirectional antireflection nanostructure film on glass substrate in large area was a challenge topic. In the past two decades, the invention of glancing angle deposition technique as a growth of well-controlled two and three-dimensional morphologies has gained significant attention because of it is simple, fast, cost-effective and high mass production capability. In this present work, the omnidirectional anti-reflection nanostructure coating namely silicon dioxide (SiO2) nanorods has been investigated for optimized high transparent layer at all light incident angle. The SiO2 nanorod films of an optimally low refractive index have been fabricated by electron beam evaporation with the glancing angle deposition technique. The morphological of the prepared sampled were characterized by field-emission scanning electron microscope (FE-SEM) and high-resolution transmission electron microscope (HRTEM). The optical transmission and omnidirectional property of the SiO2 nanorod films were investigated by UV-Vis-NIR spectrophotometer. The measurement were performed at normal incident angle and a full spectral range of 200 - 2000 nm. The angle dependent transmission measure were investigated by rotating the specimen, with incidence angle defined relative to the surface normal of the prepared samples. The morphological characterization results showed that when the glancing angle deposition technique was applied, the vertically align SiO2 nanorods with partially isolated columnar structure can be constructed due to the enhanced shadowing and limited addtom diffusion effect. The average transmission of the vertically align SiO2 nanorods were higher than the glass substrate reference sample over the visible wavelength range at all incident angle due to the transition in the refractive index profile from air to the nanostructure layer that improved the anti-reflection characteristics.

Morphology and crystallinity of ZnS nanocolumns prepared by glancing angle deposition.

PubMed

Lu, Lifang; Zhang, Fujun; Xu, Zheng; Zhao, Suling; Wang, Yongsheng

2010-03-01

ZnS films with different morphologies and nanometer structures were fabricated via high vacuum electron beam deposition by changing the oblique angle alpha between the incoming particle flux and the substrate normal. The morphology and crystallinity of ZnS nanocrystalline films prepared on the substrates at alpha = 0 degrees and 80 degrees were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray diffraction. These experimental results show that the ZnS nanocolumn structure was formed at the situation of alpha = 80 degrees. The incidence angle also strongly influenced the crystallinity of thin films. The most intensive diffraction peaks changed from (220) to (111) when the incidence angle was set to 0 degrees and 80 degrees. The dynamic growth process of ZnS films at alpha = 0 degrees and 80 degrees has been analyzed by shadow effect and atomic surface diffusion. The transmittance spectra of the ZnS thin films prepared at different oblique angles were measured, and the transmissivity of ZnS nanocolumn thin films was enhanced compared with ZnS thin films prepared by normal deposition in the visible light range.

The path for long range conduction in high J(sub c) TlBa2Ca2Cu3O(8+x) spray-pyrolyzed deposits

NASA Astrophysics Data System (ADS)

Kroeger, D. M.; Goyal, A.; Specht, E. D.; Wang, Z. L.; Tkaczyk, J. E.; Sutliff, J. A.; Deluca, J. A.

Grain boundary misorientations and local texture in polycrystalline TlBa2Ca2Cu3O(8+x) deposits prepared by thallination of spray-pyrolyzed precursor deposits on yttria-stabilized zirconia have been determined from transmission electron microscopy, electron backscatter diffraction patterns, and x ray diffraction. The deposits were polycrystalline, had small grains, and excellent c-axis alignment. The deposits contained colonies of grains with similar but not identical a-axis orientations. Most grain boundaries within a colony have small misorientation angles and should not be weak links. It is proposed that long range current flow occurs through a percolative network of small angle grain boundaries at colony intersections.

Microstructural Effects and Properties of Non-line-of-Sight Coating Processing via Plasma Spray-Physical Vapor Deposition

NASA Astrophysics Data System (ADS)

Harder, Bryan J.; Zhu, Dongming; Schmitt, Michael P.; Wolfe, Douglas E.

2017-08-01

Plasma spray-physical vapor deposition (PS-PVD) is a unique processing method that bridges the gap between conventional thermal spray and vapor phase methods, and enables highly tailorable coatings composed of a variety of materials in thin, dense layers or columnar microstructures with modification of the processing conditions. The strengths of this processing technique are material and microstructural flexibility, deposition speed, and potential for non-line-of-sight (NLOS) capability by vaporization of the feedstock material. The NLOS capability of PS-PVD is investigated here using yttria-stabilized zirconia and gadolinium zirconate, which are materials of interest for turbine engine applications. PS-PVD coatings were applied to static cylindrical substrates approximately 6-19 mm in diameter to study the coating morphology as a function of angle. In addition, coatings were deposited on flat substrates under various impingement configurations. Impingement angle had significant effects on the deposition mode, and microscopy of coatings indicated that there was a shift in the deposition mode at approximately 90° from incidence on the cylindrical samples, which may indicate the onset of more turbulent flow and PVD-like growth. Coatings deposited at non-perpendicular angles exhibited a higher density and nearly a 2× improvement in erosion performance when compared to coatings deposited with the torch normal to the surface.

Superhydrophobic hybrid inorganic-organic thiol-ene surfaces fabricated via spray-deposition and photopolymerization.

PubMed

Sparks, Bradley J; Hoff, Ethan F T; Xiong, Li; Goetz, James T; Patton, Derek L

2013-03-13

We report a simple and versatile method for the fabrication of superhydrophobic inorganic-organic thiol-ene coatings via sequential spray-deposition and photopolymerization under ambient conditions. The coatings are obtained by spray-deposition of UV-curable hybrid inorganic-organic thiol-ene resins consisting of pentaerythritol tetra(3-mercaptopropionate) (PETMP), triallyl isocyanurate (TTT), 2,4,6,8-tetramethyl-2,4,6,8-tetravinylcyclotetrasiloxane (TMTVSi), and hydrophobic fumed silica nanoparticles. The spray-deposition process and nanoparticle agglomeration/dispersion provide surfaces with hierarchical morphologies exhibiting both micro- and nanoscale roughness. The wetting behavior, dependent on the concentration of TMTVSi and hydrophobic silica nanoparticles, can be varied over a broad range to ultimately provide coatings with high static water contact angles (>150°), low contact angle hysteresis, and low roll off angles (<5°). The cross-linked thiol-ene coatings are solvent resistant, stable at low and high pH, and maintain superhydrophobic wetting behavior after extended exposure to elevated temperatures. We demonstrate the versatility of the spray-deposition and UV-cure process on a variety of substrate surfaces including glass, paper, stone, and cotton fabric.

Phase field kinetics of lithium electrodeposits

NASA Astrophysics Data System (ADS)

Ely, David R.; Jana, Aniruddha; García, R. Edwin

2014-12-01

A phase field description is formulated to describe the growth kinetics of an heterogeneously nucleated distribution of lithium electrodeposits. The underlying variational principle includes the bulk electrochemical contributions to the free energy of transformation of the system, the electrolyte-dendrite interfacial energy, and the substrate work of adhesion energetics. Results demonstrate that the rate of electrodeposition at the tip of an isolated dendrite is higher than the rate corresponding to the average overpotential, while the back contact is electrochemically shielded, thus favoring elongated, needle-like shapes. For large populations of electrochemically interacting deposits, two spatially distinct regions of behavior develop: one directly facing the counter-electrode where the local surficial electrodeposition dominates the local kinetics; and a second region, in the vicinity of the substrate-deposit interface, where the electrochemical shielding induced by the tip enables lateral electrochemical lithium exchange dendrite coalescence for small contact angle deposits, and dendrite dewetting and electrodissolution for large contact angle deposits. The underlying physical mechanisms through which some lithium nuclei detach from the depositing substrate, self-induce electrodissolution, while other continue to grow and coalesce are described for different contact angles.

Wettability of modified silica layers deposited on glass support activated by plasma

NASA Astrophysics Data System (ADS)

Terpiłowski, Konrad; Rymuszka, Diana; Goncharuk, Olena V.; Sulym, Iryna Ya.; Gun'ko, Vladimir M.

2015-10-01

Fumed silica modified by hexamethyldisilazane [HDMS] and polydimethylsiloxane [PDMS] was dispersed in a polystyrene/chloroform solution. To increase adhesion between deposited silica layers and a glass surface, the latter was pretreated with air plasma for 30 s. The silica/polystyrene dispersion was deposited on the glass support using a spin coater. After deposition, the plates were dried in a desiccator for 24 h. Water advancing and receding contact angles were measured using the tilted plate method. The apparent surface free energy (γS) was evaluated using the contact angle hysteresis approach. The surface topography was determined using the optical profilometry method. Contact angles changed from 59.7° ± 4.4 (at surface coverage with trimethylsilyl groups Θ = 0.14) to 155° ± 3.1 at Θ = 1. The value of γS decreased from 51.3 ± 2.8 mJ/m2 (for the sample at the lowest value of Θ) to 1.0 ± 0.4 mJ/m2 for the most hydrophobic sample. Thus, some systems with a high degree of modification by HDMS showed superhydrophobicity, and the sliding angle amounted to about 16° ± 2.1.

Fabrication of Ultra-thin Color Films with Highly Absorbing Media Using Oblique Angle Deposition.

PubMed

Yoo, Young Jin; Lee, Gil Ju; Jang, Kyung-In; Song, Young Min

2017-08-29

Ultra-thin film structures have been studied extensively for use as optical coatings, but performance and fabrication challenges remain.  We present an advanced method for fabricating ultra-thin color films with improved characteristics. The proposed process addresses several fabrication issues, including large area processing. Specifically, the protocol describes a process for fabricating ultra-thin color films using an electron beam evaporator for oblique angle deposition of germanium (Ge) and gold (Au) on silicon (Si) substrates.  Film porosity produced by the oblique angle deposition induces color changes in the ultra-thin film. The degree of color change depends on factors such as deposition angle and film thickness. Fabricated samples of the ultra-thin color films showed improved color tunability and color purity. In addition, the measured reflectance of the fabricated samples was converted into chromatic values and analyzed in terms of color. Our ultra-thin film fabricating method is expected to be used for various ultra-thin film applications such as flexible color electrodes, thin film solar cells, and optical filters. Also, the process developed here for analyzing the color of the fabricated samples is broadly useful for studying various color structures.

Centre d'Observacio de l'Univers: first year of activities

NASA Astrophysics Data System (ADS)

Ribas, S. J.

2011-11-01

The Centre d'Observacio de l'Univers is one of the parts of the Parc Astronomic Montsec (PAM). PAM is an initiative of the Catalan government, through the Consorci del Montsec (Montsec Consortium), to take advantage of the capabilities and potential of the Montsec region to develop scientific research, training, and outreach activities, particularly in the field of astronomy. The choice of the Montsec mountains to install the PAM was motivated by the magnificent conditions for observing the sky at night; the sky above Montsec is the best (natural sky free of light pollution) in Catalonia for astronomical observations. The PAM has two main parts: the Observatori Astronomic del Montsec (OAdM) and the Centre d'Observacio del'Univers (COU). The OAdM is a professional observatory with an 80 cm catadioptric telescope (Joan Oro Telescope). The COU is a large multipurpose center which is intended to become an educational benchmark for teaching and communicate astronomy and other sciences in Catalonia. Since the opening more than 50000 visitors went to this center to enjoy science with Montsec dark skies and an special natural environment.

A reticle retrofit and dosimetric consideration for a linear accelerator.

PubMed

Krithivas, V

1996-01-01

An imperfect reticle system in an accelerator causes uncertainties in source-skin distance (SSD), off-axis distance (OAD), isocenter, and so forth. A reticle was designed and fabricated, and its implications on x-ray and electron beam dosimetry were investigated. A new reticle frame was dimensioned to fit snugly in the accelerator. The frame was fabricated to carry a pair of adjustable cross wires and to allow the machine operation in the photon and electron modes. The impact of the cross wires on 6 MV photon and 5-10 MeV electron beam parameters such as dose rate (Gy/monitor unit), beam uniformity, surface dose, and so forth, were studied using suitable ion chambers and phantoms. The retrofitted system offered long-term mechanical stability leading to precise SSD, OAD, and isocenter measurements. Changes introduced by the cross wires on the 6 MV photon and 5-10 MeV electron beams are presented. Long-term stability of a reticle in an accelerator is important for an accurate patient setup and for making reliable dosimetric measurements. Beam characteristrics have to be studied whenever modifications on a reticle system are made.

Investigation on the interfacial chemical state and band alignment for the sputtering-deposited CaF2/p-GaN heterojunction by angle-resolved X-ray photoelectron spectroscopy

NASA Astrophysics Data System (ADS)

Zhang, Kexiong; Liao, Meiyong; Sumiya, Masatomo; Koide, Yasuo; Sang, Liwen

2016-11-01

The interfacial chemical state and the band alignment of the sputtering-deposited CaF2/p-GaN hetero-structure were investigated by angle-resolved X-ray photoelectron spectroscopy. The dependence of Ga 3p core-level positions on the collection angles proves that the downward band bending of p-GaN is reduced from 1.51 to 0.85 eV after the deposition of CaF2, which may be due to the reduction of Mg-Ga-O-related interface states by the oxygen-free deposition of CaF2. The band gap of sputtering-deposited CaF2 is estimated to be about 7.97 eV with a potential gradient of 0.48 eV obtained by the variation of the Ca 2p3/2 position on different collection angles. By taking into account the p-GaN surface band bending and potential gradient in the CaF2 layer, large valence and conduction band offsets of 2.66 ± 0.20 and 1.92 ± 0.20 eV between CaF2 and p-GaN are obtained. These results indicate that CaF2 is a promising gate dielectric layer on the p-GaN for the application of metal-insulator-semiconductor devices.

Superhydrophobicity of hierarchical nanostructure of candle soot films

NASA Astrophysics Data System (ADS)

Hankhuntond, A.; Singjai, P.; Sakulsermsuk, S.

2017-09-01

Candle soot containing carbon nanoparticles can form hierarchical structure films. We prepared soot films by using glass slides blocking candle flame in the middle of the flame. The hierarchical nanostructures of the carbon nanoparticles films were confirmed by scanning electron microscopy and transmission electron microscopy. Carbon nanoparticle size was 49.2 ± 9.0 nm from SEM, which agrees to 37.9 ± 8.5 nm from TEM. The contact angles of water droplets on these films are more than 150°, indicating superhydrophobic surface. Decrease contact angles of water droplets were observed with an increase deposition time. The decrease of contact angle was saturated at about 150° when the deposition time reaches 180 s. Cassie-Baxter state was attributed to describe superhydrophobicity of carbon nanoparticles films because the hierarchical nanostructures of the surface provide a large fraction of hollows on the surface. We proposed that the contact angle dependence on deposition time was governed by the increase of the distance between nanopillars in carbon nanoparticles films.

Experimental Study of the Angle of Repose of Surrogate Martian Dust

NASA Technical Reports Server (NTRS)

Moeller, L. E.; Tuller, M.; Baker, L.; Marshall, J.; Castiglione, P.; Kuhlman, K.

2003-01-01

Accumulation of wind-blown dust particles on solar cells and instruments will be a great challenge in the exploration of Mars, significantly reducing their lifetime, durability, and power output. For future Mars Lander missions it is crucial to gain information about the ideal angle at which solar panels can be positioned to minimize dust deposition and thus, maximize the power output and lifetime of the solar cells. The major determinant for the optimal panel angle is the angle of repose of the dust particles that is dependent on a variety of physical and chemical properties of the particles, the panel surface, and the environmental conditions on the Mars surface. To gain a basic understanding of the physical and chemical processes that govern dust deposition and to get feedback for the design of an experiment suitable for one of the future Mars Lander missions we simulate atmospheric conditions expected on the Mars surface in a controlled chamber, and observe the angle of repose of Mars dust surrogates. Dust deposition and angle of repose were observed on different sized spheres. To cover a range of potential materials we will use spheres made of 7075 aluminum (10 mm, and 15 mm), alumina oxide ceramic (10 mm), and Teflon(trademark) (10 mm) and wafers of gallium arsenide, silicon.

Diabetes mellitus with Laron syndrome: case report.

PubMed

Agladıoglu, Sebahat Yılmaz; Cetınkaya, Semra; Savas Erdeve, Senay; Onder, Asan; Kendırcı, Havva Nur Peltek; Bas, Veysel Nijat; Aycan, Zehra

2013-01-01

There are different opinions concerning changes in glucose metabolism in patients with Laron syndrome. In this paper we discuss the treatment results of our patient with Laron syndrome who developed diabetes during late adolescence. A 19-year-old boy with Laron syndrome was referred to our clinic for follow-up. He had been diagnosed with Laron syndrome (LS) at 4 years old and rIGF-1 therapy was initiated. After 4 months the treatment was discontinued. At the age of 17, rIGF-1 therapy was restarted. A height gain of 8.8 cm. was observed during the 2-year treatment period. He was admitted to our hospital at the age of 19 years following discontinuation of the therapy. At that time, his height was 142 cm, and weight for height was 136%. His blood glucose was 85 mg/dL (4.72 mmol/L), insulin was 26.39 pmol/L, and HbA1c was 5.4%. At the age of 20, when he has not been receiving IGF-1 therapy for 1 year, his weight for height was 143 cm. Laboratory evaluation revealed that fasting blood glucose was 176 mg/dL (9.77 mmol/L), fasting insulin was 29.86 pmol/L, and HbA1c was 7.5%. Primary insulin therapy was then initiated. His parents both had a diagnosis of type 2 diabetes. Insulin therapy was switched to oral antidiabetic (OAD) therapy at the end of the second year because of a normal C-peptide level of 0.8 nmol/L under insulin therapy. After 6 months of OAD, HbA1c was 5.7%. The treatment was then switched to IGF-1 therapy, but his blood glucose profile was impaired and OAD therapy was restarted. In conclusion, we observed that genetic susceptibility and abdominal obesity caused type 2 diabetes in this patient. We believe that oral antidiabetic agents and life-style changes may be the appropriate approach when diabetes is developed in LS patients.

SU-E-T-339: Dosimetric Verification of Acuros XB Dose Calculation Algorithm On An Air Cavity for 6-MV Flattening Filter-Free Beam

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kang, S; Suh, T; Chung, J

Purpose: This study was to verify the accuracy of Acuros XB (AXB) dose calculation algorithm on an air cavity for a single radiation field using 6-MV flattening filter-free (FFF) beam. Methods: A rectangular slab phantom containing an air cavity was made for this study. The CT images of the phantom for dose calculation were scanned with and without film at measurement depths (4.5, 5.5, 6.5 and 7.5 cm). The central axis doses (CADs) and the off-axis doses (OADs) were measured by film and calculated with Analytical Anisotropic Algorithm (AAA) and AXB for field sizes ranging from 2 Χ 2 tomore » 5 Χ 5 cm{sup 2} of 6-MV FFF beams. Both algorithms were divided into AXB-w and AAA -w when included the film in phantom for dose calculation, and AXB-w/o and AAA-w/o in calculation without film. The calculated OADs for both algorithms were compared with the measured OADs and difference values were determined using root means squares error (RMSE) and gamma evaluation. Results: The percentage differences (%Diffs) between the measured and calculated CAD for AXB-w was most agreement than others. Compared to the %Diff with and without film, the %Diffs with film were decreased than without within both algorithms. The %Diffs for both algorithms were reduced with increasing field size and increased relative to the depth increment. RMSEs of CAD for AXB-w were within 10.32% for both inner-profile and penumbra, while the corresponding values of AAA-w appeared to 96.50%. Conclusion: This study demonstrated that the dose calculation with AXB within air cavity shows more accurate than with AAA compared to the measured dose. Furthermore, we found that the AXB-w was superior to AXB-w/o in this region when compared against the measurements.« less

Dark Skies Africa: an NOAO and IAU OAD Program on Light Pollution

NASA Astrophysics Data System (ADS)

Walker, Constance E.; Tellez, D.; Pompea, S. M.

2014-01-01

The IAU’s Office of Astronomy for Development (OAD) awarded the National Optical Astronomy Observatory (NOAO) with a grant to deliver a “Dark Skies Outreach to Sub-Saharan Africa” program to institutions in 12 African countries during 2013. The program helped students identify wasteful and inefficient lighting and provided ways to reduce consumption and to keep energy costs in check. The goal was to inspire students to be responsible stewards in helping their community safeguard one of Africa’s natural resources - a dark night sky. Thirteen kits made by the NOAO Education and Public Outreach group were sent to coordinators at university, science center and planetarium-type institutions in 12 African countries and to the IAU OAD. The program’s kit included complete instructional guides and supplies for six activities and a project on energy conservation and responsible lighting. The six activities were taught to the coordinators in a series of six Google+ Hangout sessions scheduled from June to mid-November. The coordinators at the institutions in the twelve countries in turn trained local teachers in junior and senior high schools. The Google+ Hangout sessions also included instruction on carrying out evaluations. From the end of November until mid-December students from the different African countries shared final class projects (such as posters or powerpoints) on the program’s website. The entire program was designed to help coordinators and educators work with students, parents and the community to identify dark sky resource, lighting and energy issues and to assess their status, efficiency and effectiveness. Participants will take away from the presentation new techniques on using Google+ Hangout sessions to instruct and sustain a community of coordinators and educators through distance learning as well as immersing them (and their students) in Project Based Learning after a scaffolded sequence of activities.

Postauthorization safety study of the DPP-4 inhibitor saxagliptin: a large-scale multinational family of cohort studies of five outcomes

PubMed Central

Carbonari, Dena M; Saine, M Elle; Newcomb, Craig W; Roy, Jason A; Liu, Qing; Wu, Qufei; Cardillo, Serena; Haynes, Kevin; Kimmel, Stephen E; Reese, Peter P; Margolis, David J; Apter, Andrea J; Reddy, K Rajender; Hennessy, Sean; Bhullar, Harshvinder; Gallagher, Arlene M; Esposito, Daina B; Strom, Brian L

2017-01-01

Objective To evaluate the risk of serious adverse events among patients with type 2 diabetes mellitus initiating saxagliptin compared with oral antidiabetic drugs (OADs) in classes other than dipeptidyl peptidase-4 (DPP-4) inhibitors. Research design and methods Cohort studies using 2009–2014 data from two UK medical record data sources (Clinical Practice Research Datalink, The Health Improvement Network) and two USA claims-based data sources (HealthCore Integrated Research Database, Medicare). All eligible adult patients newly prescribed saxagliptin (n=110 740) and random samples of up to 10 matched initiators of non-DPP-4 inhibitor OADs within each data source were selected (n=913 384). Outcomes were hospitalized major adverse cardiovascular events (MACE), acute kidney injury (AKI), acute liver failure (ALF), infections, and severe hypersensitivity events, evaluated using diagnostic coding algorithms and medical records. Cox regression was used to determine HRs with 95% CIs for each outcome. Meta-analyses across data sources were performed for each outcome as feasible. Results There were no increased incidence rates or risk of MACE, AKI, ALF, infection, or severe hypersensitivity reactions among saxagliptin initiators compared with other OAD initiators within any data source. Meta-analyses demonstrated a reduced risk of hospitalization/death from MACE (HR 0.91, 95% CI 0.85 to 0.97) and no increased risk of hospitalization for infection (HR 0.97, 95% CI 0.93 to 1.02) or AKI (HR 0.99, 95% CI 0.88 to 1.11) associated with saxagliptin initiation. ALF and hypersensitivity events were too rare to permit meta-analysis. Conclusions Saxagliptin initiation was not associated with increased risk of MACE, infection, AKI, ALF, or severe hypersensitivity reactions in clinical practice settings. Trial registration number NCT01086280, NCT01086293, NCT01086319, NCT01086306, and NCT01377935; Results. PMID:28878934

Comparative effectiveness of vildagliptin in combination with other oral anti-diabetes agents in usual-care conditions: the EDGE-Latin America study.

PubMed

Mendivil, Carlos O; Márquez-Rodríguez, Eduardo; Angel, Iván D; Paz, Gustavo; Rodríguez, Cruz; Almada, Jorge; Szyskowsky, Ofelia

2014-09-01

To assess the proportion of patients on vildagliptin add-on dual therapy who respond to treatment over a 12 month follow-up, relative to comparator oral anti-diabetes dual therapy, in a usual care setting. Participants were patients with type 2 diabetes (T2DM) aged 18 years and older from 311 centers in Argentina, Colombia, Ecuador, Mexico and Venezuela. Patients were taking monotherapy with an oral anti-diabetes drug (OAD), and were prescribed a new add-on OAD based on the judgment of their personal physician. According to this choice, patients were assigned to one of the two cohorts: vildagliptin or comparator OADs. The primary endpoint was the proportion of patients achieving an A1c drop >0.3% without edema, hypoglycemia, weight gain or discontinuation due to gastrointestinal (GI) events. The secondary endpoint was the proportion of patients with baseline A1c ≥7% who reached the goal of an A1c <7% without hypoglycemia or weight gain. The per-protocol population (a subset of the intention-to-treat population that excluded patients with pre-specified protocol deviations) comprised 3773 patients, 3002 in the vildagliptin cohort and 771 in the comparator cohort. The proportion of patients reaching the primary endpoint was higher in the vildagliptin cohort (60.3%) than the comparator cohort (50.7%), OR 1.48 (95% CI: 1.25-1.73). The same was observed for the secondary endpoint (44.8 versus 33.1%) OR 1.64 (95% CI: 1.37-1.98). The incidence of adverse events was low and similar between treatment cohorts. In a usual care setting, patients treated with a vildagliptin combination succeeded in lowering A1c to <7%, without weight gain, hypoglycemia or peripheral edema more often than patients treated with comparator combinations, without increased risk of adverse events. Key limitations are the observational nature of the study and its relatively limited 12 month timeframe.

Uptake of CO2, SO2, HNO3 and HCl on calcite (CaCO3) at 300 K: mechanism and the role of adsorbed water.

PubMed

Santschi, Ch; Rossi, M J

2006-06-01

All experimental observations of the uptake of the four title compounds on calcite are consistent with the presence of a reactive bifunctional surface intermediate Ca(OH)(HCO3) that has been proposed in the literature. The uptake of CO2 and SO2 occurs on specific adsorption sites of crystalline CaCO3(s) rather than by dissolution in adsorbed water, H2O(ads). SO2 primarily interacts with the bicarbonate moiety whereas CO2, HNO3 and HCl all react first with the hydroxyl group of the surface intermediate. Subsequently, the latter two react with the bicarbonate group to presumably form Ca(NO3)2 and CaCl2.2H2O. The effective equilibrium constant of the interaction of CO2 with calcite in the presence of H2O(ads) is kappa = deltaCO2/(H2O(ads)[CO2]) = 1.62 x 10(3) bar(-1), where CO2 is the quantity of CO2 adsorbed on CaCO3. The reaction mechanism involves a weakly bound precursor species that is reversibly adsorbed and undergoes rate-controlling concurrent reactions with both functionalities of the surface intermediate. The initial uptake coefficients gamma0 on calcite powder depend on the abundance of H2O(ads) under the present experimental conditions and are on the order of 10(-4) for CO2 and 0.1 for SO2, HNO3 and HCl, with gamma(ss) being significantly smaller than gamma0 for HNO3 and HCl, thus indicating partial saturation of the uptake. At 33% relative humidity and 300 K there are 3.5 layers of H2O adsorbed on calcite that reduce to a fraction of a monolayer of weakly and strongly bound water upon pumping and/or heating.

The investigation of the efficacy of insulin glargine on glycemic control when combined with either repaglinide or acarbose in obese Type 2 diabetic patients.

PubMed

Duran, C; Tuncel, E; Ersoy, C; Ercan, I; Selimoglu, H; Kiyici, S; Guclu, M; Erturk, E; Imamoglu, S

2009-01-01

Combinations of insulin and oral antidiabetic drugs (OAD) are often prescribed instead of insulin alone. In this study, the effects of insulin glargine (IG) in combination with repaglinide or acarbose on glycemic parameters were investigated. Obese Type 2 diabetic patients with fasting blood glucose (FBG) levels >or= 7.7 mmol/l [corrected] and hemoglobin glycated (A1C) >or=9% under maximal OAD combination therapy were enrolled. Previous therapies were discontinued, and patients were randomized into 2 groups. The combinations of IG and repaglinide were administered to group 1, and of IG and acarbose to group 2 for 13 weeks. Twenty patients in group 1 and 18 patients in group 2 completed the study. A1C levels were significantly decreased from 10.9+/-1.4% to 7.7+/-1.1% in group 1 and 11.0+/-1.4% to 8.1+/-1.4% in group 2. FBG levels were significantly decreased from 11.9+/-2.7 to 7.1+/-2.3 mmol/l in group 1 and 11.1+/-2.5 to 6.8+/-1.4 mmol/l in group 2. Post-prandial glucose levels were significantly decreased from 15.3+/-3.8 to 10.3+/-3.0 mmol/l in group 1 and 14.0+/-3.1 to 8.9+/-2.2 mmol/l in group 2. Intergroup comparisons indicated no significant differences. More weight gain was detected in group 1, compared to the baseline. Symptomatic hypoglycemia incidence was similar in both groups. Severe hypoglycemic attacks were seen in two patients in group 1. Flatulence incidence was higher in acarbose group. Conclusively, repaglinide and acarbose were equally effective when combined with IG for obese Type 2 diabetic patients controlled inadequately with OAD alone. Furthermore, acarbose seems to have advantages over repaglinide concerning weight gain and severe hypoglycemic attacks.

Fabrication of Ni-silicide/Si heterostructured nanowire arrays by glancing angle deposition and solid state reaction.

PubMed

Hsu, Hsun-Feng; Huang, Wan-Ru; Chen, Ting-Hsuan; Wu, Hwang-Yuan; Chen, Chun-An

2013-05-10

This work develops a method for growing Ni-silicide/Si heterostructured nanowire arrays by glancing angle Ni deposition and solid state reaction on ordered Si nanowire arrays. Samples of ordered Si nanowire arrays were fabricated by nanosphere lithography and metal-induced catalytic etching. Glancing angle Ni deposition deposited Ni only on the top of Si nanowires. When the annealing temperature was 500°C, a Ni3Si2 phase was formed at the apex of the nanowires. The phase of silicide at the Ni-silicide/Si interface depended on the diameter of the Si nanowires, such that epitaxial NiSi2 with a {111} facet was formed at the Ni-silicide/Si interface in Si nanowires with large diameter, and NiSi was formed in Si nanowires with small diameter. A mechanism that is based on flux divergence and a nucleation-limited reaction is proposed to explain this phenomenon of size-dependent phase formation.

Fabrication of Ni-silicide/Si heterostructured nanowire arrays by glancing angle deposition and solid state reaction

PubMed Central

2013-01-01

This work develops a method for growing Ni-silicide/Si heterostructured nanowire arrays by glancing angle Ni deposition and solid state reaction on ordered Si nanowire arrays. Samples of ordered Si nanowire arrays were fabricated by nanosphere lithography and metal-induced catalytic etching. Glancing angle Ni deposition deposited Ni only on the top of Si nanowires. When the annealing temperature was 500°C, a Ni3Si2 phase was formed at the apex of the nanowires. The phase of silicide at the Ni-silicide/Si interface depended on the diameter of the Si nanowires, such that epitaxial NiSi2 with a {111} facet was formed at the Ni-silicide/Si interface in Si nanowires with large diameter, and NiSi was formed in Si nanowires with small diameter. A mechanism that is based on flux divergence and a nucleation-limited reaction is proposed to explain this phenomenon of size-dependent phase formation. PMID:23663726

Development of an angle-scanning spectropolarimeter: Preliminary results

NASA Astrophysics Data System (ADS)

Nouri, Sahar A.; Gregory, Don A.; Fuller, Kirk

2018-02-01

A fixed-angle spectropolarimeter capable of measuring the Mueller matrix of particle deposits and conventional optical elements over the 300-1100 nm spectral range has been built, calibrated and extensively tested. A second generation of this instrument is being built which can scan from 0° to near 180° in both scattering angle and sample orientation, enabling studies of the bidirectional Mueller matrices of nanoparticle arrays, atmospheric aerosol deposits, and nano- and microstructured surfaces. This system will also provide a much needed metrology capability for fully characterizing the performance of optical devices and device components from the near-infrared through the medium wave ultraviolet. Experimental results taken using the first generation fixed-angle arrangement will be presented along with the rationale for building the second.

Highly Sensitive H2S Sensor Based on the Metal-Catalyzed SnO2 Nanocolumns Fabricated by Glancing Angle Deposition

PubMed Central

Yoo, Kwang Soo; Han, Soo Deok; Moon, Hi Gyu; Yoon, Seok-Jin; Kang, Chong-Yun

2015-01-01

As highly sensitive H2S gas sensors, Au- and Ag-catalyzed SnO2 thin films with morphology-controlled nanostructures were fabricated by using e-beam evaporation in combination with the glancing angle deposition (GAD) technique. After annealing at 500 °C for 40 h, the sensors showed a polycrystalline phase with a porous, tilted columnar nanostructure. The gas sensitivities (S = Rgas/Rair) of Au and Ag-catalyzed SnO2 sensors fabricated by the GAD process were 0.009 and 0.015, respectively, under 5 ppm H2S at 300 °C, and the 90% response time was approximately 5 s. These sensors showed excellent sensitivities compared with the SnO2 thin film sensors that were deposited normally (glancing angle = 0°, S = 0.48). PMID:26134105

Morphogenesis of nanostructures in glancing angle deposition of metal thin film coatings

NASA Astrophysics Data System (ADS)

Brown, Timothy James

Atomic vapors condensed onto solid surfaces form a remarkable category of condensed matter materials, the so-called thin films, with a myriad of compositions, morphological structures, and properties. The dynamic process of atomic condensation exhibits self-assembled pattern formation, producing morphologies with atomic-scale three- dimensional structures of seemingly limitless variety. This study attempts to shed new light on the dynamical growth processes of thin film deposition by analyzing in detail a previously unreported specific distinct emergent structure, a crystalline triangular-shaped spike that grows within copper and silver thin films. I explored the deposition parameters that lead to the growth of these unique structures, referred to as "nanospikes", fabricating approximately 55 thin films and used scanning electron microscopy and x-ray diffraction analysis. The variation of parameters include: vapor incidence angle, film thickness, substrate temperature, deposition rate, deposition material, substrate, and source-to-substrate distance. Microscopy analysis reveals that the silver and copper films deposited at glancing vapor incidence angles, 80 degrees and greater, have a high degree of branching interconnectivity between adjacent inclined nanorods. Diffraction analysis reveals that the vapor incidence angle influences the sub-populations of crystallites in the films, producing two different [110] crystal texture orientations. I hypothesize that the growth of nanospikes from nanorods is initiated by the stochastic arrival of vapor atoms and photons emitted from the deposition source at small diameter nanorods, and then driven by localized heating from vapor condensation and photon absorption. Restricted heat flow due to nanoscale thermal conduction maintains an elevated local temperature at the nanorod, enhancing adatom diffusion and enabling fast epitaxial crystal growth, leading to the formation and growth of nanospikes. Electron microscopy and x-ray diffraction analysis, and comparisons to related scientific literature, support this hypothesis. I also designed a highly modular ultrahigh vacuum deposition chamber, capable of concurrently mounting several different pieces of deposition equipment, that allows for a high degree of control of the growth dynamics of deposited thin films. I used the newly designed chamber to fabricate tailor-made nanostructured tantalum films for use in ultracapacitors, for the Cabot Corporation.

Local texture and strongly linked conduction in spray-pyrolyzed TlBa2Ca2Cu3O(8+x) deposits

NASA Astrophysics Data System (ADS)

Kroeger, D. M.; Goyal, A.; Specht, E. D.; Wang, Z. L.; Tkaczyk, J. E.; Sutliff, J. A.; Deluca, J. A.

Local texture in polycrystalline TlBa2Ca2 Cu3O(8+x) deposits has been determined from transmission electron microscopy, electron backscatter diffraction patterns and x-ray diffraction. The small-grained deposits had excellent c-axis alignment and contained colonies of grains with similar but not identical a-axis orientations. Most grain boundaries within a colony have small misorientation angles and should not be weak links. It is proposed that long range conduction utilizes a percolative network of small angle grain boundaries at colony intersections.

Effects of nozzle type and spray angle on spray deposition in ivy pot plants.

PubMed

Foqué, Dieter; Nuyttens, David

2011-02-01

Fewer plant protection products are now authorised for use in ornamental growings. Frequent spraying with the same product or a suboptimal technique can lead to resistance in pests and diseases. Better application techniques could improve the sustainable use of the plant protection products still available. Spray boom systems--instead of the still predominantly used spray guns--might improve crop protection management in greenhouses considerably. The effect of nozzle type, spray pressure and spray angle on spray deposition and coverage in ivy pot plants was studied, with a focus on crop penetration and spraying the bottom side of the leaves in this dense crop. The experiments showed a significant and important effect of collector position on deposition and coverage in the plant. Although spray deposition and coverage on the bottom side of the leaves are generally low, they could be improved 3.0-4.9-fold using the appropriate application technique. When using a spray boom in a dense crop, the nozzle choice, spray pressure and spray angle should be well considered. The hollow-cone, the air-inclusion flat-fan and the standard flat-fan nozzle with an inclined spray angle performed best because of the effect of swirling droplets, droplets with a high momentum and droplet direction respectively. Copyright © 2010 Society of Chemical Industry.

Method of fabricating conducting oxide-silicon solar cells utilizing electron beam sublimation and deposition of the oxide

DOEpatents

Feng, Tom; Ghosh, Amal K.

1979-01-01

In preparing tin oxide and indium tin oxide-silicon heterojunction solar cells by electron beam sublimation of the oxide and subsequent deposition thereof on the silicon, the engineering efficiency of the resultant cell is enhanced by depositing the oxide at a predetermined favorable angle of incidence. Typically the angle of incidence is between 40.degree. and 70.degree. and preferably between 55.degree. and 65.degree. when the oxide is tin oxide and between 40.degree. and 70.degree. when the oxide deposited is indium tin oxide. gi The Government of the United States of America has rights in this invention pursuant to Department of Energy Contract No. EY-76-C-03-1283.

Wide angle sun sensor. [consisting of cylinder, insulation and pair of detectors

NASA Technical Reports Server (NTRS)

Schumacher, L. L. (Inventor)

1975-01-01

A single-axis sun sensor consists of a cylinder of an insulating material on which at least one pair of detectors is deposited on a circumference of the cylinder, was disclosed. At any time only one-half of the cylinder is illuminated so that the total resistance of the two detectors is a constant. Due to the round surface on which the detectors are deposited, the sensor exhibits a linear wide angle of + or - 50 deg to within an accuracy of about 2%. By depositing several pairs of detectors on adjacent circumferences, sufficient redundancy is realized to provide high reliability. A two-axis sensor is provided by depositing detectors on the surface of a sphere along at least two orthogonal great circles.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rajkumar, K.; Rajavel, K.; Cameron, D. C.

This paper reports the electrowetting properties of liquid droplet on superhydrophobic silicon nanowires with Atomic layer deposited (ALD) Al{sub 2}O{sub 3} as dielectric layer. Silicon wafer were etched by metal assisted wet chemical etching with silver as catalyst. ALD Al{sub 2}O{sub 3} films of 10nm thickness were conformally deposited over silicon nanowires. Al{sub 2}O{sub 3} dielectric film coated silicon nanowires was chemically modified with Trichloro (1H, 1H, 2H, 2H-perfluorooctyl) silane to make it superhydrophobic(SHP). The contact angle was measured and all the samples exhibited superhydrophobic nature with maximum contact angles of 163° and a minimum contact angle hysteresis of 6°.more » Electrowetting induced a maximum reversible decrease of the contact angle of 20°at 150V in air.« less

The Effects of Grain Boundaries on the Current Transport Properties in YBCO-Coated Conductors

NASA Astrophysics Data System (ADS)

Yang, Chao; Xia, Yudong; Xue, Yan; Zhang, Fei; Tao, Bowan; Xiong, Jie

2015-10-01

We report a detailed study of the grain orientations and grain boundary (GB) networks in Y2O3 films grown on Ni-5 at.%W substrates. Electron back scatter diffraction (EBSD) exhibited different GB misorientation angle distributions, strongly decided by Y2O3 films with different textures. The subsequent yttria-stabilized zirconia (YSZ) barrier and CeO2 cap layer were deposited on Y2O3 layers by radio frequency sputtering, and YBa2Cu3O7-δ (YBCO) films were deposited by pulsed laser deposition. For explicating the effects of the grain boundaries on the current carry capacity of YBCO films, a percolation model was proposed to calculate the critical current density ( J c) which depended on different GB misorientation angle distributions. The significantly higher J c for the sample with sharper texture is believed to be attributed to improved GB misorientation angle distributions.

Effect of spray angle and spray volume on deposition of a medium droplet spray with air support in ivy pot plants.

PubMed

Foqué, Dieter; Pieters, Jan G; Nuyttens, David

2014-03-01

Spray boom systems, an alternative to the predominantly-used spray guns, have the potential to considerably improve crop protection management in glasshouses. Based on earlier experiments, the further optimization of the deposits of a medium spray quality extended range flat fan nozzle type using easy adjustable spray boom settings was examined. Using mineral chelate tracers and water sensitive papers, the spray results were monitored at three plant levels, on the upper side and the underside of the leaves, and on some off-target collectors. In addition, the deposition datasets of all tree experiments were compared. The data showed that the most efficient spray distribution with the medium spray quality flat fan nozzles was found with a 30° forward angled spray combined with air support and an application rate of 1000 L ha(-1) . This technique resulted in a more uniform deposition in the dense canopy and increased spray deposition on the lower side of the leaves compared with the a standard spray boom application. Applying 1000 L ha(-1) in two subsequent runs instead of one did not seem to show any added value. Spray deposition can be improved hugely simply by changing some spray boom settings like nozzle type, angling the spray, using air support and adjusting the spray volume to the crop. © 2013 Society of Chemical Industry.

Supercritical strata in Lower Paleozoic fluvial rocks: a super critical link to upper flow regime processes and preservation in nature

NASA Astrophysics Data System (ADS)

Lowe, David; Arnott, Bill

2015-04-01

Recent experimental work has much improved our understanding of the lithological attributes of open-channel supercritical flow deposits, namely those formed by antidunes, chutes-and-pools and cyclic steps. However their limited documentation in the ancient sedimentary record brings into question details about their geological preservation. Antidune, chute-and-pool and cyclic step deposits are well developed in sandy ephemeral fluvial deposits of the Upper Cambrian - Lower Ordovician Potsdam Group in the Ottawa Embayment of eastern North America. These high energy fluvial strata form dm- to a few m-thick units intercalated within thick, areally expansive successions of sheet sandstones consisting mostly of wind ripple and adhesion stratification with common deflation lags. Collectively these strata record deposition in a semi-arid environment in which rare, episodic high-energy fluvial events accounted for most of the influx of sediment from upland sources. Following deposition, however, extensive aeolian processes reworked the sediment pile, and hence modified profoundly the preserved stratigraphic record. Antidune deposits occur as 0.2 - 1.6 m thick cosets made up of 2 - 15 cm thick lenticular sets of low angle (≤ 20o) cross-stratified, medium- to coarse-grained sandstone bounded by low-angle (5 - 15o) concave-upward scours and, in many cases, capped by low angle (10 - 15o) convex-upwards symmetrical formsets. Chute-and-pool deposits form single sets, 5 - 55 cm thick and 0.6 - 6 m wide, with scoured bases and low to high angle (5 - 25o) sigmoidal cross-strata consisting of medium- to coarse-grained sandstone. Cyclic step deposits consist of trough cross-stratified sets, 20 cm - 1.6 m thick, 2.5 - 12 m long and 7 - 35 m wide, typically forming trains that laterally are erosively juxtaposed at regularly-spaced intervals. They are composed of medium- to coarse-grained sandstone with concave-up, moderate to high angle (15 - 35o) cross-strata with tangential bases that conform to the shape of the basal bounding surface of the set. Antidune and cyclic step deposits are common and fill 0.4 - 1.8 m deep channels, which then are generally overlain by extensive (>1 km) aeolian deflation surfaces. Chute-and-pool strata, however, are rare and only occur as isolated scour-filling sets within unconfined floodplain deposits. Nowhere in outcrop do different kinds of supercritical bedform deposits interfinger or appear related to the same flow event, suggesting that individual packages of supercritical strata were deposited by discreet, rapidly waning flows with little time for incremental growth or deposition under changing flow conditions. The stratal characteristics and geometries of channel-filling antidune and cyclic step cosets in the Potsdam are similar to those produced in steady experimental flows with high rates of aggradation. Similar conditions in the Potsdam were probably attained because the flows were channelized, which also caused the freshly deposited sediment to lie beneath the water table, and hence beneath the effects of extensive post-flood aeolian deflation. Conversely, scour-filling chute-and-pool deposits formed on the floodplain where highly unsteady, erosive and rapidly waning unconfined flows formed isolated, partly-filled, erosively-based, ephemeral structures. Moreover, being formed on the surface of the floodplain subjected these deposits to extensive post-depositional reworking, and as a consequence caused them to be poorly preserved.

Photometric follow-up of sungrazing comet C/2012 S1 ISON from OAdM and other observatories

NASA Astrophysics Data System (ADS)

Trigo-Rodríguez, J. M.; Moyano-Cambero, C. E.; Meech, K. J.; Rodríguez, D.; Sánchez, A.; Lacruz, J.

2013-09-01

Comet C/2012 S1 ISON was discovered on Sept. 21st, 2012 by Russian amateur astronomers Vitaly Nevski and Artyom Novichonok in the framework of a monitoring program called the International Scientific Optical Network (giving the acronym ISON from which the comet has been named). At discovery the comet was at a heliocentric distance of 6.29 A.U. and its magnitude was +18.8, but the computed orbit indicated that the comet was following a nearly parabolic orbit. The current orbit brings C/2012 S1 ISON to an extremely small perihelion distance of about 1 milion km on Nov. 28th, 2013. We have set up a multiband photometric monitoring of this sungrazing comet using 0.8m Telescope Joan Oró of the Montsec Astronomical Observatory (OAdM: www.oadm.cat) and several medium-size amateur telescopes with dedicated experience in cometary photometry [1, 2]. Comet sungrazers are interesting objects as they probably originate from the dynamical evolution of long period comets that typically end their lives colliding with the Sun [3]. They are though to be fragments of primitive ice-rich bodies gravitationally dispersed during the early stages of solar system evolution [4].

One-step microwave plasma enhanced chemical vapor deposition (MW-PECVD) for transparent superhydrophobic surface

NASA Astrophysics Data System (ADS)

Thongrom, Sukrit; Tirawanichakul, Yutthana; Munsit, Nantakan; Deangngam, Chalongrat

2018-02-01

We demonstrate a rapid and environmental friendly fabrication technique to produce optically clear superhydrophobic surfaces using poly (dimethylsiloxane) (PDMS) as a sole coating material. The inert PDMS chain is transformed into a 3-D irregular solid network through microwave plasma enhanced chemical vapor deposition (MW-PECVD) process. Thanks to high electron density in the microwave-activated plasma, coating can be done in just a single step with rapid deposition rate, typically much shorter than 10 s. Deposited layers show excellent superhydrophobic properties with water contact angles of ∼170° and roll-off angles as small as ∼3°. The plasma-deposited films can be ultrathin with thicknesses under 400 nm, greatly diminishing the optical loss. Moreover, with appropriate coating conditions, the coating layer can even enhance the transmission over the entire visible spectrum due to a partial anti-reflection effect.

The influence of slope-angle ratio on the dynamics of granular flows: insights from laboratory experiments

NASA Astrophysics Data System (ADS)

Sulpizio, R.; Castioni, D.; Rodriguez-Sedano, L. A.; Sarocchi, D.; Lucchi, F.

2016-11-01

Laboratory experiments on granular flows using natural material were carried out in order to investigate the behaviour of granular flows passing over a break in slope. Sensors in the depositional area recorded the flow kinematics, while video footage permitted reconstruction of the deposit formation, which allowed investigation of the deposit shape as a function of the change in slope. We defined the slope-angle ratio as the proportion between slope angle in the depositional area and that of the channel. When the granular flow encounters the break in slope part of the flow front forms a bouncing clast zone due to elastic impact with the expansion box floor. During this process, part of the kinetic energy of the dense granular flow is transferred to elutriating fine ash, which subsequently forms turbulent ash cloud accompanying the granular flow until it comes to rest. Morphometric analysis of the deposits shows that they are all elliptical, with an almost constant minor axis and a variable major axis. The almost constant value of the minor axis relates to the spreading angle of flow at the end of the channel, which resembles the basal friction angle of the material. The variation of the major axis is interpreted to relate to the effect of competing inertial and frictional forces. This effect also reflects the partitioning of centripetal and tangential velocities, which changes as the flow passes over the break in slope. After normalization, morphometric data provided empirical relationships that highlight the dependence of runout from the product of slope-angle ratio and the difference in height between granular material release and deposit. The empirical relationships were tested against the runouts of hot avalanches formed during the 1944 ad eruption at Vesuvius, with differences among actual and calculated values are between 1.7 and 15 %. Velocity measurements of laboratory granular flows record deceleration paths at different breaks in slope. When normalized, the velocity data show third-order polynomial fit, highlighting a complex behaviour involving interplay between inertial and frictional forces. The theoretical velocity decays were tested against the data published for volcaniclastic debris flows of the 5-6 May 1998 event in the Sarno area. The comparison is very good for non-channelized debris flows, with significant differences between actual and calculated velocities for the channelized debris flows.

Changes of polarimetric scattering characteristics of ALOS PALSAR caused by the 2011 Eruption of Shinmoe-dake Volcano

NASA Astrophysics Data System (ADS)

Ohkura, Hiroshi

Full polarimetric SAR images of ALOS PALSAR of Shinmoe-dake volcano in Japan were analyzed. The volcano erupted in January, 2011 and volcano ash deposited more than 10 cm in 12 km (2) and 1 m in 2 km (2) . Two images before and after the eruption were compared based on a point view of the four-component scattering model to detect changes of polarimetric scattering characteristics. The main detected changes are as follows. Total power of the four-component scattering model decreased on a farslope after the eruption. An incident angle on a farslope is larger than the angle on a foreslope. Decrease of surface roughness due to deposited volcanic ashes makes back-scattering smaller in the area of a larger incidence angle. However the rate of the double-bounce component got higher in a forest at the foot of a mountain slope and on a plain, where the ground surface is almost horizontal and the incident angle is relatively-large. Decrease of roughness of the forest floor increases forward scattering on the floor of the larger incident angle. This increases the double-bounced scattering due to bouncing back between the forest floor and trunks which stand "perpendicularly" on the almost horizontal forest floor. The rate of the surface scattering component got higher around an area where layover occurred. In the study area, most of layovers occurred at a ridge where an incidence angle was small. Decrease of surface roughness due to the ash deposit increases the surface scattering power in the area of the small incidence angle.

Effect of nanoparticle size on sessile droplet contact angle

NASA Astrophysics Data System (ADS)

Munshi, A. M.; Singh, V. N.; Kumar, Mukesh; Singh, J. P.

2008-04-01

We report a significant variation in the static contact angle measured on indium oxide (IO) nanoparticle coated Si substrates that have different nanoparticle sizes. These IO nanoparticles, which have well defined shape and sizes, were synthesized by chemical vapor deposition in a horizontal alumina tube furnace. The size of the IO nanoparticles was varied by changing the source material, substrate temperature, and the deposition time. A sessile droplet method was used to determine the macroscopic contact angle on these IO nanoparticle covered Si substrate using two different liquids: de-ionized water and diethylene glycol (DEG). It was observed that contact angle depends strongly on the nanoparticle size. The contact angle was found to vary from 24° to 67° for de-ionized water droplet and from 15° to 60° for DEG droplet, for the nanoparticle sizes varying from 14 to 620 nm. The contact angle decreases with a decrease in the particles size. We have performed a theoretical analysis to determine the dependence of contact angle on the nanoparticle size. This formulation qualitatively shows a similar trend of decrease in the contact angle with a decrease in nanoparticle size. Providing a rough estimate of nanoparticle size by sessile droplet contact angle measurement is the novelty in this work.

Predictors of Change in Adherence Status from 1 Year to the Next Among Patients with Type 2 Diabetes Mellitus on Oral Antidiabetes Drugs.

PubMed

Saundankar, Vishal; Peng, Xiaomei; Fu, Haoda; Ascher-Svanum, Haya; Rodriguez, Angel; Ali, Ayad; Slabaugh, Lane; Young, Peinie; Louder, Anthony

2016-05-01

Diabetes is a leading cause of morbidity, mortality, and medical resource utilization in the United States and worldwide. Treatment is aimed at keeping blood glucose levels close to normal and preventing or delaying medical complications. It has been estimated that only 50% of patients with diabetes in the United States achieve glycosylated hemoglobin A1c level < 7%. Nonadherence to antidiabetic medications has been identified as a major factor related to poor glycemic control. To (a) assess adult patients with type 2 diabetes mellitus (T2DM) whose adherence status to oral antidiabetic drugs (OADs) changed from 1 year to the next and (b) identify predictors of change in adherence status. This retrospective study of the Humana Medicare Advantage Database included patients with T2DM and continuous enrollment between 2010 and 2012. Proportion of days covered (PDC) by OADs was calculated for each of the 3 study years (2010, 2011, 2012). Patients were classified as adherent (PDC ≥ 80%) or nonadherent (PDC < 80%) during each year. Patient characteristics from the baseline period (2010) were used as covariates, and adherence status changes from baseline to follow-up year (2011) were used as response variables. Data from the subsequent study periods (2011 as baseline, 2012 as follow-up) were used to validate the model (final model). A total of 238,402 patients met inclusion criteria. Among them, 144,216 (60.5%) were adherent, and 94,186 (39.5%) were nonadherent during the baseline period. Change in adherence status from baseline to follow-up year was observed in 31,320 (21.7%) patients that were adherent and 39,284 (41.7%) patients that were nonadherent during the baseline year. The final model for baseline adherent patients had a receiver-operating characteristic (ROC) index of 73% and a misclassification rate of 39%. The predictors of highest importance were identified as total number of prescriptions filled with 90-day supply, diabetes-related pill burden, longest gap in OADs, total number of antidiabetic classes filled, and copay for the last OAD filled. The final model had a sensitivity value of 76.4%. The final model for baseline nonadherent patients had a ROC index of 68%, a misclassification rate of 36.4%, and sensitivity value of 52.9%. The predictors of highest importance were diabetes-related pill burden, longest gap in OADs, month-wise patient oscillation from adherent to nonadherent during baseline year, total number of prescriptions filled with a 90-day supply, and total pill burden during the baseline year. One third of the T2DM patients changed adherence status from 1 year to the next, and factors associated with adherence status changes were identified. Predictive models such as those used in this study can serve as useful and cost-effective tools for payers, helping to identify members that should be targeted for adherence enhancement programs and, ultimately, to improve patients' long-term outcomes. Funding for this research was provided by Eli Lilly and Company. Comprehensive Health Insights, owned by Humana, completed this study. Peng, Fu, Ascher-Svanum, Ali, and Rodriguez are employees of Eli Lilly and Company. Saundankar and Louder are employed by Comprehensive Health Insights, and Slabaugh and Young are employed by Humana. Study concept and design were contributed by Peng, Ascher-Svanum, and Young. Saundankar and Louder took the lead in data collection, while Saundankar, Peng, Fu, and Louder interpreted the data. The manuscript was written by Saundankar, Peng, Fu, and Louder and revised by Saundankar, Rodriguez, Ali, and Louder.

Physical vapor deposition and metalorganic chemical vapor deposition of yttria-stabilized zirconia thin films

NASA Astrophysics Data System (ADS)

Kaufman, David Y.

Two vapor deposition techniques, dual magnetron oblique sputtering (DMOS) and metalorganic chemical vapor deposition (MOCVD), have been developed to produce yttria-stabilized zirconia (YSZ) films with unique microstructures. In particular, biaxially textured thin films on amorphous substrates and dense thin films on porous substrates have been fabricated by DMOS and MOCVD, respectively. DMOS YSZ thin films were deposited by reactive sputtering onto Si (native oxide surface) substrates positioned equidistant between two magnetron sources such that the fluxes arrived at oblique angles with respect to the substrate normal. Incident fluxes from two complimentary oblique directions were necessary for the development of biaxial texture. The films displayed a strong [001] out-of-plane orientation with the <110> direction in the film aligned with the incident flux. Biaxial texture improved with increasing oblique angle and film thickness, and was stronger for films deposited with Ne than with Ar. The films displayed a columnar microstructure with grain bundling perpendicular to the projected flux direction, the degree of which increased with oblique angle and thickness. The texture decreased by sputtering at pressures at which the flux of sputtered atoms was thermalized. These results suggested that grain alignment is due to directed impingement of both sputtered atoms and reflected energetic neutrals. The best texture, a {111} phi FWHM of 23°, was obtained in a 4.8 mum thick film deposited at an oblique angle of 56°. MOCVD YSZ thin films were deposited in a vertical cold-wall reactor using Zr(tmhd)4 and Y(tmhd)3 precursors. Fully stabilized YSZ films with 9 mol% could be deposited by controlling the bubbler temperatures. YSZ films on Si substrates displayed a transition at 525°C from surface kinetic limited growth, with an activation energy of 5.5 kJ/mole, to mass transport limited growth. Modifying the reactor by lowering the inlet height and introducing an Ar baffle ring increased the growth rates to 2.5 mum/hr. Dense, gas impermeable 4-6 mum YSZ thin films were deposited on porous (La,Sr)Mno3 cathode substrates. Solid oxide fuel cells, fabricated by sputtering on a Ni-YSZ anode, achieved open circuit voltages ≥94% theoretical, and maximum power densities at 750°C comparable with commercial conventional SOFC's operated at higher temperatures.

Modification of the morphology and optical properties of SnS films using glancing angle deposition technique

NASA Astrophysics Data System (ADS)

Sazideh, M. R.; Dizaji, H. Rezagholipour; Ehsani, M. H.; Moghadam, R. Zarei

2017-05-01

Tin sulfide (SnS) films were prepared by thermal evaporation method using Glancing Angle Deposition (GLAD) technique at zero and different oblique incident flux angles (α = 45°, 55°, 65°, 75° and 85°). The physical properties of prepared films were systematically investigated. The X-ray diffraction analysis indicated that the film deposited at α = 0° formed as single phase with an orthorhombic structure. However, the layers became amorphous at α = 45°, 55°, 65°, 75° and 85°. Beside the appearance of amorphous feature in the film prepared at α higher than zero, Sn2S3 phase was also observed. The top and cross-sectional field emission scanning electron microscope (FESEM) images of the samples showed noticeable changes in the structure and morphology of individual nano-plates as a function of incident angle. The band gap and refractive index values of the films were calculated by optical transmission measurements. The optical band-gap values were observed to increase with increasing the incident flux angle. This can be due to presence of Sn2S3 phase observed in the samples produced at α values other than zero. The effective refractive index and porosity exhibit an opposite evolution as the incident angle α rises. At α = 85° the layers show a considerable change in effective refractive index (Δn = 1.7) at near-IR spectral range.

Giant landslide deposits in northwest Argentina

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fauque, L.; Strecker, M.R.; Bloom, A.L.

1985-01-01

Giant Quaternary landslide deposits occur along mountain fronts in the structural transition zone between the high-angle reverse-fault-bounded Sierras Pampeanas and the low-angle thrust belt of the Sierras Subandinas. There are two modes of occurrence: (1) chaotic masses without distinct geometry, and (2) masses with distinct lobate geometry similar to glacial moraines. Type (1) deposits occur where the moving rock mass followed a narrow valley and blocked the drainage. Many of these caused subsequent formation of lakes and changed the sedimentation processes on pediments at the mountain fronts. In type (2) deposits, lateral and frontal ridges are up to 10 mmore » higher than the interior parts; in some places pressure ridges within the lobes are well preserved. Type (2) deposits show reverse grading and were deposited on relatively smooth pediments or alluvial fans. The lobate geometry strongly suggests that type (2) deposits are a product of flowage and are debris stream or sturzstrom deposits (sense of Heim, 1932 and Hsu, 1975). All investigated deposits occur in areas of demonstrated Quaternary faulting and are interpreted as the result of tectonic movements, although structural inhomogeneities in the source area may have been a significant factor for some of the landslides. No datable materials have yet been found associated with the deposits.« less

Effect of Impact Angle on Ceramic Deposition Behavior in Composite Cold Spray: A Finite-Element Study

NASA Astrophysics Data System (ADS)

Chakrabarty, Rohan; Song, Jun

2017-10-01

During the cold spraying of particle-reinforced metal matrix composite coatings (ceramic and metal particles mixture) on metal substrates, ceramic particles may either get embedded in the substrate/deposited coating or may rebound from the substrate surface. In this study, the dependence of the ceramic rebounding phenomenon on the spray angle and its effect on substrate erosion have been analyzed using finite-element analysis. From the numerical simulations, it was found that the ceramic particle density and substrate material strength played the major roles in determining the embedding and ceramic retention behavior. Substrate material erosion also influenced the ceramic retention, and the material loss increased as the impact angles decreased from normal. In general, the results concluded that decreasing the impact angle promoted the retention possibility of ceramics in the substrate. This study provides new theoretical insights into the effect of spray angles on the ceramic retention and suggests a new route toward optimizing the spraying process to increase the ceramic retention in composite coatings cold spray.

A new highly automated sputter equipment for in situ investigation of deposition processes with synchrotron radiation.

