Figure 3 LEE versus p-GaN thickness of the planar LED structure

Figure 3 LEE versus p-GaN thickness of the planar LED structure. LEE is plotted as a function of the p-GaN thickness for the TE (black dots) and TM (red dots) modes. Next, LEE for the nanorod LED structure is calculated. Figure  4 shows the electric field intensity distribution for the TE and TM modes. Here, the height and diameter of the rod are 1,000 and 200 nm, respectively. For the TE selleckchem mode, light emitted in the y direction can be extracted from the

nanorod and contribute to the large increase in LEE. However, light emitted in the z direction is either absorbed in the p-GaN layer or propagates in the substrate direction, which provides only a minor contribution to the LEE increase. For the TM mode, light is emitted only in the lateral directions and light propagation in the vertical direction is almost negligible as shown in Figure  4b. Therefore, the TM-polarized light can easily escape from the nanorod structure by overcoming

TIR, and consequently higher LEE than the TE mode is expected. Figure 4 Radiation patterns in the nanorod LED structure. Electric field intensity distribution of light emitted from the dipole source is shown for (a) the TE and (b) TM modes when the p-GaN thickness is 100 nm. The color scale bar represents relative strength of electric field intensity. Figure  5 shows the dependence of LEE on the diameter and height of nanorod LED structures. Here, the thickness of p-GaN layer is fixed at 100 nm. In Figure  5a, LEE is calculated as a function of the rod diameter from 40 to 500 nm when the rod height is 1,000 nm. LEE varies from 25% to 60% for the TE mode and from 40% to 70% for the TM mode as the rod diameter varies. check details When the nanorod LED structure replaces the unpatterned planar one, LEE is considerably increased. For the TM mode, LEE is increased from approximately 0.1% to >60%. As shown in Figure  5a, LEE Tyrosine-protein kinase BLK for the TM mode is higher than that for the TE mode in the nanorod LED structures. Therefore, when the TM mode emission is dominant in

the AlGaN QW of deep UV LEDs, the nanorod structure is expected to be a quite good solution for obtaining high LEE. Figure 5 LEE versus structural parameters of the nanorod LED structure. (a) LEE is plotted as a function of the diameter of a nanorod when the rod height is 1,000 nm. (b) LEE is plotted as a function of the height of a nanorod when the rod diameter is 260 nm. Results for the TE and TM modes are represented as black and red dots, respectively. In Figure  5a, some periodic behaviors of LEE with the rod diameter are observed for both the TE and TM modes. The periodic variation of LEE is basically related with resonant modes inside the nanorod structure. When a resonant mode is formed, light is confined within the nanorod structure and cannot be easily extracted, which results in the valley of LEE in Figure  5a. Therefore, it is NCT-501 important to control the rod diameter appropriately to obtain high LEE.

The ingestion of an energy drink

The ingestion of an energy drink GDC-0941 ic50 with 1 mg/kg of caffeine produced similar frequencies of side effects to the ingestion of the placebo drink. The ingestion of 3 mg/kg of caffeine in the form of an energy drink tended to increase the frequency of abdominal/gut discomfort, the incidence of see more tachycardia and heart palpitations and perceived anxiety, in comparison

to the placebo. In addition, 3 mg/kg of caffeine tended to increase the feeling of vigor and activeness in comparison to the placebo drink in the following hours after the ingestion of the drink. Table 3 Side-effects resulting from the ingestion of 1 and 3 mg/kg of caffeine using a caffeinated energy drink or the same drink without caffeine (0 mg/kg) Item 0 mg/kg 1 mg/kg 3 mg/kg Headache 8% 17% 8% Abdominal/gut discomfort 0% 0% 17% Muscle soreness 17% 17% 17% Increased vigor/activeness 17%

