bluuebunny/crossref_metadata_2025 huggingface dataset:
Seismic Performance of Two-Side Structural Silicone Glazing Systems
Authors: Memari AM , Chen X , Kremer PA , Behr RA
Published: September 2006

This paper presents the results of the first phase of an experimental research program on simulated seismic performance of structural silicone glazed (SSG) curtain wall systems. Full-scale, two-side SSG mockups made up of three side-by-side glass panels were tested under cyclic racking displacements to determine serviceability and ultimate behavior responses. Variables were glass type (annealed and fully tempered) and panel configuration (monolithic, laminated, and insulating glass). In the experiments carried out, damage states such as gasket deformation/pullout, sealant failure (e.g., adhesion/cohesion, etc.), glass cracking glass and fallout were identified and their corresponding drift levels were determined. The extent of damage to silicone sealant was determined through air leakage tests.
Expression of endothelial nitric oxide synthase in the ovine ovary throughout the estrous cycle
Authors: Grazul-Bilska Anna T , Navanukraw Chainarong , Johnson Mary Lynn , Arnold Daniel A , Reynolds Lawrence P , Redmer Dale A
Published: September 2006

This study was conducted to evaluate the expression of endothelial nitric oxide synthase (eNOS) in ovarian follicles and corpora lutea (CL) throughout the estrous cycle in sheep. Three experiments were conducted to (1) immunolocalize eNOS protein, (2) determine expression of mRNA for eNOS and its receptor guanylate cyclase 1 soluble β3 (GUCY1B3), and (3) co-localize eNOS and vascular endothelial growth factor (VEGF) proteins in the follicles and/or CL throughout the estrous cycle. In experiment 1, ovaries were collected from ewes treated with FSH, to induce follicular growth or atresia. In experiment 2, ovaries were collected from ewes treated with FSH and hCG to induce follicular growth and ovulation. In experiment 3, ovaries were collected from superovulated ewes to generate multiple CL on days 2, 4, 10, and 15 of the estrous cycle. In experiments 1 and 2, the expression of eNOS protein was detected in the blood vessels of the theca externa and interna of healthy ovarian follicles. However, in early and advanced atretic follicles, eNOS protein expression was absent or reduced. During the immediate postovulatory period, eNOS protein expression was detected in thecal-derived cells that appeared to be invading the granulosa layer. Expression of eNOS mRNA tended to increase in granulosa cells at 12 and 24 h, and in theca cells 48 h after hCG injection. In experiment 3, eNOS protein was located in the blood vessels of the CL during the estrous cycle. Dual localization of eNOS and VEGF proteins in the CL demonstrated that both were found in the blood vessels.
Phodopus campbelli detect reduced photoperiod during development but, unlike Phodopus sungorus, retain functional reproductive physiology
Authors: Timonin Mary E , Place Ned J , Wanderi Esther , Wynne-Edwards Katherine E
Published: September 2006

Golden (Mesocricetus auratus) and Siberian (Phodopus sungorus) hamsters are widely used as animal models for seasonal reproduction; but M. auratus shows no developmental delay in short days until after sexual maturity, whereas P. sungorus juveniles delay development in short days. As the photoperiodic response of Phodopus campbelli is not well established, litters of the two Phodopus species were gestated and reared under long days (14 h light:10 h darkness) or short days (10 h light:14 h darkness) until 70 days of age. As expected, under short photoperiod P. sungorus showed reduced body, testes, epididymides, uterus, and ovary weight; antral follicles and corpora lutea were absent and vaginae remained closed. Animals moulted to winter pelage, and low concentrations of each of leptin, testosterone, and prolactin were present in male serum. Phodopus campbelli juveniles also responded to the short photoperiod as measured by reduced body, testes, epididymides, and ovary weight. The summer pelage persisted. However, both sexes of P. campbelli developed functional reproduction under 10 h light:14 h darkness. All females had a patent vagina by 10 weeks; ovaries contained antral follicles and corpora lutea, and uteri were not reduced in weight. In males, the concentrations of testosterone, leptin, and prolactin were not reduced by short photoperiod. Developmental patterns in the three species of hamster, therefore, differ and are not predicted by relatedness or latitude of origin. Other ecological traits, such as predictability of summer rainfall, ambient temperature, and differential responses to social cues might be important.
Administration of vascular endothelial growth factor Trap during the ‘post-angiogenic’ period of the luteal phase causes rapid functional luteolysis and selective endothelial cell death in the marmoset
Authors: Fraser Hamish M , Wilson Helen , Wulff Christine , Rudge John S , Wiegand Stanley J
Published: September 2006