PubMed

Döhrmann, Ralph; Botta, Stephan; Buffet, Adeline; Santoro, Gonzalo; Schlage, Kai; Schwartzkopf, Matthias; Bommel, Sebastian; Risch, Johannes F H; Mannweiler, Roman; Brunner, Simon; Metwalli, Ezzeldin; Müller-Buschbaum, Peter; Roth, Stephan V

2013-04-01

HASE (Highly Automated Sputter Equipment) is a new mobile setup developed to investigate deposition processes with synchrotron radiation. HASE is based on an ultra-high vacuum sputter deposition chamber equipped with an in-vacuum sample pick-and-place robot. This enables a fast and reliable sample change without breaking the vacuum conditions and helps to save valuable measurement time, which is required for experiments at synchrotron sources like PETRA III at DESY. An advantageous arrangement of several sputter guns, mounted on a rotative flange, gives the possibility to sputter under different deposition angles or to sputter different materials on the same substrate. The chamber is also equipped with a modular sample stage, which allows for the integration of different sample environments, such as a sample heating and cooling device. The design of HASE is unique in the flexibility. The combination of several different sputtering methods like standard deposition, glancing angle deposition, and high pressure sputter deposition combined with heating and cooling possibilities of the sample, the large exit windows, and the degree of automation facilitate many different grazing incidence X-ray scattering experiments, such as grazing incidence small and wide angle X-ray scattering, in one setup. In this paper we describe in detail the design and the performance of the new equipment and present the installation of the HASE apparatus at the Micro and Nano focus X-ray Scattering beamline (MiNaXS) at PETRA III. Furthermore, we describe the measurement options and present some selected results. The HASE setup has been successfully commissioned and is now available for users.

A new highly automated sputter equipment for in situ investigation of deposition processes with synchrotron radiation

NASA Astrophysics Data System (ADS)

Döhrmann, Ralph; Botta, Stephan; Buffet, Adeline; Santoro, Gonzalo; Schlage, Kai; Schwartzkopf, Matthias; Bommel, Sebastian; Risch, Johannes F. H.; Mannweiler, Roman; Brunner, Simon; Metwalli, Ezzeldin; Müller-Buschbaum, Peter; Roth, Stephan V.

2013-04-01

HASE (Highly Automated Sputter Equipment) is a new mobile setup developed to investigate deposition processes with synchrotron radiation. HASE is based on an ultra-high vacuum sputter deposition chamber equipped with an in-vacuum sample pick-and-place robot. This enables a fast and reliable sample change without breaking the vacuum conditions and helps to save valuable measurement time, which is required for experiments at synchrotron sources like PETRA III at DESY. An advantageous arrangement of several sputter guns, mounted on a rotative flange, gives the possibility to sputter under different deposition angles or to sputter different materials on the same substrate. The chamber is also equipped with a modular sample stage, which allows for the integration of different sample environments, such as a sample heating and cooling device. The design of HASE is unique in the flexibility. The combination of several different sputtering methods like standard deposition, glancing angle deposition, and high pressure sputter deposition combined with heating and cooling possibil-ities of the sample, the large exit windows, and the degree of automation facilitate many different grazing incidence X-ray scattering experiments, such as grazing incidence small and wide angle X-ray scattering, in one setup. In this paper we describe in detail the design and the performance of the new equipment and present the installation of the HASE apparatus at the Micro and Nano focus X-ray Scattering beamline (MiNaXS) at PETRA III. Furthermore, we describe the measurement options and present some selected results. The HASE setup has been successfully commissioned and is now available for users.

Molecular Dynamics Simulations of Surface Processes: Oxygen Recombination on Silica Surfaces at High Temperature

DTIC Science & Technology

2007-07-01

SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT UU 18 . NUMBER OF PAGES 22 19a. NAME OF RESPONSIBLE PERSON a. REPORT unclassified b. ABSTRACT...unclassified c. THIS PAGE unclassified Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39- 18 Molecular Dynamics Simulations of Surface...phase. O + Oad + silica -------> O2(v,j) + silica ( 18 ) The first step is

In situ grazing incidence small-angle X-ray scattering investigation of polystyrene nanoparticle spray deposition onto silicon.

PubMed

Herzog, Gerd; Benecke, Gunthard; Buffet, Adeline; Heidmann, Berit; Perlich, Jan; Risch, Johannes F H; Santoro, Gonzalo; Schwartzkopf, Matthias; Yu, Shun; Wurth, Wilfried; Roth, Stephan V

2013-09-10

We investigated the spray deposition and subsequent self-assembly during drying of a polystyrene nanoparticle dispersion with in situ grazing incidence small-angle X-ray scattering at high time resolution. During the fast deposition of the dispersion and the subsequent evaporation of the solvent, different transient stages of nanoparticle assembly can be identified. In the first stage, the solvent starts to evaporate without ordering of the nanoparticles. During the second stage, large-scale structures imposed by the breakup of the liquid film are observable. In this stage, the solvent evaporates further and nanoparticle ordering starts. In the late third drying stage, the nanoparticles self-assemble into the final layer structure.

Drug usage patterns and treatment costs in newly-diagnosed type 2 diabetes mellitus cases, 2007 vs 2012: findings from a large US healthcare claims database analysis.

PubMed

Weng, W; Liang, Y; Kimball, E S; Hobbs, T; Kong, S; Sakurada, B; Bouchard, J

2016-07-01

Objective To explore trends in demographics, comorbidities, anti-diabetic drug usage, and healthcare utilization costs in patients with newly-diagnosed type 2 diabetes mellitus (T2DM) using a large US claims database. Methods For the years 2007 and 2012, Truven Health Marketscan Research Databases were used to identify adults with newly-diagnosed T2DM and continuous 12-month enrollment with prescription benefits. Variables examined included patient demographics, comorbidities, inpatient utilization patterns, healthcare costs (inpatient and outpatient), drug costs, and diabetes drug claim patterns. Results Despite an increase in the overall database population between 2007-2012, the incidence of newly-diagnosed T2DM decreased from 1.1% (2007) to 0.65% (2012). Hyperlipidemia and hypertension were the most common comorbidities and increased in prevalence from 2007 to 2012. In 2007, 48.3% of newly-diagnosed T2DM patients had no claims for diabetes medications, compared with 36.2% of patients in 2012. The use of a single oral anti-diabetic drug (OAD) was the most common diabetes medication-related claim (46.2% of patients in 2007; 56.7% of patients in 2012). Among OAD monotherapy users, metformin was the most commonly used and increased from 2007 (74.7% of OAD monotherapy users) to 2012 (90.8%). Decreases were observed for sulfonylureas (14.1% to 6.2%) and thiazolidinediones (7.3% to 0.6%). Insulin, predominantly basal insulin, was used by 3.9% of patients in 2007 and 5.3% of patients in 2012. Mean total annual healthcare costs increased from $13,744 in 2007 to $15,175 in 2012, driven largely by outpatient services, although costs in all individual categories of healthcare services (inpatient and outpatient) increased. Conversely, total drug costs per patient were lower in 2012 compared with 2007. Conclusions Despite a drop in the rate of newly-diagnosed T2DM from 2007 to 2012 in the US, increased total medical costs and comorbidities per individual patient suggest that the clinical and economic trends for T2DM are not declining.

Patient-level meta-analysis of efficacy and hypoglycaemia in people with type 2 diabetes initiating insulin glargine 100U/mL or neutral protamine Hagedorn insulin analysed according to concomitant oral antidiabetes therapy.

PubMed

Owens, David R; Traylor, Louise; Mullins, Peter; Landgraf, Wolfgang

2017-02-01

Evaluate efficacy and hypoglycaemia according to concomitant oral antidiabetes drug (OAD) in people with type 2 diabetes initiating insulin glargine 100U/mL (Gla-100) or neutral protamine Hagedorn (NPH) insulin once daily. Four studies (target fasting plasma glucose [FPG] ⩽100mg/dL [⩽5.6mmol/L]; duration ⩾24weeks) were included. Standardised data from 2091 subjects (Gla-100, n=1024; NPH insulin, n=1067) were analysed. Endpoints included glycated haemoglobin (HbA1c) and FPG change, glycaemic target achievement, hypoglycaemia, weight change, and insulin dose. Mean HbA1c and FPG reductions were similar with Gla-100 and NPH insulin regardless of concomitant OAD (P=0.184 and P=0.553, respectively) and similar proportions of subjects achieved HbA1c <7.0% (P=0.603). There was a trend for more subjects treated with Gla-100 achieving FPG ⩽100mg/dL versus NPH insulin (relative risk [RR] 1.09 [95% confidence interval (CI) 0.97-1.23]; P=0.135). Plasma glucose confirmed (<70mg/dL) overall and nocturnal hypoglycaemia incidences and rates were lower with Gla-100 versus NPH insulin (overall RR 0.93 [95% CI 0.87-1.00]; P=0.041; nocturnal RR 0.73 [95% CI 0.65-0.83]; P<0.001). After 24weeks, weight gain and insulin doses were higher with Gla-100 versus NPH insulin (2.7kg vs 2.3kg, P=0.009 and 0.42U/kg vs 0.39U/kg; P=0.003, respectively). Insulin doses were higher when either insulin was added to sulfonylurea alone. Pooled results from treat-to-target trials in insulin-naïve people with type 2 diabetes demonstrate a significantly lower overall and nocturnal hypoglycaemia risk across different plasma glucose definitions with Gla-100 versus NPH insulin at similar glycaemic control. OAD therapy co-administered with Gla-100 or NPH insulin impacts glycaemic control and overall nocturnal hypoglycaemia risk. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Real-life efficacy and safety of vildagliptin compared with sulfonylureas as add-on to metformin in patients with type 2 diabetes mellitus in Germany.

PubMed

Göke, R; Gruenberger, J B; Bader, G; Dworak, M

2014-05-01

Metformin is an established first-line treatment for type 2 diabetes mellitus (T2DM) patients, but intensification of oral anti-diabetes therapy is usually required over time. A large observational study of 45,868 T2DM patients in 27 countries (EDGE) was conducted to compare the effectiveness and safety of vildagliptin as add-on therapy to another oral anti-diabetes drug (OAD) vs other dual OAD combinations. This report presents results from a post-hoc analysis of patients in Germany who received vildagliptin or a sulfonylurea (SU) in combination with metformin. Patients inadequately controlled with monotherapy became eligible only after the add-on treatment was finalized. Patients included were assigned to receive either vildagliptin or another OAD (SUs, thiazolidinediones, glinides, α-glucosidase inhibitors, or metformin; DPP-4 inhibitors or glucagon-like peptide-1 [GLP-1] mimetics/analogs were excluded). The primary end-point was the proportion of patients achieving a reduction in HbA1c >0.3% without peripheral edema, hypoglycemia, discontinuation due to gastrointestinal event, or weight gain ≥5%. Of 8887 patients enrolled in Germany, 6439 received vildagliptin and 971 received SUs as add-on to metformin. The primary end-point was reached in 34.9% and 29.6% of patients in the vildagliptin and SU groups, respectively, with an unadjusted odds ratio of 1.27 (95% CI = 1.09, 1.47; p = 0.001). HbA1c decreased in both cohorts from baseline (-0.7% with vildagliptin vs -0.5% with SUs), with a mean between-group difference of -0.2% (95% CI = -0.22, -0.09). The number of hypoglycemic events was 4-fold higher in the SU group than in the vildagliptin group (vildagliptin = 0.11%; SU = 0.41%). In a real-life setting, vildagliptin was associated with a numerically greater reduction in HbA1c, less hypoglycemia, and more patients reaching target HbA1c without hypoglycemia or weight gain compared with SUs. Open-label design and under reporting of adverse events are limitations of this post hoc analysis.

Glycaemic control and hypoglycaemia with new insulin glargine 300 U/ml versus insulin glargine 100 U/ml in people with type 2 diabetes using basal insulin and oral antihyperglycaemic drugs: the EDITION 2 randomized 12-month trial including 6-month extension.

PubMed

Yki-Järvinen, H; Bergenstal, R M; Bolli, G B; Ziemen, M; Wardecki, M; Muehlen-Bartmer, I; Maroccia, M; Riddle, M C

2015-12-01

To compare the efficacy and safety of new insulin glargine 300 U/ml (Gla-300) with insulin glargine 100 U/ml (Gla-100) over 12 months of treatment in people with type 2 diabetes using basal insulin and oral antihyperglycaemic drugs (OADs). EDITION 2 (NCT01499095) was a randomized, 6-month, multicentre, open-label, two-arm, phase IIIa study investigating once-daily Gla-300 versus Gla-100, plus OADs (excluding sulphonylureas), with a 6-month safety extension. Similar numbers of participants in each group completed 12 months of treatment [Gla-300, 315 participants (78%); Gla-100, 314 participants (77%)]. The reduction in glycated haemoglobin was maintained for 12 months with both treatments: least squares (LS) mean (standard error) change from baseline -0.55 (0.06)% for Gla-300 and -0.50 (0.06)% for Gla-100; LS mean difference -0.06 [95% confidence interval (CI) -0.22 to 0.10)%]. A significant relative reduction of 37% in the annualized rate of nocturnal confirmed [≤3.9 mmol/l (≤70 mg/dl)] or severe hypoglycaemia was observed with Gla-300 compared with Gla-100: rate ratio 0.63 [(95% CI 0.42-0.96); p = 0.031], and fewer participants experienced ≥1 event [relative risk 0.84 (95% CI 0.71-0.99)]. Severe hypoglycaemia was infrequent. Weight gain was significantly lower with Gla-300 than Gla-100 [LS mean difference -0.7 (95% CI -1.3 to -0.2) kg; p = 0.009]. Both treatments were well tolerated with a similar pattern of adverse events (incidence of 69 and 60% in the Gla-300 and Gla-100 groups). In people with type 2 diabetes treated with Gla-300 or Gla-100, and non-sulphonylurea OADs, glycaemic control was sustained over 12 months, with less nocturnal hypoglycaemia in the Gla-300 group. © 2015 The Authors. Diabetes, Obesity and Metabolism published by John Wiley & Sons Ltd.

Correlation of process parameters and properties of TiO2 films grown by ion beam sputter deposition from a ceramic target

NASA Astrophysics Data System (ADS)

Bundesmann, Carsten; Lautenschläge, Thomas; Spemann, Daniel; Finzel, Annemarie; Mensing, Michael; Frost, Frank

2017-10-01

The correlation between process parameters and properties of TiO2 films grown by ion beam sputter deposition from a ceramic target was investigated. TiO2 films were grown under systematic variation of ion beam parameters (ion species, ion energy) and geometrical parameters (ion incidence angle, polar emission angle) and characterized with respect to film thickness, growth rate, structural properties, surface topography, composition, optical properties, and mass density. Systematic variations of film properties with the scattering geometry, namely the scattering angle, have been revealed. There are also considerable differences in film properties when changing the process gas from Ar to Xe. Similar systematics were reported for TiO2 films grown by reactive ion beam sputter deposition from a metal target [C. Bundesmann et al., Appl. Surf. Sci. 421, 331 (2017)]. However, there are some deviations from the previously reported data, for instance, in growth rate, mass density and optical properties.

Increasing light coupling in a photovoltaic film by tuning nanoparticle shape with substrate surface energy

NASA Astrophysics Data System (ADS)

Kataria, Devika; Krishnamoorthy, Kothandam; Iyer, S. Sundar Kumar

2017-08-01

Tuning metal nanoparticle (MNP) contact angle on the surface it is formed can help maximise the useful optical coupling in photovoltaic films by localized surface plasmon (LSP) resonance—opening up the possibility of building improved photovoltaic cells. In this work experimental demonstration of optical absorption increase in copper phthalocyanine (CuPc) films by tuning silver MNP shape by changing its contact angles with substrate has been reported. Thin films of poly3,4 ethylenedioxythiophene: sodium dodecycl sulphate (PEDOT:SDS) with different surface energies were formed on indium tin oxide (ITO) coated glass by electro-deposition. Silver MNPs thermally evaporated directly on ozonised ITO as well as on the PEDOT:SDS films showed contact angles ranging from 60° to 125°. The CuPc layer was deposited on top of the MNPs. For the samples studied, best optical absorption in the CuPc layer was for a contact angle of 110°.

Properties of RF sputtered cadmium telluride (CdTe) thin films: Influence of deposition pressure

NASA Astrophysics Data System (ADS)

Kulkarni, R. R.; Pawbake, A. S.; Waykar, R. G.; Rondiya, S. R.; Jadhavar, A. A.; Pandharkar, S. M.; Karpe, S. D.; Diwate, K. D.; Jadkar, S. R.

2016-04-01

Influence of deposition pressure on structural, morphology, electrical and optical properties of CdTe thin films deposited at low substrate temperature (100°C) by RF magnetron sputtering was investigated. The formation of CdTe was confirmed by low angle XRD and Raman spectroscopy. The low angle XRD analysis revealed that the CdTe films have zinc blende (cubic) structure with crystallites having preferred orientation in (111) direction. Raman spectra show the longitudinal optical (LO) phonon mode peak ˜ 165.4 cm-1 suggesting high quality CdTe film were obtained over the entire range of deposition pressure studied. Scanning electron microscopy analysis showed that films are smooth, homogenous, and crack-free with no evidence of voids. The EDAX data revealed that CdTe films deposited at low deposition pressure are high-quality stoichiometric. However, for all deposition pressures, films are rich in Cd relative to Te. The UV-Visible spectroscopy analysis show the blue shift in absorption edge with increasing the deposition pressure while the band gap show decreasing trend. The highest electrical conductivity was obtained for the film deposited at deposition pressure 1 Pa which indicates that the optimized deposition pressure for our sputtering unit is 1 Pa. Based on the experimental results, these CdTe films can be useful for the application in the flexible solar cells and other opto-electronic devices.

Atomic layer deposition as pore diameter adjustment tool for nanoporous aluminum oxide injection molding masks.

PubMed

Miikkulainen, Ville; Rasilainen, Tiina; Puukilainen, Esa; Suvanto, Mika; Pakkanen, Tapani A

2008-05-06

The wetting properties of polypropylene (PP) surfaces were modified by adjusting the dimensions of the surface nanostructure. The nanostructures were generated by injection molding with nanoporous anodized aluminum oxide (AAO) as the mold insert. Atomic layer deposition (ALD) of molybdenum nitride film was used to control the pore diameters of the AAO inserts. The original 50-nm pore diameter of AAO was adjusted by depositing films of thickness 5, 10, and 15 nm on AAO. Bis(tert-butylimido)-bis(dimethylamido)molybdenum and ammonia were used as precursors in deposition. The resulting pore diameters in the nitride-coated AAO inserts were 40, 30, and 20 nm, respectively. Injection molding of PP was conducted with the coated inserts, as well as with the non-coated insert. Besides the pore diameter, the injection mold temperature was varied with temperatures of 50, 70, and 90 degrees C tested. Water contact angles of PP casts were measured and compared with theoretical contact angles calculated from Wenzel and Cassie-Baxter theories. The highest contact angle, 140 degrees , was observed for PP molded with the AAO mold insert with 30-nm pore diameter. The Cassie-Baxter theory showed better fit than the Wenzel theory to the experimental values. With the optimal AAO mask, the nanofeatures in the molded PP pieces were 100 nm high. In explanation of this finding, it is suggested that some sticking and stretching of the nanofeatures occurs during the molding. Increase in the mold temperature increased the contact angle.

Characteristic angles in the wetting of an angular region: deposit growth.

PubMed

Popov, Yuri O; Witten, Thomas A

2003-09-01

Solids dispersed in a drying drop migrate to the (pinned) contact line. This migration is caused by outward flows driven by the loss of the solvent due to evaporation and by geometrical constraint that the drop maintains an equilibrium surface shape with a fixed boundary. Here, in continuation of our earlier paper, we theoretically investigate the evaporation rate, the flow field, and the rate of growth of the deposit patterns in a drop over an angular sector on a plane substrate. Asymptotic power laws near the vertex (as distance to the vertex goes to zero) are obtained. A hydrodynamic model of fluid flow near the singularity of the vertex is developed and the velocity field is obtained. The rate of the deposit growth near the contact line is found in two time regimes. The deposited mass falls off as a weak power gamma of distance close to the vertex and as a stronger power beta of distance further from the vertex. The power gamma depends only slightly on the opening angle alpha and stays roughly between -1/3 and 0. The power beta varies from -1 to 0 as the opening angle increases from 0 degrees to 180 degrees. At a given distance from the vertex, the deposited mass grows faster and faster with time, with the greatest increase in the growth rate occurring at the early stages of the drying process.

Pore-scale distribution of mucilage affecting water repellency in the rhizosphere

NASA Astrophysics Data System (ADS)

Benard, Pascal; Zarebanadkouki, Mohsen; Hedwig, Clemens; Holz, Maire; Ahmed, Mutez; Carminati, Andrea

2017-04-01

The hydraulic properties of the rhizosphere are altered by plants, fungi and microorganism. Plant roots release different compounds into the soil. One of these substances is mucilage, a gel which turns water repellent upon drying. We introduce a conceptual model of mucilage deposition during soil drying and its impact on the soil wettability. As the soil dries, water menisci recede and draw mucilage towards the contact region between particles where it is deposited. At high mucilage content, mucilage deposits expand into the open pore space and finally block water infiltration when a critical fraction of the pore space is blocked. To test this hypothesis, we mixed mucilage and particles of different grain size, we let them dry and measured the contact angle using the sessile drop method. Mucilage deposition was visualized by light microscopy imaging. Contact angle measurements showed a distinct threshold-like behavior with a sudden increase in apparent contact angle at high mucilage concentrations. Particle roughness induced a more uniform distribution of mucilage. The observed threshold corresponds to the concentration when mucilage deposition occupies a critical fraction of the pore space, as visualized with the microscope images. In conclusion, water repellency is critically affected by the distribution of mucilage on the pore-scale. This microscopic heterogeneity has to be taken into account in the description of macroscopic processes, like water infiltration or rewetting of water repellent soil.

Gold nanoparticles deposited on glass: physicochemical characterization and cytocompatibility

PubMed Central

2013-01-01

Properties of gold films sputtered under different conditions onto borosilicate glass substrate were studied. Mean thickness of sputtered gold film was measured by gravimetry, and film contact angle was determined by goniometry. Surface morphology was examined by atomic force microscopy, and electrical sheet resistance was determined by two-point technique. The samples were seeded with rat vascular smooth muscle cells, and their adhesion and proliferation were studied. Gold depositions lead to dramatical changes in the surface morphology and roughness in comparison to pristine substrate. For sputtered gold structures, the rapid decline of the sheet resistance appears on structures deposited for the times above 100 s. The thickness of deposited gold nanoparticles/layer is an increasing function of sputtering time and current. AFM images prove the creation of separated gold islands in the initial deposition phase and a continuous gold coverage for longer deposition times. Gold deposition has a positive effect on the proliferation of vascular smooth muscle cells. Largest number of cells was observed on sample sputtered with gold for 20 s and at the discharge current of 40 mA. This sample exhibits lowest contact angle, low relative roughness, and only mild increase of electrical conductivity. PMID:23705782

Growth Assisted by Glancing Angle Deposition: A New Technique to Fabricate Highly Porous Anisotropic Thin Films.

PubMed

Sanchez-Valencia, Juan Ramon; Longtin, Remi; Rossell, Marta D; Gröning, Pierangelo

2016-04-06

We report a new methodology based on glancing angle deposition (GLAD) of an organic molecule in combination with perpendicular growth of a second inorganic material. The resulting thin films retain a very well-defined tilted columnar microstructure characteristic of GLAD with the inorganic material embedded inside the columns. We refer to this new methodology as growth assisted by glancing angle deposition or GAGLAD, since the material of interest (here, the inorganic) grows in the form of tilted columns, though it is deposited under a nonglancing configuration. As a "proof of concept", we have used silver and zinc oxide as the perpendicularly deposited material since they usually form ill-defined columnar microstructures at room temperature by GLAD. By means of our GAGLAD methodology, the typical tilted columnar microstructure can be developed for materials that otherwise do not form ordered structures under conventional GLAD. This simple methodology broadens significantly the range of materials where control of the microstructure can be achieved by tuning the geometrical deposition parameters. The two examples presented here, Ag/Alq3 and ZnO/Alq3, have been deposited by physical vapor deposition (PVD) and plasma enhanced chemical vapor deposition (PECVD), respectively: two different vacuum techniques that illustrate the generality of the proposed technique. The two type of hybrid samples present very interesting properties that demonstrate the potentiality of GAGLAD. On one hand, the Ag/Alq3 samples present highly optical anisotropic properties when they are analyzed with linearly polarized light. To our knowledge, these Ag/Alq3 samples present the highest angular selectivity reported in the visible range. On the other hand, ZnO/Alq3 samples are used to develop highly porous ZnO thin films by using Alq3 as sacrificial material. In this way, antireflective ZnO samples with very low refractive index and extinction coefficient have been obtained.

Computational fluid dynamics (CFD) simulation of a newly designed passive particle sampler.

PubMed

Sajjadi, H; Tavakoli, B; Ahmadi, G; Dhaniyala, S; Harner, T; Holsen, T M

2016-07-01

In this work a series of computational fluid dynamics (CFD) simulations were performed to predict the deposition of particles on a newly designed passive dry deposition (Pas-DD) sampler. The sampler uses a parallel plate design and a conventional polyurethane foam (PUF) disk as the deposition surface. The deposition of particles with sizes between 0.5 and 10 μm was investigated for two different geometries of the Pas-DD sampler for different wind speeds and various angles of attack. To evaluate the mean flow field, the k-ɛ turbulence model was used and turbulent fluctuating velocities were generated using the discrete random walk (DRW) model. The CFD software ANSYS-FLUENT was used for performing the numerical simulations. It was found that the deposition velocity increased with particle size or wind speed. The modeled deposition velocities were in general agreement with the experimental measurements and they increased when flow entered the sampler with a non-zero angle of attack. The particle-size dependent deposition velocity was also dependent on the geometry of the leading edge of the sampler; deposition velocities were more dependent on particle size and wind speeds for the sampler without the bend in the leading edge of the deposition plate, compared to a flat plate design. Foam roughness was also found to have a small impact on particle deposition. Copyright © 2016 Elsevier Ltd. All rights reserved.

Freeform Deposition Method for Coolant Channel Closeout

NASA Technical Reports Server (NTRS)

Gradl, Paul R. (Inventor); Reynolds, David Christopher (Inventor); Walker, Bryant H. (Inventor)

2017-01-01

A method is provided for fabricating a coolant channel closeout jacket on a structure having coolant channels formed in an outer surface thereof. A line of tangency relative to the outer surface is defined for each point on the outer surface. Linear rows of a metal feedstock are directed towards and deposited on the outer surface of the structure as a beam of weld energy is directed to the metal feedstock so-deposited. A first angle between the metal feedstock so-directed and the line of tangency is maintained in a range of 20-90.degree.. The beam is directed towards a portion of the linear rows such that less than 30% of the cross-sectional area of the beam impinges on a currently-deposited one of the linear rows. A second angle between the beam and the line of tangency is maintained in a range of 5-65 degrees.

Study of structural and optical properties of ZnS zigzag nanostructured thin films

NASA Astrophysics Data System (ADS)

Rahchamani, Seyyed Zabihollah; Rezagholipour Dizaji, Hamid; Ehsani, Mohammad Hossein

2015-11-01

Zinc sulfide (ZnS) nanostructured thin films of different thicknesses with zigzag shapes have been deposited on glass substrates by glancing angle deposition (GLAD) technique. Employing a homemade accessory attached to the substrate holder enabled the authors to control the substrate temperature and substrate angle. The prepared samples were subjected to X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM) and UV-VIS. spectroscopy techniques. The structural studies revealed that the film deposited at room temperature crystallized in cubic structure. The FESEM images of the samples confirmed the formation of zigzag nano-columnar shape with mean diameter about 60-80 nm. By using the data obtained from optical studies, the real part of the refractive index (n), the absorption coefficient (α) and the band gap (Eg) of the samples were calculated. The results show that the refractive indices of the prepared films are very sensitive to deposition conditions.

Glancing-angle-deposited magnesium oxide films for high-fluence applications

DOE PAGES

Oliver, J. B.; Smith, C.; Spaulding, J.; ...

2016-06-15

Here, Birefringent magnesium oxide thin films are formed by glancing angle deposition to perform as quarter-wave plates at a wavelength of 351 nm. These films are being developed to fabricate a large aperture distributed-polarization rotator for use in vacuum, with an ultimate laser-damage–threshold goal of up to 12 J/cm 2 for a 5-ns flat-in-time pulse. The laser-damage threshold, ease of deposition, and optical film properties are evaluated. While the measured large-area laser-damage threshold is limited to ~4 J/cm 2 in vacuum, initial results based on small-spot testing in air (>20 J/cm 2) suggest MgO may be suitable with further processmore » development.« less

Development of Mainshaft High-Speed Cylindrical Roller Bearings for Gas Turbine Engines.

DTIC Science & Technology

1978-10-01

roller motion, that calculation may then be eliminated for subsequent, similar runs. TIhis option provides the user a corresponding savings in computer...to W BEARING DN X !0.6 Figl"re 2..’ Test of Grou p-N Bearing No, ,5 Shows" Increased Skid as l~oad Is N" l)’creans4’d but With No Skid at Anyt Loand

Integration of Instrumentation for Measuring Vital Signs

DTIC Science & Technology

1992-10-31

integrated product. D. NON INVASIVE BLOOD PRESSURE (NIBP) As mentioned above SpaceLabe measures NIBP using oscillometry . They also make an ambulatory ,,nit...that works with a small cuff inflated periodically by a miniature compressor, where detection is again by oscillometry . Invivo Research markets an AC...Battery operated unit that also uses oscillometry . Ohmeda has developed the Flnapres unit that uses tho principal of arterial un!oading. In this scheme a

United States Air Force Statistical Digest, Fiscal Year 1954. Ninth Edition

DTIC Science & Technology

1954-09-30

expenditure frOm the Treasury. In Budget_ Treasury Regulation 1, appropriation accounts include not only accounts to which money is directly...services received or assets acquired for vhich payment has been oade. Synonymous with disbursements less expenditure refunds. (AFM 170-3) FUND A sum of money ...during a given period reqUiring future payment of money . PROJECT ACCOUNr CLASSIFICATION In appropriation and fund accounting, an approved system of

[Effectivity and security of vildagliptin as additional treatment for Type 2 diabetes mellitus in real-life conditions in Mexico. EDGE Study subanalysis].

PubMed

Márquez-Rodríguez, Eduardo; Brea-Andrea, Eduardo; Rajmet-Hace, Victoria Alejandro; Salinas-Salinas, Javier; Mariño-Rojas, Fabiola

2016-01-01

The multinational EDGE (Effectiveness of Diabetes control with vildaGliptin and vildagliptin/mEtformin) study assessed the effectiveness and tolerability of vildagliptin versus other oral antihyperglycemic drugs (OAD) when added to monotherapy in patients in the real-world setting. Prospective, real-world observational study. The primary endpoint (PEP) was the proportion of patients achieving a reduction in HbA1c > 0.3% without peripheral edema, hypoglycemia, discontinuation, dueto gastrointestinal event, or weight gain > 5%. The secondary endpoint (SEP) was the proportion of patient achieving HbA1c < 7% (at month 12), without proven hypoglycemia or weight gain (≥ 3%). Of the 3,523 patients enrolled in Mexico, 2,847 were in the vildagliptin and 676 in the comparator cohort. The PEP was reached in 61.8 and 53.2% in the vildagliptin and comparator cohorts, respectively. The unadjusted odds ratio was 1.42 (95% CI: 1.19-1.68) in favor of vildagliptin. A similar advantage for vildagliptin-based therapies was seen for the SEP. The percentage was lower in the vildagliptin (n = 145; 5.0%) than in the comparator group (n = 95; 14.0%). Vildagliptin, added to a first-line OAD monotherapy, allows patients to reach target HbA1c without experiencing significant adverse events.

Platinum nanocatalysts prepared with different surfactants for C1-C3 alcohol oxidations and their surface morphologies by AFM

NASA Astrophysics Data System (ADS)

Ertan, Salih; Şen, Fatih; Şen, Selda; Gökağaç, Gülsün

2012-06-01

In this study, platinum nanoparticle catalysts have been prepared using PtCl4 as a starting material and 1-octanethiol, 1-decanethiol, 1-dodecanethiol, and 1-hexadecanethiol as surfactants for methanol, ethanol, and 2-propanol oxidation reactions. The structure, particle sizes, and surface morphologies of the catalysts were characterized by X-ray diffraction (XRD), atomic force microscopy and transmission electron microscopy (TEM). XRD and TEM results indicate that all prepared catalysts have a face-centered cubic structure and are homogeneously dispersed on the carbon support with a narrow size distribution (2.0-1.3 nm). X-ray photoelectron spectra of the catalysts were examined and it is found that platinum has two different oxidation states, Pt (0) and Pt(IV), oxygen and sulfur compounds are H2Oads and OHads, bound and unbound thiols. The electrochemical and electrocatalytic properties of these catalysts were investigated with respect to C1-C3 alcohol oxidations by cyclic voltammetry and chronoamperometry. The highest electrocatalytic activity was obtained from catalyst I which was prepared with 1-octanethiol. This may be attributed to a decrease in the ratio of bound to unbound thiol species increase in Pt (0)/Pt(IV), H2Oads/OHads ratios, electrochemical surface area, CO tolerance and percent platinum utility.

Ion beam sputtering of Ag - Angular and energetic distributions of sputtered and scattered particles

NASA Astrophysics Data System (ADS)

Feder, René; Bundesmann, Carsten; Neumann, Horst; Rauschenbach, Bernd

2013-12-01

Ion beam sputter deposition (IBD) provides intrinsic features which influence the properties of the growing film, because ion properties and geometrical process conditions generate different energy and spatial distribution of the sputtered and scattered particles. A vacuum deposition chamber is set up to measure the energy and spatial distribution of secondary particles produced by ion beam sputtering of different target materials under variation of geometrical parameters (incidence angle of primary ions and emission angle of secondary particles) and of primary ion beam parameters (ion species and energies).

Method for preparing high temperature superconductor

DOEpatents

Balachandran, Uthamalingam; Chudzik, Michael P.

2002-01-01

A method of depositing a biaxially textured metal oxide on a substrate defining a plane in which metal oxide atoms are vaporized from a source to form a plume of metal oxide atoms. Atoms in the plume disposed at a selected angle in a predetermined range of angles to the plane of the substrate are allowed to contact the substrate while preventing atoms outside a selected angle from reaching the substrate. The preferred range of angles is 40.degree.-70.degree. and the preferred angle is 60.degree..+-.5.degree.. A moving substrate is disclosed.

Broadband and wide-angle distributed Bragg reflectors based on amorphous germanium films by glancing angle deposition.

PubMed

Leem, Jung Woo; Yu, Jae Su

2012-08-27

We fabricated the distributed Bragg reflectors (DBRs) with amorphous germanium (a-Ge) films consisted of the same materials at a center wavelength (λc) of 1.33 μm by the glancing angle deposition. Their optical reflectance properties were investigated in the infrared wavelength region of 1-1.9 μm at incident light angles (θ inc) of 8-70°, together with the theoretical analysis using a rigorous coupled-wave analysis simulation. The two alternating a-Ge films at the incident vapor flux angles of 0 and 75° were formed as the high and low refractive index materials, respectively. The a-Ge DBR with only 5 periods exhibited a normalized stop bandwidth (∆λ/λ c) of ~24.1%, maintaining high reflectance (R) values of > 99%. Even at a high θ inc of 70°, the ∆λ/λ c was ~21.9%, maintaining R values of > 85%. The a-Ge DBR with good uniformity was obtained over the area of a 2 inch Si wafer. The calculated reflectance results showed a similar tendency to the measured data.

Surface Finish after Laser Metal Deposition

NASA Astrophysics Data System (ADS)

Rombouts, M.; Maes, G.; Hendrix, W.; Delarbre, E.; Motmans, F.

Laser metal deposition (LMD) is an additive manufacturing technology for the fabrication of metal parts through layerwise deposition and laser induced melting of metal powder. The poor surface finish presents a major limitation in LMD. This study focuses on the effects of surface inclination angle and strategies to improve the surface finish of LMD components. A substantial improvement in surface quality of both the side and top surfaces has been obtained by laser remelting after powder deposition.

Beam impingement angle effects on secondary electron emission characteristics of textured pyrolytic graphite

NASA Technical Reports Server (NTRS)

Curren, A. N.; Jensen, K. A.

1984-01-01

Experimentally determined values of true secondary electron emission and relative values of reflected primary electron yield for untreated and ion-textured pyrolytic graphite over a range of primary electron energy levels and electron beam impingement angles are presented. Information required to develop high efficiency multistage depressed collectors (MDC's) for microwave amplifier traveling-wave tubes for space communication and aircraft applications is provided. To attain the highest possible MDC efficiencies, the electrode surfaces must have low secondary electron emission characteristics. Pyrolytic graphite, a chemically vapor-deposited material, is a particularly promising candidate for this application. The pyrolytic graphite surfaces studied were tested over a range of primary electron beam energies and beam impingement angles from 200 to 2000 eV and direct (0 deg) to near-grazing angles (85 deg), respectively. Surfaces both parallel to and normal to the planes of material deposition were examined. The true secondary electron emission and reflected primary electron yield characteristics of the pyrolytic graphite surfaces are compared to those of sooted control surfaces.

Electrical transport in AZO nanorods

NASA Astrophysics Data System (ADS)

Yildiz, A.; Cansizoglu, H.; Karabacak, T.

2015-10-01

Al-doped ZnO (AZO) nanorods (NRs) with different lengths were deposited by utilizing glancing angle deposition (GLAD) technique in a DC sputter system at room temperature. The structural and optical characteristics of the NRs were investigated by the X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV-vis-NIR spectroscopy measurements. A band gap of about 3.5 eV was observed for the NRs. A novel capping process utilizing varying deposition angles was used to introduce a blanket metal top contact for the electrical characterization of NRs. Current-voltage (I-V) measurements were used to properly evaluate the approximate resistivity of a single NR. The electrical conduction was found to be governed by the thermally activated transport mechanism. Activation energy was determined as 0.14 eV from temperature dependent resistivity data.

Glancing angle deposition of sculptured thin metal films at room temperature

NASA Astrophysics Data System (ADS)

Liedtke, S.; Grüner, Ch; Lotnyk, A.; Rauschenbach, B.

2017-09-01

Metallic thin films consisting of separated nanostructures are fabricated by evaporative glancing angle deposition at room temperature. The columnar microstructure of the Ti and Cr columns is investigated by high resolution transmission electron microscopy and selective area electron diffraction. The morphology of the sculptured metallic films is studied by scanning electron microscopy. It is found that tilted Ti and Cr columns grow with a single crystalline morphology, while upright Cr columns are polycrystalline. Further, the influence of continuous substrate rotation on the shaping of Al, Ti, Cr and Mo nanostructures is studied with view to surface diffusion and the shadowing effect. It is observed that sculptured metallic thin films deposited without substrate rotation grow faster compared to those grown with continuous substrate rotation. A theoretical model is provided to describe this effect.

Effects of annealing on arrays of Ge nanocolumns formed by glancing angle deposition

NASA Astrophysics Data System (ADS)

Khare, C.; Gerlach, J. W.; Höche, T.; Fuhrmann, B.; Leipner, H. S.; Rauschenbach, B.

2012-10-01

Post-deposition thermal annealing of glancing angle deposited Ge nanocolumn arrays was carried out in a continuous Ar-flow at temperatures ranging from TA = 300 to 800 °C for different annealing durations. Morphological alterations and the recrystallization process induced by the thermal annealing treatment were investigated for the Ge nanocolumns deposited on planar and pre-patterned Si substrates. From X-ray diffraction (XRD) measurements, the films annealed at TA ≥ 500 °C were found to be polycrystalline. On planar Si substrates, at TA = 600 °C nanocolumns exhibited strong coarsening and merging, while a complete disintegration of the nanocolumns was detected at TA = 700 °C. The morphology of nanostructures deposited on pre-patterned substrates differs substantially, where the merging or column-disintegration effect was absent at elevated annealing temperatures. The two-arm-chevron nanostructures grown on pre-patterned substrates retained their complex shape and morphology, after extended annealing intervals. Investigations by transmission electron microscopy revealed nanocrystalline domains of the order of 5-30 nm (in diameter) present within the chevron structures after the annealing treatment.

Reduced atomic shadowing in HiPIMS: Role of the thermalized metal ions

NASA Astrophysics Data System (ADS)

Oliveira, João Carlos; Ferreira, Fábio; Anders, André; Cavaleiro, Albano

2018-03-01

In magnetron sputtering, the ability to tailor film properties depends primarily on the control of the flux of particles impinging on the growing film. Among deposition mechanisms, the shadowing effect leads to the formation of a rough surface and a porous, columnar microstructure. Re-sputtered species may be re-deposited in the valleys of the films surface and thereby contribute to a reduction of roughness and to fill the underdense regions. Both effects are non-local and they directly compete to shape the final properties of the deposited films. Additional control of the bombarding flux can be obtained by ionizing the sputtered flux, because ions can be controlled with respect to their energy and impinging direction, such as in High-Power Impulse Magnetron Sputtering (HiPIMS). In this work, the relation between ionization of the sputtered species and thin film properties is investigated in order to identify the mechanisms which effectively influence the shadowing effect in Deep Oscillation Magnetron Sputtering (DOMS), a variant of HiPIMS. The properties of two Cr films deposited using the same averaged target power by d.c. magnetron sputtering and DOMS have been compared. Additionally, the angle distribution of the Cr species impinging on the substrate was simulated using Monte Carlo-based programs while the energy distribution of the energetic particles bombarding the substrate was evaluated by energy-resolved mass analysis. It was found that the acceleration of the thermalized chromium ions at the substrate sheath in DOMS significantly reduces the high angle component of their impinging angle distribution and, thus, efficiently reduces atomic shadowing. Therefore, a high degree of ionization in HiPIMS results in almost shadowing effect-free film deposition and allows us to deposit dense and compact films without the need of high energy particle bombardment during growth.

Densely packed aluminum-silver nanohelices as an ultra-thin perfect light absorber

PubMed Central

Jen, Yi-Jun; Huang, Yu-Jie; Liu, Wei-Chih; Lin, Yueh Weng

2017-01-01

Metals have been formed into nanostructures to absorb light with high efficiency through surface plasmon resonances. An ultra-thin plasmonic structure that exhibits strong absorption over wide ranges of wavelengths and angles of incidence is sought. In this work, a nearly perfect plasmonic nanostructure is fabricated using glancing angle deposition. The difference between the morphologies of obliquely deposited aluminum and silver nanohelices is exploited to form a novel three-dimensional structure, which is an aluminum-silver nanohelix array on a pattern-free substrate. With a thickness of only 470 nm, densely distributed nanohelices support rod-to-rod localized surface plasmons for broadband and polarization-independent light extinction. The extinctance remains high over wavelengths from 400 nm to 2000 nm and angles of incidence from 0° to 70°. PMID:28045135

Superhydrophobic ceramic coating: Fabrication by solution precursor plasma spray and investigation of wetting behavior.

PubMed

Xu, Pengyun; Coyle, Thomas W; Pershin, Larry; Mostaghimi, Javad

2018-08-01

Superhydrophobic surfaces are often created by fabricating suitable surface structures from low-surface-energy organic materials using processes that are not suitable for large-scale fabrication. Rare earth oxides (REO) exhibit hydrophobic behavior that is unusual among oxides. Solution precursor plasma spray (SPPS) deposition is a rapid, one-step process that can produce ceramic coatings with fine scale columnar structures. Manipulation of the structure of REO coatings through variation in deposition conditions may allow the wetting behavior to be controlled. Yb 2 O 3 coatings were fabricated via SPPS. Coating structure was investigated by scanning electron microscopy, digital optical microscopy, and x-ray diffraction. The static water contact angle and roll-off angle were measured, and the dynamic impact of water droplets on the coating surface recorded. Superhydrophobic behavior was observed; the best coating exhibited a water contact angle of ∼163°, a roll-off angle of ∼6°, and complete droplet rebound behavior. All coatings were crystalline Yb 2 O 3 , with a nano-scale roughness superimposed on a micron-scale columnar structure. The wetting behaviors of coatings deposited at different standoff distances were correlated with the coating microstructures and surface topographies. The self-cleaning, water flushing and water jetting tests were conducted and further demonstrated the excellent and durable hydrophobicity of the coatings. Copyright © 2018 Elsevier Inc. All rights reserved.

Ag-Cu mixed phase plasmonic nanostructures fabricated by shadow nanosphere lithography and glancing angle co-deposition

NASA Astrophysics Data System (ADS)

Ingram, Whitney; Larson, Steven; Carlson, Daniel; Zhao, Yiping

2017-01-01

By combining shadow nanosphere lithography with a glancing angle co-deposition technique, mixed-phase Ag-Cu triangular nanopatterns and films were fabricated. They were prepared at different compositions with respect to Ag from 100% to 0% by changing the relative deposition ratio of each metal. Characterizations by ellipsometry, energy dispersive x-ray spectroscopy, and x-ray diffraction revealed that the thin films and nanopatterns were composed of small, well-mixed Ag and Cu nano-grains with a diameter less than 20 nm, and their optical properties could be described by an effective medium theory. All compositions of the nanopattern had the same shape, but showed tunable localized surface plasmon resonance (LSPR) properties. In general, the LSPR of the nanopatterns redshifted with decreasing composition. Such a relation could be fitted by an empirical model based on the bulk theory of alloy plasmonics. By changing the colloidal template and the material deposited, this fabrication technique can be used to produce other alloy plasmonic nanostructures with predicted LSPR wavelengths.

Ag-Cu mixed phase plasmonic nanostructures fabricated by shadow nanosphere lithography and glancing angle co-deposition.

PubMed

Ingram, Whitney; Larson, Steven; Carlson, Daniel; Zhao, Yiping

2017-01-06

By combining shadow nanosphere lithography with a glancing angle co-deposition technique, mixed-phase Ag-Cu triangular nanopatterns and films were fabricated. They were prepared at different compositions with respect to Ag from 100% to 0% by changing the relative deposition ratio of each metal. Characterizations by ellipsometry, energy dispersive x-ray spectroscopy, and x-ray diffraction revealed that the thin films and nanopatterns were composed of small, well-mixed Ag and Cu nano-grains with a diameter less than 20 nm, and their optical properties could be described by an effective medium theory. All compositions of the nanopattern had the same shape, but showed tunable localized surface plasmon resonance (LSPR) properties. In general, the LSPR of the nanopatterns redshifted with decreasing composition. Such a relation could be fitted by an empirical model based on the bulk theory of alloy plasmonics. By changing the colloidal template and the material deposited, this fabrication technique can be used to produce other alloy plasmonic nanostructures with predicted LSPR wavelengths.

Ternary graphene/amorphous carbon/nickel nanocomposite film for outstanding superhydrophobicity

NASA Astrophysics Data System (ADS)

Zhu, Xiaobo; Zhou, Shengguo; Yan, Qingqing

2018-04-01

A novel superhydrophobic ternary graphene/amorphous carbon/nickel (G-Ni/a-C:H) carbon-based film was fabricated by a green approach of high-voltage electrochemical deposition without using aqueous solution, which was systematically investigated including the structure and relating applications on self-cleaning and corrosion resistance. Graphene and nickel nano-particle inserts were effective to tailor the feature of nanocrystallite/amorphous microstructure as well as micro-nanoscale hierarchical rose-petal-like surface for G-Ni/a-C:H carbon-based film. Surprisingly, this deposit could present outstanding superhydrophobicity with the contact angle of 158.98 deg and sliding angle of 2.75 deg without any further surface modification meanwhile it could possess fairly well adhesion. Furthermore, the superhydrophobic G-Ni/a-C:H carbon-based film could exhibit excellent corrosion resistance and self-cleaning performances compared to no graphene incorporated deposit. The procedure of fabricating deposit might be simple, scalable, and environmental friendly, indicating a promising prospect for industrial applications in the field of anti-fouling, anti-corrosion and drag resistance.

Field ion microscopic studies of the CO oxidation on platinum: Field ion imaging and titration reactions

NASA Astrophysics Data System (ADS)

Gorodetskii, V.; Drachsel, W.; Block, J. H.

1994-05-01

Elementary steps of the CO oxidation—which are important for understanding the oscillatory behavior of this catalytic reaction—are investigated simultaneously on different Pt-single crystal surfaces by field ion microscopy. Due to preferential ionization probabilities of oxygen as imaging gas on those surface sites, which are adsorbed with oxygen, these sites can be imaged in a lateral resolution on the atomic scale. In the titration reaction a COad-precovered field emitter surface reacts with gaseous oxygen adsorbed from the gas phase or, vice versa, the Oad-precovered surface with carbon monoxide adsorbed from the gas phase. The competition of the manifold of single crystal planes exposed to the titration reaction at the field emitter tip is studied. The surface specificity can be documented in the specific reaction delay times of the different planes and in the propagation rates of the reaction-diffusion wave fronts measured on these individual planes during the titration reaction with a time resolution of 40 ms. At 300 K the COad-precovered surfaces display the {011} regions, precisely the {331} planes as the most active, followed by {012}, {122}, {001}, and finally by {111}. Reaction wave fronts move with a velocity of 8 Å/s at {012}, with ≊0.8 Å/s at {111}, and have a very fast ``switch-on'' reaction at the (001) plane with 500 Å/s. At higher temperature, T=350 K, an acceleration of reaction rates is combined with shorter delay times. The titration reaction of a precovered Oad surface with COgas at T=373 K shows the formation of CO islands starting in the {011} regions with a quickly moving reaction front into the other surface areas without showing particular delay times for different surface symmetries. The two reverse titration reactions have a largely different character. The titration of COad with oxygen adsorbed from the gas phase consists of three different steps, (i) the induction times, (ii) the highly surface specific reaction, and (iii) different rates of wave front propagation. The reaction of COgas with a precovered Oad layer on the other hand starts with nucleating islands around the {011} planes from where the whole emitter surface is populated with COad without pronounced surface specifity.

Introducing a simplified approach to insulin therapy in type 2 diabetes: a comparison of two single-dose regimens of insulin glulisine plus insulin glargine and oral antidiabetic drugs.

PubMed

Lankisch, M R; Ferlinz, K C; Leahy, J L; Scherbaum, W A

2008-12-01

To investigate whether the addition of a single bolus of insulin glulisine (glulisine), administered at either breakfast or main mealtime, in combination with basal insulin glargine (glargine) and oral antidiabetic drugs (OADs), provides equivalent glycaemic control in patients with type 2 diabetes, irrespective of the time of glulisine injection. A national, multicentre, randomized, open-label, parallel-group study of 393 patients with type 2 diabetes who were suboptimally controlled [haemoglobin A(1c) (HbA(1c)) > 6.5-9.0% and fasting blood glucose (BG) 7.0% at baseline and who reached HbA(1c)

Efficacy and tolerability of vildagliptin-based versus comparative dual therapy in type 2 diabetes : Results of the Austrian subpopulation of the EDGE study.

PubMed

Brath, Helmut; Bialek, Christoph; Gingl, Ewald; Resl, Michael; Prager, Rudolf; Ratzinger, Michaela

2015-04-01

The aim of this post hoc analysis of data from the Austrian subpopulation of the EDGE study was the evaluation of the effectiveness and tolerability of vildagliptin as an add-on to an existing oral antidiabetic (OAD) monotherapy versus a combination therapy with two OADs without vildagliptin in patients with inadequately controlled type 2 diabetes. In Austria, 422 patients were included. In the framework of regular visits (at baseline, about once per quarter, and at the study end, after 12 months), adverse events (AEs), courses, and changes of therapy were recorded. In addition to the primary end point defined in the primary study, i.e., a reduction of HbA1c by > 0.3 % without hypoglycemia, weight gain ≥ 5 %, peripheral edema, or discontinuation due to gastrointestinal events, the most clinically relevant secondary end point, i.e., HbA1c reduction < 7 % without hypoglycemia or ≥ 3 % increase in body weight after 12 months was used for the analysis of the Austrian data. The initial HbA1c of all enrolled patients was 8.3 ± 1.4 %. The mean reduction of HbA1c was - 1.1 % in the vildagliptin cohort and - 1.0 % in the comparator cohort. In the vildagliptin cohort, 56.4 % of patients, and in the comparator cohort, 45.9 % of patients, reached the primary end point (odds ratio: 1.53, p = 0.04). In the vildagliptin cohort, 18.7 % of patients, and in the comparator cohort, 16.9 % of patients, reached the secondary end point (odds ratio: 1.13, p = 0.68). The incidence of hypoglycemic events (two in each cohort), AEs (approximately 15 % in each cohort), and serious AEs (approximately 2 % in each cohort) was comparable between the two groups. In a "real-life" setting, the effectiveness of vildagliptin as second-line treatment is superior to comparator OADs with regard to a reduction in HbA1c of greater than 0.3 % from baseline without well-recognized side effects in patients with inadequately controlled type 2 diabetes (mean baseline HbA1c: 8.5 % (vildagliptin cohort) vs. 8.1 % (comparator cohort)).

The efficacy of repaglinide monotherapy and in combination with metformin in Indonesian type 2 diabetes mellitus patients.

PubMed

Soegondo, Sidartawan; Subekti, Imam; Luthariana, Lies

2004-01-01

To investigate the efficacy and safety of repaglinide alone and in combination with metformin therapy. Seventy-two type 2 diabetes patients who were oral anti-diabetic drugs (OAD)-naive or currently on OAD for 7.0 mmol/L, it appeared that repaglinide alone at doses 0.5 or 1.0 mg achieved FBG <7.0 mmol/L in 67% of patients. The majority of the treatment emergent adverse events were mild and unlikely related to trial product. Episodes of symptomatic hypoglycaemia were low (9.3%) in frequency. The changes in haematology, clinical biochemistry and urinalysis were mostly minor or remained unchanged. Vital signs and the results of physical examination also remained unchanged. Three of the four withdrawals were due to adverse events but were unlikely related to trial product. treatment with repaglinide alone and in combination with metformin was efficacious in glycaemic control in OAD-naive or previous users. Most of the patients appeared to achieve good control with repaglinide alone. The treatment regimens were safe (317 words).

A Pilot Study to Compare Meal-Triggered Gastric Electrical Stimulation and Insulin Treatment in Chinese Obese Type 2 Diabetes

PubMed Central

Wong, Simon Kin-Hung; Kong, Alice Pik-Shan; Luk, Andrea On-Yan; Ozaki, Risa; Ng, Vanessa Wan-Sze; Lebovitz, Harold E.; Chan, Juliana Chung-Ngor

2015-01-01

Abstract Background: Gastrointestinal electromodulation therapy is a novel alternative for achieving diabetes control without traditional bariatric surgery. We compared the efficacy of a meal-initiated implantable gastric contractility modulation (GCM) device with that of insulin therapy in obese Chinese type 2 diabetes (T2D) patients, for whom oral antidiabetes drugs (OADs) had failed. Patients and Methods: Sixteen obese (body mass index, 27.5–40.0 kg/m2) T2D patients with a glycated hemoglobin (HbA1c) level of >7.5% on maximal doses of two or more OADs were offered either insulin therapy (n=8) or laparoscopic implantation of a GCM (n=8). We compared changes in body weight, waist circumference (WC), and HbA1c level 1 year after surgery. Results: The GCM and insulin groups had similar baseline body weight and HbA1c. At 12 months, body weight (−3.2±5.2 kg, P=0.043) and WC (−3.8±4.5 cm, P=0.021) fell in the GCM group but not in the insulin group (P<0.05 for between-group difference). At 6 and 12 months, the HbA1c level fell by 1.6±1.1% and 0.9±1.6% (P=0.011), compared with 0.6±0.3% and 0.6±0.3% (P=0.08) for the insulin group (P=0.15 for between-group difference). The mean 24-h systolic blood pressure (BP) fell by 4.5±1.0 mm Hg in the GCM group (P=0.017) but not in the insulin group. The GCM group required fewer antidiabetes medications (P<0.05) and BP-lowering drugs (P<0.05) than the insulin group. A subgroup analysis showed that patients with a triglyceride level of <1.7 mmol/L had a tendency toward a lower HbA1c level (P=0.090) compared with the controls. Conclusions: In obese T2D patients for whom OADs had failed, GCM implantation was a well-tolerated alternative to insulin therapy, with a low triglyceride level as a possible predictor for glycemic response. PMID:25710812

Enhancement on the Surface Hydrophobicity and Oleophobicity of an Organosilicon Film by Conformity Deposition and Surface Fluorination Etching.

PubMed

Xu, Zheng-Wen; Zhang, Yu-Kai; Chen, Tai-Hong; Chang, Jin-How; Lee, Tsung-Hsin; Li, Pei-Yu; Liu, Day-Shan

2018-06-26

In this work, the surface morphology of a hydrophobic organosilicon film was modified as it was deposited onto a silver seed layer with nanoparticles. The surface hydrophobicity evaluated by the water contact angle was significantly increased from 100° to 128° originating from the surface of the organosilicon film becoming roughened, and was deeply relevant to the Ag seed layer conform deposition. In addition, the organosilicon film became surface oleophobic and the surface hydrophobicity was improved due to the formation of the inactive C-F chemical on the surface after the carbon tetrafluoride glow discharge etching. The surface hydrophobicity and oleophobicity of the organosilicon film could be further optimized with water and oleic contact angles of about 138° and 61°, respectively, after an adequate fluorination etching.

Characterization of Mo/Si multilayer growth on stepped topographies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boogaard, A. J. R. vcan den; Louis, E.; Zoethout, E.

2011-08-31

Mo/Si multilayer mirrors with nanoscale bilayer thicknesses have been deposited on stepped substrate topographies, using various deposition angles. The multilayer morphology at the stepedge region was studied by cross section transmission electron microscopy. A transition from a continuous- to columnar layer morphology is observed near the step-edge, as a function of the local angle of incidence of the deposition flux. Taking into account the corresponding kinetics and anisotropy in layer growth, a continuum model has been developed to give a detailed description of the height profiles of the individual continuous layers. Complementary optical characterization of the multilayer system using amore » microscope operating in the extreme ultraviolet wavelength range, revealed that the influence of the step-edge on the planar multilayer structure is restricted to a region within 300 nm from the step-edge.« less

Brewster-angle 50%-50% beam splitter for p-polarized infrared light using a high-index quarter-wave layer deposited on a low-index prism.

PubMed

Azzam, R M A

2017-08-10

A quarter-wave layer (QWL) of high refractive index, which is deposited on a transparent prism of low refractive index, can be designed to split an incident p-polarized light beam at the Brewster angle (BA) of the air-substrate interface into p-polarized reflected and transmitted beams of equal intensity (50% each) that travel in orthogonal directions. For reflection of p-polarized light at the BA, the supported QWL functions as a free-standing (unsupported) pellicle. An exemplary design is presented that uses Si x Ge 1-x QWL deposited on an IRTRAN1 prism for applications (such as Michelson and Mach-Zehnder interferometry) with a variable compositional fraction x in the 2-6 μm mid-IR spectral range.

Stem cell behavior on tailored porous oxide surface coatings.

PubMed

Lavenus, Sandrine; Poxson, David J; Ogievetsky, Nika; Dordick, Jonathan S; Siegel, Richard W

2015-07-01

Nanoscale surface topographies are known to have a profound influence on cell behavior, including cell guidance, migration, morphology, proliferation, and differentiation. In this study, we have observed the behavior of human mesenchymal stem cells cultured on a range of tailored porous SiO2 and TiO2 nanostructured surface coatings fabricated via glancing angle electron-beam deposition. By controlling the physical vapor deposition angle during fabrication, we could control systematically the deposited coating porosity, along with associated topographic features. Immunocytochemistry and image analysis quantitatively revealed the number of adherent cells, as well as their basic cellular morphology, on these surfaces. Signaling pathway studies showed that even with subtle changes in nanoscale surface structures, the behavior of mesenchymal stem cells was strongly influenced by the precise surface structures of these porous coatings. Copyright © 2015 Elsevier Ltd. All rights reserved.

Development of porous metal oxide thin films by co-evaporation

NASA Astrophysics Data System (ADS)

Tesfamichael, T.; Motta, Nunzio; Bostrom, Thor; Bell, J. M.

2007-03-01

This paper focuses on the development of mixed metal oxide thin films and physical characterization of the films. The films were produced by co-evaporation of titanium oxide and tungsten oxide powders. This allowed the development of titanium oxide-tungsten oxide films as analyzed using XPS. Examination in the SEM and AFM showed that the films were nanoporous with the pore size and pore orientation varying as a function of the deposition angle. UV-vis spectra of the films show an increase of transmittance with increasing deposition angle which is attributed to the structure and porosity of the films. Raman analysis indicated that the as-deposited films have broad and weak Raman characteristics, attributed to the nanocrystal nature of the films and the presence of defects, and the peak broadening deceases after annealing the film, as expected.

T-Craft Seabase Ramp Loads Model Test Data Report

DTIC Science & Technology

2010-12-01

INTRODUCTION 1 TEST CONDITION MATRIX 2 MODEL DESCRIPTIONS 9 LMSR Model 15 Ramp Models 17 MODEL TEST SETUP 18 Side-by-Side Hull Configuration 19... INTRODUCTION The Office of Naval Research (ONR) sponsored a multiple bodied seakeeping model test designed to investigate vessel motions and loads on the hinge...C. 3. Side-by-Side configuration 137 Ramp Load cell 1.88 27.49 -CG ft I ^ -Hinged Connection 3.00 from CL to jauge • oad ce LMSR

The developmental association between eating disorders symptoms and symptoms of depression and anxiety in juvenile twin girls.

