bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization of the crustose red alga Peyssonnelia japonica (Rhodophyta, Gigartinales) and its taxonomic relationship with Peyssonnelia boudouresquei based on morphological and molecular data
Authors: Kato Aki , Guimarães Silvia M. P. B. , Kawai Hiroshi , Masuda Michio
Published: February 2009

The vegetative and reproductive morphology of the crustose red alga Peyssonnelia japonica (Segawa) Yoneshigue was re‐examined based on the holotype specimen and recent collections from various localities in Japan, including the type locality, and Hawaii. This species is characterized by the following features: thallus with appressed margins, perithallial filaments arising from the entire upper surface of each hypothallial cell (the Peyssonnelia rubra‐type), easily separable perithallial filaments in a gelatinous matrix, hypothallial filaments arranged in parallel rows, unicellular rhizoids, hypobasal calcification, gonimoblasts derived mainly from connecting filaments, and spermatangia produced in a series of whorls comprised of one to four paired spermatangia surrounding each central cell (the Peyssonnelia dubyi‐type). In addition to these features, the dimensions of the vegetative and reproductive structures of Peyssonnelia boudouresquei Yoneshigue described from Brazil were consistent with those of P. japonica. Molecular phylogenetic analyses using partial 26S rDNA, rbcL, and cox2‐3 spacer DNA sequences also supported the monophyly of P. japonica (from 16 localities in Japan and one locality in Hawaii) and P. boudouresquei (from two localities in Brazil). Therefore, P. boudouresquei may be a taxonomic synonym of P. japonica. However, considering the relatively high sequence divergences between the two taxa (2.1–2.5% in partial 26S rDNA, 5.9–6.7% in rbcL, and 5.8–6.7% in cox2‐3 spacer), and the relatively limited geographic sampling ranges, we reserve the taxonomic conclusion until further morphological and genetic data of the specimens from other geographic areas connecting Japan and Brazil become available.
Computerized tomographic finding of saddle pulmonary embolism is associated with high mortality in cancer patients
Authors: Yusuf S. W. , Gladish G. , Lenihan D. J. , Lei X. , Durand J.‐B. , Swafford J. , Daher I. N.
Published: February 2009

Background: Large pulmonary embolism (PE) is associated with high mortality in cancer patients. Several risk stratification methods have been used in PE setting. While computer‐assisted tomography (CT) is now the preferred diagnostic modality for PE, its prognostic value is not well established.

Methods: A retrospective study of patients discharged from our centre between 2000 and 2006 with a PE diagnosis identified 52 patients with thrombus in the main pulmonary artery or the right or left branch. Clinical, echocardiographic and CT data were reviewed; vital status was determined 1 month and 1 year after index event. Patients were divided into saddle (defined as main pulmonary artery thrombus) and non‐saddle PE. Multivariate logistic regression was applied to predict vital status, with patient age and CT parameters as predictors.

Results: Eighteen out of 52 patients were found to have a saddle PE. No significant difference was found between the group characteristics, although saddle PE patients were more likely to receive thrombolytic therapy (27.8% vs 2.9%, P = 0.02) and have an echocardiogram within 30 days of PE (61.1% vs 29.4%, P = 0.03). Overall mortality at 1 month was 9.6% with no difference between groups. At 1 year, mortality rates in saddle PE were significantly higher (83.3% vs 41.2%, P = 0.004). Presence of saddle PE was associated with an odds ratio of death within 1 year of 7.41 (95% confidence interval: 1.75–31.46, P = 0.007).

Conclusion: The relatively simple distinction of saddle versus non‐saddle PE by CT findings may provide a straightforward method for risk stratification, and remains useful up to 1 year after the index event.
Evaluation of fatigue life of aluminium alloy wheels under bending loads
Authors: RAJU P. RAMAMURTY , SATYANARAYANA B. , RAMJI K. , BABU K. SURESH
Published: February 2009

This paper presents the details of S–N curve for aluminium alloy (Al) A356.2‐T6 and fatigue life of alloy wheels under bending load of cornering fatigue test (CFT). Development of S–N curve has been carried out by conducting rotary bending fatigue test at different stress levels as per Standards IS 5075. The rotary bending fatigue test has been performed under constant amplitude fatigue loading. The CFT of the wheel in normal driving mode has been carried out as per the procedure given in Japanese Industrial Standard Disc Wheels (JIS D_4103). It has been observed from the test that the cracks are initiated at the spoke and hub joining area closer to spanner hole on the front face of the wheel. Fatigue life of the alloy wheel has been predicted by finite element analysis (FEA), simulating the realistic test conditions. From finite element analysis, it has been observed that the maximum stress occurs at the mounting face of the wheel. Further, it has been observed that there is significant difference between the computed fatigue life and experimental value. Parametric study has been carried out for reliable fatigue life estimation and proposed an appropriate safety factor for fatigue life estimation under rotary bending test.
Impact and tensile properties of ferrite–martensite dual‐phase steels
Authors: ISFAHANI T. DALALLI , SHAFYEI A. , SHARIFI H.
Published: February 2009

