bluuebunny/crossref_metadata_2025 huggingface dataset:
Villi, Villi Everywhere: Biological Structures, Surface Area, & Proportional Thinking
Authors: Westrich Kathleen , Berg Craig
Published: March 2011

We present an activity that models the teaching of content knowledge that transfers to many areas of the life sciences and simultaneously targets growth in cognitive development. The activity provides students with concrete objects and thinking experiences that facilitate an understanding of how surface area, in the context of biological systems, is a critical and common factor in life-supporting functions. Alveolus structure and gas exchange in the lungs, nephron structure and water retention in the kidneys, villus structure and nutrient absorption in the small intestine, and root-hair structure and nutrient absorption in plants are all biological examples in which surface area plays a key role in living things. In addition, this activity incorporates components that engage students in thinking about proportional reasoning, as many students lack the proportional thinking skills needed to fully understand this structure/function relationship or to transfer the relationship to a new, but related, situation.
Management of hyperthyroidism during pregnancy and lactation
Authors: Azizi Fereidoun , Amouzegar Atieh
Published: March 2011

Introduction

Poorly treated or untreated maternal overt hyperthyroidism may affect pregnancy outcome. Fetal and neonatal hypo- or hyper-thyroidism and neonatal central hypothyroidism may complicate health issues during intrauterine and neonatal periods.

Aim

To review articles related to appropriate management of hyperthyroidism during pregnancy and lactation.

Methods

A literature review was performed using MEDLINE with the terms ‘hyperthyroidism and pregnancy’, ‘antithyroid drugs and pregnancy’, ‘radioiodine and pregnancy’, ‘hyperthyroidism and lactation’, and ‘antithyroid drugs and lactation’, both separately and in conjunction with the terms ‘fetus’ and ‘maternal.’

Results

Antithyroid drugs are the main therapy for maternal hyperthyroidism. Both methimazole (MMI) and propylthiouracil (PTU) may be used during pregnancy; however, PTU is preferred in the first trimester and should be replaced by MMI after this trimester. Choanal and esophageal atresia of fetus in MMI-treated and maternal hepatotoxicity in PTU-treated pregnancies are of utmost concern. Maintaining free thyroxine concentration in the upper one-third of each trimester-specific reference interval denotes success of therapy. MMI is the mainstay of the treatment of post partum hyperthyroidism, in particular during lactation.

Conclusion

Management of hyperthyroidism during pregnancy and lactation requires special considerations and should be carefully implemented to avoid any adverse effects on the mother, fetus, and neonate.
Coxsackie and adenovirus receptor is a target and a mediator of estrogen action in breast cancer
Authors: Vindrieux David , Le Corre Ludovic , Hsieh Jer-Tsong , Métivier Raphaël , Escobar Pauline , Caicedo Andrès , Brigitte Madly , Lazennec Gwendal
Published: March 2011

The involvement of the coxsackie and adenovirus receptor (CAR), an adhesion molecule known to be the main determinant of adenovirus transduction of the cells, in cancer is currently under investigation. Recent reports suggest that CAR levels are elevated in breast cancer, and this may have an impact on its use as means of delivery for gene therapy. In this study, we show that estradiol (E2) treatment of the estrogen receptor (ER)-positive breast cancer cell MCF-7 increases CAR levels and, in turn, enhances adenoviral transduction. Employing the transfection of CAR promoters in breast cancer cells, we show that this regulation of CAR expression occurs at the transcriptional level. In addition, and by chromatin immunoprecipitation, we have identified a crucial region of CAR promoter that controls E2 responsiveness of CAR gene through the recruitment of ER. Moreover, utilizing CAR antibodies or CAR silencing by RNA interference repressed the estrogen-dependent growth of breast cancer cells, whereas the stable expression of CAR in MCF-7 or MDA-MB-231 cells led to an increased proliferation. Altogether, our data suggest that CAR is a novel estrogen-responsive gene, which is involved in the E2-dependent proliferation of breast cancer cells.
A macrophage and theca cell-enriched stromal cell population influences growth and survival of immature murine follicles in vitro
Authors: Tingen Candace M , Kiesewetter Sarah E , Jozefik Jennifer , Thomas Cristina , Tagler David , Shea Lonnie , Woodruff Teresa K
Published: March 2011

Innovations inin vitroovarian follicle culture have revolutionized the field of fertility preservation, but the successful culturing of isolated primary and small secondary follicles remains difficult. Herein, we describe a revised 3D culture system that uses a feeder layer of ovarian stromal cells to support early follicle development. This culture system allows significantly improved primary and early secondary follicle growth and survival. The stromal cells, consisting mostly of thecal cells and ovarian macrophages, recapitulate thein vivoconditions of these small follicles and increase the production of androgens and cytokines missing from stromal cell-free culture conditions. These results demonstrate that small follicles have a stage-specific reliance on the ovarian environment, and that growth and survival can be improvedin vitrothrough a milieu created by pre-pubertal ovarian stromal cell co-culture.
Social psychological determinants of the formation of medical students’ professional identity. Possibilities of development
Authors: Csörsz Ilona
Published: March 2011