PubMed

Silberg, Judy L; Bulik, Cynthia M

2005-12-01

We investigated the role of genetic and environmental factors in the developmental association among symptoms of eating disorders, depression, and anxiety syndromes in 8-13-year-old and 14-17-year-old twin girls. Multivariate genetic models were fitted to child-reported longitudinal symptom data gathered from clinical interview on 408 MZ and 198 DZ female twin pairs from the Virginia Twin Study of Adolescent Behavioural Development (VTSABD). Model-fitting revealed distinct etiological patterns underlying the association among symptoms of eating disorders, depression, overanxious disorder (OAD), and separation anxiety disorder (SAD) during the course of development: 1) a common genetic factor influencing liability to all symptoms - of early and later OAD, depression, SAD, and eating symptoms; 2) a distinct genetic factor specifically indexing liability to early eating disorders symptoms; 3) a shared environmental factor specifically influencing early depression and early eating disorders symptoms; and 4) a common environmental factor affecting liability to symptoms of later eating disorders and both early and later separation anxiety. These results suggest a pervasive genetic effect that influences liability to symptoms of over-anxiety, separation anxiety, depression, and eating disorder throughout development, a shared environmental influence on later adolescent eating problems and persistent separation anxiety, genetic influences specific to early eating disorders symptoms, and a shared environmental factor influencing symptoms of early eating and depression.

Carbon-doped boron nitride nanosheet as a promising catalyst for N2O reduction by CO or SO2 molecule: A comparative DFT study

NASA Astrophysics Data System (ADS)

Esrafili, Mehdi D.; Saeidi, Nasibeh

2018-06-01

We report for the first time, the catalytic activity of the experimentally available carbon-doped boron nitride nanosheet (C-BNNS) towards the reduction of N2O in the presence of CO or SO2 molecule. According to our density functional theory calculations, C-doping can introduce high spin density into BN monolayer which is mainly localized over the C and its neighboring N atoms. The Hirshfeld charge density analysis reveals that the electron-rich C-BNNS acts as an electron donating support to activate N2O molecule which is an important step in the reduction of N2O. The N2O reduction reaction starts with the dissociative adsorption of N2O over the C-BNNS surface, yielding the N2 molecule and an activated oxygen moiety (Oads) adsorbed over the C atom. The reaction then proceeds via the elimination of Oads by a CO or SO2 molecule. The obtained low activation energies clearly indicate that the metal-free C-BNNS surface can be regarded as a highly active catalyst for the reduction of N2O. The results of this study may open new avenues in searching low cost and highly active BN-based catalysts for low temperature reduction of N2O.

The consumer welfare implications of governmental policies and firm strategy in markets for medicines.

PubMed

Chatterjee, Chirantan; Kubo, Kensuke; Pingali, Viswanath

2015-12-01

This paper empirically examines the consumer welfare implications of changes in government policies related to patent protection and compulsory licensing in the Indian market for oral anti-diabetic (OAD) medicines. In contrast to previous studies on the impact of pharmaceutical patents in India, we observe, and estimate the welfare effects accruing from differential pricing and voluntary licensing strategies of patent-holding innovator firms. Three novel molecules belonging to the dipeptidyl peptidase-4 (DPP-4) inhibitor class of OADs have been launched in India by the patent holders, at lower prices than those prevailing in the developed countries. Using aggregate market transaction data, we structurally estimate demand and supply and use the parameter estimates in our model to simulate consumer welfare under various counterfactual scenarios. Our results suggest that the introduction of DPP-4 inhibitors generated a consumer surplus gain of around 7.6 cents per day for a typical DPP-4 inhibitor user under the existing differential pricing and voluntary licensing strategies. If the innovators decide to price at developed-country levels, this surplus is eliminated almost entirely. The issuance of compulsory licensing does not always improve consumer welfare because if innovators defer or delay the introduction of new drugs in response, the loss in consumer welfare could be substantial. Copyright © 2015 Elsevier B.V. All rights reserved.

Gold coated metal nanostructures grown by glancing angle deposition and pulsed electroplating

NASA Astrophysics Data System (ADS)

Grüner, Christoph; Reeck, Pascal; Jacobs, Paul-Philipp; Liedtke, Susann; Lotnyk, Andriy; Rauschenbach, Bernd

2018-05-01

Nickel based nanostructures are grown by glancing angle deposition (GLAD) on flat and pre-patterned substrates. These fabricated porous thin films were subsequently coated by pulsed electroplating with gold. The morphology and conformity of the gold coating were investigated by scanning electron microscopy and X-ray diffraction. Controlled growth of closed gold layers on the nanostructures could be achieved, while the open-pore structure of the nanosculptured thin films was preserved. Such gold coated nanostructures are a candidate for optical sensing and catalysis applications. The demonstrated method can be applied for numerous material combinations, allowing to provide GLAD thin films with new surface properties.

Linear polarization-discriminatory state inverter fabricated by oblique angle deposition.

PubMed

Park, Yong Jun; Sobahan, K M A; Kim, Jin Joo; Hwangbo, Chang Kwon

2009-06-22

In this paper, we report a linear polarization-discriminatory state inverter made of three-layer sculpture thin film fabricated by oblique angle deposition technique. The first and third layers are quarter-wave plates of zigzag structure and the middle of them is a circular Bragg reflector of left-handed helical structure. It is found that the normal incidence of P-polarized light on this polarization-discriminatory state inverter becomes the S-polarized light at output, while the incident S-polarized light of wavelength lying in the Bragg regime is reflected. The microstructure of the linear polarization-discriminatory state inverter is also investigated by using a scanning electron microscope.

Topography and surface free energy of DPPC layers deposited on a glass, mica, or PMMA support.

PubMed

Jurak, Malgorzata; Chibowski, Emil

2006-08-15

An investigation of energetic properties of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) layers deposited on glass, mica, and PMMA (poly(methyl methacrylate)) surfaces was carried out by means of contact angles measurements (advancing and receding) for three probe liquids (diiodomethane, water, and formamide). DPPC was deposited on the surfaces from water (on glass and mica) or methanol (on PMMA) solutions. The topography of the tested surfaces was determined with a help of scanning electron microscopy (SEM) and atomic force microscopy (AFM). Using the measured contact angles, the total apparent surface free energy and its components of the studied layers were determined from van Oss et al.'s (Lifshitz-van der Waals and acid-base components, LWAB) and contact angle hysteresis (CAH) approaches. It allowed us to learn about changes in the surface free energy of the layers (hydrophobicity/hydrophilicity) depending on their number and kind of support. It was found that the changes in the energy greatly depended on the surface properties of the substrate as well as the statistical number of monolayers of DPPC. However, principal changes took place for first three monolayers.

Highly exothermic and superhydrophobic Mg/fluorocarbon core/shell nanoenergetic arrays.

PubMed

Zhou, Xiang; Xu, Daguo; Yang, Guangcheng; Zhang, Qiaobao; Shen, Jinpeng; Lu, Jian; Zhang, Kaili

2014-07-09

Mg/fluorocarbon core/shell nanoenergetic arrays are prepared onto silicon substrate, with Mg nanorods as the core and fluorocarbon as the shell. Mg nanorods are deposited by the glancing angle deposition technique, and the fluorocarbon layer is then prepared as a shell to encase the Mg nanorods by the magnetron sputtering deposition process. Scanning electron microscopy and transmission electron microscopy show the core/shell structure of the Mg/fluorocarbon arrays. X-ray energy-dispersive spectroscopy, X-ray diffraction, and Fourier transform infrared spectroscopy are used to characterize the structural composition of the Mg/fluorocarbon. It is found that the as-prepared fluorocarbon layer consists of shorter molecular chains compared to that of bulk polytetrafluoroethylene, which is proven beneficial to the low onset reaction temperature of Mg/fluorocarbon. Water contact angle test demonstrates the superhydrophobicity of the Mg/fluorocarbon arrays, and a static contact angle as high as 162° is achieved. Thermal analysis shows that the Mg/fluorocarbon material exhibits a very low onset reaction temperature of about 270 °C as well as an ultrahigh heat of reaction approaching 9 kJ/g. A preliminary combustion test reveals rapid combustion wave propagation, and a convective mechanism is adopted to explain the combustion behaviors.

Field characteristics of deposits from spatter-rich pyroclastic density currents at Summer Coon volcano, Colorado

NASA Astrophysics Data System (ADS)

Valentine, G. A.; Perry, F. V.; WoldeGabriel, G.

2000-12-01

The Oligocene, deeply eroded Summer Coon composite volcano contains mafic andesite deposits that are massive to poorly bedded, have abundant flattened and deformed spatter clasts, have varying proportions of dense lithic clasts, and are supported mostly by a coarse-ash matrix. Although superficially these deposits resemble typical facies from Strombolian eruptions (emplaced ballistically, by fallout, and by rolling and local grain-avalanches down steep cone slopes), there are several lines of evidence that lead to an interpretation that the deposits were emplaced by pyroclastic density currents. These include local coarse-tail grading, deformation of spatter clasts in a down-flow direction, incorporation of matrix ash and lapilli into flattened spatter clasts, imbrication of large clasts, plastering of spatter on stoss sides of large lithic blocks and lenses of lithic-rich material on lee sides, deposition on angles less than the angle of repose, and a paucity of clast shapes associated with Strombolian mechanisms. The deposit characteristics are consistent with rapid sedimentation from a low-particle-concentration, turbulent flow onto an aggrading bed. We infer two potential mechanisms for generating these density currents: (1) explosive magma-water interaction involving lithic debris and relatively unfragmented melt; and (2) collapse of oversteepened upper cone slopes due to rapid accumulation of spatter from voluminous Strombolian eruptions.

Do Left- and Right-Handed People Have Similar Iron Deposition in the Basal Ganglia?

PubMed

Wang, Dan; Li, Yue-Hua; Wang, He

2016-01-01

This study aimed to investigate whether right-, left-, or mixed-handed people differ in terms of iron deposition using susceptibility weighted imaging in healthy subjects. A total of 87 people (right-handed, 51 subjects; left-handed, 19 subjects; mixed-handed, 17 subjects) aged 20 to 40 years participated. All underwent magnetic resonance examination, including conventional and susceptibility weighted imaging sequences. Phase images were used to quantify iron deposition in the head of the caudate nucleus and lenticular nucleus. The radian angle value was calculated and compared between the 3 (right-, left-, or mixed-handed) groups. There was no significant difference in the radian angle values between left-, right-, or mixed-handed people for either the right or left side of the caudate nucleus head. However, the amount of iron deposition in the left lenticular nucleus was significantly higher for right-handed than for the left-handed subjects (P < 0.001) and significantly higher for mixed-handed than for left-handed subjects (P = 0.006). In addition, the amount of iron deposition in the right lenticular nucleus was significantly lower for left-handed than for right-handed subjects (P < 0.001). The results revealed no significant differences in iron deposition in the head of the caudate nucleus. However, there was a significant difference in iron deposition in the lenticular nucleus between left- and right-handed subjects and between left- and mixed-handed subjects.

A comparative study on omnidirectional anti-reflection SiO2 nanostructure films coating by glancing angle deposition

NASA Astrophysics Data System (ADS)

Prachachet, R.; Samransuksamer, B.; Horprathum, M.; Eiamchai, P.; Limwichean, S.; Chananonnawathorn, C.; Lertvanithphol, T.; Muthitamongkol, P.; Boonruang, S.; Buranasiri, P.

2018-02-01

Fabricated omnidirectional anti-reflection nanostructure films as a one of the promising alternative solar cell applications have attracted enormous scientific and industrial research benefits to their broadband, effective over a wide range of incident angles, lithography-free and high-throughput process. Recently, the nanostructure SiO2 film was the most inclusive study on anti-reflection with omnidirectional and broadband characteristics. In this work, the three-dimensional silicon dioxide (SiO2) nanostructured thin film with different morphologies including vertical align, slant, spiral and thin films were fabricated by electron beam evaporation with glancing angle deposition (GLAD) on the glass slide and silicon wafer substrate. The morphological of the prepared samples were characterized by field-emission scanning electron microscope (FE-SEM) and high-resolution transmission electron microscope (HRTEM). The transmission, omnidirectional and birefringence property of the nanostructure SiO2 films were investigated by UV-Vis-NIR spectrophotometer and variable angle spectroscopic ellipsometer (VASE). The spectrophotometer measurement was performed at normal incident angle and a full spectral range of 200 - 2000 nm. The angle dependent transmission measurements were investigated by rotating the specimen, with incidence angle defined relative to the surface normal of the prepared samples. This study demonstrates that the obtained SiO2 nanostructure film coated on glass slide substrate exhibits a higher transmission was 93% at normal incident angle. In addition, transmission measurement in visible wavelength and wide incident angles -80 to 80 were increased in comparison with the SiO2 thin film and glass slide substrate due to the transition in the refractive index profile from air to the nanostructure layer that improve the antireflection characteristics. The results clearly showed the enhanced omnidirectional and broadband characteristic of the three dimensional SiO2 nanostructure film coating.

An Experimental Study on Slurry Erosion Resistance of Single and Multilayered Deposits of Ni-WC Produced by Laser-Based Powder Deposition Process

NASA Astrophysics Data System (ADS)

Balu, Prabu; Hamid, Syed; Kovacevic, Radovan

2013-11-01

Single and multilayered deposits containing different mass fractions of tungsten carbide (WC) in nickel (Ni)-matrix (NT-20, NT-60, NT-80) are deposited on a AISI 4140 steel substrate using a laser-based powder deposition process. The transverse cross section of the coupons reveals that the higher the mass fraction of WC in Ni-matrix leads to a more uniform distribution through Ni-matrix. The slurry erosion resistance of the fabricated coupons is tested at three different impingement angles using an abrasive water jet cutting machine, which is quantified based on the erosion rate. The top layer of a multilayered deposit (i.e., NT-60 in a two-layer NT-60 over NT-20 deposit) exhibits better erosion resistance at all three tested impingement angles when compared to a single-layer (NT-60) deposit. A definite increase in the erosion resistance is noted with an addition of nano-size WC particles. The relationship between the different mass fractions of reinforcement (WC) in the deposited composite material (Ni-WC) and their corresponding matrix (Ni) hardness on the erosion rate is studied. The eroded surface is analyzed in the light of a three-dimensional (3-D) profilometer and a scanning electron microscope (SEM). The results show that a volume fraction of approximately 62% of WC with a Ni-matrix hardness of 540 HV resulting in the gouging out of WC from the Ni-matrix by the action of slurry. It is concluded that the slurry erosion resistance of the AISI 4140 steel can be significantly enhanced by introducing single and multilayered deposits of Ni-WC composite material fabricated by the laser-based powder deposition process.

The rotation of ripple pattern and the shape of the collision cascade in ion sputtered thin metal films

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mishra, P.; Ghose, D.

The sputter ripple formation in polycrystalline metal thin films of Al, Co, Cu, and Ag has been studied by 16.7 keV Ar{sup +} and O{sub 2}{sup +} ion bombardment as a function of angle of ion incidence. The experimental results show the existence of a critical angle of ion incidence ({theta}{sub c}) beyond which the ripples of wave vectors perpendicular to the projected ion beam direction appear. Monte Carlo simulation (SRIM) is carried out to calculate the depth, longitudinal and lateral straggling widths of energy deposition as these values are crucial in determining the critical angle {theta}{sub c}. It ismore » found that the radial energy distribution of the damage cascade has the maximum slightly away from the ion path in contradiction to the Gaussian distribution and the distribution is better characterized by an exponential function. The lower values of lateral straggling widths as those extracted from the measured critical angles using the Bradley and Harper theory indicate a highly anisotropic deposited-energy distribution.« less

Validity of in vitro tests on aqueous spray pumps as surrogates for nasal deposition, absorption, and biologic response.

PubMed

Suman, Julie D; Laube, Beth L; Dalby, Richard

2006-01-01

This research investigated the impact of the full range of in vitro spray characterization tests described in the FDA Draft Bioequivalence Guidance on nasal deposition pattern, pharmacokinetics, and biological response to nicotine administered by two aqueous nasal spray pumps in human volunteers. Nicotine was selected as a model drug (even though it is not locally acting) based on its ability to alter cardiac function and available plasma assay. Significant differences in pump performance-including mean volume diameters, spray angle, spray width, and ovality ratios-were observed between the two pumps. There were no significant differences in deposition pattern, or pharmacokinetic or pharmacodynamic response to the nasally administered nicotine. Although there were statistical differences in the in vitro tests between the two pumps, these differences did not result in significant alterations in the site of droplet deposition within the nose, the rate and extent of nicotine absorption, or the physiologic response it induced. These results suggest that current measures of in vitro performance, particularly spray angle and spray pattern (ovality), may not be clinically relevant. Additional research is needed to define what spray pump characteristics are likely to produce differences in deposition pattern and drug response.

Characterization and in vitro biocompatibility study of Ti-Si-N nanocomposite coatings developed by using physical vapor deposition

NASA Astrophysics Data System (ADS)

Trivedi, Pramanshu; gupta, Pallavi; Srivastava, Swati; Jayaganthan, R.; Chandra, Ramesh; Roy, Partha

2014-02-01

Amongst the Ti alloys used as orthopedic implant materials, Ti6Al4V is one of the widely used alloys. Magnetron sputtering was used to deposit nanocomposite coating of Ti-Si-N on the Ti6Al4V substrate at different power and then the coating structure and surface properties were characterized through contact angle measurement, X-ray diffraction (XRD), scanning electron microscopy (SEM), and atomic force microscopy (AFM). In vitro biocompatibility of the coatings was assessed by using mouse bone marrow mesenchymal stem cells (mBMMSC). Antibacterial studies were performed using Escherichia coli (E. coli) microorganisms. The osteogenic differentiation was also carried out in order to get gene expressions. The AFM results confirmed that the coatings deposited at 120 W was smoother as compared to other coatings developed at different power, along with optimum contact angle, also these coatings showed good antibacterial results. The fluorescent and viability results of 120 W sample confirmed their good biocompatibility as compared to the coatings deposited 20, 40, 60, and 100 W power. Hence, the coating deposited at 120 W exhibit desirable microstructural characteristics beneficial for surface modification of orthopedic implants.

Fabrication of nanostructure by physical vapor deposition with glancing angle deposition technique and its applications

NASA Astrophysics Data System (ADS)

Horprathum, M.; Eiamchai, P.; Kaewkhao, J.; Chananonnawathorn, C.; Patthanasettakul, V.; Limwichean, S.; Nuntawong, N.; Chindaudom, P.

2014-09-01

A nanostructural thin film is one of the highly exploiting research areas particularly in applications in sensor, photocatalytic, and solar-cell technologies. In the past two decades, the integration of glancing-angle deposition (GLAD) technique to physical vapor deposition (PVD) process has gained significant attention for well-controlled multidimensional nanomorphologies because of fast, simple, cost-effective, and mass-production capability. The performance and functional properties of the coated thin films generally depend upon their nanostructural compositions, i.e., large aspect ratio, controllable porosity, and shape. Such structural platforms make the fabricated thin films very practical for several realistic applications. We therefore present morphological and nanostructural properties of various deposited materials, which included metals, i.e., silver (Ag), and oxide compounds, i.e., tungsten oxide (WO3), titanium dioxide (TiO2), and indium tin oxide (ITO). Different PVD techniques based on DC magnetron sputtering and electron-beam evaporation, both with the integrated GLAD component, were discussed. We further explore engineered nanostructures which enable controls of optical, electrical, and mechanical properties. These improvements led to several practical applications in surface-enhanced Raman, smart windows, gas sensors, self-cleaning materials and transparent conductive oxides (TCO).

Ultrasound power deposition model for the chest wall.

PubMed

Moros, E G; Fan, X; Straube, W L

1999-10-01

An ultrasound power deposition model for the chest wall was developed based on secondary-source and plane-wave theories. The anatomic model consisted of a muscle-ribs-lung volume, accounted for wave reflection and refraction at muscle-rib and muscle-lung interfaces, and computed power deposition due to the propagation of both reflected and transmitted waves. Lung tissue was assumed to be air-equivalent. The parts of the theory and numerical program dealing with reflection were experimentally evaluated by comparing simulations with acoustic field measurements using several pertinent reflecting materials. Satisfactory agreement was found. A series of simulations were performed to study the influence of angle of incidence of the beam, frequency, and thickness of muscle tissue overlying the ribs on power deposition distributions that may be expected during superficial ultrasound (US) hyperthermia of chest wall recurrences. Both reflection at major interfaces and attenuation in bone were the determining factors affecting power deposition, the dominance of one vs. the other depending on the angle of incidence of the beam. Sufficient energy is reflected by these interfaces to suggest that improvements in thermal doses to overlying tissues are possible with adequate manipulation of the sound field (advances in ultrasonic heating devices) and prospective treatment planning.

(abstract) Optical Scattering and Surface Microroughness of Ion Beam Deposited Au and Pt Thin Films

NASA Technical Reports Server (NTRS)

Al-Jumaily, Ghanim A.; Raouf, Nasrat A.; Edlou, Samad M.; Simons, John C.

1994-01-01

Thin films of gold and platinum have been deposited onto superpolished fused silica substrates using thermal evaporation, ion assisted deposition (IAD), and ion assisted sputtering. The influence of ion beam flux, thin film material, and deposition rate on the films microroughness have been investigated. Short range surface microroughness of the films has been examined using scanning tunneling microscopy (STM) and atomic force microscopy (AFM). Long range surface microroughness has been characterized using an angle resolved optical scatterometer. Results indicate that ion beam deposited coatings have improved microstructure over thermally evaporated films.

Wettability of Y2O3: A Relative Analysis of Thermally Oxidized, Reactively Sputtered and Template Assisted Nanostructured Coatings

PubMed Central

Barshilia, Harish C.; Chaudhary, Archana; Kumar, Praveen; Manikandanath, Natarajan T.

2012-01-01

The wettability of reactively sputtered Y2O3, thermally oxidized Y-Y2O3 and Cd-CdO template assisted Y2O3 coatings has been studied. The wettability of as-deposited Y2O3 coatings was determined by contact angle measurements. The water contact angles for reactively sputtered, thermally oxidized and template assisted Y2O3 nanostructured coatings were 99°, 117° and 155°, respectively. The average surface roughness values of reactively sputtered, thermally oxidized and template assisted Y2O3 coatings were determined by using atomic force microscopy and the corresponding values were 3, 11 and 180 nm, respectively. The low contact angle of the sputter deposited Y2O3 and thermally oxidized Y-Y2O3 coatings is attributed to a densely packed nano-grain like microstructure without any void space, leading to low surface roughness. A water droplet on such surfaces is mostly in contact with a solid surface relative to a void space, leading to a hydrophobic surface (low contact angle). Surface roughness is a crucial factor for the fabrication of a superhydrophobic surface. For Y2O3 coatings, the surface roughness was improved by depositing a thin film of Y2O3 on the Cd-CdO template (average roughness = 178 nm), which resulted in a contact angle greater than 150°. The work of adhesion of water was very high for the reactively sputtered Y2O3 (54 mJ/m2) and thermally oxidized Y-Y2O3 coatings (43 mJ/m2) compared to the Cd-CdO template assisted Y2O3 coating (7 mJ/m2). PMID:28348296

Pattern Effects of Soil on Photovoltaic Surfaces

DOE PAGES

Burton, Patrick D.; Hendrickson, Alex; Ulibarri, Stephen Seth; ...

2016-06-06

The texture or patterning of soil on PV surfaces may influence light capture at various angles of incidence (AOI). Accumulated soil can be considered a microshading element, which changes with respect to AOI. Laboratory deposition of simulated soil was used to prepare test coupons for simultaneous AOI and soiling loss experiments. A mixed solvent deposition technique was used to consistently deposit patterned test soils onto glass slides. Transmission decreased as soil loading and AOI increased. Dense aggregates significantly decreased transmission. But, highly dispersed particles are less prone to secondary scattering, improving overall light collection. In order to test AOI losses on relevant systems, uniform simulated soil coatings were applied to split reference cells to further examine this effect. Finally, the measured optical transmission and area coverage correlated closely to the observedmore » $$I_{{rm SC}}$$. Angular losses were significant at angles as low as 25°.« less

Optical and infrared properties of glancing angle-deposited nanostructured tungsten films.

PubMed

Ungaro, Craig; Shah, Ankit; Kravchenko, Ivan; Hensley, Dale K; Gray, Stephen K; Gupta, Mool C

2015-02-15

Nanotextured tungsten thin films were obtained on a stainless steel (SS) substrate using the glancing-angle-deposition (GLAD) method. It was found that the optical absorption and thermal emittance of the SS substrate can be controlled by varying the parameters used during deposition. Finite-difference time-domain (FDTD) simulations were used to predict the optical absorption and infrared (IR) reflectance spectra of the fabricated samples, and good agreement was found between simulated and measured data. FDTD simulations were also used to predict the effect of changes in the height and periodicity of the nanotextures. These simulations show that good control over the absorption can be achieved by altering the height and periodicity of the nanostructure. These nanostructures were shown to be temperature stable up to 500°C with the addition of a protective HfO2 layer. Applications for this structure are explored, including a promising application for solar thermal energy systems.

Growth of magnesium diboride thin films on boron buffered Si and silicon-on-insulator substrates by hybrid physical chemical vapor deposition

NASA Astrophysics Data System (ADS)

Withanage, Wenura K.; Penmatsa, Sashank V.; Acharya, Narendra; Melbourne, Thomas; Cunnane, D.; Karasik, B. S.; Xi, X. X.

2018-07-01

We report on the growth of high quality MgB2 thin films on silicon and silicon-on-insulator substrates by hybrid physical chemical vapor deposition. A boron buffer layer was deposited on all sides of the Si substrate to prevent the reaction of Mg vapor and Si. Ar ion milling at a low angle of 1° was used to reduce the roughness of the boron buffer layer before the MgB2 growth. An Ar ion milling at low angle of 1° was also applied to the MgB2 surface to reduce its roughness. The resultant MgB2 films showed excellent superconducting properties and a smooth surface. The process produces thin MgB2 films suitable for waveguide-based superconducting hot electron bolometers and other MgB2-based electronic devices.

Preparation of hydrophobic coatings

DOEpatents

Branson, Eric D [Albuquerque, NM; Shah, Pratik B [Albuquerque, NM; Singh, Seema [Rio Rancho, NM; Brinker, C Jeffrey [Albuquerque, NM

2009-02-03

A method for preparing a hydrophobic coating by preparing a precursor sol comprising a metal alkoxide, a solvent, a basic catalyst, a fluoroalkyl compound and water, depositing the precursor sol as a film onto a surface, such as a substrate or a pipe, heating, the film and exposing the film to a hydrophobic silane compound to form a hydrophobic coating with a contact angle greater than approximately 150.degree.. The contact angle of the film can be controlled by exposure to ultraviolet radiation to reduce the contact angle and subsequent exposure to a hydrophobic silane compound to increase the contact angle.

3D architecture of cyclic-step and antidune deposits in glacigenic subaqueous fan and delta settings: Integrating outcrop and ground-penetrating radar data

NASA Astrophysics Data System (ADS)

Lang, Jörg; Sievers, Julian; Loewer, Markus; Igel, Jan; Winsemann, Jutta

2017-12-01

Bedforms related to supercritical flows are increasingly recognised as important constituents of many depositional environments, but outcrop studies are commonly hampered by long bedform wavelengths and complex three-dimensional geometries. We combined outcrop-based facies analysis with ground-penetrating radar (GPR) surveys to analyse the 3D facies architecture of subaqueous ice-contact fan and glacifluvial delta deposits. The studied sedimentary systems were deposited at the margins of the Middle Pleistocene Scandinavian ice sheets in Northern Germany. Glacifluvial Gilbert-type deltas are characterised by steeply dipping foreset beds, comprising cyclic-step deposits, which alternate with antidune deposits. Deposits of cyclic steps consist of lenticular scours infilled by backset cross-stratified pebbly sand and gravel. The GPR sections show that the scour fills form trains along the delta foresets, which can locally be traced for up to 15 m. Perpendicular and oblique to palaeoflow direction, these deposits appear as troughs with concentric or low-angle cross-stratified infills. Downflow transitions from scour fills into sheet-like low-angle cross-stratified or sinusoidally stratified pebbly sand, deposited by antidunes, are common. Cyclic steps and antidunes were deposited by sustained and surge-type supercritical density flows, which were related to hyperpycnal flows, triggered by major meltwater discharge or slope-failure events. Subaqueous ice-contact fan deposits include deposits of progradational scour fills, isolated hydraulic jumps, antidunes and (humpback) dunes. The gravel-rich fan succession consists of vertical stacks of laterally amalgamated pseudo-sheets, indicating deposition by pulses of waning supercritical flows under high aggradation rates. The GPR sections reveal the large-scale architecture of the sand-rich fan succession, which is characterised by lobe elements with basal erosional surfaces associated with scours filled with backsets related to hydraulic jumps, passing upwards and downflow into deposits of antidunes and (humpback) dunes. The recurrent facies architecture of the lobe elements and their prograding and retrograding stacking pattern are interpreted as related to autogenic flow morphodynamics.

Visualization of the equilibrium position of colloidal particles at fluid-water interfaces by deposition of nanoparticles

NASA Astrophysics Data System (ADS)

Sabapathy, Manigandan; Kollabattula, Viswas; Basavaraj, Madivala G.; Mani, Ethayaraja

2015-08-01

We present a general yet simple method to measure the contact angle of colloidal particles at fluid-water interfaces. In this method, the particles are spread at the required fluid-water interface as a monolayer. In the water phase a chemical reaction involving reduction of a metal salt such as aurochloric acid is initiated. The metal grows as a thin film or islands of nanoparticles on the particle surface exposed to the water side of the interface. Analyzing the images of particles by high resolution scanning microscopy (HRSEM), we trace the three phase contact line up to which deposition of the metal film occurs. From geometrical relations, the three phase contact angle is then calculated. We report the measurements of the contact angle of silica and polystyrene (PS) particles at different interfaces such as air-water, decane-water and octanol-water. We have also applied this method to measure the contact angle of surfactant treated polystyrene particles at the air-water interface, and we find a non-monotonic change of the contact angle with the concentration of the surfactant. Our results are compared with the well-known gel trapping technique and we find good comparison with previous measurements.We present a general yet simple method to measure the contact angle of colloidal particles at fluid-water interfaces. In this method, the particles are spread at the required fluid-water interface as a monolayer. In the water phase a chemical reaction involving reduction of a metal salt such as aurochloric acid is initiated. The metal grows as a thin film or islands of nanoparticles on the particle surface exposed to the water side of the interface. Analyzing the images of particles by high resolution scanning microscopy (HRSEM), we trace the three phase contact line up to which deposition of the metal film occurs. From geometrical relations, the three phase contact angle is then calculated. We report the measurements of the contact angle of silica and polystyrene (PS) particles at different interfaces such as air-water, decane-water and octanol-water. We have also applied this method to measure the contact angle of surfactant treated polystyrene particles at the air-water interface, and we find a non-monotonic change of the contact angle with the concentration of the surfactant. Our results are compared with the well-known gel trapping technique and we find good comparison with previous measurements. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr03369a

Influence of internal pore architecture on biological and mechanical properties of three-dimensional fiber deposited scaffolds for bone regeneration.

PubMed

Ostrowska, Barbara; Di Luca, Andrea; Szlazak, Karol; Moroni, Lorenzo; Swieszkowski, Wojciech

2016-04-01

Fused deposition modeling has been used to fabricate three-dimensional (3D) scaffolds for tissue engineering applications, because it allows to tailor their pore network. Despite the proven flexibility in doing so, a limited amount of studies have been performed to evaluate whether specific pore shapes have an influence on cell activity and tissue formation. Our study aimed at investigating the influence of internal pore architecture on the biological and mechanical properties of 3D scaffolds seeded with mesenchymal stromal cells. Polycaprolactone scaffolds with six different geometries were fabricated. The 3D samples were manufactured with different lay-down pattern of the fibers by varying the layer deposition angle from 0°/15°/30°, to 0°/30°/60°, 0°/45°/90°, 0°/60°/120°, 0°/75°/150°, and 0°/90°/180°. The scaffolds were investigated by scanning electron microscopy and micro computed tomographical analysis and displayed a fully interconnected pore network. Cell proliferation and differentiation toward the osteogenic lineage were evaluated by DNA, alkaline phosphatase activity, and polymerase chain reaction. The obtained scaffolds had structures with open porosity (50%-60%) and interconnected pores ranging from 380 to 400 µm. Changing the angle deposition affected significantly the mechanical properties of the scaffolds. With increasing the angle deposition between successive layers, the elastic modulus increased as well. Cellular studies also showed influence of the internal architecture on cell adhesion and proliferation within the 3D construct, yet limited influence on cell differentiation was observed. © 2016 Wiley Periodicals, Inc.

Long-term stabilization of sprayed zinc oxide thin film transistors by hexafluoropropylene oxide self assembled monolayers

NASA Astrophysics Data System (ADS)

Ortel, Marlis; Kalinovich, Nataliya; Röschenthaler, Gerd-Volker; Wagner, Veit

2013-09-01

Surface functionalization of solution processed zinc oxide layers was studied in transistors with bottom-gate bottom-contact configuration aiming at suppression of trapping processes to increase device stability. Saturation of electrically active surface sites and formation of a moisture barrier to decrease the impact of humid atmosphere was successfully shown by binding hexafluoropropylene oxide (HFPO) on the metal oxide semiconductor. Deep trap level related electrical parameters, i.e., stability, hysteresis, and on-set voltage, improved rapidly within 60 s of exposure which was attributed to occupation of sites characterized by low adsorption energies, e.g., at edges. In contrast, shallow trap level related parameters, i.e., mobility, showed a much slower process of improvement. Identical behavior was determined for the contact angle. A physical model is presented by applying first order reaction kinetics equation to Young's law and multiple trapping and release model which relates the dependence of the contact angle and the mobility to the hexafluoropropylene oxide deposition time. Consistent time constants of τ = ≪1 min, 2 min, and 250 min were extracted for mobility and contact angle which implies a direct dependence on the surface coverage. Mobility decreased at short deposition times, recovered at medium deposition times and improved strongly by 2.4 cm2 V-1 s-1 for long deposition times of 1400 min. A microscopic model of these phenomena is given with interpretation of the different time constants found in the experiment.

Deciphering sub-micron ice particles on Enceladus surface

NASA Astrophysics Data System (ADS)

Scipioni, F.; Schenk, P.; Tosi, F.; D'Aversa, E.; Clark, R.; Combe, J.-Ph.; Ore, C. M. Dalle

2017-07-01

The surface of Saturn's moon Enceladus is composed primarily by pure water ice. The Cassini spacecraft has observed present-day geologic activity at the moon's South Polar Region, related with the formation and feeding of Saturn's E-ring. Plumes of micron-sized particles, composed of water ice and other non-ice contaminants (e.g., CO2, NH3, CH4), erupt from four terrain's fractures named Tiger Stripes. Some of this material falls back on Enceladus' surface to form deposits that extend to the North at ∼40°W and ∼220°W, with the highest concentration found at the South Pole. In this work we analyzed VIMS-IR data to identify plumes deposits across Enceladus' surface through the variation in band depth of the main water ice spectral features. To characterize the global variation of water ice band depths across Enceladus, the entire surface was sampled with an angular resolution of 1° in both latitude and longitude, and for each angular bin we averaged the value of all spectral indices as retrieved by VIMS. The position of the plumes' deposits predicted by theoretical models display a good match with water ice band depths' maps on the trailing hemisphere, whereas they diverge significantly on the leading side. Space weathering processes acting on Enceladus' surface ionize and break up water ice molecules, resulting in the formation of particles smaller than one micron. We also mapped the spectral indices for sub-micron particles and we compared the results with the plumes deposits models. Again, a satisfactory match is observed on the trailing hemisphere only. Finally, we investigated the variation of the depth of the water ice absorption bands as a function of the phase angle. In the visible range, some terrains surrounding the Tiger Stripes show a decrease in albedo when the phase angle is smaller than 10°. This unusual effect cannot be confirmed by near infrared data, since observations with a phase angle lower than 10° are not available. For phase angle values greater than 10°, the depth of the water ice features remains quite constant within a broad range of phase angle values.

Enhanced Chemisorption of Cu(hfac)2 on Parylene Surface by N2 Plasma Treatment

NASA Astrophysics Data System (ADS)

Pimanpang, S.; Wang, P.-I.; Ye, D.-X.; Juneja, J. S.; Wang, G.-C.; Lu, T.-M.

2006-03-01

The metallization of polymers has been intensively studied due to its wide industrial applications. We report a study of interfacial interaction of metalorganic Cu(hfac)2 with the Parylene surface. Parylene is a low k dielectric polymer prepared by a chemical vapor deposition technique. The as-deposited Parylene surface is shown to be hydrophobic with a measured water droplet contact angle ˜72 . However, after the N2 plasma treatment, the water droplet contact angle decreases to ˜40 due to the formation of oxygen and nitrogen functional groups on the surface, as observed by x-ray photoelectron spectroscopy (XPS). These functional groups improve Cu(hfac)2 chemisorption on the plasma treated Parylene surface. Further studies by XPS show that chemisorption of Cu(hfac)2 is self-limiting up to 20 sec of Cu(hfac)2 precursor exposure time. The enhancement of chemisorption of metalorganic precursors on the polymer surface is an important step for chemical vapor deposition or atomic layer deposition of metal. ^a Supported by Thai govt. fellowship (SP) and SRC (JSJ).

Microstructure evolution of Al-doped zinc oxide films prepared by in-line reactive mid-frequency magnetron sputtering

NASA Astrophysics Data System (ADS)

Hong, R. J.; Jiang, X.

2006-07-01

Aluminium-doped zinc oxide (ZnO:Al or AZO) thin films were deposited on glass substrates by reactive mid-frequency (MF) magnetron sputtering from Zn/Al metallic targets. Strong (002) preferred orientation was detected by X-ray diffraction (XRD). It was observed by plan-view transmission electron microscopy (TEM) that an AZO film deposited at low substrate temperature was composed of irregular large grains; but the film prepared at high temperature was composed of moderate sized grains with a regular shape. A secondary phase of ZnO2 was also observed for the film deposited at low substrate temperature. The cross-sectional TEM study of the AZO film showed that prior to the well-aligned columnar growth an initial interfacial zone with nano crystallites were formed. The nano crystallites formed initially with a large tilt angle normal to the substrate surface and during the growth of the transition zone, the tilt angle decreased until it vanished. The evolution of the film structure is discussed in terms of evolutionary selection model and the dynamic deposition process.

High Power Optical Coatings by Atomic Layer Deposition and Signatures of Laser-Induced Damage

DTIC Science & Technology

2012-08-28

diffraction angle 0 into crystal lattice spacing d by the Bragg condition, mX = 2d sin 0. Here X is the x - ray wavelength... angle x - ray diffraction (GAXRD) measurements, which were made at a fixed shallow incidence angle of 0.5°. Detector scans were done to measure the...was finished with 200 hafnia cycles m the fmal half period rather than 400. Crystallinity was measured by x - ray diffraction (XRD) with

Electric-regulated enhanced in-plane uniaxial anisotropy in FeGa/PMN-PT composite using oblique pulsed laser deposition

NASA Astrophysics Data System (ADS)

Zhang, Yi; Huang, Chaojuan; Turghun, Mutellip; Duan, Zhihua; Wang, Feifei; Shi, Wangzhou

2018-04-01

The FeGa film with in-plane uniaxial magnetic anisotropy was fabricated onto different oriented single-crystal lead magnesium niobate-lead titanate using oblique pulsed laser deposition. An enhanced in-plane uniaxial magnetic anisotropy field of FeGa film can be adjusted from 18 Oe to 275 Oe by tuning the oblique angle and polarizing voltage. The competitive relationship of shape anisotropy and strain anisotropy has been discussed, which was induced by oblique angle and polarizing voltage, respectively. The (100)-oriented and (110)-oriented PMN-PT show completely different characters on voltage-dependent magnetic properties, which could be attributed to various anisotropy directions depended on different strain directions.

The effect of Si nano-columns in 2-D and 3-D on cellular behaviour: nanotopography-induced CaP deposition from differentiating mesenchymal stem cells.

PubMed

Guvendik, S; Trabzon, L; Ramazanoglu, M

2011-10-01

Si nano-columns were deposited in 2-D and 3-D in the form of well-defined geometries by physical vapor deposition. The films were grown by e-beam evaporation with an angle between source and substrate. The Si nano-columns were deposited in the shape of spiral with two different incoming atomic flux angle so that the manipulation of nano-columns in 3-D (out-of-plane) was obtained. The Si nano-columns were also grown as vertical stick with square, triangle and linear cross sections in 2D (in-plane). Rat bone marrow mesenchymal stem cells (MSCs) were cultured on these different Si nanosurfaces. MTS assay was carried out to determine the cell proliferation and viability based on different nanotopographies. For the evaluation of cell distribution and morphology, a SEM (Scanning Electron Microscopy) analysis was performed. Any CaP deposition on Si nanosurfaces was observed using energy dispersive X-Ray spectroscopy in SEM (SEM-EDX). After 4 days of culture, there was a higher value of cell proliferation on square columns and spiral Si nano-columns grown with 85 degrees of incoming atomic flux. The cell attachment and spreading was also affected by the geometry of Si nano-columns. While there were still cells showing round/spherical morphology with minimal spreading on conventional Si surfaces, most of the cells cultured on different Si nanotopographies attached on the surface and displayed flattened morphology, especially on the square columns surface. Moreover, CaP deposition was discovered on square columns and spiral films with 85 degrees substrate angle. So, it can be concluded that there is a clear correlation between cell responses and nano-sized geometry on Si surface and it is possible to induce cellular differentiation and CaP formation in certain geometrical constraints.

The Lavrion Pb-Zn-Fe-Cu-Ag detachment-related district (Attica, Greece): Structural control on hydrothermal flow and element transfer-deposition

NASA Astrophysics Data System (ADS)

Scheffer, Christophe; Tarantola, Alexandre; Vanderhaeghe, Olivier; Voudouris, Panagiotis; Rigaudier, Thomas; Photiades, Adonis; Morin, Denis; Alloucherie, Alison

2017-10-01

The impact of lithological heterogeneities on deformation, fluid flow and ore deposition is discussed based on the example of the Lavrion low-angle detachment partly accommodating gravitational collapse of the Hellenides orogenic belt in Greece. The Lavrion peninsula is characterised by a multiphase Pb-Zn-Fe-Cu-Ag ore system with a probable pre-concentration before subduction followed by progressive remobilisation and deposition coeval with the development of a low-angle ductile to brittle shear zone. The mylonitic marble below the detachment shear zone is composed of white layers of pure marble alternating with blue layers containing impurities (SiO2, Al2O3, carbonaceous material). Ductile mylonitic deformation is more pervasive in the less competent impure blue marble. We propose that localised deformation in the impure marble is associated with fluid circulation and dolomitisation, which in turn causes an increase in competence of these layers. Mineralised cataclastic zones, crosscutting the mylonitic fabric, are preferentially localised in the more competent dolomitic layers. Oxygen and carbon isotopic signatures of marble invaded by carbonate replacement deposits during ductile to ductile-brittle deformation are consistent with decarbonation coeval with the invasion of magmatic fluids. Mineralised cataclastic zones reflecting brittle deformation evolve from low 13C to low 18O signatures, interpreted as local interaction with carbonaceous material that trends toward the contribution of a surface-derived fluid. These features indicate that the Lavrion area records a complex deposition history influenced by the evolution of fluid reservoirs induced by the thermal and mechanical evolution of the marble nappe stack. Ore remobilisation and deposition associated with the activity of the low-angle detachment is (i) firstly related to the intrusion of the Plaka granodiorite leading to porphyry-type and carbonate replacement mineralisation during ductile-brittle deformation and (ii) then marked by progressive penetration of surface-derived fluids guided by strain localisation in the more competent levels leading to epithermal mineralisation associated with brittle deformation.

Granular flow behavior at sharp changes in slope

NASA Astrophysics Data System (ADS)

Crosta, Giovanni; De Blasio, Fabio; Locatelli, Michele

2015-04-01

This study extends some recent experiments and analyses performed by the authors to examine the behavior of granular flows along path characterised by sharp changes in slope. In particular, various series of experiments along a bi-linear broken slope (an inclined initial sector followed by a horizontal one) have been completed using a uniform (Hostun, 0.32 mm) sand and a uniform fine gravel (2 mm grains). 60 new have been performed by releasing different volumes (1.5, 2.1 and 5.1 L) on surfaces characterized by different slope angles (35-60°), type of materials (wood and plexiglass), with or without an erodible layer (sand), or in presence of a shallow water pond (0.5 cm). These geometrical features are typical of many large rock and snow avalanches, rock falls and of chalk flows. The latter are usually typical of coastal cliffs where a shallow water environment is typical. The evolution of the flow has been monitored through a laser profilometer at 120 Hz sampling frequency and high speed camera, and in this way it has been possible to follow the evolution of the flow and deposition, and to analyse the change in deposition mode at varying the slope angle, the material and the basal friction. This is an extremely interesting development in the study of the evolution of the deposition and of the final morphology typical of such phenomena, and can support the testing of numerical models. Propagation and deposition occur forward or backward accordingly to the slope angle and the basal friction. Forward movement and deposition occur at high slope angles and with low basal friction. The opposite is true for the backward deposition. The internal "layering" within the deposit is also strongly controlled by the combination of such parameters. The time evolution of the flow allowed to determine the velocity of flow and the mode of deposition through the analysis of the change in thickness, position of the front and of the flow tail. Presence of water reduces the runout of the sand on the horizontal sector of the path, whereas the opposite seems true for the gravel. In these cases, as already shown by the authors (Crosta et al., submitted), a partial reflection of the flow occurs and the same holds true when a shallow water reservoir exists. Furthermore, a sort of hydroplaning phenomenon occurs which controls the initial part of the expansion along the subhorizontal sector of the path. Results of the experimental campaign have been compared against those from simple analytical models which assume the energy loss at the slope break and numerical simulations performed by a FEM-ALE (2D and fully 3D) modeling.

Structural controls on Carlin-type gold mineralization in the gold bar district, Eureka County, Nevada

USGS Publications Warehouse

Yigit, O.; Nelson, E.P.; Hitzman, M.W.; Hofstra, A.H.

2003-01-01

The Gold Bar district in the southern Roberts Mountains, 48 km northwest of Eureka, Nevada, contains one main deposit (Gold Bar), five satellite deposits, and other resources. Approximately 0.5 Moz of gold have been recovered from a resource of 1,639,000 oz of gold in Carlin-type gold deposits in lower plate, miogeoclinal carbonate rocks below the Roberts Mountains thrust. Host rocks are unit 2 of the Upper Member of the Devonian Denay Formation and the Bartine Member of the McColley Canyon Formation. Spatial and temporal relations between structures and gold mineralization indicate that both pre-Tertiary and Tertiary structures were important controls on gold mineralization. Gold mineralization occurs primarily along high-angle Tertiary normal faults, some of which are reactivated reverse faults of Paleozoic or Mesozoic age. Most deposits are localized at the intersection of northwest- and northeast-striking faults. Alteration includes decalcification, and to a lesser extent, silicification along high-angle faults. Jasperoid (pervasive silicification), which formed along most faults and in some strata-bound zones, accounts for a small portion of the ore in every deposit. In the Gold Canyon deposit, a high-grade jasperoid pipe formed along a Tertiary normal fault which was localized along a zone of overturned fault-propagation folds and thrust faults of Paleozoic or Mesozoic age.

Comparison of treatment costs in inadequately controlled type 2 diabetes in Germany based on the APOLLO trial with insulin glargine.

PubMed

Bretzel, Reinhard G; Dippel, Franz-Werner; Linn, Thomas; Neilson, Aileen Rae

2009-06-01

A cost analysis of once-daily insulin glargine versus three-times daily insulin lispro in combination with oral antidiabetic drugs (OADs) for insulin-naive type 2 diabetes patients in Germany based on the APOLLO trial (A Parallel design comparing an Oral antidiabetic drug combination therapy with either Lantus once daily or Lispro at mealtime in type 2 diabetes patients failing Oral treatment). Annual direct treatment costs were estimated from the perspective of the German statutory health insurance (SHI). Costs accounted for included insulin medication, disposable pens and consumable items (needles, blood glucose test strips and lancets). Sensitivity analyses (on resource use and unit costs) were performed to reflect current German practice. Average treatment costs per patient per year in the base case were 1,073 euro for glargine and 1,794 euro for lispro. Insulin costs represented 65% vs. 37% of total costs respectively. Acquisition costs of glargine were offset by the lower costs of consumable items (380 euro vs. 1,139 euro). Sensitivity analyses confirmed the robustness of the results in favour of glargine. All scenarios yielded cost savings in total treatment costs ranging from 84 euro to 727 euro. Combination therapy of once-daily insulin glargine versus three-times daily insulin lispro both with OADs, in the management of insulin-dependent type 2 diabetes offers the potential for substantial cost savings from the German SHI perspective.

Insulin therapy at onset of type 2 diabetes mellitus--a new concept.

PubMed

Sahay, B K

2011-04-01

In this study, insulin therapy was initiated at onset of disease in patients whose fasting blood glucose was more than 250 mg/dl. All enrolled subjects were treated with human premixed insulin (30/70) administered subcutaneously twice daily before breakfast and before dinner. A total of 113 subjects entered the study fulfilling the inclusion criteria. Good glycaemic control was achieved in a few days. The dosage requirement of insulin came down gradually after control was achieved as manifest by hypoglycaemia--leading to withdrawal of insulin. Some of them were managed with diet and exercise alone. Others required small doses of oral antidiabetic agents (OAD). There were no cases of secondary failure to OADs. Ten cases are on average duration of follow-up of 10 years. Two cases are under good control with diet and exercise alone, seven on treatment with oral hypoglycemic agents and one of them requiring insulin to maintain HbAlc below 7%. Thus insulin therapy at onset provides an opportunity to correct all the underlying pathogenic mechanisms, i.e., glucotoxicity, lipotoxicity and prevents beta cell apoptosis and suppresses inflammation, leading to beta cell protection. Such timely intervention provides long term benefits, laying the foundation for the concept of beta cell preservation rather that only replacing beta cell function. Hence we propose that all patients with type 2 diabetes should be offered insulin therapy at the onset of their diabetes for a period of 2-4 weeks.

Saxagliptin, a potent, selective inhibitor of DPP-4, does not alter the pharmacokinetics of three oral antidiabetic drugs (metformin, glyburide or pioglitazone) in healthy subjects.

PubMed

Patel, C G; Kornhauser, D; Vachharajani, N; Komoroski, B; Brenner, E; Handschuh del Corral, M; Li, L; Boulton, D W

2011-07-01

To evaluate the pharmacokinetic interactions of the potent, selective, dipeptidyl peptidase-4 inhibitor, saxagliptin, in combination with metformin, glyburide or pioglitazone. To assess the effect of co-administration of saxagliptin with oral antidiabetic drugs (OADs) on the pharmacokinetics and tolerability of saxagliptin, 5-hydroxy saxagliptin, metformin, glyburide, pioglitazone and hydroxy-pioglitazone, analyses of variance were performed on maximum (peak) plasma drug concentration (C(max)), area under the plasma concentration-time curve from time zero to infinity (AUC(∞)) [saxagliptin + metformin (study 1) and saxagliptin + glyburide (study 2)] and area under the concentration-time curve from time 0 to time t (AUC) [saxagliptin + pioglitazone (study 3)] for each analyte in the respective studies. Studies 1 and 2 were open-label, randomized, three-period, three-treatment, crossover studies, and study 3 was an open-label, non-randomized, sequential study in healthy subjects. Co-administration of saxagliptin with metformin, glyburide or pioglitazone did not result in clinically meaningful alterations in the pharmacokinetics of saxagliptin or its metabolite, 5-hydroxy saxagliptin. Following co-administration of saxagliptin, there were no clinically meaningful alterations in the pharmacokinetics of metformin, glyburide, pioglitazone or hydroxy-pioglitazone. Saxagliptin was generally safe and well tolerated when administered alone or in combination with metformin, glyburide or pioglitazone. Saxagliptin can be co-administered with metformin, glyburide or pioglitazone without a need for dose adjustment of either saxagliptin or these OADs. © 2011 Blackwell Publishing Ltd.

Investigating Effects of Fused-Deposition Modeling (FDM) Processing Parameters on Flexural Properties of ULTEM 9085 using Designed Experiment.

PubMed

Gebisa, Aboma Wagari; Lemu, Hirpa G

2018-03-27

Fused-deposition modeling (FDM), one of the additive manufacturing (AM) technologies, is an advanced digital manufacturing technique that produces parts by heating, extruding and depositing filaments of thermoplastic polymers. The properties of FDM-produced parts apparently depend on the processing parameters. These processing parameters have conflicting advantages that need to be investigated. This article focuses on an investigation into the effect of these parameters on the flexural properties of FDM-produced parts. The investigation is carried out on high-performance ULTEM 9085 material, as this material is relatively new and has potential application in the aerospace, military and automotive industries. Five parameters: air gap, raster width, raster angle, contour number, and contour width, with a full factorial design of the experiment, are considered for the investigation. From the investigation, it is revealed that raster angle and raster width have the greatest effect on the flexural properties of the material. The optimal levels of the process parameters achieved are: air gap of 0.000 mm, raster width of 0.7814 mm, raster angle of 0°, contour number of 5, and contour width of 0.7814 mm, leading to a flexural strength of 127 MPa, a flexural modulus of 2400 MPa, and 0.081 flexural strain.

Hydrophobic Surface Modification of Silk Fabric Using Plasma-Polymerized Hmdso

NASA Astrophysics Data System (ADS)

Rani, K. Vinisha; Chandwani, Nisha; Kikani, Purvi; Nema, S. K.; Sarma, Arun Kumar; Sarma, Bornali

In this work, we study the hydrophobic properties of silk fabrics by deposition of plasma-polymerized (pp) hexamethyldisiloxane (HMDSO) using low-pressure plasma-enhanced chemical vapor deposition. Recently, hydrophobic properties are under active research in textile industry. The effects of coating time and power on the HMDSO-coated silk fabrics are investigated. Water contact angle of pp-HMDSO-coated silk fabric surface is measured as a function of power and coating time. Fabric surface shows an enhancement in hydrophobicity after coating. Attenuated total reflectance-Fourier transform infrared spectroscopy reveals the surface chemistry, and scanning electron microscopy shows the surface morphology of the uncoated and HMDSO-coated fabrics, respectively. In the case of uncoated fabric, water droplet absorbs swiftly, whereas in the case of HMDSO-coated fabric, water droplet remains on the fabric surface with a maximum contact angle of 140∘. The HMDSO-deposited silk surface is found to be durable after detergent washing. Common stains such as ink, tea, milk, turmeric and orange juice are tested on the surface of both fabrics. In HMDSO-coated fabrics, all the stains are bedded like ball droplet. In order to study the self-cleaning property, the fabric is tilted to 45∘ angle; stain droplets easily roll off from the fabric.

Plume mass flow and optical damage distributions for an MMH/N2O4 RCS thruster. [exhaust plume contamination of spacecraft components

NASA Technical Reports Server (NTRS)

Spisz, E. W.; Bowman, R. L.; Jack, J. R.

1973-01-01

The data obtained from two recent experiments conducted in a continuing series of experiments at the Lewis Research Center into the contamination characteristics of a 5-pound thrust MMH/N2O4 engine are presented. The primary objectives of these experiments were to establish the angular distribution of condensible exhaust products within the plume and the corresponding optical damage angular distribution of transmitting optical elements attributable to this contaminant. The plume mass flow distribution was measured by five quartz crystal microbalances (QCM's) located at the engine axis evaluation. The fifth QCM was located above the engine and 15 deg behind the nozzle exit plane. The optical damage was determined by ex-situ transmittance measurements for the wavelength range from 0.2 to 0.6 microns on 2.54 cm diameter fused silica discs also located at engine centerline elevation. Both the mass deposition and optical damage angular distributions followed the expected trend of decreasing deposition and damage as the angle between sensor or sample and the nozzle axis increased. A simple plume gas flow equation predicted the deposition distribution reasonably well for angles of up to 55 degrees. The optical damage measurements also indicated significant effects at large angles.

Investigating Effects of Fused-Deposition Modeling (FDM) Processing Parameters on Flexural Properties of ULTEM 9085 using Designed Experiment

PubMed Central

Gebisa, Aboma Wagari

2018-01-01

Fused-deposition modeling (FDM), one of the additive manufacturing (AM) technologies, is an advanced digital manufacturing technique that produces parts by heating, extruding and depositing filaments of thermoplastic polymers. The properties of FDM-produced parts apparently depend on the processing parameters. These processing parameters have conflicting advantages that need to be investigated. This article focuses on an investigation into the effect of these parameters on the flexural properties of FDM-produced parts. The investigation is carried out on high-performance ULTEM 9085 material, as this material is relatively new and has potential application in the aerospace, military and automotive industries. Five parameters: air gap, raster width, raster angle, contour number, and contour width, with a full factorial design of the experiment, are considered for the investigation. From the investigation, it is revealed that raster angle and raster width have the greatest effect on the flexural properties of the material. The optimal levels of the process parameters achieved are: air gap of 0.000 mm, raster width of 0.7814 mm, raster angle of 0°, contour number of 5, and contour width of 0.7814 mm, leading to a flexural strength of 127 MPa, a flexural modulus of 2400 MPa, and 0.081 flexural strain. PMID:29584674

Transforming a Simple Commercial Glue into Highly Robust Superhydrophobic Surfaces via Aerosol-Assisted Chemical Vapor Deposition.

PubMed

Zhuang, Aoyun; Liao, Ruijin; Lu, Yao; Dixon, Sebastian C; Jiamprasertboon, Arreerat; Chen, Faze; Sathasivam, Sanjayan; Parkin, Ivan P; Carmalt, Claire J

2017-12-06

Robust superhydrophobic surfaces were synthesized as composites of the widely commercially available adhesives epoxy resin (EP) and polydimethylsiloxane (PDMS). The EP layer provided a strongly adhered micro/nanoscale structure on the substrates, while the PDMS was used as a post-treatment to lower the surface energy. In this study, the depositions of EP films were taken at a range of temperatures, deposition times, and substrates via aerosol-assisted chemical vapor deposition (AACVD). A novel dynamic deposition temperature approach was developed to create multiple-layered periodic micro/nanostructures that significantly improved the surface mechanical durability. Water droplet contact angles (CA) of 160° were observed with droplet sliding angles (SA) frequently <1°. A rigorous sandpaper abrasion test demonstrated retention of superhydrophobic properties and superior robustness therein, while wear, anticorrosion (pH = 1-14, 72 h), and UV testing (365 nm, 3.7 mW/cm 2 , 120 h) were carried out to exhibit the environmental stability of the films. Self-cleaning behavior was demonstrated in clearing the surfaces of various contaminating powders and aqueous dyes. This facile and flexible method for fabricating highly durable superhydrophobic polymer films points to a promising future for AACVD in their scalable and low-cost production.

Effects of fabric anisotropy on elastic shear modulus of granular soils

NASA Astrophysics Data System (ADS)

Li, Bo; Zeng, Xiangwu

2014-06-01

The fabric anisotropy of a granular soil deposit can strongly influence its engineering properties and behavior. This paper presents the results of a novel experimental study designed to examine the effects of fabric anisotropy on smallstrain stiffness and its evolution with loading on the elastic shear modulus of granular materials under a K 0 condition. Two primary categories of fabric anisotropy, i.e., deposition-induced and particle shape-induced, are investigated. Toyoura sand deposits with relative densities of 40% and 80% were prepared using deposition angles oriented at 0° and 90°. Piezoelectric transducers were used to obtain the elastic shear modulus in the vertical and horizontal directions ( G vh and G hh). The measurements indicate distinct differences in the values of G with respect to the different deposition angles. Particle shapeinduced fabric anisotropy was examined using four selected sands. It was concluded that sphericity is a controlling factor dominating the small-strain stiffness of granular materials. The degree of fabric anisotropy proves to be a good indicatorin the characterization of stress-induced fabric evolution during loading and unloading stress cycles. The experimental data were used to calibrate an existing micromechanical model, which was able to represent the behavior of the granular material and the degree of fabric anisotropy reasonably well.

Pulsed Laser Deposited Ferromagnetic Chromium Dioxide thin Films for Applications in Spintronics

NASA Astrophysics Data System (ADS)

Dwivedi, S.; Jadhav, J.; Sharma, H.; Biswas, S.

Stable rutile type tetragonal chromium dioxide (CrO2) thin films have been deposited on lattice-matched layers of TiO2 by KrF excimer laser based pulsed laser deposition (PLD) technique using Cr2O3 target. The TiO2 seed layer was deposited on oxidized Si substrates by the same PLD process followed by annealing at 1100 °C for 4 h. The lattice-matched interfacial layer is required for the stabilization of Cr (IV) phase in CrO2, since CrO2 behaves as a metastable compound under ambient conditions and readily converts into its stable phase of Cr (III) oxide, Cr2O3. Analyses with X-ray diffraction (XRD), Glancing-angle XRD (GIXRD), Raman spectroscopy and grazing-angle Fourier transform infra-red (FTIR) spectroscopy confirm the presence of tetragonal CrO2 phase in the as-deposited films. Microstructure and surface morphology in the films were studied with field emission scanning electron microscope (FESEM) and atomic force microscope (AFM). Electrical and magnetic characterizations of the films were performed at room temperature. Such type of stable half-metallic CrO2 thin films with low field magnetoresistive switching behaviour are in demand for applications as diverse as spin-FETs, magnetic sensors, and magneto-optical devices.

