bluuebunny/crossref_metadata_2025 huggingface dataset:
Measures of Quality in Online Education: An Investigation of the Community of Inquiry Model and the Net Generation
Authors: Shea Peter , Bidjerano Temi
Published: April 2009

The goal of this article is to present and validate an instrument that reflects the Community of Inquiry Model (Garrison, Anderson, & Archer, 2000, 2001) and inquire into whether the instrument and the model it reflects explain variation in levels of student learning and satisfaction with online courses in a higher education context. Additionally this study sought to examine the effects of two other variables—age and students' registration status—on levels of satisfaction and learning in online courses. The issue of age and the “net generation” has generated considerable interest recently with a number of contradictory predictions made for younger students engaged in text-based, technology-mediated learning environments. Previous research indicates that student registration status serves as a relatively reliable predictor of commitment to degree and likely persistence in higher education (Horn & Neville, 2006)—does commitment to degree predict satisfaction and likely persistence with online learning in the same manner? We sought to inquire into the amount of variance these variables predict relative to constructs in the Community of Inquiry Framework. Results indicated that the instrument provides a coherent factor structure that reflects the Community of Inquiry Model. Other findings provide new insight into additional variables that account for variation in students' satisfaction, reported learning, and cognitive presence in text-based, asynchronous online environments.
Incentive Styles, Asynchronous Online Discussion, and Vocational Training
Authors: Lin Shinyi , Chiu Chou-Kang
Published: April 2009

Vocational education and training (VET) is intended to prepare adult learners for careers that are based on practical activities. With the underlying constructivist andragogy, this study intended to examine the effects of computer-mediated group collaboration in vocational education, and how that affects the associated learning outcomes. For collaborative learning, use of asynchronous computer-mediated communication as one of the major media prevails not only in web-based formats but in face-to-face. Specifically, our intent was to explore effectiveness of asynchronous online discussion (AOD) and the learning outcome accordingly. The results provided evidence that the participants in the AOD performed substantially better than those with no use of AOD in the bi-weekly quizzes as well as the learning outcomes. As incentive styles come into play, we found that the introverts performed as well as the extroverts disregarding the AOD participation. The results concluded that use of group collaboration as andragogical strategy (use of AOD) inferred better learning outcomes in the context of VET.
The Interpretative Flexibility, Instrumental Evolution, and Institutional Adoption of Mathematical Software in Educational Practice: The Examples of Computer Algebra and Dynamic Geometry
Authors: Ruthven Kenneth
Published: April 2009

This article examines three important facets of the incorporation of new technologies into educational practice, focusing on emergent usages of the mathematical tools of computer algebra and dynamic geometry. First, it illustrates the interpretative flexibility of these tools, highlighting important differences in ways of conceptualizing and employing them that reflect their appropriation to contrasting practices of mathematics teaching. Second, it examines the cultural process of instrumental evolution in which mathematical frameworks and teaching practices are adapted in response to new possibilities created by these tools, showing that such evolution remains at a relatively early stage. Third, it points to crucial prerequisites, at both classroom and systemic levels, for effective institutional adoption of such tools: explicit recognition of the interplay between the development of instrumental and mathematical knowledge, including the establishment of a recognized repertoire of tool-mediated mathematical techniques supported by appropriate discourses of explanation and justification.
Overexpression of GPR40 in Pancreatic β-Cells Augments Glucose-Stimulated Insulin Secretion and Improves Glucose Tolerance in Normal and Diabetic Mice
Authors: Nagasumi Kae , Esaki Ritsuko , Iwachidow Kimihiko , Yasuhara Yoshitaka , Ogi Kazuhiro , Tanaka Hideyuki , Nakata Mitsugu , Yano Takashi , Shimakawa Kozo , Taketomi Shigehisa , Takeuchi Koji , Odaka Hiroyuki , Kaisho Yoshihiko
Published: April 2009

OBJECTIVE

GPR40 is a G protein–coupled receptor regulating free fatty acid–induced insulin secretion. We generated transgenic mice overexpressing the hGPR40 gene under control of the mouse insulin II promoter and used them to examine the role of GPR40 in the regulation of insulin secretion and glucose homeostasis.

RESEARCH DESIGN AND METHODS

Normal (C57BL/6J) and diabetic (KK) mice overexpressing the hGPR40 gene under control of the insulin II promoter were generated, and their glucose metabolism and islet function were analyzed.

RESULTS

In comparison with nontransgenic littermates, hGPR40 transgenic mice exhibited improved oral glucose tolerance with an increase in insulin secretion. Although islet morphologic analysis showed no obvious differences between hGPR40 transgenic and nontransgenic mice, isolated islets from hGPR40 transgenic mice had enhanced insulin secretion in response to high glucose (16 mmol/l) compared with those from nontransgenic mice, and they both had similar low glucose (3 mmol/l)-stimulated insulin secretion. In addition, hGPR40 transgenic islets significantly increased insulin secretion against a naturally occurring agonist palmitate in the presence of 11 mmol/l glucose. hGPR40 transgenic mice were also found to be resistant to high-fat diet–induced glucose intolerance, and hGPR40 transgenic mice harboring KK background showed augmented insulin secretion and improved oral glucose tolerance compared with nontransgenic littermates.

