bluuebunny/crossref_metadata_2025 huggingface dataset:
Habitat expansion of an exotic lace bug, Corythucha marmorata (Uhler) (Hemiptera: Tingidae), on the Kii Peninsula and Shikoku Island in western Japan
Authors: KATO Atsushi , OHBAYASHI Nobuo
Published: June 2009

Habitat expansion of an exotic lace bug Corythucha marmorata (Uhler) was observed on the Kii Peninsula in 2003–2004, and on Shikoku Island between 2004 and 2007. The bug was first sighted in Nishinomiya City in Hyogo Prefecture in 2000, and then further south in central Kii Peninsula in 2003 before reaching the southern tip of the peninsula by 2004. The bug was first observed in the Tokushima and Ehime Prefectures of Shikoku Island in 2004, after which the range expanded and extended across the entire island by 2007. In this study, six wild Asteraceae species were identified as the host plants to the lace bug.
Putting Density Back into the Habitat‐Quality Equation: Case Study of an Open‐Nesting Forest Bird
Authors: PÉROT AURORE , VILLARD MARC‐ANDRÉ
Published: June 2009

Abstract: Ecological traps and other cases of apparently maladaptive habitat selection cast doubt on the relevance of density as an indicator of habitat quality. Nevertheless, the prevalence of these phenomena remains poorly known, and density may still reflect habitat quality in most systems. We examined the relationship between density and two other parameters of habitat quality in an open‐nesting passerine species: the Ovenbird (Seiurus aurocapilla). We hypothesized that the average individual bird makes a good decision when selecting its breeding territory and that territory spacing reflects site productivity or predation risk. Therefore, we predicted that density would be positively correlated with productivity (number of young fledged per unit area). Because individual performance is sensitive to events partly determined by chance, such as nest predation, we further predicted density would be weakly correlated or uncorrelated with the proportion of territories fledging young. We collected data in 23 study sites (25 ha each), 16 of which were located in untreated mature northern hardwood forest and seven in stands partially harvested (treated) 1–7 years prior to the survey. Density explained most of the variability in productivity (R2= 0.73), and there was no apparent decoupling between density and productivity in treated plots. In contrast, there was no significant relationship between density and the proportion of territories fledging ≥1 young over the entire breeding season. These results suggest that density reflects habitat quality at the plot scale in this study system. To our knowledge this is one of the few studies testing the value of territory density as an indicator of habitat quality in an open‐nesting bird species on the basis of a relatively large number of sizeable study plots.
Management Decentralization and Montane Forest Conditions in Tanzania
Authors: PERSHA LAUREN , BLOMLEY TOM
Published: June 2009

Abstract:  We examined how differences in local forest‐management institutions relate to disparate anthropogenic forest disturbance and forest conditions among three neighboring montane forests in Tanzania under centralized, comanaged, or communal management. Institutional differences have been shaped by decentralization reforms. We conducted semistructured interviews with members of forest management committees, local government, and village households and measured anthropogenic disturbance, tree structure, and species composition in forest plots. We assessed differences in governance system components of local institutions, including land tenure, decision‐making autonomy by forest users, and official and de facto processes of rule formation, monitoring, and enforcement among the three management strategies. We also assessed differences in frequencies of prohibited logging and subsistence pole cutting, and measures of forest condition. An adjacent research forest served as an ecological reference for comparison of forest conditions. Governance was similar for comanaged and centralized management, whereas communal managers had greater tenure security and decision‐making autonomy over the use and management of their forest. There was significantly less illegal logging in the communal forest, but subsistence pole cutting was common across all management strategies. The comanaged forest was most disturbed by recent logging and pole cutting, as were peripheral areas of the larger centralized forest. This manifested in more degraded indicators of forest conditions (lower mean tree size, basal area, density of trees ≥ 90 cm dbh, and aboveground biomass and higher overall stem density). Greater tenure security and institutional autonomy of the communal strategy contributed to more effective management, less illegal logging, and maintenance of good forest conditions, but generating livelihood benefits was a challenge for both decentralized strategies. Our results underscore the importance of well‐designed institutional arrangements in forest management and illustrate mechanisms for improved forest governance and conservation in the context of Tanzanian decentralization reforms.
Unintentional Fall Injuries Associated with Walkers and Canes in Older Adults Treated in U.S. Emergency Departments
Authors: Stevens Judy A. , Thomas Karen , Teh Leesia , Greenspan Arlene I.
Published: June 2009

OBJECTIVES: To characterize nonfatal, unintentional, fall‐related injuries associated with walkers and canes in older adults.

DESIGN: Surveillance data of injuries treated in hospital emergency departments (EDs), January 1, 2001, to December 31, 2006.

SETTING: The National Electronic Injury Surveillance System All Injury Program, which collects data from a nationally representative stratified probability sample of 66 U.S. hospital EDs.

PARTICIPANTS: People aged 65 and older treated in EDs for 3,932 nonfatal unintentional fall injuries and whose records indicated that a cane or a walker was involved in the fall.

MEASUREMENTS: Sex, age, whether the fall involved a cane or walker, primary diagnosis, part of the body injured, disposition, and location and circumstances of the fall.

RESULTS: An estimated 47,312 older adult fall injuries associated with walking aids were treated annually in U.S. EDs: 87.3% with walkers, 12.3% with canes, and 0.4% with both. Walkers were associated with seven times as many injuries as canes. Women's injury rates exceeded those for men (rate ratios=2.6 for walkers, 1.4 for canes.) The most prevalent injuries were fractures and contusions or abrasions. Approximately one‐third of subjects were hospitalized for their injuries.