The flip-over effect in pulsed laser deposition: Is it relevant at high background gas pressures?

NASA Astrophysics Data System (ADS)

Ojeda-G-P, Alejandro; Schneider, Christof W.; Döbeli, Max; Lippert, Thomas; Wokaun, Alexander

2015-12-01

In pulsed laser deposition the use of a rectangular or elliptical beam spot with a non 1:1 aspect ratio leads to the so called flip-over effect. Here, the longest dimension of the laser spot results in the shortest direction of plasma plume expansion. This effect has been mainly reported for vacuum depositions of single element targets and is particularly noticeable when the aspect ratio of the beam spot is large. We investigate the flip-over effect in vacuum and at three relevant background-gas pressures for pulsed laser deposition using a La0.4Ca0.6MnO3 target by measuring the thickness dependence of the deposited material as a function of angle. The film thicknesses and compositions are determined by Rutherford backscattering and argon is used to reduce the influence of additional chemical reactions in the plasma. The results show the prevalence of the flip-over effect for all pressures except for the highest, i.e. 1 × 10-1 mbar, where the film thickness is constant for all angles. The composition profiles show noticeable compositional variations of up to 30% with respect to the target material depending on the background gas pressure, the angular location, and the laser spot dimensions.

Packing the silica colloidal crystal beads: a facile route to superhydrophobic surfaces.

PubMed

Sun, Cheng; Gu, Zhong-Ze; Xu, Hua

2009-11-03

To mimic the structure of the lotus leaf, we present a facile route to prepare superhydrophobic surfaces by depositing nanoparticle clusters onto a solid surface. These clusters were fabricated via solidification of an emulsion droplet containing a nanoparticle in silicone oil. Thus, the microsized clusters and nanoparticles form dual-scale roughness structures. The surface is modified by fluoroalkylsilane and exhibits superhydrophobicity, with a contact angle greater than 165 degrees as well as a sliding angle less than 1 degrees . On the basis of size tuning of the nano/microstructures, various contact angles and sliding angles were investigated. Furthermore, the influence of micro/nanostructures on superhydrophobicity is discussed.

Effects of hair sprays on colour perception: a hyperspectral imaging approach to shine and chroma on heads.

PubMed

Puccetti, G; Thompson, W

2017-04-01

Hair sprays apply fixative ingredients to provide hold to a hair style as well as weather resistance and optical properties such as shine. Generally, sprays distribute fine particles containing polymeric ingredients to form a thin film on the surface of hair. Different hair types require different strengths of the formed deposit on the hair surface. The present study shows how sprays also alter the visibility of the hair colour by altering the surface topology of the hair fibres. Hyperspectral imaging is used to map spectral characteristics of hair on mannequins and panelists over the curvature of heads. Spectral and spatial characteristics are measured before and after hair spray applications. The hair surface is imaged by SEM to visualize the degree of cuticle coverage. Finally, the perception of hair colour was evaluated on red-coloured mannequins by consumer questionnaire. Hair sprays deposit different degrees of fixatives, which lead to a progressive leveling of the cuticle natural tilt angle with respect to the fibre axis. As a result, shine is progressively shifting towards the region of hair colour visibility and decreases the perceived colour of hair seen by consumers. Lighter sprays show thinner film formation on the hair surface and less of a shine shift than strong hold hair sprays. Hair sprays are generally employed for hair style hold and weather resistance and considered without effect on hair colour. Our approach shows that spray-deposited films can affect colour perception by altering the microstructure of the hair surface. Thin films deposited on the hair fibre surface can partially fill gaps between cuticles, which reduces the cuticle natural angle. This partial erasure results in a angle shift of the shine regions towards the angle of internal reflection, thus decreasing the perceived hair colour regions as experienced by a group of consumers. © 2016 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

Challenges associated with insulin therapy progression among patients with type 2 diabetes: Latin American MOSAIc study baseline data.

PubMed

Linetzky, Bruno; Curtis, Brad; Frechtel, Gustavo; Montenegro, Renan; Escalante Pulido, Miguel; Stempa, Oded; de Lana, Janaina Martins; Gagliardino, Juan José

2016-01-01

Poor glycemic control in patients with type 2 diabetes is commonly recorded worldwide; Latin America (LA) is not an exception. Barriers to intensifying insulin therapy and which barriers are most likely to negatively impact outcomes are not completely known. The objective was to identify barriers to insulin progression in individuals with type 2 diabetes mellitus (T2DM) in LA countries (Mexico, Brazil, and Argentina). MOSAIc is a multinational, non-interventional, prospective, observational study aiming to identify the patient-, physician-, and healthcare-based factors affecting insulin intensification. Eligible patients were ≥18 years, had T2DM, and were treated with insulin for ≥3 months with/without oral antidiabetic drugs (OADs). Demographic, clinical, and psychosocial data were collected at baseline and regular intervals during the 24-month follow-up period. This paper however, focuses on baseline data analysis. The association between glycated hemoglobin (HbA1c) and selected covariates was assessed. A trend toward a higher level of HbA1c was observed in the LA versus non-LA population (8.40 ± 2.79 versus 8.18 ± 2.28; p ≤ 0.069). Significant differences were observed in clinical parameters, treatment patterns, and patient-reported outcomes in LA compared with the rest of the cohorts and between Mexico, Brazil, and Argentina. Higher number of insulin injections and lower number of OADs were used, whereas a lower level of knowledge and a higher level of diabetes-related distress were reported in LA. Covariates associated with HbA1c levels included age (-0.0129; p < 0.0001), number of OADs (0.0835; p = 0.0264), higher education level (-0.2261; p = 0.0101), healthy diet (-0.0555; p = 0.0083), self-monitoring blood glucose (-0.0512; p = 0.0033), hurried communication style in the process of care (0.1295; p = 0.0208), number of insulin injections (0.1616; p = 0.0088), adherence (-0.1939; p ≤ 0.0104), and not filling insulin prescription due to associated cost (0.2651; p = 0.0198). MOSAIc baseline data showed that insulin intensification in LA is not optimal and identified several conditions that significantly affect attaining appropriate HbA1c values. Tailored public health strategies, including education, should be developed to overcome such barriers. Trial Registration NCT01400971.

Photo Initiated Chemical Vapour Deposition To Increase Polymer Hydrophobicity

NASA Astrophysics Data System (ADS)

Bérard, Ariane; Patience, Gregory S.; Chouinard, Gérald; Tavares, Jason R.

2016-08-01

Apple growers face new challenges to produce organic apples and now many cover orchards with high-density polyethylene (HDPE) nets to exclude insects, rather than spraying insecticides. However, rainwater- associated wetness favours the development of apple scabs, Venturia inaequalis, whose lesions accumulate on the leaves and fruit causing unsightly spots. Treating the nets with a superhydrophobic coating should reduce the amount of water that passes through the net. Here we treat HDPE and polyethylene terephthalate using photo-initiated chemical vapour deposition (PICVD). We placed polymer samples in a quartz tube and passed a mixture of H2 and CO through it while a UVC lamp (254 nm) illuminated the surface. After the treatment, the contact angle between water droplets and the surface increased by an average of 20°. The contact angle of samples placed 70 cm from the entrance of the tube was higher than those at 45 cm and 20 cm. The PICVD-treated HDPE achieved a contact angle of 124°. Nets spray coated with a solvent-based commercial product achieved 180° but water ingress was, surprisingly, higher than that for nets with a lower contact angle.

Microfibril angle in wood of Scots pine trees (Pinus sylvestris) after irradiation from the Chernobyl nuclear reactor accident.

PubMed

Tulik, Mirela; Rusin, Aleksandra

2005-03-01

The secondary cell wall structure of tracheids of Scots pine (Pinus sylvestris L.), especially the angle of microfibrils in the S(2) layer, was examined in wood deposited prior to and after the Chernobyl accident in 1986. Microscopic analysis was carried out on wood samples collected in October 1997 from breast height of three pine trees 16, 30 and 42 years old. The polluted site was located in a distance of 5 km south from the Chernobyl nuclear power plant where radioactive contamination in 1997 was 3.7 x 10(5) kBq m(-2). Anatomical analysis showed that the structure of the secondary cell wall in tracheids formed after the Chernobyl accident was changed. Changes occurred both in S(2) and S(3) layers. The angle of microfibrils in S(2) layer in wood deposited after the Chernobyl accident was different in comparison to this measured in wood formed prior to the disaster. The intensity of the changes, i.e. alteration of the microfibrils angle in S(2) layer and unusual pattern of the S(3) layer, depended on the age of the tree and was most intensive in a young tree.

Spray-deposition and photopolymerization of organic-inorganic thiol-ene resins for fabrication of superamphiphobic surfaces.

PubMed

Xiong, Li; Kendrick, Laken L; Heusser, Hannele; Webb, Jamie C; Sparks, Bradley J; Goetz, James T; Guo, Wei; Stafford, Christopher M; Blanton, Michael D; Nazarenko, Sergei; Patton, Derek L

2014-07-09

Superamphiphobic surfaces, exhibiting high contact angles and low contact angle hysteresis to both water and low surface tension liquids, have attracted a great deal attention in recent years because of the potential of these materials in practical applications such as liquid-resistant textiles, self-cleaning surfaces, and antifouling/anticorrosion coatings. In this work, we present a simple strategy for fabricating of superamphiphobic coatings based on photopolymerization of hybrid thiol-ene resins. Spray-deposition and UV photopolymerization of thiol-ene resins containing hydrophobic silica nanoparticles and perfluorinated thiols provide a multiscale topography and low-energy surface that endows the surface with superamphiphobicity. The wettability and chemical composition of the surfaces were characterized by contact-angle goniometry and X-ray photoelectron spectroscopy, respectively. The hierarchical roughness features of the thiol-ene surfaces were investigated with field-emission scanning electron microscopy. Droplet impact and sandpaper abrasion tests indicate the coatings respectively possess a robust antiwetting behavior and good mechanical durability.

Tailored nanoporous coatings fabricated on conformable polymer substrates.

PubMed

Poxson, David J; Mont, Frank W; Cho, Jaehee; Schubert, E Fred; Siegel, Richard W

2012-11-01

Nanoporous coatings have become the subject of intense investigation, in part because they have been shown to have unique and tailorable physical properties that can depart greatly from their dense or macroscopic counterparts. Nanoporous coatings are frequently fabricated utilizing oblique-angle or glancing-angle physical vapor-phase deposition techniques. However, a significant limitation for such coatings exists; they are almost always deposited on smooth and rigid planar substrates, such as silicon and glass. This limitation greatly constrains the applicability, tailorability, functionality and even the economic viability, of such nanoporous coatings. Here, we report our findings on nanoporous/polymer composite systems (NPCS) fabricated by utilizing oblique-angle electron-beam methodology. These unique composite systems exhibit several favorable characteristics, namely, (i) fine-tuned control over coating nanoporosity and thickness, (ii) excellent adhesion between the nanoporous coating and polymer substrate, (iii) the ability to withstand significant and repeated bending, and (iv) the ability to be molded conformably on two and three-dimensional surfaces while closely retaining the composite system's designed nanoporous film structure and, hence, properties.

Granular avalanches down inclined and vibrated planes

NASA Astrophysics Data System (ADS)

Gaudel, Naïma; Kiesgen de Richter, Sébastien; Louvet, Nicolas; Jenny, Mathieu; Skali-Lami, Salaheddine

2016-09-01

In this article, we study granular avalanches when external mechanical vibrations are applied. We identify conditions of flow arrest and compare with the ones classically observed for nonvibrating granular flows down inclines [Phys. Fluids 11, 542 (1999), 10.1063/1.869928]. We propose an empirical law to describe the thickness of the deposits with the inclination angle and the vibration intensity. The link between the surface velocity and the depth of the flow highlights a competition between gravity and vibrations induced flows. We identify two distinct regimes: (a) gravity-driven flows at large angles where vibrations do not modify dynamical properties but the deposits (scaling laws in this regime are in agreement with the literature for nonvibrating granular flows) and (b) vibrations-driven flows at small angles where no flow is possible without applied vibrations (in this last regime, the flow behavior can be properly described by a vibration induced activated process). We show, in this study, that granular flows down inclined planes can be finely tuned by external mechanical vibrations.

An indicative method for determination of the most hazardous changes in slopes of the subsidence basins in underground coal mining area in Ostrava (Czech Republic).

PubMed

Marschalko, Marian; Yilmaz, Isik; Křístková, Veronika; Fuka, Matěj; Kubečka, Karel; Bouchal, Tomáš

2013-01-01

Considering growing population and decreasing mineral resource reserves, the issue of undermining has been and shall remain very topical. This study aims to identify the mutual connections between mined out panels of a deposit and the final manifestations on the ground surface related to deep black coal mining. On the grounds of the identified connections, the study describes a method to simplify a common evaluation of undermined areas according to building site categories. Within the study, a demarcation of the areas was conducted in two localities in Czech Republic influenced by the effects of undermining in the Upper-Silesian Basin. In the allotment of the CSM Mine, an area unsuitable for founding structures was defined from the centre of the worked out workings to the distance of 175 m from the panel's edge, for which the corresponding break angle is 78.3°. Similarly, in the allotment of the Paskov Mine, an area unsuitable for founding structures was determined to the distance of 500 m from the panel's edge, for which the corresponding break angle is 50.2°. This demarcation may be implemented prior to deposit mining being aware of several physical-mechanical parameters of rocks in the deposit's overburden. Having mined out a particular section of a deposit, it is recommended to verify the values of break angle using the method described herein. The study may be applied as a relatively fast and effective method to evaluate future land use for planning.

Local texture and grain boundary misorientations in high H(C) oxide superconductors

NASA Astrophysics Data System (ADS)

Kroeger, D. M.; Goyal, A.; Specht, E. D.; Tkaczyk, J. E.; Sutliff, J.; Deluca, J. A.; Wang, Z. L.; Riley, G. N., Jr.

The orientations of hundreds of contiguous grains in high J(C) TlBa2Ca2Cu3O(x) deposits and (Bi, Pb)2 Sr2Ca2Cu3O(y) powder-in-tube tapes have been determined from electron back scatter diffraction patterns (EBSP). The misorientation angles and axes of rotation (angle/axis pairs) for grain boundaries connecting these grains were calculated. For both materials the population of low angle boundaries was found to be much larger than expected from calculations based on the macroscopic texture. The TlBa2Ca2Cu3O(x) deposits exhibit pronounced local texture which has been defined by EBSP and x-ray diffraction. Locally grains show significant in-plane (a-axis) alignment even though macroscopically a-axes are random, indicating the presence of colonies of grains with similar a-axis orientations. In (Bi, Pb)2 Sr2Ca2Cu3O(x) tapes no local texture was observed. In both materials the existence of connected networks of small angle grain boundaries can be inferred. Coincident site lattice (CSL) grain boundaries are also present in higher than expected numbers. Grain boundary energy thus appears to play a significant role in enhancing the population of potentially strongly-linked boundaries. We propose that long range strongly-linked conduction occurs through a percolative network small angle (and perhaps CSL) grain boundaries.

A nomogram for interpreting slope stability of fine-grained deposits in modern and ancient-marine environments.

USGS Publications Warehouse

Booth, J.S.; Sangrey, D.A.; Fugate, J.K.

1985-01-01

This nomogram was designed to aid in interpreting the causes of mass movement in modern and ancient settings, to provide a basis for evaluating and predicting slope stability under given conditions and to further the understanding of the relationships among the several key factors that control slope stability. Design of the nomogram is based on effective stress and combines consolidation theory as applicable to depositional environments with the infinite-slope model of slope-stability analysis. If infinite-slope conditions are assumed to exist, the effective overburden stress can be used to derive a factor of safety against static slope failure by using the angle of internal friction and the slope angle. -from Authors

Tertiary basin development and tectonic implications, Whipple detachment system, Colorado River extensional corridor, California and Arizona

NASA Technical Reports Server (NTRS)

Nielson, J. E.; Beratan, K. K.

1990-01-01

This paper reports on geologic mapping, stratigraphic and structural observations, and radiometric dating of Miocene deposits of the Whipple detachment system, Colorado River extensional corridor of California and Arizona. From these data, four regions are distinguished in the study area that correspond to four Miocene depositional basins. It is shown that these basins developed in about the same positions, relative to each other and to volcanic sources, as they occupy at present. They formed in the early Miocene from a segmentation of the upper crust into blocks bounded by high-angle faults that trended both parallel and perpendicular to the direction of extension and which were terminated at middle crustal depths by a low-angle detachment fault.

Structural and optical properties of glancing angle deposited TiO2 nanowires array.

PubMed

Chinnamuthu, P; Mondal, A; Singh, N K; Dhar, J C; Das, S K; Chattopadhyay, K K

2012-08-01

TiO2 nanowires (NWs) have been synthesized by glancing angle deposition technique using e-beam evaporator. The average length 490 nm and diameter 80 nm of NWs were examined by field emission-scanning electron microscopy. Transmission electron microscopy emphasized that the NWs were widely dispersed at the top. X-ray diffraction has been carried out on the TiO2 thin film (TF) and NW array. A small blue shift of 0.03 eV was observed in Photoluminescence (PL) main band emission for TiO2 NW as compared to TiO2 TF. The high temperature annealing at 980 degrees C partially removed the oxygen vacancy from the sample, which was investigated by PL and optical absorption measurements.

Strong light coupling effect for a glancing-deposited silver nanorod array in the Kretschmann configuration

PubMed Central

2014-01-01

In this work, three slanted silver nanorod arrays (NRAs) with different thicknesses are fabricated using the glancing angle deposition method. Each silver NRA in the Kretschmann configuration is arranged to form a prism/NRA/air system. Attenuated total reflection occurs over the visible wavelengths and wide incident angles of both s- and p-polarization states. The extinctance is inversely proportional to the thickness of the Ag NRA. The thinnest NRA, with a thickness of 169 nm, exhibits strong extinctance of more than 80% over the visible wavelengths. The associated forward scatterings from the three NRAs are measured and compared under illumination with a laser beam with a wavelength of 632.8 nm. PMID:25352769

Effect of plasma pretreatment on adhesion and mechanical properties of UV-curable coatings on plastics

NASA Astrophysics Data System (ADS)

Gururaj, T.; Subasri, R.; Raju, K. R. C. Soma; Padmanabham, G.

2011-02-01

An attempt was made to study the effect of plasma surface activation on the adhesion of UV-curable sol-gel coatings on polycarbonate (PC) and polymethylmethacrylate (PMMA) substrates. The sol was synthesized by the hydrolysis and condensation of a UV-curable silane in combination with Zr-n-propoxide. Coatings deposited by dip coating were cured using UV-radiation followed by thermal curing between 80 °C and 130 °C. The effect of plasma surface treatment on the wettability of the polymer surface prior to coating deposition was followed up by measuring the water contact angle. The water contact angle on the surface of as-cleaned substrates was 80° ± 2° and that after plasma treatment was 43° ± 1° and 50° ± 2° for PC and PMMA respectively. Adhesion as well as mechanical properties like scratch resistance and taber abrasion resistance were evaluated for coatings deposited over plasma treated and untreated surfaces.

Optical and infrared properties of glancing angle-deposited nanostructured tungsten films

DOE PAGES

Ungaro, Craig; Shah, Ankit; Kravchenko, Ivan; ...

2015-02-06

For this study, nanotextured tungsten thin films were obtained on a stainless steel (SS) substrate using the glancing-angle-deposition (GLAD) method. It was found that the optical absorption and thermal emittance of the SS substrate can be controlled by varying the parameters used during deposition. Finite-difference time-domain (FDTD) simulations were used to predict the optical absorption and infrared (IR) reflectance spectra of the fabricated samples, and good agreement was found between simulated and measured data. FDTD simulations were also used to predict the effect of changes in the height and periodicity of the nanotextures. These simulations show that good control overmore » the absorption can be achieved by altering the height and periodicity of the nanostructure. These nanostructures were shown to be temperature stable up to 500°C with the addition of a protective HfO 2 layer. Finally, applications for this structure are explored, including a promising application for solar thermal energy systems.« less

Compressor Stator Time-Variant Aerodynamic Response to Upstream Rotor Wakes.

DTIC Science & Technology

1976-11-01

periodic varia t i ons in pressure , velocity and flow direction in the exit field of an upstream element , wh i ch appea r as temporall y vary ing in a...compressor features blad i ng (42 rotor blades and 40 stator vanes , NACA 65 F Series ) that is aerodynamicall y l oaded to levels that are typical of...measurements were accom- — p lished by instrumenting a pair of the NACA Series 65 stator — vanes with flush mounted Ku lite thin -line des i gn dynamic

High resolution shallow geologic characterization of a late Pleistocene eolian environment using ground penetrating radar and optically stimulated luminescence techniques: North Carolina, USA

USGS Publications Warehouse

Mallinson, D.; Mahan, S.; Moore, Christine

2008-01-01

Geophysical surveys, sedimentology, and optically-stimulated luminescence age analyses were used to assess the geologic development of a coastal system near Swansboro, NC. This area is a significant Woodland Period Native American habitation and is designated the "Broad Reach" archaeological site. 2-d and 3-d subsurface geophysical surveys were performed using a ground penetrating radar system to define the stratigraphic framework and depositional facies. Sediment samples were collected and analyzed for grain-size to determine depositional environments. Samples were acquired and analyzed using optically stimulated luminescence techniques to derive the depositional age of the various features. The data support a low eolian to shallow subtidal coastal depositional setting for this area. Li-DAR data reveal ridge and swale topography, most likely related to beach ridges, and eolian features including low-relief, low-angle transverse and parabolic dunes, blowouts, and a low-relief eolian sand sheet. Geophysical data reveal dominantly seaward dipping units, and low-angle mounded features. Sedimentological data reveal mostly moderately-well to well-sorted fine-grained symmetrical to coarse skewed sands, suggesting initial aqueous transport and deposition, followed by eolian reworking and bioturbation. OSL data indicate initial coastal deposition prior to ca. 45,000 yBP, followed by eolian reworking and low dune stabilization at ca. 13,000 to 11,500 yBP, and again at ca. 10,000 yBP (during, and slightly after the Younger Dryas chronozone).

Enhanced Performance and Flexibility of Perovskite Solar Cells Based on Microstructured Multilayer Transparent Electrodes.

PubMed

Liu, Xue; Guo, Xiaoyang; Lv, Ying; Hu, Yongsheng; Lin, Jie; Fan, Yi; Zhang, Nan; Liu, Xingyuan

2018-05-30

The performance and flexibility of perovskite solar cells (PSCs) have been enhanced by introducing microstructured WO 3 /Ag/WO 3 (WAW) multilayer transparent electrodes, which can be fabricated through glancing angle deposition (GLAD) method. The structure and morphology of the second WO 3 layers in WAW films can be altered significantly by changing the deposition angles. A film with porous, oriented WO 3 nanocolumns was obtained at the deposition angle of 75°. The rigid and flexible devices based on this microstructured electrodes show enhanced power conversion efficiencies (PCEs) of 14.91 and 13.79%, respectively, which are increasing by 10.36 and 10.14% in comparison with the devices based on the WAW electrodes with planar structure, respectively. Simultaneously, the bending stability of the flexible PSCs based on the microstructured WAW electrode has been improved significantly, which retains 90.97% of its initial PCE after 1000 times bending under the maximum strain of 1.3%, compared with the 78.39% of the reference device with the planar WAW electrode. This can be attributed to the unique microstructure of WAW electrodes fabricated by GLAD methods, releasing the mechanical stresses under repeated bending; moreover, the smaller grains induced by this electrode can disperse the stress, which decrease the damage on the perovskite layer; we believe that this work will pave for the way to improve the performance and flexibility of PSCs.

A lithium deposition system for tokamak devices*

NASA Astrophysics Data System (ADS)

Graziul, Christopher; Majeski, Richard; Kaita, Robert; Hoffman, Daniel; Timberlake, John; Card, David

2002-11-01

The production of a lithium deposition system using commercially available components is discussed. This system is intended to provide a fresh lithium wall coating between discharges in a tokamak. For this purpose, a film 100-200 Å thick is sufficient to ensure that the plasma interacts solely with the lithium. A test system consisting of a lithium evaporator and a deposition monitor has been designed and constructed to investigate deposition rates and coverage. A Thermionics 3kW e-gun is used to rapidly evaporate small amounts of solid lithium. An Inficon XTM/2 quartz deposition monitor then measures deposition rate at varying distances, positions and angles relative to the e-gun crucible. Initial results from the test system will be presented. *Supported by US DOE contract #DE-AC02-76CH-03073

Reflectance degradation of a secondary concentrator by nitrate salt vapor deposition in an open volumetric receiver configuration

NASA Astrophysics Data System (ADS)

Lahlou, Radia; Armstrong, Peter R.; Calvet, Nicolas; Shamim, Tariq

2017-06-01

Nitrate salt vapor deposition on the reflecting surface of a secondary concentrator placed on top of an open molten salt tank at 500 °C is investigated using a lab-scale setup over an 8h-exposure cycle. Deposition, consisting of mostly spherical particles, is characterized in terms of chemical composition using energy dispersive X-ray spectroscopy. The corresponding specular reflectance degradation both temporary (before washing off the salt deposits) and permanent (residual reflectance loss after cleaning), is measured at different incidence angles and at reference points located at different heights. Reflectance drop due to salt deposits is compared to the one resulting from dust deposition. Long-term reflectance degradation by means of corrosion needs to be further studied through suitable accelerated aging tests.

Sensitivity enhancement of OD- and OD-CNT-based humidity sensors by high gravity thin film deposition technique

NASA Astrophysics Data System (ADS)

Karimov, Kh. S.; Fatima, Noshin; Sulaiman, Khaulah; Mahroof Tahir, M.; Ahmad, Zubair; Mateen, A.

2015-03-01

The humidity sensing properties of the thin films of an organic semiconductor material orange dye (OD) and its composite with CNTs deposited at high gravity conditions have been reported. Impedance, phase angle, capacitance and dissipation of the samples were measured at 1 kHz and room temperature conditions. The impedance decreases and capacitance increases with an increase in the humidity level. It was found that the sensitivity of the OD-based thin film samples deposited at high gravity condition is higher than the samples deposited at low gravity condition. The impedances and capacitance sensitivities of the of the samples deposited under high gravity condition are 6.1 times and 1.6 times higher than the films deposited under low gravity condition.

Nanostructured carbon films with oriented graphitic planes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Teo, E. H. T.; Kalish, R.; Kulik, J.

2011-03-21

Nanostructured carbon films with oriented graphitic planes can be deposited by applying energetic carbon bombardment. The present work shows the possibility of structuring graphitic planes perpendicular to the substrate in following two distinct ways: (i) applying sufficiently large carbon energies for deposition at room temperature (E>10 keV), (ii) utilizing much lower energies for deposition at elevated substrate temperatures (T>200 deg. C). High resolution transmission electron microscopy is used to probe the graphitic planes. The alignment achieved at elevated temperatures does not depend on the deposition angle. The data provides insight into the mechanisms leading to the growth of oriented graphiticmore » planes under different conditions.« less

Surface modification of paper on a continuous atmospheric-pressure-plasma system

NASA Astrophysics Data System (ADS)

Cruz-Barba, Luis Emilio

Plasma technologies for the continuous modification of materials in atmospheric-pressure-plasma conditions were used to evaluate the surface modification of paper under different plasma conditions. The generation of hydrophobic layers was used to characterize the efficiency of the originally designed system for future application in the paper industry. Generation of hydrophobic layers was carried out by deposition of thin layers from fluorine containing gases, as well as cross-linking of pre-deposited thin layers of hydrophobic materials, such as fluoropolymers and silicones, in a continuous system plasma reactor (CSPR). Physical and chemical characterization of these layers was carried out by X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), scanning electron microscopy (SEM), contact angle goniometry, and water absorption evaluations. Pure gaseous CF4 and a CF4/CH4 mixture were used to deposit fluorinated layers, rendering paper surfaces with low to moderate relative surface atomic contents of fluorine (2.5 to 16.3%). Morphological characterization revealed that the deposition consists of small clusters of fluorinated species scattered on the surface. Contact angle evaluations (50°--70°) indicated a reduction in the water affinity of the paper. Thin layers of fluoropolymer pre-deposited on paper surfaces were cross-linked in the presence of CF4, CF4/CH4, and NH 3 plasmas. All of the gases proved to be effective for the cross-linking under different conditions. These cross-linked layers were determined to maintain the original polymer structure, consisting mainly of CF2-CF 2 and small quantities of CFx. Surface characterization by AFM indicated lower roughness values compared to the untreated additive-free paper (45.1 vs 67.1 nm). Paper samples treated by this approach showed a highly hydrophobic character with up to 160° contact angles, and water absorption was reduced by as much as 61.6%. Silicone layers were cross-linked in the presence of argon and oxygen plasmas. Characterization of the silicone-coated paper indicated, as in the case of fluoropolymers, the retention of the original chemical structure. Surface roughness values (AFM) were in the range of 11.8 to 18.2 nm, evidence of a very smooth surface. High hydrophobicity levels were reached, as shown by contact angles of up to 126°, and water absorption showed a maximum reduction of 76.8%.

Persisting roughness when deposition stops.

PubMed

Schwartz, Moshe; Edwards, S F

2004-12-01

Useful theories for growth of surfaces under random deposition of material have been developed by several authors. The simplest theory is that introduced by Edwards and Wilkinson (EW), which is linear and soluble. Its nonlinear generalization by Kardar, Parisi, and Zhang (KPZ) resulted in many subsequent studies. Yet both EW and KPZ theories contain an unphysical feature. When deposition of material is stopped, both theories predict that as time tends to infinity, the surface becomes flat. In fact, of course, the final surface is not flat, but simply has no gradients larger than the gradient related to the angle of repose. We modify the EW and KPZ theories to accommodate this feature and study the consequences for the simpler system which is a modification of the EW equation. In spite of the fact that the equation describing the evolution of the surface is not linear, we find that the steady state in the presence of noise is not very different in the long-wavelength limit from that of the linear EW equation. The situation is quite different from that of EW when deposition stops. Initially there is still some rearrangement of the surface, but that stops as everywhere on the surface the gradient is less than that related to the angle of repose. The most interesting feature observed after deposition stops is the emergence of history-dependent steady-state distributions.

Kinetic Monte Carlo simulations of water ice porosity: extrapolations of deposition parameters from the laboratory to interstellar space

NASA Astrophysics Data System (ADS)

Clements, Aspen R.; Berk, Brandon; Cooke, Ilsa R.; Garrod, Robin T.

2018-02-01

Using an off-lattice kinetic Monte Carlo model we reproduce experimental laboratory trends in the density of amorphous solid water (ASW) for varied deposition angle, rate and surface temperature. Extrapolation of the model to conditions appropriate to protoplanetary disks and interstellar dark clouds indicate that these ices may be less porous than laboratory ices.

IAU South West and Central Asian Regional Office of Astronomy for Development

NASA Astrophysics Data System (ADS)

Mickaelian, A. M.; Hakopian, S. A.; Farmanyan, S. V.; Mikayelyan, G. A.

2017-12-01

The International Astronomical Union (IAU) announced its Strategic Plan on Astronomy for Development in 2009, during the International Year of Astronomy (IYA). One of its main components was the creation of the Office of Astronomy for Development (OAD) and corresponding Regional Offices (ROADs) for implementation and coordination of its aims. The OAD was created in Cape Town, South Africa and later on ROADs were created in 8 regions. Since 2015, Armenia hosts one of them, IAU South West Asian (SWA), later renamed to South West and Central Asian (SWCA) ROAD. At present, already 6 countries have officially joined (Armenia, Georgia, Iran, Kazakhstan, Tajikistan, and Turkey), but the Office serves for a rather broad region, from Eastern Europe to Central Asia. Armenia's geographical location and its historical role in astronomy (both for well-known archaeoastronomical heritage and the presence of the famous Byurakan Astrophysical Observatory (BAO) founded by Viktor Ambartsumian in 1946) serve as a link between Europe and Eastern Partnership countries, Middle East and Asia in general. We run activities in 3 directions, Task Forces (TF): TF1 Universities and Research, TF2 Children and Schools and TF3 Public Outreach. We present our projects and all other accomplishments and discuss the role of our ROAD in maintaining contacts and development of astronomy in the region, as well as contacts between Europe and the Eastern Partnership countries. Most up-to-date information about the IAU SWCA ROAD is available on its webpage at http://iau-swa-road.aras.am/eng/index.php.

Gender and asthma-chronic obstructive pulmonary disease overlap syndrome.

PubMed

Wheaton, Anne G; Pleasants, Roy A; Croft, Janet B; Ohar, Jill A; Heidari, Khosrow; Mannino, David M; Liu, Yong; Strange, Charlie

2016-09-01

To assess relationships between obstructive lung diseases, respiratory symptoms, and comorbidities by gender. Data from 12 594 adult respondents to the 2012 South Carolina Behavioral Risk Factor Surveillance System telephone survey were used. Five categories of chronic obstructive airway disease (OAD) were defined: former asthma only, current asthma only, chronic obstructive pulmonary disease (COPD) only, asthma-COPD overlap syndrome (ACOS), and none. Associations of these categories with respiratory symptoms (frequent productive cough, shortness of breath, and impaired physical activities due to breathing problems), overall health, and comorbidities were assessed using multivariable logistic regression for men and women. Overall, 16.2% of men and 18.7% of women reported a physician diagnosis of COPD and/or asthma. Former asthma only was higher among men than women (4.9% vs. 3.2%, t-test p = 0.008). Current asthma only was more prevalent among women than men (7.2% vs. 4.7%, p < 0.001), as was ACOS (4.0% vs. 2.2%, p < 0.001). Having COPD only did not differ between women (4.3%) and men (4.4%). Adults with ACOS were most likely to report the 3 respiratory symptoms. COPD only and ACOS were associated with higher likelihoods of poor health and most comorbidities for men and women. Current asthma only was also associated with these outcomes among women, but not among men. In this large population-based sample, women were more likely than men to report ACOS and current asthma, but not COPD alone. Gender differences were evident between the OAD groups in sociodemographic characteristics, respiratory symptoms, and comorbidities, as well as overall health.

Frequency of self-monitoring blood glucose and attainment of HbA1c target values.

PubMed

Elgart, Jorge F; González, Lorena; Prestes, Mariana; Rucci, Enzo; Gagliardino, Juan J

2016-02-01

Test strips for self-monitoring of blood glucose (SMBG) represent in Argentina, around 50 % of diabetes treatment cost; the frequency of their use is closely associated with hyperglycemia treatment. However, the favorable impact of SMBG on attainment of HbA1c goal in different treatment conditions remains controversial. We therefore attempted to estimate the relationship between use of SMBG test strips and degree of attainment of metabolic control in an institution of our social security subsector (SSS) in which provision is fully covered and submitted to a regular audit system. Observational retrospective study using information of 657 patients with T2DM (period 2009-2010) from the database of the Diabetes and Other Cardiovascular Risk Factors Program (DICARO) of one institution of our SSS. DICARO provides-with an audit system-100 % coverage for all drugs and keeps records of clinical, metabolic and treatment data from every patient. The average monthly test strips/patient used for SMBG increased as a function of treatment intensification: Monotherapy with oral antidiabetic drugs (OAD) < combined OAD therapy < insulin treatment. In every condition, the number was larger in people with target HbA1c levels. Test strips represented the larger percentage of total prescription cost. In our population, the type of hyperglycemia treatment was the main driver of test strip use for SMBG; in every condition tested, targeted HbA1c values were associated with greater strip use. Patient education and prescription audit may optimize its use and treatment outcomes.

Low Incidence of Gastrointestinal Adverse Events Over Time with a Fixed-Ratio Combination of Insulin Glargine and Lixisenatide vs Lixisenatide Alone.

PubMed

Trujillo, Jennifer M; Roberts, Michelle; Dex, Terry; Chao, Jason; John White, Pa-C; LaSalle, James

2018-06-19

This post hoc analysis of gastrointestinal (GI) adverse events (AEs) from the phase 3 LixiLan-L (NCT02058160) and LixiLan-O (NCT02058147) trials aimed to determine the frequency and timing of nausea, vomiting, and diarrhea for iGlarLixi, a titratable, fixed-ratio combination of insulin glargine 100 U/mL (iGlar) and lixisenatide, vs iGlar alone or iGlar and lixisenatide alone, in patients with type 2 diabetes uncontrolled with oral antidiabetes drugs (OADs) or basal insulin ± OADs. In iGlarLixi-treated patients, the rate of GI AEs during initial weeks of treatment was lower vs patients treated with lixisenatide alone (9.6% and 11.7% of iGlarLixi-treated patients in LixiLan-L and LixiLan-O, respectively, vs 27.5% of lixisenatide-treated patients in LixiLan-O). Beyond Day 60, these rates were generally low and similar to those of lixisenatide. These lower rates are likely due to the gradual titration of lixisenatide in iGlarLixi. Median durations of intermittent GI AEs in the iGlarLixi arms were 6.0, 2.0 and 2.5 days (LixiLan-L), and 5.0, 1.0 and 3.5 days (LixiLan-O), respectively. iGlarLixi-associated GI AEs were transient, mostly mild or moderate in severity, and occurred mainly during initial titration. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

In vivo study of lipid synthesis and lipolysis dynamics by stimulated Raman scattering microscopy

NASA Astrophysics Data System (ADS)

Li, Xuesong; Li, Yan; He, Sicong; Chen, Congping; Qin, Zhongya; Mak, Ho Yi; Qu, Jianan Y.

2018-02-01

To understand the mechanisms of important lipid-related biological processes and diseases, it is highly demanded to study the dynamics of lipids in living biological system with high spatiotemporal resolution. However, in vivo quantitative analysis of lipid synthesis and lipolysis has been technically difficult to achieve by conventional lipid extraction and fluorescent staining methods. Recently, SRS microscopy has emerged as a powerful tool to probe small molecules with alkyne (C≡C) or deuterium (C-D) labeling in cell-silent region. The Raman tags have been used for the quantitative study of lipids in cells. In this study, we investigated metabolic dynamics of lipid droplets (LDs) by tracing the alkyne-tagged fatty acid 17-ODYA and deuterium-labeled saturated and unsaturated fatty acids PA-D31 & OA-D34 in living C. elegans. Specifically, we developed a hyperspectral SRS microscope system for LDs characterization. The system can sequentially excite and probe the stimulated Raman scattering-induced CH2 stretching of endogenous lipids information (2863 cm-1), C≡C stretching from 17-ODYA (2125 cm-1) and C-D stretching from deuterium-labeled fatty acids (2117 cm-1). We first examined the concentration levels of fatty acids in E. coli OP50. Two major lipid metabolic processes, namely uptake and turnover, were further studied in adult C. elegans. We imaged alkyne-tagged and deuterated fatty acids using SRS and traced their uptake, transportation, incorporation and turnover over time. Additionally, several other treatments including starvation were also conducted to study their effects on metabolic dynamics of pulse labeled 17-ODYA, PA-D31 and OA-D34.

Incretin-based therapy in type 2 diabetes: An evidence based systematic review and meta-analysis.

PubMed

Waldrop, Greer; Zhong, Jixin; Peters, Matthew; Goud, Aditya; Chen, Yin-Hsiu; Davis, Stephen N; Mukherjee, Bhramar; Rajagopalan, Sanjay

2018-01-01

Incretin based therapies such as dipeptidyl peptidase-4 inhibitors (DPP-4i) and glucagon-like peptide-1 receptor agonists (GLP-1Ra) are increasingly used for the treatment of Type 2 diabetes mellitus. In clinical practice and in previously performed clinical trials, these agents are often used in combination with other oral anti-diabetic agents (OADs) and Insulin. Prior meta-analytic reviews however do not adequately address the impact of background therapy and active comparator arms. Accordingly, we aimed to further investigate the efficacy of incretin based therapies by updating existing reviews by including clinical trial evidence after 2008; estimating the pooled effect of incretin therapies on glycemic efficacy and weight-loss, stratified by comparator therapy (placebo, mono-therapy, etc.), estimating the impact of background OADs and within class (GLP-1Ra or DPP-4i) comparative efficacy, on glycemia control. 82 randomized controlled trials after 2008 with glycemic control and weight loss as primary end-points were included. Both DPP-4i and GLP-1Ra reduced HbA1c, but only GLP-1Ra caused weight loss when compared to either active comparator drugs or placebo. GLP-1Ra were more effective than DPP-4i in glycemia lowering. Long acting GLP-1Ra were more effective in HbA1c lowering than short-acting agents but with similar weight loss effect. The effect of DPP-4i incretin glycemic efficacy was not modified by background therapy used in the study. Copyright © 2016. Published by Elsevier Inc.

Tandem-Mirror Ion Source

NASA Technical Reports Server (NTRS)

Biddle, A.; Stone, N.; Reasoner, D.; Chisholm, W.; Reynolds, J.

1986-01-01

Improved ion source produces beam of ions at any kinetic energy from 1 to 1,000 eV, with little spread in energy or angle. Such ion beams useful in studies of surface properties of materials, surface etching, deposition, and development of plasma-diagnostic instrumentation. Tandemmirror ion source uses electrostatic and magnetic fields to keep electrons in ionization chamber and assure uniform output ion beam having low divergence in energy and angle.

Microstructured Polymer Blend Surfaces Produced by Spraying Functional Copolymers and Their Blends

PubMed Central

Vargas-Alfredo, Nelson; Rodríguez Hernández, Juan

2016-01-01

We described the fabrication of functional and microstructured surfaces from polymer blends by spray deposition. This simple technique offers the possibility to simultaneously finely tune the microstructure as well as the surface chemical composition. Whereas at lower polymer concentration, randomly distributed surface micropatterns were observed, an increase of the concentration leads to significant changes on these structures. On the one hand, using pure homopolystyrene fiber-like structures were observed when the polymer concentration exceeded 30 mg/mL. Interestingly, the incorporation of 2,3,4,5,6-pentafluorostyrene changed the morphology, and, instead of fibers, micrometer size particles were identified at the surface. These fluorinated microparticles provide superhydrophobic properties leading to surfaces with contact angles above 165°. Equally, in addition to the microstructures provided by the spray deposition, the use of thermoresponsive polymers to fabricate interfaces with responsive properties is also described. Contact angle measurements revealed variations on the surface wettability upon heating when blends of polystyrene and polystyrene-b-poly(dimethylaminoethyl methacrylate) are employed. Finally, the use of spraying techniques to fabricate gradient surfaces is proposed. Maintaining a constant orientation, the surface topography and thus the contact angle varies gradually from the center to the edge of the film depending on the spray angle. PMID:28773555

Rutile titanium dioxide films deposited with a vacuum arc at different temperatures

NASA Astrophysics Data System (ADS)

Arias, L. Franco; Kleiman, A.; Heredia, E.; Márquez, A.

2012-06-01

Rutile crystalline phase of TiO2 has been one of the most investigated materials for medical applications. Its implementation as a surface layer on biomedical implants has shown to improve hemocompatibility and biocompatibility. In this work, titanium dioxide coatings were deposited on glass and steel 316L substrates using cathodic arc deposition. The coatings were obtained at different substrate temperatures; varying from room temperature to 600°C. The crystalline structure of the films was identified by glancing angle X-ray diffraction. Depending on the substrate material and on its temperature during the deposition process, anatase, anatse+rutile and rutile structures were observed. It was determined that rutile films can be obtained below 600 °C with this deposition method.

Effects of surface roughness and energy on ice adhesion strength

NASA Astrophysics Data System (ADS)

Zou, M.; Beckford, S.; Wei, R.; Ellis, C.; Hatton, G.; Miller, M. A.

2011-02-01

The aim of this study is to investigate the effects of surface roughness and surface energy on ice adhesion strength. Sandblasting technique was used to prepare samples with high roughness. Silicon-doped hydrocarbon and fluorinated-carbon thin films were employed to alter the surface energy of the samples. Silicon-doped hydrocarbon films were deposited by plasma-enhanced chemical vapor deposition, while fluorinated-carbon films were produced using deep reactive ion etching equipment by only activating the passivation step. Surface topographies were characterized using scanning electron microscopy and a stylus profilometer. The surface wetting properties were characterized by a video-based contact angle measurement system. The adhesion strength of ice formed from a water droplet on these surfaces was studied using a custom-built shear force test apparatus. It was found that the ice adhesion strength is correlated to the water contact angles of the samples only for surfaces with similar roughness: the ice adhesion strength decreases with the increase in water contact angle. The study also shows that smoother as-received sample surfaces have lower ice adhesion strength than the much rougher sandblasted surfaces.

Pulsed laser deposition of YBCO films on ISD MgO buffered metal tapes

NASA Astrophysics Data System (ADS)

Ma, B.; Li, M.; Koritala, R. E.; Fisher, B. L.; Markowitz, A. R.; Erck, R. A.; Baurceanu, R.; Dorris, S. E.; Miller, D. J.; Balachandran, U.

2003-04-01

Biaxially textured magnesium oxide (MgO) films deposited by inclined-substrate deposition (ISD) are desirable for rapid production of high-quality template layers for YBCO-coated conductors. High-quality YBCO films were grown on ISD MgO buffered metallic substrates by pulsed laser deposition (PLD). Columnar grains with a roof-tile surface structure were observed in the ISD MgO films. X-ray pole figure analysis revealed that the (002) planes of the ISD MgO films are tilted at an angle from the substrate normal. A small full-width at half maximum (FWHM) of approx9° was observed in the phi-scan for ISD MgO films deposited at an inclination angle of 55°. In-plane texture in the ISD MgO films developed in the first approx0.5 mum from the substrate surface, and then stabilized with further increases in film thickness. Yttria-stabilized zirconia and ceria buffer layers were deposited on the ISD MgO grown on metallic substrates prior to the deposition of YBCO by PLD. YBCO films with the c-axis parallel to the substrate normal have a unique orientation relationship with the ISD MgO films. An orientation relationship of YBCOlangle100rangleparallelMgOlangle111rangle and YBCOlangle010rangleparallelMgOlangle110rangle was measured by x-ray pole figure analyses and confirmed by transmission electron microscopy. A Tc of 91 K with a sharp transition and transport Jc of 5.5 × 105 A cm-2 at 77 K in self-field were measured on a YBCO film that was 0.46 mum thick, 4 mm wide and 10 mm long.

Density of Spray-Formed Materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kevin M. McHugh; Volker Uhlenwinkel; Nils Ellendr

2008-06-01

Spray Forming is an advanced materials processing technology that transforms molten metal into a near-net-shape solid by depositing atomized droplets onto a substrate. Depending on the application, the spray-formed material may be used in the as-deposited condition or it may undergo post-deposition processing. Regardless, the density of the as-deposited material is an important issue. Porosity is detrimental because it can significantly reduce strength, toughness, hardness and other properties. While it is not feasible to achieve fully-dense material in the as-deposited state, density greater than 99% of theoretical density is possible if the atomization and impact conditions are optimized. Thermal conditionsmore » at the deposit surface and droplet impact angle are key processing parameters that influence the density of the material. This paper examines the factors that contribute to porosity formation during spray forming and illustrates that very high as-deposited density is achieved by optimizing processing parameters.« less

Investigating the use of the dual-polarized and large incident angle of SAR data for mapping the fluvial and aeolian deposits

NASA Astrophysics Data System (ADS)

Gaber, Ahmed; Amarah, Bassam A.; Abdelfattah, Mohamed; Ali, Sarah

2017-12-01

Mapping the spatial distributions of the fluvial deposits in terms of particles size as well as imaging the near-surface features along the non-vegetated aeolian sand-sheets, provides valuable geological information. Thus this work aims at investigating the contribution of the dual-polarization SAR data in classifying and mapping the surface sediments as well as investigating the effect of the radar incident-angle on improving the images of the hidden features under the desert sand cover. For mapping the fluvial deposits, the covariance matrix ([C2]) using four dual-polarized ALOS/PALSAR-1 scenes cover the Wadi El Matulla, East Qena, Egypt were generated. This [C2] matrix was used to generate a supervised classification map with three main classes (gravel, gravel/sand and sand). The polarimetric scattering response, spectral reflectance and temperatures brightness of these 3 classes were extracted. However for the aeolian deposits investigation, two Radarsat-1 and three full-polarimetric ALOS/PALSAR-1 images, which cover the northwestern sandy part of Sinai, Egypt were calibrated, filtered, geocoded and ingested in a GIS database to image the near-surface features. The fluvial mapping results show that the values of the radar backscattered coefficient (σ°) and the degree of randomness of the obtained three classes are increasing respectively by increasing their grain size. Moreover, the large incident angle (θi = 39.7) of the Radarsat-1 image has revealed a meandering buried stream under the sand sheet of the northwestern part of Sinai. Such buried stream does not appear in the other optical, SRTM and SAR dataset. The main reason is the enhanced contrast between the low backscattered return from the revealed meandering stream and the surroundings as a result of the increased backscattering intensity, which is related to the relatively large incident angle along the undulated surface of the study area. All archaeological observations support the existence of paleo-fresh water lagoon at the northwestern corner of the study area, which might have been the discharge lagoon of the revealed hidden stream.

Dynamics of the Molten Contact Line

NASA Technical Reports Server (NTRS)

Sonin, Ain A.; Duthaler, Gregg; Liu, Michael; Torresola, Javier; Qiu, Taiqing

1999-01-01

The purpose of this program is to develop a basic understanding of how a molten material front spreads over a solid that is below its melting point, arrests, and freezes. Our hope is that the work will contribute toward a scientific knowledge base for certain new applications involving molten droplet deposition, including the "printing" of arbitrary three-dimensional objects by precise deposition of individual molten microdrops that solidify after impact. Little information is available at this time on the capillarity-driven motion and arrest of molten contact line regions. Schiaffino and Sonin investigated the arrest of the contact line of a molten microcrystalline wax spreading over a subcooled solid "target" of the same material. They found that contact line arrest takes place at an apparent liquid contact angle that depends primarily on the Stefan number S=c(T(sub f) -T(sub t)/L based on the temperature difference between the fusion point and the target temperature, and proposed that contact line arrest occurs when the liquid's dynamic contact angle approaches the angle of attack of the solidification front just behind the contact line. They also showed, however, that the conventional continuum equations and boundary conditions have no meaningful solution for this angle. The solidification front angle is determined by the heat flux just behind the contact line, and the heat flux is singular at that point. By comparing experiments with numerical computations, Schiaffino and Sonin estimated that the conventional solidification model must break down within a distance of order 0.1 - 1 microns of the contact line. The physical mechanism for this breakdown is as yet undetermined, and no first-principles theory exists for the contact angle at arrest. Schiaffino and Sonin also presented a framework for understanding how to moderate Weber number molten droplet deposition in terms of similarity laws and experimentation. The study is based on experiments with three molten materials- molten wax on solid wax, water on ice, and mercury on frozen mercury- which between them span a considerable range of the deposition/solidification similarity parameters. Correlations are obtained for the spreading velocity, spreading time scales, the spreading factor (i.e. ratio of deposited drop's final footprint radius and the drop's initial radius), post-spreading liquid oscillation amplitudes and time scales, and bulk solidification time scales. Duthaler carried out an experimental and theoretical investigation of the relationship between the liquid's apparent contact angle and the Capillary number Ca=mu U/sigma based on contact line speed, for molten materials spreading over subcooled solids. This relationship is required for modeling of melt spreading. We have adapted Voinov's methodology to the molten contact line and formulated a theoretical model for the Ca vs. contact angle relationship, based Schiaffino and Sonin#s (1997a,b) wedge-like solidification front model. With the solidification front angle taken from Schiaffino and Sonin, the model is in good agreement with the experimental results for Ca vs. contact angle. Duthaler also extended the experimental investigation of droplet deposition and contact line freezing to more materials, including solder on glass, solder on solder, water on ice, and molten microcrystalline wax on wax. The latter also included tests on inclined targets. Deposition tests have also been done with molten octacosane (C28H58) on various targets. An important objective of our program has been the development of micron-scale sensors for measuring the transient temperature at a point on the substrate surface as a molten contact line moves over it. The expectation is that this temperature history will yield a better understanding of the thermal process in the contact line region. The sensors are of the thermistor type, either 2.5 microns or 1.5 microns square, microfabricated with silicon-based technology on either pure silicon or amorphous silicon dioxide chips. Each chip has 32 sensors distributed on its surface in arrays. The time response is better than 10 ms. At the time of writing, sensor calibration is in progress. Results on thermal transients during contact line passage will be discussed at the conference. While we expect that the data will provide information on the near-contact-line heat transfer process, we also foresee possible problems. First, the spatial resolution of the sensors may be insufficient to resolve the near-contact-line region. Second, the sensors protrude about 0.5 microns above the substrate surface, and may affect the contact line motion. Third, a sensor's temperature history depends on both the heat flux distribution into it from the fusion front and the thermal properties of the substrate below it and the solidified melt between it and the fusion front. The heat flux distribution in the contact line region must therefore be unfolded from computations of the overall system's transient thermal response.

Unusual Thermal Stability of High-Entropy Alloy Amorphous Structure

DTIC Science & Technology

2012-06-20

incident angle X - ray diffractometer (GIAXRD, RIGAKU D/MAX2500) with Cu Kα radiation and at the incident angle of 1°. The surface morphology and...microanalyzer (EPMA, JEOL JAX-8800). The crystallographic structures of as-deposited and annealed metallic films were characterized utilizing a glancing ...field image and selected-area- diffraction (SAD) patterns of (a) 800 °C-, (b) 850 °C- and (c) 900 °C-annealed alloy thin films, respectively. Both

Biocompatible and Biomimetic Self-Assembly of Functional Nanostructures

DTIC Science & Technology

2010-02-28

evaporation induced self-assembly of aqueous silica precursors with a biologically compatible surfactant, glycerol monooleate ( GMO ) via dip-coating...film is first deposited, it has a relatively low contact angle with water and remains in a semi-solid state. Upon exposure to UV/ozone, the GMO begins...Figure 8. A) Water contact angle of a GMO -templated silica film as a function of UV light and ozone exposure time, B) Localization of fluorescently

Preparation of Superhydrophobic Film on Ti Substrate and Its Anticorrosion Property

PubMed Central

Zhu, Min; Tang, Wenchuan; Huang, Luyao; Zhang, Dawei; Du, Cuiwei; Yu, Gaohong; Chen, Ming; Chowwanonthapunya, Thee

2017-01-01

Superhydrophobic films were fabricated on a titanium substrate with or without anodizing by using a self-assembling method. Firstly, the pretreatments of mechanical polishing/anodizing or mechanical polishing only were conducted, respectively. Subsequently, the preparation of polydopamine film layer, deposition of nano-silver particles, and post modification of 1H,1H,2H,2H-perfluorodecanethiol were performed on the surface of the pretreated substrate. The surface morphologies, compositions, wettability, and corrosion resistance of the films were investigated with scanning electron microscopy (SEM), energy-dispersive spectrometry (EDS), water contact angle measurements, and electrochemical tests, respectively. Meanwhile, the effect of the deposition time in the silver nitrate solution on the hydrophobicity of the specimen surface was investigated. The result showed that with the increase of deposition time, the hydrophobic property enhanced gradually. The surface deposited for 7 h exhibited an optimum hydrophobic effect, which was characterized with a large water contact angle (WCA) of 154°, and the surface was rather rough and covered by a relatively uniform layer of micro-nano silver particles. The excellent hydrophobicity was attributed to a rough stratified microstructure along with the low surface energy. The electrochemical measurements showed that the existence of the superhydrophobic film can effectively enhance the corrosion resistance of Ti samples. PMID:28772987

Tilted BaHfO3 nanorod artificial pinning centres in REBCO films on inclined substrate deposited-MgO coated conductor templates

NASA Astrophysics Data System (ADS)

Stafford, B. H.; Sieger, M.; Ottolinger, R.; Meledin, A.; Strickland, N. M.; Wimbush, S. C.; Van Tendeloo, G.; Hühne, R.; Schultz, L.

2017-05-01

We grow BaHfO3 (BHO) nanorods in REBa2Cu3O7-x (REBCO, RE: Gd or Y) thin films on metal tapes coated with the inclined substrate deposited (ISD)-MgO template by both electron beam physical vapour deposition and pulsed laser deposition. In both cases the nanorods are inclined by an angle of 21°-29° with respect to the sample surface normal as a consequence of the tilted growth of the REBCO film resulting from the ISD-MgO layer. We present angular critical current density (J c) anisotropy as well as field- and temperature-dependant J c data of the BHO nanorod-containing GdBCO films demonstrating an increase in J c over a wide range of temperatures between 30 and 77 K and magnetic fields up to 8 T. In addition, we show that the angle of the peak in the J c anisotropy curve resulting from the nanorods is dependent both on temperature and magnetic field. The largest J c enhancement from the addition of the nanorods was found to occur at 30 K, 3 T, resulting in a J c of 3.0 MA cm-2.

Preparation of Superhydrophobic Film on Ti Substrate and Its Anticorrosion Property.

PubMed

Zhu, Min; Tang, Wenchuan; Huang, Luyao; Zhang, Dawei; Du, Cuiwei; Yu, Gaohong; Chen, Ming; Chowwanonthapunya, Thee

2017-06-08

Superhydrophobic films were fabricated on a titanium substrate with or without anodizing by using a self-assembling method. Firstly, the pretreatments of mechanical polishing/anodizing or mechanical polishing only were conducted, respectively. Subsequently, the preparation of polydopamine film layer, deposition of nano-silver particles, and post modification of 1H,1H,2H,2H-perfluorodecanethiol were performed on the surface of the pretreated substrate. The surface morphologies, compositions, wettability, and corrosion resistance of the films were investigated with scanning electron microscopy (SEM), energy-dispersive spectrometry (EDS), water contact angle measurements, and electrochemical tests, respectively. Meanwhile, the effect of the deposition time in the silver nitrate solution on the hydrophobicity of the specimen surface was investigated. The result showed that with the increase of deposition time, the hydrophobic property enhanced gradually. The surface deposited for 7 h exhibited an optimum hydrophobic effect, which was characterized with a large water contact angle (WCA) of 154°, and the surface was rather rough and covered by a relatively uniform layer of micro-nano silver particles. The excellent hydrophobicity was attributed to a rough stratified microstructure along with the low surface energy. The electrochemical measurements showed that the existence of the superhydrophobic film can effectively enhance the corrosion resistance of Ti samples.

Wetting behaviour of carbon nitride nanostructures grown by plasma enhanced chemical vapour deposition technique

NASA Astrophysics Data System (ADS)

Ahmad Kamal, Shafarina Azlinda; Ritikos, Richard; Abdul Rahman, Saadah

2015-02-01

Tuning the wettability of various coating materials by simply controlling the deposition parameters is essential for various specific applications. In this work, carbon nitride (CNx) films were deposited on silicon (1 1 1) substrates using radio-frequency plasma enhanced chemical vapour deposition employing parallel plate electrode configuration. Effects of varying the electrode distance (DE) on the films' structure and bonding properties were investigated using Field emission scanning electron microscopy, Atomic force microscopy, Fourier transform infrared and X-ray photoemission spectroscopy. The wettability of the films was analyzed using water contact angle measurements. At high DE, the CNx films' surface was smooth and uniform. This changed into fibrous nanostructures when DE was decreased. Surface roughness of the films increased with this morphological transformation. Nitrogen incorporation increased with decrease in DE which manifested the increase in both relative intensities of Cdbnd N to Cdbnd C and Nsbnd H to Osbnd H bonds. sp2-C to sp3-C ratio increased as DE decreased due to greater deformation of sp2 bonded carbon at lower DE. The films' characteristics changed from hydrophilic to super-hydrophobic with the decrease in DE. Roughness ratio, surface porosity and surface energy calculated from contact angle measurements were strongly dependent on the morphology, surface roughness and bonding properties of the films.

Characteristics of large three-dimensional heaps of particles produced by ballistic deposition from extended sources

NASA Astrophysics Data System (ADS)

Topic, Nikola; Gallas, Jason A. C.; Pöschel, Thorsten

2013-11-01

This paper reports a detailed numerical investigation of the geometrical and structural properties of three-dimensional heaps of particles. Our goal is the characterization of very large heaps produced by ballistic deposition from extended circular dropping areas. First, we provide an in-depth study of the formation of monodisperse heaps of particles. We find very large heaps to contain three new geometrical characteristics: they may display two external angles of repose, one internal angle of repose, and four distinct packing fraction (density) regions. Such features are found to be directly connected with the size of the dropping zone. We derive a differential equation describing the boundary of an unexpected triangular packing fraction zone formed under the dropping area. We investigate the impact that noise during the deposition has on the final heap structure. In addition, we perform two complementary experiments designed to test the robustness of the novel features found. The first experiment considers changes due to polydispersity. The second checks what happens when letting the extended dropping zone to become a point-like source of particles, the more common type of source.