The intense angiogenesis characteristic of early corpus luteum development is dependent upon vascular endothelial growth factor (VEGF) as inhibitors of VEGF administered at the peri-ovulatory period suppress endothelial cell proliferation and progesterone secretion. We now report that administration of VEGF Trap, a soluble decoy receptor-based inhibitor, at the mid- or the late luteal phase in the marmoset results in a rapid decline in plasma progesterone. Since vascularisation of the corpus luteum is largely complete by the mid-luteal phase, it suggested that this functional luteolysis involved mechanisms other than inhibition of angiogenesis. A second experiment investigated the role of VEGF in maintaining the integrity of the luteal vasculature and hormone-producing cells. VEGF Trap was administered to marmosets in the mid-luteal phase and ovaries were obtained 1, 2, 4 or 8 days later for localisation of activated caspase-3 staining in the corpus luteum and compared with those obtained 2, 4 and 8 days after administration of control protein. The number of cells with activated caspase-3 staining was significantly increased after administration of VEGF Trap. Dual staining of activated caspase-3 with the endothelial cell marker CD31 showed that at 1 day post-treatment, more than 90% caspase-3-stained cells were vascular endothelium, prior to detection of an increasing incidence in death of hormone-producing cells on days 2 and 4. Staining with CD31 showed that the endothelial cell area was decreased after treatment. By 8 days after treatment, corpora lutea had regressed to varying degrees, while all control corpora lutea remained healthy. These results show that VEGF inhibition in the mid- or the late luteal phase induces functional luteolysis in the marmoset that is associated with premature and selective death of endothelial cells.
Abilities of cumulus and granulosa cells to enhance the developmental competence of bovine oocytes during in vitro maturation period are promoted by midkine; a possible implication of its apoptosis suppressing effects
Authors: Ikeda S , Saeki K , Imai H , Yamada M
Published: September 2006

We previously reported that when midkine (MK), a heparin-binding growth differentiation factor was used in in vitro maturation (IVM) culture of bovine cumulus-enclosed oocytes (CEOs), their developmental competence to the blastocyst stage after in vitro fertilization (IVF) was enhanced and the effect of MK might be mediated by its action upon mural granulosa cells and cumulus cells that closely surround the oocyte. In the present study, when denuded oocytes (DOs) were matured in IVM medium with or without MK (200 ng/ml) in the presence or absence of isolated cumulus cell masses and subjected to IVF, the enhancing effects of MK on the developmental competence of DOs to the blastocyst stage after IVF were exerted only in the presence of cumulus cells. In addition, we prepared the conditioned media of granulosa cells cultured with or without 200 ng MK/ml (CMMK+ or CMMK− respectively) and examined their effects on the IVM of DOs in terms of their developmental competence to the blastocyst stage after IVF. The supplementation of CMMK+ into IVM medium at 40% (v/v) significantly enhanced the blastocyst development compared with the no additive control and the CMMK− supplemented groups. Furthermore, the effects of MK during IVM of bovine CEOs on the cumulus cell apoptosis were investigated. CEOs were cultured up to 24 h in IVM medium without (control) or with 200 ng MK/ml. The genomic DNA was extracted from CEOs at 0, 6, 12, 18 and 24 h of IVM and subjected to ligation-mediated PCR (LM-PCR) to detect the apoptotic internucleosomal DNA fragmentation. DNA fragmentation was scarcely detected at the start of IVM, whereas it increased time-dependently as the IVM culture progressed. The degree of the fragmentation was significantly lower in the MK-treatment group compared with the control group at 18 and 24 h of IVM. The apoptosis-suppressing effect of MK on cumulus cells was further confirmed in situ by using TUNEL on CEOs. In conclusion, data from the present study further confirmed that MK enhances the developmental competence of bovine oocytes via cumulus and granulosa cells. It was also demonstrated that MK suppresses the apoptosis that occurs in cumulus cells during the period of IVM of bovine CEOs. The putative soluble factor(s) from cumulus cells was suggested from the experiment using CMMK+ . MK may promote the production of such factors in part by its anti-apoptotic effects on cumulus cells.
Successful transplantation of bovine testicular cells to heterologous recipients
Authors: Herrid Muren , Vignarajan Soma , Davey Rhonda , Dobrinski Ina , Hill Jonathan R
Published: September 2006

While heterologous germ cell transplantation was successful in pigs and goats, autologous transplantation alone has been reported to result in donor-derived spermatogenesis in cattle. The objective of this study was to investigate whether the transplantation of heterologous germ cells could result in colonization of recipient testes in cattle of different breeds. Testicular cells were isolated from 8 Bos taurus donor bull calves and then transferred into 15 Bos indicus-cross bull calves. All animals were prepubertal, donors were aged 5–7 months and recipients 5–11 months, and scrotal circumferences ranged from 15 to 22 cm. Single cell suspensions of donor testicular cells, prepared by enzymatic digestion, were labelled with fluorescent dyes PKH26 or CFDA-SE, before transfer into the rete testis of recipients under ultrasonographic guidance. To assess the longevity of colonization by donor cells, recipients were castrated 2–30 weeks after cell transfer. Donor cells were observed in 15/25 (60%) of the testes that received PKH26-labelled cells, whereas no CFDA-SE-positive cell was identified in any recipients. The maturity of the donors or recipients (measured by scrotal circumference) did not affect colonization potential. In freshly isolated tubules, clumps of PKH26-positive cells were observed, which indicated either cell division or extensive local colonization of specific areas of the tubules. In frozen sections, PKH26-positive cells were identified on the seminiferous tubule basement membrane, which indicated that these cells had successfully migrated from the tubule lumen and were likely to be spermatogonia. We conclude that PKH26 was more suitable for labelling donor testis cells and donor cells can be identified up to 6 months following transfer. These results indicate that allogeneic transplantation of testicular cells can occur between Bos taurus and Bos indicus cattle. Further studies will investigate functionality of transferred testicular cells.
A bovine oviduct epithelial cell suspension culture system suitable for studying embryo–maternal interactions: morphological and functional characterization
Authors: Rottmayer Regine , Ulbrich Susanne E , Kölle Sabine , Prelle Katja , Neumueller Christine , Sinowatz Fred , Meyer Heinrich H D , Wolf Eckhard , Hiendleder Stefan
Published: September 2006