The effect of martensite morphology on the impact and tensile properties of dual phase steels with a 0.25 volume fraction of martensite (Vm) under different heat treatments was investigated. These treatments are direct quenching (DQ) and step quenching (SQ) that result in different microstructures and mechanical properties. To process dual phase steels, a low carbon manganese steel was used. At first the banding present in the initial steel was eliminated, then the two different heat treatments were applied. To reach a 0.25 volume fraction of martensite a variation of intercritical annealing temperatures was adopted for both treatments that allowed the evolution of different volume fraction of martensite. Phase analysis showed that an intercritical temperature of 725 °C (between A3, A1) gives the desired 0.25 Vm of martensite. A comparison of impact, tensile and ductile–brittle transition temperature (DBTT) indicates that the microstructure of the direct treatment has a better toughness. The DBTT for the DQ and SQ treatment is −49 and −6 °C, respectively.
Investigation of fracture characterizations of functionally graded materials
Authors: YAO X. F. , LIU D. L. , XU H. M. , YEH H. Y.
Published: February 2009

In this paper, the mode I crack problem of functionally gradient materials (FGMs) with the gradient direction parallel to the crack is discussed, and the differences of stress distribution between the gradient materials and the homogeneous materials are analyzed. It is shown that a mode I crack problem of FGMs with the gradient direction parallel to the crack direction can become a mixed‐mode crack problem. In FGMs, the crack initiation angles are determined by the fracture toughness gradient, elastic modulus and crack mode. If the gradient coefficients are small, the crack initiation angles in FGMs are the same as those in homogeneous materials. If the elastic modulus gradient is large, the principal stress terms without the gradient coefficients can be ignored in obtaining the crack initiation angle. In this study, all the above results are generalized to the mixed‐mode crack problems with arbitrary angle between the gradient direction and the crack direction.
Factors associated with quality of life of Brazilian older adults
Authors: Paskulin L. , Vianna L. , Molzahn A.E.
Published: February 2009

Objective:  The objective of the study was to explore factors associated with quality of life (QoL) of Brazilian community‐dwelling older adults.

Methods:  This was a descriptive exploratory cross‐sectional study. Data were collected through a household survey. A random sample of 288 older adults from Porto Alegre, Brazil participated in the study. A demographic and health data sheet, the OARS activities of daily living (ADL) scale and the WHOQOL‐BREF were administered.

Results and Discussion:  The mean age of participants was 71.2 years (SD = 7.5) and 67.4% were female. Using multiple linear regression analysis, with overall QoL as the dependent variable, perceived health status, education level, engagement in physical activity, medical conditions, age group and use of primary health care were significant associated factors. With physical QoL as the dependent variable, significant factors included: perceived health status, medical conditions, education, physical activities and dependence in ADL; with social QoL as the dependent variable, only age group and paid work were significant. In relation to environmental QoL, education and perceived health were significant factors.

Conclusions:  The results illustrate the complexity of factors influencing QoL. With a better understanding of these factors, it is possible to plan appropriate health interventions.
International perspectives on workplace bullying among nurses: a review
Authors: Johnson S.L.
Published: February 2009

Purpose:  This article examines the nursing literature on workplace bullying with the aim of reaching a better understanding of the phenomenon.

Background:  Workplace bullying occurs in many occupations and workplaces, including nursing.

Methods:  The following databases were used for the literature review: CINAHL, PubMed, Pro Quest and EBSCO host. Only articles in English were used. Articles from outside the nursing literature were also examined to gain a broader understanding of workplace bullying.

Findings:  Workplace bullying is more than a simple conflict between two individuals. It is a complex phenomenon that can only be understood through an examination of social, individual and organizational factors. Workplace bullying has been shown to impact the physical and psychological health of victims, as well as their performance at work. Workplace bullying impacts the organization through decreased productivity, increased sick time and employee attrition.

Conclusions:  More nurse‐specific research is needed in this area. Research needs to be conducted in a systematic and uniform manner so that generalizations across studies can be made. The ultimate goal of this research should be to generate an understanding of this phenomenon so that solutions can be found.
The effects of a nursing smoking cessation intervention on military students in Turkey
Authors: Ergul S. , Temel A.B.
Published: February 2009

Aim:  This study aimed to evaluate the effect of a nursing smoking cessation intervention based on the Transtheoretical Model of change on a sample of military students.

Methods:  The quasi‐experimental and longitudinal designs were used with a sample of 36 smokers from a Turkish air force school of higher education system. Data were collected through face‐to‐face interviews conducted in 1 December 2004–30 June 2005 at pre‐intervention and at each follow‐up.

Results:  At the end of the programme, the mean scores related to the perceived ‘cons’ of smoking increased significantly (P < 0.05). The students' self‐efficacy mean scores increased significantly (P < 0.01). The students' stages of change before and after the programme were significant (P < 0.01). The mean number of cigarettes smoked per day before the programme was 14.8 (SD = 5.9) and after the programme was 9.6 (SD = 6.4) at the 6‐month follow‐up (P < 0.05). The quit rate was 8.3% at the 6‐month follow‐up.