Towards engineered branch placement: Unreal™ match between vapour-liquid-solid glancing angle deposition nanowire growth and simulation

NASA Astrophysics Data System (ADS)

Taschuk, M. T.; Tucker, R. T.; LaForge, J. M.; Beaudry, A. L.; Kupsta, M. R.; Brett, M. J.

2013-12-01

The vapour-liquid-solid glancing angle deposition (VLS-GLAD) process is capable of producing complex nanotree structures with control over azimuthal branch orientation and height. We have developed a thin film growth simulation including ballistic deposition, simplified surface diffusion, and droplet-mediated cubic crystal growth for the VLS-GLAD process using the UnrealTM Development Kit. The use of a commercial game engine has provided an interactive environment while allowing a custom physics implementation. Our simulation's output is verified against experimental data, including a volumetric film reconstruction produced using focused ion beam and scanning-electron microscopy (SEM), crystallographic texture, and morphological characteristics such as branch orientation. We achieve excellent morphological and texture agreement with experimental data, as well as qualitative agreement with SEM imagery. The simplified physics in our model reproduces the experimental films, indicating that the dominant role flux geometry plays in the VLS-GLAD competitive growth process responsible for azimuthally oriented branches and biaxial crystal texture evolution. The simulation's successful reproduction of experimental data indicates that it should have predictive power in designing novel VLS-GLAD structures.

A Double Selection Approach to Achieve Specific Expression of Toxin Genes for Ovarian Cancer Gene Therapy

DTIC Science & Technology

2006-11-01

fibers that served as the junction for the replacement of the OAdV7 tail domain, as well as other common sequences, is highlighted. The final Ad5Luc1-OvF...Fold increase in luciferase activity vs. Ad5 b Reference CHO Hamster ovary L/N 22 Soudais et al., 2000 RD Rhabdomyosarcoma L/N 1.5 Dmitriev et al., 1998...of OV-3 cells (human ovarian cancer, 23-fold) and CAR-deficient CHO cells (Chinese hamster ovary, 22-fold), suggesting that RD cells do not express

Lightweight Towed Howitzer Demonstrator. Phase 1 and Partial Phase 2. Volume D1. Part 1. Structural Analysis (Less Cradle and System).

DTIC Science & Technology

1987-04-01

X4Cro 7WAW,"G9 N k Y,1i ACCA . 2 JVM ly y,- L OA.0 v roo*Ler t-OAD. FA’ A /"Fi./A/a. (" -A,E’ CNAiv*6:CP A/ ’r/O’,L C4A$4P&4R.* -1MAGC.T?D0 VI.3 Moon...M- S 3D = .. = ==-=== Version 1.1 02/01/85 LTHD muzzle brate thermal load - steel Load Case 1: Loads Node F x FFM - My

Environmental Considerations and Sustainability of Base Camps in Contingency Operations

DTIC Science & Technology

2011-05-12

for failing to comply with a collection of information if it does not display a currently valid OMB control number. 1. REPORT DATE 12 MAY 2011 2 ...Seaottlllll-leo~ prDJtOnonli!X bliSo CIIIJI!N. 2 . Tho """v dlltt n ot havo on ...... stnt•gy to ellblllloh, ....aoln . oAd tnnllill011 14on...Major ObJecUve 2 ·10 ŕnstltutlonollzeContJngenct B1S1ng" lnlegroted Un II. Bua and lnstablion P1 otecbon (IU IB P) IC DT Army Enttg:f Stcuuty

Proceedings Papers of the AFSC (Air Force Systems Command) Avionics Standardization Conference (2nd) Held at Dayton, Ohio on 30 November - 2 December 1982. Volume 10. Addendum.

DTIC Science & Technology

1982-11-01

IT A REQUIREMENT, AND WILL THE PROCURING ACTIVI v MAKE IT A CRITERION IN SOURCE SELECTION? STANDARDS DE \\ : LOME’ IS A TECHNICAL ISSUE, BUT...involving an incrf Asr ,r b r-oad(-: ast (omponent. Thus our very c.unrept of syst er* r enough to "domesticate" on terra firma , now externds i nto heretofore...identify schedule critical full scale development efforts that are being done in a mature language (such as J73 or FORTRAN) and fund parallel de

Speciation in experimental C-O-H fluids produced by the thermal dissociation of oxalic acid dihydrate

NASA Astrophysics Data System (ADS)

Morgan, G. B., VI; Chou, I.-Ming; Pasteris, J. D.

1992-01-01

Fluid speciations and their related reaction pathways were studied in C-O-H-system fluids produced by the thermal dissociation of oxalic acid dihydrate (OAD: H 2C 2O 4 · 2H 2O) sealed in silica glass capsules. Experiments were conducted in the temperature range 230-750°C, with bulk fluid densities in the range 0.01-0.53 g/cm 3. Pressure was controlled by temperature and density in the isochoric systems. The quenched products of dissociation experiments were an aqueous liquid and one (supercritical fluid) or, rarely, two (vapor plus liquid) carbonic phase (s). In-situ Raman microanalyses were performed on the quenched carbonic phases at room temperature, at which fluid pressures ranged from about 50 to 340 bars. Bulk fluid speciations were reconstructed from the Raman analyses via mass balance constraints, and appear to monitor the true fluid speciations at run conditions. In experiments from the lowtemperature range (230-350°C), fluid speciations record the dissociation of OAD according to the reaction OAD = CO2 + CO + 3 H2O. A process of the form CO + H2O = CO2 + H2 is driven to the right with increasing temperature. The hydrogen gas produced tends to escape from the sample systems via diffusion into/through the silica glass capsules, shifting bulk compositions toward equimolar binary H 2O-CO 2 mixtures. The speciations of fluids in experiments with minimal hydrogen loss show poor agreement with speciations calculated for equilibrium fluids by the corresponding-states model of SAXENA and FEI (1988). Such disagreement suggests that the formations of CH 4 and graphite are metastably inhibited in the current experiments, which correlates with their absence or trivial abundances in experimental products. Moreover, calculations in which the stabilities of methane and graphite are suppressed suggest that such metastable equilibrium is approached only in experiments at temperatures greater than about 600-650°C. These results have applications to fluid processes in geological environments, in addition to considerations of using oxalate compounds as volatile sources in experimental studies. It is possible that disequilibrium or metastable fluids may be entrapped as inclusions; re-speciation (toward metastable or stable equilibrium) during P-T evolution of a given terrain would place the fluid inclusion on a new isochore that would not project through the original conditions of entrapment. Moreover, the disequilibrium to metastable nature of dissociation reactions, coupled with the diffusional mobility of hydrogen gas observed in the current experiments, suggests that the predominance of binary H 2O-CO 2 fluid mixtures in natural inclusions from medium- to high-grade metamorphic terrains may be more than a coincidence of similar initial bulk compositions.

Pattern of Onset and Risk Factors for Peripheral Oedema During Vildagliptin Use: Analysis from the Vildagliptin Prescription-Event Monitoring Study in England.

PubMed

Layton, Deborah; Coughtrie, Abigail L; Qayum, Naseer; Shakir, Saad A W

2016-11-01

Clinical trials have identified peripheral oedema (PO) as an adverse event of vildagliptin (an oral anti-diabetic drug [OAD]). A post-marketing study (PMS) was conducted to advance the understanding of vildagliptin use and particular safety concerns identified within the risk-management plan. PMS objectives included comparing the hazards between vildagliptin monotherapy and combination therapy for selected a priori identified risks, including PO. This study was a per-protocol supplementary analysis to investigate the pattern of onset and effect of vildagliptin combination therapy on PO risk. The PMS used an observational cohort design. OAD exposure, selected risk factors and outcome data were collected from general practitioners in England regarding vildagliptin users for the 6-month period after starting treatment. Data analysis comprised univariate case/non-case analysis, time-to-onset analysis and Cox proportional hazard models to estimate hazard ratios (HR) of PO adjusting for selected patients' baseline characteristics. The study cohort included 4828 patients (median age 63 years; interquartile range [IQR] 54-71), 2692 of whom were male (55.8 %). The crude cumulative hazard of PO was 19.09 cases (95 % confidence interval [CI] 13.54-26.10) per 1000 person-years; 50 % of cases occurred during the first 34 days of treatment. A significantly faster time to PO onset was observed in patients prescribed concomitant sulfonylureas versus other treatment combinations (log rank test [LRT] p = 0.0365); in patients with a prior history of PO (LRT p < 0.001), arrhythmia (LRT p = 0.0003) or hypertension (LRT p = 0.0125); and in patients aged ≥60 years (LRT p = 0.0047). Similarly, the case/non-case univariate analysis indicated that patients with PO were older; had a higher prevalence of a history of either arrhythmia, hypertension or PO; and frequently used a sulfonylurea in combination. In the hazard function analysis, only sex and prior PO history had a profound effect on risk of PO after starting vildagliptin. Furthermore, effect modification was observed between sex and prior PO history; in male patients of average age (62 years), the HR was 12.84 (95 % CI 4.96-33.23); in females, it was 1.44 (95 % CI 0.32-6.40). In this planned supplementary analysis, the findings suggest that PO occurred most frequently within 1 month after starting treatment with vildagliptin, and previous PO history and male sex in elderly patients were important predictors of this risk. The observation that concomitant use of a sulfonylurea may also increase PO risk early after starting treatment should be taken into consideration if prescribing OADs in combination with vildagliptin.

Speciation in experimental C-O-H fluids produced by the thermal dissociation of oxalic acid dihydrate

USGS Publications Warehouse

Morgan, G.B.; Chou, I.-Ming; Pasteris, J.D.

1992-01-01

Fluid speciations and their related reaction pathways were studied in C-O-H-system fluids produced by the thermal dissociation of oxalic acid dihydrate (OAD: H2C2O4 ?? 2H2O) sealed in silica glass capsules. Experiments were conducted in the temperature range 230-750??C, with bulk fluid densities in the range 0.01-0.53 g/cm3. Pressure was controlled by temperature and density in the isochoric systems. The quenched products of dissociation experiments were an aqueous liquid and one (supercritical fluid) or, rarely, two (vapor plus liquid) carbonic phase (s). In-situ Raman microanalyses were performed on the quenched carbonic phases at room temperature, at which fluid pressures ranged from about 50 to 340 bars. Bulk fluid speciations were reconstructed from the Raman analyses via mass balance constraints, and appear to monitor the true fluid speciations at run conditions. In experiments from the lowtemperature range (230-350??C), fluid speciations record the dissociation of OAD according to the reaction OAD = CO2 + CO + 3H2O. A process of the form CO + H2O = CO2 + H2 is driven to the right with increasing temperature. The hydrogen gas produced tends to escape from the sample systems via diffusion into/through the silica glass capsules, shifting bulk compositions toward equimolar binary H2O-CO2 mixtures. The speciations of fluids in experiments with minimal hydrogen loss show poor agreement with speciations calculated for equilibrium fluids by the corresponding-states model of Saxena and Fei (1988). Such disagreement suggests that the formations of CH4 and graphite are metastably inhibited in the current experiments, which correlates with their absence or trivial abundances in experimental products. Moreover, calculations in which the stabilities of methane and graphite are suppressed suggest that such metastable equilibrium is approached only in experiments at temperatures greater than about 600-650??C. These results have applications to fluid processes in geological environments, in addition to considerations of using oxalate compounds as volatile sources in experimental studies. It is possible that disequilibrium or metastable fluids may be entrapped as inclusions; re-speciation (toward metastable or stable equilibrium) during P-T evolution of a given terrain would place the fluid inclusion on a new isochore that would not project through the original conditions of entrapment. Moreover, the disequilibrium to metastable nature of dissociation reactions, coupled with the diffusional mobility of hydrogen gas observed in the current experiments, suggests that the predominance of binary H2O-CO2 fluid mixtures in natural inclusions from medium- to high-grade metamorphic terrains may be more than a coincidence of similar initial bulk compositions. ?? 1992.

Optical and hydrophobic properties of co-sputtered chromium and titanium oxynitride films

NASA Astrophysics Data System (ADS)

Rawal, Sushant K.; Chawla, Amit Kumar; Jayaganthan, R.; Chandra, Ramesh

2011-08-01

The chromium and titanium oxynitride films on glass substrate were deposited by using reactive RF magnetron sputtering in the present work. The structural and optical properties of the chromium and titanium oxynitride films as a function of power variations are investigated. The chromium oxynitride films are crystalline even at low power of Cr target (≥60 W) but the titanium oxynitride films are amorphous at low target power of Ti target (≤90 W) as observed from glancing incidence X-ray diffraction (GIXRD) patterns. The residual stress and strain of the chromium oxynitride films are calculated by sin 2 ψ method, as the average crystallite size decreases with the increase in sputtering power of the Cr target, higher stress and strain values are observed. The chromium oxynitride films changes from hydrophilic to hydrophobic with the increase of contact angle value from 86.4° to 94.1°, but the deposited titanium oxynitride films are hydrophilic as observed from contact angle measurements. The changes in surface energy were calculated using contact angle measurements to substantiate the hydrophobic properties of the films. UV-vis and NIR spectrophotometer were used to obtain the transmission and absorption spectra, and the later was used for determining band gap values of the films, respectively. The refractive index of chromium and titanium oxynitride films increases with film packing density due to formation of crystalline chromium and titanium oxynitride films with the gradual rise in deposition rate as a result of increase in target powers.

A simplified method for assessing particle deposition rate in aircraft cabins

NASA Astrophysics Data System (ADS)

You, Ruoyu; Zhao, Bin

2013-03-01

Particle deposition in aircraft cabins is important for the exposure of passengers to particulate matter, as well as the airborne infectious diseases. In this study, a simplified method is proposed for initial and quick assessment of particle deposition rate in aircraft cabins. The method included: collecting the inclined angle, area, characteristic length, and freestream air velocity for each surface in a cabin; estimating the friction velocity based on the characteristic length and freestream air velocity; modeling the particle deposition velocity using the empirical equation we developed previously; and then calculating the particle deposition rate. The particle deposition rates for the fully-occupied, half-occupied, 1/4-occupied and empty first-class cabin of the MD-82 commercial airliner were estimated. The results show that the occupancy did not significantly influence the particle deposition rate of the cabin. Furthermore, the simplified human model can be used in the assessment with acceptable accuracy. Finally, the comparison results show that the particle deposition rate of aircraft cabins and indoor environments are quite similar.

Design and fabrication of highly hydrophobic Mn nano-sculptured thin films and evaluation of surface properties on hydrophobicity

NASA Astrophysics Data System (ADS)

Hosseini, Somaye; Savaloni, Hadi; Gholipour-Shahraki, Mehran

2017-03-01

The wettability of solid surfaces is important from the aspects of both science and technology. The Mn nano-sculptured thin films were designed and fabricated by oblique angle deposition of Mn on glass substrates at room temperature. The obtained structure was characterized by field emission scanning electron microscopy and atomic force microscopy. The wettability of thin films samples was investigated by water contact angle (WCA). The 4-pointed helical star-shaped structure exhibits hydrophobicity with static WCAs of more than 133° for a 10-mg distilled water droplet. This sample also shows the rose petal effect with the additional property of high adhesion. The Mn nano-sculptured thin films also act as a sticky surface which is confirmed by hysteresis of the contact angle obtained from advancing and receding contact angles measurements. Physicochemical property of liquid phase could effectively change the contact angle, and polar solvents in contact with hydrophobic solid surfaces do not necessarily show high contact angle value.

Flexible, angle-independent, structural color reflectors inspired by morpho butterfly wings.

PubMed

Chung, Kyungjae; Yu, Sunkyu; Heo, Chul-Joon; Shim, Jae Won; Yang, Seung-Man; Han, Moon Gyu; Lee, Hong-Seok; Jin, Yongwan; Lee, Sang Yoon; Park, Namkyoo; Shin, Jung H

2012-05-08

Thin-film color reflectors inspired by Morpho butterflies are fabricated. Using a combination of directional deposition, silica microspheres with a wide size distribution, and a PDMS (polydimethylsiloxane) encasing, a large, flexible reflector is created that actually provides better angle-independent color characteristics than Morpho butterflies and which can even be bent and folded freely without losing its Morpho-mimetic photonic properties. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Geology of the Ivanhoe Hg-Au district, northern Nevada: Influence of Miocene volcanism, lakes, and active faulting on epithermal mineralization

USGS Publications Warehouse

Wallace, A.R.

2003-01-01

The mercury-gold deposits of the Ivanhoe mining district in northern Nevada formed when middle Miocene rhyolitic volcanism and high-angle faulting disrupted a shallow lacustrine environment. Sinter and replacement mercury deposits formed at and near the paleosurface, and disseminated gold deposits and high-grade gold-silver veins formed beneath the hot spring deposits. The lacustrine environment provided abundant meteoric water; the rhyolites heated the water; and the faults, flow units, and lakebeds provided fluid pathways for the hydrothermal fluids. A shallow lake began to develop in the Ivanhoe area about 16.5 Ma. The lake progressively expanded and covered the entire area with fine-grained lacustrine sediments. Lacustrine sedimentation continued to at least 14.4 Ma, and periodic fluctuations in the size and extent of the lake may have been responses to both climate and nearby volcanism. The eruption of rhyolite and andesite flows and domes periodically disrupted the lacustrine environment and produced interfingered flows and lake sediments. The major pulse of rhyolitic volcanism took place between 15.16 ± 0.05 and 14.92 ± 0.05 Ma. High-angle faulting began in the basement about 15.2 Ma, penetrated to and disrupted the paleosurface after 15.10 ± 0.06 Ma, and largely ceased by 14.92 ± 0.05 Ma. Ground motion related to both faulting and volcanism created debris flows and soft-sediment deformation in the lakebeds. Mercury-gold mineralization was coeval with rhyolite volcanism and high-angle faulting, and it took place about 15.2 to 14.9 Ma. At and near the paleosurface, hydrothermal fluids migrated through tuffaceous sediments above relatively impermeable volcanic and Paleozoic units, creating chalcedonic, cinnabar-bearing replacement bodies and sinters. Disseminated gold was deposited in sedimentary and volcanic rocks beneath the mercury deposits, although the hydrologic path between the two ore types is unclear. Higher-grade gold-silver deposits formed in massive rhyolites and Paleozoic quartzites at deeper levels, and these mineralized zones possibly represent the feeder zones for the higher-level deposits. Fluctuations in the ground-water table locally produced hydrothermal oxidation of the near-surface mercury and disseminated gold deposits. The locus of mineralization shifted with time, moving south and east from its inception point in the west-central part of the district. Thus, although mineralization in the district took place during a span of 300,000 years, the duration of mineralization at any one place probably was much shorter. The low-sulfidation deposits of the Ivanhoe district formed at the same time and under similar conditions as those in the nearby Midas district, 15 km to the northwest, which includes the large, high-grade Ken Snyder gold-silver epithermal vein deposit. The exposures in the Ivanhoe district are interpreted to represent the near-surface example of the paleosurface that originally was present above the Midas mineralizing system. The resulting combined Ivanhoe-Midas model provides an exploration guide for epithermal deposits in similar geologic environments in northern Nevada.

Predictors of early discontinuation of basal insulin therapy in type 2 diabetes in primary care.

PubMed

Kostev, K; Dippel, F W; Rathmann, W

2016-04-01

To identify patient-related characteristics and other impact factors predicting early discontinuation of basal insulin therapy in type 2 diabetes in primary care. A total of 4837 patients who started basal insulin therapy (glargine: n=3175; NPH: n=1662) in 1072 general and internal medicine practices throughout Germany were retrospectively analyzed (Disease Analyser Database: 01/2008-03/2014). Early discontinuation was defined as switching back to oral antidiabetic drugs (OAD) therapy within 90 days after first basal insulin prescription (index date, ID). Patient records were assessed 365 days prior and post ID. Logistic regression models were used to adjust for age, sex, diabetes duration, diabetologist care, disease management program participation, HbA1c, and comorbidity. Within 3 months after ID, 202 (6.8%) of glargine patients switched back to OAD (NPH: 130 (8.5%); p<0.05). In multivariable logistic regression, predictors of early basal insulin discontinuation were ≥1 documented hypoglycemia before ID (adjusted Odds ratio; 95% CI: 2.20; 1.27-3.82), diagnosed depression (1.31; 1.01-1.70) and referrals to specialists within 90 days after ID (2.06; 1.61-2.63). Diabetologist care (0.57; 0.36-0.89) and glargine treatment (vs. NPH: 0.78; 0.61-0.98) were related to a lower odds of having early insulin discontinuation. Less than 10% of type 2 diabetes patients switched back to oral antidiabetic drugs within 90 days after start of basal insulin therapy. In particular, patients with baseline depression and frequent or severe hypoglycemia have a higher likelihood for early discontinuation of basal insulin, whereas use of insulin glargine and diabetologist care are related to an increased chance of continuous insulin treatment. Copyright © 2015 Primary Care Diabetes Europe. Published by Elsevier Ltd. All rights reserved.

Acidic-basic properties of three alanine-based peptides containing acidic and basic side chains: comparison between theory and experiment.

PubMed

Makowska, Joanna; Bagińska, Katarzyna; Liwo, Adam; Chmurzyński, Lech; Scheraga, Harold A

2008-01-01

The purpose of this work was to evaluate the effect of the nature of the ionizable end groups, and the solvent, on their acid-base properties in alanine-based peptides. Hence, the acid-base properties of three alanine-based peptides: Ac-KK-(A)(7)-KK-NH(2) (KAK), Ac-OO-(A)(7)-DD-NH(2) (OAD), Ac-KK-(A)(7)-EE-NH(2) (KAE), where A, D, E, K, and O denote alanine, aspartic acid, glutamic acid, lysine, and ornithine, respectively, were determined in water and in methanol by potentiometry. With the availability of these data, the ability of two theoretical methods to simulate pH-metric titration of those peptides was assessed: (i) the electrostatically driven Monte Carlo method with the ECEPP/3 force field and the Poisson-Boltzmann approach to compute solvation energy (EDMC/PB/pH), and (ii) the molecular dynamics method with the AMBER force field and the Generalized Born model (MD/GB/pH). For OAD and KAE, pK(a1) and pK(a2) correspond to the acidic side chains. For all three compounds in both solvents, the pK(a1) value is remarkably lower than the pK(a) of a compound modeling the respective isolated side chain, which can be explained by the influence of the electrostatic field from positively charged ornithine or lysine side chains. The experimental titration curves are reproduced well by the MD/GB/pH approach, the agreement being better if restraints derived from NMR measurements are incorporated in the conformational search. Poorer agreement is achieved by the EDMC/PB/pH method.

Improving CART-Cell Therapy of Solid Tumors with Oncolytic Virus-Driven Production of a Bispecific T-cell Engager.

PubMed

Wing, Anna; Fajardo, Carlos Alberto; Posey, Avery D; Shaw, Carolyn; Da, Tong; Young, Regina M; Alemany, Ramon; June, Carl H; Guedan, Sonia

2018-05-01

T cells expressing chimeric antigen receptors (CART) have shown significant promise in clinical trials to treat hematologic malignancies, but their efficacy in solid tumors has been limited. Oncolytic viruses have the potential to act in synergy with immunotherapies due to their immunogenic oncolytic properties and the opportunity of incorporating therapeutic transgenes in their genomes. Here, we hypothesized that an oncolytic adenovirus armed with an EGFR-targeting, bispecific T-cell engager (OAd-BiTE) would improve the outcome of CART-cell therapy in solid tumors. We report that CART cells targeting the folate receptor alpha (FR-α) successfully infiltrated preestablished xenograft tumors but failed to induce complete responses, presumably due to the presence of antigen-negative cancer cells. We demonstrated that OAd-BiTE-mediated oncolysis significantly improved CART-cell activation and proliferation, while increasing cytokine production and cytotoxicity, and showed an in vitro favorable safety profile compared with EGFR-targeting CARTs. BiTEs secreted from infected cells redirected CART cells toward EGFR in the absence of FR-α, thereby addressing tumor heterogeneity. BiTE secretion also redirected CAR-negative, nonspecific T cells found in CART-cell preparations toward tumor cells. The combinatorial approach improved antitumor efficacy and prolonged survival in mouse models of cancer when compared with the monotherapies, and this was the result of an increased BiTE-mediated T-cell activation in tumors. Overall, these results demonstrated that the combination of a BiTE-expressing oncolytic virus with adoptive CART-cell therapy overcomes key limitations of CART cells and BiTEs as monotherapies in solid tumors and encourage its further evaluation in human trials. Cancer Immunol Res; 6(5); 605-16. ©2018 AACR . ©2018 American Association for Cancer Research.

Glycaemic responses in Asian and non-Asian people with type 2 diabetes initiating insulin glargine 100 units/mL: A patient-level pooled analysis of 16 randomised controlled trials.

PubMed

Chan, Juliana C N; Bunnag, Pongamorn; Chan, Siew P; Tan, Iris T I; Tsai, Shih-Tzer; Gao, Ling; Landgraf, Wolfgang

2018-01-01

To compare outcomes between Asian and non-Asian patients with type 2 diabetes (T2D) inadequately controlled on oral antidiabetic drugs (OADs) initiating insulin glargine 100 units (U)/mL (Gla-100) in randomised controlled clinical trials. Post hoc analysis of patient-level data (Asian n = 235; non-Asian n = 3351) from 16 trials. At baseline, Asian patients were younger with lower body mass index (BMI), fasting C-peptide, and fasting plasma glucose (FPG) than non-Asian patients (all P < .001). Asian patients had a higher mean glycosylated haemoglobin (HbA1c) at Week 24 and less reduction in HbA1c from baseline (7.4% vs. 7.2%; -1.3% vs. -1.6%, respectively; P = .0001), and were less likely to achieve HbA1c <7.0% (40% vs. 47%; P = .002) than non-Asian patients. Reductions in FPG and rates of hypoglycaemia were similar between Asian and non-Asian patients. Asian patients had less weight gain than non-Asian patients (+1.3 vs. +1.9 kg, respectively, P = .013). In our post hoc meta-analysis, Gla-100 effectively lowers HbA1c and FPG in Asian patients with T2D uncontrolled on OADs with similar incidence of hypoglycaemia and less absolute weight gain compared with non-Asian patients. At a similar FPG reduction, fewer Asian patients achieved HbA1c target <7.0%, suggesting that prandial glucose needs to be addressed. Copyright © 2017. Published by Elsevier B.V.

Novel Recombinant Mycobacterium bovis BCG, Ovine Atadenovirus, and Modified Vaccinia Virus Ankara Vaccines Combine To Induce Robust Human Immunodeficiency Virus-Specific CD4 and CD8 T-Cell Responses in Rhesus Macaques▿

PubMed Central

Rosario, Maximillian; Hopkins, Richard; Fulkerson, John; Borthwick, Nicola; Quigley, Máire F.; Joseph, Joan; Douek, Daniel C.; Greenaway, Hui Yee; Venturi, Vanessa; Gostick, Emma; Price, David A.; Both, Gerald W.; Sadoff, Jerald C.; Hanke, Tomáš

2010-01-01

Mycobacterium bovis bacillus Calmette-Guérin (BCG), which elicits a degree of protective immunity against tuberculosis, is the most widely used vaccine in the world. Due to its persistence and immunogenicity, BCG has been proposed as a vector for vaccines against other infections, including HIV-1. BCG has a very good safety record, although it can cause disseminated disease in immunocompromised individuals. Here, we constructed a recombinant BCG vector expressing HIV-1 clade A-derived immunogen HIVA using the recently described safer and more immunogenic BCG strain AERAS-401 as the parental mycobacterium. Using routine ex vivo T-cell assays, BCG.HIVA401 as a stand-alone vaccine induced undetectable and weak CD8 T-cell responses in BALB/c mice and rhesus macaques, respectively. However, when BCG.HIVA401 was used as a priming component in heterologous vaccination regimens together with recombinant modified vaccinia virus Ankara-vectored MVA.HIVA and ovine atadenovirus-vectored OAdV.HIVA vaccines, robust HIV-1-specific T-cell responses were elicited. These high-frequency T-cell responses were broadly directed and capable of proliferation in response to recall antigen. Furthermore, multiple antigen-specific T-cell clonotypes were efficiently recruited into the memory pool. These desirable features are thought to be associated with good control of HIV-1 infection. In addition, strong and persistent T-cell responses specific for the BCG-derived purified protein derivative (PPD) antigen were induced. This work is the first demonstration of immunogenicity for two novel vaccine vectors and the corresponding candidate HIV-1 vaccines BCG.HIVA401 and OAdV.HIVA in nonhuman primates. These results strongly support their further exploration. PMID:20375158

Association Between Loyalty to Community Pharmacy and Medication Persistence and Compliance, and the Use of Guidelines-Recommended Drugs in Type 2 Diabetes

PubMed Central

Dossa, Anara Richi; Grégoire, Jean-Pierre; Lauzier, Sophie; Guénette, Line; Sirois, Caroline; Moisan, Jocelyne

2015-01-01

Abstract Pharmacists record data on all drugs claimed and may build a personal relationship with their clients. We hypothesized that loyalty to a single pharmacy could be associated with a better quality of drug use. To assess the association between pharmacy loyalty and quality of drug use among individuals treated with oral antidiabetes drugs (OADs). This is a cohort study using Quebec Health Insurance Board data. Associations were assessed using multivariable logistic regression. New OAD users, aged ≥18 years. Individuals who filled all their prescription drugs in the same pharmacy during the first year of treatment were considered loyal. During year 2 of treatment we assessed 4 quality indicators of drug use: persistence with antidiabetes treatment, compliance with antidiabetes treatment among those considered persistent, use of an angiotensin-converting enzyme inhibitor or of an angiotensin II receptor blocker (ACEi/ARB), and use of a lipid-lowering drug. Of 124,009 individuals, 59.75% were identified as loyal. Nonloyal individuals were less likely to persist with their antidiabetes treatment (adjusted odds ratio = 0.89; 95% CI: 0.86–0.91), to comply with their antidiabetes treatment (0.82; 0.79–0.84), to use an ACEi/ARB (0.85; 0.83–0.88) and to use a lipid-lowering drug (0.83; 0.80–0.85). Quality of drug use decreased as the number of different pharmacies increased (linear contrast tests <0.001). Results underscore the important role pharmacists could play in helping their clients with chronic diseases to better manage their drug treatments. Further research is needed to determine to what extent the positive effects associated with pharmacy loyalty are specifically due to pharmacists. PMID:26166087

Association Between Loyalty to Community Pharmacy and Medication Persistence and Compliance, and the Use of Guidelines-Recommended Drugs in Type 2 Diabetes: A Cohort Study.

PubMed

Dossa, Anara Richi; Grégoire, Jean-Pierre; Lauzier, Sophie; Guénette, Line; Sirois, Caroline; Moisan, Jocelyne

2015-07-01

Pharmacists record data on all drugs claimed and may build a personal relationship with their clients. We hypothesized that loyalty to a single pharmacy could be associated with a better quality of drug use.To assess the association between pharmacy loyalty and quality of drug use among individuals treated with oral antidiabetes drugs (OADs).This is a cohort study using Quebec Health Insurance Board data. Associations were assessed using multivariable logistic regression.New OAD users, aged ≥18 years.Individuals who filled all their prescription drugs in the same pharmacy during the first year of treatment were considered loyal. During year 2 of treatment we assessed 4 quality indicators of drug use: persistence with antidiabetes treatment, compliance with antidiabetes treatment among those considered persistent, use of an angiotensin-converting enzyme inhibitor or of an angiotensin II receptor blocker (ACEi/ARB), and use of a lipid-lowering drug.Of 124,009 individuals, 59.75% were identified as loyal. Nonloyal individuals were less likely to persist with their antidiabetes treatment (adjusted odds ratio = 0.89; 95% CI: 0.86-0.91), to comply with their antidiabetes treatment (0.82; 0.79-0.84), to use an ACEi/ARB (0.85; 0.83-0.88) and to use a lipid-lowering drug (0.83; 0.80-0.85). Quality of drug use decreased as the number of different pharmacies increased (linear contrast tests <0.001).Results underscore the important role pharmacists could play in helping their clients with chronic diseases to better manage their drug treatments. Further research is needed to determine to what extent the positive effects associated with pharmacy loyalty are specifically due to pharmacists.

Impact of lorcaserin on glycemic control in overweight and obese patients with type 2 diabetes: analysis of week 52 responders and nonresponders.

PubMed

Pi-Sunyer, Xavier; Shanahan, William; Fain, Randi; Ma, Tony; Garvey, W Timothy

2016-08-01

Treatment guidelines for type 2 diabetes mellitus (T2DM) suggest weight loss as a means to maintain glycemic control. Lorcaserin has been approved for chronic weight management in the United States as an adjunct to a reduced-calorie diet and exercise, and the previous phase 3 Behavioral Modification and Lorcaserin for Obesity and Overweight Management in Diabetes Mellitus (BLOOM-DM) study has shown that, in addition to weight loss, lorcaserin is associated with improvements in glycemic parameters. In this post hoc analysis of the BLOOM-DM trial, the relationship between responder status (patients achieving ≥5% weight loss at Week 52) and glycemic and cardiometabolic parameters is evaluated. Data are presented for patients receiving lorcaserin 10 mg twice daily or placebo for 52 weeks. More than twice as many patients receiving lorcaserin plus diet and exercise counseling were classified as Week 52 responders compared to those receiving diet and exercise counseling alone (37.5% vs. 16.1%, respectively; p < 0.001), and lorcaserin Week 52 responders had greater improvements vs. placebo Week 52 responders in FPG (-38.1 mg/dL vs. -26.0 mg/dL) and HbA1c (-1.3% vs. -1.0%). Furthermore, more lorcaserin-treated Week 52 responders decreased the number of concomitant oral antidiabetic medications (OADs) used, and fewer increased the number of OADs used, compared to placebo. Unexpectedly, lorcaserin Week 52 nonresponders also had substantial reductions in glycemic levels, despite very modest weight loss. These data support lorcaserin use in overweight and obese patients with T2DM to promote weight loss and facilitate glycemic control. www.clinicaltrials.gov identifier is NCT00603291.

A comparative DFT study on CO oxidation reaction over Si-doped BC2N nanosheet and nanotube

NASA Astrophysics Data System (ADS)

Nematollahi, Parisa; Neyts, Erik C.

2018-05-01

In this study, we performed density functional theory (DFT) calculations to investigate different reaction mechanisms of CO oxidation catalyzed by the Si atom embedded defective BC2N nanostructures as well as the analysis of the structural and electronic properties. The structures of all the complexes are optimized and characterized by frequency calculations at the M062X/6-31G∗ computational level. Also, The electronic structures and thermodynamic parameters of adsorbed CO and O2 molecules over Si-doped BC2N nanostructures are examined in detail. Moreover, to investigate the curvature effect on the CO oxidation reaction, all the adsorption and CO oxidation reactions on a finite-sized armchair (6,6) Si-BC2NNT are also studied. Our results indicate that there can be two possible pathways for the CO oxidation with O2 molecule: O2(g) + CO(g) → O2(ads) + CO(ads) → CO2(g) + O(ads) and O(ads) + CO(g) → CO2(g). The first reaction proceeds via the Langmuir-Hinshelwood (LH) mechanism while the second goes through the Eley-Rideal (ER) mechanism. On the other hand, by increasing the tube diameter, the energy barrier increases due to the strong adsorption energy of the O2 molecule which is related to its dissociation over the tube surface. Our calculations indicate that the two step energy barrier of the oxidation reaction over Si-BC2NNS is less than that over the Si-BC2NNT. Hence, Si-BC2NNS may serve as an efficient and highly activated substrate to CO oxidation rather than (4,4) Si-BC2NNT.

Ca2+-Citrate Uptake and Metabolism in Lactobacillus casei ATCC 334

PubMed Central

Mortera, Pablo; Pudlik, Agata; Magni, Christian; Alarcón, Sergio

2013-01-01

The putative citrate metabolic pathway in Lactobacillus casei ATCC 334 consists of the transporter CitH, a proton symporter of the citrate-divalent metal ion family of transporters CitMHS, citrate lyase, and the membrane-bound oxaloacetate decarboxylase complex OAD-ABDH. Resting cells of Lactobacillus casei ATCC 334 metabolized citrate in complex with Ca2+ and not as free citrate or the Mg2+-citrate complex, thereby identifying Ca2+-citrate as the substrate of the transporter CitH. The pathway was induced in the presence of Ca2+ and citrate during growth and repressed by the presence of glucose and of galactose, most likely by a carbon catabolite repression mechanism. The end products of Ca2+-citrate metabolism by resting cells of Lb. casei were pyruvate, acetate, and acetoin, demonstrating the activity of the membrane-bound oxaloacetate decarboxylase complex OAD-ABDH. Following pyruvate, the pathway splits into two branches. One branch is the classical citrate fermentation pathway producing acetoin by α-acetolactate synthase and α-acetolactate decarboxylase. The other branch yields acetate, for which the route is still obscure. Ca2+-citrate metabolism in a modified MRS medium lacking a carbohydrate did not significantly affect the growth characteristics, and generation of metabolic energy in the form of proton motive force (PMF) was not observed in resting cells. In contrast, carbohydrate/Ca2+-citrate cometabolism resulted in a higher biomass yield in batch culture. However, also with these cells, no generation of PMF was associated with Ca2+-citrate metabolism. It is concluded that citrate metabolism in Lb. casei is beneficial when it counteracts acidification by carbohydrate metabolism in later growth stages. PMID:23709502

Hepatoma targeting peptide conjugated bio-reducible polymer complexed with oncolytic adenovirus for cancer gene therapy.

PubMed

Choi, Joung-Woo; Kim, Hyun Ah; Nam, Kihoon; Na, Youjin; Yun, Chae-Ok; Kim, SungWan

2015-12-28

Despite adenovirus (Ad) vector's numerous advantages for cancer gene therapy, such as high ability of endosomal escape, efficient nuclear entry mechanism, and high transduction, and therapeutic efficacy, tumor specific targeting and antiviral immune response still remain as a critical challenge in clinical setting. To overcome these obstacles and achieve cancer-specific targeting, we constructed tumor targeting bioreducible polymer, an arginine grafted bio-reducible polymer (ABP)-PEG-HCBP1, by conjugating PEGylated ABP with HCBP1 peptides which has high affinity and selectivity towards hepatoma. The ABP-PEG-HCBP1-conjugated replication incompetent GFP-expressing ad, (Ad/GFP)-ABP-PEG-HCBP1, showed a hepatoma cancer specific uptake and transduction compared to either naked Ad/GFP or Ad/GFP-ABP. Competition assays demonstrated that Ad/GFP-ABP-PEG-HCBP1-mediated transduction was specifically inhibited by HCBP1 peptide rather than coxsackie and adenovirus receptor specific antibody. In addition, ABP-PEG-HCBP1 can protect biological activity of Ad against serum, and considerably reduced both innate and adaptive immune response against Ad. shMet-expressing oncolytic Ad (oAd; RdB/shMet) complexed with ABP-PEG-HCBP1 delivered oAd efficiently into hepatoma cancer cells. The oAd/ABP-PEG-HCBP1 demonstrated enhanced cancer cell killing efficacy in comparison to oAd/ABP complex. Furthermore, Huh7 and HT1080 cancer cells treated with oAd/shMet-ABP-PEG-HCBP1 complex had significantly decreased Met and VEGF expression in hepatoma cancer, but not in non-hepatoma cancer. In sum, these results suggest that HCBP1-conjugated bioreducible polymer could be used to deliver oncolytic Ad safely and efficiently to treat hepatoma. Copyright © 2015 Elsevier B.V. All rights reserved.

Hepatoma targeting peptide conjugated bio-reducible polymer complexed with oncolytic adenovirus for cancer gene therapy

PubMed Central

Choi, Joung-Woo; Kim, Hyun Ah; Nam, Kihoon; Na, Youjin; Yun, Chae-Ok; Kim, SungWan

2015-01-01

Despite adenovirus (Ad) vector’s numerous advantages for cancer gene therapy, such as high ability of endosomal escape, efficient nuclear entry mechanism, and high transduction, and therapeutic efficacy, tumor specific targeting and antiviral immune response still remain as a critical challenge in clinical setting. To overcome these obstacles and achieve cancer-specific targeting, we constructed tumor targeting bioreducible polymer, an arginine grafted bio-reducible polymer (ABP)-PEG-HCBP1, by conjugating PEGylated ABP with HCBP1 peptides which has high affinity and selectivity towards hepatoma. The ABP-PEG-HCBP1-conjugated replication incompetent GFP-expressing ad, (Ad/GFP)-ABP-PEG-HCBP1, showed a hepatoma cancer specific uptake and transduction compared to either naked Ad/GFP or Ad/GFP-ABP. Competition assays demonstrated that Ad/GFP-ABP-PEG-HCBP1-mediated transduction was specifically inhibited by HCBP1 peptide rather than coxsackie and adenovirus receptor specific antibody. In addition, ABP-PEG-HCBP1 can protect biological activity of Ad against serum, and considerably reduced both innate and adaptive immune response against Ad. shMet-expressing oncolytic Ad (oAd; RdB/shMet) complexed with ABP-PEG-HCBP1 delivered oAd efficiently into hepatoma cancer cells. The oAd/ABP-PEG-HCBP1 demonstrated enhanced cancer cell killing efficacy in comparison to oAd/ABP complex. Furthermore, Huh7 and HT1080 cancer cells treated with oAd/shMet-ABP-PEG-HCBP1 complex had significantly decreased Met and VEGF expression in hepatoma cancer, but not in non-hepatoma cancer. In sum, these results suggest that HCBP1-conjugated bioreducible polymer could be used to deliver oncolytic Ad safely and efficiently to treat hepatoma. PMID:26437261

Optical characterization of Mg-doped ZnO thin films deposited by RF magnetron sputtering technique

DOE Office of Scientific and Technical Information (OSTI.GOV)

Singh, Satyendra Kumar; Tripathi, Shweta; Hazra, Purnima

2016-05-06

This paper reports the in-depth analysis on optical characteristics of magnesium (Mg) doped zinc oxide (ZnO) thin films grown on p-silicon (Si) substrates by RF magnetron sputtering technique. The variable angle ellipsometer is used for the optical characterization of as-deposited thin films. The optical reflectance, transmission spectra and thickness of as-deposited thin films are measured in the spectral range of 300-800 nm with the help of the spectroscopic ellipsometer. The effect of Mg-doping on optical parameters such as optical bandgap, absorption coefficient, absorbance, extinction coefficient, refractive Index and dielectric constant for as-deposited thin films are extracted to show its application inmore » optoelectronic and photonic devices.« less

Passivation of Plasmonic Colors on Bulk Silver by Atomic Layer Deposition of Aluminum Oxide.

PubMed

Guay, Jean-Michel; Killaire, Graham; Gordon, Peter G; Barry, Sean T; Berini, Pierre; Weck, Arnaud

2018-05-01

We report the passivation of angle-independent plasmonic colors on bulk silver by atomic layer deposition (ALD) of thin films of aluminum oxide. The colors are rendered by silver nanoparticles produced by laser ablation and redeposition on silver. We then apply a two-step approach to aluminum oxide conformal film formation via ALD. In the first step, a low-density film is deposited at low temperature to preserve and pin the silver nanoparticles. In the second step, a second denser film is deposited at a higher temperature to provide tarnish protection. This approach successfully protects the silver and plasmonic colors against tarnishing, humidity, and temperature, as demonstrated by aggressive exposure trials. The processing time associated with deposition of the conformal passivation layers meets industry requirements, and the approach is compatible with mass manufacturing.

The Morphology of Silver Layers on SU8 polymers prepared by Electroless Deposition

NASA Astrophysics Data System (ADS)

Dutta, Aniruddha; Yuan, Biao; Heinrich, Helge; Grabill, Chris; Williams, Henry; Kuebler, Stephen; Bhattacharya, Aniket

2010-03-01

Silver was deposited onto the functionalized surface of polymeric SU-8 where gold nanoparticles (Au-NPs) act as nucleation sites using electroless metallization chemistry. Here we report on the evolution of the nanoscale morphology of deposited Ag studied by Transmission Electron Microscopy (TEM). In TEM of sample cross sections correlations between the original gold and the silver nanoparticles were obtained while plan-view TEM results showed the distribution of nanoparticles on the surface. Scanning TEM with a high-angle annular dark field detector was used to obtain atomic number contrast. The morphology of the deposited Ag was controlled through the presence and absence of gum Arabic. The thickness and height fluctuations of the Ag layer were determined as a function of time and a statistical analysis of the growth process was conducted for the initial deposition periods.

Physical vapor deposition as a route to hidden amorphous states

PubMed Central

Dawson, Kevin J.; Kearns, Kenneth L.; Yu, Lian; Steffen, Werner; Ediger, M. D.

2009-01-01

Stable glasses of indomethacin (IMC) were prepared by using physical vapor deposition. Wide-angle X-ray scattering measurements were performed to characterize the average local structure. IMC glasses prepared at a substrate temperature of 0.84 Tg (where Tg is the glass transition temperature) and a deposition rate of 0.2 nm/s show a broad, high-intensity peak at low q values that is not present in the supercooled liquid or melt-quenched glasses. When annealed slightly above Tg, the new WAXS pattern transforms into the melt-quenched glass pattern, but only after very long annealing times. For a series of samples prepared at the lowest deposition rate, the new local packing arrangement is present only for deposition temperatures below Tg −20 K, suggesting an underlying first-order liquid-to-liquid phase transition. PMID:19666494

Nanostructured Ti-Ta thin films synthesized by combinatorial glancing angle sputter deposition

NASA Astrophysics Data System (ADS)

Motemani, Yahya; Khare, Chinmay; Savan, Alan; Hans, Michael; Paulsen, Alexander; Frenzel, Jan; Somsen, Christoph; Mücklich, Frank; Eggeler, Gunther; Ludwig, Alfred

2016-12-01

Ti-Ta alloys are attractive materials for applications in actuators as well as biomedical implants. When fabricated as thin films, these alloys can potentially be employed as microactuators, components for micro-implantable devices and coatings on surgical implants. In this study, Ti100-x Ta x (x = 21, 30) nanocolumnar thin films are fabricated by glancing angle deposition (GLAD) at room temperature using Ti73Ta27 and Ta sputter targets. Crystal structure, morphology and microstructure of the nanostructured thin films are systematically investigated by XRD, SEM and TEM, respectively. Nanocolumns of ˜150-160 nm in width are oriented perpendicular to the substrate for both Ti79Ta21 and Ti70Ta30 compositions. The disordered α″ martensite phase with orthorhombic structure is formed in room temperature as-deposited thin films. The columns are found to be elongated small single crystals which are aligned perpendicular to the (20\\bar{4}) and (204) planes of α″ martensite, indicating that the films’ growth orientation is mainly dominated by these crystallographic planes. Laser pre-patterned substrates are utilized to obtain periodic nanocolumnar arrays. The differences in seed pattern, and inter-seed distances lead to growth of multi-level porous nanostructures. Using a unique sputter deposition geometry consisting of Ti73Ta27 and Ta sputter sources, a nanocolumnar Ti-Ta materials library was fabricated on a static substrate by a co-deposition process (combinatorial-GLAD approach). In this library, a composition spread developed between Ti72.8Ta27.2 and Ti64.4Ta35.6, as confirmed by high-throughput EDX analysis. The morphology over the materials library varies from well-isolated nanocolumns to fan-like nanocolumnar structures. The influence of two sputter sources is investigated by studying the resulting column angle on the materials library. The presented nanostructuring methods including the use of the GLAD technique along with pre-patterning and a combinatorial materials library fabrication strategy offer a promising technological approach for investigating Ti-Ta thin films for a range of applications. The proposed approaches can be similarly implemented for other materials systems which can benefit from the formation of a nanocolumnar morphology.

Template-assisted growth of transparent plasmonic nanowire electrodes

NASA Astrophysics Data System (ADS)

Caterina Giordano, Maria; Repetto, Diego; Mennucci, Carlo; Carrara, Angelica; Buatier de Mongeot, Francesco

2016-12-01

Self-organized nanowire arrays are confined by glancing-angle Au deposition on nanopatterned glass templates prepared by ion beam sputtering. The semi-transparent 1D nanowire arrays are extended over large cm2 areas and are endowed with excellent electrical conductivity competitive with the best transparent conductive oxides (sheet resistance in the range of 5-20 Ohm sq-1). In addition, the nanowires support localized surface plasmon (LSP) resonances, which are easily tunable into the visible and near infrared spectrum and are selectively excited with incident light polarized perpendicularly to the wires. Such substrates, thus, behave as multifunctional nanoelectrodes, which combine good optoelectronic performance with dichroic plasmonic excitation. The electrical percolation process of the Au nanoelectrodes was monitored in situ during growth at glancing angle, both on flat and nanopatterned glass templates. In the first case, we observed a universal scaling of the differential percolation rate, independently of the glancing deposition angle, while deviations from the universal scaling were observed when Au was confined on nanopatterned templates. In the latter case, the pronounced shadowing effect promotes the growth of locally connected 1D Au nanosticks on the ‘illuminated’ ripple ridges, thus, introducing strong anisotropies with respect to the case of a 2D percolating network.

Constructing, connecting and soldering nanostructures by environmental electron beam deposition

NASA Astrophysics Data System (ADS)

Mølhave, Kristian; Nørgaard Madsen, Dorte; Dohn, Søren; Bøggild, Peter

2004-08-01

Highly conductive nanoscale deposits with solid gold cores can be made by electron beam deposition in an environmental scanning electron microscope (ESEM), suggesting the method to be used for constructing, connecting and soldering nanostructures. This paper presents a feasibility study for such applications. We identify several issues related to contamination and unwanted deposition, relevant for deposition in both vacuum (EBD) and environmental conditions (EEBD). We study relations between scan rate, deposition rate, angle and line width for three-dimensional structures. Furthermore, we measure the conductivity of deposits containing gold cores, and find these structures to be highly conductive, approaching the conductivity of solid gold and capable of carrying high current densities. Finally, we study the use of the technique for soldering nanostructures such as carbon nanotubes. Based on the presented results we are able to estimate limits for the applicability of the method for the various applications, but also demonstrate that it is a versatile and powerful tool for nanotechnology within these limits.

Study on fabrication of the superhydrophobic sol-gel films based on copper wafer and its anti-corrosive properties

NASA Astrophysics Data System (ADS)

Fan, Youhua; Li, Changzhu; Chen, Zejun; Chen, Hong

2012-06-01

In the present study, superhydrophobic copper wafer was prepared by a sol-gel deposition method. Different molar ratios of vinyltrimethoxysilane (VTES), ethanol (EtOH), water (H2O) and ammonia water (NH3·OH) were involved in this research. The morphologies, chemical compositions and hydrophobicity of the films were analyzed by scanning electron microscopy (SEM), energy dispersive X-ray detector (EDX), Fourier transfer infrared spectrometer (FTIR) and water contact angle measurement (CA). It was shown by the surface morphological study that different structures, such as pyramid-shaped protrusions, nipple-shaped protrusions or ball-shaped silica particles, were distributed on the copper substrate. The films had a high water contact angle larger than 155.4°. The durability properties revealed that the films had a good superhydrophobicity deposited in 3.5 wt.% sodium chloride solution for up to 14 days.

Electrically conductive PEDOT coating with self-healing superhydrophobicity.

PubMed

Zhu, Dandan; Lu, Xuemin; Lu, Qinghua

2014-04-29

A self-healing electrically conductive superhydrophobic poly(3,4-ethylenedioxythiophene) (PEDOT) coating has been prepared by chemical vapor deposition of a fluoroalkylsilane (POTS) onto a PEDOT film, which was obtained by electrochemical deposition. The coating not only maintained high conductivity with a low resistivity of 3.2 × 10(-4) Ω·m, but also displayed a water contact angle larger than 156° and a sliding angle smaller than 10°. After being etched with O2 plasma, the coating showed an excellent self-healing ability, spontaneously regaining its superhydrophobicity when left under ambient conditions for 20 h. This superhydrophobicity recovery process was found to be humidity-dependent, and could be accelerated and completed within 2 h under a high humidity of 84%. The coating also exhibited good superhydrophobicity recovering ability after being corroded by strong acid solution at pH 1 or strong base solution at pH 14 for 3 h.

Mathematical estimation of the level of microbial contamination on spacecraft surfaces by volumetric air sampling

NASA Technical Reports Server (NTRS)

Oxborrow, G. S.; Roark, A. L.; Fields, N. D.; Puleo, J. R.

1974-01-01

Microbiological sampling methods presently used for enumeration of microorganisms on spacecraft surfaces require contact with easily damaged components. Estimation of viable particles on surfaces using air sampling methods in conjunction with a mathematical model would be desirable. Parameters necessary for the mathematical model are the effect of angled surfaces on viable particle collection and the number of viable cells per viable particle. Deposition of viable particles on angled surfaces closely followed a cosine function, and the number of viable cells per viable particle was consistent with a Poisson distribution. Other parameters considered by the mathematical model included deposition rate and fractional removal per unit time. A close nonlinear correlation between volumetric air sampling and airborne fallout on surfaces was established with all fallout data points falling within the 95% confidence limits as determined by the mathematical model.

In-plane magnetic anisotropy and coercive field dependence upon thickness of CoFeB

NASA Astrophysics Data System (ADS)

Kipgen, Lalminthang; Fulara, Himanshu; Raju, M.; Chaudhary, Sujeet

2012-09-01

The structural and magnetic properties of as-grown 5-50 nm thin ion-beam sputter deposited transition metal-metalloid Co20Fe60B20 (CFB) films are reported in this communication. A broad peak observed at 2θ∼45° in the glancing angle X-ray diffraction pattern revealed the formation of very fine nano-sized grains embedded in majority amorphous CFB matrix. Although no magnetic field is applied during deposition, the longitudinal magneto-optic Kerr effect measurements performed at 300 K in these as-grown films clearly established the presence of in-plane uniaxial magnetic anisotropy (Ku). It is argued that this observed anisotropy is strain-induced. This is supported by the observed dependence of direction of Ku on the angle between applied magnetic field and crystallographic orientation of the underlying Si(100) substrate, and increase in the coercivity with the increase of the film thickness.

Superhydrophobic films and methods for making superhydrophobic films

DOEpatents

Aytug, Tolga; Paranthaman, Mariappan Parans; Simpson, John T.; Bogorin, Daniela Florentina

2017-09-26

This disclosure relates to methods that include depositing a first component and a second component to form a film including a plurality of nanostructures, and coating the nanostructures with a hydrophobic layer to render the film superhydrophobic. The first component and the second component can be immiscible and phase-separated during the depositing step. The first component and the second component can be independently selected from the group consisting of a metal oxide, a metal nitride, a metal oxynitride, a metal, and combinations thereof. The films can have a thickness greater than or equal to 5 nm; an average surface roughness (Ra) of from 90 to 120 nm, as measured on a 5 .mu.m.times.5 .mu.m area; a surface area of at least 20 m.sup.2/g; a contact angle with a drop of water of at least 120 degrees; and can maintain the contact angle when exposed to harsh conditions.

Magnetoplasmonic nanostructures based on nickel inverse opal slabs

NASA Astrophysics Data System (ADS)

Grunin, A. A.; Sapoletova, N. A.; Napolskii, K. S.; Eliseev, A. A.; Fedyanin, A. A.

2012-04-01

Nanostructured nickel surfaces representing periodically arranged spherical voids in a nickel film are obtained by electrochemical deposition through a self-assembled opaline template. Excitation of surface plasmon-polaritons (SPPs) on the surface of the sample is experimentally observed as the Wood's anomaly in the reflectance spectra. Transversal magneto-optical Kerr effect (TMOKE) spectra are measured at the different angles of incidence and azimuthal angles. The two- to-threefold enhancement of TMOKE caused by the excitation of mixed plasmons in two selected azimuthal configurations is observed.

Features of the corrosion protection of aluminium alloys by creation of hydrophobic coatings

NASA Astrophysics Data System (ADS)

Sinebryukhov, S. L.; Gnedenkov, S. V.; Egorkin, V. S.; Vyaliy, I. E.

2017-09-01

Results of the study of hydrophobic layers on aluminum alloy, which underwent plasma electrolytic oxidation (PEO) and subsequent deposition of the hydrophobic agent have been described. Coatings formed by deposition of dispersion of the hydrophobic agent containing SiO2 nanoparticles on the surface of the PEO-layer are characterized by high contact angles and inhibitive properties. The formed composite layers were found to be characterized with hydrophobicity and high barrier properties.

Evaluating Titan2D mass-flow model using the 1963 Little Tahoma Peak avalanches, Mount Rainier, Washington

NASA Astrophysics Data System (ADS)

Sheridan, M. F.; Stinton, A. J.; Patra, A.; Pitman, E. B.; Bauer, A.; Nichita, C. C.

2005-01-01

The Titan2D geophysical mass-flow model is evaluated by comparing its simulation results and those obtained from another flow model, FLOW3D, with published data on the 1963 Little Tahoma Peak avalanches on Mount Rainier, Washington. The avalanches, totaling approximately 10×10 6 m 3 of broken lava blocks and other debris, traveled 6.8 km horizontally and fell 1.8 km vertically ( H/ L=0.246). Velocities calculated from runup range from 24 to 42 m/s and may have been as high as 130 m/s while the avalanches passed over Emmons Glacier. Titan2D is a code for an incompressible Coulomb continuum; it is a depth-averaged, 'shallow-water', granular-flow model. The conservation equations for mass and momentum are solved with a Coulomb-type friction term at the basal interface. The governing equations are solved on multiple processors using a parallel, adaptive mesh, Godunov scheme. Adaptive gridding dynamically concentrates computing power in regions of special interest; mesh refinement and coarsening key on the perimeter of the moving avalanche. The model flow initiates as a pile defined as an ellipsoid by a height ( z) and an elliptical base defined by radii in the x and y planes. Flow parameters are the internal friction angle and bed friction angle. Results from the model are similar in terms of velocity history, lateral spreading, location of runup areas, and final distribution of the Little Tahoma Peak deposit. The avalanches passed over the Emmons Glacier along their upper flow paths, but lower in the valley they traversed stream gravels and glacial outwash deposits. This presents difficulty in assigning an appropriate bed friction angle for the entire deposit. Incorporation of variable bed friction angles into the model using GIS will help to resolve this issue.

Evaporation dynamics of a sessile droplet on glass surfaces with fluoropolymer coatings: focusing on the final stage of thin droplet evaporation.

PubMed

Gatapova, Elizaveta Ya; Shonina, Anna M; Safonov, Alexey I; Sulyaeva, Veronica S; Kabov, Oleg A

2018-03-07

The evaporation dynamics of a water droplet with an initial volume of 2 μl from glass surfaces with fluoropolymer coatings are investigated using the shadow technique and an optical microscope. The droplet profile for a contact angle of less than 5° is constructed using an image-analyzing interference technique, and evaporation dynamics are investigated at the final stage. We coated the glass slides with a thin film of a fluoropolymer by the hot-wire chemical vapor deposition method at different deposition modes depending on the deposition pressure and the temperature of the activating wire. The resulting surfaces have different structures affecting the wetting properties. Droplet evaporation from a constant contact radius mode in the early stage of evaporation was found followed by the mode where both contact angle and contact radius simultaneously vary in time (final stage) regardless of wettability of the coated surfaces. We found that depinning occurs at small contact angles of 2.2-4.7° for all samples, which are smaller than the measured receding contact angles. This is explained by imbibition of the liquid into the developed surface of the "soft" coating that leads to formation of thin droplets completely wetting the surface. The final stage, which is little discussed in the literature, is also recorded. We have singled out a substage where the contact line velocity is abruptly increasing for all coated and uncoated surfaces. The critical droplet height corresponding to the transition to this substage is about 2 μm with R/h = 107. The duration of this substage is the same for all coated and uncoated surfaces. Droplets observed at this substage for all the tested surfaces are axisymmetric. The specific evaporation rate clearly demonstrates an abrupt increase at the final substage of the droplet evaporation. The classical R 2 law is justified for the complete wetting situation where the droplet is disappearing in an axisymmetric manner.

Numerical Control Device for Preparation Nano-Carbon Granule Coating Superhydrophobic Template and Its Application

NASA Astrophysics Data System (ADS)

Shang, G. R.; Li, Y.

2017-12-01

It is one of the ways for changing surface property by fabricating superhydrophibic coating with the help of template that is made of depositing nano-carbon particles of fuel flame on substrate such as pure copper or aluminium alloy. In the process of making template, it is difficult to keep the deposition layer uniformed. In this work, the problem was solved by manufacturing a set of numerical control equipment. It has been proved by application test that the deposition layer was uniformed by means of this facility. The contact angle is more than 150°. A new way has been developed for making superhydrohibic template.

Evolution of Texture from a Single Crystal Ti-6Al-4V Substrate During Electron Beam Directed Energy Deposition

NASA Astrophysics Data System (ADS)

Butler, Todd M.; Brice, Craig A.; Tayon, Wesley A.; Semiatin, S. Lee; Pilchak, Adam L.

2017-10-01

Additive manufacturing of Ti-6Al-4V commonly produces 〈001〉 β -fiber textures aligned with the build direction. We have performed wire-feed electron beam directed energy deposition on the {112} β plane of a single prior β-grain. The build initially grew epitaxially from the substrate with the preferred 〈001〉 growth direction significantly angled away from the build direction. However, continued layer deposition drove the formation of a 〈001〉 β -fiber texture aligned with the build direction and the direction of the strongest thermal gradient.

Relation between textured surface and diffuse reflectance of Cu films

NASA Astrophysics Data System (ADS)

Shukla, Gaurav; Angappane, S.