8% 58%* Tachycardia and heart palpitations 0% 0% 17% Insomnia 17% 8% 25% Increased urine production 8% 8% 25% Increased anxiety 0% 8% 8% * Different from 0 mg/kg (P < 0.05). Discussion The purpose of this study was to examine the effects of a caffeine-containing energy drink with a dose of 1 or 3 mg/kg of caffeine 4SC-202 research buy on muscle performance during half-squat and bench-press exercises. Findings indicate that the ingestion of the energy drink with 1 mg/kg of caffeine was not enough to raise the power output or to modify the force-velocity association during 10-to-100% 1RM power-load tests. However, the ingestion of an energy drink with 3 mg/kg of caffeine increased maximal power output by 7 ± 4% in the half-squat and by 7 ± 2% in the bench-press, in comparison to the ingestion of

a placebo energy drink (P < 0.05). In addition, 3 mg/kg of caffeine moved the relationship Montelukast Sodium found between the force production and velocity upwards in both the half-squat and the bench press. Thus, an energy drink with at least 3 mg/kg of caffeine is necessary to significantly enhance muscle performance. Apart from Seidl et al. [33] who investigated the effects of an energy drink on cognitive performance, the first authors to investigate the outcomes of caffeine-containing energy drinks on physical performance were Alford and co-workers [23]. Since then, a small number of studies have been geared to examining the effects of caffeine-containing-energy drinks on physical performance or sports tasks, mainly because of the relative novelty of these beverages [19–25, 34]. Most of them have used the most popular energy drink, Red Bull®, which contains 80 mg of caffeine per 250 mL of product (one serving).

Secretion of the HrpN harpin via the type III secretion system ma

Secretion of the HrpN harpin via the type III secretion system may promote this necrotroph-associated form of disease development [49]. The disease caused byPectobacterium carotovorumonPhyscomitrella patensclosely resembles that

caused by the necrotrophic see more fungusBotrytis cinerea[75]. The pectolytic enzymes in these pathogens could be described by “”GO: 0052042 positive regulation by symbiont of host programmed cell death”" (Figure2) as well as “”GO: 0052011 catabolism by symbiont of host cell wall pectin”". Hemibiotrophic fungal and oomycete pathogens Hemibiotrophic plant pathogens initially suppress or avoid triggering PCD during the biotrophic phase of infection, but then actively promote cell death during the GW3965 chemical structure transition to necrotrophy [33]. The mechanism(s) underlying the switch QNZ chemical structure from biotrophy to necrotrophy remain largely unknown [2]. InP. sojae, expression of the protein

toxin PsojNIP is associated with the transition to necrotrophy, and has been hypothesized to be responsible for the switch [33]. In wheat infected with the host-specific fungal pathogenMycosphaerella graminicola, disease symptoms often do not appear for several weeks. Once the necrotrophic stage begins, however, the host exhibits PCD-like characteristics, along with increased cell membrane leakage and apoplastic metabolite levels, which correlate with increased fungal growth, membrane transport, and metabolism [76]. A similar situation exists inFusarium graminearum, which lives biotrophically before switching to necrotrophy; following exposure toF. graminearum-derived trichothecene mycotoxins, multiple 2-hydroxyphytanoyl-CoA lyase barley transcripts were

detected including a PCD-related pirin [77], which may signify pathogen-triggered PCD. The effector Avr3a ofPhytophthora infestans, expressed during early infection of potato, can suppress the PCD triggered by the MAMP elicitin [78], i.e. “”GO: 0034054 negative regulation by symbiont of host defense-related programmed cell death”" (Figure2). Similarly, several effectors fromP. sojae, including Avr1b, could suppress BAX-triggered PCD, and were hypothesized to have a physiological role of suppressing defense-associated PCD [79].P. infestansAvr3a andP. sojaeAvr1b also can be described with “”GO: 0034055 positive regulation by symbiont of host defense-related programmed cell death”" (Figure2) as they trigger the host HR when the host resistance genesR3a orRps1b, respectively, are present [78,79], which underscores the complex roles of effectors and the need for careful annotation of them.