CONCLUSION: Injuries and hospital admissions for falls associated with walking aids were frequent in this highly vulnerable population. The results suggest that more research is needed to improve the design of walking aids. More information also is needed about the circumstances preceding falls, both to better understand the contributing fall risk factors and to develop specific and effective fall prevention strategies.
Maintenance of in vitro properties of leukoreduced whole blood–derived pooled platelets after a 24‐hour interruption of agitation
Authors: Vassallo Ralph R. , Wagner Stephen J. , Einarson Mindy , Nixon Janice , Ziegler Diana , Moroff Gary
Published: June 2009

BACKGROUND: Continuous agitation during platelet concentrate (PC) storage is frequently interrupted during shipping. Studies have evaluated the effects of interrupted agitation in apheresis and single whole blood–derived PCs, but not PC pools. This study evaluated in vitro properties of pooled whole blood–derived platelets (PLTs) after a 24‐hour interruption of agitation.

STUDY DESIGN AND METHODS: Eleven ABO‐identical leukoreduced whole blood–derived PCs (Leukotrap RC‐PL, Pall), pooled in a transfer container, were equally divided into each of two CLX‐HP containers (Acrodose PL, Pall). One pool (test) was held in a shipping container unagitated for 24 hours between Day 2 and Day 3, while the other (control) was continuously agitated.

RESULTS: Ten pairs underwent in vitro assays after 5 and 7 days' storage. Pools contained a mean (±SD) of 5.0 × 1011 ± 0.4 × 1011 PLTs. Interrupting agitation for 24 hours reduced test pool pH versus control after 5 days' storage (6.77 ± 0.15 vs. 6.98 ± 0.06, p = 0.0005). Test and control pH differences were greater after 7 days' storage (6.17 ± 0.29 vs. 6.65 ± 0.14, p < 0.0001); 5 of 10 test pool pHs were less than 6.2 (vs. 0 of 10 controls). Other test pool key in vitro variables were reduced compared with controls after 5 days' storage, with greater differences after 7 days.

CONCLUSION: After 5 days' storage, pooled leukoreduced whole blood–derived‐PCs in CLX‐HP containers adequately maintained pH and other key in vitro variables after a 24‐hour interruption of agitation. After 7 days' storage, 5 of 10 pools did not maintain a pH value of 6.2 or greater while matched continuously agitated units did.
Quantitation of human herpesvirus 8 (HHV‐8) antibody in patients transfused with HHV‐8–seropositive blood
Authors: Fowlkes Ashley L. , Brown Cedric , Amin Minal M. , Roback John D. , Downing Robert , Nzaro Esau , Mermin Jonathan , Hladik Wolfgang , Dollard Sheila C.
Published: June 2009

BACKGROUND: Human herpesvirus 8 (HHV‐8) is endemic in Uganda where seroprevalence is approximately 40%. In a previous study, Ugandan patients receiving blood transfusions had multiple serum specimens collected for 6 months after transfusion to monitor for HHV‐8 infection. It was observed that several HHV‐8–seronegative patients were unexpectedly HHV‐8 seropositive after blood transfusion.

STUDY DESIGN AND METHODS: This study measured HHV‐8 antibody in serially collected serum specimens from 542 patients who received transfusions and evaluated the risk of HHV‐8 infection as a function of HHV‐8 antibody levels in the donors.

RESULTS: HHV‐8 antibody was observed in 52% of patients transfused with HHV‐8–seropositive blood in amounts that corresponded with their donor's antibody titer and waned within 40 days. Higher levels of passive HHV‐8 antibody in patients who received transfusions appeared to be associated with a lower risk of HHV‐8 infection.

CONCLUSION: The source of transient antibody in patients who received transfusions was determined to be the transfused blood. Donors with higher HHV‐8 antibody titers may have been less likely to have infectious virus in the blood.
Comparison of frozen versus desiccated reference human red blood cells for hemagglutination assays
Authors: Ho David , Schierts Jennifer , Zimmerman Zea , Gadsden Isaac , Bruttig Stephen
Published: June 2009

BACKGROUND: Red blood cells (RBCs) are commonly used fresh or stored in frozen format for identification of patients' antibodies and serologic specificity of such antibodies at reference laboratories. However, maintaining a large pool of fresh RBCs is impossible in a blood‐banking environment and blood in frozen format poses a logistic disadvantage in terms of accessibility, maintenance cost, safety, and sample recovery. This study explores an alternative, desiccation storage method for RBCs to provide a reagent that supports greater utilization and flexibility for reference laboratories.

STUDY DESIGN AND METHODS: RBCs from five donors were used in the study. RBCs were processed and kept in either frozen or desiccated format. Study variables for either the frozen or the desiccated cells included cell recovery as quantified by cell counts, gross microscopic examination, and hemagglutination assays.

RESULTS: The mean percentage of cell recovery for thawed and washed frozen RBCs was 20% versus 50% for rehydrated and washed desiccated RBCs. Microscopic examination of thawed cells from the frozen preparation showed cells with irregular shapes, a sharp contrast when compared with rehydrated cells from the desiccated preparation, where cells are mostly intact, smooth surface, and biconcave in structure. Cells in both preparations performed well in manual agglutination tests.