We established a short-term (24 h) culture system for bovine oviduct epithelial cells (BOECs), obtained on day 3.5 of the estrous cycle and evaluated the cells with respect to morphological criteria, marker gene expression, and hormone responsiveness. BOEC sheets were isolated mechanically from the ampulla with similar yields from oviducts ipsi- and contralateral to the ovulation site (57.9 ± 4.6 and 56.4 ± 8.0 × 106 cells). BOECs showed > 95% purity and cells cultured for 24 h maintained morphological characteristics present in vivo, as determined by light microscopy, scanning electron microscopy, and transmission electron microscopy. Both secretory cells with numerous secretory granules and ciliated cells with long, well-developed, and vigorously beating kinocilia were visible. Quantitative real-time PCR failed to detect significant differences in transcript levels between ipsi-and contralateral BOECs for the majority of marker genes (estrogen receptors α and β (ESR1 and ESR2), 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR), oviductal glycoprotein 1 (OVGP1), progesterone receptor (PGR), and tumor rejection antigen 1 (TRA1)) throughout the 24 h culture period. However, the combined data of all time points for glutathione peroxidase 4 (GPX4), a gene previously shown to be expressed at higher levels in the ipsilateral oviduct in vivo, also indicated significantly different mRNA levels in vitro. The expression of marker genes remained stable after 6 h cell culture, indicating only a short adaptation period. Western blot analysis confirmed ESR1 and PGR protein expression throughout the culture period. In agreement with cyclic differences in vivo, estradiol-17β stimulation increased PGR transcript abundance in BOECs. Our novel culture system provides functional BOECs in sufficient quantities for holistic transcriptome and proteome studies, e.g. for deciphering early embryo–maternal communication.
Bioacoustics of Fishes of the Family Sciaenidae (Croakers and Drums)
Authors: Ramcharitar John , Gannon Damon P. , Popper Arthur N.
Published: September 2006

The teleost family Sciaenidae, collectively known as the croakers and drums because of their propensity for making sound, includes roughly 70 genera and 270 species worldwide. Although many other groups of fish also communicate using sound, the sciaenids are unique in the diversity of their sound production mechanisms, variety of sounds produced, and structural variation in sound‐detecting structures. This paper reviews the bioacoustics of sciaenid fishes, including mechanisms involved in the production and reception of sound, the types of sounds produced, and the functions of these sounds. We propose the hypothesis that the unusual diversity in the design of the structures associated with sound production and detection is correlated with a similar diversity in how these structures function. Production and detection of sound appear to be important aspects of sciaenid behavior. But despite the vast literature on sciaenid sound production, we know relatively little about the biological significance of their sounds. This lack of understanding leaves plenty of room for research by physiologists, bioacousticians, behavioral ecologists, and fisheries scientists.
Predicting Postrelease Survival in Large Pelagic Fish
Authors: Moyes Christopher D. , Fragoso Nuno , Musyl Michael K. , Brill Richard W.
Published: September 2006

Sharks, turtles, billfish, and marine mammals are frequently caught accidentally in commercial fisheries. Although conservationists and fisheries managers encourage the release of these nontarget species, the long‐term outcome of released animals is uncertain. Using blue sharks Prionace glauca, we developed a model to predict the long‐term survival of released animals based on analysis of small blood samples. About 5% of the sharks were landed in obviously poor condition (lethargic and unresponsive to handling); these moribund sharks were sampled and euthanized. A subset of the remaining sharks was sampled and tagged with pop‐up satellite archival tags (PSATs). Each of the PSATs that reported data (11 tags) showed that the sharks roamed at sea for at least 3 weeks postrelease. Five variables differentiated moribund sharks from survivors: Plasma Mg2+ (moribund, 1.57 ± 0.08 mM; survivor, 0.98 ± 0.05 mM; P < 0.00001), plasma lactate (moribund, 27.7 ± 4.1 mM; survivor, 5.80 ± 2.96 mM; P < 0.001), erythrocyte heat shock protein 70 (Hsp70) mRNA (relative levels: Moribund, 3.96 ± 0.53; survivor, 1.00 ± 0.29; P < 0.005), plasma Ca2+ (moribund, 3.70 ± 0.14 mM; survivor, 3.13 ± 0.11; P < 0.005), and plasma K+ (moribund, 7.01 ± 0.66 mM; survivor, 5.12 ± 0.44 mM; P < 0.05). These analyses were used to develop logistic regression models that could “predict” the long‐term survival of captured sharks, including a larger group of sharks that we sampled but did not tag. The best logistic model, which incorporated Mg2+ and lactate, successfully categorized 95% of fish of known outcome (19 of 20). These analyses suggest that sharks landed in an apparently healthy condition are likely to survive long term if released (95% survival based on biochemical analyses; 100% based on PSATs).
Exploring Notions of Freedom In and Through Young Adult Literature
Authors: Bean Thomas W. , Harper Helen J.
Published: September 2006

This article offers teachers a critical framework for use and adaptation in organizing class discussions focused on notions of freedom in young adult literature. The authors open by discussing the notion of freedom, including concepts related to negative and positive freedom and to arguments advocating critical discussion of common assumptions surrounding individual freedom and collective responsibility. Examples of classroom questions drawn from a critical literacy framework center on two award‐winning young adult novels, The Breadwinner by Deborah Ellis and The Other Side of Truth by Beverly Naidoo.