Systematic observations regarding techniques of medical career-socialization has hardly ever appeared in Hungarian technical literature yet. Focusing on the need for practical medical training the author elaborated a career-socialization program consisting of a three-level, three-branch training technique. This consisted of a Junior Bálint-group, an imaginative visualization technique, and an expressive, drama-pedagogical working method completed with a projective technique. This career-socialization program focuses on the physician’s personality, capability-expansion in relationship management, and practicing a set of professional behavior-roles. During the empirical observations connected to the work the author examined medical students’ patient-representation, their relation to the patients, and the development of the physician’s professional character. Within the frames of this three-level, three-branch training technique program it enables us to observe which training technique is able to reveal all those psychological qualities that can contribute to the conformation of the representations, thus to the process of career-socialization in the most effective way. The content-analyses of the cases of Junior Bálint-groups (n = 60) revealed that the most frequent problems are fear of intimacy, of bodily contact, communication with patients in a chronic or terminal state, and the fear of medical practice. The content-analyses of imaginary patient-images (n = 62) with Rorschach-signs confirmed that the psychological burdens mentioned above are the most serious problems for medical students. The process-, and content-analyses of drama-games, the integrative healing contact training groups (n = 74) showed that group work primarily intensifies the relationship responsiveness, the ability to adopt the other’s (the patient’s) viewpoints, and enables an involuntary and distressless identification with the patient and the physician, both agents in the healing relationship. It is the drama-game that gives significant support to experience the physician- patient relationship in a high quality level. In the next phase the author tested the short story used for the drama-game and its projective contents on a sample of medical and psychology students (n = 313). For the statistical analysis the SPSS and the LEM program-packets were applied. Statistical methods included variance analysis, chi-square test and log-linear analysis. The vast similarity of the projective contents appearing in the survey questionnaire and in the drama-group verified that the chosen short story as a projective surface is suitable for recalling the students’ typical stereotypes and representations related to diseases, patients, healing experts and therapeutic situations. The drama-group focused on the realization of these stereotypical representations, and also on experiencing and forming the students’ emotional relations to them. Orv. Hetil., 2011, 152, 475–480.
What research should be done and why? Four competing visions among ecologists
Authors: Neff Mark W
Published: March 2011

Information we collect about our planet depends, in part, on the questions scientists ask regarding the natural world. Asking other questions might lead to different innovations and alternative understandings of policy problems and their potential solutions. With a seemingly infinite number of potential study subjects but limited resources with which to study them, why have we chosen to focus on the topics that we have? Here, I present a Q‐method study that explores ecologists' thought processes as they evaluate the merits of potential research topics. The participants, ecologists attending the Ecological Society of America's 2008 Annual Meeting, nominally agreed with one another that their discipline should contribute to solving environmental problems, but they interpreted that goal differently. This study uncovers four competing visions that ecologists have for their discipline. On the basis of these findings, I contend that ecology might be more effective in informing policy if priority setting were a more deliberative process and open to insights from individuals and institutions outside of ecology.
Impact of a Short Pre-Freshman Program on Retention
Authors: Wischusen Sheri M. , Wischusen E. William , Pomarico Steven M.
Published: March 2011

The Biology Intensive Orientation for Students (BIOS) Program at Louisiana State University was designed to increase the success of incoming freshman biology majors in the first course in their major. The program combined content lectures and examinations for BIOL 1201–Introductory Biology for Science Majors, the first course in their major, as well as learning styles assessments and informational sessions intended to provide the students with a preview of the requirements of biology, and the pace of college. BIOS participants showed increased success and retention in the biology major, and remained on track to graduate in 4 years at a significantly higher rate than students who did not participate in BIOS.
The Retention Dilemma: Effectively Reaching the First-Year University Student
Authors: Copeland Kelly J. , Levesque-Bristol Chantal
Published: March 2011

Student success results from positive learning environments which strive to meet the basic psychological needs of students, foster self-determined forms of motivation, and cultivate learning outcomes such as knowledge transfer, meta-cognition, and engagement. Low first-year student retention rates lead many universities to assess factors associated with student success. By surveying the needs, interests, and goals of 390 first-year students at Missouri State University, we proposed and tested a conceptual model using group differences and structural equation modeling. Results supported our general hypothesis that certain antecedents (e.g., expectations, teachers' influences) and motivational processes can lead to enhanced learning outcomes. Results suggested that autonomy supportive environments allow the basic need for perceived competence to more successfully impact self-determined forms of motivation. Suggestions are made for institutions to focus on creating positive, autonomy supportive learning environments in which to improve student satisfaction and success and therefore lead to better first-year student retention.
Losing Contact with One'S Unborn Baby—Mothers' Experiences Prior to Receiving News That Their Baby Has Died in Utero
Authors: Malm M.-C. , Lindgren H. , Rådestad I.
Published: March 2011

Background:

A change in the pattern of movement of her unborn baby could be indicative that the baby might die.

Aim:

To study mothers' experiences during the time prior to receiving news that their baby has died.