Conclusions:  The interventions by the nurses in the smoking cessation programme were effective, resulting in a positive change in attitude and behaviour that would support the students' smoking cessation and the process of cessation.
Projecting global marine biodiversity impacts under climate change scenarios
Authors: Cheung William W.L. , Lam Vicky W.Y. , Sarmiento Jorge L. , Kearney Kelly , Watson Reg , Pauly Daniel
Published: February 2009

Climate change can impact the pattern of marine biodiversity through changes in species’ distributions. However, global studies on climate change impacts on ocean biodiversity have not been performed so far. Our paper aims to investigate the global patterns of such impacts by projecting the distributional ranges of a sample of 1066 exploited marine fish and invertebrates for 2050 using a newly developed dynamic bioclimate envelope model. Our projections show that climate change may lead to numerous local extinction in the sub‐polar regions, the tropics and semi‐enclosed seas. Simultaneously, species invasion is projected to be most intense in the Arctic and the Southern Ocean. Together, they result in dramatic species turnovers of over 60% of the present biodiversity, implying ecological disturbances that potentially disrupt ecosystem services. Our projections can be viewed as a set of hypothesis for future analytical and empirical studies.
Bounded Ethicality
Authors: Kern Mary C. , Chugh Dolly
Published: February 2009

Ethical decision making is vulnerable to the forces of automaticity. People behave differently in the face of a potential loss versus a potential gain, even when the two situations are transparently identical. Across three experiments, decision makers engaged in more unethical behavior if a decision was presented in a loss frame than if the decision was presented in a gain frame. In Experiment 1 , participants in the loss-frame condition were more likely to favor gathering “insider information” than were participants in the gain-frame condition. In Experiment 2 , negotiators in the loss-frame condition lied more than negotiators in the gain-frame condition. In Experiment 3 , the tendency to be less ethical in the loss-frame condition occurred under time pressure and was eliminated through the removal of time pressure.
Software innovativeness. A comparison between proprietary and Free/Open Source solutions offered by Italian SMEs
Authors: Lamastra Cristina Rossi
Published: February 2009

Innovation processes taking place in the software sector are already widely debated. The widespread success of Free/Open Source Software (FOSS) raises new research issues, dealing with whether and how the free circulation of ideas championed by the movement and its collective management of intellectual property rights fosters innovation. The aim of this paper is to contribute to the literature by addressing the following research questions: are programs based on FOSS solutions more innovative than proprietary ones, and, if so, which innovation dimensions are typical of the FOSS production mode? Based on a sample of 134 software solutions produced by Italian Small and Medium Enterprises and using a methodology frequently applied in technology management to evaluate innovativeness of products and services, this exploratory study provides initial insights into what happens when alternative metrics are used to observe complex innovation processes in the software market.
The AMQ: A Four‐Factor Inventory of Absentmindedness and Memory
Authors: FERNAEUS SVEN‐ERIK , ÖSTBERG PER
Published: February 2009

The Absentmindedness and Memory Questionnaire (AMQ) is a new self‐rating scale designed to evaluate everyday memory problems related to absentmindedness. It includes 24 items and is based on studies of different samples (N= 623). Its test‐retest reliability is high and it has consistently shown similar factor structure. The AMQ thus measures four weakly correlated factors: Absentmindedness, Persons, Locations and Codes/Addresses. Factor analysis further indicates that Absentmindedness may include two subfactors: momentary attention deficit and prospective forgetfulness or impaired agenda memory. Gender differences were found in Persons (Female+) and Locations (Male+) but not in Absentmindedness or Codes/Addresses. The current version of AMQ has seven interindividually comparable response alternatives for each item in the questionnaire. This makes it useful as a measure of subjective absentmindedness or forgetfulness as well as a complementary measure of subjective memory for persons, locations, and codes/addresses/stories, especially at follow‐up examinations.
Intelligibility and perceptions of English proficiency
Authors: ROOY SUSAN COETZEE‐VAN
Published: February 2009

ABSTRACT:  More and more learners of English from the Expanding Circle are travelling to Outer Circle contexts to learn English or to improve their English proficiency. This is also the case for some Korean families who moved to Potchefstroom, South Africa. This phenomenon poses challenges in terms of assessment of English proficiency, and emphasizes the increasing ‘global’ reach of English observed by many researchers. A result of this phenomenon is the potential increase in communication difficulties when ‘world citizens’ use English as language of communication. This project aims at exploring these potential communication difficulties. Speech data from Korean speakers of English who live in Potchefstroom, South Africa is used to determine the levels of intelligibility, comprehension and interpretability of Korean English to South African users of English. The speech data is also used to elicit responses from the South African users of English about the perceived levels of English proficiency of the Korean participants. These perceptions are compared with a self‐evaluation of English proficiency by the Korean participants. Ultimately, the project endeavours to contribute to a better understanding of perceptions of English proficiency that could lead to solving some of the potential communication difficulties (e.g. intelligibility) in ‘world Englishes’ contexts.
Language attitudes and linguistic features in the ‘China English’ debate1
Authors: HE DEYUAN , LI DAVID C. S.
Published: February 2009

ABSTRACT:  In this paper we shall first try to define the term ‘China English’ (with our own definition of this term deliberated in the ‘Discussion’ section) as a performance variety in the larger conceptualization of World Englishes. Following that, we will adduce some linguistic features of ‘China English’ from the relevant literature at four levels (phonology, lexis, syntax, and discourse pragmatics) and discuss the arguments in favor of developing localized pedagogic models in Expanding Circle countries such as China. Then we will report on the findings of our research project: college teachers’ and students’ perceptions of the ideal pedagogic model of college English in mainland China –‘China English’ as opposed to a native‐speaker‐based standard. Our findings suggest that the preferred teaching model of college English in mainland Chinese classrooms is a standard variety of English (e.g. ‘General American’ or ‘Received Pronunciation’) supplemented with salient, well‐codified, and properly implemented features of ‘China English’. The research design and overall findings will be discussed in light of a systematic comparison and contrast with those in a similar survey conducted with mainland Chinese university students.
Ethnicity a risk factor? The relation between ethnicity and large‐ and small‐vessel disease in White people, Black people, and Asians within a hospital‐based population
Authors: Wolma J. , Nederkoorn P. J. , Goossens A. , Vergouwen M. D. I. , Van Schaik I. N. , Vermeulen M.
Published: February 2009

Background:  Previous studies suggest that in patients with ischaemic stroke, White people often present with large‐vessel and Black people with small‐vessel strokes. This study investigates the relation between large‐ and small‐vessel disease, and ethnicity in White, Black, and Asian patients in Amsterdam, the Netherlands.