Classrooms offer a community where notions of freedom depicted in young adult novels located in war zones can be considered through a critical literacy lens. In addition to the novels discussed in the article, the authors provide a list of other young adult literature for teachers to consider for use in their classrooms.
Three Foci of an Effective High School Generation 1.5 Literacy Program
Authors: Forrest Scott N.
Published: September 2006

There is an increasing amount of research and discussion about the characteristics and learning needs of “Generation 1.5.” These learners share characteristics of both first‐ and second‐generation immigrants; they have grown up and been educated in the United States, but live in homes where English is not the primary language. They often have considereable fluency in social English but less fluency in academic language.

To date, most research focused on the Generation 1.5 population has considered college and adult levels. However, the needs of Generation 1.5 high school students must be considered in light of how curriculum, learning strategies, and teaching strategies affect their literacy development. This article presents recommendations as a framework through which to develop a high school literacy program that meets the needs of the Generation 1.5 population. The nine recommendations are categorized within three areas of focus: curriculum centered, learner centered, and educator centered.
Access and Benefits: Assistive Technology in Adult Literacy
Authors: Silver‐Pacuilla Heidi
Published: September 2006

Through access to assistive technology, adult students with learning disabilities can improve their literacy skills and goal attainment as a supplement to regular adult basic education classes.

This article describes a project that investigated whether increased engagement with text‐to‐speech and speech‐recognition software could improve participants' foundational literacy skills. Data were gathered through careful observations as well as reflective dialogue with the learners. Three layers are explored:

The underlying framework of dialogic research

Thematic analysis of students' interactions with the equipment

Thematic analysis of the role of the coach

Through a series of snapshots of students' approaches to literacy learning with assistive technology and a cross‐case analysis, possibilities and complexities are revealed in the intersection of literacy and technology.
Persistent Tobacco Use During Pregnancy and the Likelihood of Psychiatric Disorders
Authors: Flick Louise H. , Cook Cynthia A. , Homan Sharon M. , McSweeney Maryellen , Campbell Claudia , Parnell Lisa
Published: September 2006

Objectives. We examined the association between psychiatric disorders and tobacco use during pregnancy.

Methods. Data were derived from a population-based cohort of 744 pregnant African American and White low-income women living in urban and rural areas. The Diagnostic Interview Schedule was used to assess women for 20 different psychiatric disorders.

Results. In comparison with nonusers, persistent tobacco users (women who had used tobacco after confirmation of their pregnancy) and nonpersistent users (women who had used tobacco but not after pregnancy confirmation) were 2.5 and 2 times as likely to have a psychiatric disorder. Twenty-five percent of persistent users had at least 1 of the following diagnoses: generalized anxiety disorder, bipolar I disorder, oppositional disorder, drug abuse or dependence, and attention deficit–hyperactivity disorder.

Conclusions. In this cohort study, 5 diagnoses were more prevalent among persistent tobacco users than among nonusers, suggesting that several psychiatric disorders contribute to difficulty discontinuing tobacco use during pregnancy. Smoking cessation efforts focusing on pregnant women may need to address co-occurring psychiatric disorders if they are to be successful.
Consumption of Soft Drinks and Hyperactivity, Mental Distress, and Conduct Problems Among Adolescents in Oslo, Norway
Authors: Lien Lars , Lien Nanna , Heyerdahl Sonja , Thoresen Magne , Bjertness Espen
Published: September 2006

Objectives. We examined whether high levels of consumption of sugar-containing soft drinks were associated with mental distress, hyperactivity, and conduct problems among adolescents.

Methods. A cross-sectional population-based survey was conducted with 10th-grade students in Oslo, Norway (n = 5498). We used the Hopkins Symptom Checklist and the Strengths and Difficulties Questionnaire to assess mental health outcomes.

Results. There was a J-shaped dose–response relationship between soft drink consumption and mental distress, conduct problems, and total mental health difficulties score; that is, adolescents who did not consume soft drinks had higher scores (indicating worse symptoms) than those who consumed soft drinks at moderate levels but lower scores than those with high consumption levels. The relationship was linear for hyperactivity. In a logistic regression model, the association between soft drink consumption and mental health problems remained significant after adjustment for behavioral, social, and food-related variables. The highest adjusted odds ratios were observed for conduct problems among boys and girls who consumed 4 or more glasses of sugar-containing soft drinks per day.