CONCLUSIONS

Our results suggest that GPR40 may have a role in regulating glucose-stimulated insulin secretion and plasma glucose levels in vivo and that pharmacological activation of GPR40 may provide a novel insulin secretagogue beneficial for the treatment of type 2 diabetes.
Motor Proficiency Relationships among Siblings
Authors: Wrotniak Brian H. , Salvy Sarah J. , Lazarus Laura , Epstein Leonard H.
Published: April 2009

The purpose of this study was to examine motor proficiency relations of siblings. 23 sibling pairs ages 5 to 13 years were studied. Motor proficiency was assessed by the Bruininks-Oseretsky Test of Motor Proficiency-Short Form of 14 items, adjusting for Body Mass Index percentile, age, and sex. The association among siblings' overall motor proficiency was not statistically significant. When each of the 14 items in the test was examined separately, significant associations were found. Items positively associated among siblings included walking on a balance beam, tapping feet and making circles, and sorting shape cards. Copying a picture of overlapping pencils and making dots in circles were inversely related. The results indicate that siblings may share certain motor-skill components of balance, bilateral coordination, and upper limb speed or dexterity, but do not necessarily have the same global motor competence. Additional research is needed to explain relations in motor skills among siblings.
Personality Traits and Students' Misbehavior: Effects on French Physical Education Teachers' Anger Response
Authors: Ayme Sylvain , Ferrand Claude , Reynes Eric , Borteyrou Xavier
Published: April 2009

The aim was to assess intensities of State Anger over one week, reported by physical education teachers working in Education Priority Zone schools, to obtain descriptive data in diaries of these teachers' actions and reactions related to students' misbehavior. French physical education teachers ( N = 175) completed the Trait Anger Scale, the Trait Anxiety Inventory Form Y2, the Self-Esteem Scale, and the Depression Inventory. Cutoff scores on Trait Anger provided two groups (High Trait Anger, n = 44 and Low Trait Anger, n = 24). Participants ( N = 68) recorded State Anger and gave information about student misbehaviors in memorandums. Analysis showed mean State Anger was low. Participants' Trait Anger and personality correlates suggested they differed in reactions to students' misbehaviors. Findings were discussed in relation to the literature.
Effects of Digital Vibrotactile Speech Feedback on Overt Stuttering Frequency
Authors: Snyder Gregory J. , Waddell Dwight , Blanchet Paul , Ivy Lennette J.
Published: April 2009

Fluency-enhancing speech feedback, originating from internally or externally generated sources via auditory or visual sensory modalities is not restricted to a specific sensory modality or signal origination. Research suggests that externally generated digital vibrotactile speech feedback serves as an effective fluency enhancer. The present purpose was to test the fluency-enhancing effects of self-generated digital vibrotactile speech feedback on stuttering frequency. Adults who stutter read passages aloud over the telephone, both with and without digital vibrotactile speech feedback. Digital vibrotactile speech feedback was operationally defined as feeling the vibrations of the thyroid cartilage with the thumb and index finger while speaking. Analysis indicated that self-generated digital vibrotactile speech feedback reduced overt stuttering frequency by an average of 72%. As the specific neural mechanisms associated with stuttering and fluency enhancement from tactile speech feedback remain unknown, theoretical implications and clinical applications were discussed.
On Whether Mirror Neurons Play a Significant Role in Processing Affective Prosody
Authors: Ramachandra Vijayachandra
Published: April 2009

Several behavioral and neuroimaging studies have indicated that both right and left cortical structures and a few subcortical ones are involved in processing affective prosody. Recent investigations have shown that the mirror neuron system plays a crucial role in several higher-level functions such as empathy, theory of mind, language, etc., but no studies so far link the mirror neuron system with affective prosody. In this paper is a speculation that the mirror neuron system, which serves as a common neural substrate for different higher-level functions, may play a significant role in processing affective prosody via its connections with the limbic lobe. Actual research must apply electrophysiological and neuroimaging techniques to assess whether the mirror neuron systems underly affective prosody in humans.
Duration of Mentally Simulated Movement before and after a Golf Shot
Authors: Koyama Satoshi , Tsuruhara Kiyoshi , Yamamoto Yuji
Published: April 2009

This report examined the temporal consistency of preshot routines and the temporal similarity and variability between simulated movements before and after a shot. 12 male amateur golfers ages 32 to 69 years ( M = 53.4, SD = 10.5) were assigned into two groups according to their handicaps: skilled ( M = 4.0 handicap, SD = 3.1) and less-skilled ( M = 16.0 handicap, SD = 6.5). They performed their shots mentally from their preshot routines to the points when the balls came to rest, then performed the same shots physically and again recalled the shots mentally. For each of four par-three holes, participants' performances were filmed, and the durations of mental and actual shots were timed. Analysis showed that the skilled golfers had more consistent preshot routines in actual movement, and they also had longer durations for the ball flight phase than the less-skilled golfers in simulated movement. The present findings support the importance of consistent preshot routines for high performance in golf, however, the duration of simulated movements was underestimated both before and after the shots. This also suggests that skilled golfers attend to performance goals both before and after shots to execute their shots under proceduralized control and to correct their movements for their next shot.
Use of Imagery by Athletes in Nigeria
Authors: Adegbesan Olufemi Adegbola
Published: April 2009