CONCLUSION: Desiccation preservation of RBCs provides a somewhat better RBC recovery and cell structure stability, while maintaining the necessary antigen‐antibody reactions for cell surface markers, which will allow desiccated RBCs to be archived in blood collecting and processing reference laboratories.
Pathogen reduction of fresh plasma using riboflavin and ultraviolet light: effects on plasma coagulation proteins
Authors: Hornsey Valerie S. , Drummond Olive , Morrison Alex , McMillan Loraine , MacGregor Ian R. , Prowse Chris V.
Published: June 2009

BACKGROUND: Treatment with riboflavin and ultraviolet (UV) light reduces the pathogens present in blood components. This study assessed changes to the coagulation proteins that had occurred during this treatment of fresh plasma units before freezing.

STUDY DESIGN AND METHODS: Twenty fresh plasma units (230 ± 30 mL) were treated by the Mirasol process (CaridianBCT Biotechnologies) and frozen within 8 hours of donation. Plasma units were combined with 35 mL of a 500 µmol/L riboflavin solution in an illumination bag to achieve a final concentration of approximately 60 µmol/L riboflavin. The bag was placed in the Mirasol illuminator and exposed to UV light (6.24 J/mL). Samples were frozen before and after treatment.

RESULTS: Recoveries observed were 67.7 ± 3.9% Factor (F)XI, 68.5 ± 3.3% FVIII:C, 78.8 ± 4.5% fibrinogen, 78.9 ± 4.1% FV, 79.0 ± 4.2% FVII, 79.0 ± 8.6% F IX, 79.7 ± 2.6% FX, and 85.0 ± 3.7% FII. Von Willebrand factor (VWF) antigen, VWF:ristocetin cofactor, and ADAMTS13 recoveries were 87.0 ± 7.1, 85.5 ± 6.6, and 73.3 ± 15.2%, respectively, while that of protein C was 83.6 ± 2.6%. A loss of high‐molecular‐weight VWF multimers was observed in most units. Recoveries for protein S, antithrombin, and plasmin inhibitor were greater than 90%. The mean FVIII:C concentration, after treatment, was 0.76 ± 0.17 IU/mL.

CONCLUSIONS: As with other pathogen reduction technologies, the Mirasol process resulted in some loss of coagulation factor activity. For most Mirasol‐treated units and for most of the tested factors this is unlikely to have clinical impact, but trials are required to demonstrate this.
Evaluating Critical Uncertainty Thresholds in a Spatial Model of Forest Pest Invasion Risk
Authors: Koch Frank H. , Yemshanov Denys , McKenney Daniel W. , Smith William D.
Published: June 2009

Pest risk maps can provide useful decision support in invasive species management, but most do not adequately consider the uncertainty associated with predicted risk values. This study explores how increased uncertainty in a risk model's numeric assumptions might affect the resultant risk map. We used a spatial stochastic model, integrating components for entry, establishment, and spread, to estimate the risks of invasion and their variation across a two‐dimensional landscape for Sirex noctilio, a nonnative woodwasp recently detected in the United States and Canada. Here, we present a sensitivity analysis of the mapped risk estimates to variation in key model parameters. The tested parameter values were sampled from symmetric uniform distributions defined by a series of nested bounds (±5%, … , ±40%) around the parameters' initial values. The results suggest that the maximum annual spread distance, which governs long‐distance dispersal, was by far the most sensitive parameter. At ±15% or larger variability bound increments for this parameter, there were noteworthy shifts in map risk values, but no other parameter had a major effect, even at wider bounds of variation. The methodology presented here is generic and can be used to assess the impact of uncertainties on the stability of pest risk maps as well as to identify geographic areas for which management decisions can be made confidently, regardless of uncertainty.
Epidemiologic Evidence for Chloroprene Carcinogenicity: Review of Study Quality and its Application to Risk Assessment
Authors: Bukowski John Arthur
Published: June 2009

This article evaluates the quality and weight of evidence associated with epidemiologic studies of cancer among occupational cohorts exposed to chloroprene. The focus is on liver, lung, and lymphohematopoietic cancers, which had been increased in early studies. Literature searches identified eight morbidity/mortality studies covering seven chloroprene‐exposed cohorts from six countries. These studies were summarized and their quality was assessed using the 10 criteria suggested by the U.S. Environmental Protection Agency. The limitations within this literature (primarily the early studies) included crude exposure assessment, incomplete follow‐up, uncertain baseline rates, and uncontrolled confounding by factors such as smoking, drinking, and co‐exposure to benzene and vinyl chloride. Four cohorts were studied by the same group of investigators, who reported no overall increased associations for any cancers. This four‐cohort study was by far the most rigorous, having the most comprehensive exposure assessment and follow‐up and the most detailed documentation. This study also contained the two largest cohorts, including an American cohort from Louisville, Kentucky, that ranked at or near the top for each of the 10 quality criteria. There was evidence of a strong healthy worker effect in the four‐cohort study, which could have hidden small excess risks. Small increased risks were suggested by internal or company‐specific analyses, but these were most likely caused by uncontrolled confounding and low baseline rates. Overall, the weight of evidence does not support any substantial link between chloroprene exposure and cancer, but inconsistencies and a lack of control for major confounders preclude drawing firmer conclusions.
Portents of Pluralism: How Hybrid Regimes Affect Democratic Transitions
Authors: Brownlee Jason
Published: June 2009