2018-04-01

Cu nanostructures namely chevron, slanted and vertical posts deposited on Si substrate by glancing angle deposition (GLAD) technique using DC magnetron sputtering are studied to understand the optical reflectance properties of various textures. The X-ray diffraction analysis confirmed the crystalline nature of the different structures of deposited Cu films. The FESEM images confirmed the formation of chevron, slanted and vertical posts. From the optical reflectance spectra, we found that the reflectance is more for chevron than vertical and slanted posts which have almost the same reflectance over the entire wavelength. The films with chevron texture would find various applications, like, light detector, light trapping, sensors etc.

Morphology and Composition of Localized Lunar Dark Mantle Deposits With LROC Data

NASA Astrophysics Data System (ADS)

Gustafson, O.; Bell, J. F.; Gaddis, L. R.; Hawke, B. R.; Robinson, M. S.; LROC Science Team

2010-12-01

Clementine color (ultraviolet, visible or UVVIS) and Lunar Reconnaissance Orbiter (LRO) Wide Angle (WAC) and Narrow Angle (NAC) camera data provide the means to investigate localized lunar dark-mantle deposits (DMDs) of potential pyroclastic origin. Our goals are to (1) examine the morphology and physical characteristics of these deposits with LROC WAC and NAC data; (2) extend methods used in earlier studies of lunar DMDs with Clementine spectral reflectance (CSR) data; (3) use LRO WAC multispectral data to complement and extend the CSR data for compositional analyses; and (4) apply these results to identify the likely mode of emplacement and study the diversity of compositions among these deposits. Pyroclastic deposits have been recognized all across the Moon, identified by their low albedo, smooth texture, and mantling relationship to underlying features. Gaddis et al. (2003) presented a compositional analysis of 75 potential lunar pyroclastic deposits (LPDs) based on CSR measurements. New LRO camera (LROC) data permit more extensive analyses of such deposits than previously possible. Our study began with six sites on the southeastern limb of the Moon that contain nine of the cataloged 75 potential pyroclastic deposits: Humboldt (4 deposits), Petavius, Barnard, Abel B, Abel C, and Titius. Our analysis found that some of the DMDs exhibit qualities characteristic of fluid emplacement, such as flat surfaces, sharp margins, embaying relationships, and flow textures. We conclude that the localized DMDs are a complex class of features, many of which may have formed by a combination of effusive and pyroclastic emplacement mechanisms. We have extended this analysis to include additional localized DMDs from the catalog of 75 potential pyroclastic deposits. We have examined high resolution (up to 0.5 m/p) NAC images as they become available to assess the mode of emplacement of the deposits, locate potential volcanic vents, and assess physical characteristics of the DMDs such as thickness, roughness, and rock abundance. Within and around each DMD, the Clementine UVVIS multispectral mosaic (100 m/p, 5 bands at 415, 750, 900, 950, and 1000 nm) and LROC WAC multispectral image cubes (75 to 400 m/p, 7 bands at 320, 360, 415, 565, 605, 645, and 690 nm) have been used to extract spectral reflectance data. Spectral ratio plots were prepared to compare deposits and draw conclusions regarding compositional differences, such as mafic mineral or titanium content and distribution, both within and between DMDs. The result of the study will be an improved classification of these deposits in terms of emplacement mechanisms and composition, including identifying compositional affinities among DMDs and between DMDs and other volcanic deposits.

Radiative transfer modeling of dust-coated Pancam calibration target materials: Laboratory visible/near-infrared spectrogoniometry

USGS Publications Warehouse

Johnson, J. R.; Sohl-Dickstein, J.; Grundy, W.M.; Arvidson, R. E.; Bell, J.F.; Christensen, P.R.; Graff, T.; Guinness, E.A.; Kinch, K.; Morris, Robert; Shepard, M.K.

2006-01-01

Laboratory visible/near-infrared multispectral observations of Mars Exploration Rover Pancam calibration target materials coated with different thicknesses of Mars spectral analog dust were acquired under variable illumination geometries using the Bloomsburg University Goniometer. The data were fit with a two-layer radiative transfer model that combines a Hapke formulation for the dust with measured values of the substrate interpolated using a He-Torrance approach. We first determined the single-scattering albedo, phase function, opposition effect width, and amplitude for the dust using the entire data set (six coating thicknesses, three substrates, four wavelengths, and phase angles 3??-117??). The dust exhibited single-scattering albedo values similar to other Mars analog soils and to Mars Pathfinder dust and a dominantly forward scattering behavior whose scattering lobe became narrower at longer wavelengths. Opacity values for each dust thickness corresponded well to those predicted from the particles sizes of the Mars analog dust. We then restricted the number of substrates, dust thicknesses, and incidence angles input to the model. The results suggest that the dust properties are best characterized when using substrates whose reflectances are brighter and darker than those of the deposited dust and data that span a wide range of dust thicknesses. The model also determined the dust photometric properties relatively well despite limitations placed on the range of incidence angles. The model presented here will help determine the photometric properties of dust deposited on the MER rovers and to track the multiple episodes of dust deposition and erosion that have occurred at both landing sites. Copyright 2006 by the American Geophysical Union.

Classical seismic sequence stratigraphic interpretation of intraslope basin fill: Deepwater Nigeria

DOE Office of Scientific and Technical Information (OSTI.GOV)

Duncan, E.A.

Detailed interpretation of seismic facies patterns performed within the workstation environment provides an observation based methodology for constructing depositional models of turbidite and other reservoir bearing systems expected in deepwater Nigeria. The increased fidelity of the workstation allows greater detail and accuracy to be imposed onto depositional model construction by vastly improving the discrimination of depositional from structural seismic reflection geometries. In deepwater Nigeria interslope basins, depositional cyclicity is clearly indicated by vertical seismic facies successions in the same way as can be recognized in bed thickness trends from outcrop or well log data. The recognition of the seismic faciesmore » successions appears to break the stratigraphy into at least fourth and fifth order scale sequences. Highly {open_quotes}zoomed{close_quotes} instantaneous phase displays enhance the reflection character so that near outcrop scale (resolution less than 50 mters) interpretations of depositional facies can be made. Common seismic facies and geologic interpretation include: (1) low angle erosional surfaces as channel scour or mass wasting detachment; (2) low relief mounds, often in compensation cycle overlapping stacks reflecting compacted channelbelt fill; (3) unidirectional, low angle clinoform sets suggesting laterial accretion within a channel belt or possible contourite mounds; (4) abrupt, shingled blocks illustrating tilted fault blocks of small scale intraformation slumping; and (5) high reflection amplitude and continuous, parallel reflections of pelagic and hemipelagic condensed sections. There are other subtle seismic facies resolvable given the incraesed fidelity of the workstation interpretation. Mapping and translation of these geometries into more robust stratigraphic predictions should have positive impact on exploration and development success.« less

Crystalline desiccation patterns and film break up from evaporating drops on hydrophobic oxide surfaces

NASA Astrophysics Data System (ADS)

McBride, Samantha; Dash, Susmita; Khan, Sami; Varanasi, Kripa

2017-11-01

Solute-laden sessile drops evaporating on a substrate will often force crystallization of the solute at the triple phase contact line between the drop, substrate, and air in an effect similar to the ``coffee-ring'' deposition of particles from a particle-laden drop. We report new observations of ring-shaped desiccation patterns of gypsum crystals on hydrophobic oxide substrates; ceria, erbia, and silica. These surfaces have similar contact angles ( 105 degrees), and evaporation of sessile drops proceeds at the same rate and without contact angle hysteresis on all three substrates. However, despite the apparent similarity, the patterns of crystal deposits exhibit large differences across the substrates. The supersaturation and elapsed time at the onset of crystallization also varied across substrates, despite overall evaporation rates being identical. The differences in patterns can be explained in light of the position and morphology of the crystals just prior to completion of evaporation when the sessile drop has transitioned to a thin film spread over the deposit area. Break-up of this film occurs very differently on the different surfaces, and is simultaneously influenced by existing crystals while also influencing final crystalline patterns. This work was supported by the NSF GRFP.

Molecular dynamics analysis of silicon chloride ion incidence during Si etching in Cl-based plasmas: Effects of ion incident energy, angle, and neutral radical-to-ion flux ratio

NASA Astrophysics Data System (ADS)

Nakazaki, Nobuya; Eriguchi, Koji; Ono, Kouichi

2014-10-01

Profile anomalies and surface roughness are critical issues to be resolved in plasma etching of nanometer-scale microelectronic devices, which in turn requires a better understanding of the effects of ion incident energy and angle on surface reaction kinetics. This paper presents a classical molecular dynamics (MD) simulation of Si(100) etching by energetic Clx+ (x = 1-2) and SiClx+ (x = 0-4) ion beams with different incident energies Ei = 20-500 eV and angles θi = 0-85°, with and without low-energy neutral Cl radicals (neutral-to-ion flux ratios Γn/Γi = 0 and 100). An improved Stillinger-Weber interatomic potential was used for the Si/Cl system. Numerical results indicated that in Cl+, Cl2+, SiCl3+, and SiCl4+ incidences for θi = 0° and Γn/Γi = 0, the etching occurs in the whole Ei range investigated; on the other hand, in SiCl+ and SiCl2+ incidences, the deposition occurs at low Ei < 300 and 150 eV, respectively, while the etching occurs at further increased Ei. For SiCl+ and SiCl2+, the transition energies from deposition and etching become lowered for Γn/Γi = 100. Numerical results further indicated that in the SiCl+ incidence for Γn/Γi = 0, the etching occurs in the whole θi range investigated for Ei >= 300 eV; on the other hand, for Ei = 100 and 150 eV, the deposition occurs at low θi < 60° and 40°, respectively, while the etching occurs at further increased θi; in addition, for Ei <= 50 eV, the deposition occurs in the whole θi range investigated.

Observing with the Telescopi Joan Oró

NASA Astrophysics Data System (ADS)

Vilardell, F.; Colomé, J.; Sanz, J.; Gil, P.; Ribas, I.

2013-05-01

The Joan Oró Telescope (TJO) is a 0.8-m robotic telescope placed at the Montsec Astronomical Observatory (OAdM, Catalonia, Spain). In summer 2010, the TJO finished its robotization and started the scientific exploitation phase. Through internal calls for proposals, the members of the institutions involved in the project are obtaining the first scientific results. The TJO is going now one step further and is currently preparing a public call for proposals for the beginning of 2013. The procedure used to interact with the observers in this autonomous telescope will be explained. We will also describe current projects aimed at increasing the scientific return of the facility.

Light Helicopter Family Trade-Off Analysis. Volume 4. Appendix N

DTIC Science & Technology

1985-05-15

Figur«! N -V1I-9 through N -VII-U ahow th« futl flow CMp«rlsoas chac comt|>oad r.o th« powar r«qutr«««nt* thown by flguraa (J-VII-l through M-VII-4...HELICOPTER. FAMILY TRADE-OFF ANALYSIS APPENDIX N VOLUME IV ACN: 69396 • Copy l_Q] of 130 c:optea. 15 Nay 198S ~ .. 8 06 .0&1 OTIC ELECTE AU613...TITLE (- ..... do) I. TYPf ’!! ~POitT a PI!I’IOD COVI:IU!O LIGHT HELICOPTER FAMILY TRADE-OFF ANALYSIS, Fina t y Report, APPENDIX N , VOLUME IV of XI

Effect of substrate roughness on the apparent surface free energy of sputter deposited superhydrophobic polytetrafluoroethylene coatings: A comparison of experimental data with different theoretical models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Selvakumar, N.; Barshilia, Harish C.; Rajam, K. S.

2010-07-15

We have studied the effect of substrate roughness on the wettability and the apparent surface free energy (SFE) of sputter deposited polytetrafluoroethylene (PTFE) coatings deposited on untreated glass (average roughness, R{sub a}=2.0 nm), plasma etched glass (R{sub a}=7.4 nm), and sandblasted glass (R{sub a}=4500 nm) substrates. The wettability of the PTFE coatings deposited on substrates with varying roughnesses was evaluated by measuring the apparent contact angle (CA) using a series of probe liquids from nonpolar aprotic to polar protic. The wettability measurements indicate that an apparent water CA of 152 deg. with a sliding angle of 8 deg. was achievedmore » for PTFE coatings deposited on a substrate with R{sub a}=4500 nm. The superhydrophobicity observed in these coatings is attributed to the presence of dual scale roughness, densely packed microstructure and the presence of CF{sub 3} groups. Unlike the bulk PTFE which is mainly dispersive, the sputter deposited PTFE coatings are expected to have some degree of polar component due to the plasma treatment. In order to calculate the dispersive SFE of PTFE coatings, we have used the Girifalco-Good-Fowkes (GGF) method and validated it with the Zisman model. Furthermore, the Owens-Wendt model has been used to calculate the dispersive and the polar components of the apparent SFE of the PTFE coatings. These results are further corroborated using the Fowkes method. Finally, an ''equation of state'' theory proposed by Neumann has been used to calculate the apparent SFE values of the PTFE coatings. The results indicate that the apparent SFE values of the PTFE coatings obtained from the Owens-Wendt and the Fowkes methods are comparable to those obtained from the Neumann's method. The analyses further demonstrate that the GGF and the Zisman methods underestimate the apparent SFE values of the sputter deposited PTFE coatings.« less

Characterization for elastic constants of fused deposition modelling-fabricated materials based on the virtual fields method and digital image correlation

NASA Astrophysics Data System (ADS)

Cao, Quankun; Xie, Huimin

2017-12-01

Fused deposition modelling (FDM), a widely used rapid prototyping process, is a promising technique in manufacturing engineering. In this work, a method for characterizing elastic constants of FDM-fabricated materials is proposed. First of all, according to the manufacturing process of FDM, orthotropic constitutive model is used to describe the mechanical behavior. Then the virtual fields method (VFM) is applied to characterize all the mechanical parameters (Q_{11}, Q_{22}, Q_{12}, Q_{66}) using the full-field strain, which is measured by digital image correlation (DIC). Since the principal axis of the FDM-fabricated structure is sometimes unknown due to the complexity of the manufacturing process, a disk in diametrical compression is used as the load configuration so that the loading angle can be changed conveniently. To verify the feasibility of the proposed method, finite element method (FEM) simulation is conducted to obtain the strain field of the disk. The simulation results show that higher accuracy can be achieved when the loading angle is close to 30°. Finally, a disk fabricated by FDM was used for the experiment. By rotating the disk, several tests with different loading angles were conducted. To determine the position of the principal axis in each test, two groups of parameters (Q_{11}, Q_{22}, Q_{12}, Q_{66}) are calculated by two different groups of virtual fields. Then the corresponding loading angle can be determined by minimizing the deviation between two groups of the parameters. After that, the four constants (Q_{11}, Q_{22}, Q_{12}, Q_{66}) were determined from the test with an angle of 27°.

Dual-scale rough multifunctional superhydrophobic ITO coatings prepared by air annealing of sputtered indium-tin alloy thin films

NASA Astrophysics Data System (ADS)

Gupta, Nitant; Sasikala, S.; Mahadik, D. B.; Rao, A. V.; Barshilia, Harish C.

2012-10-01

A novel method to fabricate multifunctional indium tin oxide (ITO) coatings is discussed. Superhydrophobic ITO coatings are fabricated by radio frequency balanced magnetron sputter deposition of indium-tin alloy on glass substrates followed by complete oxidation of the samples in air. The chemical nature and structure of the coatings are verified by X-ray diffraction, X-ray photoelectron spectroscopy and micro-Raman spectroscopy. Field emission scanning electron microscopic studies of the coatings display rod-like and blob-like microstructures, together with fractal-like nanostructures infused on top. Microscale roughness of the ITO coatings is measured by three-dimensional profilometry and is found to be in the range of 0.1-3 μm. Thus the presence of micro- and nano- sized structures result in dual-scale roughness. The variation in the contact angle with the deposition time is studied using a contact angle goniometer. High water contact angles (>160°) and low contact angle hysteresis (5°) are obtained at an optimum microscale roughness. The ITO coatings also exhibit other functional properties, such as low sheet resistance and semi-transparent behaviour in the visible region. The loss in the transparency of the ITO coatings is attributed to the presence of higher scale of roughness. The photoluminescence measurements show large photoemission in the visible region. It is expected that further improvements in the multifunctional properties of transparent conducting oxides will open new frontiers in designing novel materials with exotic properties.

Plasma-enhanced chemical vapor deposition of multiwalled carbon nanofibers.

PubMed

Matthews, Kristopher; Cruden, Brett A; Chen, Bin; Meyyappan, M; Delzeit, Lance

2002-10-01

Plasma-enhanced chemical vapor deposition is used to grow vertically aligned multiwalled carbon nanofibers (MWNFs). The graphite basal planes in these nanofibers are not parallel as in nanotubes; instead they exhibit a small angle resembling a stacked cone arrangement. A parametric study with varying process parameters such as growth temperature, feedstock composition, and substrate power has been conducted, and these parameters are found to influence the growth rate, diameter, and morphology. The well-aligned MWNFs are suitable for fabricating electrode systems in sensor and device development.

Plasma-enhanced chemical vapor deposition of multiwalled carbon nanofibers

NASA Technical Reports Server (NTRS)

Matthews, Kristopher; Cruden, Brett A.; Chen, Bin; Meyyappan, M.; Delzeit, Lance

2002-01-01

Plasma-enhanced chemical vapor deposition is used to grow vertically aligned multiwalled carbon nanofibers (MWNFs). The graphite basal planes in these nanofibers are not parallel as in nanotubes; instead they exhibit a small angle resembling a stacked cone arrangement. A parametric study with varying process parameters such as growth temperature, feedstock composition, and substrate power has been conducted, and these parameters are found to influence the growth rate, diameter, and morphology. The well-aligned MWNFs are suitable for fabricating electrode systems in sensor and device development.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Son, Young-Sun; Yoon, Wang-Jung

The purpose of this study is to map pyprophyllite distribution at surface of the Nohwa deposit, Korea by using Advanced Spaceborne Thermal Emission and Reflectance Radiometer (ASTER) data. For this, combined Spectral Angle Mapper (SAM), and Matched Filtering (MF) technique based on mathematical algorithm was applied. The regional distribution of high-grade and low-grade pyrophyllite in the Nohwa deposit area could be differentiated by this method. The results of this study show that ASTER data analysis using combination of SAM and MF techniques will assist in exploration of pyrophyllite at the exposed surface.

Large area multi-channel plasmonic absorber based on the touching triangular dimers fabricated by angle controlled colloidal nanolithography

NASA Astrophysics Data System (ADS)

Hamidi, S. M.; Behjati, S.

2018-02-01

Here we introduce large area plasmonic touching triangular dimers by angle controlled colloidal nanolithography to use them as an efficient multi channel absorber and also high figure of merit sensors. For this purpose, we coated gold thin films onto nanometric and also micrometric polystyrene hexagonal closed packed masks in different deposition angles and also diverse substrate polar angles. Our prepared samples, after remove masks, show large area touching triangular pattern with different inter particle distances in greater polar angles. To get more sense about optical response of the samples such as transmittance and also electric field distribution, we use finite difference time domain method in simulation part. The transmittance plot shows one narrow or multi-channel adjustable deep depend on inter-particle distances which can be controlled by azimuthally angle in nano lithography process. Also, due to the isoelliptical points in the transmittance spectra; we can see the bright and dark plasmon modes coupling and thus the Fano like resonance takes place in the optical spectral region which is very useful for refractive index measurement.

Impact of substrate off-angle on the m-plane GaN Schottky diodes

NASA Astrophysics Data System (ADS)

Yamada, Hisashi; Chonan, Hiroshi; Takahashi, Tokio; Shimizu, Mitsuaki

2018-04-01

We investigated the effects of the substrate off-angle on the m-plane GaN Schottky diodes. GaN epitaxial layers were grown by metal-organic chemical vapor deposition on m-plane GaN substrates having an off-angle of 0.1, 1.1, 1.7, or 5.1° toward [000\\bar{1}]. The surface of the GaN epitaxial layers on the 0.1°-off substrate consisted of pyramidal hillocks and contained oxygen (>1017 cm-3) and carbon (>1016 cm-3) impurities. The residual carbon and oxygen impurities decreased to <1016 cm-3 when the off-angle of the m-plane GaN substrate was increased. The leakage current of the 0.1°-off m-plane GaN Schottky diodes originated from the +c facet of the pyramidal hillocks. The leakage current was efficiently suppressed through the use of an off-angle that was observed to be greater than 1.1°. The off-angle of the m-plane GaN substrate is critical in obtaining high-performance Schottky diodes.

A generalized theory of thin film growth

NASA Astrophysics Data System (ADS)

Du, Feng; Huang, Hanchen

2018-03-01

This paper reports a theory of thin film growth that is generalized for arbitrary incidence angle during physical vapor deposition in two dimensions. The accompanying kinetic Monte Carlo simulations serve as verification. A special theory already exists for thin film growth with zero incidence angle, and another theory also exists for nanorod growth with a glancing angle. The theory in this report serves as a bridge to describe the transition from thin film growth to nanorod growth. In particular, this theory gives two critical conditions in analytical form of critical coverage, ΘI and ΘII. The first critical condition defines the onset when crystal growth or step dynamics stops following the wedding cake model for thin film growth. The second critical condition defines the onset when multiple-layer surface steps form to enable nanorod growth. Further, this theory also reveals a critical incidence angle, below which nanorod growth is impossible. The critical coverages, together with the critical incidence angle, defines a phase diagram of thin growth versus nanorod growth.

Angle-selective optical filter for highly sensitive reflection photoplethysmogram

PubMed Central

Hwang, Chan-Sol; Yang, Sung-Pyo; Jang, Kyung-Won; Park, Jung-Woo; Jeong, Ki-Hun

2017-01-01

We report an angle-selective optical filter (ASOF) for highly sensitive reflection photoplethysmography (PPG) sensors. The ASOF features slanted aluminum (Al) micromirror arrays embedded in transparent polymer resin, which effectively block scattered light under human tissue. The device microfabrication was done by using geometry-guided resist reflow of polymer micropatterns, polydimethylsiloxane replica molding, and oblique angle deposition of thin Al film. The angular transmittance through the ASOF is precisely controlled by the angle of micromirrors. For the mirror angle of 30 degrees, the ASOF accepts an incident light between - 90 to + 50 degrees and the maximum transmittance at - 55 degrees. The ASOF exhibits the substantial reduction of both the in-band noise of PPG signals over a factor of two and the low-frequency noise by three times. Consequently, this filter allows distinguishing the diastolic peak that allows miscellaneous parameters with diverse vascular information. This optical filter provides a new opportunity for highly sensitive PPG monitoring or miscellaneous optical tomography. PMID:29082070

Effect of argon ion activity on the properties of Y 2O 3 thin films deposited by low pressure PACVD

NASA Astrophysics Data System (ADS)

Barve, S. A.; Jagannath; Deo, M. N.; Kishore, R.; Biswas, A.; Gantayet, L. M.; Patil, D. S.

2010-10-01

Yttrium oxide thin films are deposited by microwave electron cyclotron resonance (ECR) plasma assisted metal organic chemical vapour deposition process using an indegeneously developed Y(thd) 3 {(2,2,6,6-tetramethyl-3,5-heptanedionate)yttrium} precursor. Depositions were carried out at two different argon gas flow rates keeping precursor and oxygen gas flow rate constant. The deposited coatings are characterized by X-ray photoelectron spectroscopy (XPS), glancing angle X-ray diffraction (GIXRD) and infrared spectroscopy. Optical properties of the films are studied by spectroscopic ellipsometry. Hardness and elastic modulus of the films are measured by load depth sensing nanoindentation technique. Stability of the film and its adhesion with the substrate is inferred from the nanoscratch test. It is shown here that, the change in the argon gas flow rates changes the ionization of the gas in the microwave ECR plasma and imposes a drastic change in the characteristics like composition, structure as well as mechanical properties of the deposited film.

Sedimentology of gravelly Lake Lahontan highstand shoreline deposits, Churchill Butte, Nevada, USA

NASA Astrophysics Data System (ADS)

Blair, Terence C.

1999-02-01

Gravelly shoreline deposits of the latest Pleistocene highstand of Lake Lahontan occur in pristine depositional morphology, and are exposed in gravel pits along Churchill Butte in west-central Nevada. Four environments differentiated at this site are alluvial fan/colluvium, lakeshore barrier spit, lake lower-shoreface spit platform, and lake bottom. Lakeshore deposits abut, along erosional wave headcuts, either unsorted muddy to bouldery colluvium fringing Churchill Butte bedrock, or matrix-supported, cobbly and pebbly debris-flow deposits of the Silver Springs fan. The lakeshore barrier spit is dominated by granule pebble gravel concentrated by wave erosion of the colluvial and alluvial-fan facies. The lakeward side of the barrier consists of beachface deposits of well-sorted granules or pebbles in broad, planar beds 1-10 cm thick and sloping 10-15°. They interfinger downslope with thicker (10-25 cm) and less steep (5-10°) lakeward-dipping beds of fine to medium pebble gravel of the lake upper shoreface. Interstratified with the latter are 10-40-cm-thick sets of high-angle cross-beds that dip southward, alongshore. Higher-angle (15-20°), landward-dipping foresets of similar texture but poorer sorting comprise the proximal backshore on the landward side of the barrier. They were deposited during storm surges that overtopped the barrier berm. Gastropod-rich sand and mud, also deposited by storm-induced washover, are found landward of the gravel foresets in a 15-m-wide backshore pond. Algal stromatolites, ostracodes, and diatoms accumulated in this pond between storm events. The lake lower shoreface, extending from water depths of 2 to 8 m, consists of a southward-prograding spit platform built by longshore drift. The key component of this platform is large-scale sandy pebble gravel in 16° southward-dipping `Gilbert' foresets that grade at a water depth of about 6-7 m to 4°-dipping sandy toesets. A shift from bioturbated lower-shoreface sand and silt, to flat and laminated lake-bottom silt and mud, occurs between water depths of 10-40 m and over a shore-normal distance of ≥250 m. This lake-bottom mud facies, unlike the others, is areally expansive.

Dancing droplets: Contact angle, drag, and confinement

NASA Astrophysics Data System (ADS)

Benusiglio, Adrien; Cira, Nate; Prakash, Manu

2015-11-01

When deposited on a clean glass slide, a mixture of water and propylene glycol forms a droplet of given contact angle, when both pure liquids spread. (Cira, Benusiglio, Prakash: Nature, 2015). The droplet is stabilized by a gradient of surface tension due to evaporation that induces a Marangoni flow from the border to the apex of the droplets. The apparent contact angle of the droplets depends on both their composition and the external humidity as captured by simple models. These droplets present remarkable properties such as lack of a large pinning force. We discuss the drag on these droplets as a function of various parameters. We show theoretical and experimental results of how various confinement geometries change the vapor gradient and the dynamics of droplet attraction.

Dust Erosion Performance of Candidate Motorcase Thermal Protection Materials.

DTIC Science & Technology

1980-03-10

Effects 21 3.1.2 Debris Shielding 22 3.1.3 Heating 22 3.1.3,1 Kinetic Energy Deposition 22 3.1.3.2 Convective Heating 24 3.1.4 Particle Velocity 32 3.1.5...29 13 Kinetic energy method comparison: 14-deg angle 3014 Kinetic energy method comparison: 30-deg angle 31 15 Convective heating in DET 32 16...Convective heating model comparison (po = 300 psi) 33 17 AEDC run 3 data trace 33 J. 18 Influence of surface temperature on erosion 35 V 19 Influence of

Controlled alignment of carbon nanofibers in a large-scale synthesis process

NASA Astrophysics Data System (ADS)

Merkulov, Vladimir I.; Melechko, A. V.; Guillorn, M. A.; Simpson, M. L.; Lowndes, D. H.; Whealton, J. H.; Raridon, R. J.

2002-06-01

Controlled alignment of catalytically grown carbon nanofibers (CNFs) at a variable angle to the substrate during a plasma-enhanced chemical vapor deposition process is achieved. The CNF alignment is controlled by the direction of the electric field lines during the synthesis process. Off normal CNF orientations are achieved by positioning the sample in the vicinity of geometrical features of the sample holder, where bending of the electric field lines occurs. The controlled growth of kinked CNFs that consist of two parts aligned at different angles to the substrate normal also is demonstrated.

Preliminary analyses of SIB-B radar data for recent Hawaii lava flows

NASA Technical Reports Server (NTRS)

Kaupp, V. H.; Derryberry, B. A.; Macdonald, H. C.; Gaddis, L. R.; Mouginis-Mark, P. J.

1986-01-01

The Shuttle Imaging Radar (SIR-B) experiment acquired two L-band (23 cm wavelength) radar images (at about 28 and 48 deg incidence angles) over the Kilauea Volcano area of southeastern Hawaii. Geologic analysis of these data indicates that, although aa lava flows and pyroclastic deposits can be discriminated, pahoehoe lava flows are not readily distinguished from surrounding low return materials. Preliminary analysis of data extracted from isolated flows indicates that flow type (i.e., aa or pahoehoe) and relative age can be determined from their basic statistics and illumination angle.

Structural changes of deposited casein micelles induced by membrane filtration.

PubMed

Gebhardt, R; Steinhauer, T; Meyer, P; Sterr, J; Perlich, J; Kulozik, U

2012-01-01

Casein micelles undergo shape changes when subjected to frontal filtration forces. Grazing incidence small angle X-ray scattering (GISAXS) and atomic force microscopy (AFM) allow a quantification of such structural changes on filtration cakes deposited on smooth silicon micro-sieves. A trans-membrane pressure of deltap = 400 mbar across the micro-sieve leads to an immediate film formation after deposition of casein solution. We observe significant changes in the GISAXS pattern depending on how many layers are stacked on top of each other. Compared to a deposit formed by one layer, GISAXS on a deposit formed by three layers of casein micelles leads to less scattering in the vertical and more scattering in the horizontal direction. Simulations show that the experimental results can be interpreted by a structural transformation from an originally spherical micelle shape to an ellipsoidal-deformed shape. The results are supported by AFM measurements showing a reduced lateral size of casein micelles deposited on top of a membrane pore. The observed shape changes could be due to filtration forces acting on densely packed deposits confining the micelles into ellipsoidal shapes.

Textural Evolution During Micro Direct Metal Deposition of NiTi Alloy

NASA Astrophysics Data System (ADS)

Khademzadeh, Saeed; Bariani, Paolo F.; Bruschi, Stefania

2018-03-01

In this research, a micro direct metal deposition process, newly developed as a potential method for micro additive manufacturing was used to fabricate NiTi builds. The effect of scanning strategy on grain growth and textural evolution was investigated using scanning electron microscope equipped with electron backscattered diffraction detector. Investigations showed that, the angle between the successive single tracks has an important role in grain size distribution and textural evolution of NiTi phase. Unidirectional laser beam scanning pattern developed a fiber texture; conversely, a backward and forward scanning pattern developed a strong < {100} > ‖‖ RD texture on the surface of NiTi cubic samples produced by micro direct metal deposition.

Textural Evolution During Micro Direct Metal Deposition of NiTi Alloy

NASA Astrophysics Data System (ADS)

Khademzadeh, Saeed; Bariani, Paolo F.; Bruschi, Stefania

2018-07-01

In this research, a micro direct metal deposition process, newly developed as a potential method for micro additive manufacturing was used to fabricate NiTi builds. The effect of scanning strategy on grain growth and textural evolution was investigated using scanning electron microscope equipped with electron backscattered diffraction detector. Investigations showed that, the angle between the successive single tracks has an important role in grain size distribution and textural evolution of NiTi phase. Unidirectional laser beam scanning pattern developed a fiber texture; conversely, a backward and forward scanning pattern developed a strong < {100} > ‖‖ RD texture on the surface of NiTi cubic samples produced by micro direct metal deposition.

Enhancing the platinum atomic layer deposition infiltration depth inside anodic alumina nanoporous membrane

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vaish, Amit, E-mail: anv@udel.edu; Krueger, Susan; Dimitriou, Michael

Nanoporous platinum membranes can be straightforwardly fabricated by forming a Pt coating inside the nanopores of anodic alumina membranes (AAO) using atomic layer deposition (ALD). However, the high-aspect-ratio of AAO makes Pt ALD very challenging. By tuning the process deposition temperature and precursor exposure time, enhanced infiltration depth along with conformal coating was achieved for Pt ALD inside the AAO templates. Cross-sectional scanning electron microscopy/energy dispersive x-ray spectroscopy and small angle neutron scattering were employed to analyze the Pt coverage and thickness inside the AAO nanopores. Additionally, one application of platinum-coated membrane was demonstrated by creating a high-density protein-functionalized interface.

Crystalline and magnetooptical characteristics of (Tb,Bi)3(Fe,Ga)5O12 deposited on (Y,Nd)3Al5O12

NASA Astrophysics Data System (ADS)

Morimoto, Ryohei; Goto, Taichi; Nakamura, Yuichi; Boey Lim, Pang; Uchida, Hironaga; Inoue, Mitsuteru

2018-06-01

We prepared Bi- and Ga-substituted Tb3Fe5O12 (BiGa:TIG) films on a Nd-substituted Y3Al5O12 (Nd:YAG) single crystal substrate by pulsed laser deposition, and investigated their magnetic, optical, and magnetooptical properties. A BiGa:TIG film deposited with a substrate temperature of 700 °C shows the easy axis of magnetization along the out-of-plane direction of the film and the Faraday rotation angle of 900°/cm at a wavelength of 1064 nm. The epitaxial growth of the film is confirmed by X-ray diffraction analysis.

Discontinuous contact line motion of evaporating particle-laden droplet on superhydrophobic surfaces

NASA Astrophysics Data System (ADS)

Yamada, Yutaka; Horibe, Akihiko

2018-04-01

The three-phase contact line motion on a superhydrophobic surface through particle-laden sessile droplet evaporation was investigated. Sample surfaces with micro- and nanoscale structures were generated by various durations of chemical treatment and Si O2 spherical particles with different sizes were used as additives of test liquid. The contact angle and contact radius profiles were studied, and the discontinuous motion of those profiles on micro- and nanostructured hierarchical surfaces was observed, while it was not observed on a nanostructured superhydrophobic surface. Suspensions with low particle concentration induced a relatively large contact radius jump compared to the high-concentrated condition; in contrast, the previous report showed the opposite trend for flat surfaces. In order to explain this result, a simple explanation was provided—that the stacked particles at the contact line region suppressed to the deformation of the liquid-vapor interface near the contact line. This is confirmed by side-view images of the deposition results because the contact line region after evaporation of the dense suspension showed a large contact angle compared to that of the diluted suspension. In addition, deposition at the contact line region was observed by scanning electron microscopy to discuss the effect of the characteristic length scale of the surface structure and particles on the contact line motion. We believe that these results will help one to understand the deposition phenomenon during particle-laden droplet evaporation on the superhydrophobic surface and its applications such as evaporation-driven materials deposition.

Ultrasensitive hydrogen sensor based on Pt-decorated WO₃ nanorods prepared by glancing-angle dc magnetron sputtering.

PubMed

Horprathum, M; Srichaiyaperk, T; Samransuksamer, B; Wisitsoraat, A; Eiamchai, P; Limwichean, S; Chananonnawathorn, C; Aiempanakit, K; Nuntawong, N; Patthanasettakul, V; Oros, C; Porntheeraphat, S; Songsiriritthigul, P; Nakajima, H; Tuantranont, A; Chindaudom, P

2014-12-24

In this work, we report an ultrasensitive hydrogen (H2) sensor based on tungsten trioxide (WO3) nanorods decorated with platinum (Pt) nanoparticles. WO3 nanorods were fabricated by dc magnetron sputtering with a glancing angle deposition (GLAD) technique, and decorations of Pt nanoparticles were performed by normal dc sputtering on WO3 nanorods with varying deposition time from 2.5 to 15 s. Crystal structures, morphologies, and chemical information on Pt-decorated WO3 nanorods were characterized by grazing-incident X-ray diffraction, field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, and photoelectron spectroscopy, respectively. The effect of the Pt nanoparticles on the H2-sensing performance of WO3 nanorods was investigated over a low concentration range of 150-3000 ppm of H2 at 150-350 °C working temperatures. The results showed that the H2 response greatly increased with increasing Pt-deposition time up to 10 s but then substantially deteriorated as the deposition time increased further. The optimally decorated Pt-WO3 nanorod sensor exhibited an ultrahigh H2 response from 1530 and 214,000 to 150 and 3000 ppm of H2, respectively, at 200 °C. The outstanding gas-sensing properties may be attributed to the excellent dispersion of fine Pt nanoparticles on WO3 nanorods having a very large effective surface area, leading to highly effective spillover of molecular hydrogen through Pt nanoparticles onto the WO3 nanorod surface.

Effects of thermal annealing on the structural, mechanical, and tribological properties of hard fluorinated carbon films deposited by plasma enhanced chemical vapor deposition

NASA Astrophysics Data System (ADS)

Maia da Costa, M. E. H.; Baumvol, I. J. R.; Radke, C.; Jacobsohn, L. G.; Zamora, R. R. M.; Freire, F. L.

2004-11-01

Hard amorphous fluorinated carbon films (a-C:F) deposited by plasma enhanced chemical vapor deposition were annealed in vacuum for 30 min in the temperature range of 200-600 °C. The structural and compositional modifications were followed by several analytical techniques: Rutherford backscattering spectrometry (RBS), elastic recoil detection analysis (ERDA), x-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. Nanoidentation measurements and lateral force microscopy experiments were carried out in order to provide the film hardness and the friction coefficient, respectively. The internal stress and contact angle were also measured. RBS, ERDA, and XPS results indicate that both fluorine and hydrogen losses occur for annealing temperatures higher than 300 °C. Raman spectroscopy shows a progressive graphitization upon annealing, while the surface became slightly more hydrophobic as revealed by the increase of the contact angle. Following the surface wettability reduction, a decrease of the friction coefficient was observed. These results highlight the influence of the capillary condensation on the nanoscale friction. The film hardness and the internal stress are constant up to 300 °C and decrease for higher annealing temperatures, showing a direct correlation with the atomic density of the films. Since the thickness variation is negligible, the mass loss upon thermal treatment results in amorphous structures with a lower degree of cross-linking, explaining the deterioration of the mechanical properties of the a-C:F films.

Age and Construction of Little Ambergris Cay Bedrock Rim, Southeastern Caicos Platform, British West Indies

NASA Astrophysics Data System (ADS)

Orzechowski, E. A.; Strauss, J. V.; Knoll, A. H.; Fischer, W. W.; Cantine, M.; Metcalfe, K.; Quinn, D. P.; Stein, N.; Gomes, M. L.; Grotzinger, H. M.; Lingappa, U.; O'Reilly, S. S.; Riedman, L. A.; Trower, L.; Grotzinger, J. P.

2016-12-01

The Caicos Platform's interior-platform ooid shoals and patch reef environments are unique modern examples of grain-rich carbonate settings. In July 2016, the Agouron Institute's Advanced Geobiology field course conducted a detailed study of Little Ambergris Cay, in the southeastern sector of the platform. The cay is fringed by a topographically high rim formed of amalgamated ridges of partially lithified fossiliferous grainstone and rudstone (i.e. beachrock conglomerate), that protects an interior basin dominated by microbial mats and mangroves. Tidal channels exchanging open platform waters with the interior basin breach the rim locally. We sampled and mapped the rim (using differential GPS) in order to examine its age, sedimentological characteristics, and faunal composition. Strata up to 2 meters above the present-day high tide mark form the rim, characterized by several carbonate lithofacies, including oolites with keystone vugs, high-angle trough cross bedding, seaward-dipping low angle stratification, bioturbation and fossiliferous lags, and rudstones composed of imbricated beachrock boulders. We interpret these facies as an upper shoreface to foreshore depositional setting dominated by local storm and eolian deposits. A distinct fossiliferous rudstone facies is dominated by mytilid bivalves, as well as Eustrombus, Conus, Oliva, and vermetid gastropods. X-ray powder diffraction analyses on fossil shells reveal both shells with pristine aragonite and shells with evidence of secondary calcite. Radiometric analyses of pristine aragonite material provide additional age constraints on these deposits. Understanding the formation of Little Ambergris Cay's bedrock deposits will provide important context for the island's geological history and geomorphology, aiding in our understanding of modern analogues for ancient interior platform depositional environments.

Fabrication of super-hydrophobic duo-structures

NASA Astrophysics Data System (ADS)

Zhang, X. Y.; Zhang, F.; Jiang, Y. J.; Wang, Y. Y.; Shi, Z. W.; Peng, C. S.

2015-04-01

Recently, super-hydrophobicity has attracted increasing attention due to its huge potential in the practical applications. In this paper, we have presented a duo-structure of the combination of micro-dot-matrix and nano-candle-soot. Polydimethylsiloxane (PDMS) was used as a combination layer between the dot-matrix and the soot particles. Firstly, a period of 9-μm dot-matrix was easily fabricated on the K9 glass using the most simple and mature photolithography process. Secondly, the dot-matrix surface was coated by a thin film of PDMS (elastomer: hardener=10:1) which was diluted by methylbenzene at the volume ratio of 1:8. Thirdly, we held the PDMS modified surface over a candle flame to deposit a soot layer and followed by a gentle water-risen to remove the non-adhered particles. At last, the samples were baked at 85°C for 2 hours and then the duo-structure surface with both micro-size dot-matrix and nano-size soot particles was obtained. The SEM indicated this novel surface morphology was quite like a lotus leaf of the well-know micro-nano-binary structures. As a result, the contact angle meter demonstrated such surface exhibited a perfect super-hydrophobicity with water contact angle of 153° and sliding angle of 3°. Besides, just listed as above, the fabrication process for our structure was quite more easy, smart and low-cost compared with the other production technique for super-hydrophobic surfaces such as the phase separation method, electrochemical deposition and chemical vapor deposition etc. Hence, this super-hydrophobic duo-structure reported in this letter was a great promising candidate for a wide and rapid commercialization in the future.

Scanning electron microscopy of the trabecular meshwork: understanding the pathogenesis of primary angle closure glaucoma.

PubMed

Sihota, Ramanjit; Goyal, Amita; Kaur, Jasbir; Gupta, Viney; Nag, Tapas C

2012-01-01

To study ultrastructural changes of the trabecular meshwork in acute and chronic primary angle closure glaucoma (PACG) and primary open angle glaucoma (POAG) eyes by scanning electron microscopy. Twenty-one trabecular meshwork surgical specimens from consecutive glaucomatous eyes after a trabeculectomy and five postmortem corneoscleral specimens were fixed immediately in Karnovsky solution. The tissues were washed in 0.1 M phosphate buffer saline, post-fixed in 1% osmium tetraoxide, dehydrated in acetone series (30-100%), dried and mounted. Normal trabecular tissue showed well-defined, thin, cylindrical uveal trabecular beams with many large spaces, overlying flatter corneoscleral beams and numerous smaller spaces. In acute PACG eyes, the trabecular meshwork showed grossly swollen, irregular trabecular endothelial cells with intercellular and occasional basal separation with few spaces. Numerous activated macrophages, leucocytes and amorphous debris were present. Chronic PACG eyes had a few, thickened posterior uveal trabecular beams visible. A homogenous deposit covered the anterior uveal trabeculae and spaces. Converging, fan-shaped trabecular beam configuration corresponded to gonioscopic areas of peripheral anterior synechiae. In POAG eyes, anterior uveal trabecular beams were thin and strap-like, while those posteriorly were wide, with a homogenous deposit covering and bridging intertrabecular spaces, especially posteriorly. Underlying corneoscleral trabecular layers and spaces were visualized in some areas. In acute PACG a marked edema of the endothelium probably contributes for the acute and marked intraocular pressure (IOP) elevation. Chronically raised IOP in chronic PACG and POAG probably results, at least in part, from decreased aqueous outflow secondary to widening and fusion of adjacent trabecular beams, together with the homogenous deposit enmeshing trabecular beams and spaces.

Properties of spray-deposited liquid-phase exfoliated graphene films

NASA Astrophysics Data System (ADS)

Sales, Maria Gabriela C.; Dela Vega, Ma. Shanlene D. C.; Vasquez, Magdaleno R., Jr.

2018-01-01

In this study, we demonstrate the feasibility of spray-depositing exfoliated graphene on flexible polyimide (PI) and rigid (soda lime glass) substrates for optoelectronic applications. The water contact angles of the substrates increased by 13% (for PI) and 49% (for glass) when the surfaces are pretreated with hexamethyldisiloxane, which significantly improved the adhesion of the films. Raman spectral analyses confirmed a minimum of 15 and a maximum of 23 layers of exfoliated graphene deposited on the substrates. After deposition, the films were exposed to 13.56 MHz radio-frequency plasma containing an admixture of argon and nitrogen gases. Plasma treatment modified the electrical properties with a response analogous to that of a rectifier. A 39% increase in transmittance in the visible region was also observed especially for glass substrates after plasma treatment without a significant change in film electrical conductivity.

Charge deposition dependence of electron transmission through PET nanocapillaries and a tapered glass microcapillary

NASA Astrophysics Data System (ADS)

Tanis, J. A.; Keerthisinghe, D.; Wickramarachchi, S. J.; Ikeda, T.; Stolterfoht, N.

2018-05-01

Charge deposition dependences of electron transmission through insulating PET nanocapillaries and a tapered glass microcapillary are reported and differences with HCI transmission are noted. Investigations were conducted for electrons with incident energies 500-1000 eV, corresponding to energies per charge similar to those used for HCI studies, incident on (1) an array of PET nanocapillaries (density ∼5 × 108/cm2) with diameters 100 nm in a foil of thickness 12 μm, and (2) on a tapered glass microcapillary with inlet/outlet diameters of 800/100 μm and a length of ∼35 mm. The transmission was measured for incident electrons at small sample tilt angles ranging from 0° to 5° with respect to the beam direction. For most angles, including those near zero degrees, there was an initial quiet period during which essentially no transmission was observed, followed by large rises in the transmission during relatively short periods of charge deposition before equilibrium of the transmission was reached. The resulting equilibrium was stable, blocked or had frequent oscillations depending on the incident energy and the capillary used. Observations for both capillaries show that a negative charge patch is needed to guide incident electrons through the capillaries similar to the manner in which HCIs are guided through capillaries.

Structural and optical properties of glancing angle deposited In2O3 columnar arrays and Si/In2O3 photodetector

NASA Astrophysics Data System (ADS)

Mondal, A.; Shougaijam, B.; Goswami, T.; Dhar, J. C.; Singh, N. K.; Choudhury, S.; Chattopadhay, K. K.

2014-04-01

Ordered and perpendicular columnar arrays of In2O3 were synthesized on conducting ITO electrode by a simple glancing angle deposition (GLAD) technique. The as-deposited In2O3 columns were investigated by field emission gun-scanning electron microscope (FEG-SEM). The average length and diameter of the columns were estimated ˜400 nm and ˜100 nm, respectively. The morphology of the structure was examined by transmission electron microscopy (TEM). X-ray diffraction (XRD) analysis shows the polycrystalline nature of the sample which was verified by selective area electron diffraction (SAED) analysis. The growth mechanism and optical properties of the columns were also discussed. Optical absorption shows that In2O3 columns have a high band to band transition at ˜3.75 eV. The ultraviolet and green emissions were obtained from the In2O3 columnar arrays. The P-N junction was formed between In2O3 and P-type Si substrate. The GLAD synthesized In2O3 film exhibits low current conduction compared to In2O3 TF. However, the Si/GLAD-In2O3 detector shows ˜1.5 times enhanced photoresponsivity than that of Si/In2O3 TF.

Creation of superhydrophobic stainless steel surfaces by acid treatments and hydrophobic film deposition.

PubMed

Li, Lester; Breedveld, Victor; Hess, Dennis W

2012-09-26

In this work, we present a method to render stainless steel surfaces superhydrophobic while maintaining their corrosion resistance. Creation of surface roughness on 304 and 316 grade stainless steels was performed using a hydrofluoric acid bath. New insight into the etch process is developed through a detailed analysis of the chemical and physical changes that occur on the stainless steel surfaces. As a result of intergranular corrosion, along with metallic oxide and fluoride redeposition, surface roughness was generated on the nano- and microscales. Differences in alloy composition between 304 and 316 grades of stainless steel led to variations in etch rate and different levels of surface roughness for similar etch times. After fluorocarbon film deposition to lower the surface energy, etched samples of 304 and 316 stainless steel displayed maximum static water contact angles of 159.9 and 146.6°, respectively. However, etching in HF also caused both grades of stainless steel to be susceptible to corrosion. By passivating the HF-etched samples in a nitric acid bath, the corrosion resistant properties of stainless steels were recovered. When a three step process was used, consisting of etching, passivation and fluorocarbon deposition, 304 and 316 stainless steel samples exhibited maximum contact angles of 157.3 and 134.9°, respectively, while maintaining corrosion resistance.

Geotechnical properties of ash deposits near Hilo, Hawaii

USGS Publications Warehouse

Wieczorek, G.F.; Jibson, R.W.; Wilson, R.C.; Buchanan-Banks, J. M.

1982-01-01

Two holes were hand augered and sampled in ash deposits near Hilo, Hawaii. Color, water content and sensitivity of the ash were measured in the field. The ash alternated between reddish brown and dark reddish brown in color and had water contents as high as 392%. A downhole vane shear device measured sensitivities as high as 6.9. A series of laboratory tests including grain size distribution, Atterberg limits, X-ray diffraction analysis, total carbon determination, vane shear, direct shear and triaxial tests were performed to determine the composition and geotechnical properties of the ash. The ash is very fine grained, highly plastic and composed mostly of gibbsite and amorphous material presumably allophane. The ash has a high angle of internal friction ranging from 40-43? and is classified as medium to very sensitive. A series of different ash layers was distinguished on the basis of plasticity and other geotechnical properties. Sensitivity may be due to a metastable fabric, cementation, leaching, high organic content, and thixotropy. The sensitivity of the volcanic ash deposits near Hilo is consistent with documented slope instability during earthquakes in Hawaii. The high angles of internal friction and cementation permit very steep slopes under static conditions. However, because of high sensitivity of the ash, these slopes are particularly susceptible to seismically-induced landsliding.

Applicability of ERTS-1 to Montana geology

NASA Technical Reports Server (NTRS)

Weidman, R. M. (Principal Investigator); Alt, D. D.; Berg, R. A.; Johns, W. M.; Flood, R. E.; Hawley, K. T.; Wackwitz, L. K.

1973-01-01

The author has identified the following significant results. A detailed band 7 ERTS-1 lineament map covering western Montana and northern Idaho has been prepared and is being evaluated by direct comparison with geologic maps, by statistical plots of lineaments and known faults, and by field checking. Lineament patterns apparent in the Idaho and Boulder batholiths do not correspond to any known geologic structures. A band 5 mosaic of Montana and adjacent areas has been laid and a lineament annotation prepared for comparison with the band 7 map. All work to date indicates that ERTS-1 imagery is very useful for revealing patterns of high-angle faults, though much less useful for mapping rock units and patterns of low-angle faults. Large-scale mosaics of U-2 photographs of three test sites have been prepared for annotation and comparison with ERTS-1 maps. Mapping of Quaternary deposits in the Glacial Lake Missoula basin using U-2 color infrared transparencies has been successful resulting in the discovery of some deposits not previously mapped. Detailed work has been done for Test Site 354 D using ERTS-1 imagery; criteria for recognition of several rock types have been found. Photogeologic mapping for southeastern Montana suggest Wasatch deposits where none shown of geologic map.

One-step solvothermal deposition of ZnO nanorod arrays on a wood surface for robust superamphiphobic performance and superior ultraviolet resistance

PubMed Central

Yao, Qiufang; Wang, Chao; Fan, Bitao; Wang, Hanwei; Sun, Qingfeng; Jin, Chunde; Zhang, Hong

2016-01-01

In the present paper, uniformly large-scale wurtzite-structured ZnO nanorod arrays (ZNAs) were deposited onto a wood surface through a one-step solvothermal method. The as-prepared samples were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetry (TG), and differential thermal analysis (DTA). ZNAs with a diameter of approximately 85 nm and a length of approximately 1.5 μm were chemically bonded onto the wood surface through hydrogen bonds. The superamphiphobic performance and ultraviolet resistance were measured and evaluated by water or oil contact angles (WCA or OCA) and roll-off angles, sand abrasion tests and an artificially accelerated ageing test. The results show that the ZNA-treated wood demonstrates a robust superamphiphobic performance under mechanical impact, corrosive liquids, intermittent and transpositional temperatures, and water spray. Additionally, the as-prepared wood sample shows superior ultraviolet resistance. PMID:27775091

ODS - modified TiO2 nanoparticles for the preparation of self-cleaning superhydrophobic coating

NASA Astrophysics Data System (ADS)

Kokare, Ashvini M.; Sutar, Rajaram S.; Deshmukh, S. G.; Xing, Ruimin; Liu, Shanhu; Latthe, Sanjay S.

2018-05-01

Rolling water drops takes off dust particles from lotus leaf showing self-cleaning performance. Self-cleaning effect has great importance in industry as well as in daily life. The present paper describes the preparation of self-cleaning superhydrophobic coating through simple and low cost dip coating technique. The prepared superhydrophobic surface enact as lotus leaf. Firstly TiO2 nanoparticles were dispersed in ethanol and different concentration of octadecyltrichlorosilane (ODS) was added in TiO2 dispersion. The effect of number of deposition layer on the wettability of the coating was studied. The coating prepared from five deposition layers showed contact angle higher than 150° and sliding angle less than 10°. The superhydrophobicity increases with increasing concentration of ODS. The hierarchical rough morphology which is preferable for superhydrophobicity was obtained. The prepared coatings were stable against water jet impact and showed repellent towards colored and muddy water. Such superhydrophobic coating can find enormous scope in self-cleaning application.

Surface structure analysis of BaSi2(100) epitaxial film grown on Si(111) using CAICISS

NASA Astrophysics Data System (ADS)

Okasaka, Shouta; Kubo, Osamu; Tamba, Daiki; Ohashi, Tomohiro; Tabata, Hiroshi; Katayama, Mitsuhiro

2015-05-01

Geometry and surface structure of a BaSi2(100) film on Si(111) formed by reactive deposition epitaxy (RDE) have been investigated using coaxial impact-collision ion scattering spectroscopy and atomic force microscopy. BaSi2(100) film can be grown only when the Ba deposition rate is sufficiently fast. It is revealed that a BaSi2(100) film grown at 600 °C has better crystallinity than a film grown at 750 °C owing to the mixture of planes other than (100) in the RDE process at higher temperatures. The azimuth angle dependence of the scattering intensity from Ba shows sixfold symmetry, indicating that the minimum height of surface steps on BaSi2(100) is half of the length of unit cell. By comparing the simulated azimuth angle dependences for more than ten surface models with experimental one, it is strongly indicated that the surface of a BaSi2(100) film grown on Si(111) is terminated by Si tetrahedra.

Resolution of ab initio shapes determined from small-angle scattering.

PubMed

Tuukkanen, Anne T; Kleywegt, Gerard J; Svergun, Dmitri I

2016-11-01

Spatial resolution is an important characteristic of structural models, and the authors of structures determined by X-ray crystallography or electron cryo-microscopy always provide the resolution upon publication and deposition. Small-angle scattering of X-rays or neutrons (SAS) has recently become a mainstream structural method providing the overall three-dimensional structures of proteins, nucleic acids and complexes in solution. However, no quantitative resolution measure is available for SAS-derived models, which significantly hampers their validation and further use. Here, a method is derived for resolution assessment for ab initio shape reconstruction from scattering data. The inherent variability of the ab initio shapes is utilized and it is demonstrated how their average Fourier shell correlation function is related to the model resolution. The method is validated against simulated data for proteins with known high-resolution structures and its efficiency is demonstrated in applications to experimental data. It is proposed that henceforth the resolution be reported in publications and depositions of ab initio SAS models.

Resolution of ab initio shapes determined from small-angle scattering

PubMed Central

Tuukkanen, Anne T.; Kleywegt, Gerard J.; Svergun, Dmitri I.

2016-01-01

Spatial resolution is an important characteristic of structural models, and the authors of structures determined by X-ray crystallography or electron cryo-microscopy always provide the resolution upon publication and deposition. Small-angle scattering of X-rays or neutrons (SAS) has recently become a mainstream structural method providing the overall three-dimensional structures of proteins, nucleic acids and complexes in solution. However, no quantitative resolution measure is available for SAS-derived models, which significantly hampers their validation and further use. Here, a method is derived for resolution assessment for ab initio shape reconstruction from scattering data. The inherent variability of the ab initio shapes is utilized and it is demonstrated how their average Fourier shell correlation function is related to the model resolution. The method is validated against simulated data for proteins with known high-resolution structures and its efficiency is demonstrated in applications to experimental data. It is proposed that henceforth the resolution be reported in publications and depositions of ab initio SAS models. PMID:27840683

One-step solvothermal deposition of ZnO nanorod arrays on a wood surface for robust superamphiphobic performance and superior ultraviolet resistance

NASA Astrophysics Data System (ADS)

Yao, Qiufang; Wang, Chao; Fan, Bitao; Wang, Hanwei; Sun, Qingfeng; Jin, Chunde; Zhang, Hong

2016-10-01

In the present paper, uniformly large-scale wurtzite-structured ZnO nanorod arrays (ZNAs) were deposited onto a wood surface through a one-step solvothermal method. The as-prepared samples were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetry (TG), and differential thermal analysis (DTA). ZNAs with a diameter of approximately 85 nm and a length of approximately 1.5 μm were chemically bonded onto the wood surface through hydrogen bonds. The superamphiphobic performance and ultraviolet resistance were measured and evaluated by water or oil contact angles (WCA or OCA) and roll-off angles, sand abrasion tests and an artificially accelerated ageing test. The results show that the ZNA-treated wood demonstrates a robust superamphiphobic performance under mechanical impact, corrosive liquids, intermittent and transpositional temperatures, and water spray. Additionally, the as-prepared wood sample shows superior ultraviolet resistance.

Advances in silicon carbide Chemical Vapor Deposition (CVD) for semiconductor device fabrication

NASA Technical Reports Server (NTRS)

Powell, J. Anthony; Petit, Jeremy B.; Matus, Lawrence G.

1991-01-01

Improved SiC chemical vapor deposition films of both 3C and 6H polytypes were grown on vicinal (0001) 6H-SiC wafers cut from single-crystal boules. These films were produced from silane and propane in hydrogen at one atmosphere at a temperature of 1725 K. Among the more important factors which affected the structure and morphology of the grown films were the tilt angle of the substrate, the polarity of the growth surface, and the pregrowth surface treatment of the substrate. With proper pregrowth surface treatment, 6H films were grown on 6H substrates with tilt angles as small as 0.1 degrees. In addition, 3C could be induced to grow within selected regions on a 6H substrate. The polarity of the substrate was a large factor in the incorporation of dopants during epitaxial growth. A new growth model is discussed which explains the control of SiC polytype in epitaxial growth on vicinal (0001) SiC substrates.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dave, V., E-mail: vdaditya1000@gmail.com; Rao, G. P., E-mail: ragrao38@gmail.com; Tiwari, G. S., E-mail: tiwarigsin@yahoo.com

Cultivator, one of the agriculture farm tool, extensively suffers from the wear problem. In this paper, we report nanostructured chromium nitrite (CrN) coating for the cultivator shovels to mitigate wear problem. The (CrN) coating was developed using DC magnetron sputtering technique at 200 °C. The structural, morphological, hydrophobic and wear properties were investigated using X-ray diffractometer, scanning electron microscope, contact angle goniometer and custom designed soil bin assembly. The XRD reveals that the deposited coating was polycrystalline in nature with cubic structure. Also, The deposited coating was found to be anti wear resistant as well as hydrophobic in nature. Themore » gravimetric wear for the coating developed at 200 °C coated was found out to be 8.15 gm and for non coated it was 14.48 gm tested for 100 hrs. The roughness of the coating plays an important role in determining the hydrophobicity of the coated film. Roughness and contact angle measured for 200 °C coated shovel was found out to be 11.17 nm and 105 ° respectively.« less

Ultralow refractive index optical films with enhanced mechanical performance obtained by hybrid glancing angle deposition.

PubMed

Trottier-Lapointe, W; Zabeida, O; Schmitt, T; Martinu, L

2016-11-01

Ultralow refractive index materials (n less than 1.38 at 550 nm) are of particular interest in the context of antireflective coatings, allowing one to enhance their overall optical performance. However, application of such materials is typically limited by their mechanical properties. In this study, we explore the characteristics of a new category of hybrid (organic/inorganic) SiOCH thin films prepared by glancing angle deposition (GLAD) using electron beam evaporation of SiO₂ in the presence of an organosilicon precursor. The resulting layers exhibited n as low as 1.2, showed high elastic rebound, and generally better mechanical properties than their inorganic counterparts. In addition, hybrid GLAD films were found to be highly hydrophobic. The performance of the films is discussed in terms of their hybridicity (organic/inorganic) ratio determined by infrared spectroscopic ellipsometry as well as the presence of anisotropy assessed by the nanostructure-based spectroscopic ellipsometry model. Finally, we demonstrate successful implementation of the ultralow-index material in a complete antireflective stack.

Piezoresistive effect observed in flexible amorphous carbon films

NASA Astrophysics Data System (ADS)

Wang, B.; Jiang, Y. C.; Zhao, R.; Liu, G. Z.; He, A. P.; Gao, J.

