Electrical characterization of plasma-enhanced Cvd silicon nitride dielectric on copper

In this work, a novel metal-insulator-metal (MIM) capacitor process is introduced and integrated in a Copper Interconnect technology, whose smallest feature size is 0.18mum process, which has good yield, reliability and repeatability. The MIM uses a one-photomask process and hence is termed as the Low-cost-integration (LCI) MIM. The LCI MIM uses copper as the bottom electrode, plasma enhanced silicon nitride as the dielectric, and Tantalum nitride as the top electrode. The target capacitance density is 1.5fF/mum2. The target leakage current is 1e-7A/cm2 at 3.3V at 125°C. The maximum operating voltages that the MIM is designed for is 5V. The voltage linearity is desired to be less than 100ppm/v; The purpose of the study is to determine the feasibility of integrating the low-cost-integration (LCI) MIM capacitor and to characterize the device to ensure that it meets the above mentioned target values for the various parameters. This is done by electrically characterizing the capacitor for the capacitance change with voltage, the leakage current at accelerated voltages and the time-dependent-dielectric breakdown (TDDB) under various electric fields. (Abstract shortened by UMI.)

More on R-Union and R-Intersection of Neutrosophic Soft Cubic Set

R-unions and R-intersections, R-OR, R-AND of Neutrosophic soft cubic sets are introduced and related properties are investigated. We show that the R-union (R-intersection) of internal neutrosophic soft cubic set is also an internal neutrosophic soft cubic set. We show that the R-union and the R-intersection T-external (I-external, F-external) neutrosophic soft cubic sets are also T-external ( I-external, F-external) neutrosophic soft cubic sets. The conditions for the R-intersection of two cubic soft sets to be both an external neutrosophic soft cubic set and an internal neutrosophic soft cubic set. Further we provide a condition for the R- intersection and R union of two T-internal (I-internal, F-internal) neutrosophic soft cubic sets are T-external (I-external, F-external) neutrosophic soft cubic sets

Plithogenic Cubic Sets

In this article, using the concepts of cubic set and plithogenic set, the ideas of plithogenic fuzzy cubic set, plithogenic intuitionistic fuzzy cubic set, plithogenic neutrosophic cubic set are introduced and its corresponding internal and external cubic sets are discussed with examples

Effect of statins on lipoprotein (a) in dyslipidemic patients

Background: Elevated plasma lipoprotein (a) (Lp(a)) levels, which act synergistically with low-density lipoprotein cholesterol (LDL-C), are an independent risk factor for cardiovascular diseases (CVD). The effect of statin drugs on Lp(a) levels has not been well-demonstrated in clinical studies. This prospective, randomized, comparative clinical study with parallel treatment groups was conducted to assess the effect of simvastatin, atorvastatin and rosuvastatin, on serum Lp(a) levels and serum lipid profile, in treatment-naive dyslipidemic patients without CVD.Methods: A 12 weeks study, with 85 patients, aged 40-70 years, diagnosed with borderline high LDL-C, were assigned to three groups with their informed consents. Group A (n=28) was treated on simvastatin 20 mg/day; Group B (n=29) on atorvastatin 10 mg/day; and Group C (n=28) on rosuvastatin 5 mg/day. Patients’ lipid profile and Lp(a) levels were assessed at 0, 4th and 12th week of treatment period. Statistical analysis was done using Duncan’s test (p<0.05) and one-way ANOVA (p<0.001).Results: At the end of 12 weeks, serum Lp(a) reduction was substantial at 18.73% in atorvastatin group; at insignificant levels (3.15%) in simvastatin group, whereas an elevated level of 8.58% in Lp(a) was recorded in rosuvastatin group. All three treatment groups showed a significant positive impact on the lipid profile. No adverse drug reactions were reported.Conclusion: The impact of statin monotherapy on lipid profile doesn’t correlate with its effect on Lp(a). Atorvastatin has shown a significant reduction in Lp(a) unlike the other statins, and should be preferred in patients with increased risk of CVD

Free energy barrier for melittin reorientation from a membrane-bound state to a transmembrane state