Five types of imagery used by 188 Nigerian athletes in track and field, soccer, and table tennis were examined using the Sport Imagery Questionnaire [ M age for men 24.7 yr. ( SD = 3.6) and for women 23.3 yr. ( SD = 3.4)] to assess whether these participants differed in their use of imagery. Significant differences were noted for the three sports on subscales of Cognitive General, Motivational Specific, Motivation General-Mastery, and Motivation General-Arousal, while moderate to strong positive correlations were identified among scores on imagery subscales, especially Motivation General-Mastery and Motivation General-Arousal. Cronbach α for the questionnaire was suitable for all subscales but one.
A Taoist Orientation and Fears of Death and Dying
Authors: Zeyrek Emek Yüce , Lester David
Published: April 2009

In samples of 100 Turkish undergraduates and 87 American undergraduates, having a Taoist orientation was not consistently associated with fear of death and dying.
Comparative Study of Digit Ratios (2D:4D and Other) and Novel Measures of Relative Finger Length: Testing Magnitude and Consistency of Sex Differences across Samples
Authors: Voracek Martin
Published: April 2009

Digit ratios, such as the frequently studied second-to-fourth digit ratio (2D:4D), are already sexually differentiated in utero, postnatally fairly stable, and thus commonly held as possible markers for prenatal androgen levels. Based on six independent samples, totaling 381 male and 420 female subjects from different age bands, this study investigated the magnitude and cross-sample consistency of sex differences in all six possible digit ratios (2D:3D, 2D:4D, 2D:5D, 3D:4D, 3D:5D, 4D:5D) and in four novel relative finger-length measures (the ratio of a given finger to the sum of all four fingers) that were recently suggested by Loehlin, Medland, and Martin as possibly superior to digit ratios for discriminating between the sexes. However, based on the magnitude of sex effects and observed measurement repeatabilities, these novel measures were not superior to digit ratios. Across samples, among digit ratios the traditionally used 2D:4D never yielded the largest sex effect, 2D:5D was the most and 2D:3D the least sexually differentiated. Sex differences were generally larger for digit ratios calculated from nonadjacent than from adjacent fingers. Compared with females, males' relative finger length was clearly lower for 2D, somewhat lower for 3D, somewhat higher for 4D, and clearly higher for 5D. This gradient suggests mediolaterally arranged developmental fields that act sexually differentiated on finger-length expression. Implications of these findings for further digit ratio research are discussed.
Lipid Profile and Clinical Characteristics of Women with Gestational Diabetes Mellitus and Preeclampsia
Authors: McGrowder Donovan , Grant Kevin , Irving Rachael , Gordon Lorenzo , Crawford Tazhmoye , Alexander-Lindo Ruby , Pena Fraser Yeiny
Published: April 2009

Lipid Profile and Clinical Characteristics of Women with Gestational Diabetes Mellitus and Preeclampsia

Gestational diabetes mellitus (GDM) is associated with increased risk of pregnancy-induced hypertension and other maternal and foetal complications of pregnancy. The aims of the study were to evaluate the serum lipid profile of women with GDM, and determine the number of women with GDM who have preeclampsia (PE). A retrospective study of 84 women with GDM and 90 pregnant women with normal glucose tolerance (controls) was conducted. Women with GDM had significantly higher parity (p=0.047), total cholesterol (p=0.039) and triglycerides (p=0.033), but non-significantly lower HDL-cholesterol (p=0.086) when compared to controls. Systolic blood pressure was significantly elevated in women with GDM coupled with PE (GDM-PE; p=0.015), the mean birth weight of infants born to women with GDM-PE was significantly lower than that of women with only GDM (p=0.025). Women with GDM-PE had significantly higher triglycerides (p=0.020), had to be more multi-gravida (p=0.047) with significantly elevated VLDL-cholesterol (p=0.037) when compared with women with only GDM. 11.9% of women with GDM had PE. On the basis of these findings, it can be concluded that GDM is associated with hyperlipidaemia as evident by the significantly elevated total cholesterol and triglyceride concentrations. Women with dyslipidaemia and GDM are at risk of developing preeclampsia. It is imperative that blood lipids be evaluated in women with GDM during antenatal care as it would be helpful in the early detection and treatment of PE.
Evaluation of Coronary Risk Score Applications in 10-Year Coronary Heart Risk Estimation
Authors: Eremić Nevena , Đerić Mirjana
Published: April 2009

Evaluation of Coronary Risk Score Applications in 10-Year Coronary Heart Risk Estimation

Atherosclerosis is a multifactorial disease with risk factors that have multiple effects. In the identification and treatment of asymptomatic individuals at high risk for developing coronary heart disease (CHD) different risk scoring schemes are used in everyday routine. The aim of this study was to compare SCORE recommended for our country with two other most frequently used risk schemes for 10-year CHD risk evaluation: Framingham and PROCAM as well as their modifications. From 220 examined subjects of both sexes, who were treated mainly for lipid metabolism disorder at the Dispensary for Atherosclerosis Prevention, Centre for Laboratory Medicine, Clinical Centre of Vojvodina, 110 subjects were included in our study and agreed to a one-year follow-up. At first check-up, 15% had low risk according to Framingham Weibull and 78% according to PROCAM, intermediate 12% according to PROCAM NS up to 45% according to Framingham Weibull, and high 8% according to PROCAM up to 40% according to Framingham Weibull. After a one-year treatment 30% were in the low risk category according to Framingham Weibull and 88% according to PROCAM. Intermediate from 10% according to PROCAM to 36% according to Framingham Weibull, and high from 2% according to PROCAM to 25% according to Framingham Weibull. There is a significantly lower percentage of high risk individuals and a higher percentage of low risk individuals after one year of lipid disorder treatment.
Ghostwriting Transnational Histories in Michelle Cliff's Free Enterprise
Authors: Johnson Erica L.
Published: April 2009