Method:

Interviews with 26 mothers.

Results:

Premonition that something had happened to their baby, a sense based on a lack of movements were experienced. Six categories describe the mother's insight that the baby's life was threatened: not feeling in touch with their baby; worry' feeling something is wrong; not understanding the unbelievable; wanting information; and being certain that their baby had died. The overarching theme “There is something wrong” was formulated.

Conclusion:

The mother could not understand the unbelievable: that the baby had died in utero.

Implications:

Mother's should be cautioned to trust their insights and seek medical advice if they are concerned over the lack of movement from the unborn baby.
Quality Insights of University Students on Dying, Death, and Death Education—A Preliminary Study in Hong Kong
Authors: Mak Mui Hing June
Published: March 2011

Death is a subject seldom studied in school and often misunderstood and feared by many people. Children often learn about death from their family and mass media. From the literature review on dying, death, and death education, it may be concluded that people are generally ignorant about the issues of death and dying. There is a need to investigate what young people, such as university students, know about death and dying, and their attitudes toward them. Eight university students were recruited for this study. Most participants have had death experiences. They seldom talked about death and loss. Some of these experiences were quite pleasant but some of them were not. Most participants addressed the need to have “life and death” education in schools at their young age. Such a need is further supported by the incidents of two participants who attempted suicide unsuccessfully when they encountered a life problem which they could not solve.
Equity Value Implications of Lease Accounting
Authors: Boatsman James , Dong Xiaobo
Published: March 2011

SYNOPSIS: The literature exhibits a long tradition of attention to the financial statement effects of accounting for operating leases. For the most part, that attention has focused on what are commonly viewed as errors in operating assets, deferred tax liabilities, debt, stockholders’ equity, and net income that, if not properly corrected, can lead to errors in financial statement analysis. There has been, at least, an implied effect of such financial statement analysis errors on estimated equity value. What has been lacking is a discussion of the precise nature of how the errors may, or may not, translate into errors in estimating equity value. We bring clarity to this matter through an example in which a nai¨ve reliance on financial statements unadjusted for the errors in accounting for operating leases has no effect on equity value estimated with three popular equity valuation models. We then discuss prior empirical evidence suggesting that the critical aspect of the example, namely the cost of equity capital is exogenously determined, is expected to be present in many practical applications. In short, lease accounting is often not a matter of consequence in the context of estimating equity value.
The Impact of Regulation on the U.S. Nonprofit Sector: Initial Evidence from the Nonprofit Integrity Act of 2004
Authors: Neely Daniel G.
Published: March 2011

SYNOPSIS: The early 2000s revealed a series of high-profile financial frauds in the corporate and nonprofit sectors. In response to several of these financial scandals, California passed the Nonprofit Integrity Act (NIA) of 2004. This seminal piece of governance regulation sought to increase financial transparency and mitigate fundraising abuses by California charitable organizations. This study examines the characteristics of California charitable organizations before and after the Act to understand the initial impact the Act had on nonprofit organizations. Key findings from the study include limited reported improvement in financial reporting quality and an increase in accounting fees following the implementation of the Act. California nonprofits subject to the Act’s provisions did exhibit an increase in executive compensation following the implementation of the Act; however, the increase was less than that exhibited by the population of nonprofits during the same time period. Overall, the results of this study suggest that the initial impact of regulations similar to the NIA is greatest for organizations that did not previously have a financial statement audit.
Are Dividends Associated with the Quality of Earnings?
Authors: Tong Yen H. , Miao Bin
Published: March 2011

SYNOPSIS: We examine whether dividend paying status is associated with the quality of earnings. We find dividend paying status is associated with (1) lower absolute values of discretionary accruals; (2) lower standard deviation and absolute magnitude of the errors associated with the mapping of accruals into cash flows; and (3) more value relevant earnings. We also find evidence that the positive association between dividend paying status and earnings quality is stronger (weaker) when the size of dividend payouts is larger (smaller). Overall, our results suggest dividend paying status is indicative of firms’ earnings quality.
Audit Fees after Remediation of Internal Control Weaknesses
Authors: Munsif Vishal , Raghunandan K. , Rama Dasaratha V. , Singhvi Meghna
Published: March 2011

SYNOPSIS: In this study, we examine audit fees for SEC registrants that remediate previously disclosed material weaknesses in internal control. We find that remediating firms have lower audit fees when compared to firms that continue to report material weaknesses in internal control. However, the remediating firms continue to pay, in the year of remediation as well as one and two years subsequent to remediation, a significant audit fee premium compared to firms that have clean Section 404 reports in each of the first four years. Firms that had an adverse Section 404 report only in the first year, but remediated the problems in year two and had clean Section 404 reports in years three and four, pay an audit fee premium of 32 (21) percent in the third (fourth) year when compared to firms that had clean Section 404 reports in each of the first four years. The results, thus, suggest that audit fees are “sticky” for firms that have material weaknesses in internal controls over financial reporting, and suggest some interesting questions for future research.
Parasitic infections and pregnancy complications
Authors: Pavlinová J. , Kinčeková J. , Ostró A. , Saksun L. , Vasilková Z. , Königová A.
Published: March 2011