Methods:  In a hospital‐based population of 668 patients ethnicity was determined by self‐identification. The relation between ethnicity and carotid stenosis, as an indicator of large‐vessel disease, was determined using univariate analysis, and adjusted for age, gender, hypertension and smoking. Subsequently the relation between ethnicity and lacunar infarcts, as a manifestation of small‐vessel disease, was investigated.

Results:  The odds ratio for having carotid stenosis, compared to White patients, was 0.55 (0.23–1.33) for Blacks, 0.53 (0.18–1.52) for Asians, and 0.64 (0.14–2.85) for other ethnicities. The adjusted odds ratio for a non‐White patient compared to a White patient was 0.44 (0.19–1.02) (P = 0.05). The non‐White patients more often presented with lacunar infarcts compared to Whites.

Conclusion:  We found an association between White patients and the presence of carotid artery stenosis. Not only in Black but also in Asian patients the association with carotid artery stenosis was substantially lower. In the non‐White population there was an association with lacunar infarcts compared to Whites.
Migrant Remittances and Household Wellbeing in Urban Zimbabwe
Authors: Bracking Sarah , Sachikonye Lloyd
Published: February 2009

Evidence from household surveying in December 2005 in Harare and Bulawayo, Zimbabwe, indicates that a wide network of international migrant remitters are ameliorating the economic crisis in Zimbabwe by sending monetary and in‐kind transfers to over 50 per cent of urban households. The research combines quantitative measurement of scale and scope, with demographic and qualitative narrative to build a holistic picture of the typography of receiving and non‐receiving households. A complex set of interrelated variables helps to explain why some households do and others do not receive income and goods from people who are away, and the economic and social extent of their subsequent benefit from them. Moreover, the mixed methods approach is designed to capture inter‐household and likely macroeconomic effects of how households receive their goods and money; and of how they subsequently exchange (if applicable), store and spend it. Evidence emerges of a largely informal, international social welfare system, but one which is not without adverse inter‐household effects for some. These include suffering exclusion from markets suffering from inflationary pressures, not least as a result of other people’s remittances. This paper explores the role of remittances, within this internationalised informal welfare system which we can map from our household survey, in reframing vulnerability and marginalization differentially among and between our subject households.
Learning to ‘talk the talk’: the relationship of psychopathic traits to deficits in empathy across childhood
Authors: Dadds Mark R. , Hawes David J. , Frost Aaron D.J. , Vassallo Shane , Bunn Paul , Hunter Kirsten , Merz Sabine
Published: February 2009

Background:  Psychopathy is characterised by profound deficits in the human tendency to feel and care about what other people feel, often known as ‘affective empathy’. On the other hand, the psychopath often has intact ‘cognitive’ empathy skills, that is, he is able to describe what and why other people feel, even if he does not share or care about those feelings. Despite a rapidly advancing neuroscience of empathy, little is known about the developmental underpinnings of this psychopathic disconnect between affective and cognitive empathy.

Methods:  The parents of N = 2760, 3–13‐year‐olds reported on the levels of empathy, callous‐unemotional traits (CU), and antisocial behaviour (AB). Consistent with current theory and measurement practice, an index of ‘psychopathic traits’ was derived from the CU and AB measures.

Results:  There are important gender and developmental differences in empathy deficits related to psychopathic traits. As expected, psychopathy is associated with severe deficits in affective empathy across all ages for males; however, no such deficits were found for females. Contrary to adult findings, psychopathic traits are associated with deficits in cognitive empathy in childhood for both sexes; however, males with high psychopathic traits appear to overcome these deficits in cognitive empathy as they move through the pubertal years.

Conclusions:  In contrast to cognitive empathy, low affective empathy does not appear to be associated with psychopathic traits in females. The characteristic disconnect between cognitive and affective empathy seen in adult male psychopathy crystallises in the pubertal years when they appear to learn to ‘talk the talk’ about other people’s emotions, despite suffering severe deficits in their emotional connection (affective empathy) to others.
Effects of nitric oxide on neutrophil influx depends on the tissue: role of leukotriene B4 and adhesion molecules
Authors: Leite ACRM , Cunha FQ , Dal‐Secco D , Fukada SY , Girão VCC , Rocha FAC
Published: February 2009

Background and purpose:  We investigated the effect of nitric oxide synthase (NOS) inhibition on polymorphonuclear cell (PMN) influx in zymosan or lipopolysaccharide (LPS)‐induced arthritis and peritonitis.

Experimental approach:  Wistar rats received intra‐articular (i.art.) zymosan (30–1000 µg) or LPS (1–10 µg). Swiss C57/Bl6 mice genetically deficient in intercellular adhesion molecule‐1 (ICAM‐1−/−) or in β2‐integrin (β2‐integrin−/−) received zymosan either i.art. or i.p. PMN counts, leukotriene B4 (LTB4), tumour necrosis factor‐α (TNF‐α) and interleukin‐10 (IL‐10) levels were measured in joint and peritoneal exudates. Groups received the NOS inhibitors NG‐nitro‐L‐arginine methyl ester (LN), nitro‐L‐arginine, N‐[3‐(aminomemethyl)benzyl] acetamide or aminoguanidine, prior to zymosan or LPS, given i.p. or s.c. in the arthritis and peritonitis experiments respectively. A group of rats received LN locally (i.art. or i.p.), 30 min prior to 1 mg zymosan i.art.