The original studies of “competitive authoritarianism” and “hegemonic authoritarianism” inspected the occurrence of hybrid regimes during the 1990s but stopped short of testing their propensity for democratic change. This article assesses the causal effects of hybrid regimes, and the post–cold war period itself, on regime breakdown and democratization. Using a dataset of 158 regimes from 1975 to 2004, and a discrete measure for transitions to electoral democracy, I find that competitive authoritarian regimes are not especially prone to losing power but are significantly more likely to be followed by electoral democracy: vigorous electoral contestation does not independently subvert authoritarianism, yet it bodes well for democratic prospects once incumbents are overthrown.
How Foreign Aid Can Foster Democratization in Authoritarian Regimes
Authors: Wright Joseph
Published: June 2009

Donors in recent years have made some foreign aid conditional on progress toward democracy. This study investigates whether and how such conditionality works in practice. The promise of higher aid if the country democratizes only provides an incentive for democratization for political leaders who expect to remain in office after democratization occurs. I show that dictators with large distributional coalitions, who have a good chance of winning fair elections, tend to respond to aid by democratizing. In contrast, aid helps dictators with the smallest distributional coalitions hang on to power. I present a model that shows a dictator's decision calculus, given different a priori support coalitions and varying degrees of aid conditionality, and test the model implications with data from 190 authoritarian regimes in 101 countries from 1960 to 2002.
Local Institutions and the Politics of Urban Growth
Authors: Lubell Mark , Feiock Richard C. , De La Cruz Edgar E. Ramirez
Published: June 2009

This article uses a political market framework to analyze how the structure of local political institutions affects the relative political influence of development and environmental interests in the context of urban growth. Using panel data from 406 Florida cities from 1998 to 2003, the empirical analysis finds important interaction effects between the structure of city executive branch institutions and interest group variables. The economic and political forces driving urban growth do not operate identically in all cities—they vary as a function of institutional context. Institutional structure helps determine which interest groups have their preferences reflected in local land‐use changes and development patterns. The resulting patterns suggest a “sustainability paradox” wherein richer, environmental interests push for the preservation of environmental amenities while at the same time accelerating the number of residential units built in a community.
The Dynamics of Partisan Conflict on Congressional Approval
Authors: Ramirez Mark D.
Published: June 2009

Partisan divisions in American politics have been increasing since the 1970s following a period where scholars thought parties were in decline. This polarization is observed most frequently within the debates and deliberation across issues within Congress. Given that most studies of public opinion place the behavior of elites at the center of public attitudes, surprisingly little research examines the effect of partisan conflict on the mass public. This research examines quarterly congressional approval data from 1974 to 2000 to determine the consequences, if any, of party conflict on the dynamics of congressional approval. The findings indicate that over‐time changes in partisan conflict within Congress have a direct and lasting effect on how citizens think about Congress.
Antisocial Security: The Puzzle of Beggar‐Thy‐Children Policies
Authors: Grafstein Robert
Published: June 2009

The U.S. Social Security program has irrevocably transferred substantial wealth from workers to their ostensibly altruistic parents. After some alternative explanations for this paradox are addressed, a formal model is developed to show that a majority of rational voters who care about their descendants can support the preservation of current benefits for themselves but accept the prospect of Social Security's future retrenchment. Incorporating elements ofTabellini's (2000)positive theory of Social Security andBénabou and Ok's (2001)analysis of income mobility, the model identifies specific forces affecting this time‐varying individual support for Social Security. These forces are embodied in three hypotheses related to income mobility, relative income level, and age. An ordered logit analysis of cumulative ANES data supports these hypotheses.
Systematically Dependent Competing Risks and Strategic Retirement
Authors: Fukumoto Kentaro
Published: June 2009

In many applications of survival analysis, the risk of an event occurring for one reason is dependent on the risk of the same event occurring for another reason. For example, when politicians suspect they might lose an election, they may strategically choose to retire. In such situations, the often‐used multinomial logit model suffers from bias and underestimates the degree of strategic retirement, for example, to what extent poor prior electoral performance diminishes electoral prospects. To address this problem, the present article proposes a systematically dependent competing‐risks (SDCR) model of survival analysis. Unlike the frailty model, the SDCR model can also deal with more than two risks. Monte Carlo simulation demonstrates how much the SDCR model reduces bias. Reanalysis of data on U.S. congressional careers (Box‐Steffensmeier and Jones 2004) documents the strategic retirement of representatives, indicating that electoral pressure is more effective at turning out incumbents than previously recognized.
Photonic Bandgap and Photoluminescence in TbPO4 Inverse Opal with Coexistence of the (001) and (111) Orientations
Authors: Yang Zhengwen , Huang Xueguang , Li Sun , Zhou Ji , Li Bo , Yu Cailan
Published: June 2009

Inverse opal photonic crystals of TbPO4 with coexisting (001) and (111) orientations were prepared by the self‐assembly technique in combination with a sol–gel method. Optical and photoluminescence (PL) properties of the (001) and (111) orientation regions were investigated in TbPO4 inverse opals. It was found that the photonic bandgap along the (001) orientation shifted to shorter wavelengths compared with that of the (111) orientation in the inverse opals. The effect of the photonic bandgap on the spontaneous emission of the 5D4→7Fn transitions of Tb3+ was observed in the TbPO4 inverse opals. Significant suppression of the emission was detected if the photonic bandgap overlapped with the Tb3+ ions emission band.
An Analysis of Four Different Approaches to Predict and Control Sintering
Authors: Reiterer Markus W. , Ewsuk Kevin G.
Published: June 2009