In this article I argue that Cliff's portrait of the nineteenth-century African American abolitionist, entrepreneur, and civil rights activist Mary Ellen Pleasant participates in a genre of subaltern historiography that I term “ghostwriting.” Cliff was inspired to write about Pleasant, who provided major funding and leadership in John Brown's raid on Harper's Ferry in 1859—and indeed the stone that marks her grave reads simply: “M. E. P. She was a friend of John Brown”—because her role in the raid and in U.S. abolition is absent from nearly all historical documentation. I open the essay with the fact of Pleasant's erasure by documenting her historiographical absence and then go on to explain how Cliff ghostwrites Pleasant's story through a narrative of strategic adjacencies. Cliff enmeshes Pleasant's story with those of others engaged in contrapuntal history-telling from all over the world. This transnational network of resistance extends in Cliffs novel from the Caribbean to the Pacific to Sephardic passageways; her character bears witness to events from the Spanish Inquisition to the Civil Rights era in the U.S., a temporal span that Cliff achieves through the dynamic of haunting. Through her emphasis on the power of mutual witnessing and her use of a Decameronian plot structure, Cliff acts as a ghostwriter by first telling another person's story and, more importantly, by recounting stories of largely absent and hence ghostly subjects.
The Formation of a Chinese Immigrant Working-class Patriarchy
Authors: Shi Yu
Published: April 2009

Based on ethnographic fieldwork in the San Francisco Bay area, this study traces the emergence of a Chinese immigrant working-class patriarchy that is enabled by the articulation of “traditional” Chinesefemininity with new or reinvented gendered expectations in immigrant settings. I argue that the emergence and configuration of this patriarchy demonstrates the flexibility of patriarchal ruling. Its formation of new gendered expectations in immigrant settings by no means indicates that the “old” values from the homeland, such as chastity, self-sacrifice, and self abnegation, have become obsolete upon migration, or that these gendered expectations are uniquely “ethnic Chinese.” On the contrary, the “old” values are reinvented and invoked by the Chinese immigrant working-class patriarchy to build and sustain its power in U.S. society. Therefore, this patriarchy also implicates the structural patriarchy and the racial and class inequalities of the host society. Finally, I contend that various patriarchal hegemonies—East or West, American or Chinese, ethnic or mainstream, traditional or contemporary—should be interpreted in a way that illuminates not just their uniqueness but also their internal connections, mutual constitutions, and constant negotiations.
An African Queen at the Philadelphia Centennial Exposition 1876
Authors: Woods Naurice Frank
Published: April 2009

Mary Edmonia Lewis (ca. 1843–after 1909) was America's first professional sculptor of African and Native American descent. She staked a claim at the highest level of neoclassical art. This usually meant competing against men who vehemently opposed women competing in a “man's” profession. Lewis found the fortitude to take up the challenge and, along with several other women (all white), demonstrated the capacity to produce extraordinary marble sculptures. Lewis's burden was twofold. In addition to her gender, her race presented unique obstacles, especially to those who subscribed to the belief that those with a “drop of African blood” were rendered less intelligent and creatively inept. Her crowning achievement was The Death of Cleopatra (1876) that was exhibited at the Philadelphia Centennial Exhibition of 1876 to great acclaim. This paper offers critical insights into the creation of that great work.
Biocompatibility of Resin-based Dental Materials
Authors: Moharamzadeh Keyvan , Brook Ian , Van Noort Richard
Published: April 2009

Oral and mucosal adverse reactions to resin-based dental materials have been reported. Numerous studies have examined thebiocompatibility of restorative dental materials and their components, and a wide range of test systems for the evaluation of the biological effects of these materials have been developed. This article reviews the biological aspects of resin-based dental materials and discusses the conventional as well as the new techniques used for biocompatibility assessment of dental materials.
Development of a Sensor Node for Precision Horticulture
Authors: López Juan  A. , Soto Fulgencio , Sánchez Pedro , Iborra Andrés , Suardiaz Juan , Vera Juan  A.
Published: April 2009

This paper presents the design of a new wireless sensor node (GAIA Soil-Mote) for precision horticulture applications which permits the use of precision agricultural instruments based on the SDI-12 standard. Wireless communication is achieved with a transceiver compliant with the IEEE 802.15.4 standard. The GAIA Soil-Mote software implementation is based on TinyOS. A two-phase methodology was devised to validate the design of this sensor node. The first phase consisted of laboratory validation of the proposed hardware and software solution, including a study on power consumption and autonomy. The second phase consisted of implementing a monitoring application in a real broccoli (Brassica oleracea L. var Marathon) crop in Campo de Cartagena in south-east Spain. In this way the sensor node was validated in real operating conditions. This type of application was chosen because there is a large potential market for it in the farming sector, especially for the development of precision agriculture applications.
Jesus Christ as ancestor: An African Christian understanding
Authors: Beyers Jaco , Mphahlele Dora N.
Published: April 2009