Key results:  Systemic or local NOS inhibition significantly prevented PMN migration in arthritis while increasing it in peritonitis, regardless of stimuli, concentration of NOS inhibitors and species. NOS inhibition did not alter TNF‐α and IL‐10 but decreased LTB4 in zymosan‐induced arthritis. LN administration significantly inhibited PMN influx into the joints of ICAM‐1−/− and β2‐integrin−/− mice with zymosan‐arthritis, while not altering PMN influx into the peritoneum of mice with zymosan‐peritonitis.

Conclusions and implications:  Nitric oxide has a dual modulatory role on PMN influx into joint and peritoneal cavities that is stimulus‐ and species‐independent. Differences in local release of LTB4 and in expression of ICAM‐1 and β2‐integrin account for this dual role of NO on PMN migration.
Canine cutaneous epitheliotropic T‐cell lymphoma: a review
Authors: Fontaine J. , Bovens C. , Bettenay S. , Mueller R. S.
Published: February 2009

Cutaneous epitheliotropic T‐cell lymphoma in the dog is a rare neoplastic condition with unknown aetiology. The dermatitis is characterized by infiltration of neoplastic T lymphocytes with a specific tropism for the epidermis and the adnexal structures. The different clinical and histological forms (mycosis fungoides, pagetoid reticulosis and Sézary syndrome) are reviewed. The disease in the dog resembles the human syndrome, but in 80% of the canine cases, neoplastic cells are CD4−/CD8+versus CD4+/CD8−in 90% of the human patients. Prognosis is poor with a survival time from few months to 2 years. Treatments frequently have a low efficacy. New protocols using lomustine may improve the poor prognosis of the disease.
Formation of submarginal and proglacial end moraines: implications of ice‐flow mechanism during the 1963–64 surge of Brúarjökull, Iceland
Authors: BENEDIKTSSON ÍVAR ÖRN , INGÓLFSSON ÓLAFUR , SCHOMACKER ANDERS , KJÆR KURT H.
Published: February 2009

The morphology, sedimentology and architecture of an end moraine formed by a ∼9 km surge of Brúarjökull in 1963–64 are described and related to ice‐marginal conditions at surge termination. Field observations and accurate mapping using digital elevation models and high‐resolution aerial photographs recorded at surge termination and after the surge show that commonly the surge end moraine was positioned underneath the glacier snout by the termination of the surge. Ground‐penetrating radar profiles and sedimentological data reveal 4–5 m thick deformed sediments consisting of a top layer of till overlying gravel and fine‐grained sediments, and structural geological investigations show that the end moraine is dominated by thrust sheets. A sequential model explaining the formation of submarginal end moraines is proposed. The hydraulic conductivity of the bed had a major influence on the subglacial drainage efficiency and associated porewater pressure at the end of the surge, thereby affecting the rates of subglacial deformation. High porewater pressure in the till decreased its shear strength and raised its strain rate, while low porewater pressure in the underlying gravel had the opposite effect, such that the gravel deformed more slowly than the till. The principal velocity component was therefore located within the till, allowing the glacier to override the gravel thrust sheets that constitute the end moraine. The model suggests that the processes responsible for the formation of submarginal end moraines are different from those operating during the formation of proglacial end moraines.
HOMOTHALLIC AUXOSPORULATION IN PSEUDO‐NITZSCHIA BRASILIANA (BACILLARIOPHYTA)1
Authors: Quijano‐Scheggia Sonia , Garcés Esther , Andree K. , Fortuño Jose Manuel , Camp Jordi
Published: February 2009

Most pennate diatoms are allogamous, and various types of mating systems have been described. In Pseudo‐nitzschia, reproductive stages have been identified in some species, and it is generally accepted that the genus is mainly heterothallic. Here we report homothallic auxosporulation of Pseudo‐nitzschia brasiliana Lundholm, Hasle et G. A. Fryxell. To our knowledge, this is the first verified description of homothallic sexual reproduction in the genus. Auxospore formation was observed in all 16 subclones derived from three initial clonal cultures of P. brasiliana. Pairing was followed by production of two gametes per gametangium, which fused to give two zygotes. Each zygote (early auxospore) was initially spherical and adhered to one girdle band of the parental frustule. The two auxospores tended to expand parallel to each other and perpendicular to the parental frustule. Elongation was synchronous, slightly asynchronous, or totally asynchronous. The entire process of sexual reproduction, from gamete formation to the appearance of the initial vegetative cells, took 2–4 d. The occurrence of sex in a homothallic species seems an advantageous life strategy for this species in that any encounter between cells of the right size class is potentially sexual.
Alternative method to determine the hematocrit of red blood cell units: a potential use in the apheresis unit
Authors: Farrell Sharon B. , Shelat Suresh G. , Kim Haewon C. , Drew Christa
Published: February 2009

BACKGROUND: In automated erythrocytapheresis procedures, achieving the desired‐end hematocrit (Hct) requires that the COBE Spectra (CaridianBCT) machine be programmed with the mean Hct of the replacement red blood cell (RBC) units. To determine unit Hct, data derived from quality control (QC) Hct data were utilized. However, if a unit volume is outside the quality control (QC) volume parameters, the unit is accessed to measure its Hct. In this study, 21 percent of all RBC units need to be accessed to determine the Hct, which affects 47.5 percent of patient's erythrocytapheresis procedures. Spiking the unit compromises its integrity and hastens the expiration time of the unit. Nurses must wait until the patient arrives to check units outside QC parameters, thereby delaying the start time of procedures. Even if sampled units are kept refrigerated, they cannot be returned to the blood bank inventory once spiked. The goal of this study was to determine if accurate Hct levels from RBC units could be obtained from a unique segment.

