Low dielectric constant Parylene-F-like films for intermetal dielectric applications

Cataloged from PDF version of article.We report on the dielectric properties and thermal stability of thin polymer films that art: suitable candidates for replacing silicon dioxide as the intermetal dielectric material in integrated circuits. Parylene-F-Iike films, (-CF2-C6H4-CF2-)(n), were produced by plasma deposition from a mixture of Ar and 1,4-bis(trifluoromethyl)benzene (CF3-C6H4-CF3) discharges and characterized using infrared absorption spectroscopy, spectroscopic ellipsometry, and capacitance measurements. The dielectric constant and the magnitude of the electronic and ionic contributions to the dielectric constant were determined through capacitance measurements and Kramers-Kronig analysis of the infrared absorption data. The film's dielectric constant ranges between 2 and 2.6 depending on the deposition conditions and the largest contribution to the dielectric constant is electronic. The films deposited at 300 degrees C are stable above 400 degrees C and further optimization could push this limit to as high as 500 degrees C. (C) 1999 American Institute of Physics

Genetic and environmental influence on thyroid gland volume and thickness of thyroid isthmus: a twin study.

Objectives Decreased thyroid volume has been related to increased prevalence of thyroid cancer.Subjects and methods One hundred and fourteen Hungarian adult twin pairs (69 monozygotic, 45 dizygotic) with or without known thyroid disorders underwent thyroid ultrasound. Thickness of the thyroid isthmus was measured at the thickest portion of the gland in the midline using electronic calipers at the time of scanning. Volume of the thyroid lobe was computed according to the following formula: thyroid height*width*depth*correction factor (0.63).Results Age-, sex-, body mass index- and smoking-adjusted heritability of the thickness of thyroid isthmus was 50% (95% confidence interval [CI], 35 to 66%). Neither left nor right thyroid volume showed additive genetic effects, but shared environments were 68% (95% CI, 48 to 80%) and 79% (95% CI, 72 to 87%), respectively. Magnitudes of monozygotic and dizygotic co-twin correlations were not substantially impacted by the correction of covariates of body mass index and smoking. Unshared environmental effects showed a moderate influence on dependent parameters (24-50%).Conclusions Our analysis support that familial factors are important for thyroid measures in a general twin population. A larger sample size is needed to show whether this is because of common environmental (e.g. intrauterine effects, regional nutrition habits, iodine supply) or genetic effects

Conspiracy theory as spatial practice: the case of the Sivas arson attack, Turkey

This article discusses the relationship between conspiratorial thinking and physical space by focusing on the ways conspiracy theories regarding political violence shape and are shaped by the environments in which it is commemorated. Conspiratorial thinking features space as a significant element, but is taken to do so mainly figuratively. In blaming external powers and foreign actors for social ills, conspiracy theorists employ the spatial metaphor of inside versus outside. In perceiving discourses of transparency as the concealment rather than revelation of mechanisms of governance, conspiracy theorists engage the trope of a façade separating the space of power’s formulations from that of its operations. Studying the case of an arson attack dating from 1990s Turkey and its recent commemorations, this article argues that space mediates conspiracy theory not just figuratively but also physically and as such serves to catalyze two of its deadliest characteristics: anonymity and non-linear causality. Attending to this mediation requires a shift of focus from what conspiracy theory is to what it does as a spatial practice

Population Stratification of a Common APOBEC Gene Deletion Polymorphism

The APOBEC3 gene family plays a role in innate cellular immunity inhibiting retroviral infection, hepatitis B virus propagation, and the retrotransposition of endogenous elements. We present a detailed sequence and population genetic analysis of a 29.5-kb common human deletion polymorphism that removes the APOBEC3B gene. We developed a PCR-based genotyping assay, characterized 1,277 human diversity samples, and found that the frequency of the deletion allele varies significantly among major continental groups (global F (ST) = 0.2843). The deletion is rare in Africans and Europeans (frequency of 0.9% and 6%), more common in East Asians and Amerindians (36.9% and 57.7%), and almost fixed in Oceanic populations (92.9%). Despite a worldwide frequency of 22.5%, analysis of data from the International HapMap Project reveals that no single existing tag single nucleotide polymorphism may serve as a surrogate for the deletion variant, emphasizing that without careful analysis its phenotypic impact may be overlooked in association studies. Application of haplotype-based tests for selection revealed potential pitfalls in the direct application of existing methods to the analysis of genomic structural variation. These data emphasize the importance of directly genotyping structural variation in association studies and of accurately resolving variant breakpoints before proceeding with more detailed population-genetic analysis