1999; Johnson et al 2000; Konermann et al 2008) In the first s

1999; Johnson et al. 2000; Konermann et al. 2008). In the first step, the gas is adsorbed onto the surface

of the membrane; in the second step the analyte molecules enter the membrane (permeation); and the third step is desorption of the molecules into the vacuum on the other side of the membrane. The gas transmission rate (k trans) across the membrane is given by Fick’s law of diffusion (Hoch and Kok 1963) $$ k_\texttrans = (P \, A \, \Updelta p)/l $$ (3)and is Tucidinostat order defined by the gas permeability (P) constant,2 the area of the membrane inlet (A), the partial pressure difference across the membrane (∆p), and the membrane thickness (l). As the partial pressure of gases on the low pressure (vacuum) side of the membrane is very small, the transmission rate is proportional to the gas concentration in the liquid phase. The overall sensitivity (gain factor) of detection is greater for thinner membranes and membrane types with high permeability. There are also effects due to relative diffusion of different molecular weight gases and “stickiness” of gas such as CO2. Therefore, for

quantitative measurements, calibrations need to be performed for each different analyte using a volume of a liquid or calibration gas. The choice of membrane depends on the experiment. If high sensitivity is required then a highly permeable membrane and a large inlet area are advantageous to facilitate a higher rate of gas sampling.

It may also be possible in some circumstances to operate with a higher vacuum to influence greater gas selleckchem transmission. In contrast, if long term sampling is required with near constant background gas concentrations, then a low consumption (i.e., thicker) membrane is required and/or use of a small sampling area. Most membranes have a good chemical resistance and if measurements are undertaken at elevated pressure (e.g., 20 bar) a supported membrane with an embedded metal grid can be used. A range of membranes suitable for MIMS applications are the following: silicone Mephenoxalone membranes (MEM-213, Mem Pro); Teflon films such as FET or AF (DuPont); silicone rubber; oxygen electrode membranes3; HDPE plastic films (various sources); silicon membranes with embedded metal grid (Franatech GmbH, Germany). Thus, the choice of MIMS sensitivity versus gas concentration stability is an important factor in the experimental design. Isotopic enrichment PHA-848125 isotopes are defined as atoms with the same number of protons, but a different number of neutrons and thus differ in atomic weight. There are 80 elements with stable isotopes (26 with only one isotope) and 94 elements that occur naturally on earth. The MIMS approach makes use of the stable isotopes which can be found at natural abundance or purchased from many suppliers in varying enrichments. Table 1 lists many elements that are useful to study with photosynthesis and respiration in plants.

01, Table 2) The effect of Bacteroidetes is also clearly shown i

01, Table 2). The effect of Bacteroidetes is also clearly shown in the RDA plot (Figure 3), which reveals the bacterial groups principally contributing to the difference among the groups of subjects. The microbiota differences selleck chemical between the health groups shown in the RDA are significant as assessed by MCPP (p= 0.01) and a total of 9.1% of the variation within the dataset could be related to the health status of the infants. In contrast to the Bacteroidetes, specific bacterial groups from the most abundant groups of the Firmicutes phylum – Clostridium clusters

IV and XIVa – were significantly more abundant in children with eczema (Table 2, Figure 4). In summary, the multiple differences in specific bacterial groups result in microbiota

profiles that are significantly distinct between healthy and eczematous infants as assessed by MCPP (p=0.01, Figure 3). Figure 2 Simpson’s reciprocal index of diversity in healthy children and children with eczema. The box extends from 25th Selleck JQEZ5 percentile to 75th percentile, with a line at the median; the whiskers extent to the highest and lowest values. * Statistically buy GDC-0973 significant difference, p=0.03. Table 2 Statistically significant differences in microbiota of healthy and eczematous children Phylum-like level Genus-like phylogenetic group Mean relative abundance* (SD) 18 months p-value Healthy Eczema   Bacteroidetes   4.20 (4.21) 1.61 (0.36) 0.01   B. fragilis et rel. 0.49 (0.74) 0.13 (0.03) 0.01   B. ovatus et rel. 0.20 (0.23) 0.09 (0.02) 0.03   B. plebeius et rel. 0.08 (0.03) 0.06 (0.01) 0.02   B. stercoris et rel. 0.08 (0.03) 0.06 (0.01) 0.02   B. uniformis et rel. 0.12 (0.21) ND < .001   B. vulgatus et rel. 1.08 (1.80) 0.23 (0.15) 0.045   P. tannerae et rel.