Infections of various aetiology during pregnancy present a serious risk factor that can lead to abortion, premature birth, stillbirth, birth of newborn with genetic developmental defects, or seemingly healthy infant that may develop symptoms later in life. A total of 530 sera of patients from gynaecology departments were examined for antibodies against Toxoplasma gondii, Toxocara spp. and Listeria monocytogenes using ELISA (IgG, IgM). In women with habitual abortions we determined up to 42.1 % seroprevalence of IgG antibodies against T. gondii. The prevalence of antibodies was statistically significant (p < 0.0004) when compared to control group (25.1 %). In the patients diagnosed with sterility the prevalence of antibodies (26.3 %) was similar to that of control group. The prevalence of antibodies against Toxocara spp. (5.5 %) and Listeria monocytogenes (2.3 %) in patients with habitual abortions were similar to those of women in the general population.
Surface of the filarial parasite Setaria digitata and the structural changes on treatment with Triton X-100
Authors: Madathiparambil M. , Kavitha Raj N. , Linda J. , Kaleysa Raj R.
Published: March 2011

Setaria digitata, a bovine filarial parasite is used as a laboratory model for filariasis. The studies showed that considerable amount of biochemically and immunologically active materials are present on the surface of the parasite. The effect of Triton X-100 on the surface of the parasite, when it is used to separate the surface associated materials, is not known. Treatment with Triton X-100 enhances the amount of ES protein released into the medium. The electron microscopic study of S. digitata wall showed that structure of the surface is similar to that of W. bancrofti. There are striations, annulations and button like bosses on the filarial surface. On treatment with Triton X-100 the electron dense cloudy layer on the surface was disappeared. The surface appeared to be suitable for hosting secreted molecules on the surface.
The tapeworm Paradilepis scolecina (Rudolphi, 1819) (Cestoda: Cyclophyllidea) invasion in Great Cormorant [Phalacrocorax carbo sinensis (Blumenbach, 1798)] from the breeding colony in Lake Selment Wielki (northern Poland)
Authors: Dziekońska-Rynko J. , Dzika E.
Published: March 2011

The intensity and extensity of infestation of cormorants (Phalacocorax carbo sinensis) from a colony in Lake Selment Wielki with the tapeworm Paradilepis scolecina (Rudolphi, 1819) was examined. The cormorants were shot in April, August and October 2006 and in August and September 2007. The extensity of infection in all the cormorants under study was very high — even reaching 100 %. The highest intensity of infestation was found in the birds shot in August — 4697 tapeworms per bird in 2006 and 2562 in 2007. The intensity of infestation in the birds which were shot in autumn was less than one-tenth of that found in the birds shot in summer. The lowest intensity of infestation was found in the spring of 2006 — 61 tapeworms per bird.
Infection with Crenosoma vulpis lungworm in a dog in the Czech Republic
Authors: Husník R. , Sloboda M. , Kovaříková S. , Koudela B.
Published: March 2011

A one-year-old female Shetland Sheepdog was presented with chronic cough. The patient exhibited tachypnea and moist cough, bronchoscopic examination revealed a hyperaemic trachea and mucopurulent exudate affecting the lower bronchi. Nematode parasites were observed during bronchoscopy and were collected by bronchoalveolar lavage. Microscopic examination of the collected fluid confirmed C. vulpis infection; L1 larvae were found in during coproscopy. Although other cases of canine C. vulpis infection have been previously recorded in Europe, the case reported herein is the first in a dog from Czech Republic.
The Relationship of School Structure and Support to Suspension Rates for Black and White High School Students
Authors: Gregory Anne , Cornell Dewey , Fan Xitao
Published: March 2011

This study examined the relationship between structure and support in the high school climate and suspension rates in a statewide sample of 199 schools. School climate surveys completed by 5,035 ninth grade students measured characteristics of authoritative schools, defined as highly supportive, yet highly structured with academic and behavioral expectations. Multivariate analyses showed that schools low on characteristics of an authoritative school had the highest schoolwide suspension rates for Black and White students after statistically controlling for school demographics. Furthermore, schools low on both structure and support had the largest racial discipline gaps. These findings highlight the characteristics of risky settings that may not meet the developmental needs of adolescents and may contribute to disproportionate disciplinary outcomes for Black students.
Yamashita's Post-National Spaces: “It All Comes Together in Los Angeles”
Authors: Mermann-Jozwiak Elisabeth
Published: March 2011

Abstract:

This essay explores Karen Fei Yamashita's representation of Los Angeles, not as a hub of multiculturalism, but as a nodal point that connects Asia, Central and South America, and Africa. Tropic of Orange cleverly depicts the roots and routes of transnational exchanges of labour and trade, and, in the process, shows the transformations of the local environment through these global contacts. The novel further conducts a spatial archaeology to highlight spatial injustices, focusing on the various (im)migrant populations that occupy a single city neighbourhood over time, regulations that restrict their access, and the unequal distribution of resources and development of infrastructures.
American Studies in Review: Killer Apps
Authors: Hamilton Geoff
Published: March 2011