Manipulating multiple sequence alignments via MaM and WebMaM

MaM is a software tool that processes and manipulates multiple alignments of genomic sequence. MaM computes the exact location of common repeat elements, exons and unique regions within aligned genomics sequences using a variety of user identified programs, databases and/or tables. The program can extract subalignments, corresponding to these various regions of DNA to be analyzed independently or in conjunction with other elements of genomic DNA. Graphical displays further allow an assessment of sequence variation throughout these different regions of the aligned sequence, providing separate displays for their repeat, non-repeat and coding portions of genomic DNA. The program should facilitate the phylogenetic analysis and processing of different portions of genomic sequence as part of large-scale sequencing efforts. MaM source code is freely available for non-commercial use at ; and the web interface WebMaM is hosted at

Non-alignment comparison of human and high primate genomes

Compositional spectra (CS) analysis based on k-mer scoring of DNA sequences was employed in this study for dot-plot comparison of human and primate genomes. The detection of extended conserved synteny regions was based on continuous fuzzy similarity rather than on chains of discrete anchors (genes or highly conserved noncoding elements). In addition to the high correspondence found in the comparisons of whole-genome sequences, a good similarity was also found after masking gene sequences, indicating that CS analysis manages to reveal phylogenetic signal in the organization of noncoding part of the genome sequences, including repetitive DNA and the genome "dark matter". Obviously, the possibility to reveal parallel ordering depends on the signal of common ancestor sequence organization varying locally along the corresponding segments of the compared genomes. We explored two sources contributing to this signal: sequence composition (GC content) and sequence organization (abundances of k-mers in the usual A,T,G,C or purine-pyrimidine alphabets). Whole-genome comparisons based on GC distribution along the analyzed sequences indeed gives reasonable results, but combining it with k-mer abundances dramatically improves the ordering quality, indicating that compositional and organizational heterogeneity comprise complementary sources of information on evolutionary conserved similarity of genome sequences

Feed form and perch design do not interact to production performance, gastrointestinal tract traits, behaviour and welfare of laying hens reared in enriched cages

1. It was hypothesised that perch material and design may affect utility and maintenance energy demand in laying hens, affecting their feed form preferences and daily feed consumption. Accordingly, perch design and feed form on hen performance, gastrointestinal tract functions and some behavioural and welfare-related traits were studied in laying hens (ATAK-S) reared in enriched colony cages from 24 to 40 weeks of age. 2. The experiment was a 2 × 2 factorial investigating two perch materials and design (circular steel or mushroom-shaped plastic) and feed form (mash or crumble). A total of 396 hens were randomly assigned to one of the four treatment groups with nine replicates each (11 birds per replicate). 3. Except for feeding behaviour and prevalence of foot pad dermatitis at 40 weeks of age, the modification of the perch design did not have a significant effect on the traits examined. Mushroom-shaped plastic perches reduced feeding behaviour (p < 0.01) and the incidence of foot pad dermatitis at 40 weeks of age (p < 0.001). 4. Performance traits were not affected by feed form. Intake, final body weight and FCR for crumble-fed laying hens were greater than those fed mash (p < 0.01). 5. Hens fed mash had higher (p < 0.01) relative gizzard weights along with lower (p < 0.05) pH values, pancreatic chymotrypsin, amylase and lipase activities (p < 0.05), and duodenal absorption surface areas (p < 0.01). Ultimately, this gave higher protein digestibility (p < 0.05) compared to those receiving crumble. 6. In conclusion, in enriched cage rearing systems, mashed feed was preferred over crumble to efficiently maintain productive performance. Compared to circular steel, plastic mushroom-shaped perches were associated with better footpad health and welfare. © 2024 British Poultry Science Ltd

Effects of Platelet Rich Plasma and Amniotic Cell Culture Medium on Wound Healing Following Experimental Animal Tracheal Injury Model: A Comparative Study

Introduction: Prolonged inflammation after tracheal injury invariably results in a degree of stenosis. The topical application of platelet-rich plasma (PRP) and human amniotic fluid-derived cell culture medium (ACCM) have been shown to promote wound healing. The effects of PRP and amniotic cell culture medium (Gibco AmnioMAX - II ) were investigated in a rat model through morphometric, histological, and biochemical parameters. Material & Methods: Thirty-two male Sprague Dawley rats were included in the study: 4 rats provided for the preparation of PRP. Three groups of 7 rats were divided into PRP and ACCM groups, a control and a sham group respectively. A transverse incision on the ventral aspect of the third trachea spanning half of the tracheal circumference was performed. The incision was repaired with 7/0 polypropylene in the sham group. In the control group, 0.5 ml saline solution was applied on to the repaired injury site. In the other two groups, 0.5 mL PRP or ACCM were applied topically on the tracheal repair. Tissue samples were harvested 30 days after surgery for morphometric measurements and biochemical analyses for oxidative stress markers, IL-1beta, IL-6, and VEGF. Connective tissue thickness was evaluated histologically. Statistical analysis included the Mann-Whitney U and Kruskal Wallis tests. Results: A notable difference was detected (P = 0,025) in cartilage segment length measurements of the trachea between the ACCM group and the sham and control groups (P < 0.03). A significant difference was found in the analysis of TAS, TOS, and OSI values between the study groups and the control and sham groups (P < 0.005). There were also differences in IL1-beta and IL-6 levels between ACCM and PRP groups (P < 0.05). For the same parameters, the differences were significant between the PRP and, sham and control groups (P = 0,004 and P = 0,002 respectively), and between the ACCM and, sham and control groups (P = 0,003 and P = 0,002 respectively). VEGF values demonstrated a significant difference between the PRP and sham group (P = 0,002), and between ACCM and sham/control groups (p=0,002 for both), the highest VEGF value was in ACCM group while the lowest value was in the sham group. In the histological assessment of connective tissue, a significant difference was observed between ACCM and the other groups. Conclusion: Amniotic fluid-derived cell culture medium shows less oxidative stress status than the other applications. ACCM is more effective on inflammatory and angiogenetic processes. Connective tissue thickness results were consistent with those biochemical and morphologic results. Additionally, a significant difference was observed in histological data between ACCM and PRP. Overall, ACCM proved to be efficient on tracheal healing. These effects can be attributed to the abundance of growth factors in both PRP and amniotic fluid-derived cell culture medium (ACCM)