Understanding and predicting sintering, which have been goals since the first attempts to mathematically describe the sintering process in the 1950s, are necessary to eliminate machining after sintering and to reliably predict and control the sintered microstructure and the resultant mechanical and other desired properties. In this study, four different sintering models are evaluated relative to one another and the experimental data, revealing their attributes, deficiencies, and modifications/improvements in order to facilitate their application, including the following: (i) a microstructure‐based model for solid state sintering, mainly developed by Riedel and Svoboda (RS); (ii) a viscous sintering (SOVS) model developed by Skorohod and advanced by Olevsky; (iii) a Kinetic Monte Carlo (KMC) model provided by Tikare; and (iv) the master sintering curve (MSC) approach introduced by Johnson et al. For different reasons, all four models have deficiencies that preclude achieving the most challenging goal of being able to comprehensively understand and predict sintering behavior: (i) the RS and the KMC models are complicated and difficult to use; (ii) the SOVS model cannot predict microstructure evolution; and (iii) the KMC model and the MSC have no stresses in their mathematical description, so they cannot simulate the effects of external forces. Each model also has attributes: (i) the KMC model allows one to follow the evolution of mesostructure; (ii) the MSC concept and the RS model are suitable for predicting densification curves for a wide variety of temperature–time profiles; and (iii) the SOVS and the RS models, which are implemented into finite element codes, can be used to predict density gradients and the warping of complex shape parts. Individually and together, the MSC, KMC, SOVS, and RS models can be useful tools to advance the fundamental understanding and improve the control of sintering.
Pressureless Sintering of Apatite/Wollastonite–Phlogopite Glass–Ceramics
Authors: Faeghi‐Nia Aida , Marghussian Vahak K. , Taheri‐Nassaj Ehsan , Pascual Maria J. , Durán Alicia
Published: June 2009

Apatite/wollastonite (A/W)—phlogopite (Ph) glass‐ceramics of various compositions were prepared by means of pressureless sintering of two frit mixtures. Sintering conditions were studied by differential thermal analysis (DTA) and hot‐stage microscopy. The sintered samples were characterized by X‐ray diffraction. The results showed that by addition of a frit of phlogopite composition to a frit of A/W composition, the crystallization temperature decreases which results in suppressing the sintering process. The 50–50 frits mixture could be sintered to 0.90 relative density after 1 h heating at 1100°C. The type and sequence of formation of crystalline phases were also modified. Whereas the A/W glass–ceramic crystallized to apatite and wollastonite, the crystallization products of 50–50 frits mixture were fluoro‐apatite, wollastonite, diopside, and mellilite.
Effect of Synthesis Atmosphere on the Microwave Dielectric Properties of ZnO Powders
Authors: Huang Yunxia , Cao Quanxi , Li Zhimin , Jiang Haiqing , Wang Yupeng , Li Guifang
Published: June 2009

ZnO powders were prepared via the solid‐state reaction at 800°C in air, nitrogen, and hydrogen atmospheres, respectively. Raman spectra show that the concentration of oxygen vacancies greatly increases when the sample is prepared in hydrogen atmosphere. The particle size distributions of the powders prepared in air and nitrogen atmospheres are better than that in hydrogen atmosphere. The dielectric parameters of the samples were determined in the frequency range of 8.2–12.4 GHz. Results show that the real part ɛ′ and imaginary part ɛ″ of complex permittivity of the sample prepared in hydrogen atmosphere reveal the greatest values in three samples. The loss mechanism of the samples was discussed.
Low Shrinkage Nanoscaled Transition‐Alumina Crystal Aggregates of Gibbsite
Authors: Yen Fu‐Su , Cheng Pei‐Ling , Huang Hong‐Yun , Lin Tien‐Chun
Published: June 2009

The low volume shrinkage phenomena occurring during thermal treatments of gibbsite (Al(OH)3) crystal were examined using TEM techniques. Normally, gibbsite shows a pseudomorphic transformation. The outward gibbsite crystal form can be preserved despite the fact that phase transformation proceeds from gibbsite to χ‐, to κ‐, then to α‐phase alumina. Examinations revealed that a sequential nanocrystal habit evolution developed, from χ‐flak to κ‐pillar or pole, then to α‐pea pods, as phase transformation proceeded. Calculations relating the increases in sequential density with the corresponding new packing patterns exhibited as transition phases occur demonstrate that pseudomorphic transformation can be performed perfectly. It is this mechanism that eventually leads to the low volume shrinkage of gibbsite aggregates.
A Novel Mechanism for Relaxor–Ferroelectric Transition in PLZT(8/65/35)
Authors: Somasekharan Divya Anickattu , Kumar Viswanathan
Published: June 2009

We report a novel mechanism for the spontaneous transition to the ferroelectric (FE) phase in a typical relaxor, PLZT(8/65/35). Dielectric, FE, induced strain, and structural studies reveal the influence of acceptor dopant Cu2+ on this transition. That this transition occurs under zero‐field conditions reveals yet another challenge in the use of copper metal electrodes for PLZT‐based thin‐film devices.
Influence of MoSi2 Addition on Load‐Dependent Fretting Wear Properties of TiB2 Against Cemented Carbide
Authors: Raju G. Brahma , Basu Bikramjit
Published: June 2009