Abstract:

This review examines David Schmid's Natural Born Celebrities: Serial Killers in American Culture and Mark Seltzer's True Crime: Observations on Modernity and suggests that they are both significant contributions to recent scholarship on the importance of violent criminality to contemporary cultural life. While Schmid's focus is the strange celebrity of the serial killer and the ways this figure has forwarded diverse ideological and commercial interests, Seltzer posits crime narratives as revealing models for contemporary modes of sociality and belief.
“The Revolution Will Not Be Televised”: Community Activism and the Black Panther Party, 1966–1971
Authors: Kirkby Ryan J.
Published: March 2011

Abstract:

This article examines the Black Panther Party's community activism from 1966 to 1971, with two aims in mind. First, it provides an overview of the numerous “survival programs” organized by the party in human sustenance, health care, education, and criminal justice, detailing their revolutionary intentions. Second, and more importantly, it challenges scholars to start considering ways in which community activism and revolutionary violence operated in tandem as part of the same strategy for Black liberation. In this way, it emphasizes the necessity to move beyond stagnant characterizations of the party as either humanitarian do-gooders or violent street toughs to construct a more complex interpretation of the BPP's legacy.
The Little Black School House: Revealing the Histories of Canada's Segregated Schools— A Conversation with Sylvia Hamilton
Authors: Howard Brianne , Smith Sarah E.K.
Published: March 2011

Abstract:

Segregated schools are a widely documented component of American history. Conversely, in Canada, provincially legislated segregation of Black Canadians has not been fully acknowledged. This historical amnesia raises numerous questions about the construction of Black experiences in both states. This interview examines Sylvia Hamilton's documentary The Little Black School House (2007), which explores the past as a means to contribute to the ongoing vitality of Black communities. Our discussion places this film within the historical context of legislated segregation in Canada and the United States, drawing attention to histories that have been largely absent within the dominant Canadian historical narrative.
He “coulda been a contender” for Miss America: Feminizing Brando in On the Waterfront
Authors: Schuyler Michael T.
Published: March 2011

Abstract:

This alternative reading of On the Waterfront discusses how the film presents a feminized version of Marlon Brando's character, Terry Malloy. Then, it puts this portrayal into context, suggesting that director Elia Kazan wants to portray Terry as American only once this character sheds his womanly trappings and undergoes a rebirth as an “acceptable” bastion of masculinity. After all, in Waterfront's narrative, which allegorizes Kazan's decision to testify in front of the House Un-American Activities Committee, Terry serves as a surrogate for the director; therefore, Kazan wants to equate Terry's eventual return to masculinity with his own choice to name names. And, in the view of Kazan, “manly men” best represent America.
Study of Erosion-Corrosion of Stainless Steel, Brass and Aluminum by Open Circuit Potential Measurements
Authors: Kabir Kazi Bayzid , Mahmud Iqbal
Published: March 2011

The PDF for this article was replaced on 16/05/2011 with minor editorial changes. - EditorInfluence of flow on corrosion behavior of stainless steel, brass and aluminum was studied using electrochemical measurement techniques. Flow effect was identified by comparing erosion-corrosion with pure corrosion studies. For this purpose, open circuit potential (OCP) measurements were performed in both quiescent and flow conditions. OCP transient for the metals/alloys (stainless steel, brass and aluminum) indicated the nature and extent of corrosion on the sample by the environment (seawater and sodium carbonate). Three distinct type of curves were found for all metal-environment combinations. Increasing OCP indicated noble metal behavior while decrease in OCP indicated corrosion of material in the exposed environment. Directional shift in the OCP indicated changes in the surface phenomena. Hence, shape of these curves provides information about the extent of metal environment interaction. Experimental observations showed the applicability of open circuit measurements for on-line corrosion monitoring. Keywords open circuit potential; erosion-corrosion; electrochemical measurements; stainless steel; brass; aluminum. DOI: 10.3329/jce.v25i0.7234Journal of Chemical Engineering, IEB Vol. ChE. 25, No. 1, December 2010 pp.13-17
Identification of Occupational Injury among the Workers of Selected Cement Industries in Bangladesh - A Case Study
Authors: Iqbal Salma A , Iqbal Mohammed , Taufiq Md Zubair , Ahmed Md Shamim
Published: March 2011