An important step in a phospholipid membrane pore formation by melittin antimicrobial peptide is a reorientation of the peptide from a surface into a transmembrane conformation. In this work we perform umbrella sampling simulations to calculate the potential of mean force (PMF) for the reorientation of melittin from a surface-bound state to a transmembrane state and provide a molecular level insight into understanding peptide and lipid properties that influence the existence of the free energy barrier. The PMFs were calculated for a peptide to lipid (P/L) ratio of 1/128 and 4/128. We observe that the free energy barrier is reduced when the P/L ratio increased. In addition, we study the cooperative effect; specifically we investigate if the barrier is smaller for a second melittin reorientation, given that another neighboring melittin was already in the transmembrane state. We observe that indeed the barrier of the PMF curve is reduced in this case, thus confirming the presence of a cooperative effect

The cooperative behaviour of antimicrobial peptides in model membranes

A systematic analysis of the hypothesis of the antimicrobial peptides' (AMPs) cooperative action is performed by means of full atomistic molecular dynamics simulations accompanied by circular dichroism experiments. Several AMPs from the aurein family (2.5,2.6, 3.1), have a similar sequence in the first ten amino acids, are investigated in different environments including aqueous solution, trifluoroethanol (TFE), palmitoyloleoylphosphatidylethanolamine (POPE), and palmitoyloleoylphosphatidylglycerol (POPG) lipid bilayers. It is found that the cooperative effect is stronger in aqueous solution and weaker in TFE. Moreover, in the presence of membranes, the cooperative effect plays an important role in the peptide/lipid bilayer interaction. The action of AMPs is a competition of the hydrophobic interactions between the side chains of the peptides and the hydrophobic region of lipid molecules, as well as the intra peptide interaction. The aureins 2.5-COOH and 2.6-COOH form a hydrophobic aggregate to minimize the interaction between the hydrophobic group and the water. Once that the peptides reach the water/lipid interface the hydrophobic aggregate becomes smaller and the peptides start to penetrate into the membrane. In contrast, aurein 3.1-COOH forms only a transient aggregate which disintegrates once the peptides reached the membrane, and it shows no cooperativity in membrane penetratio

Entropy of Molecular Binding at Solvated Mineral Surfaces

We present thermodynamic integration simulations for the binding of mannose and methanoic acid onto the {10.4} calcite surface producing free energy of binding values of −2.89 and −1.64 kJ mol–1, respectively. We extract the entropy of binding from vacuum-based simulations and use these values to determine the entropy of binding for surface water molecules which is ∼6 J mol–1 K–1

Molecular simulations of venom peptide-membrane interactions: Progress and challenges

Because of their wide range of biological activities venom peptides are a valuable source of lead molecules for the development of pharmaceuticals, pharmacological tools and insecticides. Many venom peptides work by modulating the activity of ion channels and receptors or by irreversibly damaging cell membranes. In many cases, the mechanism of action is intrinsically linked to the ability of the peptide to bind to or partition into membranes. Thus, understanding the biological activity of these venom peptides requires characterizing their membrane binding properties. This review presents an overview of the recent developments and challenges in using biomolecular simulations to study venom peptide‐membrane interactions. The review is focused on (i) gating modifier peptides that target voltage‐gated ion channels, (ii) venom peptides that inhibit mechanosensitive ion channels, and (iii) pore‐forming venom peptides. The methods and approaches used to study venom peptide‐membrane interactions are discussed with a particular focus on the challenges specific to these systems and the type of questions that can (and cannot) be addressed using state‐of‐the‐art simulation techniques. The review concludes with an outlook on future aims and directions in the field

Three Stages of Lysozyme Thermal Stabilization by High and Medium Charge Density Anions

Addition of high and medium charge density anions (phosphate, sulfate, and chloride) to lysozyme in pure water demonstrates three stages for stabilization of the protein structure. The first two stages have a minor impact on lysozyme stability and are probably associated with direct interaction of the ions with charged and partial charges on the protein’s surface. There is a clear transition between the second and third stages; in the case of sodium chloride, disodium sulfate and disodium hydrogen phosphate this is at 550, 210, and 120 mM, respectively. Stabilization of lysozyme can be explained by the free energy required to hydrate the protein as it unfolds. At low ion concentrations, the protein’s hydration layer is at equilibrium with the bulk water. After the transition, bulk water is depleted and the protein is competing for water with the ions. With competition for water between the protein and the ions at higher salt concentrations, the free energy required to hydrate the interior of the protein rises and it is this that stabilizes the protein structure