0.06 (0.04) ND 0.03 Clostridium cluster IV C. leptum et rel. 0.97 (1.36) 1.78 (1.19) 0.03   R. bromii et rel. 0.25 (0.44) 0.44 (0.28) 0.03   C. cellulosi et rel. Nabilone 0.81 (0.78) 1.27 (0.65) 0.03 Clostridium cluster XIVa R. lactaris et rel. 0.12 (0.16) 1.87 (2.83) 0.04   C. nexile et rel. 1.65 (0.80) 2.05 (0.85) 0.02 * % of total HITChip signal ND, below the detection level. Figure 3 RDA plot of the microbiota composition of healthy and eczematous children at 18 months of age. Responding bacterial groups that contributed more than 35% of the variability of the samples are indicated by blue arrows. P-value obtained by Monte Carlo Permutation Procedure was 0.01. Abbreviations: B., Bacteroides, C., Clostridium, L., Lactobacillus, E., Eggerthella, Eub., Eubacterium, P., Papillibacter, R., Ruminococcus. Figure 4 Relative contribution of phylum-like bacterial groups to the total HITChip signals of healthy and eczematous infants at 6 and 18 months of age. Groups contributing for at least 1% to the profiles are presented in the legend. * Statistically significant difference between healthy children and children with eczema at 18 months (p= 0.01).

Inflammation and atrophy connections Digestive and

Liver

Inflammation and atrophy connections. Digestive and

Liver Disease 2004, 36:327–332.PubMedCrossRef 40. Shim KS, Kim KH, Park BW, et al.: Increased serum levels of mutant p53 proteins in patients with colorectal cancer. J Korean Med Sci 1998, 13:44–48.PubMed 41. Suwa H, Ohshio G, Okada N, et al.: Clinical significance of serum p53 antigen in patients with pancreatic carcinomas. Gut 1997, 40:467–653. 42. Murakami K, Fujioka T, Mitsuishi I, Oda T, Nishizono A, Nasu M: Analysis of p53 gene mutations in Helicobacter pylori- associated gastritis mucosa in endoscopic biopsy specimens. Scand J Gastroenterol 1999,34(5):474–477.PubMedCrossRef 43. Konturek PC, Konturek SJ: Role of Helicobacter pylori infection in gastro-duodenal secretion

and in pathogenesis of peptic ulcer and gastritis. J Physiol Pharmacol 1994, 45:333–350.PubMed 44. Shiao YH, Rugge M, Correa P, Lehmann HP, Scheer WD: p53 alteration in learn more gastric MDV3100 precancerous lesions. Am J Pathol 1994,144(3):511–7.PubMed 45. Son HJ, Rhee JC, Park DI, Kim YH, Rhee PL, Koh KC, Paik SW, Choi KW, Kim JJ: Inducible nitric oxide synthase expression in gastroduodenal diseases infected with Helicobacter pylori. Helicobacter 2001,6(1):37–43.PubMedCrossRef 46. Farinati F, Della-Libera G, Cardin R, www.selleckchem.com/products/Gefitinib.html et al.: Gastric antioxidant, nitrites, and mucosal lipoperoxidation in chronic gastritis and Helicobacter pylori infection. J Clin Gastroenterol 1996, 22:275–281.PubMedCrossRef 47. Sanderson MJ, White KL, Drake IM, Schorach CJ: Vitamin E and carotenoids in gastric biopsies: the relation to plasma concentrations in patients with and without Helicobacter pylori gastritis. Am J Clin Nutr 1997, 65:101–106.PubMed 48. Farinati F, Cardin R, Degan P, et al.: Oxidative DNA damage accumulation in gastric carcinogenesis. Gut 1998, 42:351–6.PubMedCrossRef 49. Danese S, Cremonini F, Armuzzi A, et al.: Helicobacter pylori CagA-positive strains affect oxygen free radicals generation by gastric mucosa. Scand J Gastroenterol 2001, 36:247–50.PubMedCrossRef 50. Xia HH, Cell press Talley NJ: Apoptosis in gastric epithelium