The paper deals with the identification of occupational injury among workers in selected cement industries of Bangladesh. In this regard, the case study was conducted to extract the overall scenario of the occupational injury. Injury data were collected by using questionnaires from the workers as well as supervisors of four cement industries. The data collected were analyzed in terms of different variables, such as body parts, agent of accident, experience, age, skill, and type of injury. Pareto analysis was then applied to find a pattern of occupational injury among the workers. The study disclosed that arm, leg, hand finger, Eye and head covered 82.81% of total i njury frequency, 76.56% of total injuries by welding, bucket elevator, belt conveyor and weight lifting, low experienced and high experienced workers have 84.38% of total injury frequency, age group of 21-25 and 51-55 have the maximum injury frequency, 78.13% injury occurred by highly skilled and unskilled workers and 79.1% of total injury is temporary disable type injury. The paper also provides specific suggestions followed by some action plans. Keywords injury; accident; workers; safety; cement industry; training. DOI: 10.3329/jce.v25i0.7236Journal of Chemical Engineering, IEB Vol. ChE. 25, No. 1, December 2010 pp.22-28
Endocrine Distruction Chemicals (EDCs) Degradation in an Advanced Oznone Membrane Reactor - Experimental & Modelling Study
Authors: Islam MS , Blondy A , Yeung KL , Choudhury MAAS , Julbe A , Ayral A , Heng SH , Schrotter JC
Published: March 2011

A study of ozonolysis degradation kinetics of EDCs in two phase gas-liquid system has been performed in a semibatch reactor observing Total Organic Carbon (TOC) degradation. TOC degradation alone may not be a sufficient parameter because multiple/complex kinetic concept is needed. This has been accomplished with experimental work. Reaction perturbed evolution and decay of the initial substance and its degradation by-products have been observed based on Glasser-Hildebrandt concept. TOC degradation and multiple/complex reaction kinetic parameters have been determined from percentage TOC consumption and HPLC area response rationalization based on carbon balance. These kinetic information have been incorporated to model and simulate ozone membrane reactor system using (i) mass balance approach and (ii) widely used continuity equation. The derived model answers the values of the characteristic parameters such as efficiency, molecular weight cut -off and enhancement for EDCs remediation in ozone membrane reactor. Keywords complex kinetic; Membrane reactor modeling; Dynamic simulation; Ozonolysis; Enhancement factor. DOI: 10.3329/jce.v25i0.7238Journal of Chemical Engineering, IEB Vol. ChE. 25, No. 1, December 2010 pp.43-55
A Study of Polystyrene-Metal Powder Conductive Composites
Authors: Iqbal MZ , Mamoor GM , Bashir Tariq , Irfan MS , Manzoor MB
Published: March 2011

Conductive polymer composites were prepared from polystyrene as the base material and utilizing different metallic fillers by melt processing technique using a Brabender ® plasticorder at 230°C and 120 RPM spindle speed. Different fillers used include nickel powder, carbon black, Iron and copper powders of one micron sizes. Samples for tensile, thermal and resistivity testing were prepared from hydraulic press under 220 bar pressure, at 220°C for 5 minutes and then cooling to atmospheric temperature. Iron based polystyrene composite showed good mechanical properties and nickel based composite showed better thermal and conductive properties. Three kinds of treating agents were used to modify iron which includes wax, stearic acid and acetic acid. Iron treated with acetic acid composites showed improvement in electrical and mechanical properties. This improvement was attributed to the chemical linkage established between acetic acid and polystyrene at the processing temperatures. Keywords conductive composite; fillers; polystyrene; metal DOI: 10.3329/jce.v25i0.7240Journal of Chemical Engineering, IEB Vol. ChE. 25, No. 1, December 2010 pp.61-64
Cancer Stem Cell Radioresistance and Enrichment: Where Frontline Radiation Therapy May Fail in Lung and Esophageal Cancers
Authors: Nguyen Giang Huong , Murph Mandi M. , Chang Joe Y.
Published: March 2011

Many studies have highlighted the role cancer stem cells (CSC) play in the development and progression of various types of cancer including lung and esophageal cancer. More recently, it has been proposed that the presence of CSCs affects treatment efficacy and patient prognosis. In reviewing this new area of cancer biology, we will give an overview of the current literature regarding lung and esophageal CSCs and radioresistance of CSC, and discuss the potential therapeutic applications of these findings.
Separation and Purification of Sulforaphane from Broccoli by Solid Phase Extraction
Authors: Han Dandan , Row Kyung Ho
Published: March 2011

A simple solid-phase extraction (SPE) method for the determination of sulforaphane in broccoli has been developed. The optimal conditions were found to be use of a silica SPE cartridge, and ethyl acetate and dichloromethane as washing and eluting solvents, respectively, which could eliminate interferences originating from the broccoli matrix. The extracts were sufficiently clean to be directly injected into high-performance liquid chromatography (HPLC) for further chromatographic analysis. Good linearity was obtained from 0.05 to 200 μg/mL (r = 0.998) for sulforaphane with the relative standard deviations less than 3.6%. The mean recoveries of sulforaphane from broccoli were more than 90.8% and the detection limit (S/N = 3:1) was 0.02 μg/mL. The SPE method provides a higher yield of sulforaphane from crude extracts compared to conventional liquid-liquid extraction.
Changes of Constituents and Activity to Apoptosis and Cell Cycle During Fermentation of Tea
Authors: Zhao Hang , Zhang Min , Zhao Lu , Ge Ya-kun , Sheng Jun , Shi Wei
Published: March 2011