Jesus Christ, the Son of God, Son of Man, Son of David, Lord (Kyrios), Rabbi and Messiah. These are some of the names used by Christians today and even by the people from the era of Jesus Christ to address him or to communicate with him. Others use them because they were taught that this is the way you talk about him or to him. People use all these different names to describe Jesus Christ according to their understanding, knowledge, trust and belief in him. This article will describe how the Sotho, who are African Christians, from the township of Mohlakeng in Randfontein, know, understand, trust and believe in Jesus Christ according to the title of Great Ancestor. Views of the inhabitants of Mohlakeng are used to describe the complexity of the issue. This article discusses what the meaning of the concept of ancestor entails and determines whether Jesus can indeed be referred to as Ancestor. There are different answers to this question.
Balancing dual roles in self-employed women: An exploratory study
Authors: McLellan Kirsty-Lee , Uys Koos
Published: April 2009

This study is aimed at exploring how self-employed women cope in balancing their dual roles as mothers and executives. Through the elicitation of constructs by making use of Kelly’s repertory grid technique, the personal construct system of five self-employed white women in Gauteng across varying industries was established. While being successful dual earners, they still bore the primary responsibility for nurturing their families and assuring their well-being. The successful balancing of their dual roles was attributed to the following central themes, which emerged from all the participants: quality time spent with children and family, structure and planning, coping with guilt, support structures and self-reliance, and balance between work and life.
Resistance to the influences of others: Limits to the formation of a collective memory through conversational remembering
Authors: Muller Felipe , Hirst William
Published: April 2009

People often form collective memories by sharing their memories with others. Warnings about the reliability of one conversational participant can limit the extent to which conversations or other forms of postevent information can influence subsequent memory. Although this attenuation is consistently found for prewarnings, there are substantial reasons to suspect that, by carefully manipulating both individual characteristics of the listener in a conversation and the dynamics of the postevent conversation, one can restrict the effect even prewarnings have on the influence a speaker might have on the memory of a listener. Indeed, in situations in which a speaker contributes substantially to a conversation and the quality of memory of a listener is poor, prewarnings have the paradoxical effect of increasing the influence of the speaker on a listener's memory. Warnings may not always limit the formation of a collective memory. Copyright © 2009 John Wiley & Sons, Ltd.
Measurements by MRI of the settling and packing of solid particles from aqueous suspensions
Authors: Acosta‐Cabronero Julio , Hall Laurance D.
Published: April 2009

This study extends the application of existing magnetic resonance imaging methods to measure the settling of solid particles from aqueous suspensions. The acquisition of one‐dimensional multiecho projections allowed the direct measurement of initial magnetizations (M0), from which solid volume fractions along the sedimentation column were inferred. For polystyrene beads, it was found that monoexponential curves accurately fitted the transverse relaxation decays. In contrast, for the other four solids investigated (activated carbon, talc, calcium carbonate, and glass beads), the single exponential model did not suffice and additional terms in the fitting function significantly improved the calculation of solid concentrations. Additional information about particle sizes was obtained by comparing volume fractions with the spin–spin relaxation times of the hydrogen protons as a function of the vertical height through the sedimenting suspensions of activated carbon and polystyrene beads. © 2009 American Institute of Chemical Engineers AIChE J, 2009
Effect of sample size on microwave power absorption within dielectric materials: 2D numerical results vs. closed‐form expressions
Authors: Curet S. , Rouaud O. , Boillereaux L.
Published: April 2009

This study deals with the analytical and numerical solutions of the heat source term because of microwave heating for high and low dielectric materials in 1D and 2D configurations. The authors compare closed‐form expressions dedicated to microwave power calculation to numerical simulations. A comprehensive and accurate analysis of the microwave power reflected from the surface of the sample is also carried out during microwave heating. The influence of sample length is studied using an original numerical procedure. The study highlights that 1D closed‐form expressions can be extended to 2D configurations in the case of sufficiently high dielectric properties. Examples of heating rate during 2D microwave heating in TE10 mode are finally presented. © 2009 American Institute of Chemical Engineers AIChE J, 2009
Control of the morphology and the size of complex coacervate microcapsules during scale‐up
Authors: Lemetter C. Y. G. , Meeuse F. M. , Zuidam N. J.
Published: April 2009

Scale‐up of complex coacervation, a fat encapsulation technology, is not trivial since the microcapsules morphology and size are highly affected by the processing conditions. So far it has been achieved empirically (trial and error approach). The goal of this study was to produce at various scale capsules with a single‐oil droplet as the core material and small enough to be below sensory threshold. The turbulence level was identified as the main scale‐up criterium and a master‐curve could be drafted showing the capsule mean diameter as function of the Reynolds number, independent of the level of production scale. From a parent emulsion with specific oil droplets size (12–15 μm), the Reynolds number had to be maintained above a critical value (15,000) to avoid capsules agglomeration with multiple oil cores and large particle sizes. To avoid aggregation, this turbulence level had to be kept until the temperature dropped below a critical value (14°C for a cooling rate of 35°C/2 h). Applying these learning led to a successful scale‐up from bench (2 L) to a pilot plant scale of 50 L. © 2009 American Institute of Chemical Engineers AIChE J, 2009
Dynamic optimization of the methylmethacrylate cell‐cast process for plastic sheet production
Authors: Rivera‐Toledo Martín , Flores‐Tlacuahuac Antonio , Vílchis‐Ramírez Leopoldo
Published: April 2009