2018-05-01

Amorphous carbon (a-C) films, deposited on Si substrates at 500 °C, were transferred onto flexible polyethylene (PE) substrates by a lift-off method, which overcomes the limit of deposition temperature. After transferring, a-C films exhibited a large piezoresistive effect. Such flexible samples could detect the change of bending angle by attaching them onto Cu foils. The ratio of the bending and non-bending resistances reaches as large as ~27.8, which indicates a potential application as a pressure sensor. Also, the a-C/PE sample revealed an enhanced sensitivity to gas pressure compared with the a-C/Si one. By controlling the bending angle, the sensitivity range can be tuned to shift to a low- or high-pressure region. The fatigue test shows a less than 1% change in resistance after 10 000 bending cycles. Our work provides a route to prepare the flexible and piezoresistive carbon-based devices with high sensitivity, controllable pressure-sensing and high stability.

Dependence of anti-Stokes/Stokes intensity ratios on substrate optical properties for Brillouin light scattering from ultrathin iron films

NASA Astrophysics Data System (ADS)

Cochran, J. F.; From, M.; Heinrich, B.

1998-06-01

Brillouin light scattering experiments have been used to investigate the intensity of 5145 Å laser light backscattered from spin waves in 20 monolayer thick Fe(001) films. The experiments have shown that the ratio of frequency upshifted light intensity to frequency downshifted light intensity depends upon the material of the substrate used to support the iron films. For a fixed magnetic field and for a fixed angle of incidence of the laser light this intensity ratio is much larger for an iron film deposited on a sulphur passivated GaAs(001) substrate than for an iron film deposited on a Ag(001) substrate. The data have been compared with a calculation that takes into account multiple scattering of the optical waves in the iron film and in a protective gold overlayer. The observations are in qualitative agreement with the theory, except for angles of incidence greater than 60°.

Magnetic anisotropy at material interfaces

NASA Astrophysics Data System (ADS)

Greene, Peter Kevin

In this dissertation, a comprehensive set of depth dependent magnetic measurements, as well as structural characterizations, were carried out on the Co/Pd multilayer system. The first-order reversal curve (FORC) technique is applied extensively to identify reversal mechanisms and different reversal phases within the material. In particular, the extension of the FORC technique to x-ray magnetic circular dichroism (XMCD) as a surface sensitive technique that identifies reversible magnetization change was performed for the first time. Polarized neutron reflectivity (PNR) was also used to directly measure the magnetization as a function of depth. The effects of deposition pressure grading within the Co/Pd multilayers were investigated. Structures were graded with three distinct pressure regions. FORC analysis shows that not only does increasing the deposition pressure increase the coercivity and effective anisotropy within that region, but also the order in which the pressure is changed also affects the entire structure. Layers grown at high sputtering pressures tend to reverse via domain wall pinning and rotation while those grown at lower pressures reverse via rapid domain wall propagation laterally across the film. Having high pressure layers underneath low pressure layers causes disorder to vertically propagate and lessen the induced anisotropy gradient. This analysis is confirmed by depth dependent magnetization profiles obtain from PNR. Continuously pressure-graded Co/Pd multilayers were then sputtered at two incident angles onto porous aluminum oxide templates with different pore aspect ratios. The effects of pressure grading versus uniform low pressure deposition is studied, as well as the effect of the angle of the incident deposition flux. The coercivity of the pressure graded perpendicular flux sample is compared to the low pressure sample. Additionally the effect of deposition angle and pore sidewall deposition is investigated. It is shown that sidewall deposition strongly affects the reversal behavior. As another way to induce a vertical anisotropy gradient, Co/Pd multilayers were bombarded with Ar+ ions at different energies and fluences. The effects of the depth dependent structural damage as a function of irradiation conditions were investigated. It is shown that the structural damage weakens the perpendicular anisotropy of the surface layers, causing a tilting of the surface magnetic moment into the plane of the film. The surface behavior is explicitly measured and shown to have a significant tilting angle in the top 5 nm depending on irradiation energy and fluence. Continuing the study of vertical anisotropy gradients in Co/Pd multilayers, multilayers with varied Co thickness were studied. Four films with varying Co thickness profiles were created and then patterned into nanodot arrays with diameters between 700 nm and 70 nm. The different films were graded continuously, or in stacks with varying Co thicknesses. An anisotropy gradient is shown to be established in the graded samples, and the switching field is lowered as a result. Furthermore, in the continuously graded samples the magnetization reversal behavior is fundamentally different from all other samples. The thermal energy barriers are measured in the uniform and continuously graded samples, yielding similar results. Finally, the establishment of exchange anisotropy at the ferromagnet / antiferromagnet (FM/AFM) interface in the epitaxial Fe/CoO system is investigated as a function of AFM thickness. The establishment of frozen AFM moments is analyzed using the FORC technique. The FORC technique combined with vector coil measurements also shows the transition from rotatable AFM to pinned AFM moments and suggests a mechanism of winding domain walls within the bulk AFM. (Abstract shortened by UMI.).

Post-glacial rock avalanches in the Obersee Valley, Glarner Alps, Switzerland

NASA Astrophysics Data System (ADS)

Nagelisen, Jan; Moore, Jeffrey R.; Vockenhuber, Christoph; Ivy-Ochs, Susan

2015-06-01

The geological record of prehistoric rock avalanches provides invaluable data for assessing the hazard posed by these rare but destructive mass movements. Here we investigate two large rock avalanches in the Obersee valley of the Glarner Alps, Switzerland, providing detailed mapping of landslide and related Quaternary phenomena, revised volume estimates for each event, and surface exposure dating of rock avalanche deposits. The Rautispitz rock avalanche originated from the southern flank of the Obersee valley, releasing approximately 91 million m3 of limestone on steeply-dipping bedding planes. Debris had maximum horizontal travel distance of ~ 5000 m, a fahrboeschung angle (relating fall height to length) of 18°, and was responsible for the creation of Lake Obersee; deposits are more than 130 m thick in places. The Platten rock avalanche encompassed a source volume of 11 million m3 sliding from the northern flank of the Obersee valley on similar steeply-dipping limestone beds (bedrock forms a syncline under the valley). Debris had a maximum horizontal travel distance of 1600 m with a fahrboeschung angle of 21°, and is more than 80 m thick in places. Deposits of the Platten rock avalanche are superposed atop those from the Rautispitz event at the end of the Obersee valley where they dam Lake Haslensee. Runout for both events was simulated using the dynamic analysis code DAN3D; results showed excellent match to mapped deposit extents and thickness and helped confirm the hypothesized single-event failure scenarios. 36Cl cosmogenic nuclide surface exposure dating of 13 deposited boulders revealed a Younger Dryas age of 12.6 ± 1.0 ka for the Rautispitz rock avalanche and a mid-Holocene age of 6.1 ± 0.8 ka for the Platten rock avalanche. A seismological trigger is proposed for the former event due to potentially correlated turbidite deposits in nearby Lake Zurich.

Development Programs and Activities for Southeast Asia Regional Office of Astronomy for Development

NASA Astrophysics Data System (ADS)

Insiri, Wichan

2015-08-01

In recent years, since the establishment of SEA-ROAD in 2012, the office has seen an exponential progress as it has proved to be one of the prominent regional hubs for IAU-OAD. Recent activities over the past years ranging from Winter and Summer Schools Trainings to Astronomy Technology Transfer Camp for high school students to Internship at NARIT are some examples of what promises to be a good sign of progressive leap in astronomy for the entire region. SEA-ROAD will continue to make an impact on astronomy education, popularization and public outreach as the office is vital and imperative to the capacity building of astronomy of the entire region.

Influence of Layer Thickness and Raster Angle on the Mechanical Properties of 3D-Printed PEEK and a Comparative Mechanical Study between PEEK and ABS.

PubMed

Wu, Wenzheng; Geng, Peng; Li, Guiwei; Zhao, Di; Zhang, Haibo; Zhao, Ji

2015-09-01

Fused deposition modeling (FDM) is a rapidly growing 3D printing technology. However, printing materials are restricted to acrylonitrile butadiene styrene (ABS) or poly (lactic acid) (PLA) in most Fused deposition modeling (FDM) equipment. Here, we report on a new high-performance printing material, polyether-ether-ketone (PEEK), which could surmount these shortcomings. This paper is devoted to studying the influence of layer thickness and raster angle on the mechanical properties of 3D-printed PEEK. Samples with three different layer thicknesses (200, 300 and 400 μm) and raster angles (0°, 30° and 45°) were built using a polyether-ether-ketone (PEEK) 3D printing system and their tensile, compressive and bending strengths were tested. The optimal mechanical properties of polyether-ether-ketone (PEEK) samples were found at a layer thickness of 300 μm and a raster angle of 0°. To evaluate the printing performance of polyether-ether-ketone (PEEK) samples, a comparison was made between the mechanical properties of 3D-printed polyether-ether-ketone (PEEK) and acrylonitrile butadiene styrene (ABS) parts. The results suggest that the average tensile strengths of polyether-ether-ketone (PEEK) parts were 108% higher than those for acrylonitrile butadiene styrene (ABS), and compressive strengths were 114% and bending strengths were 115%. However, the modulus of elasticity for both materials was similar. These results indicate that the mechanical properties of 3D-printed polyether-ether-ketone (PEEK) are superior to 3D-printed ABS.

Influence of Layer Thickness and Raster Angle on the Mechanical Properties of 3D-Printed PEEK and a Comparative Mechanical Study between PEEK and ABS

PubMed Central

Wu, Wenzheng; Geng, Peng; Li, Guiwei; Zhao, Di; Zhang, Haibo; Zhao, Ji

2015-01-01

Fused deposition modeling (FDM) is a rapidly growing 3D printing technology. However, printing materials are restricted to acrylonitrile butadiene styrene (ABS) or poly (lactic acid) (PLA) in most Fused deposition modeling (FDM) equipment. Here, we report on a new high-performance printing material, polyether-ether-ketone (PEEK), which could surmount these shortcomings. This paper is devoted to studying the influence of layer thickness and raster angle on the mechanical properties of 3D-printed PEEK. Samples with three different layer thicknesses (200, 300 and 400 μm) and raster angles (0°, 30° and 45°) were built using a polyether-ether-ketone (PEEK) 3D printing system and their tensile, compressive and bending strengths were tested. The optimal mechanical properties of polyether-ether-ketone (PEEK) samples were found at a layer thickness of 300 μm and a raster angle of 0°. To evaluate the printing performance of polyether-ether-ketone (PEEK) samples, a comparison was made between the mechanical properties of 3D-printed polyether-ether-ketone (PEEK) and acrylonitrile butadiene styrene (ABS) parts. The results suggest that the average tensile strengths of polyether-ether-ketone (PEEK) parts were 108% higher than those for acrylonitrile butadiene styrene (ABS), and compressive strengths were 114% and bending strengths were 115%. However, the modulus of elasticity for both materials was similar. These results indicate that the mechanical properties of 3D-printed polyether-ether-ketone (PEEK) are superior to 3D-printed ABS. PMID:28793537

Nature and distribution of surficial deposits in Chryse Planitia and vicinity, Mars

NASA Technical Reports Server (NTRS)

Arvidson, Raymond E.; Guinness, Edward A.; Dale-Bannister, Mary A.; Adams, John; Smith, Milton

1989-01-01

The properties and lateral distribution of surficial units for the Mutch Memorial Station region are examined, using color images of the dust deposits in the region obtained at variable incidence angles during sol 611. The radiance factors from the region are compared with values derived from Viking Orbiter images and the materials in and around the region are described. Viking, earth-based, and laboratory spectra are compared and a model is constructed for the nature and distribution of surficial units in the Chryse Planitia region.

Development of Novel Magnetic Metal Oxide Thin Films and Carbon Nanotube Materials for Potential Device Applications

DTIC Science & Technology

2016-05-09

9 3 Fe/MWCNTs/ SiO2 and Nano...magnetization measurements -1.5 0.0 1.5 To rq ue (a .u .) IP H = 1.9 T CoFe2 on glass in-Field -1.5 0.0 1.5 To rq ue (a . u .) 360300240180120600 Field Angle...deg.) IP H = 1.9 T CoFe2 on glass no-Field a b Fig. 2.3: Torque magnetometry for CoFe2 layer deposited (a) in-field and (b) deposited with no

Artificial in-plane ordering of textured YBa2Cu3O(7-x) films deposited on polycrystalline yttria-stabilized zirconia substrates

NASA Astrophysics Data System (ADS)

Harshavardhan, K. S.; Rajeswari, M.; Hwang, D. M.; Chen, C. Y.; Sands, T. D.; Venkatesan, T.; Tkaczyk, J. E.; Lay, K. W.; Safari, A.; Johnson, L.

1992-12-01

Anisotropic surface texturing of the polycrystalline yttria-stabilized zirconia substrates, prior to YBa2Cu3O(7-x) film deposition, is shown to promote in-plane (basal plane) ordering of the film growth in addition to the c-axis texturing. The Jc's of the films in the weak-link-dominated low-field regime are enhanced considerably, and this result is attributed to the reduction of weak links resulting from a reduction in the number of in-plane large-angle grain boundaries.

Transmission of low-energy negative ions through insulating nanocapillaries

NASA Astrophysics Data System (ADS)

Zhang, Qi; Liu, Zhonglin; Li, Pengfei; Jin, Bo; Song, Guangyin; Jin, Dingkun; Niu, Ben; Wei, Long; Ha, Shuai; Xie, Yiming; Ma, Yue; Wan, Chengliang; Cui, Ying; Zhou, Peng; Zhang, Hongqiang; Chen, Ximeng

2018-04-01

A simulation is performed to study the transmission of low-energy C l- ions through A l2O3 nanocapillaries. For the trajectory simulations, there are several processes involved: the image forces induced by the projectile; the electrostatic force from the deposited charges; the scattering from the inner surface and charge exchange. The simulation reproduces the main features of the experiments; i.e., the double peak structure in the transmitted angular distribution and the transmitted fractions of C l- , C l+ , and C l0 were found in the charge state distribution. The transmitted C l- ions are centered around the beam direction while the transmitted fractions of C l0 and C l+ are centered around the tilt angles. The role of the deposited charge is also studied by simulations. With the deposited charge, it is found that C l- is dominant in the transmission and the majority of the ions, centered around the tilt angle, are mainly from the single deflection by the negative charge patches on the inner surfaces of the capillaries, and only a few directly transmitted C l- ions are centered around the incident direction. There are also a few transmitted fractions of C l0 and C l+ from close surface scatterings. In the case that there are no negative charge patches, the simulation agrees with the experiment in detail: The majority of the directly transmitted C l- ions are centered around the incident direction while only a few scattered C l- ions are centered around the tilt angle from the single close collisions with the inner surfaces of the capillaries. There is a portion, comparable to the transmitted fraction of C l- , of the transmitted fractions of C l0 and C l+ , centered around the tilt angle, from the single scatterings with the inner surfaces of the capillaries. This confirms that at the present experimental conditions there are most probably no negative charge patches formed to guide the negative ions through insulating A l2O3 nanocapillaries.

Preparation and properties of ZnS superhydrophobic surface with hierarchical structure

NASA Astrophysics Data System (ADS)

Yao, Lujun; Zheng, Maojun; He, Shuanghu; Ma, Li; Li, Mei; Shen, Wenzhong

2011-01-01

A novel ZnS hierarchical structure composed of nanorod arrays with branched nanosheets and nanowires grown on their upside walls, was synthesized over Au-coated silicon substrate via chemical vapor deposition technique. Contact angle and sliding angle of this hierarchical film with no surface modification were measured to be about 153.8° and 9.1° for 5 μl water droplets. Self-cleaning behavior and dynamic water-repelling performance were clearly demonstrated. In addition, electrowetting transition phenomenon from superhydrophobic to hydrophilic state happened when a critical bias ∼7.0 V was applied. Below this threshold voltage, the contact angle change is little. This work for the first time reports the creation of ZnS superhydrophobic surface and could enrich its research field as surface functional materials.

Portable mini-chamber for temperature dependent studies using small angle and wide angle x-ray scattering

NASA Astrophysics Data System (ADS)

Dev, Arun Singh; Kumar, Dileep; Potdar, Satish; Pandit, Pallavi; Roth, Stephan V.; Gupta, Ajay

2018-04-01

The present work describes the design and performance of a vacuum compatible portable mini chamber for temperature dependent GISAXS and GIWAXS studies of thin films and multilayer structures. The water cooled body of the chamber allows sample annealing up to 900 K using ultra high vacuum compatible (UHV) pyrolytic boron nitride heater, thus making it possible to study the temperature dependent evolution of structure and morphology of two-dimensional nanostructured materials. Due to its light weight and small size, the chamber is portable and can be accommodated at synchrotron facilities worldwide. A systematic illustration of the versatility of the chamber has been demonstrated at beamline P03, PETRA-III, DESY, Hamburg, Germany. Temperature dependent grazing incidence small angle x-ray scattering (GISAXS) and grazing incidence wide angle x-ray scattering (GIWAXS) measurements were performed on oblique angle deposited Co/Ag multilayer structure, which jointly revealed that the surface diffusion in Co columns in Co/Ag multilayer enhances by increasing temperature from RT to ˜573 K. This results in a morphology change from columnar tilted structure to densely packed morphological isotropic multilayer.

Methods for making deposited films with improved microstructures

DOEpatents

Patten, James W.; Moss, Ronald W.; McClanahan, Edwin D.

1982-01-01

Methods for improving microstructures of line-of-sight deposited films are described. Columnar growth defects ordinarily produced by geometrical shadowing during deposition of such films are eliminated without resorting to post-deposition thermal or mechanical treatments. The native, as-deposited coating qualities, including homogeneity, fine grain size, and high coating-to-substrate adherence, can thus be retained. The preferred method includes the steps of emitting material from a source toward a substrate to deposit a coating non-uniformly on the substrate surface, removing a portion of the coating uniformly over the surface, again depositing material onto the surface, but from a different direction, and repeating the foregoing steps. The quality of line-of-sight deposited films such as those produced by sputtering, progressively deteriorates as the angle of incidence between the flux and the surface becomes increasingly acute. Depositing non-uniformly, so that the coating becomes progressively thinner as quality deteriorates, followed by uniformly removing some of the coating, such as by resputtering, eliminates the poor quality portions, leaving only high quality portions of the coating. Subsequently sputtering from a different direction applies a high quality coating to other regions of the surface. Such steps can be performed either simultaneously or sequentially to apply coatings of a uniformly high quality, closed microstructure to three-dimensional or larger planar surfaces.

Deposited films with improved microstructures

DOEpatents

Patten, James W.; Moss, Ronald W.; McClanahan, Edwin D.

1984-01-01

Methods for improving microstructures of line-of-sight deposited films are described. Columnar growth defects ordinarily produced by geometrical shadowing during deposition of such films are eliminated without resorting to post-deposition thermal or mechanical treatments. The native, as-deposited coating qualities, including homogeneity, fine grain size, and high coating-to-substrate adherence, can thus be retained. The preferred method includes the steps of emitting material from a source toward a substrate to deposit a coating non-uniformly on the substrate surface, removing a portion of the coating uniformly over the surface, again depositing material onto the surface, but from a different direction, and repeating the foregoing steps. The quality of line-of-sight deposited films such as those produced by sputtering, progressively deteriorates as the angle of incidence between the flux and the surface becomes increasingly acute. Depositing non-uniformly, so that the coating becomes progressively thinner as quality deteriorates, followed by uniformly removing some of the coating, such as by resputtering, eliminates the poor quality portions, leaving only high quality portions of the coating. Subsequently sputtering from a different direction applies a high quality coating to other regions of the surface. Such steps can be performed either simultaneously or sequentially to apply coatings of a uniformly high quality, closed microstructure to three-dimensional or large planar surfaces.

The deposition of gold nanoparticles in MWCNT forests

NASA Astrophysics Data System (ADS)

de Jong, Franciscus; Buffet, Adeline; Schlueter, Michael

2015-11-01

The deposition, i.e. transport and attachment, of small-sized particles is a basic process, on which many applications are based. The innumerable applications range from biology and medicine to engineering. Due to their promising mechanical properties multi-walled carbon nanotubes (MWCNTs) have gained increasing popularity in the past decade. A large number of dense packed vertically aligned MWCNTs form a so-called MWCNT forest. In our study we functionalized the MWCNT forest to filter gold nanoparticles from a colloidal suspension. An experimental investigation was carried out in which the particle deposition kinetics was locally determined with small-angle X-ray scattering (SAXS). Furthermore, inductively coupled plasma atomic emission spectroscopy (ICP-AES) was used to verify the local observations. It was concluded that both, SAXS and ICP-AES investigations shows very good agreement. Furthermore, an analytical deposition model was developed based on the DLVO-theory. The experimental and theoretical investigation presented here give insight in the deposition kinetics within a MWCNT forest. The results open up pathways to optimize MWCNT forests for filtering purposes.

Quantification of metallic nanoparticle morphology with tilt series imaging by transmission electron microscopy

NASA Astrophysics Data System (ADS)

Dutta, Aniruddha; Yuan, Biao; Clukay, Christopher J.; Grabill, Christopher N.; Heinrich, Helge; Bhattacharya, Aniket; Kuebler, Stephen M.

2012-02-01

We report on the quantitative analysis of electrolessly deposited Au and Ag nanoparticles (NPs) on SU8 polymer with the help of High-Angle Annular Dark-Field Scanning Transmission Electron Microscopy (HAADF-STEM) in tilt series. Au NPs act as nucleating agents for the electroless deposition of silver. Au NPs were prepared by attachingAu^3+cations to amine functionalized SU8 polymeric surfaces and then reducing it with aqueous NaBH4. The nanoscale morphology of the deposited NPs on the surface of polymer has been studied from the dark field TEM cross sectional images. Ag NPs were deposited on the cross-linked polymeric surface from a silver citrate solution reduced by hydroquinone. HAADF-STEM enables us to determine the distances between the NPs and their exact locations at and near the surface. The particle distribution, sizes and densities provide us with the data necessary to control the parameters for the development of the electroless deposition technique for emerging nanoscale technologies.

Design of Inorganic Water Repellent Coatings for Thermal Protection Insulation on an Aerospace Vehicle

NASA Technical Reports Server (NTRS)

Fuerstenau, D. W.; Ravikumar, R.

1997-01-01

In this report, thin film deposition of one of the model candidate materials for use as water repellent coating on the thermal protection systems (TPS) of an aerospace vehicle was investigated. The material tested was boron nitride (BN), the water-repellent properties of which was detailed in our other investigation. Two different methods, chemical vapor deposition (CVD) and pulsed laser deposition (PLD), were used to prepare the BN films on a fused quartz substrate (one of the components of thermal protection systems on aerospace vehicles). The deposited films were characterized by a variety of techniques including X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electron microscopy. The BN films were observed to be amorphous in nature, and a CVD-deposited film yielded a contact angle of 60 degrees with water, similar to the pellet BN samples investigated previously. This demonstrates that it is possible to use the bulk sample wetting properties as a guideline to determine the candidate waterproofing material for the TPS.

A theory of growing crystalline nanorods - Mode I

NASA Astrophysics Data System (ADS)

Du, Feng; Huang, Hanchen

2018-08-01

Nanorods grow in two possible modes during physical vapor deposition (PVD). In mode I, monolayer surface steps dictate the diameter of nanorods. In mode II, multiple-layer surface steps dictate the diameter, which is the smallest possible under physical vapor deposition [5,10]. This paper reports closed-form theories of terrace lengths and nanorod diameter during the growth in mode I, as a function of deposition conditions. The accompanying lattice kinetic Monte Carlo simulations verify these theories. This study reveals that (1) quasi-steady growth exists for each set of nanorod growth conditions, and (2) the characteristic length scales, including terrace lengths and nanorod diameter at the quasi-steady state, depend on the deposition conditions - deposition rate F, substrate temperature T, and incidence angle θ - only as a function of l2D/tan θ, with l2 D = 2(v2 D/Fcosθ) 1/3 as a diffusion-limited length scale and v2D as the atomic diffusion jump rate over monolayer surface steps.

Geologic map of the Topock 7.5’ quadrangle, Arizona and California

USGS Publications Warehouse

Howard, Keith A.; John, Barbara E.; Nielson, Jane E.; Miller, Julia M.G.; Wooden, Joseph L.

2013-01-01

The Topock quadrangle exposes a structurally complex part of the Colorado River extensional corridor and also exposes deposits that record landscape evolution during the history of the Colorado River. Paleoproterozoic gneisses and Mesoproterozoic granitoids and intrusive sheets are exposed through tilted cross-sectional thicknesses of many kilometers. Intruding them are a series of Mesozoic to Tertiary igneous rocks including dismembered parts of the Late Cretaceous Chemehuevi Mountains Plutonic Suite. Plutons of this suite in Arizona, if structurally restored for Miocene extension, formed cupolas capping the Chemehuevi Mountains batholith in California. Thick (1–3 km) Miocene sections of volcanic rocks, sedimentary breccias, conglomerate, and sandstone rest nonconformably on the Proterozoic rocks and record the structural and depositional evolution of the Colorado River extensional corridor. Four major Miocene low-angle normal faults and a steep block-bounding fault that developed during this episode divide the deformed rocks of the quadrangle into major structural plates and tilted blocks in and east of the Chemehuevi Mountains core complex. The low-angle faults attenuate crustal section, superposing supracrustal and upper crustal rocks against gneisses and granitoids originally from deeper crustal levels. The transverse block-bounding Gold Dome Fault Zone juxtaposes two large hanging-wall blocks, each tilted 90°, and the fault zone splays at its tip into folds in layered Miocene rocks. A synfaulting intrusion occupies the triangular zone where the folded strata detached from an inside corner along this fault between the tilt blocks. Post-extensional upper Miocene to Quaternary strata, locally deformed, record post-extensional landscape evolution, including several Pliocene and younger aggradational episodes in the Colorado River valley and intervening degradation episodes. The aggradational sequences include (1) the Bouse Formation, (2) fluvial deposits correlated with the alluvium of Bullhead City, (3) the younger fluvial boulder conglomerate of Bat Cave Wash, (4) the fluvial Chemehuevi Formation and related valley-margin deposits, and (5) fluvial Holocene deposits under the river and the valley floor. These fluvial records of Colorado River deposition are interspersed with piedmont alluvial fan deposits of several ages.

Effects of acidic deposition on the erosion of carbonate stone — experimental results from the U.S. National Acid Precipitation Assessment Program (NAPAP)

NASA Astrophysics Data System (ADS)

Baedecker, Philip A.; Reddy, Michael M.; Reimann, Karl J.; Sciammarella, Cesar A.

One of the goals of NAPAP-sponsored research on the effects of acidic deposition on carbonate stone has been to quantify the incremental effects of wet and dry deposition of hydrogen ion, sulfur dioxide and nitrogen oxides on stone erosion. Test briquettes and slabs of freshly quarried Indiana limestone and Vermont marble have been exposed to ambient environmental conditions in a long-term exposure program. Physical measurements of the recession of test stones exposed to ambient conditions at an angle of 30° to horizontal at the five NAPAP materials exposure sites range from ˜ 15 to ˜ 30 μm yr -1 for marble, and from ˜ 25 to ˜ 45 μm yr -1 for limestone, and are approximately double the recession estimates based on the observed calcium content of run-off solutions from test slabs. The difference between the physical and chemical recession measurements is attributed to the loss of mineral grains from the stone surfaces that are not measured in the run-off experiments. The erosion due to grain loss does not appear to be influenced by rainfall acidity, however, preliminary evidence suggests that grain loss may be influenced by dry deposition of sulfur dioxide between rainfall events. Chemical analyses of the run-off solutions and associated rainfall blanks suggest that ˜ 30% of erosion by dissolution can be attributed to the wet deposition of hydrogen ion and the dry deposition of sulfur dioxide and nitric acid between rain events. The remaining ˜ 70% of erosion by dissolution is accounted for by the solubility of carbonate stone in rain that is in equilibrium with atmospheric carbon dioxide ("clean rain"). These results are for marble and limestone slabs exposed at an angle of 30° from horizontal. The relative contribution of sulfur dioxide to chemical erosion is significantly enhanced for stone slabs having an inclination of 60° or 85°. The dry deposition of alkaline particulate material has a mitigating effect at the two urban field exposure sites at Washington, DC, and Steubenville, OH.

Effects of acidic deposition on the erosion of carbonate stone - experimental results from the U.S. National Acid Precipitation Assessment Program (NAPAP)

USGS Publications Warehouse

Baedecker, P.A.; Reddy, M.M.; Reimann, K.J.; Sciammarella, C.A.

1992-01-01

One of the goals of NAPAP-sponsored research on the effects of acidic deposition on carbonate stone has been to quantify the incremental effects of wet and dry deposition of hydrogen ion, sulfur dioxide and nitrogen oxides on stone erosion. Test briquettes and slabs of freshly quarried Indiana limestone and Vermont marble have been exposed to ambient environmental conditions in a long-term exposure program. Physical measurements of the recession of test stones exposed to ambient conditions at an angle of 30?? to horizontal at the five NAPAP materials exposure sites range from ~15 to ~30?? ??m yr-1 for marble, and from ~25 to ~45 ??m yr -1 for limestone, and are approximately double the recession estimates based on the observed calcium content of run-off solutions from test slabs. The difference between the physical and chemical recession measurements is attributed to the loss of mineral grains from the stone surfaces that are not measured in the run-off experiments. The erosion due to grain loss does not appear to be influenced by rainfall acidity, however, preliminary evidence suggests that grain loss may be influenced by dry deposition of sulfur dioxide between rainfall events. Chemical analyses of the run-off solutions and associated rainfall blanks suggest that ~30% of erosion by dissolution can be attributed to the wet deposition of hydrogen ion and the dry deposition of sulfur dioxide and nitric acid between rain events. The remaining ~70% of erosion by dissolution is accounted for by the solubility of carbonate stone in rain that is in equilibrium with atmospheric carbon dioxide ('clean rain'). These results are for marble and limestone slabs exposed at an angle of 30?? from horizontal. The relative contribution of sulfur dioxide to chemical erosion is significantly enhanced for stone slabs having an inclination of 60?? or 85??. The dry deposition of alkaline particulate material has a mitigating effect at the two urban field exposure sites at Washington, DC, and Steubenville, OH.

Studies of the Influence of Beam Profile and Cooling Conditions on the Laser Deposition of a Directionally-Solidified Superalloy.

PubMed

Yang, Shuo; Du, Dong; Chang, Baohua

2018-02-04

In the laser deposition of single crystal and directionally-solidified superalloys, it is desired to form laser deposits with high volume fractions of columnar grains by suppressing the columnar-to-equiaxed transition efficiently. In this paper, the influence of beam profile (circular and square shapes) and cooling conditions (natural cooling and forced cooling) on the geometric morphology and microstructure of deposits were experimentally studied in the laser deposition of a directionally-solidified superalloy, IC10, and the mechanisms of influence were revealed through a numerical simulation of the thermal processes during laser deposition. The results show that wider and thinner deposits were obtained with the square laser beam than those with the circular laser beam, regardless of whether natural or forced cooling conditions was used. The heights and contact angles of deposits were notably increased due to the reduced substrate temperatures by the application of forced cooling for both laser beam profiles. Under natural cooling conditions, columnar grains formed epitaxially at both the center and the edges of the deposits with the square laser beam, but only at the center of the deposits with the circular laser beam; under forced cooling conditions, columnar grains formed at both the center and the edges of deposits regardless of the laser beam profile. The high ratios of thermal gradient and solidification velocity in the height direction of the deposits were favorable to forming deposits with higher volume fractions of columnar grains.

Studies of the Influence of Beam Profile and Cooling Conditions on the Laser Deposition of a Directionally-Solidified Superalloy

PubMed Central

Yang, Shuo; Du, Dong

2018-01-01

In the laser deposition of single crystal and directionally-solidified superalloys, it is desired to form laser deposits with high volume fractions of columnar grains by suppressing the columnar-to-equiaxed transition efficiently. In this paper, the influence of beam profile (circular and square shapes) and cooling conditions (natural cooling and forced cooling) on the geometric morphology and microstructure of deposits were experimentally studied in the laser deposition of a directionally-solidified superalloy, IC10, and the mechanisms of influence were revealed through a numerical simulation of the thermal processes during laser deposition. The results show that wider and thinner deposits were obtained with the square laser beam than those with the circular laser beam, regardless of whether natural or forced cooling conditions was used. The heights and contact angles of deposits were notably increased due to the reduced substrate temperatures by the application of forced cooling for both laser beam profiles. Under natural cooling conditions, columnar grains formed epitaxially at both the center and the edges of the deposits with the square laser beam, but only at the center of the deposits with the circular laser beam; under forced cooling conditions, columnar grains formed at both the center and the edges of deposits regardless of the laser beam profile. The high ratios of thermal gradient and solidification velocity in the height direction of the deposits were favorable to forming deposits with higher volume fractions of columnar grains. PMID:29401715

Apparatus for laser assisted thin film deposition

DOEpatents

Warner, B.E.; McLean, W. II

1996-02-13

A pulsed laser deposition apparatus uses fiber optics to deliver visible output beams. One or more optical fibers are coupled to one or more laser sources, and delivers visible output beams to a single chamber, to multiple targets in the chamber or to multiple chambers. The laser can run uninterrupted if one of the deposition chambers ceases to operate because other chambers can continue their laser deposition processes. The laser source can be positioned at a remote location relative to the deposition chamber. The use of fiber optics permits multi-plexing. A pulsed visible laser beam is directed at a generally non-perpendicular angle upon the target in the chamber, generating a plume of ions and energetic neutral species. A portion of the plume is deposited on a substrate as a thin film. A pulsed visible output beam with a high pulse repetition frequency is used. The high pulse repetition frequency is greater than 500 Hz, and more preferably, greater than about 1000 Hz. Diamond-like-carbon (DLC) is one of the thin films produced using the apparatus. 9 figs.

Apparatus for laser assisted thin film deposition

DOEpatents

Warner, Bruce E.; McLean, II, William

1996-01-01

A pulsed laser deposition apparatus uses fiber optics to deliver visible output beams. One or more optical fibers are coupled to one or more laser sources, and delivers visible output beams to a single chamber, to multiple targets in the chamber or to multiple chambers. The laser can run uninterrupted if one of the deposition chambers ceases to operate because other chambers can continue their laser deposition processes. The laser source can be positioned at a remote location relative to the deposition chamber. The use of fiber optics permits multi-plexing. A pulsed visible laser beam is directed at a generally non-perpendicular angle upon the target in the chamber, generating a plume of ions and energetic neutral species. A portion of the plume is deposited on a substrate as a thin film. A pulsed visible output beam with a high pulse repetition frequency is used. The high pulse repetition frequency is greater than 500 Hz, and more preferably, greater than about 1000 Hz. Diamond-like-carbon (DLC) is one of the thin films produced using the apparatus.

Evolution of structural and optical properties of rutile TiO2 thin films synthesized at room temperature by chemical bath deposition method

NASA Astrophysics Data System (ADS)

Mayabadi, A. H.; Waman, V. S.; Kamble, M. M.; Ghosh, S. S.; Gabhale, B. B.; Rondiya, S. R.; Rokade, A. V.; Khadtare, S. S.; Sathe, V. G.; Pathan, H. M.; Gosavi, S. W.; Jadkar, S. R.

2014-02-01

Nanocrystalline thin films of TiO2 were prepared on glass substrates from an aqueous solution of TiCl3 and NH4OH at room temperature using the simple and cost-effective chemical bath deposition (CBD) method. The influence of deposition time on structural, morphological and optical properties was systematically investigated. TiO2 transition from a mixed anatase-rutile phase to a pure rutile phase was revealed by low-angle XRD and Raman spectroscopy. Rutile phase formation was confirmed by FTIR spectroscopy. Scanning electron micrographs revealed that the multigrain structure of as-deposited TiO2 thin films was completely converted into semi-spherical nanoparticles. Optical studies showed that rutile thin films had a high absorption coefficient and a direct bandgap. The optical bandgap decreased slightly (3.29-3.07 eV) with increasing deposition time. The ease of deposition of rutile thin films at low temperature is useful for the fabrication of extremely thin absorber (ETA) solar cells, dye-sensitized solar cells, and gas sensors.

Fabrication of transparent superhydrophobic polytetrafluoroethylene coating

NASA Astrophysics Data System (ADS)

Alawajji, Raad A.; Kannarpady, Ganesh K.; Biris, Alexandru S.

2018-06-01

Polytetrafluoroethylene (PTFE) thin films were successfully deposited on glass substrates using pulsed laser deposition, with deposition times ranging from 30 to 120 minutes (min). The surface roughness of the films increased as deposition time increased, with micro/nanoscale roughness developing when deposition time increased over 60 min. This roughness made the surface superhydrophobic, having a contact angle of about 151.6°±1. UV-vis spectroscopic analysis of the PTFE films revealed that they were highly transparent, up to ∼90% in visible and near-infrared ranges. Furthermore, when the deposition time was increased-which increased the films' thickness-the films were able to absorb 80-90% of ultraviolet light in the wavelength range <300 nm. The researchers used an x-ray photoelectron spectrometer to find the chemical and elemental composition of the films' surfaces. Atomic force microscopy was used to determine the effect of surface roughness on the films' hydrophobicity. The fabricated superhydrophobic films have many potential practical uses, from self-cleaning materials to solar cell panel coatings. Additionally, the low dielectric properties of PTFE make the films' ideal for communication antenna coatings and similar applications.

Unusual behavior in magnesium-copper cluster matter produced by helium droplet mediated deposition.

PubMed

Emery, S B; Xin, Y; Ridge, C J; Buszek, R J; Boatz, J A; Boyle, J M; Little, B K; Lindsay, C M

2015-02-28

We demonstrate the ability to produce core-shell nanoclusters of materials that typically undergo intermetallic reactions using helium droplet mediated deposition. Composite structures of magnesium and copper were produced by sequential condensation of metal vapors inside the 0.4 K helium droplet baths and then gently deposited onto a substrate for analysis. Upon deposition, the individual clusters, with diameters ∼5 nm, form a cluster material which was subsequently characterized using scanning and transmission electron microscopies. Results of this analysis reveal the following about the deposited cluster material: it is in the un-alloyed chemical state, it maintains a stable core-shell 5 nm structure at sub-monolayer quantities, and it aggregates into unreacted structures of ∼75 nm during further deposition. Surprisingly, high angle annular dark field scanning transmission electron microscopy images revealed that the copper appears to displace the magnesium at the core of the composite cluster despite magnesium being the initially condensed species within the droplet. This phenomenon was studied further using preliminary density functional theory which revealed that copper atoms, when added sequentially to magnesium clusters, penetrate into the magnesium cores.

Comparative Study of Solution Phase and Vapor Phase Deposition of Aminosilanes on Silicon Dioxide Surfaces

PubMed Central

Yadav, Amrita R.; Sriram, Rashmi; Carter, Jared A.; Miller, Benjamin L.

2014-01-01

The uniformity of aminosilane layers typically used for the modification of hydroxyl bearing surfaces such as silicon dioxide is critical for a wide variety of applications, including biosensors. However, in spite of many studies that have been undertaken on surface silanization, there remains a paucity of easy-to-implement deposition methods reproducibly yielding smooth aminosilane monolayers. In this study, solution- and vapor-phase deposition methods for three aminoalkoxysilanes differing in the number of reactive groups (3-aminopropyl triethoxysilane (APTES), 3-aminopropyl methyl diethoxysilane (APMDES) and 3-aminopropyl dimethyl ethoxysilane (APDMES)) were assessed with the aim of identifying methods that yield highly uniform and reproducible silane layers that are resistant to minor procedural variations. Silane film quality was characterized based on measured thickness, hydrophilicity and surface roughness. Additionally, hydrolytic stability of the films was assessed via these thickness and contact angle values following desorption in water. We found that two simple solution-phase methods, an aqueous deposition of APTES and a toluene based deposition of APDMES, yielded high quality silane layers that exhibit comparable characteristics to those deposited via vapor-phase methods. PMID:24411379

Tantalum films with well-controlled roughness grown by oblique incidence deposition

NASA Astrophysics Data System (ADS)

Rechendorff, K.; Hovgaard, M. B.; Chevallier, J.; Foss, M.; Besenbacher, F.

2005-08-01

We have investigated how tantalum films with well-controlled surface roughness can be grown by e-gun evaporation with oblique angle of incidence between the evaporation flux and the surface normal. Due to a more pronounced shadowing effect the root-mean-square roughness increases from about 2 to 33 nm as grazing incidence is approached. The exponent, characterizing the scaling of the root-mean-square roughness with length scale (α), varies from 0.75 to 0.93, and a clear correlation is found between the angle of incidence and root-mean-square roughness.

Measurement of surface tension and viscosity by open capillary techniques

DOEpatents

Rye,Robert R. , Yost,Frederick G.

1998-01-01

An open-channel capillary is provided, having preferably a v-shaped groove in a flat wettable surface. The groove has timing marks and a source marker in which the specimen to be tested is deposited. The time of passage between the timing marks is recorded, and the ratio of surface tension .gamma. to viscosity .mu. is determined from the equation given below: ##EQU1## where h.sub.0 is the groove depth, .alpha. is the groove angle, .theta. is the liquid/solid contact angle, and t is the flow time. It has been shown by the

Optimization of Perfect Absorbers with Multilayer Structures

NASA Astrophysics Data System (ADS)

Li Voti, Roberto

2018-02-01

We study wide-angle and broadband perfect absorbers with compact multilayer structures made of a sequence of ITO and TiN layers deposited onto a silver thick layer. An optimization procedure is introduced for searching the optimal thicknesses of the layers so as to design a perfect broadband absorber from 400 nm to 750 nm, for a wide range of angles of incidence from 0{°} to 50{°}, for both polarizations and with a low emissivity in the mid-infrared. We eventually compare the performances of several optimal structures that can be very promising for solar thermal energy harvesting and collectors.

Investigation of the dependence of BLS frequencies on angle of incidence for thin iron films

NASA Astrophysics Data System (ADS)

From, M.; Cochran, J. F.; Heinrich, B.; Celinski, Z.

1993-05-01

Brillouin light-scattering experiments have been done at various angles of incidence, θ, for four specimens prepared by molecular-beam epitaxy. The specimens were single ultrathin films of Fe deposited on single-crystal Ag substrates. Dependence of magnon frequency on θ is easily resolvable in all specimens. We find that the magnitude of this dependence is in good agreement with a theoretical calculation that takes into account magnetic anisotropies, dipole-dipole, and exchange interactions. Our results imply that magnetic excitations in these specimens are correlated over distances of at least 5000 Å.

Line-of-sight deposition method

DOEpatents

Patten, J.W.; McClanahan, E.D.; Bayne, M.A.

1980-04-16

A line-of-sight method of depositing a film having substantially 100% of theoretical density on a substrate. A pressure vessel contains a target source having a surface thereof capable of emitting particles therefrom and a substrate with the source surface and the substrate surface positioned such that the source surface is substantially parallel to the direction of the particles impinging upon the substrate surface, the distance between the most remote portion of the substrate surface receiving the particles and the source surface emitting the particles in a direction parallel to the substrate surface being relatively small. The pressure in the vessel is maintained less than about 5 microns to prevent scattering and permit line-of-sight deposition. By this method the angles of incidence of the particles impinging upon the substrate surface are in the range of from about 45/sup 0/ to 90/sup 0/ even when the target surface area is greatly expanded to increase the deposition rate.

Gold Veins near Great Falls, Maryland

USGS Publications Warehouse

Reed, John Calvin; Reed, John C.

1969-01-01

Small deposits of native gold are present along an anastomosing system of quartz veins and shear zones just east of Great Falls, Montgomery County, Md. The deposits were discovered in 1861 and were worked sporadically until 1951, yielding more than 5,000 ounces of gold. The vein system and the principal veins within it strike a few degrees west of north, at an appreciable angle to foliation and fold axial planes in enclosing rocks of the Wissahickon Formation of late Precambrian (?) age. The veins cut granitic rocks of Devonian or pre-Devonian age and may be as young as Triassic. Further development of the deposits is unlikely under present economic conditions because of their generally low gold content and because much of the vein system lies on park property, but study of the Great Falls vein system may be useful in the search for similar deposits elsewhere in the Appalachian Piedmont.

Oriented polyvinylidene fluoride–trifluoroethylene (P(VDF–TrFE)) films by Langmuir–Blodgett deposition: A synchrotron X-ray diffraction study

DOE PAGES

Lindemann, W. R.; Philiph, R. L.; Chan, D. W. W.; ...

2015-10-07

Langmuir–Blodgett films of polyvinylidene fluoride trifluoroethylene – P(VDF–TrFE)-copolymers possess substantially improved electrocaloric and pyroelectric properties, when compared with conventionally spin-cast films. In order to rationalize this, we prepared single-layered films of P(VDF–TrFE) (70:30) using both deposition techniques. Grazing incidence wide-angle X-ray scattering (GIWAXS), reveals that Langmuir–Blodgett deposited films have a higher concentration of the ferroelectric β-phase crystals, and that these films are highly oriented with respect to the substrate. Based on these observations, we suggest alternative means of deposition, which may substantially enhance the electrocaloric effect in P(VDF–TrFE) films. As a result, this development has significant implications for the potentialmore » use of P(VDF–TrFE) in solid-state refrigeration.« less

Studies on ion scattering and sputtering processes relevant to ion beam sputter deposition of multicomponent thin films

DOE Office of Scientific and Technical Information (OSTI.GOV)

Auciello, O.; Ameen, M.S.; Kingon, A.I.

1989-01-01

Results from computer simulation and experiments on ion scattering and sputtering processes in ion beam sputter deposition of high Tc superconducting and ferroelectric thin films are presented. It is demonstrated that scattering of neutralized ions from the targets can result in undesirable erosion of, and inert gas incorporation in, the growing films, depending on the ion/target atom ass ratio and ion beam angle of incidence/target/substrate geometry. The studies indicate that sputtering Kr{sup +} or Xe{sup +} ions is preferable to the most commonly used Ar{sup +} ions, since the undesirable phenomena mentioned above are minimized for the first two ions.more » These results are used to determine optimum sputter deposition geometry and ion beam parameters for growing multicomponent oxide thin films by ion beam sputter-deposition. 10 refs., 5 figs.« less

Deposition of hydrogenated silicon clusters for efficient epitaxial growth.

PubMed

Le, Ha-Linh Thi; Jardali, Fatme; Vach, Holger

2018-06-13

Epitaxial silicon thin films grown from the deposition of plasma-born hydrogenated silicon nanoparticles using plasma-enhanced chemical vapor deposition have widely been investigated due to their potential applications in photovoltaic and nanoelectronic device technologies. However, the optimal experimental conditions and the underlying growth mechanisms leading to the high-speed epitaxial growth of thin silicon films from hydrogenated silicon nanoparticles remain far from being understood. In the present work, extensive molecular dynamics simulations were performed to study the epitaxial growth of silicon thin films resulting from the deposition of plasma-born hydrogenated silicon clusters at low substrate temperatures under realistic reactor conditions. There is strong evidence that a temporary phase transition of the substrate area around the cluster impact site to the liquid state is necessary for the epitaxial growth to take place. We predict further that a non-normal incidence angle for the cluster impact significantly facilitates the epitaxial growth of thin crystalline silicon films.

Line-of-sight deposition method

DOEpatents

Patten, James W.; McClanahan, Edwin D.; Bayne, Michael A.

1981-01-01

A line-of-sight method of depositing a film having substantially 100% of theoretical density on a substrate. A pressure vessel contains a target source having a surface thereof capable of emitting particles therefrom and a substrate with the source surface and the substrate surface positioned such that the source surface is substantially parallel to the direction of the particles impinging upon the substrate surface, the distance between the most remote portion of the substrate surface receiving the particles and the source surface emitting the particles in a direction parallel to the substrate surface being relatively small. The pressure in the vessel is maintained less than about 5 microns to prevent scattering and permit line-of-sight deposition. By this method the angles of incidence of the particles impinging upon the substrate surface are in the range of from about 45.degree. to 90.degree. even when the target surface area is greatly expanded to increase the deposition rate.

IMF Control of Alfvénic Energy Transport and Deposition at High Latitudes

NASA Astrophysics Data System (ADS)

Hatch, Spencer M.; LaBelle, James; Lotko, William; Chaston, Christopher C.; Zhang, Binzheng

2017-12-01

We investigate the influence of the interplanetary magnetic field (IMF) clock angle ϕIMF on high-latitude inertial Alfvén wave (IAW) activity in the magnetosphere-ionosphere transition region using Fast Auroral SnapshoT (FAST) satellite observations. We find evidence that negative IMF Bz coincides with nightside IAW power generation and enhanced rates of IAW-associated electron energy deposition, while positive IMF Bz coincides with enhanced dayside wave and electron energy deposition. Large (≳ 5 nT) negative IMF By coincides with enhanced postnoon IAW power, while large positive IMF By coincides with enhanced but relatively weaker prenoon IAW power. For each ϕIMF orientation we compare IAW Poynting flux and IAW-associated electron energy flux distributions with previously published distributions of Alfvénic Poynting flux over ˜2-22 mHz, as well as corresponding wave-driven electron energy deposition derived from Lyon-Fedder-Mobarry global MHD simulations. We also compare IAW Poynting flux distributions with distributions of broad and diffuse electron number flux, categorized using an adaptation of the Newell et al. (2009) precipitation scheme for FAST. Under negative IMF Bz in the vicinity of the cusp (9.5-14.5 magnetic local time), regions of intense dayside IAW power correspond to enhanced diffuse electron number flux but relatively weaker broadband electron precipitation. Differences between cusp region IAW activity and broadband precipitation illustrate the need for additional information, such as fields or pitch angle measurements, to identify the physical mechanisms associated with electron precipitation in the vicinity of the cusp.

A new temperature and humidity dependent surface site density approach for deposition ice nucleation

NASA Astrophysics Data System (ADS)

Steinke, I.; Hoose, C.; Möhler, O.; Connolly, P.; Leisner, T.

2014-07-01

Deposition nucleation experiments with Arizona Test Dust (ATD) as a surrogate for mineral dusts were conducted at the AIDA cloud chamber at temperatures between 220 and 250 K. The influence of the aerosol size distribution and the cooling rate on the ice nucleation efficiencies was investigated. Ice nucleation active surface site (INAS) densities were calculated to quantify the ice nucleation efficiency as a function of temperature, humidity and the aerosol surface area concentration. Additionally, a contact angle parameterization according to classical nucleation theory was fitted to the experimental data in order to relate the ice nucleation efficiencies to contact angle distributions. From this study it can be concluded that the INAS density formulation is a very useful tool to decribe the temperature and humidity dependent ice nucleation efficiency of ATD particles. Deposition nucleation on ATD particles can be described by a temperature and relative humidity dependent INAS density function ns(T, Sice) with ns(xtherm) = 1.88 × 105 \\centerdot exp(0.2659 \\centerdot xtherm) [m-2] (1) where the thermodynamic variable xtherm is defined as xtherm = -(T - 273.2) + (Sice-1) × 100 (2) with Sice>1 and within a temperature range between 226 and 250 K. For lower temperatures, xtherm deviates from a linear behavior with temperature and relative humidity over ice. Two different approaches for describing the time dependence of deposition nucleation initiated by ATD particles are proposed. Box model estimates suggest that the time dependent contribution is only relevant for small cooling rates and low number fractions of ice-active particles.

Mars Environmental Chamber for Dynamic Dust Deposition and Statics Analysis

NASA Technical Reports Server (NTRS)

Moeller, L. E.; Tuller, M.; Islam, M. R.; Baker, L.; Kuhlman, K.

2004-01-01

Recent observations of the 2001 dust storms encircling Mars confirm predictions of environmental challenges for exploration. Martian dust has been found to completely mantle the Martian surface over thousands of square kilometers and the opacity of airborne dust has been shown to be capable of modifying atmospheric temperature, radiative transfer and albedo. Planetary dust cycling dynamics are suggested to be a key factor in the evolution of the Martian surface. Long-term robotic and manned exploration of Mars will be confronted by dust deposition in periods of atmospheric calm and violent wind storms. Aeolian dust deposition recorded during the Mars Pathfinder mission was estimated to fall at rates of 20-45 microns per Earth year. Although many tools of exploration will be challenged by coating, adhesion, abrasion and possible chemical reaction of deposited, wind blown and actively disturbed Martian dust, solar cells are thought to be of primary concern. Recent modeling work of power output by gallium arsenide/germanium solar cells was validated by the Pathfinder Lander data and showed power output decreases of 0.1 to 0.5% per Martian day. A major determinant for the optimal positioning angle of solar panels employed in future missions is the angle of repose of the settling dust particles that is dependent on a variety of physical and chemical properties of the particles, the panel surface, and the environmental conditions on the Mars surface. While the effects of many of these factors are well understood qualitatively, quantitative analyses, especially under physical and chemical conditions prevailing on the Mars surface are lacking.

Surface properties and surficial deposits on Venus: New results from Magellan radar altimeter data analysis

NASA Astrophysics Data System (ADS)

Bondarenko, Nataliya V.; Kreslavsky, Mikhail A.

2018-07-01

Microwave remote sensing data acquired with Magellan Venus orbiter are the main source of information about the surface of the planet. We analyze variability of the backscattering function (dependence of radar cross-section on incidence angle) for steep incidence angles 0.25°-4.75° in the 75°N-55°S latitude zone with data from the Magellan radar altimeter at 12.6 cm wavelength. We show that all variability of the backscattering function can be described by three parameters, describing (1) surface reflectivity, (2) relative proportion of horizontal facets, and (3) general roughness. Analysis of maps of these parameters revealed that surficial deposits, for example, microdune fields, are abundant on Venus even in places, where they are not readily seen in the synthetic aperture radar images. Properties of surficial deposits rather than original volcanic flow roughness define the shape of the backscattering function on the majority of regional plains. A large radar-dark flow in Bereghinia Planitia has anomalously high proportion of horizontal facets, which is consistent with it being formed by a relatively recent plain-forming volcanic episode. Some crater-associated radar-dark diffuse features and splotches are also characterized by increased proportion of horizontal faces, which indicate the presence of mantles deposited from fluidized granular material. The backscattering functions of the anomalous radar-bright material of mountaintops are more consistent with the strong internal scattering hypothesis rather than the exotic surficial material hypothesis. Obtained maps can be useful for planning future lander missions to sites with access to surface material with known provenance.

Association of hypoglycaemia severity with clinical, patient‐reported and economic outcomes in US patients with type 2 diabetes using basal insulin

PubMed Central

Lee, Lulu K.; Gupta, Shaloo; Preblick, Ron

2018-01-01

Aims To evaluate the clinical and patient‐reported outcomes and healthcare utilization and costs associated with patient‐reported hypoglycaemia in US adults with type 2 diabetes (T2D) treated with basal insulin. Materials and methods This was an observational, cross‐sectional, survey‐based study of adults with T2D on basal insulin ± oral antidiabetes drugs (OADs) or rapid‐acting/premixed insulin, who had in the past ever experienced hypoglycaemia, using US data from the National Health and Wellness Survey. Eligible patients were categorized as having no hypoglycaemia (38.7%), non‐severe hypoglycaemia (55.1%), or severe hypoglycaemia (6.2%) in the preceding 3 months. Outcomes included health‐related quality of life (HRQoL), work productivity and activity impairment, healthcare resource utilization, and estimated direct and indirect costs. Multivariable regression models were performed to control for patient characteristics. Results Patients who experienced severe hypoglycaemia had significantly (P < .05) lower HRQoL scores, greater overall impairment of work productivity and activity, greater healthcare resource utilization, and higher costs compared with those who experienced non‐severe or no hypoglycaemia. Patients with non‐severe hypoglycaemia also reported an impact on the number of provider visits, indirect costs, and HRQoL. Conclusions Patients with T2D using basal insulin ± OADs or rapid‐acting/premixed insulin in the United States who experienced severe hypoglycaemia had greater impairment of activity and work productivity, utilized more healthcare resources, and incurred higher associated costs than those with non‐severe or no hypoglycaemia. The study also demonstrated the impact that non‐severe hypoglycaemic events have on economic and HRQoL outcomes. Reducing the incidence and severity of hypoglycaemia could lead to clinically meaningful improvements in HRQoL and may result in lower healthcare utilization and associated costs. PMID:29316141

Glycemic excursions are positively associated with changes in duration of asymptomatic hypoglycemia after treatment intensification in patients with type 2 diabetes.

PubMed

Wang, Jun-Sing; Lee, I-Te; Lee, Wen-Jane; Lin, Shi-Dou; Su, Shih-Li; Tu, Shih-Te; Tseng, Yao-Hsien; Lin, Shih-Yi; Sheu, Wayne Huey-Herng

2016-03-01

The aim of this study was to examine the association between glycemic excursions and duration of hypoglycemia after treatment intensification in patients with type 2 diabetes (T2D). Patients with T2D on oral anti-diabetes drug (OAD) with glycated hemoglobin (HbA1c) of 7.0-11.0% were switched to metformin monotherapy (500 mg thrice daily) for 8 weeks, followed by randomization to either glibenclamide or acarbose as add-on treatment for 16 weeks. Glycemic excursions were assessed as mean amplitude of glycemic excursions (MAGE) with 72-h ambulatory continuous glucose monitoring (CGM) before randomization and at the end of study. Hypoglycemia was defined as sensor glucose level of less than 60 mg/dl in two or more consecutive readings from CGM. A total of 50 patients (mean age 53.5 ± 8.2 years, male 48%, mean baseline HbA1c 8.4 ± 1.2%) were analyzed. Duration of hypoglycemia significantly increased after treatment with glibenclamide (from 5.5 ± 13.8 to 18.8 ± 35.8 min/day, p=0.041), but not with acarbose (from 2.9 ± 10.9 to 14.7 ± 41.9 min/day, p=0.114). Post treatment MAGE was positively associated with change from baseline in duration of hypoglycemia after treatment with either glibenclamide (β coefficient 0.345, p=0.036) or acarbose (β coefficient 0.674, p=0.046). The association remained significant after multivariate adjustment (p<0.05 for all models). Post treatment glycemic excursions are associated with changes in duration of hypoglycemia after treatment intensification with OAD in patients with T2D. Glycemic excursions should be an important treatment target for T2D to reduce the risk of hypoglycemia. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

The impact of fasting during Ramadan on the glycemic control of patients with type 2 diabetes mellitus.

PubMed

Sahin, S B; Ayaz, T; Ozyurt, N; Ilkkilic, K; Kirvar, A; Sezgin, H

2013-10-01

Millions of Muslims fast from dawn until dusk during the annual Islamic holy month of Ramadan. Most of the studies evaluating biochemical changes in diabetic patients during Ramadan showed little changes in the glycemic control. In this study, our aim was to assess the impact of fasting during Ramadan on glycemic control in patients with type 2 diabetes. We examined 122 patients with type 2 diabetes (82 female, 40 male, age 56.93 ± 9.57 years) before and after the Ramadan. 66.4% of the patients were treated with oral antidiabetic (OAD) alone, 6.5% with a combination of insulin plus OAD and 19.7% with insulin alone. 88 of 122 patients fasted during Ramadan (26.98 ± 5.93 days). Weight, body mass index (BMI), waist circumference, blood pressure, fasting plasma glucose (FPG), postprandial glucose (PPG), fructosamine, HbA1c, fasting insulin and lipid parameters were measured. The frequencies of both severe hyperglycemia and hypoglycemia were higher in the fasting group, but the difference was not significant (p=0.18). Weight, BMI, waist circumference, blood pressure, FPG (143.38 ± 52.04 vs. 139.31 ± 43.47 mg/dl) PPG (213.40 ± 98.56 vs. 215.66+109.31 mg/dl), fructosamine (314.18 ± 75.40 vs. 314.49 ± 68.36 µmol/l), HbA1c (6.33 ± 0.98 vs. 6.22 ± 0.92%) and fasting insulin (12.61 ± 8.94 vs. 10.51 ± 6.26 µU/ml) were unchanged in patients who fasted during Ramadan. Microalbuminuria significantly decreased during Ramadan (132.85 ± 197.11 vs. 45.03 ± 73.11 mg/dl). In this study, we concluded that fasting during Ramadan did not worsen the glycemic control of patients with type 2 diabetes. © J. A. Barth Verlag in Georg Thieme Verlag KG Stuttgart · New York.

The Universe Observing Center a modern center to teach and communicate astronomy

NASA Astrophysics Data System (ADS)

Ribas, Salvador J.

2011-06-01

The Universe Observing Center is one of the parts of the Parc Astronòmic Montsec (PAM). PAM is an initiative of the Catalan government, through the Consorci del Montsec (Montsec Consortium), to take advantage of the capabilities and potential of the Montsec region to develop scientific research, training and outreach activities, particularly in the field of Astronomy. The choice of the Montsec mountains to install the PAM was motivated by the magnificent conditions for observing the sky at night; the sky above Montsec is the best (natural sky free of light pollution) in Catalonia for astronomical observations. The PAM has two main parts: the Observatori Astronòmic del Montsec (OAdM) and the Universe Observing Center (COU). The OAdM is a professional observatory with an 80-cm catadioptric telescope (Joan Oró Telescope). This telescope is a robotic telescope that can be controlled from anywhere in the world via the Internet. The COU is a large multipurpose center which is intended to become an educational benchmark for teaching and communicate astronomy and other sciences in Catalonia. The management of the COU has three main goals: 1) Teach primary and secondary school students in our Educational Training Camp. 2) Teach university students housing the practical astronomy lectures of the universities. 3) Communicate astronomy to the general public. The COU comprises special areas for these purposes: the Telescopes Park with more than 20 telescopes, a coelostat for solar observations and two dome containing full-automated telescopes. The most special equipment is ``The Eye of Montsec'', with its 12m dome containing a multimedia digital planetarium and a platform for direct observation of the sky and the environment. During 2009 we expect around 10000 visitors in Montsec area to enjoy science with Montsec dark skies and an special natural environment.