induced by Helicobacter pylori infection: implications in gastric carcinogenesis. Am J Gastroenterol 2001,96(1):16–26.PubMedCrossRef Authors’ contributions JB, conceived of the study and participated in its design and coordination work. VG, AA and AL have made substantial contributions to patients sample collection and acquisition of data. GS, participated performed the statistical analysis. MD carrier out the ELISA studies. AS have made contribution to design, data analysis, interpretation of data, and drafting the manuscript. All authors read and approved the final manuscript.”
“Introduction Each year, more than 200,000 women are diagnosed with ovarian cancer. Ovarian cancer is the 8th most common cancer in women and the 2nd most common type of gynecological cancer in the world.

1% BSA before plating cells Plates were again washed with PBS an

1% BSA before plating cells. Plates were again washed with PBS and air-dried. SMMC-7721 cells were preincubated with CXCL12 (100 ng/ml) for 24 h at 37°C. A cell suspension containing 2 × 105 cells/ml was prepared in serum free media. The cell suspension (150 μl) was added to the inside of each well (BSA-coated wells were provided as a negative control).

Cells were allowed to attach for 1 h at 37°C. Subsequently, unattached cells were removed by gentle washing 3 times with PBS. Then the attached cells were stained with 1% crystal violet. Each well was gently washed 3 times with GSK458 order PBS. The total crystal violet bound to the cells was eluted with 10% acetic acid and measured by the absorbance at 560 nm. All the experiments were repeated 3 times in duplicate wells. ELISA for VEGF SMMC-7721 cells were plated in 24-well tissue culture plates at a density of 1 × 105 cells per well and followed with serum starvation for 24 h with RPMI-1640. Then, cells were treated with recombinant human CXCL12 (100 ng/ml)(Peprotech, UK), and the supernatants were collected 24 h after treatment. VEGF concentration was determined using Quantikine

ELISA kits according to the manufacturer’s instructions (R&D Systems, Minneapolis, MN). In vitro tube formation coculture assay To perform the tube formation assay, Transwell chambers were precoated with growth factor-reduced LY294002 Matrigel (200 μL of 10 mg/mL). Control, NC and CXCR7 shRNA transfected cells were seeded at a density of 2 × 104 cells/well in 24-well plates and cultured for 24 h respectively. HUVECs (2 × 104 cells/well) were then seeded in Transwell chambers precoated with the Matrigel. Subsequently, Transwell chambers containing HUVECs were inserted into the 24-well plates and cocultured for 24 h. After 24 h of cocultured at 37°C and 5% CO2, the number of capillary-like tubes from three randomly chosen fields was counted and photographed under an Nikon inverted microscope (Japan). Immunohistochemistry and quantitation of microvessel density Immunohistochemistry was used to analyze

the expression of CXCR7 and CD31. Paraffin-embedded human hepatocellular carcinoma tissues were sectioned at 5 μm thickness. Tumors established in nude mice were isolated and fixed Thiamine-diphosphate kinase in 4% paraformaldehyde, embedded in paraffin, and cut in 6 μm sections. Tumor sections were deparaffinized, rehydrated, and quenched with 3% hydrogen peroxide for 10 min at room temperature. The sections were incubated in protein blocking solution (5% normal horse serum, 1% goat serum in PBS) for 10 min before the addition of the primary antibody. The sections were incubated for 2 h at 37°C with rat AZD1152 manufacturer antimouse CD31 (BD Biosciences, USA) or rabbit antihuman CXCR7 (Abcam, UK) at 1:100 dilutions. After incubation, the sections were washed in PBS for 10 min, and anti-mouse or anti-rabbit secondary biotinylated antibody was applied.