STUDY DESIGN AND METHODS: To determine the centrifuged Hct, samples were prepared from the RBC units and compared to that of the unique segment.

RESULTS: The Hct of the unique segment exceeded that of the RBC unit by a small (1.2% in AS‐1 units, 0.92% in AS‐3 units), but statistically significant amount.

CONCLUSION: The Hct from unique RBC segments closely approximates that of the original RBC unit. Unique segments can be made that will maintain the integrity and shelf life of RBC units.
Microstructure and Creep Behavior of a Si3N4–SiC Micronanocomposite
Authors: Kašiarová Monika , Shollock Barbara , Boccaccini Aldo , Dusza Jan
Published: February 2009

The microstructure and its influence on the creep behaviour of carbon derived Si3N4‐SiC micro/nanocomposite tested in bending at temperatures from 1200° to 1400°C in air has been studied. No phase and microstructure change after creep test implied that material is stable at tested temperature range. After creep test only partial crystallization of glassy intergranular phase has been observed. Creep parameters n close to 1, apparent activation energy around 350 kJ/mol together with TEM observation indicated that the main creep mechanisms is solution precipitation controlled by interface reaction in combination with grain boundary sliding caused by the amorphous intergranular phases present in microstructure. However, the grain boundary sliding is hindered by local SiC particles interlocking neighboring Si3N4 grains.
Investigation of the Effect of Cerium Doping on the Electrical Properties and Leakage Current Behavior of Lead Zirconate Thin Films Derived by the Sol–Gel Method
Authors: Mensur Alkoy Ebru , Shiosaki Tadashi
Published: February 2009

Undoped and cerium (Ce)‐doped (1 and 5 mol%) antiferroelectric thin films were obtained by a sol–gel process. All lead zirconate, PbZrO3 (denoted as PZ), films crystallized in the perovskite phase with a full [111] pseudocubic orientation and with a uniform microstructure. X‐ray photoelectron spectroscopic investigations revealed that the oxidation state of Ce is 3+ leading to an A‐site donor doping. Ce doping causes a decrease in the dielectric constant from 200 to 155 and an increase in the forward switching fields from 275 to 296 kV/cm. However, it also leads to a significant decrease in the leakage current density and this effect is more pronounced for the 5% doping case, where an order of magnitude lower leakage current is obtained compared with the undoped PZ. Analyses of leakage current behavior indicate dominance of a space charge limited current type leakage current and also a possible contribution from a Poole–Frenkel type emission in certain temperature or field regimes.
Modifying Structures and Ferroelectric Properties of Pb(Zr0.6Ti0.4)O3 Thin Films by Constraint‐Annealing of Precrystallized Film
Authors: Hsu Fan‐Yi , Leu Ching‐Chich , Lu Yen‐Liang , Ho Shu‐Te , Hu Chen‐Ti
Published: February 2009

A tensile or compressive mechanical constraint was applied, during annealing, on the Pb(Zr0.6Ti0.4)O3 (PZT) ferroelectric films to investigate the effects of stress on its crystal structure and electric properties. The external stress was applied by bending the substrate into a circular section. By using both precrystallized film structure and high constraint strain (0.08%), the stress states of PZT during the crystallization process became controllable. Structural change of polycrystalline PZT was observed when crystallized under a compression constraint. Moreover, these films with compression constraint annealing exhibited enhanced remnant polarization by ∼70% and increased dielectric constant by ∼68%. The variations in ferroelectric behaviors were correlated to domain configuration, texture, amount of pyrochlore phase, grain size and residual stress, which are dependent on the stress state during annealing process.
Structure Characterization and Tuning of Perovskite‐Like NaTaO3 for Applications in Photoluminescence and Photocatalysis
Authors: Hu Che‐Chia , Tsai Chien‐Cheng , Teng Hsisheng
Published: February 2009

Perovskite‐like NaTaO3 powders have potential applications in photoluminescence and photocatalysis. Sol–gel, hydrothermal and solid‐state methods were used to synthesize NaTaO3 powders of different crystalline structures, which were identified by Rietveld refinement simulation of X‐ray diffraction patterns and transmission electron microscopic diffraction. The refinement results show that the sol–gel specimen has a monoclinic phase with a Ta−O−Ta bond angle of 179° while the hydrothermal and solid‐state specimens have an orthorhombic phase with bond angles of 163° and 157°, respectively. By excitation with a 304 nm light source, these NaTaO3 specimens show photoluminescence emission at ca. 450 nm. The photoluminescence intensity of the specimens had an order solid state >hydrothermal >sol–gel, which is opposite to that of the Ta−O−Ta bond angle. On the other hand, the photocatalytic activity of the NaTaO3 specimens in water splitting showed the same order as that of the Ta−O−Ta bond angle. This paper directly evidenced that the Ta−O−Ta bond angle affects the separation rate of the photo‐induced charges, as well as that structure tuning of tantalates is achievable and crucial for applications in photoluminescence and photocatalysis.
Ion‐Specific Interaction of Alumina Surfaces
Authors: Yilmaz Huseyin , Sato Kimiyasu , Watari Koji
Published: February 2009