Conclusions. High consumption levels of sugar-containing soft drinks were associated with mental health problems among adolescents even after adjustment for possible confounders.
Employee and Customer Injury During Violent Crimes in Retail and Service Businesses
Authors: Peek-Asa Corinne , Casteel Carri , Kraus Jess F. , Whitten Paul
Published: September 2006

Objectives. We sought to compare the frequency and risk factors for employees and customers injured during crimes in retail (convenience, grocery, and liquor stores) and service businesses (bars, restaurants, motels).

Methods. A total of 827 retail and service businesses in Los Angeles were randomly selected. Police crime reports (n=2029) from violent crimes that occurred in these businesses from January 1996 through June 2001 were individually reviewed to determine whether a customer or an employee was injured and to collect study variables.

Results. A customer injury was 31% more likely (95% confidence interval [CI]=1.11, 1.51) than an employee injury during a violent crime. Customer injury was more frequent than employee injury during violent crimes in bars, restaurants, convenience stores, and motels but less likely in grocery or liquor stores. Injury risk was increased for both employees and customers when resisting the perpetrator and when the perpetrator was suspected of using alcohol. Customers had an increased risk for injury during crimes that occurred outside (relative risk [RR]=2.01; 95% CI=1.57, 2.58) and at night (RR=1.79; 95% CI=1.40, 2.29).

Conclusions. Security programs should be designed to protect customers as well as employees.
Trends in Mental Health and Substance Abuse Services at the Nation’s Community Health Centers: 1998–2003
Authors: Druss Benjamin G. , Bornemann Thomas , Fry-Johnson Yvonne W. , McCombs Harriet G. , Politzer Robert M. , Rust George
Published: September 2006

Objective. We examined trends in delivery of mental health and substance abuse services at the nation’s community health centers.

Methods. Analyses used data from the Health Resources and Services Administration (HRSA), Bureau of Primary Care’s (BPHC) 1998 and 2003 Uniform Data System, merged with county-level data.

Results. Between 1998 and 2003, the number of patients diagnosed with a mental health/substance abuse disorder in community health centers increased from 210 000 to 800 000. There was an increase in the number of patients per specialty mental health/substance abuse treatment provider and a decline in the mean number of patient visits, from 7.3 visits per patient to 3.5 by 2003. Although most community health centers had some on-site mental health/substance abuse services, centers without on-site services were more likely to be located in counties with fewer mental health/substance abuse clinicians, psychiatric emergency rooms, and inpatient hospitals.

Conclusions. Community health centers are playing an increasingly central role in providing mental health/substance abuse treatment services in the United States. It is critical both to ensure that these centers have adequate resources for providing mental health/substance abuse care and that they develop effective linkages with mental health/substance abuse clinicians in the communities they serve.
Childhood Trauma and Women’s Health Outcomes in a California Prison Population
Authors: Messina Nena , Grella Christine
Published: September 2006

Objectives. We sought to describe the prevalence of childhood traumatic events among incarcerated women in substance abuse treatment and to assess the relation between cumulative childhood traumatic events and adult physical and mental health problems.

Methods. The study was modeled after the Adverse Childhood Events study’s findings. In-depth baseline interview data for 500 women participating in the Female Offender Treatment and Employment Program evaluation were analyzed.

Results. Hypotheses were supported, and regression results showed that the impact of childhood traumatic events on health outcomes is strong and cumulative (greater exposure to childhood traumatic events increased the likelihood of 12 of 18 health-related outcomes, ranging from a 15% increase in the odds of reporting fair/poor health to a 40% increase in the odds of mental health treatment in adulthood).

Conclusions. Our findings suggest a need for early prevention and intervention, and appropriate trauma treatment, within correctional treatment settings.
Breast Cancer in Young Women: Climbing for Progress in Care and Knowledge
Authors: Pagani Olivia , Goldhirsch Aron
Published: September 2006

Approximately a third of newly diagnosed invasive breast cancers occur in women aged under 50 years and it is likely that the incidence of the disease in younger women will further increase as a result of demographic and lifestyle changes and progress in screening. Breast cancer in young women is different from that in older patients. Young women with breast cancer represent a distinct population for which tailored diagnostic, therapeutic and supportive interventions are required. This review highlights the complex diagnostic and therapeutic processes that women and care providers are faced with. Topics addressed include the need for more sensitive and specific diagnostic tools that are capable of detecting cancer in dense breasts, the development of individualized surgical and medical treatments in the early and advanced disease setting aimed at improving outcome and reducing long-term side effects, and adequate psychosocial interventions.
Current and Future Developments in Screening for Ovarian Cancer
Authors: Urban Nicole , Drescher Charles
Published: September 2006

Over 90% of women diagnosed with localized ovarian cancer survive at least 5 years, but because the disease is often advanced at diagnosis, only half of patients survive that long. Currently, screening is only recommended for women with a strong family history of the disease, for whom prophylactic surgery is appropriate once childbearing is complete. Screening is not recommended for the general population since currently available screening tests seldom detect curable tumors, and often lead to unnecessary surgery. New markers are under investigation that may signal disease earlier and be useful in a marker panel to select women for imaging and/or surgery. A clinical challenge is that definitive diagnosis requires major abdominal surgery, and screening tests often detect benign ovarian conditions. A challenge for translational research in biomarkers for early detection is that access is needed to preclinical blood samples, obtained some months prior to diagnosis, in order to determine if candidate markers can detect disease prior to onset of symptoms.
Water Treatment
Authors: Singley J. E. , Robinson James ,   Updated by Staff
Published: September 2006