Tea is believed to be beneficial for health, and the effects of the fermentation process on its contributions to apoptosis and cell cycle arrest of gastric cancer cells have not been completely investigated. In this study, the chemical components in green tea, black tea and pu-erh tea aqueous extracts were analyzed and compared. The polysaccharide and caffeine levels were substantially higher in the fermented black tea and pu-erh tea, while the polyphenol level was higher in the unfermented green tea. Hence, a treatment of tea aqueous extract and the components, which are emerging as promising anticancer agents, were pursued to determine whether this treatment could lead to enhance apoptosis and cell cycle arrest. In the human gastric cancer cell line SGC-7901, the cell viability and flow cytometry analysis for apoptotic cells indicated effects in a dose-dependent inhibition manner for the three tea treatment groups. The apoptosis rates were found to be elevated after 48 h of treatment with 31.2, 125, and 500 μg/mL of green tea extract, the higher catechins content may be involved in the mechanism. Cell cycle was arrested in S phase in the fermented black tea and pu-erh tea, and the populations were significantly decreased in G2/M phases, possibly due to the oxidation of tea polyphenols, which causes an increase of theabrownins. CCC-HEL-1 normal cells were not sensitive to tea extract. These findings suggest that the fermentation process causes changes of the compounds which might be involved in the changes of cell proliferation inhibition, apoptosis induction and cell cycle arrest.
RNA Detection in Live Bacterial Cells Using Fluorescent Protein Complementation Triggered by Interaction of Two RNA Aptamers with Two RNA-Binding Peptides
Authors: Yiu Hung-Wei , Demidov Vadim V. , Toran Paul , Cantor Charles R. , Broude Natalia E.
Published: March 2011

Many genetic and infectious diseases can be targeted at the RNA level as RNA is more accessible than DNA. We seek to develop new approaches for detection and tracking RNA in live cells, which is necessary for RNA-based diagnostics and therapy. We recently described a method for RNA visualization in live bacterial cells based on fluorescent protein complementation [1-3]. The RNA is tagged with an RNA aptamer that binds an RNA-binding protein with high affinity. This RNA-binding protein is expressed as two split fragments fused to the fragments of a split fluorescent protein. In the presence of RNA the fragments of the RNA-binding protein bind the aptamer and bring together the fragments of the fluorescent protein, which results in its re-assembly and fluorescence development [1-3]. Here we describe a new version of the RNA labeling method where fluorescent protein complementation is triggered by paired interactions of two different closely-positioned RNA aptamers with two different RNA-binding viral peptides. The new method, which has been developed in bacteria as a model system, uses a smaller ribonucleoprotein complementation complex, as compared with the method using split RNA-binding protein, and it can potentially be applied to a broad variety of RNA targets in both prokaryotic and eukaryotic cells. We also describe experiments exploring background fluorescence in these RNA detection systems and conditions that improve the signal-to-background ratio.
An Efficient Transmission Power Control Scheme for Temperature Variation in Wireless Sensor Networks
Authors: Lee Jungwook , Chung Kwangsue
Published: March 2011

Wireless sensor networks collect data from several nodes dispersed at remote sites. Sensor nodes can be installed in harsh environments such as deserts, cities, and indoors, where the link quality changes considerably over time. Particularly, changes in transmission power may be caused by temperature, humidity, and other factors. In order to compensate for link quality changes, existing schemes detect the link quality changes between nodes and control transmission power through a series of feedback processes, but these approaches can cause heavy overhead with the additional control packets needed. In this paper, the change of the link quality according to temperature is examined through empirical experimentation. A new power control scheme combining both temperature-aware link quality compensation and a closed-loop feedback process to adapt to link quality changes is proposed. We prove that the proposed scheme effectively adapts the transmission power to the changing link quality with less control overhead and energy consumption.
Optimization of Sensing and Feedback Control for Vibration/Flutter of Rotating Disk by PZT Actuators via Air Coupled Pressure
Authors: Yan Tianhong , Xu Xinsheng , Han Jianqiang , Lin Rongming , Ju Bingfeng , Li Qing
Published: March 2011

In this paper, a feedback control mechanism and its optimization for rotating disk vibration/flutter via changes of air-coupled pressure generated using piezoelectric patch actuators are studied. A thin disk rotates in an enclosure, which is equipped with a feedback control loop consisting of a micro-sensor, a signal processor, a power amplifier, and several piezoelectric (PZT) actuator patches distributed on the cover of the enclosure. The actuator patches are mounted on the inner or the outer surfaces of the enclosure to produce necessary control force required through the airflow around the disk. The control mechanism for rotating disk flutter using enclosure surfaces bonded with sensors and piezoelectric actuators is thoroughly studied through analytical simulations. The sensor output is used to determine the amount of input to the actuator for controlling the response of the disk in a closed loop configuration. The dynamic stability of the disk-enclosure system, together with the feedback control loop, is analyzed as a complex eigenvalue problem, which is solved using Galerkin’s discretization procedure. The results show that the disk flutter can be reduced effectively with proper configurations of the control gain and the phase shift through the actuations of PZT patches. The effectiveness of different feedback control methods in altering system characteristics and system response has been investigated. The control capability, in terms of control gain, phase shift, and especially the physical configuration of actuator patches, are also evaluated by calculating the complex eigenvalues and the maximum displacement produced by the actuators. To achieve a optimal control performance, sizes, positions and shapes of PZT patches used need to be optimized and such optimization has been achieved through numerical simulations.
Superhydrophobic surfaces of the water bugNotonecta glauca: a model for friction reduction and air retention
Authors: Ditsche-Kuru Petra , Schneider Erik S , Melskotte Jan-Erik , Brede Martin , Leder Alfred , Barthlott Wilhelm
Published: March 2011