Traditionally, the methylmethacrylate (MMA) polymerization reaction process for plastic sheet production has been carried out using warming baths. However, it has been observed that the manufactured polymer tends to feature poor homogeneity characteristics measured in terms of properties like molecular weight distribution. Nonhomogeneous polymer properties should be avoided because they give rise to a product with undesired wide quality characteristics. To improve homogeneity properties force‐circulated warm air reactors have been proposed, such reactors are normally operated under isothermal air temperature conditions. However, we demonstrate that dynamic optimal warming temperature profiles lead to a polymer sheet with better homogeneity characteristics, especially when compared against simple isothermal operating policies. In this work, the dynamic optimization of a heating and polymerization reaction process for plastic sheet production in a force‐circulated warm air reactor is addressed. The optimization formulation is based on the dynamic representation of the two‐directional heating and reaction process taking place within the system, and includes kinetic equations for the bulk free radical polymerization reactions of MMA. The mathematical model is cast as a time dependent partial differential equation (PDE) system, the optimal heating profile calculation turns out to be a dynamic optimization problem embedded in a distributed parameter system. A simultaneous optimization approach is selected to solve the dynamic optimization problem. Trough full discretization of all decision variables, a nonlinear programming (NLP) model is obtained and solved by using the IPOPT optimization solver. The results are presented about the dynamic optimization for two plastic sheets of different thickness and compared them against simple operating policies. © 2009 American Institute of Chemical Engineers AIChE J, 2009
Early reproductive maturity among Pumé foragers: Implications of a pooled energy model to fast life histories
Authors: Kramer Karen L. , Greaves Russell D. , Ellison Peter T.
Published: April 2009

Life history theory places central importance on relationships between ontogeny, reproduction, and mortality. Fast human life histories have been theoretically and empirically associated with high mortality regimes. This relationship, however, poses an unanswered question about energy allocation. In epidemiologically stressful environments, a greater proportion of energy is allocated to immune function. If growth and maintenance are competing energetic expenditures, less energy should be available for growth, and the mechanism to sustain rapid maturation remains unclear. The human pattern of extended juvenile provisioning and resource sharing may provide an important source of variation in energy availability not predicted by tradeoff models that assume independence at weaning. We consider a group of South American foragers to evaluate the effects that pooled energy budgets may have on early reproduction. Despite growing up in an environment with distinct seasonal under‐nutrition, harsh epidemiological conditions, and no health care, Pumé girls mature quickly and initiate childbearing in their midteens. Pooled energy budgets compensate for the low productivity of girls not only through direct food transfers but importantly by reducing energy they would otherwise expend in foraging activities to meet metabolic requirements. We suggest that pooled energy budgets affect energy availability at both extrinsic and intrinsic levels. Because energy budgets are pooled, Pumé girls and young women are buffered from environmental downturns and can maximize energy allocated to growth completion and initiate reproduction earlier than a traditional bound‐energy model would predict. Am. J. Hum. Biol., 2009. © 2009 Wiley‐Liss, Inc.
A CDKL5 mutated child with precocious puberty
Authors: Saletti Veronica , Canafoglia Laura , Cambiaso Paola , Russo Silvia , Marchi Margherita , Riva Daria
Published: April 2009

To date, 43 patients have been described with mutations in or involving the CDKL5 gene. The typical phenotype includes early‐onset, often intractable epileptic seizures and severe mental retardation with very limited progress in psychomotor development. Most patients also show impaired social interaction with avoidance of eye‐to‐eye contact, and some clinical features reminiscent of Rett syndrome (RTT), including stereotypic hand movements, lack of purposeful hand use, acquired microcephaly, and generalized hypotonia. We report on the case of a 5‐year‐old girl with a de novo CDKL5 gene mutation who developed early puberty, which has not been described before. © 2009 Wiley‐Liss, Inc.
“On‐Off” Multivalent Recognition: Degradable Dendrons for Temporary High‐Affinity DNA Binding
Authors: Welsh Daniel J. , Jones Simon P. , Smith David K.
Published: April 2009

Jetzt binden – jetzt nicht! Durch chemischen Abbau eines dendritischen Gerüsts, d. h. das Aufbrechen einer multivalenten Ligandenanordnung in kleinere Fragmente, können multivalente Wechselwirkungen mit DNA „ausgeschaltet“ werden, wodurch ein Molekül temporär mit einer hohen Affinität für ein biologisches Ziel versehen werden kann. Dieses Konzept ist von Bedeutung für die Entwicklung neuer synthetischer Systeme, die in biologische Abläufe eingreifen.