There has been a long‐standing question about the effect of the type of ionic species on the surface forces that is not considered in the classical Derjaguin–Landau–Vervey–Overbeek theory. Originating from the work of Hofmeister, the ion‐specific interaction between particles has been known for a long time. Depending on the pH and oxide type, a direct or a reverse Hofmeister effect has been observed in colloidal suspensions at high salt concentrations. The origin of this effect is not well understood but is qualitatively taken into account in colloid science. From macroscopic behavior, it is predicted that alumina particles in LiCl solution attract each other more strongly than in CsCl solutions. If such an effect does exist, then force curves obtained using the colloid probe technique may detect the difference. Using chloride salts of the two end members of the Hofmeister series, namely Li+ and Cs+, stronger attraction in the LiCl electrolyte solution compared with the CsCl one was measured for the first time at the microlevel between alumina surfaces at pH=11.
Flexible Dielectric Bi1.5Zn1.0Nb1.5O7 Thin Films on a Cu‐Polyimide Foil
Authors: Ryu Jungho , Kim Kun‐Young , Choi Jong‐Jin , Hahn Byung‐Dong , Yoon Woon‐Ha , Lee Byoung‐Kuk , Park Dong‐Soo , Jeong Dae‐Yong , Park Chan
Published: February 2009

Flexible thin films of Bi1.5Zn1.0Nb1.5O7 (BZN) were deposited on a Cu/polyimide (PI) foil by aerosol deposition at room temperature. The BZN film thickness was in the range of 1.2–17.9 μm. Highly dense and nanocrystalline films were obtained without any heat treatment. The dielectric constant and loss of the film at 100 kHz were over 150 and 0.04, respectively. Furthermore, the as‐deposited film showed markedly low leakage current densities of <10−9 A/cm2 at 3.0 V. These reasonably high dielectric properties were due to the nanocrystallinity of the films. The results confirm the significant potential of the BZN films as passive components in flexible printed circuit board applications.
Crystal Structure and Electronic Structure of a Novel Hf3AlN Ceramic
Authors: Li Fangzhi , Hu Chunfeng , Wang Jiemin , Liu Bin , Wang Jingyang , Zhou Yanchun
Published: February 2009

In this work, we have fabricated a novel ternary aluminum nitride, Hf3AlN, via a reactive hot pressing method using hafnium and aluminum nitride as starting materials. The crystal structure of Hf3AlN was established by a combination ofab initiocalculation, X‐ray diffraction, and electron diffraction analyses. The point group and space group of Hf3AlN were determined asmmmandCmcm, respectively. The lattice constants area=0.3298 nm,b=1.135 nm,c=0.8842 nm and the atomic positions are Hf1 at 4c(0, 0.0441, 0.2500), Hf2 at 8f(0, 0.3701, 0.0437), Al at 4c(0, 0.7469, 0.2500), and N at 4a(0, 0, 0). Electronic structure analysis demonstrated that Hf3AlN should possess metallic conductivity and intrinsic damage tolerance. We hope that this work will inspire future experimental research on this Hf‐based ternary ceramic.
Synthesis, Processing, Mechanical, and Biological Property Characterization of Hydroxyapatite Whisker‐Reinforced Hydroxyapatite Composites
Authors: Bose Susmita , Banerjee Ashis , Dasgupta Sudip , Bandyopadhyay Amit
Published: February 2009

Effects of hydroxyapatite (HA) whiskers addition on densification, mechanical, and biological properties of HA compacts were studied for their use as an implant material for orthopedic and dental applications. HA nanopowder was synthesized using reverse micelle as template system, and urea hydrolysis synthesis route was used to prepare micrometer‐sized HA whiskers. Poly (oxyethylene)12 nonylphenol ether (NP12) and cyclohexane were used as surfactant and organic solvent, respectively, for the reverse micelle microemulsion system. Desired microstructure in sintered HA composite was obtained by mixing Mg2+ as a dopant in HA nanopowders, and Al3+ as a dopant in HA whiskers. Compacts were processed using pressureless sintering. With an increase in whisker content from 0 to 10 wt%, the average compressive strength of HA compacts decreased from 120 to 90 MPa. HA composite processed with 10 wt% HA whisker showed a microhardness of 3.6 GPa and an average indentation fracture toughness of 1.5 MPa·m1/2. Mineralization study in simulated body fluid showed deposition of octacalcium phosphate on sintered HA compacts. In vitro cytotoxicity tests with human osteoprecursor cell line confirmed excellent osteoblast cell attachment and growth on the sintered HA compacts with 0, 10, and 20 wt% HA whiskers.
Gelcasting of Magnesium Aluminate Spinel Powder
Authors: Ganesh Ibram , Olhero Susana M. , Torres Paula M. C. , Ferreira José M. F.
Published: February 2009