Superhydrophobic surfaces of plants and animals are of great interest for biomimetic applications. Whereas the self-cleaning properties of superhydrophobic surfaces have been extensively investigated, their ability to retain an air film while submerged under water has not, in the past, received much attention. Nevertheless, air retaining surfaces are of great economic and ecological interest because an air film can reduce friction of solid bodies sliding through the water. This opens perspectives for biomimetic applications such as low friction fluid transport or friction reduction on ship hulls. For such applications the durability of the air film is most important. While the air film on most superhydrophobic surfaces usually lasts no longer than a few days, a few semi-aquatic plants and insects are able to hold an air film over a longer time period. Currently, we found high air film persistence under hydrostatic conditions for the elytra of the backswimmerNotonecta glaucawhich we therefore have chosen for further investigations. In this study, we compare the micro- and nanostructure of selected body parts (sternites, upper side of elytra, underside of elytra) in reference to their air retaining properties. Our investigations demonstrate outstanding air film persistence of the upper side of the elytra ofNotonecta glaucaunder hydrostatic and hydrodynamic conditions. This hierarchically structured surface was able to hold a complete air film under hydrostatic conditions for longer than 130 days while on other body parts with simple structures the air film showed gaps (underside of elytra) or even vanished completely after a few days (sternites). Moreover, the upper side of the elytra was able to keep an air film up to flow velocities of 5 m/s. Obviously the complex surface structure with tiny dense microtrichia and two types of larger specially shaped setae is relevant for this outstanding ability. Besides high air film persistence, the observation of a considerable fluid velocity directly at the air–water interface indicates the ability to reduce friction significantly. The combination of these two abilities makes these hierarchically structured surfaces extremely interesting as a biomimetic model for low friction fluid transport or drag reduction on ship hulls.
Le rôle « instrument » en question
Authors: Van de Velde Danièle
Published: March 2011

Résumé Le propos de ce travail est d’abord de rappeler certains travaux précédents selon lesquels un nom d’instrument en position de sujet peut souvent simplement être interprété comme agent, à condition que l’instrument se trouve, pour une raison ou pour une autre, doté d’une force. La partie originale du travail comporte deux volets : l’un concerne les cas où l’interprétation agentive n’est pas possible. Il est montré qu’alors le nom d’instrument sujet se présente comme « possesseur » d’une propriété – cas d’ailleurs non isolé puisqu’on le retrouve avec les verbes de mouvement. Ainsi, parallèlement à ces ciseaux coupent le papier = sont tels qu’ils permettent de couper le papier , on a cette route va au village = est telle qu’elle permet d’aller au village . L’autre volet consiste à montrer que les compléments en avec , où la préposition donne le rôle d’instrument au nom, ne sont pas, en tant que groupes, des arguments du verbe, mais des réalisations du constituant « manière » : non pas de la manière de l’action elle-même, comme les adverbes de manière, qui modifient le verbe, mais de la manière de faire pour que l’action soit accomplie – ils seraient donc plutôt des modifieurs de “v” ( comment as-tu fait pour ouvrir cette porte ? Je l’ai ouverte avec ma clé ). On arrive donc à la conclusion que le verbe agentif d’une phrase ne donne jamais lui-même le rôle d’instrument à un groupe nominal de son contexte.
L'expression de la causation en français et en arabe : une comparaison à la lumière de la linguistique cognitive
Authors: Ben Gharbia Abdeljabbar
Published: March 2011

Résumé Après une brève présentation de quelques notions cognitives telles que la disposition sémantique en couches et l’intégration de l’événement , nous nous sommes livré à l’examen des modes d’expression de la causation en français et en arabe, et avons vérifié l’hypothèse selon laquelle il y aurait une corrélation systématique entre le niveau d’élaboration sémantique du processus subordonné et le degré de son intégration syntaxique dans le processus principal. Cette étude nous a permis de constater que l’ordre VVO avec ‘ faire ’ en français est réservé à l’expression de la causation factitive forte, et l’ordre VOV avec ‘ laisser ’ et ‘ obliger à… ’ à l’expression de la causation faible. L’arabe, quant à lui, permet, en plus de la causation faible, d’exprimer deux types de causation factitive : une forte avec les formes verbales II et IV, et une faible avec le verbe schématique ?a’ala ‘FAIRE’, qui exige que son site ( i.e. complément) soit agentif. Le caractère polysémique de ces deux procédés a, par la suite, retenu notre attention. Nous avons mis en lumière les correspondances systématiques entre les significations de ces procédés et la structure syntaxique du site qu’ils requièrent.