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Interactive Radical Dimers in Photoconductive Organic Thin Films
Authors: Iwasaki Akito , Hu Laigui , Suizu Rie , Nomura Kenji , Yoshikawa Hirofumi , Awaga Kunio , Noda Yukiko , Kanai Kaname , Ouchi Yukio , Seki Kazuhiko , Ito Hiroshi
Published: April 2009

Überlappende ausgedehnte unbesetzte Molekülorbitale haben eine hohe Photoleitfähigkeit wechselwirkender Radikaldimere zur Folge. Sandwich‐Zellen (siehe Bild; ITO=Indiumzinnoxid) mit hochorientierten dünnen Filmen des nichtkonjugierten Diradikals 4,4′‐Bis(1,2,3,5‐dithiadiazolyl) (BDTDA) liefern einen Photostrom mit hohem An/Aus‐Verhältnis bei Sperrvorspannungen und verhalten sich photovoltaisch bei einer Vorspannung von null.

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A Convenient Method for the Synthesis of α‐Ethynylphospholes and Modulation of Their π‐Conjugated Systems
Authors: Matano Yoshihiro , Nakashima Makoto , Imahori Hiroshi
Published: April 2009

Lücken nach Wunsch: α‐Ethinylphosphole, die in situ aus den entsprechenden silylierten Vorstufen erzeugt wurden, lieferten eine Serie von α‐(Arylethinyl)phospholen mit funktionellen Substituenten sowie ein α,α′‐verknüpftes Terphosphol (siehe Schema), das wegen der effizienten π‐Konjugation über drei Phospholringe eine schmale HOMO‐LUMO‐Lücke aufweist.

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Modern Supramolecular Gold Chemistry.Gold–Metal Interactions and Applications. Herausgegeben von A. Laguna.
Authors: Puddephatt Richard J.
Published: April 2009

Wiley‐VCH, Weinheim 2008. 505 S., geb., 159.00 €.—ISBN 978‐352732095

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The Power of Functional Resins in Organic Synthesis.Herausgegeben von Judit Tulla‐Puche und Fernando Albericio.
Authors: Breinbauer Rolf
Published: April 2009

Wiley‐VCH, Weinheim 2008. 663 S., geb., 159.00 €.—ISBN 978‐3527319367

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Direct CC Cross‐Coupling of Secondary and Primary Alcohols Catalyzed by a γ‐Alumina‐Supported Silver Subnanocluster
Authors: Shimizu Ken‐ichi , Sato Ryosuke , Satsuma Atsushi
Published: April 2009

Zum Wohl! Zwei Alkohole (ein primärer und ein sekundärer) werden mithilfe eines Katalysesystems in Form von Silber‐Subnanoclustern auf γ‐Al2O3 durch Wasserstoffautotransfer atomeffizient gekuppelt. Der wiederverwendbare Heterogenkatalysator fördert die Eintopf‐C‐C‐Kreuzkupplung in Gegenwart katalytischer Mengen der schwachen Base Cs2CO3 (siehe Reaktionsmechanismus).

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A Bis(silaselenone) with Two Donor‐Stabilized SiSe Bonds from an Unexpected Stereoconvergent Hydrolysis of a Diselenadisiletane
Authors: Mitra Amitabha , Wojcik Joseph P. , Lecoanet Daniel , Müller Thomas , West Robert
Published: April 2009

SiSe matters: Diselenadisiletane 2, formed from direct reaction of a racemic silylene 1 with elemental selenium, gives the first bis(silaselenone) upon hydrolysis with water (3; see picture, C gray, H white, N blue, O red, Se purple, Si green; d(SiSe)=215 pm). The reaction is stereoconvergent: only racemic forms of 3 are obtained from a mixture of racemic and meso forms of 2.

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Platinum(II)‐Catalyzed Intramolecular Cyclization of o‐Substituted Aryl Alkynes through sp3 CH Activation
Authors: Yang Shangdong , Li Zigang , Jian Xing , He Chuan
Published: April 2009

Ring leader: PtCl2 catalyzes intramolecular cyclization of o‐isopropyl or o‐benzyl aryl alkynes to give substituted indene derivatives with good yields and high selectivity. This reaction appears to proceed through an sp3 CH activation and 1,4‐hydrogen migration pathway (see scheme).

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“On‐Off” Multivalent Recognition: Degradable Dendrons for Temporary High‐Affinity DNA Binding
Authors: Welsh Daniel J. , Jones Simon P. , Smith David K.
Published: April 2009

Now you bind it—now you don't! Chemical degradation of a dendritic scaffold allows multivalent interactions with DNA to be “switched off” as the multivalent array of ligands breaks down into smaller fragments, offering an approach by which a molecule can be temporarily endowed with high affinity for a biological target—an important concept in the development of new synthetic systems to intervene in biological pathways.

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The Power of Functional Resins in Organic Synthesis.Edited by Judit Tulla‐Puche and Fernando Albericio.
Authors: Breinbauer Rolf
Published: April 2009

Wiley‐VCH, Weinheim 2008. 663 pp., hardcover € 159.00.—ISBN 978‐3527319367

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Inside Cover: Challenging the Metallocene Dominance in Actinide Chemistry with a Soft PNP Pincer Ligand: New Uranium Structures and Reactivity Patterns (Angew. Chem. Int. Ed. 20/2009)
Authors: Cantat Thibault , Graves Christopher R. , Scott Brian L. , Kiplinger Jaqueline L.
Published: April 2009

A standing iceberg illustrates how the soft PNP pincer ligand challenges the metallocene dominance (ship) in actinide chemistry, as described by J. L. Kiplinger and co‐workers in their Communication on page 3681 ff. Replacement of C5Me5 by the PNP ligand is a successful strategy for the promotion of new reactivities and to support new actinide structures. The specific electronic and steric properties of the PNP ligand enable access to structures not available for the C5Me5 ligand set and as yet unreported for uranium. (We thank Mr. Anthony Mancinco for the design of the graphic.)