Skin oxygen tension is improved by immersion in oxygen-enriched water.

PubMed

Reading, S A; Yeomans, M; Levesque, C

2013-12-01

The perceived health and physiologic functioning of skin depends on adequate oxygen availability. Economical and easily used therapeutic approaches to increase skin oxygenation could improve the subjective appearance of the skin as well as support the management of some cutaneous conditions related to chronic hypoxic ischaemia (e.g. ulcerative wounds). We have tested the hypothesis that the O2 partial pressure of skin (PskO2 ) increases during immersion in water enriched with high levels of dissolved oxygen. A commercially available device was used to produce water containing 45 to 65 mg L(-1) of dissolved O2 . Young adults (YA; n = 7), older adults (OA; n = 13) and older adults with diabetes (OAD; n = 11) completed different experiments that required them to immerse their feet in tap water (<2 mg L(-1) of O2 ; control) or O2 -enriched water (O2 -H2 O; experimental) for 30 min. Transcutaneous oximetry was used to measure PskO2 for 20 min pre- and post-immersion. Pre-immersion mean (standard deviation) PskO2 on the plantar surface of the big toe was 75 (10), 67 (10) and 65 (10) mmHg in YA, OA and OAD, respectively. Post-immersion PskO2 was 244 (25), 193 (28) and 205 (28) mmHg for the same groups. We also show that post-immersion PskO2 varies by location and with advancing age. Water is an effective vehicle for transporting dissolved O2 across the skin surface and could be used as a basis for development of economical therapeutic approaches that improve skin oxygen tension to support skin health and function. © 2013 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

Efficacy of structured education in patients with type 2 diabetes mellitus receiving insulin treatment.

PubMed

Guo, Xiao Hui; Ji, Li Nong; Lu, Ju Ming; Liu, Jie; Lou, Qing Qing; Liu, Jing; Shen, Li; Zhang, Ming Xia; Lv, Xiao Feng; Gu, Ming Jun

2014-07-01

The aim of the present study was to assess the efficacy of structured education in insulin-treated type 2 diabetes mellitus (T2DM) patients. In a 16-week open-label randomized controlled study, 1511 T2DM patients with inadequate responses to two or more oral antidiabetic drugs (OADs) for >3 months (HbA1c >7.5%) were randomized (1:1) to either an education group (structured diabetes education plus insulin therapy) or a control group (usual care plus insulin therapy). Both groups discontinued previous OADs (except biguanides and α-glucosidase inhibitors) and started twice daily injections of 30% soluble-70% isophane recombinant insulin. The primary endpoint was the change in HbA1c from baseline. Efficacy and safety data were analyzed for within- and between-group differences. Of the initial 1511 patients, 1289 completed the study (643 in the control group; 646 in the education group). At the end of the study, significant reductions in HbA1c versus baseline were evident in both groups, but the reduction was greater in the education group (2.16% vs. 2.08%; P < 0.05). A higher proportion of patients in the education group achieved target HbA1c levels <7% (43.81% vs. 36.86%; P < 0.05) and ≤6.5% (28.48% vs. 22.71%; P < 0.05). In addition, patients in the education group showed greater increments in scores and improvement in the Morisky Medication Adherence Scale (P < 0.05). The overall incidence of hypoglycemic events was similar in the two groups. Structured education can promote the ability of patients to self-manage and their compliance with medications, thereby achieving better outcomes. © 2013 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and Wiley Publishing Asia Pty Ltd.

Type 2 diabetes in Vietnam: a cross-sectional, prevalence-based cost-of-illness study.

PubMed

Le, Nguyen Tu Dang; Dinh Pham, Luyen; Quang Vo, Trung

2017-01-01

According to the International Diabetes Federation, total global health care expenditures for diabetes tripled between 2003 and 2013 because of increases in the number of people with diabetes as well as in the average expenditures per patient. This study aims to provide accurate and timely information about the economic impacts of type 2 diabetes mellitus (T2DM) in Vietnam. The cost-of-illness estimates followed a prospective, prevalence-based approach from the societal perspective of T2DM with 392 selected diabetic patients who received treatment from a public hospital in Ho Chi Minh City, Vietnam, during the 2016 fiscal year. In this study, the annual cost per patient estimate was US $246.10 (95% CI 228.3, 267.2) for 392 patients, which accounted for about 12% (95% CI 11, 13) of the gross domestic product per capita in 2017. That includes US $127.30, US $34.40 and US $84.40 for direct medical costs, direct nonmedical expenditures, and indirect costs, respectively. The cost of pharmaceuticals accounted for the bulk of total expenditures in our study (27.5% of total costs and 53.2% of direct medical costs). A bootstrap analysis showed that female patients had a higher cost of treatment than men at US $48.90 (95% CI 3.1, 95.0); those who received insulin and oral antidiabetics (OAD) also had a statistically significant higher cost of treatment compared to those receiving OAD, US $445.90 (95% CI 181.2, 690.6). The Gradient Boosting Regression (Ensemble method) and Lasso Regression (Generalized Linear Models) were determined to be the best models to predict the cost of T2DM ( R 2 =65.3, mean square error [MSE]=0.94; and R 2 =64.75, MSE=0.96, respectively). The findings of this study serve as a reference for policy decision making in diabetes management as well as adjustment of costs for patients in order to reduce the economic impact of the disease.

Efficacy and Safety of Oral Antidiabetic Drugs in Comparison to Insulin in Treating Gestational Diabetes Mellitus: A Meta-Analysis

PubMed Central

Poolsup, Nalinee; Suksomboon, Naeti; Amin, Muhammad

2014-01-01

Objective To assess the efficacy and safety of oral antidiabetic drugs (OADs) in gestational diabetes mellitus (GDM) in comparison to insulin. Methods A meta-analysis of randomized controlled trials was conducted. The efficacy and safety of OADs in comparison to insulin in GDM patients were explored. Studies were identified by conducting a literature search using the electronic databases of Medline, CENTRAL, CINAHL, LILACS, Scopus and Web of Science in addition to conducting hand search of relevant journals from inception until October 2013. Results Thirteen studies involving 2,151 patients met the inclusion criteria. These studies were randomized controlled trials of metformin and glyburide in comparison to insulin therapy. Our results indicated a significant increase in the risk for preterm births (RR, 1.51; 95% CI, 1.04–2.19, p = 0.03) with metformin compared to insulin. However, a significant decrease in the risk for gestational hypertension (RR, 0.54; 95% CI, 0.31–0.91, p = 0.02) was found. Postprandial glucose levels also decreased significantly in patients receiving metformin (MD, −2.47 mg/dL; 95% CI, −4.00, −0.94, p = 0.002). There was no significant difference between the two groups for the remaining outcomes. There were significant increases in the risks of macrosomia (RR, 2.34; 95% CI, 1.18–4.63, p = 0.03) and neonatal hypoglycemia (RR, 2.06; 95% CI, 1.27–3.34, p = 0.005) in the glyburide group compared to insulin whereas results for the other analyzed outcomes remained non-significant. Conclusion The available evidence suggests favorable effects of metformin in treating GDM patients. Metformin seems to be an efficacious alternative to insulin and a better choice than glyburide especially those with mild form of disease. PMID:25302493

Limitations of a localized surface plasmon resonance sensor on Salmonella detection

USDA-ARS?s Scientific Manuscript database

We have designed a localized surface plasmon resonance (LSPR) biosensor to perform the whole cell detection of Salmonella using gold nanoparticls fabricated by oblique angle deposition technique. The LSPR sensor showed a plasmon peak shift due to the Salmonella antigen and anti-Salmonella antibody r...

HIGH-ANGLE AEOLIAN CROSSBEDDING AT TRAIL RIDGE, FLORIDA.

USGS Publications Warehouse

Force, Eric; Garnar, Tom

1985-01-01

This paper described new evidence concerning the origin of the Trail Ridge mineral sands deposit in Florida. Rarely exposed sections of the orebody exhibit structures indicative of sand dune formation rather than coastal beach sand accumulation. The implications for mineral sands exploration, and therefore resources, in the southeastern USA are highlighted.

3D model of fault and fissures structure of the Kovdor Baddeleyite-Apatite-Magnetite Deposit (NE of the Fennoscandian Shield)

NASA Astrophysics Data System (ADS)

Zhirov, Dmitry; Klimov, Sergey

2015-04-01

The Kovdor baddeleyite-apatite-magnetite deposit (KBAMD) is represented by a large vertical ore body and is located in the southwestern part of the Kovdor ultramafic-alkaline central-type intrusion. The intrusion represents a concentrically zoned complex of rocks with an oval shape in plan, and straight zoning, which complies with the injection and displacement of each of further magma phases from the center towards the periphery. The operation of the deposit in open pits started in 1962, and nowadays, it has produced over 500,000,000 tons of ore. This is one of the largest open pits in the Kola region, which is ca. 2 km long, 1.8 km wide, and over 400 m deep. Regular structural studies has been carried out since late 1970. A unique massif of spatial data has been accumulated so far to include over 25,000 measurements of fissures and faults from the surface, ca. 20,000 measurements of fissures in the oriented drill core (over 18 km) etc. Using this data base the 3D model of fault and fissures structure was designed. The analysis of one has resulted in the identification of a series of laws and features, which are necessary to be taken into account when designing a deep open pit and mining is carried out. These are mainly aspects concerning the origin, kinematics, mechanics and ratio of spatial extension of various fault systems, variation of their parameters at deep horizons, features of a modern stress field in the country rocks, etc. The 3D model has allowed to divide the whole fracture / fissure systems of the massif rocks into 2 large groups: prototectonic system of joints, including cracks of 'liquid magmatic (carbonatite stage) contraction genesis', and newly formed faults due to the superimposed tectonic stages. With regard to the deposit scale, these are characterized as intraformational and transformational, respectively. Each group shows a set (an assemblage) of fault systems with unique features and signs, as well as regular interconnections. The prototectonic assemblage of fissures includes the following main systems: 2-3 subsystems Rd of radial with angle of dip within 65-90° (median at 78°), two subsystems S of a circular subvertical (tangential, crossing Rd) with angle of dip within 60-90° (74°), and two diagonal-conic ones: a centriclinal C dipping towards the center of the intrusion at angles of 25-55° (43°), and a periclinal P dipping from the center of the intrusion at angles of 5-35° (18°). The system of subhorizontal joints L (angle of dip within 0-12°) at deep horizons is insignificantly manifested. All the prototectonic systems are regularly interrelated, and vary asymuthal features according to the law of axial symmetry (when moving around the vertical axis of symmetry passed through the geometric center of the carbonatite intrusion). The superimposed tectonics of post-ore stages forms a few large faults and systems of rupture discontinuities. A few (up to 3) variously oriented displacements are documented in the field on kinematic features (slide furrows, oriented cleavages). They were used for reconstruction of stresses and tectonic evolution. The superimposed tectonic faulting has heterogeneous (local) distribution in the rocks of the deposit, and slight predictability of main parameters. This study was supported by the Russian Scientific Fund (project nos. 14-17-00751).

Fracture toughness of titanium-cement interfaces: effects of fibers and loading angles.

PubMed

Khandaker, Morshed; Utsaha, Khatri Chhetri; Morris, Tracy

2014-01-01

Ideal implant-cement or implant-bone interfaces are required for implant fixation and the filling of tissue defects created by disease. Micron- to nanosize osseointegrated features, such as surface roughness, fibers, porosity, and particles, have been fused with implants for improving the osseointegration of an implant with the host tissue in orthopedics and dentistry. The effects of fibers and loading angles on the interface fracture toughness of implant-cement specimens with and without fibers at the interface are not yet known. Such studies are important for the design of a long-lasting implant for orthopedic applications. The goal of this study was to improve the fracture toughness of an implant-cement interface by deposition of micron- to nanosize fibers on an implant surface. There were two objectives in the study: 1) to evaluate the influence of fibers on the fracture toughness of implant-cement interfaces with and without fibers at the interfaces, and 2) to evaluate the influence of loading angles on implant-cement interfaces with and without fibers at the interfaces. This study used titanium as the implant, poly(methyl methacrylate) (PMMA) as cement, and polycaprolactone (PCL) as fiber materials. An electrospinning unit was fabricated for the deposition of PCL unidirectional fibers on titanium (Ti) plates. The Evex tensile test stage was used to determine the interface fracture toughness (KC) of Ti-PMMA with and without PCL fibers at 0°, 45°, and 90° loading angles, referred to in this article as tension, mixed, and shear tests. The study did not find any significant interaction between fiber and loading angles (P>0.05), although there was a significant difference in the KC means of Ti-PMMA samples for the loading angles (P<0.05). The study also found a significant difference in the KC means of Ti-PMMA samples with and without fibers (P<0.05). The results showed that the addition of the micron- to nanosize PCL fibers on Ti improved the quality of the Ti-PMMA union. The results of the study are essential for fatigue testing and finite-element analysis of implant-cement interfaces to evaluate the performance of orthopedic and orthodontic implants.

Fracture toughness of titanium–cement interfaces: effects of fibers and loading angles

PubMed Central

Khandaker, Morshed; Utsaha, Khatri Chhetri; Morris, Tracy

2014-01-01

Ideal implant–cement or implant–bone interfaces are required for implant fixation and the filling of tissue defects created by disease. Micron- to nanosize osseointegrated features, such as surface roughness, fibers, porosity, and particles, have been fused with implants for improving the osseointegration of an implant with the host tissue in orthopedics and dentistry. The effects of fibers and loading angles on the interface fracture toughness of implant–cement specimens with and without fibers at the interface are not yet known. Such studies are important for the design of a long-lasting implant for orthopedic applications. The goal of this study was to improve the fracture toughness of an implant–cement interface by deposition of micron- to nanosize fibers on an implant surface. There were two objectives in the study: 1) to evaluate the influence of fibers on the fracture toughness of implant–cement interfaces with and without fibers at the interfaces, and 2) to evaluate the influence of loading angles on implant–cement interfaces with and without fibers at the interfaces. This study used titanium as the implant, poly(methyl methacrylate) (PMMA) as cement, and polycaprolactone (PCL) as fiber materials. An electrospinning unit was fabricated for the deposition of PCL unidirectional fibers on titanium (Ti) plates. The Evex tensile test stage was used to determine the interface fracture toughness (KC) of Ti–PMMA with and without PCL fibers at 0°, 45°, and 90° loading angles, referred to in this article as tension, mixed, and shear tests. The study did not find any significant interaction between fiber and loading angles (P>0.05), although there was a significant difference in the KC means of Ti–PMMA samples for the loading angles (P<0.05). The study also found a significant difference in the KC means of Ti–PMMA samples with and without fibers (P<0.05). The results showed that the addition of the micron- to nanosize PCL fibers on Ti improved the quality of the Ti–PMMA union. The results of the study are essential for fatigue testing and finite-element analysis of implant–cement interfaces to evaluate the performance of orthopedic and orthodontic implants. PMID:24729704

Dynamics of Contact Line Pinning and Depinning of Droplets Evaporating on Microribs.

PubMed

Mazloomi Moqaddam, Ali; Derome, Dominique; Carmeliet, Jan

2018-05-15

The contact line dynamics of evaporating droplets deposited on a set of parallel microribs is analyzed with the use of a recently developed entropic lattice Boltzmann model for two-phase flow. Upon deposition, part of the droplet penetrates into the space between ribs because of capillary action, whereas the remaining liquid of the droplet remains pinned on top of the microribs. In the first stage, evaporation continues until the droplet undergoes a series of pinning-depinning events, showing alternatively the constant contact radius and constant contact angle modes. While the droplet is pinned, evaporation results in a contact angle reduction, whereas the contact radius remains constant. At a critical contact angle, the contact line depins, the contact radius reduces, and the droplet rearranges to a larger apparent contact angle. This pinning-depinning behavior goes on until the liquid above the microribs is evaporated. By computing the Gibbs free energy taking into account the interfacial energy, pressure terms, and viscous dissipation due to drop internal flow, we found that the mechanism that causes the unpinning of the contact line results from an excess in Gibbs free energy. The spacing distance and the rib height play an important role in controlling the pinning-depinning cycling, the critical contact angle, and the excess Gibbs free energy. However, we found that neither the critical contact angle nor the maximum excess Gibbs free energy depends on the rib width. We show that the different terms, that is, pressure term, viscous dissipation, and interfacial energy, contributing to the excess Gibbs free energy, can be varied differently by varying different geometrical properties of the microribs. It is demonstrated that, by varying the spacing distance between the ribs, the energy barrier is controlled by the interfacial energy while the contribution of the viscous dissipation is dominant if either rib height or width is changed. Main finding of this is study is that, for microrib patterned surfaces, the energy barrier required for the contact line to depin can be enlarged by increasing the spacing or the rib height, which can be important for practical applications.

Additive Manufacturing of AlSi10Mg Alloy Using Direct Energy Deposition: Microstructure and Hardness Characterization

NASA Astrophysics Data System (ADS)

Javidani, M.; Arreguin-Zavala, J.; Danovitch, J.; Tian, Y.; Brochu, M.

2017-04-01

This paper aims to study the manufacturing of the AlSi10Mg alloy with direct energy deposition (DED) process. Following fabrication, the macro- and microstructural evolution of the as-processed specimens was initially investigated using optical microscopy and scanning electron microscopy. Columnar dendritic structure was the dominant solidification feature of the deposit; nevertheless, detailed microstructural analysis revealed cellular morphology near the substrate and equiaxed dendrites at the top end of the deposit. Moreover, the microstructural morphology in the melt pool boundary of the deposit differed from the one in the core of the layers. The remaining porosity of the deposit was evaluated by Archimedes' principle and by image analysis of the polished surface. Crystallographic texture in the deposit was also assessed using electron backscatter diffraction and x-ray diffraction analysis. The dendrites were unidirectionally oriented at an angle of 80° to the substrate. EPMA line scans were performed to evaluate the compositional variation and elemental segregation in different locations. Eventually, microhardness (HV) tests were conducted in order to study the hardness gradient in the as-DED-processed specimen along the deposition direction. The presented results, which exhibited a deposit with an almost defect free structure, indicate that the DED process can suitable for the deposition of Al-Si-based alloys with a highly consolidated structure.

The accuracy of three-dimensional fused deposition modeling (FDM) compared with three-dimensional CT-Scans on the measurement of the mandibular ramus vertical length, gonion-menton length, and gonial angle

NASA Astrophysics Data System (ADS)

Savitri, I. T.; Badri, C.; Sulistyani, L. D.

2017-08-01

Presurgical treatment planning plays an important role in the reconstruction and correction of defects in the craniomaxillofacial region. The advance of solid freeform fabrication techniques has significantly improved the process of preparing a biomodel using computer-aided design and data from medical imaging. Many factors are implicated in the accuracy of the 3D model. To determine the accuracy of three-dimensional fused deposition modeling (FDM) models compared with three-dimensional CT scans in the measurement of the mandibular ramus vertical length, gonion-menton length, and gonial angle. Eight 3D models were produced from the CT scan data (DICOM file) of eight patients at the Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, University of Indonesia, Cipto Mangunkusumo Hospital. Three measurements were done three times by two examiners. The measurements of the 3D CT scans were made using OsiriX software, while the measurements of the 3D models were made using a digital caliper and goniometry. The measurement results were then compared. There is no significant difference between the measurements of the mandibular ramus vertical length, gonion-menton length, and gonial angle using 3D CT scans and FDM 3D models. FDM 3D models are considered accurate and are acceptable for clinical applications in dental and craniomaxillofacial surgery.

Hydrophobization of epoxy nanocomposite surface with 1H,1H,2H,2H-perfluorooctyltrichlorosilane for superhydrophobic properties

NASA Astrophysics Data System (ADS)

Psarski, Maciej; Marczak, Jacek; Celichowski, Grzegorz; Sobieraj, Grzegorz B.; Gumowski, Konrad; Zhou, Feng; Liu, Weimin

2012-10-01

Nature inspires the design of synthetic materials with superhydrophobic properties, which can be used for applications ranging from self-cleaning surfaces to microfluidic devices. Their water repellent properties are due to hierarchical (micrometer- and nanometre-scale) surface morphological structures, either made of hydrophobic substances or hydrophobized by appropriate surface treatment. In this work, the efficiency of two surface treatment procedures, with a hydrophobic fluoropolymer, synthesized and deposited from 1H,1H,2H,2H-perfluorooctyltrichlorosilane (PFOTS) is investigated. The procedures involved reactions from the gas and liquid phases of the PFOTS/hexane solutions. The hierarchical structure is created in an epoxy nanocomposite surface, by filling the resin with alumina nanoparticles and micron-sized glass beads and subsequent sandblasting with corundum microparticles. The chemical structure of the deposited fluoropolymer was examined using XPS spectroscopy. The topography of the modified surfaces was characterized using scanning electron microscopy (SEM), and atomic force microscopy (AFM). The hydrophobic properties of the modified surfaces were investigated by water contact and sliding angles measurements. The surfaces exhibited water contact angles of above 150° for both modification procedures, however only the gas phase modification provided the non-sticking behaviour of water droplets (sliding angle of 3°). The discrepancy is attributed to extra surface roughness provided by the latter procedure.

Measurement of LYSO Intrinsic Light Yield Using Electron Excitation

NASA Astrophysics Data System (ADS)

Turtos, Rosana Martinez; Gundacker, Stefan; Pizzichemi, Marco; Ghezzi, Alessio; Pauwels, Kristof; Auffray, Etiennette; Lecoq, Paul; Paganoni, Marco

2016-04-01

The determination of the intrinsic light yield (LYint) of scintillating crystals, i.e. number of optical photons created per amount of energy deposited, constitutes a key factor in order to characterize and optimize their energy and time resolution. However, until now measurements of this quantity are affected by large uncertainties and often rely on corrections for bulk absorption and surface/edge state. The novel idea presented in this contribution is based on the confinement of the scintillation emission in the central upper part of a 10 mm cubic crystal using a 1.5 MeV electron beam with diameter of 1 mm. A black non-reflective pinhole aligned with the excitation point is used to fix the light extraction solid angle (narrower than total reflection angle), which then sets a light cone travel path through the crystal. The final number of photoelectrons detected using a Hamamatsu R2059 photomultiplier tube (PMT) was corrected for the extraction solid angle, the Fresnel reflection coefficient and quantum efficiency (QE) of the PMT. The total number of optical photons produced per energy deposited was found to be 40000 ph/MeV ± 9% (syst) ±3% (stat) for LYSO. Simulations using Geant4 were successfully compared to light output measurements of 2 × 2 mm2 section crystals with lengths of 5-30 mm, in order to validate the light transport model and set a limit on Light Transfer Efficiency estimations.

Geologic map of the Leadville North 7.5’ quadrangle, Eagle and Lake Counties, Colorado

USGS Publications Warehouse

Ruleman, Chester A.; Brandt, Theodore R.; Caffee, Marc W.; Goehring, Brent M.

2018-04-24

The Leadville North 7.5’ quadrangle lies at the northern end of the Upper Arkansas Valley, where the Continental Divide at Tennessee Pass creates a low drainage divide between the Colorado and Arkansas River watersheds. In the eastern half of the quadrangle, the Paleozoic sedimentary section dips generally 20–30 degrees east. At Tennessee Pass and Missouri Hill, the core of the Sawatch anticlinorium is mapped as displaying a tight hanging-wall syncline and foot-wall anticline within the basement-cored structure. High-angle, west-dipping, Neogene normal faults cut the eastern margin of the broad, Sawatch anticlinorium. Minor displacements along high-angle, east- and west-dipping Laramide reverse faults occurred in the core of the north-plunging anticlinorium along the western and eastern flanks of Missouri Hill. Within the western half of the quadrangle, Meso- and Paleoproterozoic metamorphic and igneous rocks are uplifted along the generally east-dipping, high-angle Sawatch fault system and are overlain by at least three generations of glacial deposits in the western part of the quadrangle. 10Be and 26Al cosmogenic nuclide ages of the youngest glacial deposits indicate a last glacial maximum age of about 21–22 kilo-annum and complete deglaciation by about 14 kilo-annum, supported by chronologic studies in adjacent drainages. No late Pleistocene tectonic activity is apparent within the quadrangle.

Interface plasmonic properties of silver coated by ultrathin metal oxides

NASA Astrophysics Data System (ADS)

Sytchkova, A.; Zola, D.; Grilli, M. L.; Piegari, A.; Fang, M.; He, H.; Shao, J.

2011-09-01

Many fields of high technology take advantage of conductor-dielectric interface properties. Deeper knowledge of physical processes that determine the optical response of the structures containing metal-dielectric interfaces is important for improving the performance of thin film devices containing such materials. Here we present a study on optical properties of several ultrathin metal oxides deposited over thin silver layers. Some widely used materials (Al2O3, SiO2, Y2O3, HfO2) were selected for deposition by r.f. sputtering, and the created metal-dielectric structures with two of them, alumina and silica, were investigated in this work using attenuated total reflectance (ATR) technique and by variable-angle spectroscopic ellipsometry (VASE). VASE was performed with a help of a commercial ellipsometer at various incident angles and in a wide spectral range. A home-made sample holder manufactured for WVASE ellipsometer and operational in Otto configuration has been implemented for angle-resolved and spectral ATR measurements. Simultaneous analysis of data obtained by these two independent techniques allows elaboration of a representative model for plasmonic-related phenomena at metal-dielectric interface. The optical constants of the interface layers formed between metal and ultrathin oxide layers are investigated. A series of oxides chosen for this study allows a comparative analysis aimed for selection of the most appropriate materials for different applications.

Magnetic alloy nanowire arrays with different lengths: Insights into the crossover angle of magnetization reversal process

NASA Astrophysics Data System (ADS)

Samanifar, S.; Alikhani, M.; Almasi Kashi, M.; Ramazani, A.; Montazer, A. H.

2017-05-01

Nanoscale magnetic alloy wires are being actively investigated, providing fundamental insights into tuning properties in magnetic data storage and processing technologies. However, previous studies give trivial information about the crossover angle of magnetization reversal process in alloy nanowires (NWs). Here, magnetic alloy NW arrays with different compositions, composed of Fe, Co and Ni have been electrochemically deposited into hard-anodic aluminum oxide templates with a pore diameter of approximately 150 nm. Under optimized conditions of alumina barrier layer and deposition bath concentrations, the resulting alloy NWs with aspect ratio and saturation magnetization (Ms) up to 550 and 1900 emu cm-3, respectively, are systematically investigated in terms of composition, crystalline structure and magnetic properties. Using angular dependence of coercivity extracted from hysteresis loops, the reversal processes are evaluated, indicating non-monotonic behavior. The crossover angle (θc) is found to depend on NW length and Ms. At a constant Ms, increasing NW length decreases θc, thereby decreasing the involvement of vortex mode during the magnetization reversal process. On the other hand, decreasing Ms decreases θc in large aspect ratio (>300) alloy NWs. Phenomenologically, it is newly found that increasing Ni content in the composition decreases θc. The angular first-order reversal curve (AFORC) measurements including the irreversibility of magnetization are also investigated to gain a more detailed insight into θc.

Wetting, meniscus structure, and capillary interactions of microspheres bound to a cylindrical liquid interface.

PubMed

Kim, Paul Y; Dinsmore, Anthony D; Hoagland, David A; Russell, Thomas P

2018-03-14

Wetting, meniscus structure, and capillary interactions for polystyrene microspheres deposited on constant curvature cylindrical liquid interfaces, constructed from nonvolatile ionic or oligomeric liquids, were studied by optical interferometry and optical microscopy. The liquid interface curvature resulted from the preferential wetting of finite width lines patterned onto planar silicon substrates. Key variables included sphere diameter, nominal (or average) contact angle, and deviatoric interfacial curvature. Menisci adopted the quadrupolar symmetry anticipated by theory, with interfacial deformation closely following predicted dependences on sphere diameter and nominal contact angle. Unexpectedly, the contact angle was not constant locally around the contact line, the nominal contact angle varied among seemingly identical spheres, and the maximum interface deviation did not follow the predicted dependence on deviatoric interfacial curvature. Instead, this deviation was up to an order-of-magnitude larger than predicted. Trajectories of neighboring microspheres visually manifested quadrupole-quadrupole interactions, eventually producing square sphere packings that foreshadow interfacial assembly as a potential route to hierarchical 2D particle structures.

Exploratory Decision-Tree Modeling of Data from the Randomized REACTT Trial of Tadalafil Versus Placebo to Predict Recovery of Erectile Function After Bilateral Nerve-Sparing Radical Prostatectomy.

PubMed

Montorsi, Francesco; Oelke, Matthias; Henneges, Carsten; Brock, Gerald; Salonia, Andrea; d'Anzeo, Gianluca; Rossi, Andrea; Mulhall, John P; Büttner, Hartwig

2016-09-01

Understanding predictors for the recovery of erectile function (EF) after nerve-sparing radical prostatectomy (nsRP) might help clinicians and patients in preoperative counseling and expectation management of EF rehabilitation strategies. To describe the effect of potential predictors on EF recovery after nsRP by post hoc decision-tree modeling of data from A Study of Tadalafil After Radical Prostatectomy (REACTT). Randomized double-blind double-dummy placebo-controlled trial in 423 men aged <68 yr with adenocarcinoma of the prostate (Gleason ≤7, normal preoperative EF) who underwent nsRP at 50 centers from nine European countries and Canada. Postsurgery 1:1:1 randomization to 9-mo double-blind treatment with tadalafil 5mg once a day (OaD), tadalafil 20mg on demand, or placebo, followed by a 6-wk drug-free-washout, and a 3-mo open-label tadalafil OaD treatment. Three decision-tree models, using the International Index of Erectile Function-Erectile Function (IIEF-EF) domain score at the end of double-blind treatment, washout, and open-label treatment as response variable. Each model evaluated the association between potential predictors: presurgery IIEF domain and IIEF single-item scores, surgical approach, nerve-sparing score (NSS), and postsurgery randomized treatment group. The first decision-tree model (n=422, intention-to-treat population) identified high presurgery sexual desire (IIEF item 12: ≥3.5 and <3.5) as the key predictor for IIEF-EF at the end of double-blind treatment (mean IIEF-EF: 14.9 and 11.1), followed by high confidence to get and maintain an erection (IIEF item 15: ≥3.5 and <3.5; IIEF-EF: 15.4 and 7.1). For patients meeting these criteria, additional non-IIEF-related predictors included robot-assisted laparoscopic surgery (yes or no; IIEF-EF: 19.3 and 12.6), quality of nerve sparing (NSS: <2.5 and ≥2.5; IIEF-EF: 14.3 and 10.5), and treatment with tadalafil OaD (yes and no; IIEF-EF: 17.6 and 14.3). Additional analyses after washout and open-label treatment identified high presurgery intercourse satisfaction as the key predictor. Exploratory decision-tree analyses identified high presurgery sexual desire, confidence, and intercourse satisfaction as key predictors for EF recovery. Patients meeting these criteria might benefit the most from conserving surgery and early postsurgery EF rehabilitation. Strategies for improving EF after surgery should be discussed preoperatively with all patients; this information may support expectation management for functional recovery on an individual patient level. Understanding how patient characteristics and different treatment options affect the recovery of erectile function (EF) after radical surgery for prostate cancer might help physicians select the optimal treatment for their patients. This analysis of data from a clinical trial suggested that high presurgery sexual desire, sexual confidence, and intercourse satisfaction are key factors predicting EF recovery. Patients meeting these criteria might benefit the most from conserving surgery (robot-assisted surgery, perfect nerve sparing) and postsurgery medical rehabilitation of EF. ClinicalTrials.gov, NCT01026818. Copyright © 2016. Published by Elsevier B.V.

Historic bluff retreat and stabilization at Flag Harbor, Chesapeake Bay, Maryland

USGS Publications Warehouse

Clark, Inga; Larsen, Curtis E.; McRae, Michele

2002-01-01

Studies of bluff erosion and slope stability along the western shore of Chesapeake Bay suggest relative evolution from steep, eroding coastal bluffs to stable slopes at angles of repose ca. 35 degrees over decades. Because of the dating methods in those studies, it was impossible to precisely define rates of change. The present study provides historic age control. A pair of small harbor structures were constructed in the early 1950's at Chesapeake Beach, MD to maintain a dredged channel to a small marina occupying a ravine in the Calvert Cliffs. Prior to construction, this section of shoreline was comprised of eroding steep bluffs cut into Miocene-age sediments. Downdrift erosion is now apparent south of the structures as is updrift deposition behind the northern jetty. Since construction the updrift sand body has prograded northward and progressively deposited protective beaches along the toes of the bluffs. Former eroding bluffs nearest the harbor are now stable, vegetated slopes at angles near 35 degrees. Slope angles widen to the north and to the northern limit of the sand body. Beyond this are eroding bluffs standing at angles of 70-80 degrees. The relative time required for eroding bluffs to reach stability is estimated by interpolating the distance and time for the sand body to prograde northward since harbor construction. We measured slope angles at intervals northward from the updrift structure for a distance of 2000 feet. A least squares regression of slope angle vs distance showed progressive decrease in angle from north to south. Actively eroding 70-80 degree bluffs gave way to vegetated, but slumping slopes, and finally to stable 35-degree slopes at the harbor. A relationship between time and distance along the shore allowed us to estimate a stabilization time for this location of 35-40 years. The shortness of this time scale allows us to suggest that attempts to artificially stabilize eroding bluffs along this coast is not a simple task of protecting the toes of slopes from wave action. Once shoreline retreat ends, sloughing of sediment from bluff faces gives way to longer-term landslide processes. The bluff top recedes until a stable 35-degree slope is attained. Thus, simple shoreline protection methods may not preserve property at the bluff edge.

Electrowetting on plasma-deposited fluorocarbon hydrophobic films for biofluid transport in microfluidics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bayiati, P.; Tserepi, A.; Petrou, P. S.

2007-05-15

The present work focuses on the plasma deposition of fluorocarbon (FC) films on surfaces and the electrostatic control of their wettability (electrowetting). Such films can be employed for actuation of fluid transport in microfluidic devices, when deposited over patterned electrodes. Here, the deposition was performed using C{sub 4}F{sub 8} and the plasma parameters that permit the creation of films with optimized properties desirable for electrowetting were established. The wettability of the plasma-deposited surfaces was characterized by means of contact angle measurements (in the static and dynamic mode). The thickness of the deposited films was probed in situ by means ofmore » spectroscopic ellipsometry, while the surface roughness was provided by atomic force microscopy. These plasma-deposited FC films in combination with silicon nitride, a material of high dielectric constant, were used to create a dielectric structure that requires reduced voltages for successful electrowetting. Electrowetting experiments using protein solutions were conducted on such optimized dielectric structures and were compared with similar structures bearing commercial spin-coated Teflon registered amorphous fluoropolymer (AF) film as the hydrophobic top layer. Our results show that plasma-deposited FC films have desirable electrowetting behavior and minimal protein adsorption, a requirement for successful transport of biological solutions in 'digital' microfluidics.« less

On the influence of DC electric fields on the aerosol assisted chemical vapor deposition growth of photoactive titanium dioxide thin films.

PubMed

Romero, Luz; Binions, Russell

2013-11-05

Titanium dioxide thin films were deposited on fluorine doped tin oxide glass substrate from the electric field assisted aerosol chemical vapor deposition (EACVD) reaction of titanium isopropoxide (TTIP, Ti(OC3H7)4) in toluene on glass substrates at a temperature of 450 °C. DC electric fields were generated by applying a potential difference between the electrodes of the transparent coated oxide coated glass substrates during the deposition. The deposited films were characterized using scanning electron microscopy, X-ray diffraction, atomic force microscopy, Raman spectroscopy, and UV-vis spectroscopy. The photoactivity and hydrophilicity of the deposited films were also analyzed using a dye-ink test and water-contact angle measurements. The characterization work revealed that the incorporation of DC electric fields produced significant reproducible changes in the film microstructure, preferred crystallographic orientation, roughness, and film thickness. Photocatalytic activity was calculated from the half-time (t1/2) or time taken to degrade 50% of the initial resazurin dye concentration. A large improvement in photocatalytic activity was observed for films deposited using an electric field with a strong orientation in the (004) direction (t1/2 17 min) as compared to a film deposited with no electric field (t1/2 40 min).

Compact multilayer film structure for angle insensitive color filtering.

PubMed

Yang, Chenying; Shen, Weidong; Zhang, Yueguang; Li, Kan; Fang, Xu; Zhang, Xing; Liu, Xu

2015-03-19

Here we report a compact multilayer film structure for angle robust color filtering, which is verified by theoretical calculations and experiment results. The introduction of the amorphous silicon in the proposed unsymmetrical resonant cavity greatly reduces the angular sensitivity of the filters, which is confirmed by the analysis of the phase shift within the structure. The temperature of the substrate during the deposition is expressly investigated to obtain the best optical performance with high peak reflectance and good angle insensitive color filtering by compromising the refractive index of dielectric layer and the surface roughness of the multilayer film. And the outlayer of the structure, worked as the anti-reflection layer, have an enormous impact on the filtering performance. This method, described in this paper, can have enormous potential for diverse applications in display, colorful decoration, anti-counterfeiting and so forth.

Correlation between surface properties and wettability of multi-scale structured biocompatible surfaces

NASA Astrophysics Data System (ADS)

Gorodzha, S. N.; Surmeneva, M. A.; Prymak, O.; Wittmar, A.; Ulbricht, M.; Epple, M.; Teresov, A.; Koval, N.; Surmenev, R. A.

2015-11-01

The influence of surface properties of radio-frequency (RF) magnetron deposited hydroxyapatite (HA) and Si-containing HA coatings on wettability was studied. The composition and morphology of the coatings fabricated on titanium (Ti) were characterized using atomic force microscopy (AFM) and X-ray diffraction (XRD). The surface wettability was studied using contact angle analysis. Different geometric parameters of acid-etched (AE) and pulse electron beam (PEB)-treated Ti substrates and silicate content in the HA films resulted in the different morphology of the coatings at micro- and nano- length scales. Water contact angles for the HA coated Ti samples were evaluated as a combined effect of micro roughness of the substrate and nano-roughness of the HA films resulting in higher water contact angles compared with acid-etched (AE) or pulse electron beam (PEB) treated Ti substrates.

Hydraulic droplet coarsening in open-channel capillaries

NASA Astrophysics Data System (ADS)

Warren, Patrick B.

2016-11-01

Over a range of liquid-solid contact angles, an open-channel capillary with curved or angled sides can show a maximum in the Laplace pressure as a function of the filling state. Examples include double-angle wedges, grooves scored into flat surfaces, steps on surfaces, and the groove between touching parallel cylinders. The liquid in such a channel exhibits a beading instability if the channel is filled beyond the Laplace pressure maximum. The subsequent droplet coarsening takes place by hydraulic transport through the connecting liquid columns that remain in the groove. A mean-field scaling argument predicts the characteristic droplet radius R ˜t1 /7 , as a function of time t . This is confirmed by one-dimensional simulations of the coarsening kinetics. Some remarks are also made on the spreading kinetics of an isolated drop deposited in such a channel.

Method and apparatus for inspecting conduits

DOEpatents

Spisak, Michael J.; Nance, Roy A.

1997-01-01

An apparatus and method for ultrasonic inspection of a conduit are provided. The method involves directing a first ultrasonic pulse at a particular area of the conduit at a first angle, receiving the reflected sound from the first ultrasonic pulse, substantially simultaneously or subsequently in very close time proximity directing a second ultrasonic pulse at said area of the conduit from a substantially different angle than said first angle, receiving the reflected sound from the second ultrasonic pulse, and comparing the received sounds to determine if there is a defect in that area of the conduit. The apparatus of the invention is suitable for carrying out the above-described method. The method and apparatus of the present invention provide the ability to distinguish between sounds reflected by defects in a conduit and sounds reflected by harmless deposits associated with the conduit.

Controlled growth of 3C-SiC and 6H-SiC films on low-tilt-angle vicinal (0001) 6H-SiC wafers

NASA Technical Reports Server (NTRS)

Powell, J. A.; Petit, J. B.; Edgar, J. H.; Jenkins, I. G.; Matus, L. G.

1991-01-01

It has been found that, with proper pregrowth surface treatment, 6H-SiC single-crystal films can be grown by chemical vapor deposition (CVD) at 1450 C on vicinal (0001) 6H-SiC with tilt angles as small as 0.1 deg. Previously, tilt angles of greater than 1.5 deg were required to achieve 6H on 6H at this growth temperature. In addition, 3C-SiC could be induced to grow within selected regions on the 6H substrate. the 3C regions contained few (or zero) double-positioning boundaries and a low density of stacking faults. A new growth model is proposed to explain the control of SiC polytype in this epitaxial film growth process.

Localization and physical properties experiments conducted by Spirit at Gusev crater

USGS Publications Warehouse

Arvidson, R. E.; Anderson, R.C.; Bartlett, P.; Bell, J.F.; Blaney, D.; Christensen, P.R.; Chu, P.; Crumpler, L.; Davis, K.; Ehlmann, B.L.; Fergason, R.; Golombek, M.P.; Gorevan, S.; Grant, J. A.; Greeley, R.; Guinness, E.A.; Haldemann, A.F.C.; Herkenhoff, K.; Johnson, J.; Landis, G.; Li, R.; Lindemann, R.; McSween, H.; Ming, D. W.; Myrick, T.; Richter, L.; Seelos, F.P.; Squyres, S. W.; Sullivan, R.J.; Wang, A.; Wilson, Jim

2004-01-01

The precise location and relative elevation of Spirit during its traverses from the Columbia Memorial station to Bonneville crater were determined with bundle-adjusted retrievals from rover wheel turns, suspension and tilt angles, and overlapping images. Physical properties experiments show a decrease of 0.2% per Mars solar day in solar cell output resulting from deposition of airborne dust, cohesive soil-like deposits in plains and hollows, bright and dark rock coatings, and relatively weak volcanic rocks of basaltic composition. Volcanic, impact, aeolian, and water-related processes produced the encountered landforms and materials.

Fabrication of high temperature superconductors

DOEpatents

Balachandran, Uthamalingam; Dorris, Stephen E.; Ma, Beihai; Li, Meiya

2003-06-17

A method of forming a biaxially aligned superconductor on a non-biaxially aligned substrate substantially chemically inert to the biaxially aligned superconductor comprising is disclosed. A non-biaxially aligned substrate chemically inert to the superconductor is provided and a biaxially aligned superconductor material is deposited directly on the non-biaxially aligned substrate. A method forming a plume of superconductor material and contacting the plume and the non-biaxially aligned substrate at an angle greater than 0.degree. and less than 90.degree. to deposit a biaxially aligned superconductor on the non-biaxially aligned substrate is also disclosed. Various superconductors and substrates are illustrated.

Formation of TiO2 nanorings due to rapid thermal annealing of swift heavy ion irradiated films.

PubMed

Thakurdesai, Madhavi; Sulania, I; Narsale, A M; Kanjilal, D; Bhattacharyya, Varsha

2008-09-01

Amorphous thin films of TiO2 deposited by Pulsed Laser Deposition (PLD) method are irradiated by Swift Heavy Ion (SHI) beam. The irradiated films are subsequently annealed by Rapid Thermal Annealing (RTA) method. Atomic Force Microscopy (AFM) study reveals formation of nano-rings on the surface after RTA processing. Phase change is identified by Glancing Angle X-ray Diffraction (GAXRD) and Raman spectroscopy. Optical characterisation is carried out by UV-VIS absorption spectroscopy. Though no shift of absorption edge is observed after irradiation, RTA processing does show redshift.

Self-standing crystalline TiO2 nanotubes/CNTs heterojunction membrane: synthesis and characterization.

PubMed

Hesabi, Zohreh R; Allam, Nageh K; Dahmen, Klaus; Garmestani, Hamid; A El-Sayed, Mostafa

2011-04-01

In the present study, we report for the first time synthesis of TiO(2) nanotubes/CNTs heterojunction membrane. Chemical vapor deposition (CVD) of CNTs at 650 °C in a mixture of H(2)/He atmosphere led to in situ detachment of the anodically fabricated TiO(2) nanotube layers from the Ti substrate underneath. Morphological and structural evolution of TiO(2) nanotubes after CNTs deposition were investigated by field- emission scanning electron microscopy (FESEM), glancing angle X-ray diffraction (GAXRD), and X-ray photoelectron spectroscopy (XPS) analyses. © 2011 American Chemical Society

Localization and physical properties experiments conducted by Spirit at Gusev Crater.

PubMed

Arvidson, R E; Anderson, R C; Bartlett, P; Bell, J F; Blaney, D; Christensen, P R; Chu, P; Crumpler, L; Davis, K; Ehlmann, B L; Fergason, R; Golombek, M P; Gorevan, S; Grant, J A; Greeley, R; Guinness, E A; Haldemann, A F C; Herkenhoff, K; Johnson, J; Landis, G; Li, R; Lindemann, R; McSween, H; Ming, D W; Myrick, T; Richter, L; Seelos, F P; Squyres, S W; Sullivan, R J; Wang, A; Wilson, J

2004-08-06

The precise location and relative elevation of Spirit during its traverses from the Columbia Memorial station to Bonneville crater were determined with bundle-adjusted retrievals from rover wheel turns, suspension and tilt angles, and overlapping images. Physical properties experiments show a decrease of 0.2% per Mars solar day in solar cell output resulting from deposition of airborne dust, cohesive soil-like deposits in plains and hollows, bright and dark rock coatings, and relatively weak volcanic rocks of basaltic composition. Volcanic, impact, aeolian, and water-related processes produced the encountered landforms and materials.

Low-damage high-throughput grazing-angle sputter deposition on graphene

NASA Astrophysics Data System (ADS)

Chen, C.-T.; Casu, E. A.; Gajek, M.; Raoux, S.

2013-07-01

Despite the prevalence of sputter deposition in the microelectronics industry, it has seen very limited applications for graphene electronics. In this letter, we report systematic investigation of the sputtering induced damages in graphene and identify the energetic sputtering gas neutrals as the primary cause of graphene disorder. We further demonstrate a grazing-incidence sputtering configuration that strongly suppresses fast neutral bombardment and retains graphene structure integrity, creating considerably lower damage than electron-beam evaporation. Such sputtering technique yields fully covered, smooth thin dielectric films, highlighting its potential for contact metals, gate oxides, and tunnel barriers fabrication in graphene device applications.

SERS analysis of Ag nanostructures produced by ion-beam deposition

NASA Astrophysics Data System (ADS)

Atanasov, P. A.; Nedyalkov, N. N.; Nikov, Ru G.; Grüner, Ch; Rauschenbach, B.; Fukata, N.

2018-03-01

This study deals with the development of a novel technique for formation of advanced Ag nanostructures (NSs) to be applied to high-resolution analyses based on surface enhanced Raman scattering (SERS). It has direct bearing on human health and food quality, e.g., monitoring small amount or traces of pollutants or undesirable additives. Three types of nanostructured Ag samples were produced using ion-beam deposition at glancing angle (GLAD) on quartz. All fabricated structures were covered with BI-58 pesticide (dimethoate) or Rhodamine 6G (R6G) for testing their potential for use as substrates for (SERS).

Fabrication of ultrathin multilayered superomniphobic nanocoatings by liquid flame spray, atomic layer deposition, and silanization.

PubMed

Sorvali, Miika; Vuori, Leena; Pudas, Marko; Haapanen, Janne; Mahlberg, Riitta; Ronkainen, Helena; Honkanen, Mari; Valden, Mika; Mäkelä, Jyrki M

2018-05-04

Superomniphobic, i.e. liquid-repellent, surfaces have been an interesting area of research during recent years due to their various potential applications. However, producing such surfaces, especially on hard and resilient substrates like stainless steel, still remains challenging. We present a stepwise fabrication process of a multilayered nanocoating on a stainless steel substrate, consisting of a nanoparticle layer, a nanofilm, and a layer of silane molecules. Liquid flame spray was used to deposit a TiO 2 nanoparticle layer as the bottom layer for producing a suitable surface structure. The interstitial Al 2 O 3 nanofilm, fabricated by atomic layer deposition (ALD), stabilized the nanoparticle layer, and the topmost fluorosilane layer lowered the surface energy of the coating for enhanced omniphobicity. The coating was characterized with field emission scanning electron microscopy, focused ion beam scanning electron microscopy, x-ray photoelectron spectroscopy, contact angle (CA) and sliding angle (SA) measurements, and microscratch testing. The widely recognized requirements for superrepellency, i.e. CA > 150° and SA < 10°, were achieved for deioinized water, diiodomethane, and ethylene glycol. The mechanical stability of the coating could be varied by tuning the thickness of the ALD layer at the expense of repellency. To our knowledge, this is the thinnest superomniphobic coating reported so far, with the average thickness of about 70 nm.

Fabrication of ultrathin multilayered superomniphobic nanocoatings by liquid flame spray, atomic layer deposition, and silanization

NASA Astrophysics Data System (ADS)

Sorvali, Miika; Vuori, Leena; Pudas, Marko; Haapanen, Janne; Mahlberg, Riitta; Ronkainen, Helena; Honkanen, Mari; Valden, Mika; Mäkelä, Jyrki M.

2018-05-01

Superomniphobic, i.e. liquid-repellent, surfaces have been an interesting area of research during recent years due to their various potential applications. However, producing such surfaces, especially on hard and resilient substrates like stainless steel, still remains challenging. We present a stepwise fabrication process of a multilayered nanocoating on a stainless steel substrate, consisting of a nanoparticle layer, a nanofilm, and a layer of silane molecules. Liquid flame spray was used to deposit a TiO2 nanoparticle layer as the bottom layer for producing a suitable surface structure. The interstitial Al2O3 nanofilm, fabricated by atomic layer deposition (ALD), stabilized the nanoparticle layer, and the topmost fluorosilane layer lowered the surface energy of the coating for enhanced omniphobicity. The coating was characterized with field emission scanning electron microscopy, focused ion beam scanning electron microscopy, x-ray photoelectron spectroscopy, contact angle (CA) and sliding angle (SA) measurements, and microscratch testing. The widely recognized requirements for superrepellency, i.e. CA > 150° and SA < 10°, were achieved for deioinized water, diiodomethane, and ethylene glycol. The mechanical stability of the coating could be varied by tuning the thickness of the ALD layer at the expense of repellency. To our knowledge, this is the thinnest superomniphobic coating reported so far, with the average thickness of about 70 nm.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rudeck, P.J.; Harper, J.M.E.; Fryer, P.M.

The copper concentration in aluminum--copper alloys can be altered by ion bombardment during film deposition. We have measured the sputtering yields of aluminum and copper in Al--Cu alloys as a function of the Cu concentration (5--13 at. %) and the angle of ion incidence (0--40/sup 0/ from normal). During deposition, the films were partially resputtered by 500-eV Ar/sup +/ ion bombardment from a Kaufman ion source. We found that the Cu sputtering yield decreases by up to a factor of 10 in the alloy, relative to elemental Cu. The Al sputtering yield remains close to the elemental value. The netmore » effect is a strong preferential sputtering of Al relative to Cu, which enhances the Cu concentration in an ion bombarded film. The Al/Cu sputtering yield ratio for normal incidence ion bombardment ranges from 3 to 5 as a function of Cu concentration. This ratio decreases with increasing angle of incidence to as low as 2 for 40/sup 0/ incident ions. However, since a higher fraction of the film is resputtered from a sloping surface, a higher Cu concentration is found on a sloping surface relative to a flat surface. These results show that in multicomponent film deposition under ion bombardment, the film composition will vary as a function of the surface topography. We will also show how the level of argon left trapped in the films varies inversely with respect to the ion flux.« less

Low-temperature oxidizing plasma surface modification and composite polymer thin-film fabrication techniques for tailoring the composition and behavior of polymer surfaces

NASA Astrophysics Data System (ADS)

Tompkins, Brendan D.

This dissertation examines methods for modifying the composition and behavior of polymer material surfaces. This is accomplished using (1) low-temperature low-density oxidizing plasmas to etch and implant new functionality on polymers, and (2) plasma enhanced chemical vapor deposition (PECVD) techniques to fabricate composite polymer materials. Emphases are placed on the structure of modified polymer surfaces, the evolution of polymer surfaces after treatment, and the species responsible for modifying polymers during plasma processing. H2O vapor plasma modification of high-density polyethylene (HDPE), low-density polyethylene (LDPE), polypropylene (PP), polystyrene (PS), polycarbonate (PC), and 75A polyurethane (PU) was examined to further our understanding of polymer surface reorganization leading to hydrophobic recovery. Water contact angles (wCA) measurements showed that PP and PS were the most susceptible to hydrophobic recovery, while PC and HDPE were the most stable. X-ray photoelectron spectroscopy (XPS) revealed a significant quantity of polar functional groups on the surface of all treated polymer samples. Shifts in the C1s binding energies (BE) with sample age were measured on PP and PS, revealing that surface reorganization was responsible for hydrophobic recovery on these materials. Differential scanning calorimetry (DSC) was used to rule out the intrinsic thermal properties as the cause of reorganization and hydrophobic recovery on HDPE, LDPE, and PP. The different contributions that polymer cross-linking and chain scission mechanisms make to polymer aging effects are considered. The H2O plasma treatment technique was extended to the modification of 0.2 microm and 3.0 microm track-etched polycarbonate (PC-TE) and track-etched polyethylene terephthalate (PET-TE) membranes with the goal of permanently increasing the hydrophilicity of the membrane surfaces. Contact angle measurements on freshly treated and aged samples confirmed the wettability of the membrane surfaces was significantly improved by plasma treatment. XPS and SEM analyses revealed increased oxygen incorporation onto the surface of the membranes, without any damage to the surface or pore structure. Contact angle measurements on a membrane treated in a stacked assembly suggest the plasma effectively modified the entire pore cross section. Plasma treatment also increased water flux through the membranes, with results from plasma modified membranes matching those from commercially available hydrophilic membranes (treated with wetting agent). Mechanisms for the observed modification are discussed in terms of OH and O radicals implanting oxygen functionality into the polymers. Oxidizing plasma systems (O2, CO2, H2O vapor, and formic acid vapor) were used to modify track-etched polycarbonate membranes and explore the mechanisms and species responsible for etching polycarbonate during plasma processing. Etch rates were measured using scanning electron microscopy; modified polycarbonate surfaces were further characterized using x-ray photoelectron spectroscopy and water contact angles. Etch rates and surface characterization results were combined with optical emission spectroscopy data used to identify gas-phase species and their relative densities. Although the oxide functionalities implanted by each plasma system were similar, the H2O vapor and formic acid vapor plasmas yielded the lowest contact angles after treatment. The CO2, H2O vapor, and formic acid vapor plasma-modified surfaces were, however, found to be similarly stable one month after treatment. Overall, etch rate correlated directly to the relative gas-phase density of atomic oxygen and, to a lesser extent, hydroxyl radicals. PECVD of acetic acid vapor (CH3COOH) was used to deposit films on PC-TE and silicon wafer substrates. The CH3COOH films were characterized using XPS, wCA, and SEM. This modification technique resulted in continuous deposition and self-limiting deposition of a-CxO yHz films on Si wafers and PC-TE, respectively. The self-limiting deposition on PC-TE revealed that resulting films have minimal impact on 3D PC structures. This technique would allow for more precise fabrication of patterned or nano-textured PC. PECVD is used to synthesize hydrocarbon/fluorocarbon thin films with compositional gradients by continuously changing the ratio of gases in a C 3F8/H2 plasma. The films are characterized using variable angle spectroscopic ellipsometry (VASE), Fourier transform infrared spectroscopy (FTIR), XPS, wCA, and SEM. These methods revealed that shifting spectroscopic signals can be used to characterize organization in the deposited film. Using these methods, along with gas-phase diagnostics, film chemistry and the underlying deposition mechanisms are elucidated, leading to a model that accurately predicts film thickness.

Schistura megalodon species nova, a new river loach from the Irra-waddy basin in Dehong, Yunnan, China (Teleostei: Cypriniformes: Nemacheilidae).

PubMed

Endruweit, Marco

2014-09-01

A new species of river loach, Schistura megalodon sp. nov., is described from the Irrawaddy basin in Yingjiang County, Dehong Autonomous Prefecture, Yunnan Province, China. The following combination of diagnostic characters serve to distinguish it from all other congeners in the given zoogeographical region: a large processus dentiformes in the upper jaw, a short pre-anus length of 65.4%-66.3% of SL, long paired fins (pectoral: 20.8%-24.2% of SL; pelvic: 17.9%-20.6% of SL), a wide body of 9.7%-11.3% of SL at anal fin origin, an incomplete lateral line, the absence of an orbital lobe, and a oad and distinct basicaudal bar with forward extensions.

Reversible wettability of electron-beam deposited indium-tin-oxide driven by ns-UV irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Persano, Luana; Center for Biomolecular Nanotechnologies UNILE, Istituto Italiano di Tecnologia, Via Barsanti, I-73010 Arnesano-LE; Del Carro, Pompilio

2012-04-09

Indium tin oxide (ITO) is one of the most widely used semiconductor oxides in the field of organic optoelectronics, especially for the realization of anode contacts. Here the authors report on the control of the wettability properties of ITO films deposited by reactive electron beam deposition and irradiated by means of nanosecond-pulsed UV irradiation. The enhancement of the surface water wettability, with a reduction of the water contact angle larger than 50 deg., is achieved by few tens of seconds of irradiation. The analyzed photo-induced wettability change is fully reversible in agreement with a surface-defect model, and it can bemore » exploited to realize optically transparent, conductive surfaces with controllable wetting properties for sensors and microfluidic circuits.« less

Multiple-layered effective medium approximation approach to modeling environmental effects on alumina passivated highly porous silicon nanostructured thin films measured by in-situ Mueller matrix ellipsometry

NASA Astrophysics Data System (ADS)

Mock, Alyssa; Carlson, Timothy; VanDerslice, Jeremy; Mohrmann, Joel; Woollam, John A.; Schubert, Eva; Schubert, Mathias

2017-11-01

Optical changes in alumina passivated highly porous silicon slanted columnar thin films during controlled exposure to toluene vapor are reported. Electron-beam evaporation glancing angle deposition and subsequent atomic layer deposition are utilized to deposit alumina passivated nanostructured porous silicon thin films. In-situ Mueller matrix generalized spectroscopic ellipsometry in an environmental cell is then used to determine changes in optical properties of the nanostructured thin films by inspection of individual Mueller matrix elements, each of which exhibit sensitivity to adsorption. The use of a multiple-layered effective medium approximation model allows for accurate description of the inhomogeneous nature of toluene adsorption onto alumina passivated highly porous silicon slanted columnar thin films.

Digestive kinetics determines bioavailability of pollutants. Final report, 1 June 1993--30 September 1998

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jumars, P.A.; Mayer, L.M.

1999-04-19

The authors assayed digestive capabilities of marine deposit feeders (animals that eat sediments) by using fluorescently tagged substrates and contact-angle measurements of surfactancy. Polychaetes on average showed higher enzyme activities and surfactancy than echinoderms. They found that surfactants produced by deposit feeders substantially enhance their abilities to solubilize hydrophobic pollutants such as polycyclic aromatic hydrocarbons (PAHs). Amounts solubilized were consistent with incorporation into micelles of the surfactant. Kinetics of PAH uptake could be explained by passive diffusion. The authors also found that the digestive strategies of deposit feeders often produce concentrations of proteins (digestive enzymes plus products of protein digestion)more » that are sufficient to solubilize metals. Histidine residues in these proteins were found to be critical for copper binding.« less

CVD apparatus and process for the preparation of fiber-reinforced ceramic composites

DOEpatents

Caputo, A.J.; Devore, C.E.; Lowden, R.A.; Moeller, H.H.

1990-01-23

An apparatus and process for the chemical vapor deposition of a matrix into a preform having circumferentially wound ceramic fibers, comprises heating one surface of the preform while cooling the other surface thereof. The resulting product may have fibers that are wound on radial planes or at an angle from the radial planes. The fibers can also be precoated with pyrolytic carbon before application of the matrix. The matrix is applied by passing reactant gas through the preform thereof to the other side thereof for the initial deposition of matrix near such other surface of the preform. The matrix fills in the preform from the other side surface thereof to the surface of the side of application thereof until a desired amount of matrix has been deposited. 6 figs.

CVD apparatus and process for the preparation of fiber-reinforced ceramic composites

DOEpatents

Caputo, Anthony J.; Devore, Charles E.; Lowden, Richard A.; Moeller, Helen H.

1990-01-01

An apparatus and process for the chemical vapor deposition of a matrix into a preform having circumferentially wound ceramic fibers, comprises heating one surface of the preform while cooling the other surface thereof. The resulting product may have fibers that are wound on radial planes or at an angle from the radial planes. The fibers can also be precoated with pyrolytic carbon before application of the matrix. The matrix is applied by passing reactant gas through the preform thereof to the other side thereof for the initial deposition of matrix near such other surface of the preform. The matrix fills in the preform from the other side surface thereof to the surface of the side of application thereof until a desired amount of matrix has been deposited.