Most surface waters contain varying amounts of suspended solids, including silt, clay, bacteria, viruses, etc. It is necessary to remove these prior to distribution to domestic or industrial customers. Abundant supplies of fresh water are essential to the development of industry. Enormous quantities are required for the cooling of products and equipment, for process needs, for boiler feed, and for sanitary and potable water supply. Sedimentation and filtration are the principal treatment processes for both municipal and industrial water. These are discussed in detail. Also discussed is the removal of colloidal particles by coagulation and flocculation. Lime and lime‐soda processes, and ion exchange are used to control hardness of water. Data on taste and odor control methods, as well as removal of organic compounds, nitrates, arsenic, and radionuclides iron and manganese, which impact on potable water quality, are given. This article also gives details on the various impurities found in water and how the water is treated to make it acceptable for industrial use. Clarification, precipitation, settling, filtration, ion exchange, and membrane processes are all detailed. Particular attention is given to corrosion control in boilers. Condensate systems can be chemically treated to reduce metal corrosion, especially important in cooling systems. Types of corrosion, eg, pitting, galvanic corrosion, are discussed. Deposit accumulations in cooling systems, biofouling and microfouling organisms are also summarized.
Reactor Technology
Authors: Mann Uzi
Published: September 2006

This article provides an overview of the phenomena and mechanisms that are encountered in the operations of chemical reactors and of the concepts and methods used to describe them. The primary theme of the commentary is the wide spectrum of chemical reactor applications and operating conditions, and the multitude of diverse factors that affect reactor operations. Chemical reactions are classified according to common characteristics (single phase, multiple‐phase, solid‐phase catalytic, etc). Chemical reactors are classified according to their operating mode, configuration, and the way multi‐phase reactants are contacted. Fundamental principles, both physical and chemical, are reviewed and the underlying limitations in applying them are identified and discussed. The design equations of idealized reactor configurations are presented and methods for solving them simultaneously with the energy balance equations are discussed. Common engineering practices that are applied over the entire scope of chemical reactor development are reviewed, including experimental reactors, selection of reactor configuration and operating conditions, and diagnostics. Selected examples of industrial reactors are described.
Silicon Carbide
Authors: Wright Nicholas G.
Published: September 2006

Silicon carbide (SiC) is a crystalline material having a color that varies from nearly clear through pale yellow or green to black, depending on the amount of impurities. It occurs naturally only as the mineral moissanite in the meteorite iron of Canon Diablo, Arizona. The commercial product, which is made in an electric furnace, is usually obtained as an aggregate of iridescent crystals. The iridescence is caused by a thin layer of silica produced by superficial oxidation of the carbide. The loose black or green grain of commerce is prepared from the manufactured product by crushing and grading for size. Traditionally, the metallurgical, abrasive, and refractory industries are the largest users of silicon carbide. SiC is also used for heating elements in electric furnaces, electronic devices, and applications where its resistance to nuclear radiation damage is advantageous. The development of advanced pressureless sintering and complex shape‐forming technologies has led to silicon carbide becoming one of the most important structural ceramics. Silicon carbide has found wide acceptance in wear‐, erosion‐, and corrosion‐resistant applications; it has demonstrated excellent performance as a heat‐exchanger material; it is also being evaluated for prototype high temperature gas turbine engine component applications. The measurements made on commercial, polycrystalline products should not be interpreted as being representative of single‐crystal silicon carbide. The pressureless‐sintered silicon carbides, being essentially single‐phase, fine‐grained, and polycrystalline, have properties distinct from both single crystals and direct‐bonded silicon carbide refractories. Silicon carbide may crystallize in the cubic, hexagonal, or rhombohedral structure. Silicon carbide is a leading candidate material for rotating and static components in many gas turbine engine applications. As is the case for other ceramics, silicon carbide is brittle in nature. The strength of a silicon carbide component is determined by preexisting flaws introduced into the material during processing. Sintered silicon carbide retains its strength at elevated temperatures. Silicon carbide is a semiconductor: It has a conductivity between that of metals and insulators or dielectrics. Silicon carbide is comparatively stable. The only violent reaction occurs when SiC is heated with a mixture of potassium dichromate and lead chromate. There are several routes to preparing SiC powders. Methods that have been examined include growth by sublimation from the vapor phase, carbothermic reduction, and crystallization from a melt. The high modulus, high intrinsic strength, and temperature stability make SiC, in the form of whiskers, platelets, and fibers, a promising candidate reinforcement material for metal, polymer, and ceramic matrix composites. Silicon carbide has been described as a mild inhalation irritant. The threshold limit value for silicon carbide in the atmosphere is 5 mg/m3.
Steam
Authors: Bellows James
Published: September 2006