05) between the BA (3120 ± 244 kcal) and placebo (2775 ± 209 kcal

05) between the BA (3120 ± 244 kcal) and placebo (2775 ± 209 kcal) groups. Furthermore, there were no differences in macronutrient daily intake, with both groups consuming

47% of their daily calories from carbohydrates, 34% from fat and 16% from protein. Training Volume There was a significant main effect for time (p < 0.01) for both training volume (watts) and training time (seconds). However, there was no significant difference between groups for either volume (Figure 2A) or time (Figure 2B), at any time point (weeks 1–6). Although not significant, the BA group consistently trained at higher workloads and for longer time periods. Discussion The current study is the first to examine the effects of concurrent high-intensity interval training (HIIT) and β-alanine supplementation on a series of physiological and performance variables. The primary findings support the use of HIIT as an advantageous training Dorsomorphin datasheet tool. Furthermore, the current study also

proposes the use of β-alanine supplementation to enhance the benefits of HIIT, by possibly improving muscle buffer capacity after six weeks of training and supplementing. The maximal oxygen uptake and time to reach maximum oxygen consumption (VO2peak, VO2TTE) and total work done (TWD) increased significantly in both training groups (β-alanine and placebo) over a six week HIIT protocol (Table 1). However, β-alanine supplementation appeared to have a greater influence on VO2peak and 3-MA in vitro Coproporphyrinogen III oxidase VO2TTE, resulting in a significant (p < 0.05) increase during the second three weeks of training, while no change occurred in placebo group. In addition, TWD significantly (p < 0.05) increased during the last three weeks by 32% and 18%

for the β-alanine and Placebo groups, respectively. Improvements in VT were also AZD5582 mouse reported for both training groups, however the placebo group demonstrated significant improvements during the last three week training phase (Table 1). Lastly, the present study also identified a significant change in lean body mass for the β-alanine supplementing group after three weeks, with no change in the placebo group. Enhanced VO2peak, VO2TTE, and VT after training A series of HIIT interventions have suggested that interval exercise (> 80% VO2max) elicits greater gains in aerobic capacity than moderate-intensity exercise [34–36]. Consequently, the improvements reported in cardiorespiratory fitness in the current study were similar to most studies that have employed short-term (2–9 weeks) endurance interval training programs in untrained and recreationally active individuals [25, 29, 34, 37–40]. Specifically, the average reported increases in VO2peak have ranged from 6–20% in male and female populations. Although the training regimens utilized have varied slightly, all supporting studies applied a similar protocol.

The overexpression and baeR-reconstituted strains were selected o

The overexpression and baeR-reconstituted strains were selected on LB agar containing 10 μg/mL tetracycline and were further verified by PCR (Additional file 5: Figure S5D) and RT-PCR (Additional file 2: Figure S2). Southern blot hybridization Southern blot analysis was performed as reported in a previous publication [45]. Genomic DNA was extracted, and approximately 10 μg was digested with BclI overnight at 50°C. The DNA was then separated on a 0.8% agarose gel containing 1:10,000 SYBR Safe gel stain (Invitrogen, Grand Island, NY), transferred onto a positively

charged nylon ACP-196 clinical trial membrane (Pall Corporation, Port Washington, NY) via the alkaline transfer method [38], and fixed by baking at 80°C for 2 h. The membrane was hybridized with an [α-32P] dCTP-labeled baeS probe (Additional file 3:

Figure S3A) using prehybridization buffer (6× saline sodium citrate [SSC; 1× SSC is 0.15 M NaCl plus 0.015 M sodium citrate], 5× Denhardt’s reagent, 0.5% SDS, 100 μg/mL salmon sperm DNA, and 50% formamide) at 42°C overnight. The membrane was then washed and visualized by autoradiography. Time-kill assay The time-kill assays were carried out in duplicate as previously described [46] with some modifications. Briefly, cells were grown to log phase and sub-cultured into 10 mL CAMHB broth without (control) or with tigecycline (0.25 or 0.5 μg/mL) to a cell density of approximately 5 × 105 CFU/mL. The cultures were incubated in an ambient atmosphere ABT-737 nmr at 37°C. At different time points (0, 4, 8, 12, and 16 h) after inoculation, 0.1 mL of the culture was removed from each tube and 10-fold serially diluted. Then, 25 μL of each diluted cell suspension was