In an earlier work, it was observed that the use of MoSi2 (up to 10 wt%) enhanced the densification and mechanical properties of TiB2. Therefore, the motivation of this study is three‐fold: (a) to assess whether a small amount of MoSi2 addition can enhance wear resistance property, (b) to study whether the MoSi2 addition will influence the formation of a tribochemical layer, and (c) to correlate the wear resistance with material properties in TiB2–MoSi2 materials. In order to address these issues, a series of fretting experiments were conducted systematically by varying load (2, 5, and 10 N) at an oscillating frequency of 4 Hz and a 100 μm linear stroke, for a duration of 100 000 cycles with a cemented carbide (WC—6 wt% Co cermet) ball as a counterbody. The average coefficient of friction of the TiB2 samples varied within a narrow range (0.50–0.54), without being much affected by either the sintering additive or the load. The wear volume increased with increasing load, while the specific wear rate of all the TiB2 compositions falls within a mild wear regime (1.1–3.4 × 10−6 mm3/Nm). Based on the experimental results, it can be said that the addition of MoSi2 degrades neither the wear resistance properties nor the frictional properties of TiB2, within the investigated load regime. The microcracking‐induced spalling has been found to be the dominant mechanism and, consequently, the wear volume is observed to have a linear dependency on the abrasion parameter. It is noteworthy that the tribo‐oxidation as well as the formation of finer wear debris particles occurs to a limited extent.
Hydrothermal Synthesis of Petal‐Like Alumina Flakes
Authors: Naskar Milan Kanti
Published: June 2009

Petal‐like alumina flakes were prepared by hydrothermal reaction at 170°C for 6 h with aqua‐based precursor materials. The gel particles were calcined at 550°–1200°C. The gel and calcined particles were characterized by differential thermal analysis (DTA), thermogravimetry (TG), X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), multipoint Brunauer–Emmett–Teller (BET) surface area, and field emission scanning electron microscopy (FESEM). Crystallization of alumina was confirmed by DTA and XRD studies. XRD results showed that boehmite particles were formed in as‐prepared sample while γ‐alumina (γ‐Al2O3) persisted up to 800°C followed by the appearance of θ‐alumina (θ‐Al2O3) at 1000°–1200°C. The characteristics Al–O vibrations in alumina polymorphs were examined by FTIR study. FESEM confirmed the formation of petal‐like alumina flakes with the assembly of alumina nanorods.
Nanostructural Evolution of Titania‐Based Materials Using Modified Titanium Precursors
Authors: Arrachart Guilhem , Cassidy David J. , Karatchevtseva Inna , Triani Gerry
Published: June 2009

Titanium ethoxide [Ti(OEt)4] was modified with aminobenzoic acid (AB) or aminosalicylic acid (AS) in order to control the hydrolysis and condensation rates, and to allow the preparation of organic–inorganic hybrid materials. A suite of complementary techniques, including Fourier transform infrared spectroscopy, NMR, SEM, thermogravimetric analysis, and X‐ray diffraction, were used to elucidate the effects of incorporating an organic functional group into the precursor chemistry and its subsequent affect on the structure and morphology of the resultant hybrid material. The annealing behavior of the resulting hybrid titanium base materials was also investigated. Our studies show that both amino acid organic ligands, AB and AS, chemically bounded to the titanium complex, effect the precursor reactivity, specifically the hydrolysis and polycondensation reactions, which control the evolution and formation of the nanohybrid‐based titania material. Following sol–gel processing, the nanohybrid materials are amorphous, due to the incorporation of the organic component. The phase transition (amorphous–anatase–rutile) observed during annealing from 25° to 800°C show subtle differences in the crystallization behavior, which are associated with the nature of the organic ligand.
Reactive Hot Pressing and Properties of Nb2AlC
Authors: Zhang Wei , Travitzky Nahum , Hu Chunfeng , Zhou Yanchun , Greil Peter
Published: June 2009

Dense Nb2AlC ceramic was synthesized from NbC, Nb, and Al powder mixture at 1650°C and a pressure of 30 MPa for 90 min using an in situ reaction/hot‐pressing method. The reaction kinetics, microstructure, physical, and mechanical properties of the fabricated material were investigated. A thermal expansion coefficient of ∼8.1 × 10−6 K−1 was measured in the temperature range of 30°–1050°C. At room temperature a thermal conductivity of ∼20 W·(m·K)−1 and a Vickers hardness of ∼4.5 GPa were determined. The material attained Young's modulus, four‐point bending strength and fracture toughness of ∼294 GPa, ∼443 MPa, and ∼5.9 MPa·m1/2, respectively. The nanolayered grains with a mean grain size of 17 μm contributed to the damage tolerance of this ceramic. Quenching from 600°, 800°, and 1000°C into water at room temperature resulted in decrease in bending strength from 443 MPa for the as‐synthesized Nb2AlC to 391, 156, and 149 MPa, respectively.
Lead Zirconate Titanate–Magnetoplumbite Composites: A First Step Toward Multiferroic Ceramics?
Authors: Silvestroni Laura , Kleebe Hans‐Joachim , Kungl Hans , Lauterbach Stefan , Müller Mathis , Hoffmann Michael J.
Published: June 2009

When lead zirconate titanate (PZT) is acceptor doped way above the solubility limit of Fe3+, crystalline secondary phases become thermodynamically stable that are antiferromagnetic and ferromagnetic, i.e., plumboferrite, PbFe4O7, and magnetoplumbite (MP), PbFe12O19, respectively. Three materials were studied by X‐ray diffractometry and transmission electron microscopy, with 3 mol% Fe (B‐site) and high volume fractions of iron, which corresponds to a 1.5 and 6 mol% of MP addition, with emphasis placed on the phase and microstructure evolution, depending on the dopant level. Although the addition of the high iron content resulted in the formation of the desired ferromagnetic phase MP, homogeneously dispersed within the PZT host matrix, the densification kinetics became quite sluggish, resulting in rather porous multiferroic ceramics.
Growth of yellow‐headed blackbird Xanthocephalus xanthocephalus nestlings in relation to maternal body condition, egg mass, and yolk carotenoids concentrations
Authors: Newbrey Jennifer L. , Reed Wendy L.
Published: June 2009