Анализ технологических решений при добыче нефти из неоднородных многопластовых залежей с высоким газосодержанием на месторождениях Западной Сибири

Objective Liver cirrhosis is considered as a premalignant state, as about 80% of hepatocellular carcinoma (HCC) is associated with liver cirrhosis. Although alpha-fetoprotein (AFP) has a high negative predictive value, its sensitivity for detecting HCC is poor. The aim of this study was to evaluate circulating endoglin (CD105) in the serum of patients with liver cirrhosis and at high risk for HCC. Methods CD105 and AFP serum concentrations were measured in 70 healthy and 94 nonliver-diseased controls and 130 patients with chronic liver diseases and HCC, respectively. Results Fifty-seven liver cirrhotic patients, 45 patients with liver cirrhosis plus HCC, 19 liver fibrosis patients and nine patients with HCC only were studied. Serum CD105 is significantly elevated in liver cirrhotic patients compared with healthy (P<0.0001) and nonliver-diseased controls (P<0.0001). Patients with liver cirrhosis and HCC show the highest CD105 concentrations being significantly elevated in comparison to liver cirrhosis (P=0.0006) and HCC only (P=0.0134). A stronger positive correlation exists between CD105 and AFP in the patient group suffering from liver cirrhosis and HCC (r=0.479, P=0.0015) than the obtained correlation between both markers in the group of patients diagnosed with liver cirrhosis alone (r=0.358, P=0.0073). The logistic regression model identified CD105 as an independent marker (P=0.0077, odds ratio 1.3). Conclusion CD105 has the potential to be a novel complementary biomarker that has some important bearing on the risk assessment for development of HCC in cirrhotic patients

The creation of new rotation arc to the rat latissimus dorsi musculo-cutaneous flap with delay procedures

BACKGROUND: Latissimus dorsi musculocutaneous flap is one of the most frequently performed reconstructive techniques in surgery. Latissimus dorsi muscle has two arcs of rotation. It is classified as type V muscle. This muscle can be elevated on the thoracodorsal artery to cover large defects in the anterior chest and also, the muscle can be elevated on the segmental vessels to cover midline defects posteriorly. The aim of this study was to create a new arc of rotation on a vertical axis for the muscle and investigate effectiveness of vascular and chemical delays on the latissimus dorsi muscle flap with an inferior pedicle in an experimental rat model. We hypothesized that the latissimus dorsi muscle would be based on inferior pedicle by delay procedures. METHODS: We tested two different types of delay: vascular and combination of vascular and chemical. We also tried to determine how many days of "delay" can elicit beneficial effects of vascular and combination delays in an inferior pedicled latissimus dorsi musculocutaneous flap. To accomplish this, 48 male Sprague-Dawley rats were randomly subjected to vascular or combination delay (vascular and chemical). In addition, one ear of each rat was assigned into a delay procedure and the other ear was used as a control. Results were evaluated macroscopically, and micro-angiography and histological examinations were also performed. As a result, there was a significant difference in viable flap areas between vascular delay alone and control groups (p < 0.05). RESULTS: The higher rate of flap viability was obtained in seven-day vascular delay alone. However, there was no significant difference in the viability between seven-day vascular delay and five-day vascular delay (p < 0.05), so the earliest time when the flap viability could be obtained was at five days. The rate of flap viability was significantly higher in the vascular delay combined with chemical delay than the control group (p < 0.05). CONCLUSION: The combination of vascular and chemical delays increased the rate of viability. Nevertheless, there was no significant difference between vascular delay alone and combination of vascular and chemical delays. Chemical delay did not significantly decrease the delay period. Better histological and microangiographical results were achieved in delay groups compared to control groups. We concluded that the arch of the latissimus dorsi musculocutaneous flap can be changed and the flap can be used for various purposes with the delay procedures