A stoichiometric MgAl2O4spinel (MAS) powder was processed in aqueous media and consolidated by gelcasting from suspensions containing 41–45 vol% solids loading. The MAS powder was first obtained by heat treating a compacted mixture of α‐Al2O3and calcined caustic MgO at 1400°C for 1 h, followed by crushing and milling. Then, its surface was passivated against hydrolysis using an ethanol solution of H3PO4and Al(H2PO4)3. The as‐treated surface MAS powder could then be dispersed in water using tetra methyl ammonium hydroxide and an ammonium salt of poly‐acrylic acid (Duramax D‐3005) as dispersing agents. The as‐obtained stable suspensions were gelcast, dried, and sintered at 1650°C for 1–3 h. For comparison purposes, the treated powder was also compacted by die pressing of freeze‐dried granules and sintered along with gelcast samples. Near‐net‐shape MAS components with 99.55% of the theoretical density could be fabricated by aqueous gelcasting upon sintering at 1650°C for 3 h. The MAS ceramics fabricated by gelcasting and die pressing exhibited comparable properties.
Preparation, Characterization, and Photocatalytic Properties of CaNb2O6 Nanoparticles
Authors: Cho In‐Sun , Bae Shin Tae , Yim Dong Kyun , Kim Dong Wan , Hong Kug Sun
Published: February 2009

CaNb2O6 nanoparticles with a size range of 30–50 nm were synthesized by heat treatment at 600°C after a solvothermal process and their optical and photocatalytic properties were investigated. The prepared powders were characterized by X‐ray powder diffractometer, field‐emission scanning electron microscope, transmission electron microscope, UV‐Vis diffuse reflectance spectroscopy, Fluorescence spectroscopy, and Raman spectroscopy. Compared with a powder of the same material prepared by a solid‐state reaction (SS) method, the nanoparticles exhibited a higher Brunauer–Emmett–Teller (BET) surface area, more efficient light absorption, and enhanced photocatalytic activity for producing H2 from pure water under UV irradiation. The photoluminescence spectra revealed that a radiative recombination process is dominant in the powder prepared by the SS method (strong blue emission at 300 K) under UV light irradiation, while no obvious emission was observed in the nanoparticles. This decrease of the radiative recombination as well as the higher optical absorption ability and higher BET surface area resulting from the reduced dimensionality led to enhanced photocatalytic activity of the nanoparticles.
Perspectives on Race and Incarceration, Part II
Authors: Jones Joseph
Published: February 2009

“From Incarceration Epidemic to a Prison‐Community Cultural Continuum,” by Tony L Whitehead
Quantification of personal solar UV exposure of outdoor workers, indoor workers and adolescents at two locations in Southeast Queensland
Authors: Kimlin M. G. , Parisi A. V. , Wong J. C. F.
Published: February 2009

Quantification of human exposure to solar ultraviolet (UV) radiation at two locations was performed to study the effect of occupation (outdoor workers, schoolchildren and home workers) and location on personal UV exposure. The study took place on 13 and 14 February 1997 in Toowoomba (27.5°S, 151.9°E) and Brisbane (27.4°S, 153.1°E) in Southeast Queensland, Australia. From the data collected by calibrated ambient UV monitoring stations located in Toowoomba and Brisbane, Toowoomba received 16% more UVB (280–320 nm) than Brisbane from 07:00 to 17:00 Australian Eastern Standard Time (EST) on the 13 February, 1997 and 10% more UVB on the 14 February 1997. All groups, regardless of occupation, in this study received a median erythemal UV exposure of over 2 MED on the shoulder over the 2 day period. The highest median erythemal UV exposure to the shoulder over the 2 day period was 6 MED in Toowoomba outdoor workers. The median 2 day erythemal exposure to the shoulder was 33% higher in Toowoomba than in Brisbane for the outdoor workers, 50% higher in Toowoomba compared to Brisbane for the schoolchildren and 25% higher in Toowoomba than Brisbane for the home workers.
Quantitative evaluation of the personal erythemal ultraviolet exposure in a car
Authors: Parisi A. V. , Wong J. C. F.
Published: February 2009

Erythemal ultraviolet (UV)‐radiation exposure to the right hand, midarm, shoulder, chin, nose and left and right sides of the face has been evaluated in a car from a large family class and a car from a small car class. In the small car, the site with highest exposure received 2.2 times more radiation than the site with the highest exposure in the larger car. In both cars, highest erythemal exposures were to the right shoulder, arm, and hand. Over a 6 h period, erythemal exposure to the right shoulder of a person in the driver's seat of the small car was 3.1 mJ.cm‐2.
Update on enzyme and molecular defects in porphyria
Authors: Elder G. H.
Published: February 2009

Each porphyria results from decreased activity of one of the enzymes of haem biosynthesis. The molecular basis of enzyme deficiencies in acute intermittent porphyria (AIP), variegate porphyria (VP) and congenital erythropoietic porphyria (CEP) is outlined. All three conditions show extensive allelic heterogeneity. In the autosomal dominant disorders, AIP and VP, no genotype/phenotype correlations have been demonstrated, and the explanation for their low clinical penetrance remains uncertain. In AIP and VP, mutational analysis is superior to biochemical methods for screening families for latent porphyria. In the autosomal recessive condition, CEP, there is some genotype/phenotype correlation — one common mutation (C73R) being associated with severe disease in homozygotes. Porphyria cutanea tarda (PCT) is not a simple monogenic disorder. Patients appear to have an inherited susceptibility to inactivation of hepatic uroporphyrinogen decarboxylase (UROD) as part of a response to hepatocyte injury by alcohol, HCV and other agents. Inherited factors that, in combination, may predispose to PCT include mutations in the UROD gene, present in about 20% of patients, and the C282Y mutation in the haemochromatosis (HFE) gene.