Condition‐dependent resource allocation to eggs can affect offspring growth and survival, with potentially different effects on male and female offspring, particularly in sexually dimorphic species. We investigated the influence of maternal body condition (i.e., mass‐tarsus residuals) and two measures of female resource allocation (i.e., egg mass, yolk carotenoid concentrations) on nestling mass and growth rates in the polygynous and highly size dimorphic yellow‐headed blackbird Xanthocephalus xanthocephalus. Egg characteristics and carotenoid concentrations were obtained from the third‐laid egg of each clutch and were correlated with the mass and growth rates of the first two asynchronously hatched nestlings. Maternal body condition was associated with the growth of first‐hatched, but not second‐hatched nestlings. Specifically, females in better body condition produced larger and faster growing first‐hatched nestlings than females in poorer body condition. As predicted for a polygynous, size‐dimorphic species, females that fledged first‐hatched sons were in better body condition than females that fledged first‐hatched daughters. Associations between egg mass, yolk carotenoid content, and nestling growth were also specific to hatching‐order. Egg mass was positively correlated with the mass and growth rates of second‐hatched nestlings, and yolk concentrations of β‐carotene were positively correlated with second‐hatched nestling mass. Surprisingly, the relationship between yolk lutein and hatchling growth differed between the sexes. Females with high concentrations of yolk lutein produced larger and faster growing first‐hatched sons, but smaller first‐hatched daughters than females with lower lutein concentrations. Mass and growth rates did not differ between first‐ and second‐hatched nestlings of the same sex, despite asynchronous hatching in the species. Results from this study suggest that maternal body condition and the allocation of resources to eggs have carotenoid‐, sex‐, and/or hatch‐order‐specific effects on yellow‐headed blackbird nestlings.
Magnetic resonance Imaging versus chemical fat extraction in a small passerine, the willow warbler Phylloscopus trochilus: a fat‐score based statistical comparison
Authors: Hedenström Anders , Fagerlund Timmy , Rosén Mikael , Wirestam Ronnie
Published: June 2009

The amount of fat of a bird is a fundamental metric commonly used by avian biologists in studies of migration, winter energy management and condition. The methods used for estimating fat content range from simply measuring body mass and subtracting the estimated lean mass, visual scoring of subcutaneous fat deposits, to destructive extraction using a Soxhlet apparatus. We used magnetic resonance imaging (MRI) for non‐invasive estimation of fat content in willow warblers Phylloscopus trochilus. According to an indirect comparison, made using a standardized fat scoring system as a common measure, the MRI method gave very similar fat amount as Soxhlet extraction and we discuss advantages of using MRI over alternative methods. It was also shown that the commonly used fat scoring system yielded a nonlinear relationship between fat mass and fat score.
Further evidence of genetic heterogeneity segregating with hereditary gingival fibromatosis
Authors: Ye Xiaoqian , Shi Lisong , Yin Wei , Meng Liuyan , Wang Qing Kenneth , Bian Zhuan
Published: June 2009

Aim: To clinically characterize and map the disease‐associated locus in a five‐generation Chinese family with autosomal dominant early‐onset hereditary gingival fibromatosis (HGF).

Material and Methods: A complete oral examination was conducted. Genomic DNA samples were obtained from 14 individuals. Short tandem repeats markers, which encompass four previously known loci related to HGF, were genotyped. Two‐point log of the odds (LOD) scores were calculated using MLINK program of the LINKAGE software, multipoint and non‐parametric linkage (NPL) analysis were performed using the GENEHUNTER software.

Results: Clinical evaluation and histological examination of this family suggested typical features of HGF. The onset age was early in the generations, ranging between 1 and 2 years. None of the tested markers showed cosegregation among affected individuals. Genotyping data from four putative regions yielded significant negative two‐point LOD scores (<−2.0) at θ=0. The maximum multipoint LOD scores and NPL analysis revealed exclusion of these loci as well.

Conclusions: Exclusion of linkage in this family to any of the known HGF loci proved the existence of a novel locus for autosomal dominant HGF and showed that this rare disorder is far more heterogeneous than previously expected.
Congenital myofibroma of the skin mimicking a piloleiomyoma
Authors: Inoue Takuya , Sada Asuka , Mori Toru , Misago Noriyuki , Narisawa Yutaka
Published: June 2009

Myofibroma is an uncommon benign soft tissue disorder, which is usually congenital or present in early infancy. Myofibroma usually manifests as a single mass. When there are multiple lesions, the term myofibromatosis is used. The characteristic histopathological feature of the myofibroma is the coexistence of two distinct areas. One area mainly contains plump spindle cells with thin blunt‐ended nuclei and eosinophilic cytoplasm, thus indicating myoid characteristics. The other area contains either round or polygonal cells with slightly pleomorphic, hyperchromatic nuclei or small spindle cells typically arranged around a distinct hemangiopericytoma‐like vascular pattern. In the present case, the majority of the tumor was composed of the plump myoid spindle cells. This led to an initial diagnosis of a piloleiomyoma. However, the tumor cells were not immunohistochemically positive for desmin. Moreover, careful examination revealed a hemangiopericytoma‐like vascular pattern characterized by the presence of high cellular areas with irregular vascular spaces. These features led to the final diagnosis of the myofibroma. It is therefore important to recognize the leiomyoma‐like variants of myofibromas.