Steam is the most important industrially used vapor and, after water, the most common and important fluid used in chemical technology. It can be generated by evaporation of water at subcritical pressures, by heating water above the critical pressure, and by sublimation of ice. Steam is used in electric power generation; for driving mechanical devices; for distribution of heat; as a reaction medium; as a solvent; as a cleaning, blanketing, or smothering agent; and as a distillation aid. Steam not only has high latent heat, moderate density, and nonpolluting properties, but also provides easy control of temperature in processes and heating application. Steam is generated from water by boiling, flash evaporation, and throttling from high to low pressure. The phase change occurs along the saturation line with the specific volume of steam larger than that of the boiling water. Thermal energy (heat of evaporation) is absorbed during the process. At the critical and supercritical pressures, the water–steam distinction disappears. The thermodynamic and physical properties of pure steam are well established over the range of pressures and temperatures used. Corrosion of containment materials and purity of water are important to steam production.
Styrene
Authors: Chen Shiou‐Shan ,   Updated by Staff
Published: September 2006

Chen, Shiou‐Shan (Raytheon Engineers & Constructors). Styrene, the simplest and most important member of a series of aromatic monomers, is produced in large quantities for polymerization. Its versatility has resulted in the manufacture of plastics, including polystyrene, ABS, SAN, styrene–butadiene latex, SBR, and unsaturated polyester resins. Polystyrene accounts for 65% of total styrene demand. Rapid growth in styrene production has been seen worldwide since 1970, including, since the 1980s, in the Pacific Rim. The fastest growing demand in 2006 is in South America, Eastern Europe, and the Middle East. Many factors contribute to its growth. Chief among these are that it can be polymerized and copolymerized under a variety of conditions by common methods and that the raw materials, benzene and ethylene, are produced in large quantities in refineries and can be supplied through pipelines. The two process routes used commercially for manufacture of styrene, dehydrogenation, and coproduction with propylene oxide, are covered. Both routes use ethylbenzene as the intermediate.

The commodity nature of the product and easy access to licensed processes have enabled new producers in developing countries to enter the global styrene market. Timing is important as price fluctuates broadly and rapidly. A large number of styrene derivatives have been reported, and several have been used for manufacturing small‐volume specialty polymers, including vinyltoluene,
para
‐methylstyrene, α‐methylstyrene, and divinylbenzene.
Styrene Plastics
Authors: Priddy Duane B. ,   Updated by Staff
Published: September 2006

This article examines both styrene plastics, including such commodity styrenic resins as general‐purpose polystyrene, high impact polystyrene, styrene–acrylonitrile, and acrylonitrile–butadiene–styrene, and specialty resins such as ionomers, styrene derivatives, and tactic polystyrenes. Topics discussed include styrenic plastic properties such as stress–strain, creep, stress relaxation, fatigue, impact strength, surface appearance, and melt properties, as well as rubber modification and glass filling of styrene plastics. Styrene plastics manufacturing processes and the chemistry of styrene polymerization are both described, the former with an emphasis on the most widely used continuous free‐radical reaction designs, the latter mainly on the industrially important free‐radical mechanism; other mechanisms by which styrene can be polymerized, ie, anionic, cationic, and Ziegler‐Natta, are also mentioned. The description of free‐radical polymerization of styrene covers spontaneous initiation, chemical initiators, chain‐transfer agents, and living free‐radical polymerization. Copolymerization of styrene with other monomers is also discussed. Other topics covered include fabrication processes, ie, injection molding, extrusion, thermoforming, and blow molding; additives; economic aspects; characterization techniques; health and safety issues; foamed polystyrene; and environmental issues, including recycling.
Thorium and Thorium Compounds
Authors: Clark David L. , Neu Mary P. , Runde Wolfgang , Keogh D. Webster
Published: September 2006

An overview is provided on thorium and thorium compounds with an emphasis on their relevance to chemical technology. The main interest in thorium is as a nuclear fuel, but thorium and its compounds have many specialty uses including lantern mantles and catalysts. Discussion on the occurrence, recovery, preparation, properties and radiochemistry of thorium is provided. While not intending to be exhaustive, a broad based review is provided on the coordination and organometallic complexes of thorium with halogens; N, P, and O donors; cyclopentadienyl; annulene; hydrocarbyl; and allyl ligands. A drawback to using thorium in many processes is the chemical reactivity of the metal as well as the inherent radioactivity of all thorium isotopes. As such, health and safety factors essential for working with thorium are discussed. General references from which more detailed information of the aforementioned subjects is provided.
Transportation
Authors: Moreno Jeffrey O. , Prange Laurence W.
Published: September 2006

A wide range of issues and matters relevant to the transport of chemicals is addressed. In particular, the various modes of transport, including railroad, motor carrier, water carrier, pipelines, and air transport, and the role played by each in the transport of chemicals is discussed. In addition, the significance of regularly used shipping terms and documents are explained. The different laws applicable to interstate and intrastate transportation, and how to identify under which jurisdiction a particular shipment will be regulated, also are addressed. Changes in the economic regulation of the various modes of transport are explained and the significance of those changes to chemicals shippers is explored. Economic regulation includes important distinctions between contract, common, and private carriage, and the allocation of responsibility between shippers and carriers for freight loss and damage. Finally, safety and hazardous materials transport regulations, a critical concern for chemical shippers and carriers alike, are discussed.
Microfluidics
Authors: Lii Jerry , Hsu Wern‐Jir , Lee Stephanie P. , Sia Samuel K.
Published: September 2006