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Anti‐thrombogenicity of styrene‐butadiene‐styrene triblock copolymer grafted with poly(ethylene glycol)s
Authors: Nagura Masanobu , Nomura Yasutoshi , Gotok Yasuo , Ckkosti Yutaka
Published: April 2009

We transformed hydrophobic/hydrophobic styrene/butadiene/styrene tri‐block copolymer (SBS) to hydrophobic / hydrophilic microphase‐separated surfaces by grafting with hydrophilic poly(ethylene glycol) (PEG) on poly(butadiene) (PB) domain via hydrocarboxylation and hydrobromination and investigated the anti‐thrombogenicity of these surfaces. In the case of SBS cast film from toluene solution, PEG was densely grafted because of the development of an unevenness on the order of several 10 nm on the surface, which had a huge surface area in comparison with poly(butadiene) rubber with its uniformly smooth surface. Grafted PEG (molecular weight = 600) was found to clearly inhibit adhesion and activation of platelets and coagulation of the whole blood component, which is indicative of anti‐thrombogenicity. These properties correspond to a surface coated by a copolymer of 2‐methacryloyl‐oxyethyl phosphorylcholine and n‐butyl methacrylate, which is well known to be the best excellent anti‐thrombogenic material in the world. Melt‐molded SBS film, which also has an uneveness on the order of several 10 nm, showed similar excellent anti‐thrombogenicity. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Preparation of poly(acrylonitrile–butadiene–styrene)/montmorillonite nanocomposites and degradation studies during extrusion reprocessing
Authors: Karahaliou E.‐K. , Tarantili P. A.
Published: April 2009

In this study, the preparation of organically modified montmorillonite/poly(acrylonitrile–butadiene–styrene) (ABS) nanocomposites was studied by melt blending in a twin‐screw extruder. The composite material was subjected to a series of five extrusion cycles, and the effect of reprocessing on the material's structural properties was investigated. More specifically, chemical changes were studied with attenuated total reflectance/Fourier transform infrared analysis, the thermal response was recorded by differential scanning calorimetry experiments, and the thermal stability was detected with thermogravimetric analysis. Also, the rheological properties of these blends were investigated via melt flow index tests as a measure of their processability during melt mixing and molding processes. Furthermore, the mechanical strength of the obtained mixtures was explored, and the observed interactions were interpreted in terms of the influence of each component on the functional properties of the final mixture. This attempt enriched our knowledge about the recycling of ABS, with the additional aspect of the use of collected data from more complex systems, that is, composite materials, where the montmorillonite nanoparticles play a role in the interactions initiated by repeated processing. The experimental results of this study show that the reprocessing of ABS/montmorillonite induced oxidation products, but the rheological, mechanical, and thermal properties and the thermal and color stabilities of the composites remained almost stable. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Mechanical properties of Bombyx mori silk yarns studied with tensile testing method
Authors: Aksakal Baki , Tsobkallo Ekaterina , Darvish Diana
Published: April 2009

The mechanical properties of Bombyx mori silk yarns and baves were investigated with tensile testing method. After silk yarns were pre‐extended at different strain levels and fixed for a while followed by recovery process, the tensile characteristics were examined in detail. It was commonly observed that low preliminary extensions up to 2–3% do not cause the changes of the mechanical properties and stress‐strain curves because they result in small structural changes and distortions, which were recovered within relatively short time (∼ 1 min) in recovery process. However, pre‐extension values >3% strain lead to great changes of the mechanical properties and fibre structure, i.e., the changes of the shape of stress‐strain curve where additional transition point was observed, increase in the rigidity and stress at rupture, but decrease in extensibility as a result of orientation and destruction of the fibre structure especially in the amorphous region. It was stated that silk fibre consists of two distinct deformation regions, namely first linear region extending up to 2–3% strain and the second region beyond 2–3% strain where the main reorganization processes of the fibre structure, that is, the straining of macromolecular chains especially in the amorphous regions, the orientation of structural units such as β‐sheet microcrystals in stretching direction, and the destruction of macromolecules take place. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Increasing hydration of the epidermis by microcapsules in sterilized products
Authors: Gisbert J. , Ibañez F. , Bonet M. , Monllor P. , Díaz P. , Montava I.
Published: April 2009

Some nonserious skin infections can be treated by hydration and antibacterial control. Microcapsules containing aloe‐chitin are often used to treat this kind of problem. Microcapsules were applied to cotton fabrics by padding and sleeves were prepared. A hypoallergenic test was applied to the microcapsule emulsion and hydration of the epidermis was evaluated by capacitance methods. The fabric was sterilized by electron beam treatment to satisfy the antibacterial requisite. The results showed that the aloe is transferred from the fabric to the skin, increasing the level of skin hydration. The electron beam method was also shown to be effective for bacteria and fungi and had no effect on the microcapsule properties. It can, therefore, be confirmed that electron beam sterilization has no harmful effects on the type of microcapsule used in this study. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009