Inoue T, Sada A, Mori T, Misago N, Narisawa Y. Congenital myofibroma of the skin mimicking a piloleiomyoma.
Effect of synthetic vernix biofilms on barrier recovery of damaged mouse skin
Authors: Oudshoorn Marion H. M. , Rissmann Robert , Van Der Coelen Dennis , Hennink Wim E. , Ponec Maria , Bouwstra Joke A.
Published: June 2009

Abstract:  The aim of this work was to investigate whether topical application of synthetic biofilms supports and accelerates the recovery of the murine skin barrier, disrupted by sequential tape stripping. Therefore, various biofilms were applied topically on disrupted mouse skin to determine which formulation could improve barrier function, as was observed previously for the natural biofilm vernix caseosa (VC). The biofilms [i.e. particles (synthetic corneocytes) embedded in a synthetic lipid matrix] mimic closely the physicochemical properties and structure of VC. Various formulations were prepared using different particle:lipid ratios, particles with different initial water content and uncoated or lipid‐coated particles. It was observed that application of all tested formulations improved the skin barrier recovery rate and reduced crust formation and epidermal hyperproliferation. However, only one of the biofilms [i.e. B1; composed of uncoated particles with 50% (w/w) initial water content and particle:lipid ratio of 2:1] mimicked the effects of native VC most closely. This indicates the importance of the presence of individual components, i.e. barrier lipids and water, as well as the ratio of these components. Consequently, these observations suggest the potential use of this biofilm treatment clinically.
Neuroendocrine activity of the melanocyte
Authors: Slominski Andrzej
Published: June 2009

Abstract:  More than 15 years ago, we have proposed that melanocytes are sensory and regulatory cells with computing capability, which transform external and/or internal signals/energy into organized regulatory network(s) for the maintenance of the cutaneous homeostasis. This concept is substantiated by accumulating evidence that melanocytes produce classical stress neurotransmitters, neuropeptides and hormones, express corresponding receptors and these processes are modified and/or regulated by ultraviolet radiation, biological factors or stress. Examples of the above are catecholamines, serotonin, N‐acetyl‐serotonin, melatonin, proopiomelanocortin‐derived adrenocorticotropic hormone, β‐endorphin or melanocyte‐stimulating hormone peptides, corticotropin releasing factor, related urocortins and corticosteroids including cortisol and corticosterone as well as their precursors. Furthermore, their production is not random, but hierarchical and follows the structures of classical neuroendocrine organizations such as hypothalamic‐pituitary‐adrenal axis, serotoninergic, melatoninergic and catecholaminergic systems. An example of an intrinsic but overlooked neuroendocrine activity is production and secretion of melanogenesis intermediates including l‐DOPA or its derivatives that could enter circulation and act on distant sites. Such capabilities have defined melanocytes as neuroendocrine cells that not only coordinate cutaneous but also can affect a global homeostasis.
p63 directly induces expression of Alox12, a regulator of epidermal barrier formation
Authors: Kim Soeun , Choi Irene F. , Quante Jessica R. , Zhang Lei , Roop Dennis R. , Koster Maranke I.
Published: June 2009

Abstract:  Epidermal development and differentiation are tightly controlled processes that culminate in the formation of the epidermal barrier. A critical regulator of different stages of epidermal development and differentiation is the transcription factor p63. More specifically, we previously demonstrated elsewhere that p63 is required for both the commitment to stratification and the commitment to terminal differentiation. We now demonstrate that ΔNp63α, the predominantly expressed p63 isoform in postnatal epidermis, also plays a role in the final stages of epidermal differentiation, namely the formation of the epidermal barrier. We found that ΔNp63α contributes to epidermal barrier formation by directly inducing expression of ALOX12, a lipoxygenase which contributes to epidermal barrier function. Our data demonstrate that ΔNp63α directly interacts with the promoter of Alox12 in the developing epidermis. Furthermore, we found that the induction of Alox12 expression by ΔNp63α depends on intact p63 binding sites in the Alox12 promoter. Finally, we found that ΔNp63α can induce Alox12 expression only in differentiating keratinocytes, consistent with the role of ALOX12 in epidermal barrier formation.
The effect of moesin overexpression on ageing of human dermal microvascular endothelial cells
Authors: Lee Ju Hee , Hong In Ae , Oh Sang Ho , Kwon Yeon Sook , Cho Soo Hyun , Lee Kwang Hoon
Published: June 2009

Abstract:  Senescence of microvascular endothelial cells is known to play an important role in the pathophysiology of vascular diseases related to ageing, but the accurate mechanism or related genes are not known. Moesin, a cytoskeletal protein and the most potent candidate as an ageing‐related protein, showed obvious changes in expression when compared before and after ageing. In this study, a lentivirus was used to overexpress moesin in endothelial cells. The expression of cell cycle mediators such as p16, cyclin D1 and cdk4, which can be the markers of ageing, was compared by RNA and was shown to be suppressed in moesin overexpressed endothelial cells. In conclusion, it can be said that the expression of moesin delays senescence of human dermal microvascular endothelial cells and this fundamental discovery can be used as a basis for understanding the mechanism of ageing and age‐related diseases.