spotted onto LB agar in duplicate. Viable cell counts were determined, the duplicates were averaged, and the data were 4EGI-1 mouse plotted. Acknowledgements This study was supported by a grant from the National Glycogen branching enzyme Taiwan University Hospital, Chu-Tung Branch. The authors also thank Dr. Kia-Chih Chang (Tzu Chi University, Taiwan) for providing the clinical A. baumannii strains and Dr. Ming-Li Liou (Yuanpei University, Taiwan) for providing the wild-type strain. We also thank Jeng-Yi Chen for his technical assistance. Electronic supplementary material Additional file 1: Figure S1.: Verification of the baeR deletion mutants. (A) Diagram of the baeR gene and deletion mutant verification using appropriate primers. (B) Successful baeR gene fragment deletion was deduced based on a change in the PCR band size from 4539 bp to 4884 bp. (TIFF 2 MB) Additional file 2: Figure S2.: Southern blot analysis. (A) Genomic DNA from the baeR deletion mutant and the parental strain was digested by BclI. The location of the specific DNA probe is shown. (B) The bands corresponding to 6.7-kb and 2.8-kb fragments are indicated. Four independent clones of AB1026 are included.

C-V measurements are used to characterize frequency dispersion [1

C-V measurements are used to characterize frequency dispersion [17] and to obtain permittivity

of the CeO2 thin films. A typical set of C-V characteristics of the as-deposited (dashed line) under different frequencies (100 Hz, 1 kHz, 10 kHz, 100 kHz, and 1 MHz) is shown in Figure 4 for the sample deposited at 250°C. C-V measurements are carried out from strong inversion (-1 V) toward strong accumulation (2 V). Noticeable frequency dispersion on C-V curves is observed. Frequency dispersion in C-V or capacitance-frequency measurements are categorized into two parts: extrinsic and intrinsic. Extrinsic frequency dispersion includes (1) parasitic effect, (2) lossy interfacial layer effect, Selleck Torin 2 (3) surface roughness effect, (4) polysilicon depletion effect, and (5) quantum mechanical effect. For part 1 of the extrinsic frequency dispersion, parasitic effects in MOS devices contain parasitic Etomoxir ic50 resistances and capacitances such as bulk series resistances, contacts (including contact between the MOS capacitor and probe station), cables, and many other parasitic

effects. The parasitic effects can simply be minimized by using suitable cables and Batimastat research buy also by depositing an aluminum thin film at the back of a large-area silicon substrate. For the cerium oxide samples, the aluminum back contact and substrate area is approximately 2 × 2 cm2. Concerning Aspartate part 2, the existence of extrinsic frequency dispersion in some high-k materials (LaAlO3) is mainly due to the effect of the lossy interfacial layer between the high-k thin film and silicon substrate on the MOS capacitor. Relative thicker thickness of the high-k thin film than the interfacial layer significantly

prevented frequency dispersion. For the cerium oxide samples, the high-k thin film thicknesses for 150°C, 200°C, 250°C, 300°C, and 350°C are 51, 43, 50, 31, and 44 nm, respectively, from spectroscopic ellipsometry. The SiO2 interfacial layer thickness is approximately 1.6 nm, which leads to much larger capacitance than the high-k thin film. Thus, lossy interfacial layer effect is excluded for the cerium oxide samples. In terms of part 3, the surface roughness is not responsible for the observed extrinsic frequency dispersion of the high-k thin films used in the paper. With respect to part 4, the poly depletion effect will become more significant leading to reduced surface potential, channel current, and gate capacitance. However, the polysilicon depletion effect is not under consideration for the samples here because the gates of the MOS capacitor samples were Au-fabricated by thermal evaporation through a shadow mask. Finally, as regards part 5, for oxide thickness down towards 1 to 3 nm, the quantum mechanical effect should be taken into account. The cerium oxide samples are not suitable for the domain (greater than 30 nm at least).