Microfluidics is a technology that features the movement of small volumes of fluids through microscale channels. It provides a powerful and precise research platform for studying basic phenomena of fluid flow at the microscale, and a powerful analytical platform for conducting experimental assays. This article discusses the basic features and applications of microfluidics.
Dimensional stability of wood–polymer composites
Authors: Zhang Yaolin , Zhang S. Y. , Yang Dian Qing , Wan Hui
Published: September 2006

Wood–polymer composites (WPC) were prepared by impregnation of polymeric monomers in wood and in situ polymerization. Three polymeric chemicals were chosen for this study: methyl methacrylate (MMA), hydroxyethylene methacrylate (HEMA), and ethylene glycol dimethacrylate (EGDMA). The effects of polymeric monomers and their combinations on moisture adsorption (M), anti–moisture adsorption efficiency (AME), liquid water uptake (D), water repellency efficiency (WRE), longitudinal, radial, tangential, and volumetric swelling properties (S) after soaking, and antiswelling efficiency (ASE) were investigated. It was found that M was different for different methacrylate combinations and depended not only on the composition of the impregnants, but also on wood properties. Liquid water uptake was similar regardless of the formulation of the WPC. Wood–polymer composites with high MMA content displayed enhanced dimensional stabilities, but WPCs with high HEMA content did not. Tangential and volumetric ASEs were strongly dependent on the type of treatment. Mold growth tests showed that wood treated with HEMA alone had no surface mold growth, and wood treated with MMA alone also showed less mold growth than did the control samples. © 2006 Wiley Periodicals, Inc. J Appl PolymSci 102: 5085–5094, 2006
Polyaniline/poly(ethylene terephthalate) conducting composite fabric with improved fastness to washing
Authors: Huang Huihua , Liu Weijin
Published: September 2006

In this article, we report a novel method for the design and development of a polyaniline (PANI)/poly(ethylene terephthalate) (PET) conducting composite fabric based on in situ polymerization. With the aim of improving fabric–PANI adhesion and good fastness to washing, we took some special steps: the alkali reduction pretreatment of the PET fabric before the polymerization of aniline onto the fabric, the introduction of squeezing the laboratory padder on the fabric to push the reagent into the inner part of the fabric, and short immersion time of the aniline‐absorbed fabric in oxidant solution. Factors affecting the conductivity and fastness to washing, including the alkali reduction percentage, the wet pickup of the reagent‐absorbed fabric, the immersion time in oxidant solution, and the reaction time, are discussed. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5775–5780, 2006
Crystallization behavior of nylon 11/montmorillonite nanocomposites under annealing
Authors: Zhang Xikui , Yang Guisheng , Lin Jiaping
Published: September 2006

Exfoliated nylon 11/montmorillonite (MMT) nanocomposites were prepared via in situ polymerization by the dispersion of organically modified MMT in 11‐aminoundecanoic acid monomer. The polymorphic behavior of the nylon 11/MMT nanocomposites was investigated with X‐ray diffraction, transmission electron microscopy, and Fourier transform infrared with attenuated total reflectance. MMT induced and stabilized the δ‐crystalline form of nylon 11. The crystal structure of nylon 11 was transformed from a hexagonal δ‐form structure to a triclinic α‐form structure during the annealing process. Meanwhile, the hydrogen bonds in the nanocomposites also exhibited some differences from neat nylon 11 after annealing. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5483–5489, 2006
Synthesis and characterization of novel biodegradable poly(p‐dioxanone‐co‐ethyl ethylene phosphate)s
Authors: Li Feng , Feng Jun , Zhuo Renxi
Published: September 2006

Poly(p‐dioxanone‐co‐ethyl ethylene phosphate)s were successfully synthesized by the ring‐opening copolymerization of p‐dioxanone and ethyl ethylene phosphate with triisobutyl aluminum as an initiator; this was confirmed by 1H‐NMR and infrared spectra. The effects of the reaction conditions, such as the feeding ratio of the monomers and the reaction temperature and time, on the molecular weight of the copolymers were also studied. The in vitro degradation results showed that the introduction of phosphate segments into the backbone chains of the copolymers led to an enhancement of the degradation rate of the copolymers. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5507–5511, 2006
Effect of the delignification of wood fibers on the mechanical properties of wood fiber–polypropylene composites
Authors: Karimi Alinaghi , Nazari Saleh , Ghasemi Ismaeil , Tajvidi Mehdi , Ebrahimi Ghanbar
Published: September 2006

The effect of the delignification of hornbeam fibers on the mechanical properties of wood fiber–polypropylene (PP) composites was studied. Original fibers and delignified fibers at three levels of delignification were mixed with PP at a weight ratio of 40:60 in an internal mixer. Maleic anhydride (0.5 wt %) as the coupling agent and dicumyl peroxide (0.1 wt %) as the initiator were applied. The produced composites were then hot‐pressed, and specimens for physical and mechanical testing were prepared. The results of the properties of the composite materials indicate that delignified fibers showed better performance in the enhancement of tensile strength and tensile modulus, whereas the hardness of the composites was unaffected by delignification. Delignified fibers also exhibited better water absorption resistance. Notched impact strength was higher for delignified fiber composites, but it was reduced at higher delignification levels. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4759–4763, 2006